CA1194116A - Method and apparatus for indicating an operating characteristic of an internal combustion engine - Google Patents
Method and apparatus for indicating an operating characteristic of an internal combustion engineInfo
- Publication number
- CA1194116A CA1194116A CA000437704A CA437704A CA1194116A CA 1194116 A CA1194116 A CA 1194116A CA 000437704 A CA000437704 A CA 000437704A CA 437704 A CA437704 A CA 437704A CA 1194116 A CA1194116 A CA 1194116A
- Authority
- CA
- Canada
- Prior art keywords
- exhaust gas
- engine
- electrode
- gas stream
- packets
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
- F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
- F02D41/1444—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases
- F02D41/1466—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being a soot concentration or content
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/22—Safety or indicating devices for abnormal conditions
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M15/00—Testing of engines
- G01M15/04—Testing internal-combustion engines
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume, or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
- G01N15/0656—Investigating concentration of particle suspensions using electric, e.g. electrostatic methods or magnetic methods
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/62—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating the ionisation of gases, e.g. aerosols; by investigating electric discharges, e.g. emission of cathode
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B3/00—Engines characterised by air compression and subsequent fuel addition
- F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/008—Controlling each cylinder individually
Abstract
Method and Apparatus for Indicating an Operating Characteristic of an Internal Combustion Engine Abstract A method and apparatus are provided for indi-cating an operating characteristic of a periodically combusting internal combustion engine, such as a diesel engine, having exhaust gas issuing from one or more combustion chambers in a periodic manner through a duct. The particulate in the exhaust gas stream are electrically charged and of the same polarity, and are grouped in packets associated with the periodic combustion in the respective chambers.
An electrically conductive, passive electrode, preferably annular in shape, is disposed such that most or all of the exhaust gas flows therethrough so as to electrostatically sense, principally by in-duced image charge, the passage of the respective packets of charged particles. The electrode is electrically isolated from the duct. Circuitry with the probe converts the sensed induced image charge to a signal containing a series of pulsating com-ponents corresponding in time with the respective particle packets and corresponding quantitatively with the charge-quantity of the respective particle packets. An indicating device responds to the pul-sating signal and provides an indication of an operating characteristic of the engine, The electrode is preferably of short axial ex-tent relative to the packet interval to enhance resolution. Structure and circuitry may be provided to minimize soot deposition and/or leakage currents across an insulator between the electrode and duct.
In one instance, the indicating device may respond to the root mean square of the pulsating signal to provide a quantitative indication of the level of particulate in the exhaust gas stream. In another instance, the successive pulsations of the signal waveform may be displayed to afford evaluation of the performance of the respective combustion chambers and/or injectors.
An electrically conductive, passive electrode, preferably annular in shape, is disposed such that most or all of the exhaust gas flows therethrough so as to electrostatically sense, principally by in-duced image charge, the passage of the respective packets of charged particles. The electrode is electrically isolated from the duct. Circuitry with the probe converts the sensed induced image charge to a signal containing a series of pulsating com-ponents corresponding in time with the respective particle packets and corresponding quantitatively with the charge-quantity of the respective particle packets. An indicating device responds to the pul-sating signal and provides an indication of an operating characteristic of the engine, The electrode is preferably of short axial ex-tent relative to the packet interval to enhance resolution. Structure and circuitry may be provided to minimize soot deposition and/or leakage currents across an insulator between the electrode and duct.
In one instance, the indicating device may respond to the root mean square of the pulsating signal to provide a quantitative indication of the level of particulate in the exhaust gas stream. In another instance, the successive pulsations of the signal waveform may be displayed to afford evaluation of the performance of the respective combustion chambers and/or injectors.
Description
~-~9~.6 ~ 1 --Description Method and Apparatus for Indicating an Operating Characteristic of an Internal Combustion Engine Technical Field This invention relates to the technique and apparatus for indicating an operating characteristic of an internal combustion engine and more specifi cally to the method and apparatus for sensing the particulate in the exhaust gas stream issuing in a periodic manner from an internal combustion engine and indicatiny an operating condition of the engine from the sensed particulate.
Background Art Interest in maintaining high levels of air qual-ity have focused attention on the importance of re-ducing emissions from internal combustion engines, and especially the diesel engines which power a variety of on- and off-road vehicles. The manufac~
turers of such engines and vehicles, as well as tnose interested in the ongoing and/or periodic moni~oring and testing of exhaust gas particulate levels see~ accurate, reliable and relatively economical means for accomplishing that end.
The present industry standards for particulate emission measurements are opacity meters, which em-ploy optical techniques and gas filter patch samples~
The opacity meter, which provides greater measure-ment flexibility and continuous measurement capabi-lity operates on optical principles which require the provision of a source of light and means for sensing the level of light transmitted through and/
or reflected by par~icles contained in the exhaust gas stream.
Background Art Interest in maintaining high levels of air qual-ity have focused attention on the importance of re-ducing emissions from internal combustion engines, and especially the diesel engines which power a variety of on- and off-road vehicles. The manufac~
turers of such engines and vehicles, as well as tnose interested in the ongoing and/or periodic moni~oring and testing of exhaust gas particulate levels see~ accurate, reliable and relatively economical means for accomplishing that end.
The present industry standards for particulate emission measurements are opacity meters, which em-ploy optical techniques and gas filter patch samples~
The opacity meter, which provides greater measure-ment flexibility and continuous measurement capabi-lity operates on optical principles which require the provision of a source of light and means for sensing the level of light transmitted through and/
or reflected by par~icles contained in the exhaust gas stream.
2 --Opacity meters, however, require a relatively stable mounting arrangement and frequent cleaning and are not particularly well suited for on-vehicle applications. Moreover, the relatively high cost of opacity meters minimizes their appeal in a large volume market. Lastly, because of the optical char-acteristics typical of these meters, particle emis-sions one micron in size and larger have a greater sensitivity to detection than particles below the one micron level. Accordingly, most optical detec-tors are referred to as smoke meters rather than paxticulate emissions detectors because of this size discrimination effect which does not present a repre-sentative plcture of the total exhaust gas particu-late emissions, Instruments have existed for measuring the con-centration of particles, i.e. aerosols, in a flowing gas stream utilizing electrostatic techniques. How-ever, these instruments typically establish a high voltage corona in the particle flowpath for placing a charge on the flowing particles~ Examples of such instruments are illustrated and disclosed in U.S.
Patent No. 3,526,828 issued September 1, 1970 to K.
T. Whitby i--or Method and Apparatus for Measuring Particle Concentration and in U.S~ Patent No.
Patent No. 3,526,828 issued September 1, 1970 to K.
T. Whitby i--or Method and Apparatus for Measuring Particle Concentration and in U.S~ Patent No.
3,114,877 issued December 17, 1963 to S. B. Dunham for Particle Detector Having Improved Unipolar Charg-ing Structure. In U.S. Patent No. 3,359,796 issued December 26, 1967 to R. C. Dimick for Apparatus for Measuring Mass Flow Using a Shielded Probe, an in-strument is disclosed which measures the mass flow of charged solid particles entrained in a flowing gas stream, which particle charges are ac~uired by frictional contact with the wall of the conduit.
Impact of the charged particles with a sensor element creates a small electrical current which is used as a measure of the particle mass flow. Operation of this device is limited to situations where fric-tional charging is the principal charging process and wher~ flow velocities are low enough for impact charge collection to overcome gas dynamics. Thus, no consideration is given to uslng that device for measuring the emission level of particulates in the exhaust from an internal combustion engine.
In U.S. Patent No, 3,470,551 issued September 30, 1969 to A. A. Jaffe et al for Fire and Smoke Detector, there is disclosed a device for detecting the existence of fire and smoke by sensing the net electrical charge associated with particles result-ing Xrom combustion. This device requires a field-free region for operation. Moreover, it is limited to two-state operation, i.e. "smoke" or "no-smoke"
and is not intended to measure differing particu-late levels of the exhaust gas stream issuing from an internal combustion engine.
A smoke measuring device for the exhaust gases from internal combustion engines is described in U.S. Patent 3,744,461 issued July 10, 1973 to J. Dv Davis for Method and Apparatus for Reducing Exhaust Smoke in Internal Combustion Engines. That smoke measuring device utilizes the principle that carbon particles in the exhaust gas stream issuing from an internal combustion engine are electrically charged.
An electrode is placed in the exhaust gas stream, the charges are collected at the electrode by im-paction, and electrical circuitry provides an output signal corresponding to the potential developed be-tween the electrode and the exhaust duct, which signal may, in highly selective cases such as low flow velocity, be indicative of a smoke density level and may be used to control the quantity of fuel delivered to the engine.
3 1~3 L~
The smoke measuring device of the aforemen-tioned Davis patent~ while providing some measure of the paxticulate level in an engine exhaust gas stream, also exhibits cer-tain limitations. By re-5 lying on charge collection by impaction, the elec~
trode must have a relatively large surface area in and~or adjacent to the gas stream and requires a significant electrical potential to overcome gas dynamic flow stream forces. Further, the impaction process can significantly ~horten the life of the electrode by erosion. Additionally, ~ecause of the large extent of the electrode in the direction of gas flow, the resulting signal is generally representative of an average of the discrete exhaust outputs of several cylinders.
Although several factors may contribute to ex-cessive smoke or particulate emissions from inter nal combustion engines, one factor may be the im-proper operation of a fuel injector in a particular cylinder. Moreover, such defective operation of the fuel injector may degrade the engine's per-formance and thereby adversely arfect fuel economy.
It is therefore, a principal object of the present invention to provide an improved apparatus for indicating an operating characteristic of a periodically combusting internal combustion engine by sensing the particulate emissions in the exhaust gas stream issuing from the engine and deriving the indication therefrom.
It is a further object of the invention to provide a particulate sensor whicn is relatively durable, long lived and is suited for con-tinuous on-vehicle application.
It is yet a further object of the invention to provide an improved apparatus for sensing and indicatîng quantitatively the level of particulate in an exhaust gas stream issuing in a periodic manner from an internal combustion engine.
It is a still further object of the present invention to provide a method and apparatus for sensing and indicating the relative performance of fuel injectors in a multi-injector/multi-cylinder engine based on the particular emission character-istics of the respective cylinders.
Disclosure of the Invention According to the present invention, there is provided a technique and apparatus for indicating an operating characteristic of a periodically com-busting internal combustion engine, which engine has one or more combustion chambers and an exhaust gas stream issuing in a periodic manner through ducting fxom the combustion chambers. The exhaust gas stream contains electrically charged particles of the same polarity at a monitoring location down-stream of the engine combustion chambers, and theengine's periodic discharge of exhaust gas from respective cylinders causes the charged particles to be grouped in packets. An electrically conduc-tive passive electrode, preferably of annular con-figuration, is disposed in proximity with the ex-haust gas stream at the monitoring location to electrostatically sense, principally by means of an induced image char~e, the passage of the re-spective packets of charged particles. The elec-trode is electrically isolated from the exhaustduct and is preferably configured and~or positioned to minimize any blockage of the flow of exhaust gas. Signal developing circuitry is connected -to the sensing electrode for providing an electrical signal in respons~ to the sensed passage o~ the particle packets. That signal contains a series of distinct pulsating components corresponding in time with the passage of the respective said particle packets and corresponding quantitatively with the charge-quantity of the respective parti-cle packets. ~n indicating devicereceives these pulsat-ing signals as its input and provides therefrom an indication of an operating characteristic of the engine.
In a preferred embodiment the sensing elec-trode is an electrically conductive closed annulus or loop positioned in proximate coaxial relation with the exhaust gas stream and which preferably has an axial extent which is short relative to spacial dimension of successive par-ticle packets.
The electrode may be incorporated in the exhaust gas duct or pipe, or it may be located a short distance beyond the downstream end thereof. The diameter of the annular electrode is sufficiently large to enable a substantial portion or all of the exhaust gas stream to pass therethrough and may typically approach or exceed the diameter of the exhaust gas duct. Because the sensing elec-trode either is in, or is in close proximity with, the exhaust gas stream, it may be desirable to provide a guard ring for the conduction of leakage currents and/or a shadow shield to minimize the ~L~9~
accumulation of soot on an insulating surface which supports the electrode.
Signal developing circuitry is connected to the electrode such thata pulsating signal is developed thereby in response to the passage of respective charged particle packets through or otherwise past the sensing electrode. The resultingpulsating signal corresponds in time with the passage of the re-spective charged particle packets and corresponds 1~ quantitatively with the charged particles in a re spective packet. Due to considerations of Gaussl Law, the annular probe configuration provides equal weighting of each particle passing through the an-nulus independent of radial charge density distri-bution.
A device responsive to at least the pulsatingcomponents of the developed signal provides there-from an indication of an operatiny characteristic of the engine. In one embodiment, the device may respond to the root mean square of the pulsating signal to provide a quantitative indication of the level of particulate in the e~haust gas stream.
In another embodiment the device may comprise a cathode ray tube or the like for displaying the successive pulsations of the signal waveform to afford evaluation of the performance of the re-spective individual cylinders and~or fuel injec-tors. In this latter regard, correlation of a par-ticular displayed signal with operation of a specific injector may be accomplished by perturb-ing the operation of the particular injector and ~9~
noting such change in the display of a particular signal in the se~uence of signals corresponding to successive injectors. Such corr~lation o~ a parti-cular displayed signal with a particular injector might also be calculated automatically as a Eunc-tion of system geometry and present operating con-ditions.
Brief Description of the Drawings Fig. 1 is a diagxamma-tic view of an internal com~ustion engine having the electrostatic induc-tion particulate sensor installed in the exhaust stream thereof and providing a pulsating signal to cir-cuitry for indicating an operating characteris-tic of the engine;
Fig. 2 is a view of a preferred form of the electrostatic induction particulate~sensing pro~e viewed in tne direction of exhaust gas flow;
Fig. 3 is a view of the probe of Fig. 2 per-pendicular to the gas flow, including a mounting arrangement and illustrating the signal developing and utilizing circuitry in greater detail;
Fig. 4 is another mounting arrangement for a probe in accordance wi-th the invention;
Fig. 5 is a further mounting arrangement for a probe in accordance with the invention;
Fig. 6 is a display of the sensed signal for relatively low-level particulate packets in the exhaust;
Fig. 7 is a display of the sensed signal for relatively higher level particulate packets in the exhaust; and Fig. 8 is a display of the sensed signal for differing particulate levels in successive parti-culate packets from respective successive combus~
tion chambers.
Best Mode for Carrying Out the Invention Referring to Fig,l there i5 depicted within one of the combustion chambers 10 of a multi-cylin-der internal combustion engine, such as compression ignition engine 12, the ionization which results from the combustion process. This phenomenon, in which the g~s in the immediate combustion region becomes electrically conducting, is the well known principle upon which flame ionization and combus-tion detectors are based. Xn the operation of in-ternal co~ustion engines, and especially compression ignition or diesel engines, various particu-lates 16 are produced as a result of incomplete combustion. These particulates may vary in size and composition, and encompass a wide distribution, including many less than one micron in size.
Since these particles 16 are produced within the individual cylinders of the engine, they provide sites upon which free charg~s resulting from the combustion process can attach. As is usual with attachment or clustering reactions taking place at atmospheric pressures or above, charge selec~
tion occurs, i.e. only positive or only nega-tive charge species ultima~ely reside on the finely divided particles 16.
For purposes of illustration in Fig. 1, the particles 16 are shown to have acquired a positive charge as they begin movement away from the combus-tion chamber through the exhaust. Subsequent S to the charge attachment process ~hich takes place in combustion chamber 10, charge separation results as a consequence of the particles 16 being dominated by gas path flow forces, whereas the unattached charges, i.e. negative charges in Fig. 1, which have significantly greater mobilities because of their much smaller masses, are dominated by elec-trostatic forces. Accordingly, a rapid loss of these lighter (negative) particles to the walls of the cylinder and associated manifold results.
The degree to which this charge separation occurs is a function of the concentration of the particles 16 produced in each individual cylinder as a re-sult of the incomplete combustion taking place.
Specifically, the greater the formation of parti-cles, the greater will be the attachment of onecharge thereto and the separation therefrom of the other charge. Accordingly, determination of the quantity of charge provides a direct measure of the level of particulate in the engine exhaust gas stream.
It has been demonstrated that once charge-separated, these charged particles, designated 16' in Fig. 1, passed directly through the engine exhaust system to the outside atmosphere. Impor-tant -to the present invention in which the engine 12 is of the type which periodically combusts its fuel in one or more combus-tion chambers and then discharges its exhau,t in periodic pulses, as by valving 11 or the like, it has also been found that the packet of charged particles resulting from the exhaust discharge of an individual cylinder passes relatively unimpeded through even the exhaust staging of a turbocharger. This occurs primarily because flow forces dominate over electrostatic forces under typical engine operating conditions Moreover, the packet of particles from each parti-cular cylinder remains relatively intact and sepa-rate from those of each of the other cylinders, as in the form of discrete pulses~ These packets of charged particles are represented by dense groups of charged particles 16' in Fig~ 1.
The detection of the charged particles 16' in the exhaust duct, or pipe, 20 of engine 12 is ac-complished by use of an electrically passive elec-trostatic induction probe or electrode 30 mounted downstream of the combustion ch~mbers 10 in opera-tive proximity with the exhaust gas stream. The term "electrically passive" as used herein means the probe does not operate on an impaction or charge collection principle, and thus requires little or no biasing potential for signal genera-tion, although some bias may be used in conjunction with a guard ring as described hereinafter. The probe 30 might be mounted in an extension conduit associated with a test stand for connection with the exhaust pipe 20 of engine 12 to test or diagnose the engine. In another application, the probe 30 may be mounted directly in the ex'naust system of an engine for on~vehicle use. ~n insulator 32 pro-vides electrical isolation from pipe 20.
The key to providing a truly representative measure of the passage of particles 16' in the exhaust resides in the fact that relatively little or none of the actual charge on the particles ls collected by the probe. ~ather r the passage of substantially all of the charged particles is detected because an image charge of opposite sign is induced in the conducting probe electrode 30 as a charged particle approaches the vicinity of the probe surface. This results in a real elec-trical current flow through signal developing cir-lQ cuitry 33 connected to probe electrode 30, as willbe hereinafter described. By virtue of the induced image charge phenomenon, as the charged particle recedes in the flow away from electrode 30, the magnitude of the induced charge on that electrode surface decreases, resulting in a current flow in the opposite direction. Accordingly, although a small alternating current flow would be derived from the passage of a single charged particle 16', in the normal instance a much larger~magnitude signal results from the passage of a packet, or puff, of particles from the exhaust gas discharge of an individual cylinder.
For the purpose of comparing the performance of individual cylinders within a given engine, a time-resolved measurement or analysis of the signal, and specifically the AC-like pulsating signal in-duced in probe 30 by the passage of the exhaust gas puffs from the individual cylinders of the engine, provides this information directly. The charge induced in electrode 30, and thus current in the signal circuitry, is a function of the 1~9'~
- 13 ~
number or quantity of charged particles 16 passing the electrode in the exhaust gas stream at the par-ticular moment. An increase in particle concentra-tion during respective exhaust gas puffs is mani-S fested by an increase in the magnitude of the charge induced in electrode 30 and thus an increase in the voltage or current signal developed there-from.
Referring to Figs. 2 and 3, a preferred em-bodiment of electrostatic particle-detecting probe 30 is illustrated in greater detail. robe 30 com-prises an annular electrode formed of electrically conducting wire and oriented such that its axis is parallel to, and preferably substantially coaxial with, tne axis or centerline of the exhaust gas flow in the tubular pipe 2Q. It will be understood that ~he conductive probe 30 may have an insulating covering without impeding its performance in the present invention. In Fig. 3, the electrode 30 is shown mounted in and supported by ceramic insulator structure 32 which is in turn suitably mounted and sealed in an annular collar 60 which sealingly con-nects adjacent ends of pipe 20 at a break formed therein at a monitoring location.
In accordance with the invention, the length, Q, of the electrode 30 axially of the gas flow is limited in order to obtain good signal resolution between successive packets of charged particles.
It will be appreciated that as the number of com-bustion events per unit of time increases, the interval or length between successive particle packets decreases. Therefore, the leng~h, Q, of electrode 30 should be sufficiently short that at any instant it is sensing or responding to the charged particles of substantially only one packet, or preferably only an incremental portion thereof.
The interval or spacing between charged particle maxima in successive packets will, for a represen-tative system, largely be a function of the number of engine cylinders, the engine's operating dis-placement, the speed of the engine and the geometryof the exhaust ducting system. Typically, in a four cylinder diesel engine system capable of operating to 5,000 rpm, an electrode length, ~, of about 3-4 mm has given good results. For such lS a system, the length, Q, of the electrode 30 should generally be less than about 10 15 mm, which is much less than the typical diameter D of exhaust duct 20 thereat, i.e. 50 mm.
The electrode 30 is preferably affected ~y substantially all of the charged particles in a packet, rather than by a relative few nearest the electxode. Thus, because of considerations of Gauss' Law, an annular probe configuration is pre ferred, and a preferred electrode diameter, d, is one which is sufficiently large to allow substan-tially all of the exhaust gas stream in duct 20 to pass therethrough. The electrode diameter, d, preferably is near or exceeds the duct diameter.
In the Fig. 3 embodiment, the diameter, d, of elec-trode 30 somewhat exceeds duct diameter, D, so thatthe entire gas stream flows therethrough and no ~ 15 ~
flow blockage occurs. Typically, the radial thick-ness of an electrode 30 is only a}~out 1-4 mm to min-imize its surface area transverse ~o the flowing gas so as to minimize any flow blockage, particularly 5 if it is positioned in the gas stream.
E~eferring briefly to Figs. 4 and 5, there are illustrated alternative mounting arrangements for the electrostatic probe~ In Fig 4 the electrode 30' is also of annular form and insulated from pipe 10 20 by an insulator 32' which is sealingly installed directly in an opening in the wall of pipe 20. It will be noted that the diameter, d, of probe 30' is near, but slightly less than, the diameter, D, of pipe 20 so as to be in spaced (and thus insu-15 lated) relation with the pipe. It will be notedthat substantially all of the exhaust gas stream and entrained particulates pass through this probe and provide a signal having the requisite proper-ties, although ~his configuration does possess the 20 limitations of increased restriction of the flow path and exposure to soot deposition.
The electrode 30 " of Fig. 5 may also be annu-lar, and is mounted in an insulator 32'' which is supported by a bracket 70 mounted near the end of 25 exhaust pipe 20. The electrode 30" may be located axially at or just beyond the end of pipe 20 such that the insulator 32'' need not be mounted with a gas-tight seal. Moreover, the insulator 32 "
may be positioned upstream of the end of pipe 20, 30 to minimize or eliminate soot accumulation thereon.
In yet another possible embodiment (not shown~, the probe electrode might ~e embedded in an annular insulator, which insulator might be inserted into the exhaust duct or form an extension thereto However, in such instance care must be taken to avoid build-up of soot or other conductive deposits on the insulator.
A high degree of electrical isolation between probe 30 and the conductive portions of the duct 20 must be maintained. If the insulator 32 is posi-tioned such that it is exposed to the exhaust gasstream, the potential for soot accumulation on it exists, which may in turn give rise to leakage currents, particularly when damp. To minimize soot accumulation, one, or possibly two shadow shields 80a and 80b in Fig. 3 or 80'a and 80'b in Fig. 4, may be arranged to shadow the surface of the insulator from the direct gas flow.
Whether or not shadow shields are employed, leakage currents involving the probe electrode may be minimized through use of a guard ring. Accord-ingly, the insulator 32 in Fig. 3 and the insulator 32' in Fig. 4 include guard rings 36, 36' respec-tively. Insulator 32 is comprised of an inner cylindrical insulator 32a and a radially outer cylindrical insulator 32b concentric with insulator 32a. The base of annular electrode 30 is fixedly mounted, as by a friction fit or bonding, into inner insulator 32a. The insulator 32 also includes a conductive metal guard ring 36 intermediate and af-fixed to the inner ana outer insulators 32a, 32brespectively. Guard ring 36 is cylindrical and is concentric with insulators 32a, 32b and the por~
tion of probe 30 extending therethrough. The guard ring 36 is operated at substantially the same po-ten;
tial as the probe electrode 30, -thus forming a re-gion within and across the surface of the ceramicwhich is at substantially the same potential as the electrode 3Q. Accordingly, no leakage current can flow across this region. Leakage curren-ts from the surrounding structure of engine 12 and exhaust duct 20 can pass over the outer insulator 32b, via the soot, to the guard ring 36. From the guard ring 36, these leakage currents are shunted to ground and therefore do not arrive at the probe electrode 30.
Further, since the electrode 30 and the guard ring 36 are maintained at subs-tantially the same poten-tial~ no leakage of currents occurs ~etween the guard and the electrode.
Signal developing circuitry 33 is connected in the circuit of probe 30 between the probe and the ground reference potential. Signal developing cir-cuitry 33 includes a current-to-voltage converter 48 and a gain circuit 50. ~ssuming a 1 megohm re-sistor 51 across converter 48, a 1 microampere in-put provides a 1 volt output. Gain circuit 50 may typically have a gain factor of fifty.
In the embodiment illustrated in Fig. 3, the indicator 53 consists of a root mean square (rms) volt meter 54 which is connected to the output of signal developing circuitry 33 to receive the signal voltage as its input.
The output of the rm~ meter 54 may be a visual indication of the root mean square value of the signal occasioned by the passage of successive charged particle packets through the exhaust duct 20. This indication may be calibrated and ex-pressed in terms of the percentage of particulate in the exhaust gas stream or it may be referenced to opacity measurements and expressed as a change in opaci~y in the gas stream~ Alternatively or additionally, with the appropriate time constants applied to the signal~averaging circuitry a sub-stantially DC electrical signal indicative of the average value of particulate in th~ exhaust gas stream may be provided. Those time constants may be provided as function of engine combustion fre-quency. Such an indicating signal may additionally or alternatively he used for various control pur-poses.
The indicating device 53 might alternatively comprise a cathode ray tube (CRT) or similar dis-play device for displaying the output signal from circuitry 33 in a time-resolved rnanner. ~lore specifically, the signal provided by circuitry 33 may comprise the vertical, or Y, input to an X-Y
display in which time is measured along the X axis.
In other words, the pulsations appearing across resistor 5Q as a result of the passage of succes-sive particulate packets in the exhaust gas stream are displayed in a similar time-resolved succession on the face of a display device, as in Figs. 6, 7 and 8.
The signal displays of Figs. 6, 7 and 8 were obtained at a common engine speed and were provided hy connecting the output from the probe 3Q directly to the one megohm impedance at the "~" input of a Tektronics 7~34 oscilloscope. These displays are depicted as the upper trace in each of the Figs~ 6, 7 and 8. A lower trace is also contained in each of those Figs. for illustrating timing signals de-veloped, as for instance, from, and coinciding with, each second top dead center ~TD~ event associated with a particular one of t~le engine cylinders. The TDC signal may be provided in a known manner, as by a magnetic sensor (not shown) detecting a timing mark on the engine flywheel and suppressing the un~
wanted indication of each second TDC event. Al-though those timing signals are shown in time coin-cidence with the peak in the particula-te signals, it will be understood that such is normally not the case because of the delay interval between combus-tion chambers and the position in the exhaust gas stream at which probe 30 is stationed, i.e. phase lag. The upper and lower traces are preferably triggered by scme periodically recurring event in the engine operating cycle, as by the TDC signal constituting the illustrated timing signals men-tioned above, such that the trace pulsations appear relatively stationary. The peaks of the particulate signal on the upper trace have a magnitude of ap-proximately 20~ millivolts and typically represent a current level o several tenths o a micxoampere.
The particulate signals in Fig. 6 resulted for ex-haust gas conditions coinciding with measured opacity levels below about 1%.
Fig. 7 is an illustration similar to Fig. 6 with the only difference being that the particulate-level signals are of substantially greater magnitude ~i9~
- 2a -than those of Fig. 6 and are correspondingly repre-senta~ive of a higher particulate level, i.e. coin-ciding with measured opacity levels of about 13%.
Indeed, the magnitudes of the particulate level signals and measurements from an exhaustdilution tun-nel exhibit good correlation across a broad range of particulate levels~
Fig. 8 deplcts a display of a type similar to that of Figs. 6 and 7, however, it illustrates a difference in the relative particulate levels in the exhaust gas puffs issuing from different com bustion chambers. Specifically, the magnitudes of the particulate level signals or pulses A, C and D from the first, third and fourth cylinders ~not all shown~ in a four cylinder firing sequence are of relatively normal magnitude, whereas the magnitude of the signal B associated with the second cylinder in the sequence is of substantially greater magni-tude. By correlating the successive particulate signals with the respective engine cylinders from which they derive, it is possible to identify the cylinder and combustion chamber in which an abnor-mal particulate level condition arises. Such con-ditions axe generally caused by need for adjustment or repair of a particular one of the fuel injectors 14 and the identification of the offending injector is facilitated by this capability.
Correlation of a particulate packet signal with a particular cylinder and/or injector may be accomplished by "perturbing" the injector such that the "perturbance" appears in the partic~late signal, - 21 ~
then noting i-ts location in the sequence of parti-culate signal pulses and referencing the other pulses of predetermined firing or combustion se-quence thereto. An injector's operation may be "perturbed" by breaking the fuel line to it or by rotating its holder. Such technique is particularly suitable for identifying which of a plurality of injectors may be operating in an abnormal manner and is conveniently performed by repair and service personnel as well as by manufacturing personnel during the original checkout of the engine. It will be understood that in addition to identifying which cylinder and/or injector is malperforming, some indication as to the nature of that malper-formance may also be gained. For ins-tance, the magnitude of the particulate signal may be indi-cative of an e~cess or a shortage of fuel supplied by a particular injector.
It will be understood that the need to perturb an injector to identify its location in a sequence of displayed particulate pulses may he avoided if it is otherwise possible to determine the transport time between any displayed particulate pulse and the combustion chamber from which it issued. Fac-tors such as exhaust system geometry, engine speedengine operating event (i.e. TDC~, engine and/or air temperature, air pressure, etc. would typically be included in such a determination.
As an alternative or supplement to the rms meter 54, the signal provided by probe 30 might be sampled at a relatively high frequency and the samples then averaged to provide a measure of the particulate level.
The probe of the invention is preferably a loop, although other probes may be used. The probe need not be short-circuited on itself (as in ~igure 2).
The probe preferably has little or no electrical contact with the gas stream as described hereinbefore, and thus may take the forms described herein. Alter-natively, it may be totally electrically insulated from the gas stream by virtue of electrical lnsulation or size.
Although this invention has been shown and described with respect to detailed embodiments there-of, it will be understood by those skilled in the art that various changes in form and detail thereof may be made without departing from the spirit and scope of the claimed invention~ For instance, if the insulator which isolates the probe from the ex-haust pipe is sufficiently removed from contact with the exhaust gas, there may be no need for shadow shields and/or guard rings. Moreover, although the fully annular electrode configuration provides cer-tain ad~antages, it will be understood that the probe might be formed of one or more arcuate elec-trodes each extending but a portion of a full circle and electricall~ connected to one another. Moreover, the electrode might be linear and extend into or near the gas stream transverse to its direction of flow. As previously stated, such electrodes will X ,, ~9~
have a relatively small dimension, Q, in the direc-tion of gas flow, but are ~omewhat moxe dependent upon the radial location of charged particles in the exhaust gas stream that were the aforedescribed annular probes.
Impact of the charged particles with a sensor element creates a small electrical current which is used as a measure of the particle mass flow. Operation of this device is limited to situations where fric-tional charging is the principal charging process and wher~ flow velocities are low enough for impact charge collection to overcome gas dynamics. Thus, no consideration is given to uslng that device for measuring the emission level of particulates in the exhaust from an internal combustion engine.
In U.S. Patent No, 3,470,551 issued September 30, 1969 to A. A. Jaffe et al for Fire and Smoke Detector, there is disclosed a device for detecting the existence of fire and smoke by sensing the net electrical charge associated with particles result-ing Xrom combustion. This device requires a field-free region for operation. Moreover, it is limited to two-state operation, i.e. "smoke" or "no-smoke"
and is not intended to measure differing particu-late levels of the exhaust gas stream issuing from an internal combustion engine.
A smoke measuring device for the exhaust gases from internal combustion engines is described in U.S. Patent 3,744,461 issued July 10, 1973 to J. Dv Davis for Method and Apparatus for Reducing Exhaust Smoke in Internal Combustion Engines. That smoke measuring device utilizes the principle that carbon particles in the exhaust gas stream issuing from an internal combustion engine are electrically charged.
An electrode is placed in the exhaust gas stream, the charges are collected at the electrode by im-paction, and electrical circuitry provides an output signal corresponding to the potential developed be-tween the electrode and the exhaust duct, which signal may, in highly selective cases such as low flow velocity, be indicative of a smoke density level and may be used to control the quantity of fuel delivered to the engine.
3 1~3 L~
The smoke measuring device of the aforemen-tioned Davis patent~ while providing some measure of the paxticulate level in an engine exhaust gas stream, also exhibits cer-tain limitations. By re-5 lying on charge collection by impaction, the elec~
trode must have a relatively large surface area in and~or adjacent to the gas stream and requires a significant electrical potential to overcome gas dynamic flow stream forces. Further, the impaction process can significantly ~horten the life of the electrode by erosion. Additionally, ~ecause of the large extent of the electrode in the direction of gas flow, the resulting signal is generally representative of an average of the discrete exhaust outputs of several cylinders.
Although several factors may contribute to ex-cessive smoke or particulate emissions from inter nal combustion engines, one factor may be the im-proper operation of a fuel injector in a particular cylinder. Moreover, such defective operation of the fuel injector may degrade the engine's per-formance and thereby adversely arfect fuel economy.
It is therefore, a principal object of the present invention to provide an improved apparatus for indicating an operating characteristic of a periodically combusting internal combustion engine by sensing the particulate emissions in the exhaust gas stream issuing from the engine and deriving the indication therefrom.
It is a further object of the invention to provide a particulate sensor whicn is relatively durable, long lived and is suited for con-tinuous on-vehicle application.
It is yet a further object of the invention to provide an improved apparatus for sensing and indicatîng quantitatively the level of particulate in an exhaust gas stream issuing in a periodic manner from an internal combustion engine.
It is a still further object of the present invention to provide a method and apparatus for sensing and indicating the relative performance of fuel injectors in a multi-injector/multi-cylinder engine based on the particular emission character-istics of the respective cylinders.
Disclosure of the Invention According to the present invention, there is provided a technique and apparatus for indicating an operating characteristic of a periodically com-busting internal combustion engine, which engine has one or more combustion chambers and an exhaust gas stream issuing in a periodic manner through ducting fxom the combustion chambers. The exhaust gas stream contains electrically charged particles of the same polarity at a monitoring location down-stream of the engine combustion chambers, and theengine's periodic discharge of exhaust gas from respective cylinders causes the charged particles to be grouped in packets. An electrically conduc-tive passive electrode, preferably of annular con-figuration, is disposed in proximity with the ex-haust gas stream at the monitoring location to electrostatically sense, principally by means of an induced image char~e, the passage of the re-spective packets of charged particles. The elec-trode is electrically isolated from the exhaustduct and is preferably configured and~or positioned to minimize any blockage of the flow of exhaust gas. Signal developing circuitry is connected -to the sensing electrode for providing an electrical signal in respons~ to the sensed passage o~ the particle packets. That signal contains a series of distinct pulsating components corresponding in time with the passage of the respective said particle packets and corresponding quantitatively with the charge-quantity of the respective parti-cle packets. ~n indicating devicereceives these pulsat-ing signals as its input and provides therefrom an indication of an operating characteristic of the engine.
In a preferred embodiment the sensing elec-trode is an electrically conductive closed annulus or loop positioned in proximate coaxial relation with the exhaust gas stream and which preferably has an axial extent which is short relative to spacial dimension of successive par-ticle packets.
The electrode may be incorporated in the exhaust gas duct or pipe, or it may be located a short distance beyond the downstream end thereof. The diameter of the annular electrode is sufficiently large to enable a substantial portion or all of the exhaust gas stream to pass therethrough and may typically approach or exceed the diameter of the exhaust gas duct. Because the sensing elec-trode either is in, or is in close proximity with, the exhaust gas stream, it may be desirable to provide a guard ring for the conduction of leakage currents and/or a shadow shield to minimize the ~L~9~
accumulation of soot on an insulating surface which supports the electrode.
Signal developing circuitry is connected to the electrode such thata pulsating signal is developed thereby in response to the passage of respective charged particle packets through or otherwise past the sensing electrode. The resultingpulsating signal corresponds in time with the passage of the re-spective charged particle packets and corresponds 1~ quantitatively with the charged particles in a re spective packet. Due to considerations of Gaussl Law, the annular probe configuration provides equal weighting of each particle passing through the an-nulus independent of radial charge density distri-bution.
A device responsive to at least the pulsatingcomponents of the developed signal provides there-from an indication of an operatiny characteristic of the engine. In one embodiment, the device may respond to the root mean square of the pulsating signal to provide a quantitative indication of the level of particulate in the e~haust gas stream.
In another embodiment the device may comprise a cathode ray tube or the like for displaying the successive pulsations of the signal waveform to afford evaluation of the performance of the re-spective individual cylinders and~or fuel injec-tors. In this latter regard, correlation of a par-ticular displayed signal with operation of a specific injector may be accomplished by perturb-ing the operation of the particular injector and ~9~
noting such change in the display of a particular signal in the se~uence of signals corresponding to successive injectors. Such corr~lation o~ a parti-cular displayed signal with a particular injector might also be calculated automatically as a Eunc-tion of system geometry and present operating con-ditions.
Brief Description of the Drawings Fig. 1 is a diagxamma-tic view of an internal com~ustion engine having the electrostatic induc-tion particulate sensor installed in the exhaust stream thereof and providing a pulsating signal to cir-cuitry for indicating an operating characteris-tic of the engine;
Fig. 2 is a view of a preferred form of the electrostatic induction particulate~sensing pro~e viewed in tne direction of exhaust gas flow;
Fig. 3 is a view of the probe of Fig. 2 per-pendicular to the gas flow, including a mounting arrangement and illustrating the signal developing and utilizing circuitry in greater detail;
Fig. 4 is another mounting arrangement for a probe in accordance wi-th the invention;
Fig. 5 is a further mounting arrangement for a probe in accordance with the invention;
Fig. 6 is a display of the sensed signal for relatively low-level particulate packets in the exhaust;
Fig. 7 is a display of the sensed signal for relatively higher level particulate packets in the exhaust; and Fig. 8 is a display of the sensed signal for differing particulate levels in successive parti-culate packets from respective successive combus~
tion chambers.
Best Mode for Carrying Out the Invention Referring to Fig,l there i5 depicted within one of the combustion chambers 10 of a multi-cylin-der internal combustion engine, such as compression ignition engine 12, the ionization which results from the combustion process. This phenomenon, in which the g~s in the immediate combustion region becomes electrically conducting, is the well known principle upon which flame ionization and combus-tion detectors are based. Xn the operation of in-ternal co~ustion engines, and especially compression ignition or diesel engines, various particu-lates 16 are produced as a result of incomplete combustion. These particulates may vary in size and composition, and encompass a wide distribution, including many less than one micron in size.
Since these particles 16 are produced within the individual cylinders of the engine, they provide sites upon which free charg~s resulting from the combustion process can attach. As is usual with attachment or clustering reactions taking place at atmospheric pressures or above, charge selec~
tion occurs, i.e. only positive or only nega-tive charge species ultima~ely reside on the finely divided particles 16.
For purposes of illustration in Fig. 1, the particles 16 are shown to have acquired a positive charge as they begin movement away from the combus-tion chamber through the exhaust. Subsequent S to the charge attachment process ~hich takes place in combustion chamber 10, charge separation results as a consequence of the particles 16 being dominated by gas path flow forces, whereas the unattached charges, i.e. negative charges in Fig. 1, which have significantly greater mobilities because of their much smaller masses, are dominated by elec-trostatic forces. Accordingly, a rapid loss of these lighter (negative) particles to the walls of the cylinder and associated manifold results.
The degree to which this charge separation occurs is a function of the concentration of the particles 16 produced in each individual cylinder as a re-sult of the incomplete combustion taking place.
Specifically, the greater the formation of parti-cles, the greater will be the attachment of onecharge thereto and the separation therefrom of the other charge. Accordingly, determination of the quantity of charge provides a direct measure of the level of particulate in the engine exhaust gas stream.
It has been demonstrated that once charge-separated, these charged particles, designated 16' in Fig. 1, passed directly through the engine exhaust system to the outside atmosphere. Impor-tant -to the present invention in which the engine 12 is of the type which periodically combusts its fuel in one or more combus-tion chambers and then discharges its exhau,t in periodic pulses, as by valving 11 or the like, it has also been found that the packet of charged particles resulting from the exhaust discharge of an individual cylinder passes relatively unimpeded through even the exhaust staging of a turbocharger. This occurs primarily because flow forces dominate over electrostatic forces under typical engine operating conditions Moreover, the packet of particles from each parti-cular cylinder remains relatively intact and sepa-rate from those of each of the other cylinders, as in the form of discrete pulses~ These packets of charged particles are represented by dense groups of charged particles 16' in Fig~ 1.
The detection of the charged particles 16' in the exhaust duct, or pipe, 20 of engine 12 is ac-complished by use of an electrically passive elec-trostatic induction probe or electrode 30 mounted downstream of the combustion ch~mbers 10 in opera-tive proximity with the exhaust gas stream. The term "electrically passive" as used herein means the probe does not operate on an impaction or charge collection principle, and thus requires little or no biasing potential for signal genera-tion, although some bias may be used in conjunction with a guard ring as described hereinafter. The probe 30 might be mounted in an extension conduit associated with a test stand for connection with the exhaust pipe 20 of engine 12 to test or diagnose the engine. In another application, the probe 30 may be mounted directly in the ex'naust system of an engine for on~vehicle use. ~n insulator 32 pro-vides electrical isolation from pipe 20.
The key to providing a truly representative measure of the passage of particles 16' in the exhaust resides in the fact that relatively little or none of the actual charge on the particles ls collected by the probe. ~ather r the passage of substantially all of the charged particles is detected because an image charge of opposite sign is induced in the conducting probe electrode 30 as a charged particle approaches the vicinity of the probe surface. This results in a real elec-trical current flow through signal developing cir-lQ cuitry 33 connected to probe electrode 30, as willbe hereinafter described. By virtue of the induced image charge phenomenon, as the charged particle recedes in the flow away from electrode 30, the magnitude of the induced charge on that electrode surface decreases, resulting in a current flow in the opposite direction. Accordingly, although a small alternating current flow would be derived from the passage of a single charged particle 16', in the normal instance a much larger~magnitude signal results from the passage of a packet, or puff, of particles from the exhaust gas discharge of an individual cylinder.
For the purpose of comparing the performance of individual cylinders within a given engine, a time-resolved measurement or analysis of the signal, and specifically the AC-like pulsating signal in-duced in probe 30 by the passage of the exhaust gas puffs from the individual cylinders of the engine, provides this information directly. The charge induced in electrode 30, and thus current in the signal circuitry, is a function of the 1~9'~
- 13 ~
number or quantity of charged particles 16 passing the electrode in the exhaust gas stream at the par-ticular moment. An increase in particle concentra-tion during respective exhaust gas puffs is mani-S fested by an increase in the magnitude of the charge induced in electrode 30 and thus an increase in the voltage or current signal developed there-from.
Referring to Figs. 2 and 3, a preferred em-bodiment of electrostatic particle-detecting probe 30 is illustrated in greater detail. robe 30 com-prises an annular electrode formed of electrically conducting wire and oriented such that its axis is parallel to, and preferably substantially coaxial with, tne axis or centerline of the exhaust gas flow in the tubular pipe 2Q. It will be understood that ~he conductive probe 30 may have an insulating covering without impeding its performance in the present invention. In Fig. 3, the electrode 30 is shown mounted in and supported by ceramic insulator structure 32 which is in turn suitably mounted and sealed in an annular collar 60 which sealingly con-nects adjacent ends of pipe 20 at a break formed therein at a monitoring location.
In accordance with the invention, the length, Q, of the electrode 30 axially of the gas flow is limited in order to obtain good signal resolution between successive packets of charged particles.
It will be appreciated that as the number of com-bustion events per unit of time increases, the interval or length between successive particle packets decreases. Therefore, the leng~h, Q, of electrode 30 should be sufficiently short that at any instant it is sensing or responding to the charged particles of substantially only one packet, or preferably only an incremental portion thereof.
The interval or spacing between charged particle maxima in successive packets will, for a represen-tative system, largely be a function of the number of engine cylinders, the engine's operating dis-placement, the speed of the engine and the geometryof the exhaust ducting system. Typically, in a four cylinder diesel engine system capable of operating to 5,000 rpm, an electrode length, ~, of about 3-4 mm has given good results. For such lS a system, the length, Q, of the electrode 30 should generally be less than about 10 15 mm, which is much less than the typical diameter D of exhaust duct 20 thereat, i.e. 50 mm.
The electrode 30 is preferably affected ~y substantially all of the charged particles in a packet, rather than by a relative few nearest the electxode. Thus, because of considerations of Gauss' Law, an annular probe configuration is pre ferred, and a preferred electrode diameter, d, is one which is sufficiently large to allow substan-tially all of the exhaust gas stream in duct 20 to pass therethrough. The electrode diameter, d, preferably is near or exceeds the duct diameter.
In the Fig. 3 embodiment, the diameter, d, of elec-trode 30 somewhat exceeds duct diameter, D, so thatthe entire gas stream flows therethrough and no ~ 15 ~
flow blockage occurs. Typically, the radial thick-ness of an electrode 30 is only a}~out 1-4 mm to min-imize its surface area transverse ~o the flowing gas so as to minimize any flow blockage, particularly 5 if it is positioned in the gas stream.
E~eferring briefly to Figs. 4 and 5, there are illustrated alternative mounting arrangements for the electrostatic probe~ In Fig 4 the electrode 30' is also of annular form and insulated from pipe 10 20 by an insulator 32' which is sealingly installed directly in an opening in the wall of pipe 20. It will be noted that the diameter, d, of probe 30' is near, but slightly less than, the diameter, D, of pipe 20 so as to be in spaced (and thus insu-15 lated) relation with the pipe. It will be notedthat substantially all of the exhaust gas stream and entrained particulates pass through this probe and provide a signal having the requisite proper-ties, although ~his configuration does possess the 20 limitations of increased restriction of the flow path and exposure to soot deposition.
The electrode 30 " of Fig. 5 may also be annu-lar, and is mounted in an insulator 32'' which is supported by a bracket 70 mounted near the end of 25 exhaust pipe 20. The electrode 30" may be located axially at or just beyond the end of pipe 20 such that the insulator 32'' need not be mounted with a gas-tight seal. Moreover, the insulator 32 "
may be positioned upstream of the end of pipe 20, 30 to minimize or eliminate soot accumulation thereon.
In yet another possible embodiment (not shown~, the probe electrode might ~e embedded in an annular insulator, which insulator might be inserted into the exhaust duct or form an extension thereto However, in such instance care must be taken to avoid build-up of soot or other conductive deposits on the insulator.
A high degree of electrical isolation between probe 30 and the conductive portions of the duct 20 must be maintained. If the insulator 32 is posi-tioned such that it is exposed to the exhaust gasstream, the potential for soot accumulation on it exists, which may in turn give rise to leakage currents, particularly when damp. To minimize soot accumulation, one, or possibly two shadow shields 80a and 80b in Fig. 3 or 80'a and 80'b in Fig. 4, may be arranged to shadow the surface of the insulator from the direct gas flow.
Whether or not shadow shields are employed, leakage currents involving the probe electrode may be minimized through use of a guard ring. Accord-ingly, the insulator 32 in Fig. 3 and the insulator 32' in Fig. 4 include guard rings 36, 36' respec-tively. Insulator 32 is comprised of an inner cylindrical insulator 32a and a radially outer cylindrical insulator 32b concentric with insulator 32a. The base of annular electrode 30 is fixedly mounted, as by a friction fit or bonding, into inner insulator 32a. The insulator 32 also includes a conductive metal guard ring 36 intermediate and af-fixed to the inner ana outer insulators 32a, 32brespectively. Guard ring 36 is cylindrical and is concentric with insulators 32a, 32b and the por~
tion of probe 30 extending therethrough. The guard ring 36 is operated at substantially the same po-ten;
tial as the probe electrode 30, -thus forming a re-gion within and across the surface of the ceramicwhich is at substantially the same potential as the electrode 3Q. Accordingly, no leakage current can flow across this region. Leakage curren-ts from the surrounding structure of engine 12 and exhaust duct 20 can pass over the outer insulator 32b, via the soot, to the guard ring 36. From the guard ring 36, these leakage currents are shunted to ground and therefore do not arrive at the probe electrode 30.
Further, since the electrode 30 and the guard ring 36 are maintained at subs-tantially the same poten-tial~ no leakage of currents occurs ~etween the guard and the electrode.
Signal developing circuitry 33 is connected in the circuit of probe 30 between the probe and the ground reference potential. Signal developing cir-cuitry 33 includes a current-to-voltage converter 48 and a gain circuit 50. ~ssuming a 1 megohm re-sistor 51 across converter 48, a 1 microampere in-put provides a 1 volt output. Gain circuit 50 may typically have a gain factor of fifty.
In the embodiment illustrated in Fig. 3, the indicator 53 consists of a root mean square (rms) volt meter 54 which is connected to the output of signal developing circuitry 33 to receive the signal voltage as its input.
The output of the rm~ meter 54 may be a visual indication of the root mean square value of the signal occasioned by the passage of successive charged particle packets through the exhaust duct 20. This indication may be calibrated and ex-pressed in terms of the percentage of particulate in the exhaust gas stream or it may be referenced to opacity measurements and expressed as a change in opaci~y in the gas stream~ Alternatively or additionally, with the appropriate time constants applied to the signal~averaging circuitry a sub-stantially DC electrical signal indicative of the average value of particulate in th~ exhaust gas stream may be provided. Those time constants may be provided as function of engine combustion fre-quency. Such an indicating signal may additionally or alternatively he used for various control pur-poses.
The indicating device 53 might alternatively comprise a cathode ray tube (CRT) or similar dis-play device for displaying the output signal from circuitry 33 in a time-resolved rnanner. ~lore specifically, the signal provided by circuitry 33 may comprise the vertical, or Y, input to an X-Y
display in which time is measured along the X axis.
In other words, the pulsations appearing across resistor 5Q as a result of the passage of succes-sive particulate packets in the exhaust gas stream are displayed in a similar time-resolved succession on the face of a display device, as in Figs. 6, 7 and 8.
The signal displays of Figs. 6, 7 and 8 were obtained at a common engine speed and were provided hy connecting the output from the probe 3Q directly to the one megohm impedance at the "~" input of a Tektronics 7~34 oscilloscope. These displays are depicted as the upper trace in each of the Figs~ 6, 7 and 8. A lower trace is also contained in each of those Figs. for illustrating timing signals de-veloped, as for instance, from, and coinciding with, each second top dead center ~TD~ event associated with a particular one of t~le engine cylinders. The TDC signal may be provided in a known manner, as by a magnetic sensor (not shown) detecting a timing mark on the engine flywheel and suppressing the un~
wanted indication of each second TDC event. Al-though those timing signals are shown in time coin-cidence with the peak in the particula-te signals, it will be understood that such is normally not the case because of the delay interval between combus-tion chambers and the position in the exhaust gas stream at which probe 30 is stationed, i.e. phase lag. The upper and lower traces are preferably triggered by scme periodically recurring event in the engine operating cycle, as by the TDC signal constituting the illustrated timing signals men-tioned above, such that the trace pulsations appear relatively stationary. The peaks of the particulate signal on the upper trace have a magnitude of ap-proximately 20~ millivolts and typically represent a current level o several tenths o a micxoampere.
The particulate signals in Fig. 6 resulted for ex-haust gas conditions coinciding with measured opacity levels below about 1%.
Fig. 7 is an illustration similar to Fig. 6 with the only difference being that the particulate-level signals are of substantially greater magnitude ~i9~
- 2a -than those of Fig. 6 and are correspondingly repre-senta~ive of a higher particulate level, i.e. coin-ciding with measured opacity levels of about 13%.
Indeed, the magnitudes of the particulate level signals and measurements from an exhaustdilution tun-nel exhibit good correlation across a broad range of particulate levels~
Fig. 8 deplcts a display of a type similar to that of Figs. 6 and 7, however, it illustrates a difference in the relative particulate levels in the exhaust gas puffs issuing from different com bustion chambers. Specifically, the magnitudes of the particulate level signals or pulses A, C and D from the first, third and fourth cylinders ~not all shown~ in a four cylinder firing sequence are of relatively normal magnitude, whereas the magnitude of the signal B associated with the second cylinder in the sequence is of substantially greater magni-tude. By correlating the successive particulate signals with the respective engine cylinders from which they derive, it is possible to identify the cylinder and combustion chamber in which an abnor-mal particulate level condition arises. Such con-ditions axe generally caused by need for adjustment or repair of a particular one of the fuel injectors 14 and the identification of the offending injector is facilitated by this capability.
Correlation of a particulate packet signal with a particular cylinder and/or injector may be accomplished by "perturbing" the injector such that the "perturbance" appears in the partic~late signal, - 21 ~
then noting i-ts location in the sequence of parti-culate signal pulses and referencing the other pulses of predetermined firing or combustion se-quence thereto. An injector's operation may be "perturbed" by breaking the fuel line to it or by rotating its holder. Such technique is particularly suitable for identifying which of a plurality of injectors may be operating in an abnormal manner and is conveniently performed by repair and service personnel as well as by manufacturing personnel during the original checkout of the engine. It will be understood that in addition to identifying which cylinder and/or injector is malperforming, some indication as to the nature of that malper-formance may also be gained. For ins-tance, the magnitude of the particulate signal may be indi-cative of an e~cess or a shortage of fuel supplied by a particular injector.
It will be understood that the need to perturb an injector to identify its location in a sequence of displayed particulate pulses may he avoided if it is otherwise possible to determine the transport time between any displayed particulate pulse and the combustion chamber from which it issued. Fac-tors such as exhaust system geometry, engine speedengine operating event (i.e. TDC~, engine and/or air temperature, air pressure, etc. would typically be included in such a determination.
As an alternative or supplement to the rms meter 54, the signal provided by probe 30 might be sampled at a relatively high frequency and the samples then averaged to provide a measure of the particulate level.
The probe of the invention is preferably a loop, although other probes may be used. The probe need not be short-circuited on itself (as in ~igure 2).
The probe preferably has little or no electrical contact with the gas stream as described hereinbefore, and thus may take the forms described herein. Alter-natively, it may be totally electrically insulated from the gas stream by virtue of electrical lnsulation or size.
Although this invention has been shown and described with respect to detailed embodiments there-of, it will be understood by those skilled in the art that various changes in form and detail thereof may be made without departing from the spirit and scope of the claimed invention~ For instance, if the insulator which isolates the probe from the ex-haust pipe is sufficiently removed from contact with the exhaust gas, there may be no need for shadow shields and/or guard rings. Moreover, although the fully annular electrode configuration provides cer-tain ad~antages, it will be understood that the probe might be formed of one or more arcuate elec-trodes each extending but a portion of a full circle and electricall~ connected to one another. Moreover, the electrode might be linear and extend into or near the gas stream transverse to its direction of flow. As previously stated, such electrodes will X ,, ~9~
have a relatively small dimension, Q, in the direc-tion of gas flow, but are ~omewhat moxe dependent upon the radial location of charged particles in the exhaust gas stream that were the aforedescribed annular probes.
Claims (21)
1. Apparatus for indicating an operating characteris-tic of a periodically combusting internal combustion engine having duct means defining an exhaust gas path, said engine having an exhaust gas stream issuing in said path in a periodic manner from at least one com-bustion chamber of the engine, said exhaust gas stream containing electrically-charged particles, said charge being of the same polarity on substantially all of the charged particles at a monitoring location along said path, and said periodic combustion and issuance of exhaust gas causing said charged particles to be grouped in respective periodic packets, said apparatus comprising:
electrically conductive, passive electrode means inductively responsive to electrically-charged parti-cles passing thereby, said electrode means being dis-posed in proximity with said exhaust gas stream at the monitoring locating in electrical isolation from said duct means for sensing, principally by the induced image charge, the passage and the charge-quantity of the respective packets of charged particles;
means operatively connected to said electrode means and responsive to the sensed passage and charge-quantity of the particle packets for providing an electrical signal having a series of distinct pulsat-ing components corresponding in time with the passage of respective one of said particle packets and correspond-ing quantitatively with the charge-quantity of the re-spective ones of said particle packets; and means responsive to at least said pulsating com-ponents of said signal for indicating an operating characteristic of the engine.
electrically conductive, passive electrode means inductively responsive to electrically-charged parti-cles passing thereby, said electrode means being dis-posed in proximity with said exhaust gas stream at the monitoring locating in electrical isolation from said duct means for sensing, principally by the induced image charge, the passage and the charge-quantity of the respective packets of charged particles;
means operatively connected to said electrode means and responsive to the sensed passage and charge-quantity of the particle packets for providing an electrical signal having a series of distinct pulsat-ing components corresponding in time with the passage of respective one of said particle packets and correspond-ing quantitatively with the charge-quantity of the re-spective ones of said particle packets; and means responsive to at least said pulsating com-ponents of said signal for indicating an operating characteristic of the engine.
2. The apparatus of Claim 1 wherein the interval be-tween successive packets of charged particles always exceeds a certain distance over the full operating range of the engine and wherein the length of said electrode axially of said exhaust gas stream is less than said certain distance thereby to provide suffi-cient resolution to detect successive individual charged-particle packets.
3. The apparatus of Claim 2 wherein said length of the electrode axially of the exhaust gas stream is substantially less than said certain distance.
4. The apparatus of Claim 1 wherein said electrode is substantially annular and the axis of the annulus is substantially parallel to the axis of the exhaust gas stream thereat.
5. The apparatus of Claim 3 wherein said electrode is substantially annular and coaxial with the exhaust gas stream thereat.
6. The apparatus of Claim 5 wherein the inside diameter of said annular electrode is sufficient to enable the majority of the exhaust gas stream thereat to flow therethrough.
7. The apparatus of Claim 6 wherein the inside diameter of said annular electrode is at least as large as the gas stream thereat.
8. The apparatus of Claim 5 wherein said electrode is mounted in and extends from an insulator, said insula-tor including a surface in communication with said ex-haust gas stream, and including a conductive guard ele-ment disposed in said insulator surface, said guard element encircling and being spaced from said electrode for providing a preferential conductive path for leak-age currents occasioned in any soot deposits on said surface of the insulator.
9. The apparatus of Claim 8 wherein said guard ele-ment and said electrode are each connected substantially independently of one another to substantially the same potential.
10. The apparatus of claim 9 wherein said guard ele-ment and said electrode are each connected to substan-tially ground potential.
11. The apparatus of Claim 9 further including shadow-shielding means interposed between said exhaust gas stream and said flow-contacting surface of said in-sulator to impede the deposition of soot onto the flow-contacting insulator surface from the exhaust gas stream.
12. The apparatus of Claim 1 wherein said engine characteristic indicating means comprises circuit means for providing an output signal corresponding to the particulate emission level of each respective cylinder.
13. The apparatus of Claim 1 wherein said engine characteristic indicating means comprises circuit means for providing an output signal corresponding to the root mean square of the pulsating signal and thereby being indicative of the level of particulate in the exhaust gas stream.
14. The apparatus of Claim 1 wherein said engine characteristic indicating means comprises means for visually displaying the waveform of said signal in-cluding said pulsating components to afford visual analysis thereof.
15. The apparatus of Claim 5 wherein the engine is a multicylinder compression-ignition engine and said engine characteristic indicating means comprises means for visually displaying the waveform of said signal including said pulsating components for a plurality of successive charged particle packets to afford visual comparative analysis thereof.
16. The method of analyzing the relative performance of a fuel injector associated with a respective com-bustion chamber in a diesel engine, said engine having duct means defining an exhaust gas path and an exhaust gas stream issuing in said path in a periodic manner from said combustion chamber, said exhaust gas stream containing electrically-charged particles, said charge being of the same polarity on substantially all of the charged particles at a monitoring location along said path, and said periodic combustion and issuance of ex-haust gas causing said charged particles to be grouped in respective periodic packets, the method comprising:
electrostatically sensing at the monitoring location, principally by the induced image charge, the passage and the charge-quantity of the respec-tive packets of charged particles;
developing an electrical signal from the sensed passage and charge-quantity of each of said charged particle packets said signal having a series of distinct pulsating components corre-sponding in time with said sensed passage of the respective said particle packets and corresponding quantitatively with the charge-quantity of the respective said particle packets; and indicating an operating characteristic of the engine from the pulsating components of the developed signal.
electrostatically sensing at the monitoring location, principally by the induced image charge, the passage and the charge-quantity of the respec-tive packets of charged particles;
developing an electrical signal from the sensed passage and charge-quantity of each of said charged particle packets said signal having a series of distinct pulsating components corre-sponding in time with said sensed passage of the respective said particle packets and corresponding quantitatively with the charge-quantity of the respective said particle packets; and indicating an operating characteristic of the engine from the pulsating components of the developed signal.
17. The method of claim 16 wherein the indicated engine operating characteristic is the particulate emission level.
18. The method of claim 16 wherein said step of in-dicating an operating characteristic of the engine comprises displaying the waveform of the developed signal to afford visual analysis thereof.
19. The method of Claim 16 wherein the step of sens-ing the passage of charged particle packets comprises sensing the passage of charged particles of effective-ly less than one packet thereof at any instant such that said signal waveform provides good resolution of each said particle packet.
20. The method of Claim 19 wherein the step of sens-ing the passage of less than one packet of particles at any instant comprises positioning an electrically conductive, passive annular electrode in proximate substantially coaxial relation with the exhaust gas stream in electrical isolation from said duct means, the axial length of the electrode being substantially less than the distance between successive packets of charged particles.
21. The method of Claim 18 wherein the engine is multi-cylindered, each cylinder having a respective injector, the displayed waveform including at any one time the respective pulsating components corresponding with the particle packets from all of the cylinders in the order of their occurrence, and including the further step of:
perturbing the operation of a predetermined injector sufficiently to cause a noticeable change in one pulse component of the displayed series thereby to identify which of said waveform pulse components corresponds with said predetermined injector.
perturbing the operation of a predetermined injector sufficiently to cause a noticeable change in one pulse component of the displayed series thereby to identify which of said waveform pulse components corresponds with said predetermined injector.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US432,501 | 1982-10-04 | ||
| US06/432,501 US4456883A (en) | 1982-10-04 | 1982-10-04 | Method and apparatus for indicating an operating characteristic of an internal combustion engine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1194116A true CA1194116A (en) | 1985-09-24 |
Family
ID=23716425
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000437704A Expired CA1194116A (en) | 1982-10-04 | 1983-09-27 | Method and apparatus for indicating an operating characteristic of an internal combustion engine |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US4456883A (en) |
| EP (1) | EP0110802B1 (en) |
| JP (1) | JPS5994061A (en) |
| AT (1) | ATE45630T1 (en) |
| AU (1) | AU1985383A (en) |
| CA (1) | CA1194116A (en) |
| DE (1) | DE3380418D1 (en) |
| IN (1) | IN160965B (en) |
| MX (1) | MX158121A (en) |
Families Citing this family (76)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4584531A (en) * | 1982-10-04 | 1986-04-22 | United Technologies Corporation | Noncontact electrostatic hoop probe for combustion engines |
| US4615008A (en) * | 1982-12-22 | 1986-09-30 | United Technologies Corporation | Pulse record data capture for electrostatic engine diagnostics |
| US4617631A (en) * | 1982-12-28 | 1986-10-14 | United Technologies Corporation | Externally discriminated/correlated electrostatic engine diagnostics |
| US4617628A (en) * | 1982-12-28 | 1986-10-14 | United Technologies Corporation | Expandable electrostatic engine diagnostics classifier |
| US4617629A (en) * | 1982-12-28 | 1986-10-14 | United Technologies Corporation | Expanded classification sample in electrostatic engine diagnostics |
| US4578756A (en) * | 1982-12-28 | 1986-03-25 | United Technologies Corporation | Adaptive electrostatic engine diagnostics |
| US4586139A (en) * | 1982-12-28 | 1986-04-29 | United Technologies Corporation | Normalizing engine wear indication with R.M.S. noise |
| US4617632A (en) * | 1982-12-28 | 1986-10-14 | United Technologies Corporation | Waveform discriminated electrostatic engine diagnostics |
| US4587614A (en) * | 1982-12-28 | 1986-05-06 | United Technologies Corporation | System fault detection in electrostatic flow diagnostics |
| US4590562A (en) * | 1982-12-28 | 1986-05-20 | United Technologies Corporation | Statistically correlated electrostatic engine diagnostics |
| US4607337A (en) * | 1982-12-28 | 1986-08-19 | United Technologies Corporation | Interprobe electrostatic engine diagnostics correlation |
| US4595987A (en) * | 1982-12-28 | 1986-06-17 | United Technologies Corporation | Contiguous event discrimination in electrostatic engine diagnostics |
| US4625280A (en) * | 1982-12-28 | 1986-11-25 | United Technologies Corporation | Sectional distress isolating electrostatic engine diagnostics |
| US4604702A (en) * | 1982-12-28 | 1986-08-05 | United Technologies Corporation | Variable discriminators in electrostatic engine diagnostics |
| US4617630A (en) * | 1982-12-28 | 1986-10-14 | United Technologies Corporation | System fault discriminating electrostatic engine diagnostics |
| US4573123A (en) * | 1982-12-28 | 1986-02-25 | United Technologies Corporation | Electrostatic engine diagnostics with acceleration related threshold |
| DK150225C (en) * | 1984-05-30 | 1987-07-06 | Niels Hvilsted | HYDRAULIC CYLINDER EQUIPPED TO RECOVER AT LEAST ONE ELECTRIC POSITIONER |
| US4724394A (en) * | 1985-10-11 | 1988-02-09 | Brunswick Corporation | Gas detection by ion mobility segregation |
| DE3701934A1 (en) * | 1987-01-23 | 1988-08-04 | Beru Werk Ruprecht Gmbh Co A | Ion-flow probe |
| GB8707187D0 (en) * | 1987-03-25 | 1987-04-29 | Hughes Ltd Stewart | Monitoring of foreign object in engines |
| DE3907387A1 (en) * | 1989-03-08 | 1990-09-13 | Singer Hermann | METHOD FOR MEASURING PARTICLES IN POLYDISPERSE SYSTEMS AND OF PARTICLE CONCENTRATIONS OF MONODISPERS AEROSOLS AND MEASURING DEVICE FOR IMPLEMENTING THE METHOD |
| US4939466A (en) * | 1989-04-10 | 1990-07-03 | Board Of Control Of Michigan Technological University | Method and apparatus for sensing the regeneration of a diesel engine particulate trap |
| CH680238A5 (en) * | 1989-12-04 | 1992-07-15 | Matter & Siegmann Ag | |
| GB2277154B (en) * | 1993-04-06 | 1997-06-25 | Pollution Control & Measuremen | Method and apparatus for detecting particles in a flow |
| DE4311546A1 (en) * | 1993-04-07 | 1995-01-19 | Emmanuel Dr Rer Nat Bisse | Use of colloidal silicon dioxide for the treatment of sickle cell anemia, malaria and exogenously induced leukopenias |
| US5552711A (en) * | 1994-11-10 | 1996-09-03 | Deegan; Thierry | Turbine engine imminent failure monitor |
| GB2335745B (en) * | 1998-03-27 | 2003-04-09 | Pcme Ltd | Improvements in and relating to particle detectors |
| GB2336434A (en) * | 1998-04-17 | 1999-10-20 | Stewart Hughes Ltd | An apparatus for and method of monitoring a rotating machine |
| DE19838223C2 (en) * | 1998-08-22 | 2003-02-06 | Daimler Chrysler Ag | Method for determining the ion content after a combustion process in a self-igniting internal combustion engine |
| US6238122B1 (en) * | 1999-03-01 | 2001-05-29 | Exhaust Etiquette | Display device and method therefor |
| LU90495B1 (en) * | 1999-12-24 | 2001-06-25 | Delphi Tech Inc | Device and method for ion current sensing |
| US6394062B2 (en) * | 2000-03-30 | 2002-05-28 | Siemens Canada Limited | Dust sensing assembly air intake system |
| FI118278B (en) * | 2003-06-24 | 2007-09-14 | Dekati Oy | Method and sensor device for measuring particulate emissions from combustion engine exhaust |
| US7743606B2 (en) * | 2004-11-18 | 2010-06-29 | Honeywell International Inc. | Exhaust catalyst system |
| US7182075B2 (en) * | 2004-12-07 | 2007-02-27 | Honeywell International Inc. | EGR system |
| US7467614B2 (en) | 2004-12-29 | 2008-12-23 | Honeywell International Inc. | Pedal position and/or pedal change rate for use in control of an engine |
| US7165399B2 (en) * | 2004-12-29 | 2007-01-23 | Honeywell International Inc. | Method and system for using a measure of fueling rate in the air side control of an engine |
| US7275374B2 (en) * | 2004-12-29 | 2007-10-02 | Honeywell International Inc. | Coordinated multivariable control of fuel and air in engines |
| US7591135B2 (en) * | 2004-12-29 | 2009-09-22 | Honeywell International Inc. | Method and system for using a measure of fueling rate in the air side control of an engine |
| US7328577B2 (en) | 2004-12-29 | 2008-02-12 | Honeywell International Inc. | Multivariable control for an engine |
| US20060168945A1 (en) * | 2005-02-02 | 2006-08-03 | Honeywell International Inc. | Aftertreatment for combustion engines |
| US7752840B2 (en) * | 2005-03-24 | 2010-07-13 | Honeywell International Inc. | Engine exhaust heat exchanger |
| US7469177B2 (en) * | 2005-06-17 | 2008-12-23 | Honeywell International Inc. | Distributed control architecture for powertrains |
| US7389773B2 (en) | 2005-08-18 | 2008-06-24 | Honeywell International Inc. | Emissions sensors for fuel control in engines |
| US7155334B1 (en) | 2005-09-29 | 2006-12-26 | Honeywell International Inc. | Use of sensors in a state observer for a diesel engine |
| US7765792B2 (en) * | 2005-10-21 | 2010-08-03 | Honeywell International Inc. | System for particulate matter sensor signal processing |
| US7357125B2 (en) * | 2005-10-26 | 2008-04-15 | Honeywell International Inc. | Exhaust gas recirculation system |
| US7628007B2 (en) * | 2005-12-21 | 2009-12-08 | Honeywell International Inc. | Onboard diagnostics for anomalous cylinder behavior |
| US20070144149A1 (en) * | 2005-12-28 | 2007-06-28 | Honeywell International Inc. | Controlled regeneration system |
| US7415389B2 (en) * | 2005-12-29 | 2008-08-19 | Honeywell International Inc. | Calibration of engine control systems |
| FR2899330B1 (en) * | 2006-03-31 | 2008-06-20 | Haliaetus Technologies Soc Par | DEVICE FOR TESTING AN EXHAUST LINE OR SIMILAR |
| FR2916250B1 (en) * | 2007-05-14 | 2010-08-27 | Renault Sas | CONNECTING A TURBOCHARGER WITH AN OXIDATION CATALYST OF AN EXHAUST LINE OF AN INTERNAL COMBUSTION ENGINE |
| US8060290B2 (en) | 2008-07-17 | 2011-11-15 | Honeywell International Inc. | Configurable automotive controller |
| US8620461B2 (en) | 2009-09-24 | 2013-12-31 | Honeywell International, Inc. | Method and system for updating tuning parameters of a controller |
| FIU20100090U0 (en) * | 2010-02-25 | 2010-02-25 | Pegasor Oy | Exhaust gas sensor |
| US8504175B2 (en) | 2010-06-02 | 2013-08-06 | Honeywell International Inc. | Using model predictive control to optimize variable trajectories and system control |
| GB201113478D0 (en) * | 2011-08-04 | 2011-09-21 | Cambridge Entpr Ltd | Sensing systems |
| US9677493B2 (en) | 2011-09-19 | 2017-06-13 | Honeywell Spol, S.R.O. | Coordinated engine and emissions control system |
| US9650934B2 (en) | 2011-11-04 | 2017-05-16 | Honeywell spol.s.r.o. | Engine and aftertreatment optimization system |
| US20130111905A1 (en) | 2011-11-04 | 2013-05-09 | Honeywell Spol. S.R.O. | Integrated optimization and control of an engine and aftertreatment system |
| KR101305198B1 (en) * | 2011-12-09 | 2013-09-26 | 현대자동차주식회사 | Particulate matters sensor unit |
| JP2014118968A (en) * | 2012-12-17 | 2014-06-30 | Hyundai Motor Company Co Ltd | Particulate material sensor unit |
| EP3051367B1 (en) | 2015-01-28 | 2020-11-25 | Honeywell spol s.r.o. | An approach and system for handling constraints for measured disturbances with uncertain preview |
| EP3056706A1 (en) | 2015-02-16 | 2016-08-17 | Honeywell International Inc. | An approach for aftertreatment system modeling and model identification |
| EP3091212A1 (en) | 2015-05-06 | 2016-11-09 | Honeywell International Inc. | An identification approach for internal combustion engine mean value models |
| EP3734375B1 (en) | 2015-07-31 | 2023-04-05 | Garrett Transportation I Inc. | Quadratic program solver for mpc using variable ordering |
| US10272779B2 (en) | 2015-08-05 | 2019-04-30 | Garrett Transportation I Inc. | System and approach for dynamic vehicle speed optimization |
| US10415492B2 (en) | 2016-01-29 | 2019-09-17 | Garrett Transportation I Inc. | Engine system with inferential sensor |
| US10036338B2 (en) | 2016-04-26 | 2018-07-31 | Honeywell International Inc. | Condition-based powertrain control system |
| US10124750B2 (en) | 2016-04-26 | 2018-11-13 | Honeywell International Inc. | Vehicle security module system |
| US11199120B2 (en) | 2016-11-29 | 2021-12-14 | Garrett Transportation I, Inc. | Inferential flow sensor |
| KR20180065318A (en) * | 2016-12-07 | 2018-06-18 | 현대자동차주식회사 | Chip type sensor for measuring particulate matter |
| CN106769739B (en) * | 2017-01-19 | 2024-01-23 | 兰州大学 | System for determining percentage of haze charged particles |
| US11057213B2 (en) | 2017-10-13 | 2021-07-06 | Garrett Transportation I, Inc. | Authentication system for electronic control unit on a bus |
| AT523591B1 (en) * | 2020-02-26 | 2022-06-15 | Avl Ditest Gmbh | Device and method for measuring properties of a fluid |
| CN112627941B (en) * | 2021-01-27 | 2022-06-10 | 哈尔滨艾瑞排放控制技术股份有限公司 | Embedded utilize electrostatic adsorption to purify automobile exhaust's device |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3114877A (en) * | 1956-10-30 | 1963-12-17 | Gen Electric | Particle detector having improved unipolar charging structure |
| US3038118A (en) * | 1958-07-21 | 1962-06-05 | Wesix Electric Heater Co | Ion collecting and measuring apparatus |
| US3359796A (en) | 1964-01-23 | 1967-12-26 | Univ Illinois | Apparatus for measuring mass flow using a shielded probe |
| IL22673A (en) | 1964-12-27 | 1968-06-20 | Jaffe A | Sensitive smoke and fire detector |
| US3447071A (en) * | 1965-09-22 | 1969-05-27 | Webb James E | Probes having guard ring and primary sensor at same potential to prevent collection of stray wall currents in ionized gases |
| US3449667A (en) * | 1966-05-18 | 1969-06-10 | Gourdine Systems Inc | Electrogasdynamic method and apparatus for detecting the properties of particulate matter entrained in gases |
| US3526828A (en) | 1967-08-07 | 1970-09-01 | Univ Minnesota | Method and apparatus for measuring particle concentration |
| US3586468A (en) * | 1968-09-16 | 1971-06-22 | A E Gosselin Engineering Inc | Burner combustion control including ultrasonic pressure waves |
| GB1356565A (en) | 1970-09-04 | 1974-06-12 | Ricardo & Co Engineers | Limitting exhaust smoke emission from i c engines |
| US3763428A (en) * | 1971-11-26 | 1973-10-02 | Varian Associates | Simultaneous measurement of the size distribution of aerosol particles and the number of particles of each size in a flowing gaseous medium |
| US3956928A (en) * | 1975-04-28 | 1976-05-18 | Ford Motor Company | Vortex shedding device for use in measuring air flow rate into an internal combustion engine |
| DE2554988C2 (en) * | 1975-12-06 | 1985-01-10 | Robert Bosch Gmbh, 7000 Stuttgart | Method for determining the composition of the operating mixture fed to an internal combustion engine or the combustion sequence of the operating mixture and device for carrying out the method |
| US4249131A (en) * | 1979-04-11 | 1981-02-03 | The United States Of America As Represented By The Secretary Of Commerce | Method and apparatus for measuring electrostatic charge density |
-
1982
- 1982-10-04 US US06/432,501 patent/US4456883A/en not_active Expired - Lifetime
-
1983
- 1983-09-27 CA CA000437704A patent/CA1194116A/en not_active Expired
- 1983-10-01 IN IN1211/CAL/83A patent/IN160965B/en unknown
- 1983-10-03 EP EP83630165A patent/EP0110802B1/en not_active Expired
- 1983-10-03 AT AT83630165T patent/ATE45630T1/en not_active IP Right Cessation
- 1983-10-03 AU AU19853/83A patent/AU1985383A/en not_active Abandoned
- 1983-10-03 DE DE8383630165T patent/DE3380418D1/en not_active Expired
- 1983-10-04 JP JP58186671A patent/JPS5994061A/en active Granted
- 1983-10-04 MX MX199002A patent/MX158121A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| AU1985383A (en) | 1984-04-12 |
| DE3380418D1 (en) | 1989-09-21 |
| IN160965B (en) | 1987-08-22 |
| JPS5994061A (en) | 1984-05-30 |
| EP0110802A2 (en) | 1984-06-13 |
| ATE45630T1 (en) | 1989-09-15 |
| MX158121A (en) | 1989-01-09 |
| EP0110802B1 (en) | 1989-08-16 |
| US4456883A (en) | 1984-06-26 |
| JPH0376706B2 (en) | 1991-12-06 |
| EP0110802A3 (en) | 1985-01-23 |
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