DE3831449A1 - Electronic operational control system for a drive train of a motor vehicle - Google Patents

Abstract

An electronic operational control system for a drive train of a motor vehicle is proposed. The vehicle is operated automatically under the open-loop and closed-loop control of an electronic system (13 and 101 and 131) and is virtually only determined in accordance with predictive actuation of the accelerator pedal (20), the brake pedal (23) and the engine brake element (28) by the driver taking into account the conditions of the terrain or road directly ahead. The driver is consequently relieved of any gear-changing operations and can therefore concentrate completely on the route and the traffic. <IMAGE>

Description

The invention relates to an electronic operating control system stem for a motor vehicle drive train with features according to the preamble of claim 1.

This operating control system serves the driver's request corresponding and the operating state of the vehicle taking into account and the topography of the terrain / road to achieve adapted optimized gear shifting.

For vehicle transmissions with power shift and upstream Converter was sufficient because of the relatively few gears or shifting stages (4 to 7) usually a shift strategy that at Exceeding a certain speed limit one gear switches up or falls below a certain level Speed limit switches down a gear.

However, modern transmissions, especially those for commercial vehicles witnesses have up to 16 gears that formwork to interrupt the load be tested, d. that is, the clutch is opened, then the gear changed and then the clutch closed again. Out From the point of view of practical driving, it becomes clear that for optimal switching, especially in topographical difficult terrain the above mentioned, turning Switching strategy based on number limits is not sufficient can be.  

Such modern transmissions were already the basis of the powertrain management system known from DE-OS 35 26 671. This system is based on the principle that the drive train components - drive motor, clutch, gearbox - are usually supplied by the respective manufacturer together with their own control electronics, which take into account the manufacturer-specific conditions and functionally adapt them to the characteristics of the respective assembly is. In the known system, the drive motor is therefore assigned its own engine electronics, the clutch has its own clutch electronics and the gearbox has its own gear electronics. These aggregate-specific control electronics are functionally superordinated to a master computer, which intervene in the regulation and control of the subordinate electronics and thereby, their mode of operation, can influence the output of the control command. In detail, the electronics of the known solution have the following functions, which are explained in more detail below.

Engine electronics

This consists of a microprocessor, program memory, Data storage, input and output peripherals. It regulates and controls the function of the drive motor after a festge program depending on the measurement or status message len, such as accelerator pedal position, engine temperature, charge air pressure, Speed, clutch position and the like.  

Coupling electronics

This also consists of a microprocessor, program memory, data storage, input and output periphery. You're right applies and controls the function of the clutch after a fixed program, depending on the measurement or status message len, such as engine speed, gear speed, clutch temperature structure and the like.

Transmission electronics

This also consists of a microprocessor, program and data storage, input and output peripherals. It regulates and controls the transmission function according to a set Program, depending on measurement or status signals, such as Engine speed, speed and the like. Up to one To a certain extent, this transmission electronics was already in the Able to implement an automatic shift strategy.

The function of these three unit-specific electronics nell superordinate host computer also consists of egg microprocessor, program memory, data storage, input and Output periphery and served the following purpose: He calculated according to a fixed program setpoints based on Da ten that the three unit-specific electronics in their Linking was not available. Calculate with these The nominal values were any different control orders corrected the aggregate-specific electronics.

With the known drive management system, partially automated driving was therefore possible.

In contrast, the invention has the task of a loading drive control system for the drive train of a motor vehicle create stuff that is able to change one changing operating conditions and topographical conditions Taking account of and taking into account the driver's request to enable predictive driving.

This object is according to the invention through an operating tax System with features according to claim 1 solved.

Due to the concept of electronics according to the invention in the vehicle to a conventional gear shift completely to be dispensed with. The operation of the vehicle is directed practically only after the terrain apron visual predictive actuation of the accelerator pedal, the Brake pedals and the engine brake actuator. The Fah rer is relieved of any switching work, he can concentrate fully on the route and the traffic.

Details of the invention are in the subclaims specified.

The following is the operation control system according to the invention based on three examples shown in the drawing games explained. The drawing shows:

Fig. 1 in principle a motor vehicle drive train in conjunction with a first embodiment of the operation control system according to the invention,

FIG. 1a, in principle, the engine electronics in the construction Betriebssteuersy stem of FIG. 1 used,

FIG. 1b, in principle the coupling electronics in the construction Betriebssteuersy stem of FIG. 1 used,

FIG. 1c, in principle, the transmission electronics in the construction Betriebssteuersy stem of FIG. 1 used,

Fig. 1d, in principle, the structure of the driving operation when Leit Betriebssteuersy stem of FIG. 1 used electronics,

Fig. 2, in principle, a motor vehicle drive train in conjunction with a second embodiment of the operation control system according to the invention,

Fig. 2a, in principle, the construction of one of the three in the operation control system according to Fig. 2 existing aggregate-specific electronics, which from that of the other two different electronic units,

Fig. 3 in principle a motor vehicle drive train in connection with a third embodiment of the operating control system according to the invention, and

Fig. 3a shows the basic structure of the operation control system of FIG. 3.

In the figures are the same or corresponding construction Parts or parts thereof for the sake of clarity Chen provided reference numerals.  

The drive train of a motor vehicle consists of an internal combustion engine serving as the drive motor 1 with an associated fuel injection pump 2 , a transmission 3 and a clutch 4 provided between the latter and the drive motor 1 . The latter is preferably designed as a dry clutch. The delivery quantity adjustment element of the injection pump 2 is designated 5 and the electrically triggered actuation element of the clutch 4 is designated 6 . The gear 3 has a comparatively large number of different gear stages with, for example, 16 shiftable gears. Each gear is switched by interrupting the opening and closing of the clutch 4 , via internal pneumatic, hydraulic or electro-mechanical actuators, the actuation of which depends on the switching state associated with electrically controlled Schaltor gans, which are summarized on the transmission 3 in a switchgear 7 . An axle drive train 9 is connected to the output shaft 8 of the transmission 3 . In the case of FIG. 1 and 2 is associated with a unit specific electronics each of the units 1, 3, 4 of the drive train. The engine electronics are designated 10 , the clutch electronics 11 and the transmission electronics 12 . In the case of FIG. 1, these three electronics 10 , 11 , 12 are functionally superordinate to a driving operation control electronics 13 , while the embodiment according to FIG. 2 manages without these control electronics 13 , but whose function is grafted onto one of the three electronics 10 , 11 or 12 is. In the illustrative case, see Fig. 2a, this is the engine electronics, which is not designated there with 10 , but with 101 because of its additional function. The electronics 10 and 101 , 11 , 12 and - if available - also 13 form in the case of the execution examples according to FIGS. 1 and 2 each participant of a data communication system in the vehicle. Common data transmission element is a possibly redundant serial data bus 14 to which the subscribers 10 or 101 , 11 and 12 and possibly also 13 are connected and can send and receive data or commands via this. In the case of FIG. 3, there is only a single driving operation control electronics 131 in which the functions of the electronics 10 , 11 , 12 and 13 are summarized.

Each of the electronics 10 or 101 , 11 , 12 , 13 or 131 is connected to sensors or status indicators, which supply the data necessary for program processing. In addition, both the engine electronics 10 and the electronics 101 and 131 are each via a command and signal line 15 with the delivery rate 5 of the injection pump 2 in connection. The clutch electronics 11 and the electronics 131 are connected via a command and signaling device 16 to the actuator 6 of the clutch 4 . The transmission electronics 12 and the electronics 131 are via a command and signal line 17 with the switching system 7 of the transmission 3 in connection. At the gear electronics 12 and the electronics 131 a command line 18 is also connected, via which a command as an actuating signal, the actuating device of an engine brake 19 (realized by throttle valve in the exhaust system of the drive engine 1 ) and as a signal to the engine electronics 10 or a memory Electronics 131 is conductive.

With 20 the accelerator pedal, with 21 the associated position sensor and with 22 the outgoing signaling line. 23 is the brake pedal, 24 the associated position transmitter and 25 the outgoing signaling line.

The operating mode selector switch is designated by 26 , on which the driver can preselect the desired operating mode by actuating a switch labeled with one of the characters R , N , D , -, M , +. Here means

R = reverse travel
N = zero / idle position
D = automatic mode
- = manual downshift
M = manual operation
+ = manual upshift

The operating mode selected by actuating the switch marked R or D or M is reported to the transmission electronics 12 or the electronics 131 via a signal line 27 .

28 denotes the motor brake element to be actuated by the driver, 29 the associated detector and 30 the signal line which leads from the latter and leads to the transmission electronics 12 or electronics 131 .

The driver is symbolically indicated in the drawing by a box 31 . The driver's influence on driving pedal 20 , brake pedal 23 , mode selector switch 26 and engine brake member 28 are indicated by arrows 32 , 33 , 34 and 35 sym bolisch.

The four electronics 10 , 11 , 12 , 13 according to FIG. 1 and two of the three electronics 10 , 11 , 12 according to FIG. 2 are in principle each constructed identically. Identical parts of these electronics are indicated in the drawing after the reference symbols of the respective electronics, each with the same capital letter, the meaning of which is explained below.

A designates a microprocessor (CPU) as a central computer.
B denotes a data store.
C denotes a program memory.
D denotes an input periphery, including an input unit, analog / digital converter and input protection circuit.
E denotes an output periphery, including output unit, digital / analog converter, power amplifier and output protection circuit.
F denotes a possibly redundant coupler for serial transmission and reception of data.
G denotes the line connection between coupler F and data bus 14 .
H denotes an electronic monitoring unit called "watchdog", which monitors the functions of the microprocessor A and, in the event of any malfunctions, switches over to redundant systems and triggers an alarm signal.

In the case of FIG. 2, the function of electronic control electronics 13 is omitted, the function of one of the electronics 10 or 11 or 12 is grafted onto the drive. As already mentioned above, the engine electronics designated 101 because of its expanded shape is selected. As shown in FIG. 2a, this has the same basic structure as the electronics 10 , 11 , 12 or 13 , but is supplemented or expanded by additional organs, namely a program memory K and a data memory L.

The driving control electronics 131 of FIG. 3 based on the electronics 101 of FIG. 2, but does not require the coupler F or the line G, but is via the lines 15, 16, 17 of the directly with the above-mentioned components 5, 6 and 7 Drive train connected. In addition, compared to that of FIG. 2, the electronics 131 are supplemented by a few data memories 131 M , 131 N and program memories 1310 , 131 P , as can be seen from FIG. 3a.

The table below shows the most important measured values or status signals, which are detected by sensors or detectors and fed to the electronics 10 or 101 , 11 , 12 , 13 or 131 and in this or these as the basis for program-based processing be used. Here means signal

a = speed of the drive motor 1
b = input speed of gear 3
c = output speed of gear 3 (= speed)
d = position of accelerator pedal 20
e = kick-down actuation of accelerator pedal 20
f = actuation of the brake pedal 23
g = actuation of the engine brake element 28
h = actual position of clutch 4 (open, closed or sliding)
i = actuation of clutch 4
j = switching state of switches that indicate or signal the given states internally of the gearbox 3
k = Setpoint specification of injection quantity at injection pump 2
l = actual value of the fuel injection quantity
m = temperature of the fuel
n = charge air pressure
o = air temperature
p = cooling water temperature
q = shift state of transmission 3 (current gear)
r = temperature of clutch 4 .

Which electronics which which of these signals is supplied is exactly ersicht Lich from FIGS . 1a, 1b, 1c, 1d, 2a and 3a, however, only partially indicated in FIGS . 1, 2 and 3. The signal introduction into the input periphery of the respective electronics is indicated by the arrows marked with corresponding lower case letters.

The motor electronics 10 receives the signals a , c , d , e , f , g , i , l , m , n , o and p via the input periphery 10 D and the signal k via the data bus 14 as a working basis - see FIG. 1a. The coupling electronics 11 receives the signals a , b , c , h , l and r as input base via the input peripheral 11 D and the signals 1 and 9 via the data bus 14 - see FIG. 1b. The transmission electronics receives the signals a , b , c , d , e , f , g and j as a working basis via the input periphery 12 D and the signal h via the data bus 14 - see FIG. 1c. The driving operation control electronics 13 receives the signals a , c , d , e , f , g , l and q as a working basis - see FIG. 1d.

The electronics, which in the case of FIG. 2 the function of the omitted driving control electronics 13 is grafted on, must operate with the same signals a , c , d , e , f , g , l and q and for an aggregate-specific loading necessary additional signals are supplied. In the selected example according to FIG. 2a, these are the signals m , n , o and p .

The driving operation control electronics 131 according to FIGS . 3, 3a receive all signals a to r .

The motor electronics 10 according to FIG. 1 and the electronics 101 according to FIG. 2 regulate and control the function of the drive motor 1 in accordance with a program defined in the program memory 10 C or 101 C depending on the measurement signals supplied to it. In this case, data are written into or retrieved from the data memory 10 B or 101 B. In the case of FIG. 3, 3a, the regulation and control of the operation of the engine 1 according to one example, 131 C introduced in the program memory program written by calculation processes of the micropro zessors 131 A on the basis of supplied measurement signals. Data is retrieved, for example, in the data memory 131 B is cried ben or therefrom. As a result, in each of the cases there is a setting of the fuel injection quantity that is necessary for the specific driving situation by issuing commands via line 15 for a corresponding adjustment of the delivery quantity adjustment element 5 of the injection pump 2 .

The clutch electronics 11 according to FIGS. 1 and 2 regulates and controls the function of the clutch 4 according to a program defined in the program memory 11 C depending on the measurement signals to be fed to it. In the case of Fahrbetriebssteuerelek electronics 131 of FIG. 3, 3a is carried out, the Regulation and control tion of the function of the clutch 4 according to one example registered in the program memory 1310 program by loading the operations of the microprocessor 131 A on the basis of measurement signals to be guided. For example, data is written in the space A Since 131 M or retrieved from. The result is a corresponding de influence on the clutch 4th in each of the cases. Commands for a relevant actuation are issued via line 16 to actuator 6 .

Regulates the transmission electronics 12 according to Fig. 1 and 2 and controls the operation of the transmission 3 according to a memory in the program 12 C set program depending on the supplied measurement signals. In the case of the driving operation control electronics 131 according to FIGS . 3, 3a, the regulation and control of the function of the transmission 3 is carried out according to a program, for example, written in the program memory 131 P by calculations by means of the microprocessor 131 A on the basis of supplied measurement signals. For example, data is written in the space A 131 N Da or retrieved from. As a result, a gear shift that is specific to the driving situation is obtained by issuing corresponding commands via line 17 to switchgear 7 of transmission 3 .

Both the driving operation control electronics 13 according to FIG. 1 and the extended electronics 101 according to FIGS. 2, 2a each have a multiple function. In a first function, which is superordinate to that of the normal function of the electronics 10 , 11 , 12 , the electronics 13 or 101 intervenes in a regulating and controlling manner in the function of the electronics 10 , 11 , 12 or other electronics. Data is used that is not available to the individual electronics in their connection. By a program memory 13 D and 101 K stored program are thereby calculated on the basis of said data set values via the data bus 14 to the other electronic units 10, 11, 12 (Fig. 1) or 11, 12 (Fig. 2) be communicated and correct the setpoints calculated by the programs there - as far as necessary or deviating. In the case of the driving operation control electronics 131 according to FIGS . 3, 3a, this setpoint correction function is fulfilled by a program, for example written in the program memory 131 K , by means of a calculation by the microprocessor 131 A on the basis of the said data. Relevant data are, for example, written into the data memory 131 L and can be retrieved from it.

In addition, at least one further program is written into a further or already existing program memory in the driving operation control computer 13 according to FIG. 1, 1d, also in the extended electronics 101 according to FIG. 2, 2a and also also in the driving operation control electronics 131 according to FIG. 3, 3a , which is used to realize a predictive operating mode of the vehicle with a topography of the terrain of gear shift and engine torque control that the driver ( 31 ) preselected by the operating mode selector switch 26 by appropriate predictive actuation of the accelerator pedal 20 and / or brake pedal 23 and / or engine brake member 28 initiated.

In order to be able to correctly detect the desired mode of operation of the vehicle, the driving operation control electronics 13 (in the case according to FIG. 1) or the extended electronics 101 (in the case according to FIG. 2) or the driving operation control electronics 131 (in the case according to FIG. 3 ) have the following knowledge:

• a) How heavy or what mass the vehicle currently has, if available with towed trailer or semi-trailer?
• b) In what topographical conditions was this Vehicle in a recent period?  
• c) Which terrain (level, incline, slope) becomes current drive on?
• d) What is the condition of the currently used area, the busy road?
• e) What is the driver's wish regarding driving behavior tens of his vehicle?

This level of knowledge is based on calculation by program the basis of supplied measurement or status signals guided. The measured data supplied by pro grammatically controlled calculation with the following values telt, namely

• - the acceleration of the vehicle - by deriving the speed (output speed of the transmission 3 = signal c ) over time
• - The torque delivered to the crankshaft of the drive motor 1 in traction or in overrun mode - from the quantity of fuel introduced into the drive motor 1 (= signal 1 ) and the speed of the drive motor 1 (= signal a ) in conjunction with a data memory 13 B or 101 B or 131 B stored characteristic map of the drive motor 1 ,
• - The driving resistance acting on the vehicle from the outside against the direction of travel, such as gradients, headwinds and the like - from the previously calculated engine torque and the previously calculated vehicle acceleration, taking into account the vehicle mass and the translation ratios in the transmission 3 and final drive train 9 ,
• - The external forces in the direction of travel act on the accelerating forces, such as downhill, tailwind and the like - from the previously calculated engine torque, the pre-calculated vehicle acceleration and the braking torque applied by the engine brake (= signal g ) and service brake (= signal f ) taking into account the vehicle mass and the transmission ratios in the transmission be 3 and final drive train 9 ,
• - The mass of the vehicle - by averaging from several mass calculations, after the previous stop under the assumption "start in level" is carried out, on the basis of the engine torque and the vehicle acceleration taking into account the translation ratios in the transmission 3 and Drive train 9 (in order to accelerate this mass-mean value calculation or to reduce the number of start-up processes required for this, the electronics 13 or 101 or 131 can be given a “start value” of the mass. This mass start value can by weighing the vehicle or by means of sensors from the loading of the vehicle under addition of the known vehicle curb weight and who is then included in said average calculation),
• - the gradient of the terrain / road before stopping - from the values of the tractive force, the acceleration and the mass of the vehicle,
• - The speed at which the accelerator pedal is actuated - by deriving the accelerator pedal movement between two signaled resting states (= signals d ) over time.

The desired forward-looking driving style is realized in that measured values from the electronics 13 or 101 or 131 in the past and data calculated therefrom, as described above, are stored and used when the driver changes the accelerator pedal position with a corresponding movement dynamic signals the desire for a change in driving mode. It is assumed that at least one practiced driver intuitively moves the accelerator pedal and, through the actuation speed with which he moves the pedal, reflects the traffic situation in front of him in his field of vision. Various examples of such traffic situations are explained in more detail below:

Case 1: Starting after a previous stop:

In this case, the driver must first indicate to the electronics 13 or 101 or 131 whether the vehicle is e.g. B. after a traffic light stop to be accelerated normally, or whether the vehicle z. B. for maneuvering or moving up after a traffic jam on the route should only be accelerated relatively slowly. This desired operation is recognized by the electronics 13 or 101 or 131 based on the amount of the accelerator pedal position and the duration of this movement. If this movement is correspondingly slow, the driver's desire for creeper travel or maneuvering is recognized and implemented in a command to engage a necessary small gear in the transmission 3 . The exit from the shunting or crawl gear operation takes place when the currently engaged gear is greater than or equal to that of the external force-calculated gear for normal starting.

On the other hand, if the accelerator pedal movement is relatively fast and wide, this is recognized as the driver's wish for normal starting and converted into a command for engaging the gear calculated for normal starting in transmission 3 . For this start-up, the value of the slope calculated and stored before the stop is called up for the calculation of the necessary tractive force and the necessary starting gear is calculated by the electronics 13 or 101 or 131 and a corresponding command - in the case according to FIGS. 1 and 2 via the transmission electronics 12 , in the case of FIG. 3 directly - output via line 17 to the switching device 7 of the transmission 3 and there prompted the engagement of the calculated gear. In addition, the actuator 6 of the clutch 4 - in the case of FIGS. 1 and 2 via the clutch electronics 11 , in the case of FIG. 3 directly - via the line 16 receives a command so that the starting gear can be engaged with the clutch open. This automatic insertion of the precalculated starting gear takes place only when the driver wishes the "automatic driving operation" is signaled by operating the switch D of the operating mode selector switch 26 . This automatic engagement of the calculated starting gear does not take place if the switch M (for manual switching) is actuated in the operating mode selector switch 26 . In this case, first gear is selected. If afterwards the switch D is actuated again, the engaged gear remains in place until a change of gear is initiated by the electronics 13 or 101 or 131 due to the automatic which is now effective again. For starting, a command is also issued - in the case of FIG. 1 via the engine electronics, in the case of FIGS. 2 and 3 directly - via line 15 to the delivery rate adjustment element 5 of an injection pump 2 and this starting from the idle position proportional to the position of the accelerator pedal 20 adjusted to get the desired engine torque.

Case 2: Driving in the plain:

If the vehicle is in motion after starting, a distinction is made between "choosing the gear" and "executing the gearshift". The gear is selected on the basis of the vehicle acceleration, and gears can also be skipped if necessary. The acceleration values are stored in a preprogrammed manner in the electronics 13 or 101 or 131 for all conceivable and possible operating states. The design of the circuit, on the other hand, is tied to exceeding or falling below the limit speeds, the values of which are also pre-programmed in the electronics 13, 101 and 131, respectively. These limit speeds can also be variably pre-programmed depending on certain targets. For example, in the event that a consumption-optimized driving style is sought, partial loads can be switched earlier, for which case the upper speed limit is set lower than normal. In addition, a limited exceeding of the speed limit at full load can be stored as pre-programmed as permissible, in the event that the vehicle can no longer be accelerated in higher gear. The execution of a circuit is also omitted if the electronics 13 or 101 or 131 he knows that the speed of the vehicle could not be maintained after inserting the pre-calculated gear. A new gear (applies to both upshifting and downshifting) is therefore only engaged if the current driving speed could be maintained after engagement. For this purpose, the electronics 13 or 101 or 131 calculates the acceleration from the already determined value of the gradient, the engine torque and the translation in the transmission 3 and the axle drive train 9 , which would occur with the next or precalculated gear. If it turns out that the driving force in this next gear is greater than the force resulting from the slope, then the shift is initiated and executed in this new precalculated gear. The speed drop occurring at the drive motor 1 due to the switching time due to the load interruption by opening the clutch 4 is taken into account in the calculation.

When driving in the partial load range of the drive motor 1 , the correct gear is selected on the basis of the detected acceleration values. If the pre-calculated acceleration of the vehicle falls below a predetermined limit value, the next higher or lower gear is selected which has the lowest fuel consumption. Shifting into this gear is subject to the following conditions, namely:

• - Specified limit speeds are not exceeded or un walked,
• - The specific fuel consumption is in the selected Gear smaller than in the current gear, and
• - After switching, the engine power can be the same be continued.

If the vehicle is to be operated at full engine load, the gear selection is based on acceleration, and a new gear is engaged as soon as one of the specified engine speed limits is exceeded or undershot. Different loading conditions are taken into account by the electronics 13, 101 and 131, respectively. In this case, too, the shift is omitted or no shift command is issued if the electronics 13 or 101 or 131 detect that the current speed cannot be maintained after the previously calculated gear has been engaged.

When the accelerator pedal 20 is actuated by kick-down (= signal e ), essentially the same operating strategy is followed as when driving at full engine load. A shift into a lower gear is initiated when, within the permissible speed range, a point with a higher engine output can be reached with the delivery quantity adjusting element 5 of the injection pump 2 deflected to the maximum.

Case 3: The vehicle drives over a hill, the driver sees a very slight slope:

In this case, the driver wants to slowly adjust the engine torque to the changed gradient and will therefore slowly take the accelerator pedal back to the zero position. In this driving situation, no gearshift should take place, rather the further course of the journey should be awaited. The electronics 13 or 101 or 131 recognizes this and will therefore initially suppress a shift into another gear.

Case 4: The driver sees himself some distance from the viewer keep forced:

In this case, the driver will very quickly return the accelerator pedal 20 to zero. A higher speed level should be permitted in the drive motor 1 and the braking action should accelerate the braking process. The electronics 13 or 101 or 131 recognizes this driver request due to the nega tiv accelerator pedal movement dynamics and triggers a return of the delivery rate 5 of the injection pump 2 , which has the consequence that then a negative torque is effective on the drive motor 1 . In addition, commands for shifting into lower gears are issued to the actuator 6 of the clutch 4 and the switching device 7 of the transmission 3 .

To define this stopping request from the electronics 13 or 101 or 131 but also information about the actuation of the engine brake member 28 (= signal g ) and the brake pedal 23 (= signal f ) are used. Based on these criteria, the following operating states are defined in overrun mode of the vehicle or drive motor, namely

• a) deceleration - recognized by actuation of brake pedal 23 ,
• b) Rolling - recognized from non-actuation of engine brake gan 28 and brake pedal 23 ,
• c) Throttles - recognized from actuation of the engine brake member 28 .

In each of these three signaling states, the electronics 13, 101 and 131, depending on the engine speed and the currently calculated deceleration, trigger the engagement of a correspondingly lower gear. With this downshift, several, for example up to four, gears can be skipped. Upper and lower engine speed limits are defined for each of these three message states. A shift into the pre-calculated gear is not triggered, however, if the drive motor 1 would assume an excessively high speed in the new smaller gear.

Case 5: The driver sees the end of a slope in front of him route:

The driver wants to take advantage of the remaining gradient to quickly bring the vehicle back up to the permissible maximum speed. This operating request is signaled by the driver by lightly accelerating with the accelerator pedal of electronics 13 or 101 or 131 . The latter converts this into commands that shift into higher gears and continue driving at the lowest possible engine speed.

Case 6: The driver sees himself at the end of a slope stretch an incline that starts again immediately:

In this case, the driver wants to drive up the slope with the highest possible engine torque and with the highest possible engine speed. This operating request is signaled by the driver at the end of the downhill area by quickly accelerating with the accelerator pedal 20 of the electronics 13 or 101 or 131 . In this case, the latter issues commands to the delivery quantity-adjusting member 5 of the injection pump 2 , the actuating member 6 of the clutch 4 and the switching device 7 of the gear 3 , with which a targeted shift into such a gear is effected which, in addition to the desired high speed level of the drive motor 1 - without turning it over - also allows a certain further acceleration of the vehicle.

Below are a few general notes.

The implementation of a Fahrwei se adapted to the driving situation is particularly important when driving on steep inclines and steep gradients, because through the load-interrupting circuit of the transmission 3 , i.e. with the clutch 4 open, during the shifting time on the axle drive train 9, no drive torque is available. Without targeted influence, gear changes in small gears would lead to considerable relative loss of speed (ascent) or increase in speed (descent). By knowing the exact size of the value of the slope or the slope, which the electronics 13 or 101 or 131 determines by calculation, several targeted influences are possible to minimize the effects of such load interruptions. Various explanations are given below, with the following note in advance: All of the following statements regarding uphill and speed losses during gear changes apply - if appropriate - analogously to downhill (valley runs) and speed increases during gear changes.

By calculating the loss of speed during the duration of a shift (when driving uphill), the gear 13, 101 or 131 is shifted into the required lower gear as early as possible. As a result, a drop in engine speeds that are too low is prevented as planned in the new gear, which under certain circumstances could lead to the gearshifting back into the old gear. In advance, the electronics 13 or 101 or 131 check by calculation whether a speed gain is possible at all through the circuit to be performed, or whether the speed gain that can be achieved by the circuit to be performed would be consumed again by a loss of speed.

The highest gear in which the speed can still be maintained when driving uphill results from the calculated size of the slope. As a result, after entering the incline while driving down the incline, it is specifically shifted down into this calculated gear. In addition, the electronics 13 or 101 or 131 calculate the possible acceleration with the latter before executing a shift into a new gear. This minimizes shifts in gears on gradients that do not allow vehicle acceleration.

Claims (17)

1. Electronic operating control system for a motor vehicle drive train, which has a drive motor ( 1 ), an automatically switchable, load-interrupting clutch ( 4 ) and an automatically switchable transmission ( 3 ) with an axle drive train ( 9 ) connected on the output side, with at least one electronics , which comprises a microprocessor, input and output periphery as well as program and data memory and, on the basis of signaled measured or operating values, enables the calculation of setpoints by program, which in corresponding commands are sent to the delivery quantity adjusting element ( 5 ) of the injection pump ( 2 ), the actuating member ( 6 ) of the clutch ( 4 ) and the switching device ( 17 ) of the transmission ( 3 ) are implemented, since characterized in that the electronics ( 13 , 101 , 131 ) is capable, according to its concept,

• a) on the basis of the measurement or operating data supplied ( a to r )
• - the acceleration of the vehicle,
• - the torque delivered by the drive motor ( 1 ) in traction or in overrun,
• - the forces acting on the vehicle from outside and in the direction of travel,
• - the mass of the vehicle,
• - the size of the ascent / descent and
• - To calculate the movement speed of the actuation of the accelerator pedal ( 20 ), also
• b) on the basis of such calculated values to recognize the topography and the condition of the terrain currently being used, and also
• c) on the basis of the calculated values and taking into account any actuation of the brake pedal ( 23 ) and engine brake element ( 28 ), interpret the driver's wishes for a specific future driving style from the size and dynamics of the anticipatory actuation of the accelerator pedal ( 20 ) and to implement commands adapted to the driving situation by which
• - The drive motor ( 1 ) to provide a certain torque be in a certain speed range,
• - The gear ( 3 ) for inserting a specific Gan, and
• - The clutch ( 4 ) for targeted opening and closing for the purpose of executing the initiated gear shift.

2. Operating control system according to claim 1, characterized in that the electronics ( 13 , 101 , 131 ) compute the current acceleration of the vehicle by deriving the measured output speed of the transmission ( 3 ) or the speed, which is directly proportional to the time becomes. 3. Operating control system according to claim 1, characterized in that the electronics ( 13 , 101 , 131 ) on the crankshaft of the drive motor ( 1 ) in train operation ne or in overrun torque absorbed from the fed into the drive motor ( 1 ) Fuel quantity - represented by a signal that detects the actual position of the conveying gene adjusting element ( 5 ) of the injection pump ( 2 ) - and the speed of the drive motor ( 1 ) in conjunction with a map of the data stored in a data memory ( 13 B , 101 B , 131 B ) Drive motor ( 1 ) is calculated. 4. Operating control system according to the preceding claims, characterized in that from the electronics ( 13 , 101 , 131 ) the opposing forces acting on the vehicle while driving from the outside against the direction of travel, such as against the wind, inclines and the like, from the precalculated values of Engine torque and acceleration taking into account the mass of the vehicle and the gear ratios in the transmission ( 3 ) and final drive train ( 9 ) are calculated. 5. Operating control system according to claims 1-3, characterized in that the electronics ( 13 , 101 , 131 ) the accelerating forces acting on the vehicle from the outside in the direction of travel, such as downward gradient, tailwind and the like, from the pre-calculated values of the engine torque and the acceleration and the braking torques applied by actuating the engine brake ( 19 , 88 ) and service brake ( 23 ), taking into account the vehicle mass and the gear ratios in the transmission ( 3 ) and axle drive train ( 9 ). 6. Operating control system according to one of the preceding claims, characterized in that the electronics of the electronics ( 13 , 101 , 131 ) calculate the mass of the vehicle in such a way that an average is formed from several mass calculations, each of which An on operation after the previous stop under the assumption "start in level" on the basis of the given engine torque and acceleration taking into account the gear ratios in the transmission ( 3 ) and axle drive train ( 9 ) is carried out and saved. 7. Operating control system according to claim 6, characterized in that to accelerate the average calculation of the mass se of the vehicle or to reduce the number of start-up processes used, the electronics ( 13 , 101 , 131 ) a "start value" of the mass can be entered, which can be determined by weighing the vehicle or from the empty weight of the vehicle with addition of the Ge weight of the load or payload detected by sensors and is included in the mass average calculation. 8. Operating control system according to one of claims 1 to 6, characterized in that of the electronics ( 13 , 101 , 131 ) the value of an uphill or downhill gradient, as is given immediately before the vehicle stops, from the values of the tractive force , the acceleration and the mass are calculated and saved and used to select an optimal starting gear. 9. Operating control system according to one of the preceding claims, characterized in that the speed of actuation of the accelerator pedal ( 20 ) by the electronics ( 13 , 101 , 131 ) by deriving the pedal movement between two signaled th rest positions according to the time it is averaged. 10. Operating control system according to one of the preceding claims, characterized in that of the electronics ( 13 , 101 , 131 ) after a previous stop of the vehicle the driver's wish for

• a) starting with normal acceleration by relatively fast and wide actuation of the accelerator pedal ( 20 ), and
• b) Starting for maneuvering or moving up or crawling gear by relatively slow actuation of the accelerator pedal ( 20 )

interpreted and in case a) by issuing a command for inserting the be before stopping for such starting calculated gear, in case b), however, in the issue of a Be failed to engage a necessary smaller gear is set. 11. Operating control system according to claim 10, characterized in that from the electronics ( 13 , 101 , 131 ) the off rose from the maneuvering or creeper mode of the vehicle is then initiated by issuing a command for engaging a higher gear when the current gear is greater than or equal to the starting gear calculated from the external force for normal starting. 12. Operating control system according to one of the preceding claims, characterized in that when the vehicle is in motion after starting, the electronics ( 13 , 101 , 131 ) basically distinguish between "choice of gear" and "execution of the circuit" is, the choice of gear based on the acceleration of the vehicle and thereby, if possible, gears can be skipped, whereas the execution of the circuit is tied to exceeding or falling below limit speeds, and wherein said acceleration values and limit speeds preprogrammed for all possible operating states in the electronics ( 13 , 101 , 131 ). 13. Operating control system according to claim 12, characterized in that the limit speeds depending on certain targets be variably stored in the electronics ( 13 , 101 , 131 ) programmed. 14. Operating control system according to claim 12, characterized in that the electronics ( 13 , 101 , 131 ) a be exceeded the limit speed with the gear engaged at full load of the drive motor ( 1 ) is permitted for the case when the vehicle in predicted next gear could no longer be accelerated. 15. The operating control system according to claim 12, characterized in that the electronics ( 13 , 101 , 131 ) issue a command for switching to the precalculated gear in the case when it detects that the speed after engaging the precalculated gear could be held. 16. Operating control system according to one of the preceding claims, characterized in that a number of different switching and engine operating strategies are preprogrammed in the electronics ( 13 , 101 , 131 ) for driving on terrain or road sections with certain topographical conditions are, each of which can be called up by linking the ratios of the topography traveled before with the driver-specific actuation of the accelerator pedal ( 20 ).