US3824392A - Detector to indicate burning or glowing particles - Google Patents

Detector to indicate burning or glowing particles Download PDF

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US3824392A
US3824392A US00353313A US35331373A US3824392A US 3824392 A US3824392 A US 3824392A US 00353313 A US00353313 A US 00353313A US 35331373 A US35331373 A US 35331373A US 3824392 A US3824392 A US 3824392A
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detector
light
particles
openings
conduit
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US00353313A
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K Tibbling
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PAK CONST AB
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PAK CONST AB
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    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B17/00—Fire alarms; Alarms responsive to explosion
    • G08B17/12—Actuation by presence of radiation or particles, e.g. of infrared radiation or of ions
    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62C—FIRE-FIGHTING
    • A62C35/00—Permanently-installed equipment
    • A62C35/58—Pipe-line systems
    • A62C35/60—Pipe-line systems wet, i.e. containing extinguishing material even when not in use
    • A62C35/605—Pipe-line systems wet, i.e. containing extinguishing material even when not in use operating and sounding alarm automatically
    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62C—FIRE-FIGHTING
    • A62C3/00—Fire prevention, containment or extinguishing specially adapted for particular objects or places
    • A62C3/04—Fire prevention, containment or extinguishing specially adapted for particular objects or places for dust or loosely-baled or loosely-piled materials, e.g. in silos, in chimneys

Definitions

  • Said detector includes a transducer suitable dis- 1 posed within the system, as on the tube wall of a trans- 56] References Cited port conduit. Said transducer gives signals in the form of a pulse train when such a particle passes through UNITED STATES PATENTS the visual field thereof. 2,016,036 10/1935 Gerald 250/237 2,198,725 4/1940 Smith 250/237 5 Claims, 4 Drawing Figures PATENTUJJUU 5 I974 V SHEET 1 [IF 2 TRANSDUCER ALARM UNIT C OUN TE R UNIT PULSE SHAPER FILTER UNIT I! AMPLIFIER 34/ PATENTEU JUU 51914 SHEET 2 OF 2 Fig.4 32
  • This invention refers to a detector to indicate hot, namely burning or glowing, particles in connection with the transport of a mass of particles.
  • inflammable particles as cellulose fibers
  • said particles can be so heated that they will form sparks or fire flakes within a risk zone or will be transported through such a zone by the carrier gas. If such glowing particles comprise sufficient quantities of energy they will initiate fire or explosion, causing serious damages with associated shut-downs.
  • the intention of the invention is undoubtedly to detect such glowing particles even if the speed thereof is high and to produce remedies within the shortest possible time, as milliseconds, to isolate said risk area and/or to supply firefighting or choking means prior to the initiation of said fire or explosion.
  • a transducer having at least two mutually separated sensing zones within the visual field of the particles, said zones in different positions of the hot particle and during the movement thereof and thus at successive moments supplying the radiation of heat of said particles to lightsensitive elements co-operating with each zone, so that signals sent from said zones form a train of pulses, which via an amplifier is then used to eliminate said particles.
  • opening of shutters for the day-light or the like opening of shutters for the day-light or the like.
  • FIG. 1 shows an embodiment of a detector having a DESCRIPTION OF THE INVENTION
  • reference number 10 discloses a'conduit through which a material in the form of particles, such as cellulose fibers, is transported by a gas medium, such as a mixture of air and combustion gases.
  • a transducer generally designed by 12, shaped in accordance to one of FIGS. 2-4.
  • a plate 14 is arranged on a housing 16 forming a number of cells 18, in this case six cells, mutually separated by partitions 20 and at the top covered by a roof 22 formed as a raster.
  • Said roof 22 includes mutually parallel and straight grooves or openings 24, one for each cell 18.
  • the roof is covered by a light or heat permeable layer 25 eliminating the penetration of strange particles into said cells 18.
  • Said grooves 24 extend perpendicular to the length of said conduit 10.
  • the separated cells 18 are shielded from similar to the grooves, there is a light-sensitive element 26, such as a photocell, which within the sensing zone or within a small space angle v limited by planes 28, 30, can catch heat and light radiation, respectively, supplied from the inside of said conduit.
  • a light-sensitive element 26 such as a photocell
  • the zones are separated from each other, and thus in case the glowing particle 32 passes through said conduit according to the drawn line 33 it will be within the visual field of the light sensitive element of the first sensing zone from position 32 to position 32. Then the effect of the particle on transducer 12 will be elimin'ated until said particle reaches the limit line 28 of the next'sensing zone where thenext light-sensitive element 26 receives heat radiation while said particle passes through this sensing zone to position 32 and so on. Thus, said glowing particle 32 will successively and for separate moments give its heat radiation to the successively arranged light sensitive elements 26.
  • the elements 26 are connected to one or more amplifiers 34 in a control equipment 36.
  • the signals supplied from the separate light-sensitive elements as a train of pulses then pass a filter unit 38 so formed that it-will only accept pulses, the slop of which (the front of the pulse) exceeds a set value contributing to make the detector insensitive to irrelevant disturbances.
  • the radiation from the glowing particles lies within the infrared area.
  • said transducer can be made insensible to normal day-light and to light for example from fluorescent lamps.
  • said filter unit ensures that irrelevant disturbances cannot start an alarm.
  • said detector is in several respects designed to prevent false triggering.
  • said detector responds to glowing particles also when the speed of flow within the visual field, as in conduit 10, is very high and thus the control equipment 36 will have time to quickly interrupt the process prior to the initiation of a fire or an explosion within the system.
  • FIG. 3 discloses a transducer having three lightsensitive elements 46 arranged in a chamber 48 the roof 22 of which functions as a raster.
  • Said roof 22 has the shape of a semisphere and includes grooves 50 extending in parallel and cutting into said semi-sphere to the level of the light-sensitive elements 26. By utilizing the grooves situated at the sides. A particle 32 passing centrally of the conduit will pass the grooves of the will pass to the control equipment 36 according to F IG.
  • saidftransducer 12 by means of a. partition 52 is divided and applied in two sensing zones separated from each other and each extending through a relatively large space angle v..Each zone includes a light-sensitive element 54.
  • the transducer is closed by a dome-shaped transparent covering 56. In this case the transducer is acted upon twice during the passage of the glowing particle 32 past the raster with an interruption over a distance determined by the separation 52.
  • a field within which the invention can be advantageously utilized is the drying of cellulose fibers produced by one or more grinding processes.
  • the damp fibers are then by the gas flow and by suitable blowers brought to a cyclone where the dried fibers are separated from the gas and the large part of the water contents.
  • the inventive detector is then arranged in the conduit between the drier and the cyclone to prevent fiber particles heated to glowing in said drier passing to the cyclone or to dust filters applied after the same, respectively.
  • said detector will practically immediately interrupt the drying process or supply fire eliminating means, respectively, into the system.
  • What I claim is: 1. In a detector of the type which is adapted to be mounted in a tubular conduit through which air-borne glowing particles may pass, and having a housing, at least two light-sensitive elements mounted in said housing, I
  • said covering member is semi-spherical in shape.
  • a detector as claimed in claim 1 wherein said covering member has a plurality of openings therethrough which are so spaced from one another that when the detector is mounted in a tubular conduit they will be spaced longitudinally of the conduit, said light-sensitive elements are in registry with said openings and said openings are arcuate so that each of said zones covers the total cross section of said conduit.
  • a detector as claimed in claim 2 having a single transparent cover disposed over said covering member.
  • openings are parallel and define the sensing zones.

Abstract

A detector to be utilized in processes where inflammable material is transported in conduits at a high speed. Then the detector will indicate glowing particles, as sparks and fire flakes, which may appear within a risk zone or are rapidly being transported through such a zone. Said detector includes a transducer suitable disposed within the system, as on the tube wall of a transport conduit. Said transducer gives signals in the form of a pulse train when such a particle passes through the visual field thereof.

Description

United States Patent 1191 [11] 3,824,392 Tibbling 5] July 16, 1974 [54] DETECTOR TO INDICATE BURNING OR 2,653,309 9/1953 Hauz 250/209 x GLOWING PARTICLES 2,774,961 12/1956 Orlando 340/258 B 2,931.913 4/1960 Lon Jr 250/209 Inventor: Kurt Eskil Tibbling, 591ml, Sweden 3,036,219 5/1962 Tho ipson... 340/258 B 3,399,307 8 1968 L 250 209 X [73] Ass1gnee: Pak Construction AB, Hudd nge, 3,480,775 I 3; n
swede 3.727.057 4 1973 Higby 250/209 [22] Filed: Apr. 23, 1973 Primary Examiner-James W. Lawrence [21] Appl' 3533l3 Assistant ExaminerT. N. Grigsby [30] A FgleilggnlzAp silicaition Priority Data 5380 72 [57] ABSTRACT pr. we en l A detector to be utilized in processes where inflamma- 52 U S CL": H 250/221 250/223 250/237 ble material is transported in COl'ldllltS at 8. high speed. -SAD/258 Then the detector will indicate glowing particles, as [511 Int. Cl. G08b 17/12 Sparks and fire flakes, hich may appear. within a risk [58] Field of Search 250/209 222 221 237 me or are rapidly being transported through S 9 E 5 zone. Said detector includes a transducer suitable dis- 1 posed within the system, as on the tube wall of a trans- 56] References Cited port conduit. Said transducer gives signals in the form of a pulse train when such a particle passes through UNITED STATES PATENTS the visual field thereof. 2,016,036 10/1935 Gerald 250/237 2,198,725 4/1940 Smith 250/237 5 Claims, 4 Drawing Figures PATENTUJJUU 5 I974 V SHEET 1 [IF 2 TRANSDUCER ALARM UNIT C OUN TE R UNIT PULSE SHAPER FILTER UNIT I! AMPLIFIER 34/ PATENTEU JUU 51914 SHEET 2 OF 2 Fig.4 32
1 DETECTOR TO INDICATE BURNING OR GLOWING PARTICLES SUMMARY-OF THE INVENTION This invention refers to a detector to indicate hot, namely burning or glowing, particles in connection with the transport of a mass of particles. As an example of a field within which the invention is applicable we can mention the pneumatic transport of inflammable particles, as cellulose fibers, in conduits in connection with the handling or the drying of the material. In that connection said particles can be so heated that they will form sparks or fire flakes within a risk zone or will be transported through such a zone by the carrier gas. If such glowing particles comprise sufficient quantities of energy they will initiate fire or explosion, causing serious damages with associated shut-downs. The intention of the invention is undoubtedly to detect such glowing particles even if the speed thereof is high and to produce remedies within the shortest possible time, as milliseconds, to isolate said risk area and/or to supply firefighting or choking means prior to the initiation of said fire or explosion. This is essentially obtained by a transducer, having at least two mutually separated sensing zones within the visual field of the particles, said zones in different positions of the hot particle and during the movement thereof and thus at successive moments supplying the radiation of heat of said particles to lightsensitive elements co-operating with each zone, so that signals sent from said zones form a train of pulses, which via an amplifier is then used to eliminate said particles. By using at least two zones effected by the glowing particle within a very short time interval the activation of an alarm is eliminated in connection with non-dangerous light or heat changes within the visual field, for example by the switching on of lamps, the
, opening of shutters for the day-light or the like.
DESCRIPTION OF THE DRAWINGS The invention will be described below more in detail with reference to the accompanying drawings, which as an example disclose an embodiment thereof and in connection therewith also other features of the invention will be set forth.
FIG. 1 shows an embodiment of a detector having a DESCRIPTION OF THE INVENTION In FIG. 1 reference number 10 discloses a'conduit through which a material in the form of particles, such as cellulose fibers, is transported by a gas medium, such as a mixture of air and combustion gases. On said conduit there is a transducer, generally designed by 12, shaped in accordance to one of FIGS. 2-4. In the embodiment according to FIG. 2 a plate 14 is arranged on a housing 16 forming a number of cells 18, in this case six cells, mutually separated by partitions 20 and at the top covered by a roof 22 formed as a raster. Said roof 22 includes mutually parallel and straight grooves or openings 24, one for each cell 18. The roof is covered by a light or heat permeable layer 25 eliminating the penetration of strange particles into said cells 18. Said grooves 24 extend perpendicular to the length of said conduit 10. The separated cells 18 are shielded from similar to the grooves, there is a light-sensitive element 26, such as a photocell, which within the sensing zone or within a small space angle v limited by planes 28, 30, can catch heat and light radiation, respectively, supplied from the inside of said conduit. Thus, each sensing zone perpendicularly to the plane of the drawing forms a. groove limitedby planes 28, 30. According to FIG; 2 the zones are separated from each other, and thus in case the glowing particle 32 passes through said conduit according to the drawn line 33 it will be within the visual field of the light sensitive element of the first sensing zone from position 32 to position 32. Then the effect of the particle on transducer 12 will be elimin'ated until said particle reaches the limit line 28 of the next'sensing zone where thenext light-sensitive element 26 receives heat radiation while said particle passes through this sensing zone to position 32 and so on. Thus, said glowing particle 32 will successively and for separate moments give its heat radiation to the successively arranged light sensitive elements 26.
The elements 26 are connected to one or more amplifiers 34 in a control equipment 36. The signals supplied from the separate light-sensitive elements as a train of pulses then pass a filter unit 38 so formed that it-will only accept pulses, the slop of which (the front of the pulse) exceeds a set value contributing to make the detector insensitive to irrelevant disturbances.
Then said train of pulses passes a pulse shaper 40, a
counter unit 42 and an alarm unit 44, from which alarm signals are sent. In order to start an alarm in the embodiment according to FIG. 2, six successive lightsensitive elements 26 have to be subjected to the radiation of the glowing particle. Then the intention is to eliminate incoming light effects which are not dangerous but which in spite of this affect the light-sensitive elements and are not filtered out by the filter unit 38. The number of accepted pulses is counted by the counter unit 42 which automatically resets said detector to zero in case the set number of pulses has not entered within the normal time, whereby a false alarm is prevented.
Normally the radiation from the glowing particles lies within the infrared area. By the selection of the lightsensitive element said transducer can be made insensible to normal day-light and to light for example from fluorescent lamps. By the fact that only incoming pulses having a high slope are accepted said filter unit ensures that irrelevant disturbances cannot start an alarm. Thus, said detector is in several respects designed to prevent false triggering. On the other hand said detector responds to glowing particles also when the speed of flow within the visual field, as in conduit 10, is very high and thus the control equipment 36 will have time to quickly interrupt the process prior to the initiation of a fire or an explosion within the system.
FIG. 3 discloses a transducer having three lightsensitive elements 46 arranged in a chamber 48 the roof 22 of which functions as a raster. Said roof 22 has the shape of a semisphere and includes grooves 50 extending in parallel and cutting into said semi-sphere to the level of the light-sensitive elements 26. By utilizing the grooves situated at the sides. A particle 32 passing centrally of the conduit will pass the grooves of the will pass to the control equipment 36 according to F IG.
1 in the same way described above. The embodiment according to FIG. 3 is independent of the direction of transport of the particle.
In the embodiment according to FIG. 4 saidftransducer 12 by means of a. partition 52 is divided and applied in two sensing zones separated from each other and each extending through a relatively large space angle v..Each zone includes a light-sensitive element 54. The transducer is closed by a dome-shaped transparent covering 56. In this case the transducer is acted upon twice during the passage of the glowing particle 32 past the raster with an interruption over a distance determined by the separation 52.
A field within which the invention can be advantageously utilized is the drying of cellulose fibers produced by one or more grinding processes. The damp fibers are then by the gas flow and by suitable blowers brought to a cyclone where the dried fibers are separated from the gas and the large part of the water contents. The inventive detector is then arranged in the conduit between the drier and the cyclone to prevent fiber particles heated to glowing in said drier passing to the cyclone or to dust filters applied after the same, respectively. Hereby the otherwise great risk of fire and explosion will be eliminated by the fact that said detector will practically immediately interrupt the drying process or supply fire eliminating means, respectively, into the system.
Of course this invention is not limited to the disclosed embodiments but can be widely modified within the scope of the invention. By selecting different. types of light-sensitive elements or by utilizing different types of filters the transducer can be made sensitive to radiation of any wanted frequency.
What I claim is: 1. In a detector of the type which is adapted to be mounted in a tubular conduit through which air-borne glowing particles may pass, and having a housing, at least two light-sensitive elements mounted in said housing, I
means within said housing separating said lightsensitive elements from one another to form separate sensing zones in said housing,
a light-permeable covering member extending over said elements, and
means including an amplifier connected to said detector to form a chain of pulses from said lightsensitive elements for use in eliminating said particles, v
the improvement wherein said covering member is semi-spherical in shape.
2. A detector as claimed in claim 1, wherein said covering member has a plurality of openings therethrough which are so spaced from one another that when the detector is mounted in a tubular conduit they will be spaced longitudinally of the conduit, said light-sensitive elements are in registry with said openings and said openings are arcuate so that each of said zones covers the total cross section of said conduit.
3. A detector as claimed in claim 2 having a single transparent cover disposed over said covering member.
openings are parallel and define the sensing zones.

Claims (5)

1. In a detector of the type which is adapted to be mounted in a tubular conduit through which air-borne glowing particles may pass, and having a housing, at least two light-sensitive elements mounted in said housing, means within said housing separating said light-sensitive elements from one another to form separate sensing zones in said housing, a light-permeable covering member extending over said elements, and means including an amplifier connected to said detector to form a chain of pulses from said light-sensitive elements for use in eliminating said particles, the improvement wherein said covering member is semi-spherical in shape.
2. A detector as claimed in claim 1, wherein said covering member has a plurality of openings therethrough which are so spaced from one another that when the detector is mounted in a tubular conduit they will be spaced longitudinally of the conduit, said light-sensitive elements are in registry with said openings and said openings are arcuate so that each of said zones covers the total cross section of said conduit.
3. A detector as claimed in claim 2 having a single transparent cover disposed over said covering member.
4. A detector as claimed in claim 2, wherein said openings are of different length.
5. A detector as claimed in claim 2, wherein said openings are parallel and define the sensing zones.
US00353313A 1972-04-24 1973-04-23 Detector to indicate burning or glowing particles Expired - Lifetime US3824392A (en)

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SE05380/72A SE364588B (en) 1972-04-24 1972-04-24

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DE (1) DE2319033C3 (en)
DK (1) DK142735B (en)
FI (1) FI60615C (en)
FR (1) FR2182486A5 (en)
GB (1) GB1397158A (en)
NO (1) NO131525C (en)
SE (1) SE364588B (en)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3896311A (en) * 1974-01-02 1975-07-22 Minnesota Mining & Mfg Pyroelectric motion and temperature sensitive infrared detector with conductive fingers
US3958118A (en) * 1975-02-03 1976-05-18 Security Organization Supreme-Sos-Inc. Intrusion detection devices employing multiple scan zones
US4520343A (en) * 1980-12-16 1985-05-28 Hiroshi Koh Lift control system
US4554459A (en) * 1981-01-27 1985-11-19 Fujitec Co., Ltd. Monitoring system for a predetermined field of view
US5196689A (en) * 1990-10-16 1993-03-23 Pioneer Electronic Corporation Device for detecting an object including a light-sensitive detecting array
US5548276A (en) * 1993-11-30 1996-08-20 Alan E. Thomas Localized automatic fire extinguishing apparatus
US5749420A (en) * 1993-10-08 1998-05-12 Firefly Ab Device for particles detection in a pipeline
EP1413998A2 (en) * 2002-10-25 2004-04-28 Forschungsgesellschaft für angewandte Systemsicherheit und Arbeitsmedizin Device for the recognition of smouldering fire hotspots
US6732810B1 (en) * 1998-12-29 2004-05-11 Firefly Ab Detector system for detecting glowing particles
USRE39081E1 (en) * 1993-11-30 2006-05-02 Alan E. Thomas Localized automatic fire extinguishing apparatus
US20100265510A1 (en) * 2009-04-21 2010-10-21 Minimax Gmbh & Co. Kg Device for recognizing and reporting fire phenomena with combustible materials
EP2881719A1 (en) * 2013-12-03 2015-06-10 Atexon Oy Detecting of sparks
US9162095B2 (en) 2011-03-09 2015-10-20 Alan E. Thomas Temperature-based fire detection
SE1850206A1 (en) * 2018-02-23 2019-08-24 Firefly Ab Determination of risk level for particles
SE1850207A1 (en) * 2018-02-23 2019-08-24 Firefly Ab Monitoring of particle temperature trends

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2852971C2 (en) * 1978-12-07 1985-02-14 Preussag Ag Feuerschutz, 2060 Bad Oldesloe Fire alarm
GB9215757D0 (en) * 1992-07-24 1992-09-09 Bridisco Ltd A pir sensor device

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US2198725A (en) * 1937-12-09 1940-04-30 Hammond V Hayes Alarm system
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US3036219A (en) * 1958-05-01 1962-05-22 Arthur V Thompson Passive radiation proximity detector
US3399307A (en) * 1965-05-20 1968-08-27 Bell & Howell Co Motion sensing exposure system for optical instruments
US3480775A (en) * 1964-08-17 1969-11-25 Gen Dynamics Corp Radiation sensitive omnidirectional motion detector system
US3727057A (en) * 1962-06-15 1973-04-10 Westinghouse Electric Corp Infrared detector device with a mosaic of oppositely-poled adjacent elements

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Publication number Priority date Publication date Assignee Title
US2016036A (en) * 1932-02-04 1935-10-01 Gerald Alan S Fits Photo-electric system
US2198725A (en) * 1937-12-09 1940-04-30 Hammond V Hayes Alarm system
US2653309A (en) * 1950-03-09 1953-09-22 Gen Electric Object detection
US2931913A (en) * 1953-01-02 1960-04-05 Jr Geary A Long Radiation receiver
US2774961A (en) * 1954-08-30 1956-12-18 Orlando Carl Moving object indicator
US3036219A (en) * 1958-05-01 1962-05-22 Arthur V Thompson Passive radiation proximity detector
US3727057A (en) * 1962-06-15 1973-04-10 Westinghouse Electric Corp Infrared detector device with a mosaic of oppositely-poled adjacent elements
US3480775A (en) * 1964-08-17 1969-11-25 Gen Dynamics Corp Radiation sensitive omnidirectional motion detector system
US3399307A (en) * 1965-05-20 1968-08-27 Bell & Howell Co Motion sensing exposure system for optical instruments

Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3896311A (en) * 1974-01-02 1975-07-22 Minnesota Mining & Mfg Pyroelectric motion and temperature sensitive infrared detector with conductive fingers
US3958118A (en) * 1975-02-03 1976-05-18 Security Organization Supreme-Sos-Inc. Intrusion detection devices employing multiple scan zones
US4520343A (en) * 1980-12-16 1985-05-28 Hiroshi Koh Lift control system
US4554459A (en) * 1981-01-27 1985-11-19 Fujitec Co., Ltd. Monitoring system for a predetermined field of view
US5196689A (en) * 1990-10-16 1993-03-23 Pioneer Electronic Corporation Device for detecting an object including a light-sensitive detecting array
US5749420A (en) * 1993-10-08 1998-05-12 Firefly Ab Device for particles detection in a pipeline
US5548276A (en) * 1993-11-30 1996-08-20 Alan E. Thomas Localized automatic fire extinguishing apparatus
USRE37493E1 (en) 1993-11-30 2002-01-01 Alan E. Thomas Localized automatic fire extinguishing apparatus
USRE39081E1 (en) * 1993-11-30 2006-05-02 Alan E. Thomas Localized automatic fire extinguishing apparatus
US6732810B1 (en) * 1998-12-29 2004-05-11 Firefly Ab Detector system for detecting glowing particles
EP1413998A2 (en) * 2002-10-25 2004-04-28 Forschungsgesellschaft für angewandte Systemsicherheit und Arbeitsmedizin Device for the recognition of smouldering fire hotspots
DE10249743A1 (en) * 2002-10-25 2004-05-06 Forschungsgesellschaft für angewandte Systemsicherheit und Arbeitsmedizin e.V. Device for detecting smoldering nests
EP1413998A3 (en) * 2002-10-25 2004-11-17 Forschungsgesellschaft für angewandte Systemsicherheit und Arbeitsmedizin Device for the recognition of smouldering fire hotspots
EP2244237A1 (en) 2009-04-21 2010-10-27 Minimax GmbH & Co. KG Device for recognising and reporting sparks of combustible materials
US20100265510A1 (en) * 2009-04-21 2010-10-21 Minimax Gmbh & Co. Kg Device for recognizing and reporting fire phenomena with combustible materials
US10864398B2 (en) 2011-03-09 2020-12-15 C. Douglass Thomas Temperature-based fire protection
US9162095B2 (en) 2011-03-09 2015-10-20 Alan E. Thomas Temperature-based fire detection
US10086224B2 (en) 2011-03-09 2018-10-02 Alan E. Thomas Temperature-based fire detection
US10376725B2 (en) 2011-03-09 2019-08-13 C. Douglass Thomas Temperature-based fire detection
EP2881719A1 (en) * 2013-12-03 2015-06-10 Atexon Oy Detecting of sparks
US9664622B2 (en) 2013-12-03 2017-05-30 Atexon Oy Spark sensing device with optical element
SE1850206A1 (en) * 2018-02-23 2019-08-24 Firefly Ab Determination of risk level for particles
WO2019162008A1 (en) 2018-02-23 2019-08-29 Firefly Ab Determination of risk level for particles
WO2019162011A1 (en) 2018-02-23 2019-08-29 Firefly Ab Monitoring of particle temperature trends
CN111771107A (en) * 2018-02-23 2020-10-13 荧火虫有限公司 Determining a risk level of a particle
SE1850207A1 (en) * 2018-02-23 2019-08-24 Firefly Ab Monitoring of particle temperature trends
CN111771107B (en) * 2018-02-23 2023-09-12 荧火虫有限公司 Determining a risk level of particles
US11927486B2 (en) 2018-02-23 2024-03-12 Firefly Ab Monitoring of particle temperature trends

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Publication number Publication date
FI60615B (en) 1981-10-30
GB1397158A (en) 1975-06-11
FI60615C (en) 1982-02-10
FR2182486A5 (en) 1973-12-07
NO131525B (en) 1975-03-03
DE2319033C3 (en) 1978-05-11
DK142735B (en) 1981-01-05
NO131525C (en) 1975-06-11
SE364588B (en) 1974-02-25
DE2319033A1 (en) 1973-11-15
DE2319033B2 (en) 1977-09-22
DK142735C (en) 1981-08-10

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