US3915134A - Exhaust gas recirculation system for internal combustion engines - Google Patents

Exhaust gas recirculation system for internal combustion engines Download PDF

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Publication number
US3915134A
US3915134A US447573A US44757374A US3915134A US 3915134 A US3915134 A US 3915134A US 447573 A US447573 A US 447573A US 44757374 A US44757374 A US 44757374A US 3915134 A US3915134 A US 3915134A
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United States
Prior art keywords
engine
exhaust gas
valve
load
signal
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US447573A
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English (en)
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Richard N Young
Larry O Gray
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Dana Inc
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Dana Inc
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Priority to US447573A priority Critical patent/US3915134A/en
Priority to CA219,041A priority patent/CA1015623A/en
Priority to DE19752508736 priority patent/DE2508736A1/de
Priority to IT20871/75A priority patent/IT1033379B/it
Priority to AU78752/75A priority patent/AU487245B2/en
Priority to FR7506699A priority patent/FR2263385B1/fr
Priority to ES435262A priority patent/ES435262A1/es
Priority to NL7502557A priority patent/NL7502557A/xx
Priority to GB8832/75A priority patent/GB1494687A/en
Priority to SE7502398A priority patent/SE408081B/xx
Priority to JP50026438A priority patent/JPS6011214B2/ja
Application granted granted Critical
Publication of US3915134A publication Critical patent/US3915134A/en
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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
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D41/0047—Controlling exhaust gas recirculation [EGR]
    • F02D41/0077—Control of the EGR valve or actuator, e.g. duty cycle, closed loop control of position
    • 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
    • F02B1/00—Engines characterised by fuel-air mixture compression
    • F02B1/02—Engines characterised by fuel-air mixture compression with positive ignition
    • F02B1/04—Engines characterised by fuel-air mixture compression with positive ignition with fuel-air mixture admission into cylinder
    • 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
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D41/0047—Controlling exhaust gas recirculation [EGR]
    • F02D41/005—Controlling exhaust gas recirculation [EGR] according to engine operating conditions
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/40—Engine management systems

Definitions

  • ABSTRACT Apparatus for electronically controlling exhaust gas recirculation in an internal combustion diesel engine to reduce nitrogen oxide emissions.
  • An exhaust gas recirculation control valve is driven by a feedback cir- 52 US. Cl. 123/119 A; 123/119 A Chit which Compares the valvfi Position with the 51 Im. cl. F02M 25/06 s lofld- A maximum amount of exhaust gas is recir- [58] Field of Search 123/119 A culated under a (How condition AS the load creases to 100%, the amount of recirculated exhaust [56] Ref Cited gas is decreased down to zero percent.
  • the amount of UNITED STATES PATENTS recirculated exhaust gas also may be affected by the engine speed to minimize smoke in the engine ex- 2,456,2l3 12/1948 Pele 123/119 A haust 3,636,934 l/l972 Nakajima et al....; 123/119 A 3,799,133 3/1974 Frank 123/119 A 10 Claims, 5 Drawing Figures /.5 f L v ENGINE /6 /Z /4 f I EXHAUST SENSORS I g I v VALVE Ay DR iv 2 l0 MOTOR uscrnomc 1 Z 0 CONTROLLE R VALVE POSITION SENS US. Patent Oct.28, 1975 sheet 1 on 3,915,134
  • the exhaust from internal combustion engines consists of various constituents including fully oxidized products of combustion such as carbon dioxide and'water plus undesirable pollutants such as partially oxidized, cracked and other hydrocarbons, carbon monoxide, oxides of nitrogen and traces of miscellaneous other pollutants.
  • the carbon dioxide and water emissions are unharmful.
  • the other exhaust emission constituents are considered highly undesirable.
  • the presence of nitrogen oxides in engine exhaust is determined by the combustion temperature.
  • An increase in combustion temperature causes an increase in the amount of nitrogen oxides present in the engine exhaust. It is therefore desirable to control the combustion temperature to limit the oxides of nitrogen present in the exhaust of an internal combustion engine.
  • One method suggested in the prior art for limiting or controlling the combustion temperature has been to recirculate a portion of the exhaust gas back to the engine air intake. Since the exhaust gas is low in oxygen, this will result in a richer combustion mixture which will burn at a lower temperature. The lower combustion temperature will, in turn, reduce the amounts of nitrogen oxides produced during combustion.
  • the operating conditions which result in the highest combustion temperatures depend upon the type of internal combustion engine.
  • the combustion temperature will be at a low point during idle.
  • the temperature will also be at a low point atwide open throttle since engines of this type will normally have a rich fuel mixture under this condition.
  • a maximum combustion temperature occurs during a no-load condition at idle. Therefore, it is desirable to have a maximum amount of exhaust gas recirculation during idle and to decrease this amount as the load increases to 100% of the rated load.
  • a third valve is provided for each cylinder for introducing exhaust gas directly into the cylinder.
  • a mechanical valve is provided in series between the engine exhaust and all of the valves which introduce the exhaust gas into the cylinders to control the amount of exhaust gas recirculated.
  • Various systems have also been adapted to spark-ignited internal combustion engines.
  • each of the prior art recirculation systems has incorporated a mechanical control operating from devices such as cams, centrifugal speed sensors, pneumatic vacuum or pressure sensors, and the like.
  • an electronic control for exhaust gas recirculation in internal combustion engines.
  • the control is particularly suitable for meeting the various requirements of a diesel engine to reduce nitrogen oxide emissions.
  • the control includes a sensor which measures the load on the engine.
  • the engine load signal is used as a primary control over the position of an exhaust gas recirculation valve.
  • a feedback circuit is provided for sensing the position of the exhaust gas recirculation valve.
  • the valve position is compared with the engine load for generating a signal which operates a valve drive motor.
  • the control circuit is also provided with means for maintaining the recirculation valve wide open or in a maximum recirculation condition whenever the load is at a minimum or the engine is idling.
  • the control may also be modified to further increase its efficiency in reducing nitrogen oxide and other emissions.
  • An engine speed sensor may be provided for modifying at higher engine speeds the rate at which the exhaust gas recirculation valve is closed under increasing load conditions.
  • the speed sensor may further be adapted to assure that the recirculation valve is closed when a predetennined maximum engine speed is exceeded and the load on the engine is simultaneously at a minimum, as when the engine is coasting at a high speed.
  • Such controls will have the advantage of not only minimizing the nitrogen oxide emissions, but also minimizing the amount of smoke produced by the engine which, although not considered highly harmful, is also undesirable.
  • a further object of the invention is to provide an improved exhaust gas recirculation system for diesel engines.
  • Still another object of the invention is to provide an improved exhaust gas recirculation control for diesel engines which operates at maximum efficiency under various conditions of load and engine speed for reducing nitrogen oxide emissions.
  • FIG. 1 is a'schematic block diagram of an internal combustion engine incorporating an exhaust gas recirculation system constructed in accordance with the present invention
  • FIG. 2 is a detailed schematic block diagram of an exhaust gas recirculation control constructed in accordance with a first embodiment of the invention
  • FIG. 3 isa graph showing typical signals generated for operating the drive motor for the exhaust gas recirculation valve
  • FIG. 4 is a chart showing typical operating characteristics for a second embodiment of a control for an exhaust gas recirculation system according to the present invention.
  • FIG. 5 is a detailed schematic block diagram of the second embodiment of 'an exhaust gas recirculation control according to the present invention.
  • FIG. l a block diagram is shown for an exhaust gas recirculation system embodying'the'principles of the present invention.
  • the system 10 is shown connected to'a conventional diesel engine 11 which, for example, may be of the type used in-trucks, construction machinery and the like.
  • the diesel engine 11 is provided with an :air intake 12 and an exhaust gas outlet 13.
  • the exhaust gas outlet 13 is connected through a valve 14 to an exhaust pipe 15 which leads to the atmosphere.
  • the ex haust pipe 15 may include a sound muffling system (not shown).
  • the valve 14 includes an adjustable flap 16 which diverts a controlled portion of the exhaust gas through a return pipe 17 to the air intake 12.
  • One or more sensors 18 are connected to the engine 11 for measuring at least the engine load and, in a preferred embodiment, also the engine speed.
  • the output of thesensors 18 is applied to an electronic controller 19 which drives a motor 20 for positioning the valve flap l6.
  • a feedback circuit is preferably provided for assuring a positive operation of the exhaust gas recirculation system 10.
  • the feedback circuit includes a valve position sensor '21 which applies a signal to the electronic controller 19 which corresponds to the position of the valve flap l6.
  • the electronic controller 19 is designed to compare the signal corresponding to the actual position of the valve flap 16 with a desired position as determined by the engine load conditions monitored by the sensors 18 and to use a resultant signal for driving the valve drive motor 20.
  • the electronic controller 19 drives the motor 20 to position the valve flap 16 for permitting a predetermined maximum amount of exhaust gas recirculation under a no-load condition and to linearly decrease the amount of exhaust gas recirculation by closing the valve flap 16 as the engine load increases until at 100% rated load substantially no exhaust gas is recirculated through the return pipe 17.
  • the electronic controller 19 is also provided with means for assuring that the valve flapl6 is at its maximum open position for recirculating a maximum amount of exhaust gas whenever either the engine load or the engine speed is less than a predetermined amount. This will assure that .the valve flap 16 will remain open during idle of or minimum load on the engme.
  • FIG. 2 a schematic block diagram is shown for the exhaust gas recirculation system 10 with details of connections: for an electronic controller 19 for perfomiing the above-described functions.
  • the load may be readily measured from the position of the rack which controls the amount of fuel injected into each cylinder.
  • the rack position may be measured by various conventional manners. For example, a linear voltage differential transformer may be connected to have a core move by the rack.
  • this arrangement has the disadvantage of placing a load on the rack which may affect the engine operation, particularlywhere the rack position is adjusted by a sensitive 'govemor.
  • the rack position is determined by a proximity detector or other device which need not be connected directly to the rack.
  • the load sensor 18 consists of a proximity probe 25 which senses the location of a cam surface 26 carried by the rack (not shown).
  • 'An oscillator 27 is connected to provide a relatively low frequency alternating current signal to an input of the proximity probe 25.
  • the alternating current signal may, for example, be on the order of 3 kI-Iz., although the frequency is not critical and will depend upon the probe design.
  • the proximity probe 25 will then have an output 28 of the same frequency as that of the oscillator 27 and of a magnitude which is inversely dependent upon the spacing from the cam 26.
  • the output 28 from the probe 25 is connected through a buffer amplifier 29 to a demodulator 30 which may, for example, consist of a half wave rectifier.
  • the demodulator 30 has an output 3l which is applied through a low pass filter 32 to one input of a compare circuit 33.
  • the low pass filter 32 should have a sufficiently low cut-off as to filter any engine vibrations present on the cam 26.
  • the low pass filter 32 is designed to only partially filter'the demodulator output 31, leaving a ripple on the signal applied to the compare circuit 33 which is of the same frequency as the output from the oscillator 27.
  • the output 31 from the demodulator 30 is also connected through a diode 34 and a variable resistor 35 to ground.
  • the variable resistor 35 may be used for adjusting the gain or load span over which the exhaust gas recirculation valve 14 is operated. I
  • the output from the oscillator 27 is also connected to the valve position sensor 21 which consists of a proximity probe 36.
  • a cam 37 is connected to be driven by the valve drive motor 20 along with the adjustable valve flap 16.
  • the proximity probe 36 senses the spacing to the cam 37 and generates an output 38 which is inversely proportional to such spacing.
  • the proximity probe output 38 will be of the same frequency as the output from the oscillator 27 and will increase in value as the cam 37 approaches the proximity probe the demodulator 40 for establishing a zero point for the system 10.
  • the output of the demodulator 40 is connected through a low pass filter 42 to a second input of the compare circuit 33 for comparison with the output from the low pass filter 32. In a typical diesel engine,- the peak engine vibration is on the order of between Hz.
  • the output of the compare circuit 33 is applied through an amplifier 43 to a bipolar power switch 44 which controls power to the valve drive motor 20.
  • the operation ofthe compare circuit 33 and the bipolar power switch 44 for operating the motor 20 may 'be more clearly understood by referring now to FIG. 3.
  • Graph A in FIG. 3 shows typical inputs appearing on the comparator 33.
  • the low pass filter 32 applies a signal 48 to the comparator 33 while the low pass filter 42 applies a signal of the type shown as 49a, 49b or 49c to the comparator 33.
  • the comparator 33 may consist of a Schmitt trigger which acts as a threshold detector and has one of two outputs, depending upon which of its two inputs is highest.
  • a signal of the type shown in FIG. 3B is applied to the bipolar power switch 44; If the ripple level of the load signal 48 is 50% above and 50% below the valve position signal as shown at 49b, then a signal of the type shown in FIG. 3C is applied to the bipolar power switch 44. If the majority of the ripple in the engine load signal 48 is above the valve position signal, as shown at 490, then a signal of the type shown in FIG. 3D is applied to the bipolar power switch 44.
  • the bipolar power switch 44 will apply a signal to the valve drive motor 20 similar to those shown in FIGS. 3B, C and D. These signals alternate between equal positive and negative voltages.
  • the signal on the motor 20 will be positive for a greater time than it is negative and the motor will be driven in the opposite direction.
  • the duty cycle of the power applied to the motor 20 will approach 5050 and the motor torque and speed will decrease.
  • valve 14 should be operated in a linear fashion with linear load changes. It is desirable to have maximum recirculation of exhaust gas at no-load and to have a minimum recirculation at 100% rated load with the amount of recirculation varying linearly be? tween these points.
  • the valve 14 may be of a linear type, it is less expensive to use a non-linear valve. Non-linearitiesin the, operation of the valve 14 may then be compensated for by providing an appropriately shapedsurface on the cam 37 which is rotated with the valve flap l6. 1 1
  • a second comparator 50 compares the output of the low;pass filter 32 with a fixed voltage obtained from a potentiometer 51.
  • the potentiometer 51 is used for establishing a trip point at which the recirculation valve 14 is driven toa fully open condition.
  • the output from the comparator 50 changes. This output is applied to the comparator 33 along with the valve position sig nal fromthe low pass filter 42.
  • the comparator 33 will then have a constant output regardless of its input from the low pass filter 32 and will cause the motor 20 to drive the valve 14 to itsfully open state.
  • the exhaust gas recirculation system 10 may be made even more efficient.
  • adiesel engine is typically operated in the range of 1,800 to 2,800 rpm. If the engine is used, for example, in a truck, the maximum normal op-. erating speed may be exceeded when the truck is coasting down a hill. During coasting, the driver will normally let up on the accelerator. Since the rack indicates a no-load condition, the exhaust gas recirculation valve 14 will normally be driven fully .open. Underthese conditions, the engine may emit smoke when the driver again hits the accelerator.
  • a control may be added to drive the exhaust gas recirculation valve 14 to a'fully closed position when the engine is under a noload condition and the engine speed exceeds a preselected maximum speed, such as 3,000 rpm.
  • a control may also be provided to drive the exhaust gas recirculation valve 14 to a fully open position at a preselected minimum engine speed, such as 1,200 rpm, regardless of the load on the engine.
  • Still another control may be provided to minimize smoke in the normal operating range, which, although being appreciably less harmful than nitrogen oxide emissions, is undesirable. It has been determined that less exhaust gas recirculation can be tolerated at lower engine speeds than at higher engine speeds to prevent the engine from smoking.
  • a control may also be added to shift the linear curve on which the exhaust gas recirculation valve 14 is operated in response to a predetermined engine speed. For example, smoking may be minimized if the exhaust gas recirculation valve 14 recirculates be tween 35% and 0% of the exhaust gas when the engine is operating between zero load and full load below 1,950 rpm and to recirculate between 50% and 0% of the exhaust gas when the engine is operatingbetween no-load and full load above 1,950 rpm.
  • This type of operation of the exhaust gas recirculation valve 14 is shown in the graph in FIG. 4'.
  • the apparatus 52 includes an oscillator 53 having an output applied through a' buffer amplifier 54 to the inputs of proximity probes 55 and 56.
  • the proximity probe 55 is mounted to measure the position of a cam or lobe 57 carried by the fuel rack (not shown) which controls the fuel injectors in a diesel engine.
  • the output of the proximity probe 55 is in the form of an alternating current signal having a level inversely proportional to the spacing to the cam 57 and the same frequency as the oscillator 53. This output is applied through an amplifier 58 to a demodulator 59.
  • the output of the demodulator 59 is filtered by means of a low pass filter 60 and applied to one input of a comparator 61.
  • the gain of the signal applied to the comparator 61 may be controlled by means of a diode 62 and a variable resistor 63 connected between the input of the low pass filter 60 and ground in a manner similar to that described above for FIG. 2.
  • the proximity probe 56 is connected to measure the spacing to a cam 64 which is driven by the valve drive motor 20 along with the flap 16 of the exhaust gas recirculation valve 14.
  • the alternating current output from the proximity probe 56 which is indicative of the position of the valve 14, is applied through an amplifier 65 to a demodulator 66.
  • a DC voltage is applied from a potentiometer 67 to the demodulator 66 for zeroing the apparatus 52.
  • the output from the demodulator 66 is applied through a low pass filter 68 to a second input of the comparator 61.
  • the output of the comparator 61 which alternates between two levels, is applied through an amplifier 69 and a bipolar switch 70 for driving the valve motor 20.
  • the operation of the circuitry described so far for FIG. is the same as that described above for the circuitry shown in FIG. 2. However, a number of additional controls are added for further reducing both smoke and nitrogen oxide emissions.
  • a lobed cam 75 is mounted to be driven by the engine.
  • a magnetic pickup 76 is positioned adjacent the lobed cam 75 for generating a pulse train having a frequency proportional to the engine speed.
  • the output of the magnetic pickup 76 is applied to a frequency-to-voltage converter 77 which generates a DC output 78 having a voltage level proportional to the engine speed.
  • the converter output 78 is applied to one input of a comparator 79.
  • a second input to the comparator 79 is a fixed voltage determined by a potentiometer 80.
  • the comparator 79 will have one of two outputs which depend upon whether or not the converter output 78 is above or below the voltage set by the potentiometer 80.
  • the potentiometer is adjusted such that the output from the comparator 79 will change levels at a relatively low engine speed, such as 1,200 rpm.
  • the output from the comparator 79 is applied along with the output from the low pass filter 60 to the comparator 61.
  • valve 14 is maintained in a fully closed position whenever the speed of the engine exceeds it normal operating range and simultaneously the fuel injection rack is at a minimum or low load setting.
  • This is accomplished by means of a pair of comparators 81 and 82 and an AND gate 83.
  • the output 78 from the converter 77 which is proportional to engine speed, is applied to one input of the comparator 81.
  • a potentiometer 84 applies a fixed voltage to the second input of the comparator 81 for determining the engine speed at which the output from the comparator 81 changes.
  • the potentiometer 84 will be adjusted such that the output from the comparator 81 changes levels when the engine speed slightly exceeds its normal operating range, such as 3,000 rpm.
  • the output from the comparator 81 is applied to one input of the AND gate 83.
  • the comparator 82 has one input which is connected to the output of the low pass filter 60, which output is indicative of the position of the fuel injection rack, and a second input connected to a fixed DC voltage source such as a potentiometer 85 connected between a voltage source and ground.
  • the potentiometer 85 is adjusted such that the output of the comparator 82 will change when the fuel injection rack is positioned for a minimum load.
  • the AND gate 83 When the output of the comparator 81 indicates that the engine speed has exceeded the preselected maximum value and the output of the comparator 82 indicates that the fuel injection rack is at a predetermined minimum load position, the AND gate 83 will apply a signal to the comparator 61 for causing the motor 20 to drive the valve to a fully closed position. Thus, there will be minimal exhaust gas recirculation under these conditions. This will prevent the engine from emitting a cloud of smoke when the engine is again accelerated.
  • the output 78 from the converter 77 is also connected to a third comparator 86.
  • a potentiometer 87- applies a fixed DC voltage to a second input of the comparator 86.
  • the potentiometer 87 is adjusted such that the output from the comparator 86 changes when the engine passes through a preselected midrange speed, such as 1,950 rpm. When this preselected speed is exceeded, the comparator 86 sinks current from an attenuator 88 and reduces the oscillator signal to the proximity probe 56, thereby shifting the linear curve along which the valve 14 is operated. As previously discussed, two typical curves are shown in the graph of FIG. 4 for the operation of the valve 14.
  • the maximum exhaust gas recirculation for one engine was found to be about 35% for no-load for providing a good balance between smoke and nitrogen oxide pollutants.
  • about 35% of the exhaust gas is recirculated for a no-load condition of the engine.
  • the recirculated exhaust gas is linearly decreased to 0% or to some other predetermined low level.
  • additional exhaust gas may be recirculated without having adverse affects on engine smoking.
  • exhaust gas recirculation system may also be adapted for use with other types of internal combustion engines, such as spark-ignited gasoline engines.
  • the conditions under which the exhaust gas recirculation is controlled will, of course, be modified for the requirements of any particular engine.
  • a sparkignited gasoline engine may require maximum recirculation at a mid-speed range rather than at minimum load and idle conditions.
  • an exhaust gas emission control system comprising, in combination, valve means for selectively recirculating a portion of the exhaust gas to the air intake, said valve means moving between a first position wherein a predetermined maximum amount of the exhaust gas is recirculated and a second position wherein a predetermined minimum amount of the exhaust gas is recirculated, means for generating an electric signal indicative of a load on the engine, and electrical means positioning said valve means at predetermined intermediate positions between said first and second positions in response to such signal for reducing the oxides of nitrogen present in the engine exhaust gas.
  • valve positioning means includes electrical control means for moving said valve means to said first position when the load on the engine is less than a predetermined value and for moving said valve means progressively towards said second position as the load progressively increases above such predetermined value.
  • An exhaust gas emission control system for an internal combustion engine as set forth in claim 2, and further including means for moving said valve means to said first position when the engine is running at less than a predetermined minimum speed.
  • An exhaust gas emission control system for an internal combustion engine as set forth in claim 3, and including means responsive to such electric signal and to the engine speed for moving said valve means to said second position when the load on the engine is less than a predetermined value and simultaneously the engine exceeds a predetermined speed.
  • An exhause gas emission control system for an internal combustion engine as set forth in claim 4, and further including means responsive to the speed of the engine for modifying said predetermined maximum amount of exhaust gas recirculated when said valve means is in said first position.
  • An exhaust gas emission control system for an internal combustion engine including means for generating an electric signal indicative of the position of said valve means, and wherein said valve positioning means includes an electric motor connected to drive said valve means, means for comparing said engine load signal and said valve position signal and means responsive to such comparison for controlling said valve drive motor.
  • valve positioning means further includes means responsive to said engine load signal for generating a third signal when the load on the engine is less than a predetermined minimum, and means for causing said valve drive motor to move said valve means to said first position in response to said third signal.
  • An exhaust gas emission control system for an internal combustion engine as set forth in claim 6, and further including means for generating an electric sig nal when the engine is running at less than a predetermined minimum speed, and means for causing said valve drive motor to move said valve means to said first position in response to said minimum speed signal.
  • An exhaust gas emission control system for an internal combustion engine as set forth in claim 6, and further including means for generating an electric signal when the load on the engine is less than a predetermined minimum, means for generating an electric signal when the engine speed exceeds a predetermined maximum, and means responsive to the simultaneous occurrence of said minimum load signal and said maximum speed signal for causing said valve drive motor to move said valve means to said] second position.
  • An exhaust gas emission control system for an internal combustion engine as set forth in claim 6, and further including means for generating a third electrical signal when the engine exceeds a predetermined speed, and means responsive to said third signal for increasing said predetermined maximum amount of exhaust gas recirculated when said valve means is in said first positron.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Exhaust-Gas Circulating Devices (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)
US447573A 1974-03-04 1974-03-04 Exhaust gas recirculation system for internal combustion engines Expired - Lifetime US3915134A (en)

Priority Applications (11)

Application Number Priority Date Filing Date Title
US447573A US3915134A (en) 1974-03-04 1974-03-04 Exhaust gas recirculation system for internal combustion engines
CA219,041A CA1015623A (en) 1974-03-04 1975-01-30 Exhaust gas recirculation system for internal combustion engines
DE19752508736 DE2508736A1 (de) 1974-03-04 1975-02-28 Auspuffgas-emmissions-regelsystem
AU78752/75A AU487245B2 (en) 1974-03-04 1975-03-03 Exhaust gas emission control system
IT20871/75A IT1033379B (it) 1974-03-04 1975-03-03 Sistema di controllo della emissione dei gas di scarico
ES435262A ES435262A1 (es) 1974-03-04 1975-03-04 Perfeccionamientos en los sistemas de regulacion de emisionde los gases de escape.
FR7506699A FR2263385B1 (enrdf_load_stackoverflow) 1974-03-04 1975-03-04
NL7502557A NL7502557A (nl) 1974-03-04 1975-03-04 Stelsel voor het regelen van de emissie van uitlaatgassen van een dieselmotor.
GB8832/75A GB1494687A (en) 1974-03-04 1975-03-04 Internal combustion engines
SE7502398A SE408081B (sv) 1974-03-04 1975-03-04 Styrningsanordning for att styra utsleppet av avgaser fran en forbrenningsmotor
JP50026438A JPS6011214B2 (ja) 1974-03-04 1975-03-04 内燃機関の排気ガス還流装置

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US447573A US3915134A (en) 1974-03-04 1974-03-04 Exhaust gas recirculation system for internal combustion engines

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US3915134A true US3915134A (en) 1975-10-28

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US (1) US3915134A (enrdf_load_stackoverflow)
JP (1) JPS6011214B2 (enrdf_load_stackoverflow)
CA (1) CA1015623A (enrdf_load_stackoverflow)
DE (1) DE2508736A1 (enrdf_load_stackoverflow)
ES (1) ES435262A1 (enrdf_load_stackoverflow)
FR (1) FR2263385B1 (enrdf_load_stackoverflow)
GB (1) GB1494687A (enrdf_load_stackoverflow)
IT (1) IT1033379B (enrdf_load_stackoverflow)
NL (1) NL7502557A (enrdf_load_stackoverflow)
SE (1) SE408081B (enrdf_load_stackoverflow)

Cited By (48)

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US4020809A (en) * 1975-06-02 1977-05-03 Caterpillar Tractor Co. Exhaust gas recirculation system for a diesel engine
US4026256A (en) * 1976-05-10 1977-05-31 Chrysler Corporation Engine exhaust gas recirculation (EGR) control system
US4044738A (en) * 1974-06-07 1977-08-30 Lucas Electrical Company Limited Pollution control arrangements for engines
US4051818A (en) * 1974-11-23 1977-10-04 Volkswagenwerk Aktiengesellschaft Device for obtaining signals for the control unit of an electronic fuel injection system
US4075994A (en) * 1972-06-02 1978-02-28 Texaco Inc. Internal combustion engine operation utilizing exhaust gas recirculation
US4085718A (en) * 1976-02-06 1978-04-25 Daimler-Benz Aktiengesellschaft Exhaust gas return system for auto-igniting internal combustion engines
US4128885A (en) * 1977-05-18 1978-12-05 Motorola, Inc. Digital circuitry for spark timing and exhaust gas recirculation control
US4141324A (en) * 1976-10-18 1979-02-27 United States Of America Low emission internal combustion engine
US4142493A (en) * 1977-09-29 1979-03-06 The Bendix Corporation Closed loop exhaust gas recirculation control system
US4157081A (en) * 1977-01-18 1979-06-05 Nissan Diesel Motor Co., Ltd. Recirculated exhaust gas control device for use in a diesel engine
US4161929A (en) * 1977-08-30 1979-07-24 Toyota Jidosha Kogyo Kabushiki Kaisha Exhaust gas recirculation control system for an internal combustion engine
US4164206A (en) * 1978-01-19 1979-08-14 The Bendix Corporation Closed loop programmable EGR with coolant temperature sensitivity
US4173205A (en) * 1977-11-28 1979-11-06 The Bendix Corporation Closed loop exhaust gas recirculation system
US4178903A (en) * 1977-08-17 1979-12-18 Toyota Jidosha Kogyo Kabushiki Kaisha Internal combustion engine with an auxiliary combustion chamber
US4196708A (en) * 1977-12-01 1980-04-08 Lucas Industries Limited Engine systems
US4286566A (en) * 1979-06-08 1981-09-01 Lucas Industries Limited Engine system
US4313415A (en) * 1979-06-14 1982-02-02 Nissan Motor Co., Ltd. Exhaust gas recirculation system in compression-ignition internal combustion engine
US4333438A (en) * 1978-03-22 1982-06-08 Automobiles Peugeot Device for recycling exhaust gases for a diesel engine
US4373497A (en) * 1981-09-21 1983-02-15 General Motors Corporation Exhaust gas recirculation control
US4378777A (en) * 1980-08-27 1983-04-05 Toyo Kogyo Co., Ltd. Internal combustion engine having exhaust gas recirculation system
US4378776A (en) * 1980-08-25 1983-04-05 Toyo Kogyo Co., Ltd. Internal combustion engine having exhaust gas recirculation system
US4411242A (en) * 1981-04-03 1983-10-25 Nippon Soken, Inc. Method and apparatus for controlling EGR in internal combustion engine
US4428355A (en) 1981-06-22 1984-01-31 Toyo Kogyo Co., Ltd. Exhaust gas recirculation control for internal combustion engines
US4455987A (en) * 1981-07-17 1984-06-26 Pierburg Gmbh & Co. Kg Method of and an arrangement for controlling return quantities of exhaust
DE3400313A1 (de) * 1983-01-10 1984-07-19 Ford-Werke AG, 5000 Köln Vorrichtung zur rezirkulationsregelung der auspuffgase eines dieselmotors
US4495929A (en) * 1981-02-19 1985-01-29 Mazda Motor Corporation Exhaust gas recirculation system for diesel engines
EP0620364A3 (en) * 1993-04-16 1999-01-07 Toyota Jidosha Kabushiki Kaisha Fuel-injection control device for a diesel engine
US6012437A (en) * 1998-07-06 2000-01-11 Eaton Corporation EGR system with improved control logic
US6029636A (en) * 1999-02-01 2000-02-29 Kiel; Lonn M. Air intake pre-heater
WO2002055856A3 (en) * 2000-12-15 2002-10-03 Detroit Diesel Corp Method/apparatus for controlling engine exhaust gas recirculation
US6463907B1 (en) 1999-09-15 2002-10-15 Caterpillar Inc Homogeneous charge compression ignition dual fuel engine and method for operation
EP1180589A3 (de) * 2000-08-18 2003-04-23 Steyr-Daimler-Puch Fahrzeugtechnik AG & CO. KG Verfahren und Vorrichtung zur Steuerung der Abgasrückführung einer Luftverdichtenden Verbrennungskraftmaschine
US6575149B2 (en) 2001-09-21 2003-06-10 Siemens Vdo Automotive, Incorporated Exhaust gas regulator including a non-contact sensor
US20030111066A1 (en) * 2001-11-08 2003-06-19 Andre Veinotte Modular exhaust gas recirculation assembly
US20040177838A1 (en) * 2003-03-14 2004-09-16 Siemens Vdo Automotive Inc. Electric actuator assembly and method for controlling an exhaust gas recirculation assembly
US20040177839A1 (en) * 2003-03-14 2004-09-16 Siemens Vdo Automotive Inc. Modular exhaust gas recirculation assembly
US20040182369A1 (en) * 2002-12-18 2004-09-23 Siemens Vdo Automotive Inc. Fuel vapor purge control assembly and methods of assembling and controlling same
US6843239B2 (en) 2001-12-21 2005-01-18 Caterpillar Inc. High speed exhaust gas recirculation valve
US20050061017A1 (en) * 2003-09-18 2005-03-24 Lee Wook Yong Ice supplying device of refrigerator
WO2005031132A1 (en) * 2003-09-30 2005-04-07 Westport Research Inc. Method and apparatus for providing for high egr gaseous-fuelled direct injection internal combustion engine
US6935320B2 (en) 2001-11-08 2005-08-30 Siemens Vdo Automotive Inc. Apparatus and method for exhaust gas flow management of an exhaust gas recirculation system
US20070095131A1 (en) * 2005-11-02 2007-05-03 Denso Corporation Abnormal condition detecting system for engine
US20080110436A1 (en) * 2006-11-13 2008-05-15 Holley Performance Products, Inc. Air valve and method of use
RU2349782C2 (ru) * 2006-11-10 2009-03-20 Виль Моисеевич Капитанский Дизель с впускным и выпускным трактами, соединенными между собой перепускной трубой
US20110093182A1 (en) * 2008-05-08 2011-04-21 Borgwarner Beru Systems Gmbh Estimating engine parameters based on dynamic pressure readings
US20130025576A1 (en) * 2010-04-14 2013-01-31 Borgwarner Inc. Multifunction valve
CN103346755A (zh) * 2013-07-02 2013-10-09 天津精通控制仪表技术有限公司 一种滤波模块
US12158121B2 (en) 2022-08-24 2024-12-03 Caterpillar Inc. Engine system configured for unburned hydrocarbon (HC) collection from exhaust port

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JPS5218531A (en) * 1975-08-05 1977-02-12 Nissan Motor Co Ltd Exhaust gas reflux control system
DE2803750A1 (de) * 1978-01-28 1979-08-02 Bosch Gmbh Robert Verfahren und einrichtung zur kraftstoffzumessung bei brennkraftmaschinen
FR2420659A1 (fr) * 1978-03-22 1979-10-19 Peugeot Dispositif de recyclage des gaz d'echappement pour moteur diesel
FR2443582A2 (fr) * 1978-12-05 1980-07-04 Peugeot Dispositif de recyclage des gaz d'echappement pour moteur diesel
JPS5554658A (en) * 1978-10-17 1980-04-22 Nippon Soken Inc Electronic controller for internal-combustion engine
JPS56159554A (en) * 1980-05-12 1981-12-08 Nissan Motor Co Ltd Exhaust gas recirculation control system for diesel engine
JPS5713241A (en) * 1980-06-30 1982-01-23 Diesel Kiki Co Ltd Fuel injector
DE3032381C2 (de) * 1980-08-28 1986-07-24 Robert Bosch Gmbh, 7000 Stuttgart Elektronische Steuereinrichtung für eine Brennkraftmaschine mit Selbstzündung
US4428354A (en) * 1982-06-21 1984-01-31 General Motors Corp. Diesel engine fuel limiting system
JPS6328718A (ja) * 1986-07-22 1988-02-06 Diesel Kiki Co Ltd 車両用空気調和装置

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US3807376A (en) * 1970-12-17 1974-04-30 Bosch Gmbh Robert Apparatus for regulating the recycling of partially combusted fuels in an internal combustion engine
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Cited By (64)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4075994A (en) * 1972-06-02 1978-02-28 Texaco Inc. Internal combustion engine operation utilizing exhaust gas recirculation
US4044738A (en) * 1974-06-07 1977-08-30 Lucas Electrical Company Limited Pollution control arrangements for engines
US4051818A (en) * 1974-11-23 1977-10-04 Volkswagenwerk Aktiengesellschaft Device for obtaining signals for the control unit of an electronic fuel injection system
US4020809A (en) * 1975-06-02 1977-05-03 Caterpillar Tractor Co. Exhaust gas recirculation system for a diesel engine
US4085718A (en) * 1976-02-06 1978-04-25 Daimler-Benz Aktiengesellschaft Exhaust gas return system for auto-igniting internal combustion engines
US4026256A (en) * 1976-05-10 1977-05-31 Chrysler Corporation Engine exhaust gas recirculation (EGR) control system
US4141324A (en) * 1976-10-18 1979-02-27 United States Of America Low emission internal combustion engine
US4157081A (en) * 1977-01-18 1979-06-05 Nissan Diesel Motor Co., Ltd. Recirculated exhaust gas control device for use in a diesel engine
US4128885A (en) * 1977-05-18 1978-12-05 Motorola, Inc. Digital circuitry for spark timing and exhaust gas recirculation control
FR2406088A1 (fr) * 1977-05-18 1979-05-11 Motorola Inc Circuit de commande d'allumage et de recirculation des gaz d'echappement
US4178903A (en) * 1977-08-17 1979-12-18 Toyota Jidosha Kogyo Kabushiki Kaisha Internal combustion engine with an auxiliary combustion chamber
US4161929A (en) * 1977-08-30 1979-07-24 Toyota Jidosha Kogyo Kabushiki Kaisha Exhaust gas recirculation control system for an internal combustion engine
US4142493A (en) * 1977-09-29 1979-03-06 The Bendix Corporation Closed loop exhaust gas recirculation control system
US4173205A (en) * 1977-11-28 1979-11-06 The Bendix Corporation Closed loop exhaust gas recirculation system
US4196708A (en) * 1977-12-01 1980-04-08 Lucas Industries Limited Engine systems
US4164206A (en) * 1978-01-19 1979-08-14 The Bendix Corporation Closed loop programmable EGR with coolant temperature sensitivity
US4333438A (en) * 1978-03-22 1982-06-08 Automobiles Peugeot Device for recycling exhaust gases for a diesel engine
US4286566A (en) * 1979-06-08 1981-09-01 Lucas Industries Limited Engine system
US4313415A (en) * 1979-06-14 1982-02-02 Nissan Motor Co., Ltd. Exhaust gas recirculation system in compression-ignition internal combustion engine
US4378776A (en) * 1980-08-25 1983-04-05 Toyo Kogyo Co., Ltd. Internal combustion engine having exhaust gas recirculation system
US4378777A (en) * 1980-08-27 1983-04-05 Toyo Kogyo Co., Ltd. Internal combustion engine having exhaust gas recirculation system
US4495929A (en) * 1981-02-19 1985-01-29 Mazda Motor Corporation Exhaust gas recirculation system for diesel engines
US4411242A (en) * 1981-04-03 1983-10-25 Nippon Soken, Inc. Method and apparatus for controlling EGR in internal combustion engine
US4428355A (en) 1981-06-22 1984-01-31 Toyo Kogyo Co., Ltd. Exhaust gas recirculation control for internal combustion engines
US4455987A (en) * 1981-07-17 1984-06-26 Pierburg Gmbh & Co. Kg Method of and an arrangement for controlling return quantities of exhaust
US4373497A (en) * 1981-09-21 1983-02-15 General Motors Corporation Exhaust gas recirculation control
DE3400313A1 (de) * 1983-01-10 1984-07-19 Ford-Werke AG, 5000 Köln Vorrichtung zur rezirkulationsregelung der auspuffgase eines dieselmotors
US4479473A (en) * 1983-01-10 1984-10-30 Ford Motor Company Diesel engine emission control system
EP0620364A3 (en) * 1993-04-16 1999-01-07 Toyota Jidosha Kabushiki Kaisha Fuel-injection control device for a diesel engine
US6012437A (en) * 1998-07-06 2000-01-11 Eaton Corporation EGR system with improved control logic
US6029636A (en) * 1999-02-01 2000-02-29 Kiel; Lonn M. Air intake pre-heater
US6463907B1 (en) 1999-09-15 2002-10-15 Caterpillar Inc Homogeneous charge compression ignition dual fuel engine and method for operation
EP1180589A3 (de) * 2000-08-18 2003-04-23 Steyr-Daimler-Puch Fahrzeugtechnik AG & CO. KG Verfahren und Vorrichtung zur Steuerung der Abgasrückführung einer Luftverdichtenden Verbrennungskraftmaschine
WO2002055856A3 (en) * 2000-12-15 2002-10-03 Detroit Diesel Corp Method/apparatus for controlling engine exhaust gas recirculation
US6575149B2 (en) 2001-09-21 2003-06-10 Siemens Vdo Automotive, Incorporated Exhaust gas regulator including a non-contact sensor
US20030111066A1 (en) * 2001-11-08 2003-06-19 Andre Veinotte Modular exhaust gas recirculation assembly
US6928994B2 (en) 2001-11-08 2005-08-16 Siemens Vdo Automotive, Inc. Modular exhaust gas recirculation assembly
US6935320B2 (en) 2001-11-08 2005-08-30 Siemens Vdo Automotive Inc. Apparatus and method for exhaust gas flow management of an exhaust gas recirculation system
US6843239B2 (en) 2001-12-21 2005-01-18 Caterpillar Inc. High speed exhaust gas recirculation valve
US7107970B2 (en) 2002-12-18 2006-09-19 Siemens Vdo Automotive Inc. Fuel vapor purge control assembly and methods of assembling and controlling same
US20040182369A1 (en) * 2002-12-18 2004-09-23 Siemens Vdo Automotive Inc. Fuel vapor purge control assembly and methods of assembling and controlling same
US20040177838A1 (en) * 2003-03-14 2004-09-16 Siemens Vdo Automotive Inc. Electric actuator assembly and method for controlling an exhaust gas recirculation assembly
US20040177839A1 (en) * 2003-03-14 2004-09-16 Siemens Vdo Automotive Inc. Modular exhaust gas recirculation assembly
US7201159B2 (en) * 2003-03-14 2007-04-10 Siemens Canada Limited Electric actuator assembly and method for controlling an exhaust gas recirculation assembly
US6907868B2 (en) 2003-03-14 2005-06-21 Siemens Vdo Automotive, Inc. Modular exhaust gas recirculation assembly
US20050061017A1 (en) * 2003-09-18 2005-03-24 Lee Wook Yong Ice supplying device of refrigerator
WO2005031132A1 (en) * 2003-09-30 2005-04-07 Westport Research Inc. Method and apparatus for providing for high egr gaseous-fuelled direct injection internal combustion engine
US7302918B2 (en) 2003-09-30 2007-12-04 Westport Power Inc. Method and apparatus for providing for high EGR gaseous-fuelled direct injection internal combustion engine
US20060260585A1 (en) * 2003-09-30 2006-11-23 Sandeep Munshi Method and apparatus for providing for high egr gaseous-fuelled direct injection internal combustion engine
CN1871414B (zh) * 2003-09-30 2010-05-26 韦斯特波特动力股份有限公司 向气态燃料直喷式内燃机提供高废气再循环的方法与设备
EP1687516A4 (en) * 2003-09-30 2010-05-12 Westport Power Inc METHOD AND DEVICE FOR PROVIDING A GAS INTERNAL COMBUSTION ENGINE WITH DIRECT INJECTION AND HIGH EGR
US7671601B2 (en) * 2005-11-02 2010-03-02 Denso Corporation Abnormal condition detecting system for engine
US20070095131A1 (en) * 2005-11-02 2007-05-03 Denso Corporation Abnormal condition detecting system for engine
RU2349782C2 (ru) * 2006-11-10 2009-03-20 Виль Моисеевич Капитанский Дизель с впускным и выпускным трактами, соединенными между собой перепускной трубой
US20080110436A1 (en) * 2006-11-13 2008-05-15 Holley Performance Products, Inc. Air valve and method of use
US7658177B2 (en) 2006-11-13 2010-02-09 Holley Performance Products, Inc. Air valve and method of use
US7591245B2 (en) 2006-11-13 2009-09-22 Holley Performance Products, Inc. Air valve and method of use
US20090101104A1 (en) * 2006-11-13 2009-04-23 Holley Performance Products, Inc. Air valve and method of use
US20080110435A1 (en) * 2006-11-13 2008-05-15 Oswald Baasch Air valve and method of use
US20110093182A1 (en) * 2008-05-08 2011-04-21 Borgwarner Beru Systems Gmbh Estimating engine parameters based on dynamic pressure readings
US20130025576A1 (en) * 2010-04-14 2013-01-31 Borgwarner Inc. Multifunction valve
CN103346755A (zh) * 2013-07-02 2013-10-09 天津精通控制仪表技术有限公司 一种滤波模块
CN103346755B (zh) * 2013-07-02 2015-08-26 天津精通控制仪表技术有限公司 一种滤波模块
US12158121B2 (en) 2022-08-24 2024-12-03 Caterpillar Inc. Engine system configured for unburned hydrocarbon (HC) collection from exhaust port

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DE2508736A1 (de) 1975-09-18
SE408081B (sv) 1979-05-14
SE7502398L (enrdf_load_stackoverflow) 1975-09-05
FR2263385A1 (enrdf_load_stackoverflow) 1975-10-03
GB1494687A (en) 1977-12-14
IT1033379B (it) 1979-07-10
CA1015623A (en) 1977-08-16
NL7502557A (nl) 1975-09-08
JPS50125128A (enrdf_load_stackoverflow) 1975-10-01
ES435262A1 (es) 1976-12-16
AU7875275A (en) 1976-09-09
FR2263385B1 (enrdf_load_stackoverflow) 1980-10-17
JPS6011214B2 (ja) 1985-03-23

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