US3828742A - Engine control system - Google Patents

Engine control system Download PDF

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Publication number
US3828742A
US3828742A US00247651A US24765172A US3828742A US 3828742 A US3828742 A US 3828742A US 00247651 A US00247651 A US 00247651A US 24765172 A US24765172 A US 24765172A US 3828742 A US3828742 A US 3828742A
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US
United States
Prior art keywords
signal
engine
speed
rotational speed
output signal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00247651A
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English (en)
Inventor
R Weis
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Caterpillar Inc
Original Assignee
Caterpillar Tractor Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Caterpillar Tractor Co filed Critical Caterpillar Tractor Co
Priority to US00247651A priority Critical patent/US3828742A/en
Priority to CA167,676A priority patent/CA997038A/en
Priority to JP4580273A priority patent/JPS5614856B2/ja
Priority to BE130436A priority patent/BE798746A/fr
Application granted granted Critical
Publication of US3828742A publication Critical patent/US3828742A/en
Assigned to CATERPILLAR INC., A CORP. OF DE. reassignment CATERPILLAR INC., A CORP. OF DE. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: CATERPILLAR TRACTOR CO., A CORP. OF CALIF.
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P3/00—Measuring linear or angular speed; Measuring differences of linear or angular speeds
    • G01P3/42—Devices characterised by the use of electric or magnetic means
    • G01P3/44—Devices characterised by the use of electric or magnetic means for measuring angular speed
    • G01P3/48—Devices characterised by the use of electric or magnetic means for measuring angular speed by measuring frequency of generated current or voltage
    • G01P3/4802—Devices characterised by the use of electric or magnetic means for measuring angular speed by measuring frequency of generated current or voltage by using electronic circuits in general
    • G01P3/4805—Devices characterised by the use of electric or magnetic means for measuring angular speed by measuring frequency of generated current or voltage by using electronic circuits in general by using circuits for the electrical integration of the generated pulses
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P1/00—Details of instruments
    • G01P1/07—Indicating devices, e.g. for remote indication
    • G01P1/08—Arrangements of scales, pointers, lamps or acoustic indicators, e.g. in automobile speedometers
    • G01P1/10—Arrangements of scales, pointers, lamps or acoustic indicators, e.g. in automobile speedometers for indicating predetermined speeds
    • G01P1/103—Arrangements of scales, pointers, lamps or acoustic indicators, e.g. in automobile speedometers for indicating predetermined speeds by comparing the value of the measured signal with one or several reference values

Definitions

  • the 1 3/19 l 90/4 control system includes a control device which continuously monitors engine speed sensed through a mag- [56] References cued netic pickup means and causes engine shutdown by UNITED STATES PATENTS means of an engine shutdown device when an over- 1,470,277 10/1923 Loftus 123/ 1 18 speed condition occurs.
  • the control device 1 irzgover 123/148 S actuates a warning device when an underspeed condimson non occurs 3,291,246 12/1966 Colling et al.
  • REFERENCE VOLTAGE COMPARATOR AMPLIFIER I REFERENCE VOLTAGE METER I I I I I I I I I v I I I I I I I I I I I I I I I I I I I ENGINE CONTROL SYSTEM CROSS-REFERENCE TO RELATED APPLICATION Cross-reference is made to related Application Ser. No. 141,230, filed May 7, 1971 now US. Pat. No. 3,714,509, issued Jan. 20, 1973.
  • This invention relates to a speed monitor and control system for engines. More particularly, this invention concerns a control system having a control device for causing engine shutdown when an overspeed condition occurs and activates a warning device or alternatively causes engine shutdown when an underspeed condition occurs.
  • speed control systems are used in this engine test environment to prevent undesirable overspeed or underspeed conditions. This is due to the fact that when an engine undergoing testing, or in a permanent stationary installation for that matter, begins to overspeed, it is necessary that the engine be shut down as soon as possible to prevent damage to the engine from occurring. Conversely, engine damage can also occur during an underspeed condition since engine auxiliary equipment, i.e., cooling pump, cooling fan, lube oil pump, etc., is run at too slow a speed to efficiently carry away heat generated by the engine.
  • engine auxiliary equipment i.e., cooling pump, cooling fan, lube oil pump, etc.
  • optical meter control relays as a control device for activating the engine shutdown device during an overspeed condition. Actuation of this and other 40 functions is initiated by the optical meter relay when a light path between a lamp and a photocell is interrupted at a predetermined point on the meter by the meter indicator.
  • This type of switching arrangement has an inherent time lag between actual engine speed and meter-indicated speed due to the inclusion of mechanical components having inertia effects.
  • the present invention comprises an all-solid-state as opposed to mechanical speed control device for monitoring and controlling speeds of an engine, such as an internal combustion engine, during testing.
  • a magnetic pickup device on the engine feeds a signal to the speed control device where it is processed and fed to a pair LII of comparator amplifiers.
  • a reference voltage source associated with each comparator amplifier provides a signal proportional to the maximum speed and minimum speed desired, respectively.
  • the comparator amplifiers continuously compare the reference voltage input with the speed signal originating from the magnetic pickup device.
  • an engine shutdown device is signal by the first comparator amplifier to shut down the engine.
  • a warning device is activated to call the operators attention to the underspeed condition or shut down the engine, as desired.
  • FIG. I is an overall schematic view of the instant invention in its normal working environment
  • FIG. 2 is a schematic diagram of a portion of the same in somewhat greater detail.
  • FIG. 3 is a schematic circuit diagram of the same.
  • FIG. I shows generally at 1.0 a speed control system of the present invention.
  • the magnetic pickup device 12 is mounted on the engine 14 in close proximity to an inner gear (not shown) in the engine.
  • this pickup device or means could be mounted on a dynamometer (not shown) which would be coupled to the output shaft of the engine.
  • a signal proportional to the engine speed is transmitted from magnetic pickup 12 to a speed control device 16 having a power supply 18 connected thereto.
  • the power supply may be as is conventional in the art.
  • the speed control device continuously compares actual engine speed with both a maximum desired as well as a minimum desired engine speed. If the actual engine speed exceeds the desired maximum, a signal is transmitted to the engine shutdown device 20 to shut down the engine.
  • This engine shutdown device could be one of various types of devices including a dynamometer, fuel shutoff, air shutoff, or any combination of these devices.
  • the dynamometer application would, of course, result in the stalling of the engine to accomplish shutdown.
  • This dynamometer may be as commercially available from the General Electric Company as a Water Gap Induction 5 Dynamometer Model No. IG774. As an alternate, a
  • a signal would be transmitted from the control device 16 to warning device 22.
  • This device could be a light or horn which would signal the operator to take appropriate remedial action.
  • an engine shutdown device like the aforementioned device, could be substituted so as to shut down the engine when the underspeed condition occurs.
  • magnetic pickup 12 mounted adjacent to a rotating internal gear (not shown) on the engine, senses the speed of the rotating gear and transmits a sine wave signal as shown in block diagram 12.
  • the sine wave signal is sent to squaring amplifier 24 of speed control device 16 where it is amplified and changed to a square wave for each sine wave.
  • the signal is sent to a differentiator 26 where the square wave is differentiated to produce sharp positive and negative pulses, as shown in block diagram 26.
  • the positive pulse resulting from the differentiator 26 is sent to a monostable multivibrator 28, which produces a pulse or signal of fixed width and height while the negative pulse is sent to ground.
  • the monostable multivibrator output signal is then sent to a filter integrator circuit 30, which is an integrated-circuit operational amplifier with a resistance capacitance feedback loop.
  • the circuit integrates the positive signal pulses over a fixed time period and produces as an output a DC voltage level as a function of the frequency of the pulses received.
  • the filter integrator circuit As the output signal leaves the filter integrator circuit, it takes two paths 32 and 34, with signal 32 going to a meter range selector 36 while signal 34 continues on to take two separate paths 38 and 40.
  • the output of the meter range selector 36 is sent to meter 42 for visual readout of engine speed. This visual indication of the engine speed is used for operator reference only and does not exercise any control over the machine functions, so that any time lag between the meter and actual engine operation is not important for the efficient operation of the engine.
  • the signal on path 38 is identical with the signal on path 40 and that both are proportional to engine speed.
  • the signal on path 38 is input to a first comparator amplifier 44 while the signal of path 40 is input to a second comparator amplifier 46.
  • a first or a maximum speed reference voltage mechanism 48 produces a maximum speed reference voltage signal which is input along path 50 to comparator amplifier 44.
  • a minimum speed reference voltage mechanism 52 sends a minimum speed voltage signal along path 54 to comparator amplifier 46.
  • the first comparator amplifier 44 controls the high-speed function and the second comparator amplifier 46 controls the low-speed function.
  • comparator amplifiers 44 and 46 In operation, as long as the actual engine speed sensed by magnetic pickup device 12 is intermediate to the maximum and minimum desired speeds, comparator amplifiers 44 and 46 will not transmit signals. However, when the output of filter integrator transmitted along paths 34, 38, 40 exceeds either one of the present reference voltage signals, the output of the comparator amplifier will change state. This will energize one of the associated relays 55 or 56 which will, in turn, cause either the engine shutdown device 20 or the warning device 22 to be activated depending upon the amplifier involved.
  • Reference voltage mechanisms 48 and 52 are digivider/digidecade-type devices which have a five-decade, ten-position capacity for accurate variation of the particular engine device which the control device controls. In the alternative, these may be preset, nonvariable devices.
  • Power source 18 may be any standard-design power source.
  • the power supply can use standard 1 l0-volt AC power which is converted to a $12 and a 4-volt DC output for operating various components of the control system.
  • a-speed monitor and control system comprising: sensing means positioned so as to'measure rotational speed of the engine, means generating an actual speed signal proportional to sensed rotational speed, said signal being directed along two separate paths, first reference means creating a first reference signal proportional to a desired maximum rotational speed, first comparator means receiving the signal from one of said paths for comparing said actual speed signal with said first reference signal, engine shutdown means for shutting down the engine when said actual speed signal passes said maximum rotational speed, second reference means creating a second reference signal proportional to a desired minimum rotational speed which is less than said maximum rotational speed, second comparator means receiving the signals from the other of said paths for comparing said actual speed signal with said second reference signal, and warning means operable by said second comparator means for indicating a speed below said desired minimum, and wherein said means for generating an actual speed signal comprises means generating an output signal in the form of a sine wave, means converting said sine wave output signal into a square wave output signal for each sine wave, means differentiating said square

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Testing Of Engines (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)
  • Control Of Vehicle Engines Or Engines For Specific Uses (AREA)
  • Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
  • Combined Controls Of Internal Combustion Engines (AREA)
  • Ignition Installations For Internal Combustion Engines (AREA)
US00247651A 1972-04-26 1972-04-26 Engine control system Expired - Lifetime US3828742A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
US00247651A US3828742A (en) 1972-04-26 1972-04-26 Engine control system
CA167,676A CA997038A (en) 1972-04-26 1973-04-02 Engine control system
JP4580273A JPS5614856B2 (fr) 1972-04-26 1973-04-24
BE130436A BE798746A (fr) 1972-04-26 1973-04-26 Systeme de commande de moteur

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US00247651A US3828742A (en) 1972-04-26 1972-04-26 Engine control system

Publications (1)

Publication Number Publication Date
US3828742A true US3828742A (en) 1974-08-13

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ID=22935759

Family Applications (1)

Application Number Title Priority Date Filing Date
US00247651A Expired - Lifetime US3828742A (en) 1972-04-26 1972-04-26 Engine control system

Country Status (4)

Country Link
US (1) US3828742A (fr)
JP (1) JPS5614856B2 (fr)
BE (1) BE798746A (fr)
CA (1) CA997038A (fr)

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4090480A (en) * 1977-05-03 1978-05-23 Kasiewicz Stanley Joseph Electrical overspeed control for an engine
US4155419A (en) * 1976-09-16 1979-05-22 Vdo Adolf Schindling Ag Apparatus for controlling the traveling speed of a motor vehicle
US4205639A (en) * 1977-06-25 1980-06-03 Diesel Kiki Co., Ltd. Anti-stall device in a diesel engine
US4220868A (en) * 1977-05-27 1980-09-02 Nissan Motor Company, Limited Method of and system for controllably connecting load to generator
US4235181A (en) * 1978-04-27 1980-11-25 Oregon Link, Inc. Automatic blower control system for inboard marine engines
US4250846A (en) * 1976-12-17 1981-02-17 Thomson-Csf Electronic ignition system and an internal combustion engine equipped with this system
US4262641A (en) * 1978-11-24 1981-04-21 W. R. Grace & Co. Combined RPM limiter, and electronic tachometer with shift point indicator
US4355607A (en) * 1980-09-08 1982-10-26 Zemco, Inc. Safety disengagement device for automotive speed control system
EP0066682A2 (fr) * 1981-06-06 1982-12-15 Dr. Johannes Heidenhain GmbH Dispositif de positionnement
JPS5990743A (ja) * 1982-10-22 1984-05-25 アウデイ・エヌエスウ−・オ−ト・ウニオ−ン・アクチエンゲゼルシヤフト 混合気圧縮火花点火式、燃料噴射式内燃機関の回転数を制限する方法
US4488527A (en) * 1982-10-09 1984-12-18 Vdo Adolf Schindling Ag Device for controlling the speed of travel of an automotive vehicle
US4495913A (en) * 1983-03-15 1985-01-29 Dana Corporation Ignition current sensor for an electronic speed control system
US4510899A (en) * 1979-09-17 1985-04-16 Muncie Power Product Inc. Electronic overspeed switch
USRE32955E (en) * 1979-09-17 1989-06-20 Muncie Power Products, Inc. Electronic overspeed switch
US4856613A (en) * 1987-08-10 1989-08-15 General Safety Research, Inc. Safety engine load sensing system
US5203302A (en) * 1992-01-27 1993-04-20 Tecumseh Products Company Overload warning apparatus for internal combustion engines
US5600558A (en) * 1994-08-12 1997-02-04 Caterpillar Inc. Data exception reporting system
US5642284A (en) * 1994-08-12 1997-06-24 Caterpillar Inc. Maintenance monitor system
US5857159A (en) * 1994-08-12 1999-01-05 Caterpillar Inc. Data recording and display system
US6898512B1 (en) * 2004-01-06 2005-05-24 Detroit Diesel Corporation Overspeed shut down test for electronically controlled engine
US20110248511A1 (en) * 2009-10-05 2011-10-13 Alyssa Marlenee Generator set cooling control system
US20130269654A1 (en) * 2012-04-13 2013-10-17 GM Global Technology Operations LLC Method of controlling a diesel engine
US20180173559A1 (en) * 2015-07-01 2018-06-21 Hitachi Automotive Systems, Ltd. Electronic Control Device and Stack Usage Method

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5853657A (ja) * 1981-09-25 1983-03-30 Kubota Ltd エンジンの燃料漏出防止安全装置

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1470277A (en) * 1922-04-24 1923-10-09 Andrew B Loftus Automatic regulator
US2656827A (en) * 1951-10-03 1953-10-27 Outboard Marine & Mfg Co Idling control for two-cycle engines
US3153746A (en) * 1961-07-03 1964-10-20 Duane E Atkinson Internal combustion engine overspeed control
US3291246A (en) * 1964-09-29 1966-12-13 Gen Motors Corp Delayed automatic lock-up speed control and speed warning system
US3572302A (en) * 1969-04-16 1971-03-23 Are Inc Internal combustion engine speed limiting apparatus
US3601103A (en) * 1969-10-13 1971-08-24 Ladell Ray Swiden Engine-condition-responsive cutoff apparatus
US3623464A (en) * 1969-06-10 1971-11-30 Outboard Marine Corp Ignition safety circuit
US3722485A (en) * 1971-03-09 1973-03-27 Diesel Kiki Co Electronic governor for fuel-injection type internal combustion engines

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1470277A (en) * 1922-04-24 1923-10-09 Andrew B Loftus Automatic regulator
US2656827A (en) * 1951-10-03 1953-10-27 Outboard Marine & Mfg Co Idling control for two-cycle engines
US3153746A (en) * 1961-07-03 1964-10-20 Duane E Atkinson Internal combustion engine overspeed control
US3291246A (en) * 1964-09-29 1966-12-13 Gen Motors Corp Delayed automatic lock-up speed control and speed warning system
US3572302A (en) * 1969-04-16 1971-03-23 Are Inc Internal combustion engine speed limiting apparatus
US3623464A (en) * 1969-06-10 1971-11-30 Outboard Marine Corp Ignition safety circuit
US3601103A (en) * 1969-10-13 1971-08-24 Ladell Ray Swiden Engine-condition-responsive cutoff apparatus
US3722485A (en) * 1971-03-09 1973-03-27 Diesel Kiki Co Electronic governor for fuel-injection type internal combustion engines

Cited By (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4155419A (en) * 1976-09-16 1979-05-22 Vdo Adolf Schindling Ag Apparatus for controlling the traveling speed of a motor vehicle
US4250846A (en) * 1976-12-17 1981-02-17 Thomson-Csf Electronic ignition system and an internal combustion engine equipped with this system
US4090480A (en) * 1977-05-03 1978-05-23 Kasiewicz Stanley Joseph Electrical overspeed control for an engine
US4220868A (en) * 1977-05-27 1980-09-02 Nissan Motor Company, Limited Method of and system for controllably connecting load to generator
US4205639A (en) * 1977-06-25 1980-06-03 Diesel Kiki Co., Ltd. Anti-stall device in a diesel engine
US4235181A (en) * 1978-04-27 1980-11-25 Oregon Link, Inc. Automatic blower control system for inboard marine engines
US4262641A (en) * 1978-11-24 1981-04-21 W. R. Grace & Co. Combined RPM limiter, and electronic tachometer with shift point indicator
US4510899A (en) * 1979-09-17 1985-04-16 Muncie Power Product Inc. Electronic overspeed switch
USRE32955E (en) * 1979-09-17 1989-06-20 Muncie Power Products, Inc. Electronic overspeed switch
US4355607A (en) * 1980-09-08 1982-10-26 Zemco, Inc. Safety disengagement device for automotive speed control system
US4594538A (en) * 1981-06-06 1986-06-10 Dr. Johannes Heidenhain Gmbh Monitoring circuit for positioning device
EP0066682A3 (en) * 1981-06-06 1984-07-18 Dr. Johannes Heidenhain Gmbh Positioning device
EP0066682A2 (fr) * 1981-06-06 1982-12-15 Dr. Johannes Heidenhain GmbH Dispositif de positionnement
US4488527A (en) * 1982-10-09 1984-12-18 Vdo Adolf Schindling Ag Device for controlling the speed of travel of an automotive vehicle
JPS5990743A (ja) * 1982-10-22 1984-05-25 アウデイ・エヌエスウ−・オ−ト・ウニオ−ン・アクチエンゲゼルシヤフト 混合気圧縮火花点火式、燃料噴射式内燃機関の回転数を制限する方法
US4495913A (en) * 1983-03-15 1985-01-29 Dana Corporation Ignition current sensor for an electronic speed control system
US4856613A (en) * 1987-08-10 1989-08-15 General Safety Research, Inc. Safety engine load sensing system
US5203302A (en) * 1992-01-27 1993-04-20 Tecumseh Products Company Overload warning apparatus for internal combustion engines
US5642284A (en) * 1994-08-12 1997-06-24 Caterpillar Inc. Maintenance monitor system
US5600558A (en) * 1994-08-12 1997-02-04 Caterpillar Inc. Data exception reporting system
US5857159A (en) * 1994-08-12 1999-01-05 Caterpillar Inc. Data recording and display system
US6898512B1 (en) * 2004-01-06 2005-05-24 Detroit Diesel Corporation Overspeed shut down test for electronically controlled engine
US20110248511A1 (en) * 2009-10-05 2011-10-13 Alyssa Marlenee Generator set cooling control system
US8550038B2 (en) * 2009-10-05 2013-10-08 Cummins Power Generation Ip, Inc. Generator set cooling control system
US20130269654A1 (en) * 2012-04-13 2013-10-17 GM Global Technology Operations LLC Method of controlling a diesel engine
CN103375278A (zh) * 2012-04-13 2013-10-30 通用汽车环球科技运作有限责任公司 控制柴油发动机的方法
US9091228B2 (en) * 2012-04-13 2015-07-28 GM Global Technology Operations LLC Method of controlling a diesel engine
CN103375278B (zh) * 2012-04-13 2016-02-24 通用汽车环球科技运作有限责任公司 控制柴油发动机的方法
US20180173559A1 (en) * 2015-07-01 2018-06-21 Hitachi Automotive Systems, Ltd. Electronic Control Device and Stack Usage Method

Also Published As

Publication number Publication date
JPS4954706A (fr) 1974-05-28
BE798746A (fr) 1973-10-26
CA997038A (en) 1976-09-14
JPS5614856B2 (fr) 1981-04-07

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Date Code Title Description
AS Assignment

Owner name: CATERPILLAR INC., 100 N.E. ADAMS STREET, PEORIA, I

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:CATERPILLAR TRACTOR CO., A CORP. OF CALIF.;REEL/FRAME:004669/0905

Effective date: 19860515

Owner name: CATERPILLAR INC., A CORP. OF DE.,ILLINOIS

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:CATERPILLAR TRACTOR CO., A CORP. OF CALIF.;REEL/FRAME:004669/0905

Effective date: 19860515