US3414734A - Automatic engine starting system - Google Patents

Description

s. KONRAD AUTOMATIC ENGINE STARTING SYSTEM Dec. 3, 1968 Filed Feb. 24, 1967 \NVENTOR p /z/ .MO/VAAO By 74 M) ATTORNEY United States Patent M 3,414,734 AUTOMATIC ENGINE STARTING SYSTEM Philip S. Konrad, Prospect Heights, Ill., assignor to Borg- Warner Corporation, Chicago, 111., a corporation of Illinois Filed Feb. 24, 1967, Ser. No. 618,422 3 Claims. (Cl. 290-38) ABSTRACT OF THE DISCLOSURE An auxiliary automatic starting circuit for an automotive vehicle includes a circuit breaker having a heater element which is in parallel with the starting system and is energized through a resistor to control the cranking interval of the engine when cranked by the automatic circuit and to quickly disable the automatic circuit by shorting out the resistor when the gear selector is moved out of Park position preventing unauthorized movement of the vehicle while under the control of the automatic circuit.

Summary of the invention The present invention relates generally to a starting circuit for an automotive vehicle engine and more particularly to an improved auxiliary automatic starting circuit therefor.

Prior automatic starting circuits for automotive vehicles have included complex electro-mechanical devices and/ or sophisticated electronic components to protect the battery against undue discharge where the engine fails to start within a prescribed time interval, and to protect against theft of the vehicle when the engine is operating by means of the automatic circuit.

It is an object of the present invention to provide an automatic starting circuit incorporating improved simplified reliable electrical components which provides protection against unauthorized movement of the vehicle when the engine is under the control of the automatic circuit and which limits the time interval during which the engine can be cranked by the automatic circuit to a predetermined maximum.

Brief description of the drawing The figure is a schematic drawing of an electrical control system for an internal combustion engine employing the present invention.

Description 0 the preferred embodiments Referring now to the drawing, the broken line 10, for convenience of description, encloses certain conventional components of an automotive vehicle engine including an ignition system 11, astarter system 12, and portions of acarburetor apparatus 13 having a throttle linkage. Theenclosure 14 indicates a conventional ignition and starting switch such as the usual key operated switch used in motor vehicles. The broken line 16 encloses certain additiona1 circuit components, to be described more fully hereinafter, illustrating the present invention.

A battery 17 is connected to conventional starting andigition switch 14 by meas of leads 18 and 19.Switch 14 is connected to ignition system 11 bylead 21, and to startingsystem 12 by means oflead 22. Startingsystem 12 includes asolenoid 23, and a starter motor 25 connected to battery 17 byleads 24 and 26. Ignition system 11 includes a spark coil 27, abreaker 28 and adistributor 29. The circuit thus far described includes conventional com- 3,414,734 Patented Dec. 3, 1968 ICC ponents of automotive vehicles, switch 14 being effective to supply energy to ignition and startingsystems 11 and 12 upon manual operation thereof as by an ignition key.

According to the present invention an improved arrangement ofauxiliary starting circuit 39 is provided for automatically starting the engine and maintaining it in operation responsive to the occurrence of a preselected condition such as temperature drop.Auxiliary starting circuit 39 includes a circuit breaker 31, portions of agear selector switch 41, a condition sensitive switch 42 and avacuum switch 43 connected in series between battery 17 andstarter system 12.

*Circuit breaker 31 includescontacts 32, 33 arranged to be bridged by amanual pushbotton 34 upon actuation thereof, contact 32 being connected to battery 17 byleads 37, 26, and 18. Aheater element 36 is incorporated in circuit breaker 31 so as to movecontact 33 laterally away frompushbutton 34 after a predetermined current flow therethrough. When the contacts of circuit breaker 31 have been thus opened,pushbutton 34 cannot be used to manually override the device until sufiicient cooling has occurred. If desired, an indicator lamp 38 may be connected betweencontact 33 and ground to provide a visual indication thatauxiliary circuit 39 is operatively connected to battery 17 through circuit breaker 31.

Gear selector switch 41 includes a first stage havingactive contacts 44 and 46 inauxiliary starting circuit 39 and a second stage having active contacts 47, 48 in atiming circuit 51 forheater element 36. As shown schematically, switch 41 is remotely actuated by means of relay 72 which in turn is controlled byswitch 73.Switch 73 is actuated by means of acam 52 connected to gearselector 53. Relay 72 and switch 73 are arranged to closecontacts 44 and 46 inauxiliary starting circuit 39, and to close contacts 47 and 48 intiming circuit 51 whengear selector 53 is in Park position. Aspring 54 is provided to openswitch 73 whengear selector 53 is moved to other than Park position. Whenswitch 73 isopen contacts 44 and 56 ofswitch 41 are closed in the first stage andcontacts 47 and 49 are closed in the second stage.Switch 41 may also be a double pole double throw switch actuated directly bycam 52 ofgear selector 53. Theswitch 73 and relay 72 may be used to enhance installation in certain types of vehicles.Contact 56 in the first stage is connected to contact 49 in the second stage bylead 69.

Condition sensitive switch 42 is a thermal switch arranged to sense the temperature in the water jacket of a water cooled engine or the air temperature in an enclosure associated with the vehicle which becomes warm after operation of the engine. Such enclosures may be the passenger compartment of the vehicle in which a heater is operative when the engine is running or may be the engine enclosure itself. Switch 42 is arranged to closecontacts 57, 58 inauxiliary starting circuit 39 responsive to the occurrence of a preselected low temperature and to open the circuit responsive to a preselected higher temperature.

Vacuum switch 43 includes contacts 59, 61, closed when the engine is inoperative or cranking, and open when the engine is operating at idle speed or greater. A vacuum motor '62, communicating with the engine manifold, is arranged to move in one direction under the urgence ofspring 63 and in the other direction when the engine has developed suflicient vacuum to overcome the spring force.Vacuum motor 62 is preferably connected to the throttle control by means of a flexible member such as a bead chain or a one-way clutching device and to switch 43 so that the switch is closed and the throttle is open when the engine is inoperative or cranking, and so thatswitch 43 is opened and the throttle is returned to idle speed setting when the engine is in operation. The opening and subsequent closing of the throttle is effective to condition the automatic choke for operation before cranking begins and generally duplicates the manual actuation of the vehicle accelerator pedal before cranking the engine when starting by means of the conventional key operated starting switch. The use of a one-way clutching member or flexible link for connectingvacuum motor 62 with the throttle control permits normal operation of the vehicle by means of the accelerator pedal.

Timing circuit 51 is connected in electrical parallel 'with starting system '12 and is in series circuit with bothauxiliary starting circuit 39 and the conventional starting circuit includingstarting switch 14 and leads 18, 19, and 22.Timing circuit 51 includes a droppingresistor 64, contacts 47 and 48 ofgear selector switch 41 and theheater element 36 of circuit breaker 31. The resistance value ofresistor 64 is selected in accordance with the operating characteristics ofheater element 36 and the time interval during which the engine is to be cranked. For example, resistance values of from 2 to 3 ohms have been found to provide a cranking cycle of 8 to 10 seconds which is satisfactory for various well-known passenger automobiles having 12 volt electrical systems.

Adiode 66 is connected betweenauxiliary circuit 39 and ignition system 11 byleads 67, 68 biased to pass current fromauxiliary circuit 39 to ignition system 11 and to block passage of current in the reverse direction. In normal operation of the vehicle, the operator may, on occasion, open the throttle to accelerate the vehicle, which causes a momentary loss of vacuum allowingvacuum switch 43 to close momentarily.Diode 66 prevents flow of current from ignition system 11 to thestarter system 12 through the momentarily closedvacuum switch 43.

Auxiliary starting circuit 39 is conditioned for automatic operation by manually placing the gear selector of the vehicle in Park position and by manually depressingpushbutton 34 which is preferably latched in the On or Set position. Indicator lamp 38 is energized to give a visual indication that the circuit is in condition for automatic operation. Thereafter, when the temperature drops to the preselected low value, thermal switch 42 is closed.Vacuum switch 43 is normally closed when the engine is inoperative such that a circuit is completed from battery 17 to startersolenoid 23 for cranking the engine. As soon as the engine begins to run,vacuum switch 43 is opened breaking the circuit to startersolenoid 23 and to timingcircuit 51. In the case of a spark ignition engine, current is supplied to ignition system 11 by theauxiliary circuit 39 throughdiode 66 even though thestarter system 12 has been disengaged byvacuum switch 43. The engine will then continue to run until a preselected higher temperature is reached at which thermal switch 42 openscontacts 57, 58 thereby opening the circuit to ignition system 1 1 to stop the engine.

If the engine should fail to start after a predetermined interval of cranking, the current flow throughresistor 64 andheater element 36 is effective to open circuit breaker 31 to disableauxiliary circuit 39. 'If an operator should neglect to disableauxiliary starting circuit 39 before starting the vehicle by means of theconventional key switch 14, or if unauthorized movement of the vehicle is attempted while the engine is running under control ofauxiliary starting circuit 39, theswitch 41 functions as an anti-theft and safety device. Whengear selector 53 is moved [from Park position,cam 52 rotates so thatcontacts 44 and 56 are connected to each other and so thatcontacts 47 and 49 and connected to each other. In this position,switch 41 opensauxiliary circuit 39 ahead oflead 67 anddiode 66 so that no current is supplied to ignition system 11. In addition, droppingresistor 64 is shorted out so that heater 3 6 is connected directly to battery 17 throughauxiliary circuit 39. The application of current from battery 17 directly toheater element 36 results in the rapid tripping of circuit breaker 31 to openauxiliary circuit 39. Once tripped, the circuit breaker must go through an interval of cooling before it can be manually reset further frustrating unauthorized tampering with the vehicle. In the case of a vehicle which can be cranked by means of the key switch only when the gear selector is in Park position, thelead 69 can be connected directly toauxiliary circuit 39 eliminating the first stage ofswitch 41 includingcontacts 44, '46, 56.Heater 36 would then open circuit breaker 31 to prevent current flow to ignition system 11. However, since many vehicles can be cranked by means of the key switch when the gear selector is in either Neutral or Park positions, it is preferred to provide theadditional contacts 44, 46, 56. Thus if the operator should start the vehicle when the gear selector is in Neutral, the closedcontacts 44 and '56 serve to open the circuit breaker 31, while theopen contacts 44, 46 prevent the continued application of battery voltage acrossheater element 36 fromstarting system 12, throughlead 69.

While preferred and alternate embodiments of the invention have been shown and described, it is to be understood that variations thereof are included within the spirit of the invention and the scope of the following claims.

I claim:

.1. In an electrical control system for an internal com bustion engine adapted for an automotive vehicle having a battery, an electric starter system, and a gear selector including a Park position for controlling motion thereof, said control system including a manually operable starting circuit connected between said battery and starter system the improvement comprising; an auxiliary starting circuit connected between said battery and starter system bypassing said manually operable starting circuit for automatically starting said engine responsive to a preselected condition, said auxiliary circuit including a condition sensitive switch, in series with a circuit breaker effective to open said auxiliary circuit responsive to a preselected current flow; and a heating circuit in parallel with said starter system including a resistor having a predetermined value connected in series with a heater element for said circuit breaker, regulating current flow to said heater element for opening said auxiliary circuit after a predetermined interval of engine cranking without starting when said engine is being caused to be cranked by means of said auxiliary starting circuit.

2. The combination according to claim :1 in which said electrical control system includes an engine ignition system selectively connectable to said battery by means of said manually operable starting circuit, and in which a diode is connected between said ignition system and said auxiliary starting circuit biased 'for passing current from said auxiliary starting circuit to said ignition system, said diode blocking passage of current from said ignition system to said starter system through portions of said auxiliary circuit.

3. The combination according to claim 1 in which said electrical control system includes an engine ignition system, said heating circuit including a selector switch actuated by said gear selector having a first contact connected to said resistor, and a second contact connected to said heater element, said first and second contacts being closed when said gear selector is in Park preventing current flow to said ignition system, said selector switch preventing unauthorized movement of said vehicle while under control of said auxiliary starting circuit.

No references cited.

A. HARRY LEVY, Primary Examiner.

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