US1776683A

US1776683A - Automatic controlling system for internal-combustion engines

Info

Publication number: US1776683A
Application number: US157405A
Authority: US
Inventors: Elwood T Larkin
Original assignee: Individual
Current assignee: Individual
Priority date: 1926-12-27
Filing date: 1926-12-27
Publication date: 1930-09-23
Anticipated expiration: 1947-09-23

Description

E. T. LARKIN Sept. 23, 1930.

AUTOMATIC CONTROLLING SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed Dec. 27,

a 5: 3 Q A Patented Sept. 23, 1930 UNITED STATES PATENT OFFICE AUTOMATIC CONTROLLING SYSTEM FOR INTERNAL-COMBUSTION ENGINES Application filed December 27, 1926. Serial No. 157,405.

This invention relates to systems for automatically controlling the operation of internal combustion engines, and more particularly to the starting and stopping thereof.

The objects of this invention are to provide a system of this kind by means of which an internal combustion engine may be started and stopped without requiring any attention by an operative; also to provide a system of this kind with a control switch which, when closed, completes the ignition circuit of the engine, and a relay starting circuit, which is interrupted when the engine attains a predetermined speed, the control switch when opened stopping the engine by breaking the ignition circuit; also to provide a system of this kind of means of'which the ignition devices of the engine are controlled automatically so that the ignition or spark is retarded during the starting of the engine and advanced after the engine has been started; also to provide a system of this kind by means of which a priming charge of fuel is supplied to the engine during the starting thereof; also to provide a system of this kind in which the operation of the starting motor of the engine is automatically stopped when the engine attains a predetermined speed; also to provide a system of this kind in which the operation of the starting motor is interm ttent; also to provide a system of this kind in which the starting motor circuit is interrupted after the engine has been started; also to provide a system of this kind with control devices of improved construction for effecting the retarding of the ignition spark before the starting motor circuit is closed; also to provide a system of this kind which is capable of being operated at a distance remote from the engine itself; also to provide a system of this kind by means of which the supply of fuel to the engine is automatically maintained during the starting and operation of the engine and interrupted when the engine is stopped; also to improve systems of this kind in other respects hereinafter specified.

The single figure of the accon- 'ianying drawing shows diagrammatically a system embodying my invention for automatically controlling the operation of internal combustion engines.

ln many instances where fans, blowers, pumps, machines or other devices are driven by electric motors or other sources of power, it is frequently desirable to have an independent auxiliary driving unit, such as an internal combustion engine, which can be operated in case the main driving unit ceases to operate or becomes overloaded and it is frequently desirable to have the auxiliary source of power placed into operation immediately upon the arising of the necessity therefor. For example in mine ventilation, fans or blowers may be operated by electric motors and if for any reason the supply of power to the electric motor becomes interrupted it is necessary that an auxiliary source of power be immediately placed into opera tion, and the system shown in the drawings is intended to render an internal combustion engine usable as an auxiliary source of power in instances of this kind. It will be understood, however, that it is not intended to limit this invention for use in connection with operating blowers since thesystcm may be employed in any other instance Where it is desired to automatically start and stop an internal combustion engine, and the system may also be manually operated in such a manner that the mere closing of a switch causes the automatic starting of an internal combustion engine.

In the accompanying drawing, A represents a control switch which may be actuated either manually or automatically in any suitable manner to close a series of circuits, the switch shown including a conductor a which is adapted to connect a pair of fixed contacts or terminals 4 and 5, a conductor a which completes a circuit between two con tacts or terminals 6 and 7 when the switch is closed, and a conductor a which functions in a similar manner in connection with two contacts or terminals 8 and 9. The drawing illustrates by way of example one manner in which the switch A may be actuated automatically, namely by means of a solenoid B having a core b connected with the movable member A of the switch. In case the system contacts with the terminals 4:, 5, 6, 7, 8 and 9.

This means for actuating the switch member A is merely shown to illustrate one embodiment of this invention and it will be obvious that the switch member B may be actuated by means of a thermostatic device, a float device, or any other control means.

The contacts 6 and 7 are connected respectively with conductors l0 and 11, which conductors are adapted to open a fuel supply valve when the terminals 6 and 7 are connected. For this purpose in the construction shown a solenoid 12 is provided with which the conductor 10 is connected, the core of the solenoid being connected to a fuel supply valve 13 in such a way that when the current is flowing through the solenoid 12, the -valve 13 is open to supply fuel to the engine. The other conductor 11 connects with a conductor 14 leading from a battery or other source of power C, and the other end of the solenoid 12 is connected to a conductor 15 leading to another conductor 16 connected with the other terminal of the battery C. Any other means for placing the engine in communication with a supply of fuel may be used, or in cases where it is unnecessary to use a valve in the fuel line or where the valve can be left open at all times, this circuit may be entirely omitted from the system.

The control switch A is preferably employed to close the ignition circuit of the engine when the control switch is closed, and to break the ignition circuit when the switch is open, so that the opening ofthe switch causes the engine to stop. In the construction shown for this purpose the terminal 4 is connected with a conductor 18 which leads to the engine ignition system which is not shown in the drawings for the reason that any suitable ignition system may be used for this purpose, the ignition switch being preferably operated from a battery D, said ignition being grounded. The internal combustion engine may be of any suitable or desired construction and is not shown in the drawings since it is of itself no part of this invention, and the various instrumentalities used for starting the engine may also be of well known construction and are merely diagrammatically indicated on the drawing.

The terminal 5 connects with a conductor 19 which in turn connects with a conductor 20 leading to the positive terminal of the battery D, the other terminal being rounded. Consequently current from the battery I) flows through the conductors 20 and 19 to the terminal 5 and when the control switch A is closed current flows through the part a of the control switch to the terminal +1 and conductor 18 to the ignition system and then through the ground to the negative terminal of the battery 1). This circuit remains energized as long as the control switch A remains closed so that when this switch is again opened, for example, by the resumption of the flow of current through the relay B, the engine is immediately stopped by the breaking of the ignition circuit, and the opening of the control switch A will also cause the solenoid 12 to be deenergized so that the fuel valve 13 is closed by any suitable means, not shown.

The remaining steps leading to the automatic starting of the engine are controlled by means of a relay circuit connected with the terminals 8 and 9 of the control switch, and preferably though not necessarily, through a relay master switch E, and this circuit is adapted to be interrupted when the engine has attained a speed somewhat greater than that at which it may be turned over by its starting motor. For this purpose a conductor 201 connects the terminal S) with one end of a solenoid 21 of the master switch E, the other terminal of the solenoid 21 being connected by means of a conductor 22 to the conductor 16 leading to the positive terminal of the battery C. The other terminal 8 of the control switch is connected by means of a conductor 24 to a contact 25 of a suitable switch actuated by means responsive to the speed of the engine. such as a governor controlled switch E which is diagrammatically illustrated to include a governor 26 which moves the contact or switch terminal 25 out of engagement with a fixed contact or terminal 27 after the engine to which the gov ernor is connected reaches a predetermined speed. The stationary contact 27 of the governor switch is connected by means of conductors 28 to a conductor lat which leads to the negative terminal of the battery C. Consequently the master switch E will only be closed when the engine is standing still or operating at a low speed, and as soon as the engine attains a speed somewhat beyond that at which it can be turned over by the starting motor. the circuit through the master switch is broken by means of the governor control switch. Consequently the starting devices, which are all actuated by this relay circuit will be no longer required after the engine has been started and are consequently rendered inoperative by the breaking of this relay circuit by the governor controlled switch E. a

The master switch E, in the form shown in the drawing, includes a movable switch member 30 which is connected to a core 31, the movable member 30, when the solenoid 21 is energized, being in its upper position in contact with switch terminals 32, 33, 34 and 35. Other means for interrupting the flow of current to the relay circuit connected with the terminals 8 and 9 of the control switch when the engine has been started may be employed if desired.

The closing of the relay circuit effects the intermittent operation of one or more switches or relays for intermittently actuating severaldevices used for starting the engine. In the particular construction shown for this purpose, the negative terminal of the battery C is connected through conductor 14 and a conductor 37 to the contact 34, and when the master switch E is closed current flows from the contact 34 through a part of the master switch to the terminal or contact 35 and thence through a conductor 38 to the fixed terminal or contact 39 of an intermittently operating relay switch, the movable contact 40 of this switch being intermittently opened and closed by any suitable means. In the particular construction illustrated, a retarded relay in the form of a solenoid and dash pot is employed for producing the intermittent opening and closing of this switch, a solenoid 41 having one terminal connected with the movable switch member 40 and the other terminal connected through a conductor 42 and conductor 16 to the battery C. The solenoid 41 has a core 44 provided at its lower end with a plunger which operates in a dash pot 45 of any usual or suitable construction. Consequently when the movable switch member 40 contacts with the fixed terminal or switch member 39, current will flow through the solenoid 41 drawing the core 44 upwardly against the action of the dash pot, so that the upward movement of the core will be comparatively slow. When the flow of current through the solenoid 41 is interrupted, the core 44 and plunger connected therewith will move in the opposite direction in the dash pot until they reach the lower limit of travel. The reciprocatory movement of the core 44 may be communicated to the movable switch member 40 in any suitable or desired manner. In the particular construction shown the movable switch member 40 is connected with the core 44 of the solenoid by means of a spring 46 which moves past the pivotal axis of the movable switch member 40 during' the movement of the core 44 of the solenoid. When the spring 46 is below the pivotal axis of the movable switch member as shown in the drawings, the spring will tend to swing the movable switch member into its circuit closing position. WVhen on the other hand the core 44 of the solenoid is raised so that the spring 46 swings above the pivot of the movable switch member 40, the spring 46 will exert an upward pull on the movable switch member and move the same into its open circuit position as indicated in dotted lines on the drawings.

Other movable switch members may be actuated by the same core 44 of the solenoid, one such member 49 being shown in the drawings. This movable switch member 49 is also connected with the core of the solenoid by means of a spring 50 and the movable switch member 49 is adapted to engage with a fixed contact or terminal 51. The movable switch member 49 operates differently from the mov able switch member 40 in that the downward movement of the core 44 of the solenoid causes this switch member 49 to be opened while the upward movement of the core closes the switch.

The alternate opening and closing of the movable switchmember 49 may control the intermittent supply of current to a part of the starting mechanism of the engine, and in the particular construction shown this intermittent current is employed to operate a plunger or piston F of a primer pump, the primer pump being of a reciprocatory type and not being shown in the drawings. The plunger of piston F is connected with a core 54 of a solenoid 55. Current for actuating the solenoid 55 passes through a circuit including the conductor 14 and a conductor 56 connected with the movable switch member 49, and a conductor 57 connecting the fixed switch member or contact 51 with a terminal of the solenoid 55, the other terminal of the solenoid being connected with a conductor 58 leading to the positive terminal of the battery. The supply of current to the solenoid 55 causes the plunger F of the primer pump to reciprocate in one direction and when the current in the solenoid is interrupted, the plunger is returned to its original position. This reciprocation of the plunger supplies fuel directly to the intake manifold of the engine or to any other part thereof where it can be readily vaporized to hasten the starting of the engine. Since the reciprocatory movement of the core 44 of the solenoid is controlled through the relay circuit including the master switch E it will be obvious that when this relay circuit is: opened due to the fact that the engine has attained the necessary speed to actuate the governor switch E, the core 44 of the solenoid will fall by gravity into the position shown in the full lines in the drawings, in which position the movable switch member 49 is out of engagement with the terminal or contact 51 so that the primer pump will then be no longer in operation.

The other steps in the starting of the internal combustion engine are effected by another intermittently operating switch. which in the particular construction illustrated is controlled from a separate solenoid 60 cooperating with the dash pot 61, this solenoid being also connected by means of the conductor 42 and the conductor 16 to the positive terminal of the battery 0. The other terminal of the solenoid 60 is connected through a movable switch member 62, a fixed terminal or contact 63, and conductor 64, to the fixed contact 32 of the master switch E, and consequently when the master switch is closed current will flow through the sole noid 60 through a circuit including the conductors 14 and 37 and stationary switch con-' tacts 33 and 32 of the master switch E. The solenoid 60 controls the intermittent opening and closing of a switch including a movable switch member 66 cooperating with a fixed switch memberjor contact 67 and actuated by means of a spring 68 connected with the core of the solenoid 60 in the same manner as described in connection with the switch actuated by the core 44 of the solenoid 41. The movable switch member 66 connected to one of the terminals of the battery C, for example, the negative terminal by means of conductors 70, 56 and 14, and the fixed contact or terminal 67 of the switch is connected by means of a conductor 71 to a solenoid 72 or other device for alternately closing the starting circuit of the starting motor *of theengine and also operating the spark and throttle control of the engine. The other terminal of the solenoid 72 is connected by means of the conductor 58 to the positive terminal of the battery C. The solenoid 72 has a core 74 which is connected to one arm of an engine control lever G which may control the advancing and retarding of the ignition spark or the throttle valve of the engine or both of these inst-rumentalities. In the particular construction shown this engine control lever is pivoted at 7 5 and the other arm 76 of the lever is normally pulled against the action of the solenoid 7 2 by a coil spring 77 or other suitable means, into a position which this engine control lever occupies during the normal operation of the engine. Consequently the energizing of the solenoid 72 will cause the core 74 to be drawn in a direction to swing the lever G about-its pivot 7 5 against the action of the spring 77 into the dotted line position shown in the draw ings, in which position the spark will be retarded for starting and the throttle will be in a position to facilitate starting of the engine.

In the particular construction shown the energizing of the solenoid 72 is also intended to effect the starting of the starting motor of the engine and this may be done in any suitable or desired manner. As shown in the drawings the combined spark control and throttle lever G is connected to a movable switch member 7 9 by means of a link 80, the movable switch member 79 being grounded as indicated and being normally held in an open position shown 1n full lines on the drawing by means of the spring 77. The energizing of the solenoid 72, however, causes the movable switch member 79 to be moved into a position in which it makes contact with a fixed switch member or terminal 81 connected by means of a conductor 82 with a solenoid 83 of a starting switch 84, the other terminal of the solenoid 83 being connected by means of conductors 85 and 20 to the positive terminal of the starting battery D. The closing of the starting switch 84 causes current to flow from the positive terminal of the starting battery D through conductor 20 and the starting switch 84 to the starting motor H of the engine, the other terminal of the 'motor being connected to the negative ter-- minal of the battery by means of a conductor 86 and is grounded at 87. Consequently the closing of the movable switch member 66 intermittently causes an intermittent energizing of the solenoid 72 so that the starting motor of the engine is operated at intervals and at the same time the spark is retarded and the throttle lever placed in a position for starting. The intermittent operation of the starting motor prevents over- .heating of this motor in case the engine is difiicult to start. When the engine is started and attains a speed slightly be 0nd that which the starting motor is capable of imparting to the engine, the governor switch 27 causes the master switch E to open so that the switch member 66 will also be moved to its open position and thus interrupt the operation of the starting motor as well as permit the spark to be advanced and the throttle lever to be moved to its running position. It will be understood that the starting motor is connected with the engine in the usual manner, by means of automatically engaging gears or a ratchet device (not shown).

If desired, the system may also be provided with an alarm device which is to be actuated when the engine is being started. This may easily be eflected by means of a solenoid operated switch I which closes a circuit including an alarm device K. In the particular construction shown the solenoid switch I is actuated by means of a solenoid 88 connected in parallel with the solenoid 21 of the master switch E so that the alarm device will be actuated as long as the engine is being started. As soon, however, as the engine has been started and is in operation, the governor controlled switch E will cause the flow of current to solenoids 21 and 88 to be interrupted and thus discontinue the actuation of the alarm K. Any other alarm circuit may be used in connection with the starting system or the alarm device may be entirely eliminated, if desired.

Whenever conditions are restored to normill, 'for example by restoring the flow of current to the control solenoid B, the switch A will be returned to its normal or open position, thus causing the opening of the ignition circuit of the internal combustion engine by opening the circuit between the terminals 4 and 5, and shutting oil' of the gasoline valve by opening the circuit between the terminals 6 and 7, so that the operation of the internal combustion engine is automatically stopped.

It will be understood that the master switch E may be eliminated in case the control switch A is located near the engine to be started, in which case the two solenoids 41 and 60 and the intermittently operating switch members 40 and 62 may be connected in parallel in the relay circuit including the fixed terminals 8 and 9 of the control switch and the governor switch E. In case the control switch is located at a considerable distance from the engine to be started, it is desirable to use a master switch, such, for example, as the switch E described, since the amount of current required to actuate the master switch is considerably less than that required to actuate the two solenoids 41 and 60, so that the line losses may be reduced by using a master switch.

The system described has the advantage in that both the starting and stopping of the internal combustion engine takes place entirely automatically. Furthermore the system operates so that the operation of the starting motor takes place after the gasoline valve is opened and after the ignition circuit is completed, due to the fact that an interval of time is required before the solenoid 60 moves the switch member 66 into its circuit closing position. Furthermore the closing of the circuit through the starting motor can be effected only when the spark control lever G is moved into its retarded position so that damage due to starting the engine with an advanced spark is positively avoided. By causing the starting motor to operate intermittently the starting of the engine can be eilected without danger of overheating the startlng motor, as might be the case if this motor were operated continuously until the engine is started. By using a separate battery for actuating a number of the solenoids or relays, the full flow of current from the starting motor battery D is available for starting and ignition.

I claim as my invention:

1. In a system for starting an internal combustion engine, the combination of a starting motor. a starting motor circuit, an ignition circuit. a control switch for complcting the ignition circuit of the engine, a device which is placed into operation by said control switch and which first retards the spark of the ignition system and then complates a circuit through the starting motor of the engine, means operated independently of said switch when the engine has attained a predetermined speed for interrupting the circuit through the starting motor of the engine, and means actuated by the interrupting of the starting motor circuit for advancing said spark when the engine is started.

2. In a system for automaticallv starting an internal combustion engine, the combination of a starting motor, a starting motor circuit, an ignition circuit, a control switch which when closed completes the ignition circuit of the engine, a retarded and intermittently operating relay energized by the'closing of said control switch for closing said starting motor circuit, which circuit is intermittently closed and opened by said relay, and means for interrupting the operation of said relay to open the starting motor circuit after the engine has attained a predetermined speed.

3. In a system for starting an internal combustion engine, the combination of a starting motor, a starting motor circuit, an

ignition circuit, control means for completing the ignition circuit of the engine, a retarded relay to which current is supplied when the ignition circuit is closed, and a device actuated by said retarded relay and which is connected to impart movements simultaneously to an engine operating lever and to a switch for completing the circuit through the starting motor.

4. In a system for starting an internal combustion engine, the combination of a starting motor, a starting motor circuit, an ignition circuit, control means for completing the ignition circuit of the engine, a re tarded relay to which current is supplied when the ignition circuit is closed, a solenoid having a movable core, an engine control lever connected with the core so as to be moved into an engine starting position when the core is drawn into the solenoid, a switch for closing said circuit through the starting motor, and a connection between said lever and said switch to cause the switch to be closed after the lever has been moved into its starting position.

5. In a system for starting an internal combustion engine, the combination of a starting motor, a starting motor circuit, an ignition circuit, meansfor completing the ignition circuit of the engine, a retarded relay to which current is supplied when the ignition circuit is closed, a solenoid having a movable core, an engine control lever connected with the core so as to be moved into an engine starting position when the core is drawn'into the solenoid, a switch for closing the circuit through the starting motor, a connection between said lever and said switch to cause the switch to be closed after the lever has ben moved into its starting position, and a device responsive to the speed of the engine and which breaks the circuit to said retarded relay when the engine has attained a predetermined speed.

6. In an ignition system for an internal combustion engine. the combination of a starting motor, a starting motor circuit, an ignition circuit, a control switch which when closedlcomplctes said ignition circuit, a relay circuit completed by the closing of said control switch, a priming device for supplying fuel to the engine which is actuated by. the closing of said relay circuit, an engine control lever yieldingly held in a position which it should occupy when the engine is running, a device for moving said engine control lever into a starting position and closing the circuit through the starting motor of the engine and actuated when said relay circuit is closed, and means actuated when the engine reaches a predetermined speed for opening said relay circuit and thereby permitting said engine control lever to move to its running position and said starting motor circuit to be opened.

7. In a system for automatically starting an internal combustion engine, the combination of a starting motor, an ignition circuit, a control switch which when closed completes the ignition circuit of the engine, a master switch which is closed by the closing of said control switch, a circuit including a retarded relay which is closed when said master switch is closed, a circuit closed by said retarded relay for supplying current to said starting motor, an engine control lever yieldingly held in a position which it should 0ccupy when the engine is running, a device actuated by the circuit of said retarded relay for moving said control lever into a starting position, and means which operate when the engine has attained a predetermined minimum speed for opening said master switch.

8. In a system for automatically starting an internal combustion engine, the combination of a starting motor, an ignition circuit, a control switch which when closed completes the ignition circuit of the engine, a pair of retarded relays energized by the closing of said control switch, a starting motor circuit which is closed by one of said retarded relays after said ignition circuit is closed, a priming device actuated by means of a circuit closed by said other retarded relay. and means for interrupting the operation of said retarded relays after the engine has attained a predetermined speed.

9. In a system for automatically starting an internal combustion engine, the combination of a starting motor, an ignition circuit, a control switch which when closed completes the ignition circuit of the engine, a master switch which is closed by the closing of said control switch, a pair of circuits closed by said master switch and each including a retarded relay, a circuit including said starting motor which is closed by one of said retarded relays, a circuit including means for actuating a priming device, which circuit is closed by said other retarded relay, and means for opening said master switch after the engine has been started.

10. In a starting system for an internal combustion engine, the combination of a starting motor, a starting motor circuit, an ignition circuit, a control switch for completing a circuit through the ignition circuit of the engine, means actuated by said control switch for automatically and intermittently supplying current to the starting motor, and means operating independently of said control switch for stopping the starting motor when the engine has attained a predetermined speed.

ELWOOD 'I LARKIN.