US1928152A - Control device for engine driven generators - Google Patents

Description

Sept. '26, 1933. H. D. GUMPPER 1,928,152

CONTROL DEVICE FOR ENGINE DRIVEN GENERATORS Filed-Jan. 22, 1931 F""""" I l INVENTOR ATTO RN EYS Patented Sept. 26, 1933 PATENT OFFICE "(CONTROL ,DEVICE FOR ENGINE DRIVEN GENERATORS Harold D. Gumpper, Detroit, Mich., assignor to Marjorie Teakle Gumpper, Detroit, Mich.

Application January 22, 1931. Serial No. 510,500

Claims. (Cl. 290-17) This invention pertains to means for controlling the speed of a prime mover in driving an electric generator, in such a. manner that the speedof the prime, mover will be much slower 5 whenjelectric power is not being used, and may be automatically increased upon the application of an external electrical loador upon the manual closing of an externalcontrol switch. This is accomplished by means of a voltage regulating device consisting of an electrical governor capable of maintaining both a constant high operating voltage and a constant low no load voltage. Thus, where the load is intermittent, saving of power as well as wear on the prime mover and electric generator are possible, due tothe much slower speed of the prime mover when operating the generator at no load voltage. Furthermore, due to the maintained no load voltage'being held constant by the electric governoryvoltage pick up of the 20 generator upon application of an external load is much more rapid than would otherwiseresult if the generator voltage fell too low at no load.

A further objectis to provide a simple device for the purpose, not liable to get out of order and which may be readily applied in use, and having certain other new and useful features, hereinafter set forth and all as moreparticularly pointed out in the appended claims, reference being had to the accompanying drawing in which- Figure 1 is asideelevation of an internal combustion engine, the crankshaft of whichis direct connected to' an electric generator indicated in dotted lines, and showing in elevation, a governor and the manner of. connecting the same to the engine and also showing its electrical connections to the generator and to a motor indicated in outline and driven by generator output current; and

Fig. 2 is a longitudinal section through a governor and showing its connection to a throttle device of the engine with its electrical connections to motor and generator indicated diagrammatically.

As shown in Figure 1, A indicates a prime mover or internal combustion engine of the usual construction, having the usual crank shaft B indicated in dotted lines and to which an electric generator C of the usual construction and also indicated in dotted lines, is direct connected in Lin 5 any suitable manner. The engine A is provided with the usual intake manifold D to which a carbureter E is connected in the usual manner.

To control the voltage output of the generator C, the speed of the engine A is controlled by an electric governor, indicated as a whole by the numeral 1, which is rigidly supported in any suitable manner at one side of the engine adjacent the uptake pipe of the manifold D and in which pipe is a throttle valve 2 indicated in dotted lines andto the outer end of the stem of which throttle, is secured a lever 3. This lever is connected at its free end by a link 4, with one end of a plunger or movable core member 5 slidable within an axial guide tube 6 in the casing 7 of the governor and in which casing are mounted two solenoids or wire coils, one within the other, the inner coil 8 being wound about the tube 6, and the outer coil 9 wound about and insulated from the inner coil 8. One end of the axial tube 6 is provided with a screw 12 which passes through the closed end of the tube and bears against a stop 11, which in turn bears against one end of a compression spring 10. A lock nut 13 is provided for clamping the screw 12in any desired position. The other end of the compression spring bears against the plunger 5, tending to move it axially out of tube 6 and thereby causing lever 3 to move throttle valve 2 from a closed to an open position.

Coil member 8 is shown as electrically connected in shunt with the governor C to line 17 which leads to terminal of the governor, and to line 18 which leads-to terminal 16 0f said governor. Thus, when this generator armature is revolving, an electrical current will pass through coil member 8- forming a solenoid efiect which will tend to move the plunger 5 axially into the tube 6, against the action of spring 10. The balance that is established'between the solenoid action of the coil 8 upon plunger 5 and of spring 10 acting against plunger 5 will control the opening of throttle 2. As the voltage of the generator increases, the magnetic pull of solenoid coil 8 increases, moving the plunger inward against the spring, and as the voltage of the generator falls 01f, the pull of solenoid 8 weakens and the spring 10 moves the plunger outward. Thus the speed of engine A is controlled by the voltage generated at terminals 15 and 16 of the generator.

In order that the generated voltage across terminals 15 and 16 of the generator C may be increased upon the application of an external load, I have provided an additional winding on the governor 1, shown as coil 9 in Figure 2. An external load shown as a motor indicated by 14 in Figure 2 is connected by means of line 19 to terminal 15, and by line 20 to terminal 16 of the generator.

A switch, shown as 23, is inserted in line 20 to open and close the motor circuit. Coil 9 is connected by means of line 22 to terminal 15 of the generator and by line 21, which leads as shown to a point in line 20 between switch 23 and the motor 14. The polarity of leads 21 and 22 coming out of coil 9 are such that when switch 23 is closed, the magnetic field set up by coil 9 opposes the magnetic field of coil 8. Thus, the resultant magnetic pull when coil 9 is energized, is smaller than where coil 8 only is in operation. Thus when both coils 8 and 9 are energized, the spring 10 moves plunger 5 out of tube 6 and the throttle 2 is opened, increasing the speed of the engine and building up a higher voltage across the terminals of the generator 15 and 16. As this voltage builds up, a new balance between the combined magnetic fields of coils Sand 9 and the spring 10 will be established and the throttle 2 will come to rest in such a position that a higher operating speed of the engine will result, and consequently a higher voltage will be generated. Opening of switch 23 will cause coil 9 to lose its magnetic field and coil 8 will then act at full strength and the engine speed will be reduced to that occurring before the switch was closed.

Obviously changes may be made in the electrical connections and in the particular construction and arrangement of coils 8 and 9, their connections, and in the plungers and their connections, also in other parts without departing from the spirit of the invention, and such changes are contemplated.

Having thus fully described my invention, what I'claim is:-

1. An electric governor for controlling the speed of a prime mover arranged to drive an electric generator, said governor comprising a movable core, two electric coils arranged to act magnetically upon said movable core, and resistance means to resist movement of said core, one of said coils connected in shunt with the terminals of said generator, and the other of said coils having a shunt connection with an external circuit, upon closing of said external circuit and acting magnetically in opposition to the first of said coils, and control means for varying the speed of said prime mover and means for connecting said core and said control means.

2. The combination with a prime mover, an electric generator driven by said prime mover, an electric motor electrically connected to said generator to receive current therefrom, and a control device for said prime mover; of an electric governor comprising a solenoid having a longitudinally movable core and two coils, one within the other, encircling said core and arranged, one

to decrease the magnetic effect of the other upon said core, said coils being separately connected in shunt across said generator and said motor circuit, and means for operatively connecting said core and control device.

3. The combination with a gas engine having an intake manifold, a control valve in said manitold, an electric generator direct commuted to said engine to be driven thereby, an electric motor having an operating switch in the leads from said generator to said motor to supply current to said motor from said generator; of an electric governor comprising a solenoid having a movable core, and two concentric coils encircling said core, one of said coils being electrically connected in shunt across the terminals of said generator and the other of said coils being electrically connected in shunt across the leads to said motor and being energized by the closing of said switch, a spring to move said core in one direction, and means connecting said core and said control valve to operate said valve by the longitudinal movement of said core.

4. An electric governor for controlling the speed of a prime mover arranged to drive an electric generator, an electric motor connected to said generator to receive current therefrom, said governor comprising a movable core, two electric coils arranged to act magnetically upon said movable core, and resistance means to resist movement of said core, said coils being arranged, one to decrease the magnetic efiect of the other upon said core, said coils being separately connected in shunt across said generator and motor circuits, and control means for varying the speed of said prime mover and means for connecting said core and said control means.

' 5. An electric governor for controlling the speed of a prime mover arranged to drive an electric generator, said governor comprising a movable core, two electric coils arranged to act magnetically upon said movable core, and resistance means to resist movement of said core, one of said coils being connected in shunt with the terminals of said generator, and the other of said coils connected in shunt with an external circuit for energization through the closing of a manually operated switch in said external circuit and acting magnetically in opposition to the first of said coils, and control means for varying the speed of said prime mover, and means for connecting said core and said control means.

HAROLD D. GUMPPER.

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