Motor generator with automatic speed and idling control

Claim 2

In combination with an electrical generator having an output, a load circuit connected with said generator output, said load circuit including a variable and intermittent load and an internal combustion engine driving said generator, load responsive means for automatically controlling the speed of said engine comprising fuel regulating means controlling the supply of fuel to said engine, governor means responsive to the speed of said engine and controlling said fuel regulating means to maintain the speed of said engine and generator normally at a selected value, electromagnetically operable means for overriding said governor means to maintain said fuel regulating means in condition to operate said engine at idling speed, and a control circuit comprising a resistor, means connecting said electromagnetically operable means in series with said resistor across the output of said generator, a silicon-controlled rectifier connected in shunt with said electromagnetically operable means, and means responsive respectively to load and noload conditions of said generator controlling said siliconcontrolled rectifier to render said silicon-controlled rectifier conductive to short and thereby deenergize said electromagnetically activated means when there is load on the generator, whereupon said fuel regulating means is controlled by said governor to maintAin said engine at said selected speed and to render said silicon-controlled rectifier nonconductive and thereby energize said electromagnetically operable means to override said governor and hold said fuel regulating means in idling condition when there is no load on the generator.

Claim 3

A combination according to claim 1, in which a capacitor is connected across said electromagnetically operable overriding means.

Claim 4

A combination according to claim 1, in which said generator is an alternating current generator and in which a diode is connected in series with said resistor and said electromagnetically operable overriding means.

Claim 5

A combination according to claim 1 in which said generator is an alternating current generator and said means for controlling the conduction of said silicon-controlled rectifier comprises a current transformer having a primary and a secondary, means connecting said primary in series with the generator load, rectifying means having an input and an output, means connecting the input of said rectifying means with the secondary of said transformer and means connecting the output of said rectifying means to said silicon-controlled rectifier to control the conduction of said silicon-controlled rectifier in accordance with current flowing through the primary of said transformer.

Claim 6

A combination according to claim 4, in which said generator has two load circuits and said current transformer has two primaries, one connected in series with one said load circuit and another connected in series with another said load circuit.

Claim 7

In combination with an alternating current generator having an output, a load circuit connected with said generator output, said load circuit including a variable and intermittent load, and an internal combustion engine driving said generator, means for automatically controlling the speed of said engine comprising fuel regulating means controlling the supply of fuel to said engine, governor means responsive to the speed of said engine and controlling said fuel regulating means to maintain the speed of said engine normally at a selected operating value, electromagnetic means for overriding said governor means to maintain said fuel regulating means in condition to operate said engine at idling speed, and a control circuit comprising a resistor and a rectifier, means connecting said electromagnetic means in series with said resistor and rectifier across the output of said generator, a current transformer having a primary and a secondary, means connecting said primary in series with said load, rectifying means having an input and an output, means connecting the input of said rectifying means with the secondary of said transformer, switching means connected in shunt with said electromagnetic means, and means connecting said switching means with the output of said rectifying means to actuate said switching means to short circuit and thereby deenergize said electromagnetic means when there is load on the generator, whereupon said fuel regulating means is controlled by said governor to maintain said engine at said selected speed, and to deactivate said switching means and thereby energize said electromagnetic means to override said governor and hold said fuel regulating means in idling condition when there is no load on the generator.

Claim 8

In combination with an alternating current generator having an output, a load circuit connected with said generator output, said load circuit including a variable and intermittent load, and an internal combustion engine driving said generator, means for automatically controlling the speed of said engine comprising fuel regulating means controlling the supply of fuel to said engine, governor means responsive to the speed of said engine and controlling said fuel regulating means to maintain the speed of said engine normally at a selected operating value, electromagnetic means for overriding said governor means to maintain said fuel regulating means in condition to operate said engine at idling speed, and a control circuit comprising a resistor and a rectifier, means connecting said electromagnetic means in series with said resistor and rectifier across the output of said generator, a current transformer having a primary and a secondary, means connecting said primary in series with said load, rectifying means having an input and an output, means connecting the input of said rectifying means with the secondary of said transformer, switching means connected in shunt with said electromagnetic means, and means connecting said switching means with the output of said rectifying means to actuate said switching means to short circuit and thereby deenergize said electromagnetic means when there is load on the generator, whereupon said fuel regulating means is controlled by said governor to maintain said engine at said selected speed, and to deactivate said switching means and thereby energize said electromagnetic means to override said governor and hold said fuel regulating means in idling condition when there is no load on the generator.

Claim 9

A combination according to claim 6, in which said generator has two load circuits and said current transformer has two primaries, one connected in series with one said load circuit and another connected in series with another said load circuit.

Claim 10

A combination according to claim 6, in which said switching means comprises a silicon-controlled rectifier.