Speed control apparatus for motorcar engine

Claim 1

Speed control apparatus for an internal combustion engine which drives a vehicle, the vehicle having a brake, said apparatus comprising an electric motor, an engine throttle valve, means coupling the motor and throttle valve such that when the engine speed reaches an upper limit or a lower limit of a pre-set speed, the electric motor is operated in normal or reverse direction for controlling the throttle valve to move respectively in closing direction or opening direction to maintain the pre-set speed, the latter means including a clutch means between the motor and throttle valve, a source of electrical energy, upper and lower limit detecting circuits between the source and motor to selectively energize the motor in a particular direction to maintain the engine speed within the pre-set range, and speed selection means between said source and motor and connected to said detecting circuits, said speed selection means including an idle speed selector, at least one cruising speed selector and corresponding voltage adjustment means operated by said selectors for regulating the voltage supplied to said motor, means automatically activating the voltage adjustment means associated with the idle speed selector when the cruising speed selector is inactived, and means for disconnecting the voltage adjustment means associated with the cruising speed selector from the motor supply circuit and setting the voltage adjustment means associated with the idle speed selector while also decoupling the clutch means when the brake pedal is operated, said throttle valve thereafter returning to its idle position under the control of the motor as determined by the voltage adjustment means associated with the idle speed selector when the brake pedal is released.