Road and engine speed governor with linear actuator

Abstract

A governor is disclosed for governing engine and load speed and which is especially adapted for use with motor vehicles. It comprises an overriding throttle closing device with a linear actuator for moving the device to a position for limiting the engine speed and load speed to governed values. An electronic control circuit comprising a microprocessor operating under program control produces motor control signals for a reversible electric motor which drives the actuator means through a gear train and lead screw. An engine speed signal generator provides an electrical speed signal to the control circuit and a road speed signal generator supplies a load speed signal to the control circuit. When the speed signal exceeds a predetermined value, the control circuit produces motor control signals for operating the motor at full speed to move the actuator to a reference position causing operation in a reference point governing mode. In this mode when the speed signal exceeds the governed value, the control circuit produces motor control circuits for operation of the motor at slow speed in the close throttle direction. When the speed signal is less than the governed speed, the control circuit produces motor control signals for operating the motor at slow speed in the wide open throttle direction. The slow speed of operation is adapted to provide smooth governing action with small overshoot and minimal droop.