Control device for transmission ratio for use in continuously variable vehicle gearbox has sensors for engine speed, input and output gearbox speeds plus microprocessor programmed to control transmission ratio of gearbox

摘要

A control device for the transmission ratio for use in a continuously variable vehicle gearbox has the gearbox transmitting an output torque of an engine to a driving wheel with an arbitrary transmission ratio. The device comprises: a sensor (68) to detect a speed of the engine; a sensor (64) to detect an input speed of the gearbox; a sensor (65) to detect an output speed of the gearbox; and a microprocessor which is programmed: to control the transmission ratio of the gearbox inside a certain range of the transmission ratio based on output signals of the sensors; to observe whether one of the sensors has an irregularity, based on the output signals of the sensors; and to correct the certain range of the transmission ratio so that it is narrower when an irregularity is established.