Hydromechanical torque sensor for expanding pulley in vehicle power train

摘要

The hydromechanical torque sensor (14) has cam discs (18,19) with conforming cam faces between which are located spreading elements (20) to tend to move the cam faces apart under high torque to act in use on one half of the expanding pulley via first and second plenum chambers (22,23) connected to a source of hydraulic fluid under pressure. Supply to the chambers is via a throttle.The plenum chambers of the torque sensor can be connected to or sealed from each other as a consequence of change in the effective dia. of the pulley to change the ratio of a transmission including the pulley. The connection between the chambers may be allowed by one-way action of a lip seal (67) or by a valve.