A HYDRAULIC CONTROL CIRCUIT FOR A CONTINUOUSLY VARIABLE TRANSMISSION

摘要

A hydraulic control circuit is disclosed for a continuously variable transmission having a continuously variable transmission unit ("variator") in which the position of at least one ratio determining element (e.g. A roller 28 of a toroidal race rolling traction type variator) is influenced by means of a hydraulic actuator (100, 100', 100"). The control circuit comprises a flow line (106) through which hydraulic fluid is fed to and from the actuator means (eg. A control valve 116 disposed in the flow line) for adjusting pressure in the flow line, and a first valve (125) connected to the flow line so that opening of the first valve diverts flow of fluid to/from the flow line.