Bridging clutch for hydrodynamic torque converter has valve opened in depend ence on speed, temperature or viscosity

摘要

The bridging clutch which is mounted actively between an output member of the torque converter and the input member has an axially displaceable piston 136 which is provided on one side with an engagement chamber 124 for the bridging clutch and on the other side with a disengagement chamber 125. The bridging clutch has at least one valve 138 dependent on its speed and/or temperature and/or viscosity of the fluid, and this valve influences the pressure difference existing between the two chambers and also the engagement force of the bridging clutch. The valve can additionally or alternatively control a fluid stream between the two chambers, and in this case the valve is opened in a lower speed and/or temperature range and/or upper viscosity area and is closed in a second higher speed and/or temperature range and/or lower viscosity range. If speed responsive the valve preferably operates by centrifugal action. IMAGE