Patent ID: 9709159
Date: 2017-07-18
CPC Classifications: B60K,B60W,B60Y,F16D,F16H,Y02T,Y10S

Claim:
1. A method for controlling torque transfer of a friction-type shift element, the friction-type shift element closable by a closing pressure acting on a piston, a control valve is configured to control the closing pressure depending on a control signal of a control unit, the control valve is also configured to transmit or reduce a system pressure of a hydraulic circuit to the piston through setting of a valve lift, the valve lift of the control valve variable between fully open and fully closed depending upon the control signal of the control unit such that the closing pressure acting on the piston provides a target transmission torque of the friction-type shift element, the method comprising: controlling the closing pressure with the control valve upon presence of a closing request for the friction-type shift element and when a prevailing system pressure of the hydraulic circuit is above a threshold value for the system pressure, the closing pressure controlled with the control valve at least temporarily in a manner that is different than upon the presence of the closing request for the friction-type shift element and when the prevailing system pressure is below the threshold value for the system pressure.