Patent ID: 6533702
Filing Date: 2003-03-18
Classification: F16H,Y10T

Abstract:
A shift control system of a hydraulic continuously variable transmission for an automotive vehicle having a hydraulic pressure control means for controlling with a hydraulic pressure the behavior of a rotating element and a speed feedback control means for setting a target speed of the rotating element on the basis of a speed of the vehicle and a load on the engine of the vehicle and feedback-controlling the hydraulic pressure control means so that an actual speed of the rotating element approaches the target speed, comprising:an actual hydraulic pressure detecting means for detecting an actual value of a hydraulic pressure acting on the rotating element; a target hydraulic pressure setting means for setting a target value of the hydraulic pressure acting on the rotating element; a pressure feedback control means for feedback-controlling the hydraulic pressure control means so that the actual hydraulic pressure detected by the actual hydraulic pressure detecting means approaches the target hydraulic pressure set by the target hydraulic pressure setting means; a stationary state detecting means for detecting whether the vehicle is in a substantially stationary state; and a control means for controlling the hydraulic pressure control means using speed feedback control executed by the speed feedback control means when it is detected by the stationary state detecting means that the vehicle is not in a substantially stationary state and controlling the hydraulic pressure control means using pressure feedback control executed by the pressure feedback control means when it is detected by the stationary state detecting means that the vehicle is in a substantially stationary state.