Patent ID: 7744505

Claim:
A hydraulic fluid pressure control device comprising: a hydraulic pressure regulating section that selectively supplies hydraulic pressure to a clutch operatively disposed between an engine and a continuously variable transmission to selectively transmit torque from the engine to a primary pulley of the continuously variable transmission; a rotational movement detecting section that detects a rotational movement of the primary pulley when the hydraulic pressure acting on the clutch by the hydraulic pressure regulating section reaches a torque transmission point in which the clutch switches from an engaged state to a disengaged state such that the primary pulley stops rotating, and that outputs a signal during a change of the clutch from the engaged state to the disengaged state to indicate the torque transmission point; and a control section that estimates a clutch engagement hydraulic pressure at which the clutch is switched to the disengaged state when a vehicle is stopped and in a running range based on the hydraulic pressure acting on the clutch by the hydraulic pressure regulating section when the rotational movement detecting section initially detects the torque transmission point, the control section further controls the hydraulic pressure to change the clutch from the engaged state to the disengaged state when the vehicle is stopped and in the running range, so that the torque from the engine does not rotate a secondary pulley of the continuously variable transmission via a drive belt wrapped around the primary pulley and the secondary pulley.