Patent ID: 9303762
Filing Date: 2016-04-05
CPC Classification: F16H

Claim Text:
1. A hydraulic pressure controller for a continuously variable transmission that changes hydraulic pressure supplied to each pulley of the continuously variable transmission to change a gear ratio, the hydraulic pressure controller comprising: an oil pump; a regulator valve that adjusts hydraulic pressure of hydraulic oil discharged from the oil pump and output as a line pressure by bifurcating the oil discharged from the oil pump; and a first and a second control valve each of which further adjusts the line pressure and outputs a control pressure as hydraulic pressure supplied to each of the pulleys of the continuously variable transmission; a hydraulic pressure circuitry configured to execute a hydraulic pressure controller feedback, wherein the hydraulic pressure controller feedback adjusts the line pressure in accordance with a level of the hydraulic pressure supplied to the pulleys, and after driving a valve body of each control valve in the valve opening direction, the hydraulic pressure circuitry executes oscillation suppression control that temporarily suppresses movement of the valve body, the control valve uses a driving hydraulic pressure input to the control valve to drive the valve body in the valve opening direction, and after the hydraulic pressure controller starts to drive the valve body in the valve opening direction, the oscillation suppression control further changes the driving hydraulic pressure to suppress movement of the valve body in a valve closing direction when the valve body oscillates as the output of the driving hydraulic pressure starts.