Patent ID: 8914201
Filing Date: 2014-12-16
Classification: F16H,Y10T

Abstract:
1. A control device for a belt type continuously variable transmission, comprising a primary pulley receiving an input from a drive source, a secondary pulley providing an output to a drive wheel, and a belt wound around the primary pulley and the secondary pulley so as to control a gear ratio determined by a running radius ratio of the belt on the pulleys by controlling a primary hydraulic pressure to the primary pulley and a secondary hydraulic pressure to the secondary pulley, the device further comprising: a belt slip control means for oscillating the secondary hydraulic pressure and monitoring a phase difference between an oscillation component included in an actual secondary hydraulic pressure and an oscillation component included in an actual gear ratio to estimate a belt slip condition, and controlling the actual secondary hydraulic pressure to decrease based on estimation of the belt slip condition so as to maintain a predetermined belt slip condition; and a belt slip control permission determining means for permitting the belt slip control means to perform a belt slip control when a torque change speed input to the belt type continuously variable transmission is less than a predetermined value at which a variation in the actual secondary hydraulic pressure and the oscillation component included in the actual secondary hydraulic pressure are separable.