Patent ID: 9689491
Date: 2017-06-27
CPC Classifications: F16H

Claim:
1. A controller for a vehicle power transmission system, the vehicle power transmission system including: a gear mechanism, a belt-type continuously variable transmission and a switching mechanism, the gear mechanism and the belt-type continuously variable transmission being provided in parallel with each other in power transmission paths between an input shaft and an output shaft, the belt-type continuously variable transmission including an input-side sheave and an output-side sheave, the switching mechanism being configured to selectively establish any one of a first transmission path of the power transmission paths and a second transmission path of the power transmission paths, the first transmission path being a path through which torque input from the input shaft is transmitted to the output shaft via the belt-type continuously variable transmission, the second transmission path being a path through which torque input from the input shaft is transmitted to the output shaft via the gear mechanism, the controller comprising: one or more processors programmed to a hydraulic pressure output device configured to control hydraulic pressure that is output to the input-side sheave based on the target speed ratio, wherein the one or more processors are further programmed to, when there is a failure in the hydraulic pressure output device, establish a state where torque is transmitted through the second transmission path, and determine whether the hydraulic pressure output device has returned to a normal state by comparing the target speed ratio and actual speed ratio of the belt-type continuously variable transmission with each other in the state where torque is transmitted through the second transmission path.