Patent ID: 6345226
Filing Date: 2002-02-05
Classification: B60T,B60W,F16H,Y10T

Abstract:
A speed ratio control device used with a vehicle comprising a continuously variable transmission and a slip control system for suppressing a slip of a drive wheel by controlling either of braking force and drive force, comprising:a sensor which detects a vehicle speed, an actuator which varies a speed ratio of the transmission, and a microprocessor programmed to: estimate a vehicle speed based on a running state, compute a target speed ratio of the transmission based on the sensor detected vehicle speed when the slip control system is not operating, compute the target speed ratio of the transmission based on the estimated vehicle speed when the slip control system is operating, control the actuator so that the speed ratio of the transmission approaches the target speed ratio, determine whether the estimated vehicle speed is abnormal, and prohibit use of the estimated vehicle speed in speed ratio control when it is determined that the estimated vehicle speed is abnormal.