Patent ID: 6188946
Filing Date: 2001-02-13
Classification: F16H,Y10T

Abstract:
A transmission control system for an automotive vehicle with a continuously variable automatic transmission whose speed ratio is defined as a ratio of transmission input to output speed and is changeable continuously depending on vehicle speed and engine load, comprising:a hydraulic actuator producing a regulated line pressure and a speed change control pressure necessary to adjust the speed ratio hydraulically; andan electronic transmission control unit including a data processing section that performs:(a) detecting an acceleration of a drive wheel of the vehicle;(b) detecting a vehicle speed;(c) controlling the transmission such that an upshifting action occurs by decreasing the speed ratio as the vehicle speed increases;(d) comparing the acceleration of the drive wheel to a predetermined acceleration value; and(e) inhibiting the upshifting action by preventing the speed ratio of the continuously variable transmission from being upshifted toward a speed ratio less than a predetermined upshift limiting threshold when the acceleration of the drive wheel is greater than the predetermined acceleration value.