Patent ID: 6656086
Filing Date: 2003-12-02
Classification: F16H,Y10S,Y10T

Abstract:
A shift control method for an automatic transmission of a vehicle comprising:detecting atmospheric pressure; determining whether a predetermined atmospheric pressure applying condition is satisfied; and resetting values of shift control variables based on the detected atmospheric pressure when the predetermined atmospheric pressure applying condition is satisfied the shift control variables being variables for duty control of hydraulic pressure for friction elements of the automatic transmission, wherein the shift control variables of which the values are reset comprise at least one of: an initial release-duty (Dsr) for suddenly lowering a release duty for hydraulic pressure supplied to a release-element, a ramp-control slope (dDr) for gradually decreasing the release duty for the release-element from the initial release-duty (Dsr), and a high-holding duty (Dcr) for holding duty at a higher lever than a final duty of the ramp-control.