Patent ID: 6988976
Filing Date: 2006-01-24
Classification: F16H,Y10T

Abstract:
1. In a powertrain of an accelerating motor vehicle having an engine, a secondary power source, and a step-change automatic transmission for driving a load, a method for controlling an upshift of the transmission from a current gear to a next gear, the method comprising the steps of: establishing first shift points of a demanded engine output and a corresponding vehicle speed, at which the upshift would occur if the engine were the only power source; determining the length of a first period in which energy is available to the secondary power source; determining the length of a second period for the current vehicle speed to increase to a target vehicle speed of a first shift point whose corresponding demanded engine output is equal to a combined current demanded output of the engine and secondary power source; comparing the lengths of the first period and second period; and producing the upshift if the length of the second period is equal to or greater than the length of the first period.