Apparatus and method for controlling speed change of a vehicle automatic transmission

摘要

With a speed change control wherein a speed change step is determined corresponding to the gradient of a road surface on which a vehicle is travelling, an upshift requirement is output at the time of a downslope, based on the gradient being gentle, and a reference acceleration (SLDVSP) and a reference engine load (SLTVO) are set corresponding to vehicle speed (VSP), speed change step, and gradient. Then, only when an actual acceleration (DVSP) is greater than or equal to the reference acceleration, and an actual engine load (TVO) is greater than or equal to the reference engine load, is upshift executed based on the upshift requirement, and for other than the above conditions, the upshift requirement is cancelled.