Shift timing detecting system for automatic transmission

Abstract

A shift timing detecting system for detecting the start of a shift of an automatic transmission A in terms of a change in the R.P.M. of a predetermined rotary member after a shift command has been outputted. The shift timing detecting system comprises: a detector for detecting a change in the output R.P.M. of the automatic transmission; an arithmetic processor for arithmetically processing the change in the output R.P.M. with different coefficients to determine two processed values: a comparator for comparing the two processed values: and a shift start decider 5 for deciding the start of the shift on the basis of the result of the comparison. Since the shifting situation can be grasped from the change in the output torque accompanying the start of the shift and the change in the output R.P.M. caused by the former change, the start of the shift can be accurately detected without any time delay.

Dependencies are inferred from the claim text.