Patent attributes
An oil pressure control apparatus for an automatic transmission includes a calculating means for calculating, on the basis of a transmission output shaft rotational speed, at a time of a shift operation from a neutral shift stage to another shift stage appropriate to a vehicle driving condition, output-side rotational speeds of frictional engagement elements, and a shift stage selecting means for selecting a shift stage, in which oil with line pressure is supplied to a first frictional engagement element, from among the frictional engagement elements, and in which a minimum difference exists between the output-side rotational speed of the first frictional engagement element and an input-side rotational speed of a second frictional engagement element, from among the plural frictional engagement elements. The second frictional engagement element corresponds to the first frictional engagement element for the shift stage selected by the shift stage selecting means.
