VARIABLE SPEED CONTROLLER OF AUTOMATIC TRANSMISSION

摘要

When two friction engagement elements are disconnected and connected and are down-shifted to a variable speed stage two or more stages apart via an intermediate stage, after releasing first and second variable speed release elements,a variable speed control means performs control to form a low speed stage by engaging the first variable speed engagement elements, and then engaging the second variable seeped engagement elements while torque capacity of the second variable speed release element is feedback-controlled. Thus, by releasing the first and second variable speed release elements prior to the engagement of the first variable speed engagement element, input rotation can be quickly hopped up with maximum performance of an engine to which an automatic transmission is connected, and the speed shift time can be shortened. Further, by feedback-controlling torque capacity of the second variable speed release element after engagement of the first variable speed engagement element, torque fluctuation in the intermediate stage is alleviated and occurrence of unpleasant speed change shock can be avoided.