Shift control method and system of automatic transmission

Abstract

A shift control method of an automatic transmission controls a skip shift from a first shift-speed achieved by engagements of first and second frictional elements to a second shift-speed achieved by engagements of third and fourth frictional elements, wherein the engagements of the third and fourth frictional elements is controlled after completion of releases of the first and second frictional elements.

Description

[0001] Cross References to Related Applications [0002] This application claims priority from Korean Patent Application No. 10-2008-0120051 filed on Nov. 28, 2008, the entire contents of which are hereby incorporated for all purposes. technical field [0003] The invention relates to a shift control method and a shift control system of an automatic transmission. In particular, the present invention relates to a shift control method and a shift control system of an automatic transmission, which control shifting from an N speed obtained through engagement of first and second friction elements to shifting through third and fourth friction elements Engage to get the N-3 gear speed. Background technique [0004] Generally, one friction element is released and the other friction element is engaged according to clutch-to-clutch shift control. However, during certain skip shifts, two friction elements may be released while two other friction elements may be engaged. [0005] In ...

AI Technical Summary

Problems solved by technology

[0010] However, according to this shift control method, since the shift from the 6th gear speed to the 3rd gear speed is performed through the intermediate gear speed, the output torque of the intermediate gear speed may be generated, and a double shifting feeling may be felt

In addition, shift vibration may occur

Images