| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to estimate the revolving speed of one rotating element coupled by a friction clutch and to determine whether the friction clutch is completed with engagement.SOLUTION: An automatic transmission comprises: a plurality of planetary gear mechanisms; a plurality of engagement mechanisms including a friction clutch; means detecting an input revolving speed; means for detecting an output revolving speed; means detecting a hydraulic pressure supplied to the friction clutch; estimation means estimating a revolving speed of one rotating element coupled by the friction clutch; and determination means determining whether the friction clutch is completed with engagement on the basis of an estimation result of the estimation means. The estimation means estimates the revolving speed while assuming that a difference in the rotational energy of the automatic transmission between before and after unit time is equal to a work volume of the clutch. |
