| 摘要 |
PURPOSE:To prevent the mistaken learning with the oil temperature and to obtain the sufficient reducing effect of the shock caused by the speed change, by changing the target speed changing time in response to the hydraulic oil temperature of an automatic transmission. CONSTITUTION:In an automatic transmission, variable kinds of friction element is selectively and hydraulically actuated by the line pressure so as to select the prescribed speed and perform the motive power transmission. During the speed change, a line pressure learning control means learningly controls the line pressure so that the speed changing time becomes the target speed changing time, and prevents the shock caused by the speed change and while prevents the delay of the speed change. At this stage, a target speed changing time changing means changes said target speed changing time in response to the hydraulic oil temperature of an automatic transmission detected by an oil temperature sensor. Consequently, the target speed changing time is made to be appropriate at any hydraulic oil temperature of the transmission, and the learning control of the line pressure is accurately performed at any hydraulic oil temperature so that the preventing effect of the shock caused by the speed change can be securely attained. |
