| 摘要 |
PURPOSE:To shorten time required for speed change, and thereby restrain friction elements from generating heat by setting the engaging pressure of the friction elements high for the specified period of time at the time of speed change to the specified step of gear shifting and when oil temperature is equal to or more than a set one. CONSTITUTION:A control circuit 50 allows a judging means 51 to make judgement on speed change under a low engine load condition which causes engaging pressure to be lowered with engaging pressure controlled in response to basic engine load by a control means 54, when hydraulic pressure is supplied to the specified friction elements of a gear change mechanism so that the specified step of gear shifting is thereby actuated. In addition, when both oil temperature detected by an oil temperature detecting means 52 and the maximum temperature of the friction elements tend to be high, engaging pressure is set high for the specified period of time. Moreover, when vehicle speed detected by a vehicle speed judging means 53 is high, and when both time required for speed change and the heating value of the friction elements due to speed change are apt to be increased, engaging pressure is also set high for the specified period of time so that time required for speed change is thereby shortened. By this constitution, an increase in the temperature of the friction members can be restrained. |
