| 摘要 |
PURPOSE:To enable slipping of a friction member to be prevented from occurring, by setting the hydraulic oil pressure regulating action of a line pressure regulating means as the same as at the lower speed step when the load of a engine increases while the higher speed step is kept fixed. CONSTITUTION:When the cut back zone, where the opening of a throttle valve 5 is larger than an opening corresponding to the car speed, is identified by the signal from a throttle sensor 202, a speed change gear mechanism 20 is fixed to 3rd speed step by a hold mode setting means 205. And further, when the increase of an engine load is detected by said throttle sensor 202 while 3rd high speed step is kept fixed, a control means 200 switches solenoid valves 71, 73 on and 72 off to make said speed change mechanism 20 select '3rd apostrophe' speed step to get a level of the line oil pressure sufficient to correspond to the engine load, thus preventing friction members from slipping. Due to the above construction, improvement of the durability of the friction members and stable high speed running state can be accomplished. |
