| 摘要 |
PURPOSE: A speed change control method of an automatic transmission for a vehicle is provided to minimize the shift shock and to improve transmission responsiveness by excluding second speed control when speed is automatically changed to a first speed from a third speed or manually changed to the L(Low) range. CONSTITUTION: At the D(Drive) range first speed at which a rear clutch and an end clutch(C2) are operated, shift control solenoid valve(S1,S2) are turned on to release the hydraulic pressure of a second speed, third speed and fourth speed pipelines(30,32,34). The hydraulic pressure supplied to the end clutch is released by a hydraulic distribution unit. A pressure control solenoid valve(SP1) is controlled at a high duty ratio, and the hydraulic pressure in the first speed pipeline is supplied to the rear clutch. When the hydraulic pressure of the end clutch is released, servo control by an accumulator(44) is performed.
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