| 摘要 |
PROBLEM TO BE SOLVED: To eliminate a shift response delay at low temperature time of a direct-acting valve type automatic transmission by application of existing control logic without deteriorating a shift shock. SOLUTION: In a 3 to 4 up-shift performed by a release of a forward clutch by reduction in working pressure Po and fastening of a band brake by an increase in working pressure Pc as a result of transferring to inertia travel by reduction in throttle opening TVO, fastening side hydraulic fluid pressure Pc and releasing side hydraulic fluid pressure Po are transitionally controlled by an illustrated optimal time schedule according to actual input torque Ti at normal temperature time. At low temperature time when causing the shift response delay such as these hydraulic pressure Pc, Po delay more than the optimal time schedule, maximum input torque is set as the input torque Ti, and these hydraulic fluid pressur Pc, Po are returned so as to be transitionally controlled by the illustrated optimal time schedule for controlling the hydraulic fluid pressure Pc, Po in the same logic as the normal temperature time by using this torque, so that the shift response delay at low temperature time can be eliminated without deteriorating the shift shock.
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