| 摘要 |
<p>PURPOSE: To achieve smooth downshifts. CONSTITUTION: Off-going torque transmitting devices C1, C2, C4 are first partially released to permit an increase in the input speed of an automatic transmission, and at the same time on-coming torque transmitting devices C1, B1 are filled in preparation for engagement thereof. When the slip in the on-coming torque transmitting devices is near zero, the pressure of each on-coming torque transmitting device is progressively increased while the pressure of each off- going torque transmitting device is controlled to maintain the near-zero on-coming slip speed condition. When each on-coming torque transmitting device develops sufficient torque capacity, a tie-up state develops between the on-coming and off-going torque transmitting devices, and a drop in the acceleration of an output shaft 30 is detected to release the off-going torque transmitting devices. When the on-coming torque transmitting devices are fully engaged, the shift is complete.</p> |
