摘要:
A control system for an automatic transmission that does not require a cut-off valve, and that can inhibit a reverse control even if a detection unit for detecting a shift range fails. The control system includes a first friction engagement element, which is engaged in predetermined forward and reverse shift speeds, a detection unit that detects a shift range from shift ranges that include a forward range and a reverse range; a failure judgment unit for judging failure of the detection unit, and an avoidance unit for shifting to a forward shift speed that does not engage the first friction engagement element if the failure judgment unit determines that the detection unit has failed.
摘要:
A control apparatus for an automatic transmission including an automatic speed change mechanism that has an input shaft connected to a drive source, an output shaft connected to driving wheels, and a plurality of friction engagement elements, and that performs a shifting operation among a plurality of shift speeds by changing engagement/disengagement states of the plurality of friction engagement elements.
摘要:
A control system for an automatic transmission that does not require a cut-off valve, and that can inhibit a reverse control even if a detection unit for detecting a shift range fails. The control system includes a first friction engagement element, which is engaged in predetermined forward and reverse shift speeds, a detection unit that detects a shift range from shift ranges that include a forward range and a reverse range; a failure judgment unit for judging failure of the detection unit, and an avoidance unit for shifting to a forward shift speed that does not engage the first friction engagement element if the failure judgment unit determines that the detection unit has failed.
摘要:
A lock-up control apparatus for an automatic transmission in which operations of four engagement elements are required when shifting is performed from a first shift speed to a second shift speed, the first shift speed being achieved by engagement of a first engagement element and a second engagement element, the second shift speed being achieved by engagement of a third engagement element and a fourth engagement element. The lock-up control apparatus includes a lock-up control unit that performs a control for bringing a lock-up clutch into one of a disengagement state and a slip state at a start of shifting, and that prevents reengagement of the lock-up clutch at a completion of engagement of the third engagement element when shifting is performed from the first shift speed to the second shift speed during lock up.
摘要:
In an operation of controlling an automatic transmission, an engagement pressure for each hydraulic servo in a normal operation is determined so that none of friction engagement elements slips at each shift speed in the normal operation, and so that in case of a failure in which the friction engagement element that is supposed to be disengaged in the normal operation is engaged, one of the friction engagement elements slips, and thus one of the shift speeds is established. In the control operation, upon detection of a failure state in which a gear ratio after a shift operation is a gear ratio of a shift speed different from a shift speed to be established, the slipping friction engagement element is disengaged, and the shift speed that is different from the shift speed to be established is temporarily retained.
摘要:
In an operation of controlling an automatic transmission, an engagement pressure for each hydraulic servo in a normal operation is determined so that none of friction engagement elements slips at each shift speed in the normal operation, and so that in case of a failure in which the friction engagement element that is supposed to be disengaged in the normal operation is engaged, one of the friction engagement elements slips, and thus one of the shift speeds is established. In the control operation, upon detection of a failure state in which a gear ratio after a shift operation is a gear ratio of a shift speed different from a shift speed to be established, the slipping friction engagement element is disengaged, and the shift speed that is different from the shift speed to be established is temporarily retained.