Abstract: A torque detecting device includes a first rotary member connected to an input shaft and a second rotary member connected to an output shaft and arranged coaxially with the first rotary member. An elastic member is sandwiched between the first rotary member and the second rotary member and deforms according to the torque acting thereon. A sensor is arranged confronting the first and second rotary members to detect their rotational phases and a torque computer computes the torque by determining the rotational phase difference between the first and second rotary members from the rotational phases as detected by the sensor.

Abstract: An automatic transmission control system includes a frictional engagement element formed of alternating radially inner and outer thin plates for selectively transmitting a torque. The control system further includes a hydraulic servo having a piston which selectively engages/disengages the frictional engagement element responsive to an oil pressure. An electric characteristic detector detects (monitors) an electric characteristic which changes with change in the apply force of the frictional engagement element; and an apply force control unit controls the apply force of the frictional engagement element. The electric characteristic detector includes a signal generator for generating an electric signal in accordance with the relative positions of two electrically conductive members, which move as the frictional engagement element is engaged/disengaged.

Abstract: A shift control system for an automatic is designed to prevent engine racing and clutch tie-up during a clutch-to-clutch shift (clutch switching shift) involving engagement/disengagement of first and second frictional engagement elements. The shift control system includes an engagement force controller for independently controlling both of the frictional engagement elements. A gear ratio calculator continuously calculates a gear ratio r of the transmission and a shift characteristic value calculator calculates a shift characteristic value .alpha. based on changes in the gear ratio between the start of the shift and completion of the shift. A control value calculator calculates a control value .beta., based on the shift characteristic value .alpha. calculated by the shift characteristic value calculator and a shift characteristic value .alpha.I on an ideal gear ratio curve. The control value .beta. is calculated so that the shift characteristic value .alpha. coincides with the shift characteristic value .

Abstract: A shift control system of an automatic transmission controls operating forces on frictional engaging elements being engaged and disengaged with gear elements during a shift operation by generating a target transmission variable which prevents a rate of change of a corresponding target input rotational speed from inverting at the start of the shift operation and/or at the end of the shift operation. The target transmission variable may be the target input rotational speed, a target gear ratio, or other variable corresponding to a target input rotational speed which has a rate of change gradually changing at the start and end of the shift operation so as to avoid any inversion of the rate of change within a predetermined duration after the start of the shift operation and within a predetermined duration before the end of the shift operation.