Abstract: A pressure regulating valve regulates an original pressure outputted from a manual valve by means of a control pressure generated by a solenoid in a D range and supplies the regulated original pressure to an engaging element. An electronic control unit filters a current signal supplied to the solenoid to generate the control pressure by using a strong filter when a N range is switched to a D range during stoppage of a vehicle so that the control pressure has a gentle rise characteristic, switches the filtering process to a filtering process using a weak filter to rapidly move the pressure regulating valve in a working pressure discharge direction when the N range is switched to the D range during running of the vehicle and returns the filtering process to the filtering process using a strong filter after a predetermined time period. Thereby, occurrence of shock is suppressed when the D range is again selected after the N range is selected during running in the D range.

Abstract: A shift control system for an automatic transmission having an automatic shift mode in which a proper gear ratio is automatically selected according to a shift command based on a throttle valve opening and a vehicle speed, and further having a manual shift mode in which a gear ratio is selected according to a shift command given by driver's manual operation. The shift control system includes timer means for counting an elapsed time after a shift operation has been started. The elapsed time is compared with a predetermined first re-shift permission time in the case of automatic shift operation and with a predetermined second re-shift permission time in the case of manual shift operation. The first re-shift permission time and the second re-shift permission time are different from each other to optimize the shift control both in the automatic shift mode and in the manual shift mode.

Abstract: A standby phase target time is determined with reference to a table according to a read engine load and vehicle speed. A standby phase real time is then measured, and a learning correction value is calculated and stored. In a next shifting operation, a value that is found by adding the learning correction value to a hydraulic pressure command value in the previous shifting operation is used as a new hydraulic pressure command value. This learning correction is performed in small regions where the vehicle speed increases with the throttle opening being substantially constant. This accurately compensates a change in characteristics of a hydraulic system without being affected by a rapid change in torque or the like.

Abstract: A pressure regulating valve regulates an original pressure outputted from a manual valve by means of a control pressure generated by a solenoid in a D range and supplies the regulated original pressure to an engaging element. An electronic control unit filters a current signal supplied to the solenoid to generate the control pressure by using a strong filter when a N range is switched to a D range during stoppage of a vehicle so that the control pressure has a gentle rise characteristic, switches the filtering process to a filtering process using a weak filter to rapidly move the pressure regulating valve in a working pressure discharge direction when the N range is switched to the D range during running of the vehicle and returns the filtering process to the filtering process using a strong filter after a predetermined time period. Thereby, occurrence of shock is suppressed when the D range is again selected after the N range is selected during running in the D range.

Abstract: A lockup control system for a torque converter of a vehicle equipped with an air conditioner. The lockup control system maintains a coasting slip restricted state of the torque converter even during coasting of the vehicle with an accelerator pedal released, for restricting slip rotation between input and output elements of the torque converter. The coasting slip restricted state is achieved by a coasting lockup capacity that is lower than a lockup capacity of the torque converter in a driving condition of the vehicle with the accelerator pedal depressed. According to the invention, the coasting lockup capacity is controlled according to an operation load of the air conditioner and increased as the operation load of the air conditioner increases.

Abstract: A shift control system for an automatic transmission having an automatic shift mode in which a proper gear ratio is automatically selected according to a shift command based on a throttle valve opening and a vehicle speed, and further having a manual shift mode in which a gear ratio is selected according to a shift command given by driver's manual operation. The shift control system includes timer means for counting an elapsed time after a shift operation has been started. The elapsed time is compared with a predetermined first re-shift permission time in the case of automatic shift operation and with a predetermined second re-shift permission time in the case of manual shift operation. The first re-shift permission time and the second re-shift permission time are different from each other to optimize the shift control both in the automatic shift mode and in the manual shift mode.

Abstract: A standby phase target time is determined with reference to a table according to a read engine load and vehicle speed. A standby phase real time is then measured, and a learning correction value is calculated and stored. In a next shifting operation, a value that is found by adding the learning correction value to a hydraulic pressure command value in the previous shifting operation is used as a new hydraulic pressure command value. This learning correction is performed in small regions where the vehicle speed increases with the throttle opening being substantially constant. This accurately compensates a change in characteristics of a hydraulic system without being affected by a rapid change in torque or the like.

Abstract: A band brake device used to apply a brake to a rotating drum forming part of an automatic transmission of an automotive vehicle. The band brake device comprises a brake band wrapped around the outer peripheral surface of the rotating drum. A lining material is bonded to the inner surface of the brake band to be contactable with the outer peripheral surface of the rotating drum. The brake band is provided at its movable end with a bracket which is adapted to be pushed by a piston of a hydraulic servo device. The bracket is connected through a link to a casing, so that the movable end is guided to be move in a direction generally parallel with a tangential direction of the outer peripheral surface of the drum at a position adjacent the movable end.

Abstract: A brake system comprising a brake drum having an outer peripheral surface, and a brake band including a flexible band-shaped metal member having fixed and actuation brackets mounted near the opposite ends thereof. The band-shaped metal member is wound around the outer peripheral surface of the brake drum with the fixed bracket being fixed to an anchorage pin. The brake band also includes a lining member fixed on the band-shaped metal member. An actuator is coupled to the actuation bracket for acting a force on the band-shaped metal member to bring the lining member into surface contact with the outer peripheral surface of the brake drum at a speed. Oil grooves are formed in the lining member for discharging oil from a space between the lining member and the brake drum to control the speed at which the lining member comes into surface contact with the brake drum. The oil grooves have an oil discharging capacity increasing as going from the fixed bracket toward the actuation bracket.