Abstract: An intake system for a multiple-cylinder engine a plurality of primary discrete intake passages and a plurality of secondary discrete intake passages. Each pair of primary discrete intake passage and the secondary discrete intake passage communicate with one of the cylinders. Both the primary and secondary discrete intake passages are straight and the primary discrete intake passage is provided with a primary valve member which is provided with an opening and is selectively positioned in a closed position where the primary valve member limits the effective cross-sectional area of the primary discrete intake passage to the cross-sectional area of the opening and in an open position where the primary valve member wide opens the primary intake passage.

Abstract: An automatic transmission including a torque converter and a multiple stage transmission gear mechanism. A hydraulically actuated brake and a hydraulically actuated clutch is provided for alternate engagement to select alternately one of two adjacent gear stages. In order to prevent gear shift shock, the engaging of the clutch or the brake is controlled so that the engaging rate is faster for a predetermined time period in an initial period of a gear shifting operation than in a remainder period. A control circuit is provided to monitor the gear shifting operation and modifying the predetermined time period in accordance with the results of the latest gear shifting operation and store the modified value for the use in a next gear shifting operation.

Abstract: In a constant-speed cruising control system for a vehicle in which the throttle opening is feedback-controlled according to the difference between the actual vehicle speed and a desired vehicle speed so that the actual vehicle speed matches the desired vehicle speed, the vehicle speed is constantly detected when it increases in response to a driver's command, and the throttle valve is controlled so that the throttle opening converges on a target throttle opening which is predetermined according to the vehicle speed. The target throttle opening is corrected according to the running condition of the vehicle so that the vehicle speed is increased at a constant acceleration irrespective of the running condition of the vehicle.

Abstract: An engine output control system comprising an acceleration detector for detecting an amount of a stroke of accelerator and producing an acceleration signal in accordance with the amount of the stroke, throttle valve, electrical control mechanism for determining an electrical control signal to actuate the throttle valve in accordance with the electrical control signal, mechanical control mechanism mechanically linked with the throttle valve for actuating the same in accordance with the amount of the stroke, abnormality detector for detecting an abnormality of the electrical control mechanism, switch mechanism for producing a signal to switch a control for the throttle valve between the mechanical and the electrical control mechanism, and switching control mechanism for performing an actual switching action from the mechanical control mechanism to the electrical control mechanism based on the signal from the switching mechanism under a specific engine operating condition.

Abstract: In an automatic transmission control system, completion of gear-shifting is detected on the basis of both the rate of change in rotational speed of the output shaft of the torque converter and the rotational speed at which the output shaft of the torque converter is expected to rotate. That is, a rotational speed range within which the rotational speed of the output shaft of the torque converter is expected to fall upon completion of the gear-shifting is determined taking into account the rotational speed of the output shaft of the torque converter upon initiation of the gear-shifting and the gear ratio, and it is determined that the gear-shifting is completed when the rotational speed of the output shaft of the torque converter falls within the predetermined rotational speed range and the rate of change in rotational speed of the output shaft of the torque converter is reduced below a predetermined value.

Abstract: A vehicle automatic transmission having a torque converter and a multiple stage transmission gear mechanism connected with the torque converter. The gear stage of the gear mechanism is selected in accordance with the vehicle operating condition. The transmission includes friction members. One of the friction members is engaged for a higher gear stage and disengaged for a lower gear stage whereas the other is disengaged for the higher gear stage and engaged for the lower gear stage. In shifting down from the higher gear stage to the lower gear stage, the other friction member is engaged after a predetermined time from the disengagement of the one friction member.

Abstract: A lock-up control system for an automatic transmission including a torque converter coupled with an engine, a power transmitting gear arrangement controlled by a gear ratio control device in accordance with a shifting up or down signal, and a lock-up clutch provided for locking up the output shaft of the torque converter to the output shaft of the engine. The lock-up control system comprises lock-up operation control apparatus causing the lock-up clutch to be in its inoperative state when the gear ratio control device performs the control with the shifting up or down signal, and lock-up command device for preventing the lock-up operation control apparatus from causing the lock-up clutch to be in its inoperative state until a predetermined reductive variation in the speed of the output shaft of the torque converter arises after the shifting up signal is supplied to the gear ratio control device under the condition in which the lock-up clutch is in operation.

Abstract: A vehicle automatic transmission including a torque converter, a multiple stage transmission gear mechanism connected with the torque converter and a hydraulic control circuit for automatically selecting one of gear stages of the transmission gear mechanism. The hydraulic control circuit includes a kickdown control device which functions to shift down the gear mechanism when the engine control foot pedal is substantially fully depressed. Depending on the vehicle running condition, the kickdown control device shifts down the gear mechanism by two gear stages. The hydraulic circuit includes control circuit which functions to shift down the gear mechanism at first by one gear stage and then by a further one stage in sequence when a two stage shift down is required.

Abstract: A vehicle automatic transmission including a torque converter, a multiple stage transmission gear mechanism connected with the torque converter and a hydraulic control circuit for automatically selecting one of gear stages of the transmission gear mechanism. The hydraulic control circuit includes a kickdown control device which functions to shift down the gear mechanism when the engine control foot pedal is substantially fully depressed. Depending on the vehicle running condition, the kickdown control device shifts down the gear mechanism by two gear stages. The hydraulic circuit includes control circuit which functions to shift down the gear mechanism at first by one gear stage and then by a further one stage after a certain time delay when a two stage shift down is required.