Abstract: The power train of a motor vehicle has an electronic unit which controls the condition of an automated clutch between the engine and a manually shiftable transmission. The control unit has a normal or standard operating mode when the various sensors which are connected with and transmit signals to the control unit (as well as the signal transmitting connections such as buses and/or cables) are not defective, and a standby or emergency mode when one or more sensors and/or connections are (temporarily or irreversibly) defective. The control unit then prevents the clutch from permitting or causing a creeping or crawling movement of the vehicle while the engine is idling and the transmission is shifted in a gear other than neutral. The mode of operation of the control unit can be changed back to normal in response to termination of a faulty operation of one or more sensors and/or connections, for example, with a predetermined delay.

Abstract: A target engine torque Tem and a target pump torque TPm are calculated based on a target speed ratio em set in accordance with the operational state of a vehicle, and a target lockup torque TLCm is calculated by subtracting the target pump torque TPm from the target engine torque Tem. Using, as a feed-forward term, a basic linear solenoid output pressure Qbase for generating the target lockup torque TLCm in a lockup clutch, a feed-back term calculated based on a deviation de between the actual speed ratio e and the target speed ratio em is added to the basic linear solenoid output pressure Qbase, and the engage force of the lockup clutch is controlled by the resulting linear solenoid output pressure Qout. Thus, the actual speed ratio of the torque converter quickly and accurately follows the target speed ratio set in accordance with the operational state of the vehicle.

Abstract: A clutch control system for the automatic control of a motor vehicle clutch (14) which connects an engine (10) with a gearbox (12) under the control of a driver-operated gear ratio selector lever (24). The control system includes an electronic control unit (36) which controls initial clutch. take-up on starting of the vehicle, clutch re-engagement following each ratio change, disengagement on movement of the gear selector lever (24) to change the operative ratio of the gearbox (12), and clutch disengagement on the coming to rest of the vehicle. The level of clutch engagement is controlled in response to an engine speed error signal (E) derived from a comparison of current engine speed (Ve) and a reference speed signal (Vr) generated by the control unit, the error signal being compared with a current clutch position signal (Vc) to produce a clutch actuation signal (Vce).

Abstract: The present invention relates to a method and an apparatus for controlling a car equipped with an automatic transmission having a lockup clutch. According to the control method of the present invention, when the lockup clutch is in the lockup state, a variation of a generated torque is detected. When the range of the torque variation detected exceeds a predetermined value, an engine torque is reduced by controlling the engine, and the automatic transmission is controlled to compensate for a reduction of the driving torque due to a reduction of the engine torque. Thus, the speed change ratio is changed to the low gear side.

Abstract: In the fuel cut state during deceleration, an actual vehicle speed Vs is compared with a target vehicle speed Vso when the direct coupling state is changed into a semi-coupling state, or otherwise an actual engine rotational speed Ne is compared with a return engine rotational speed Neo at the return from fuel cut. Then, if Vs.ltoreq.Vso or Ne.ltoreq.Neo+K (K is a positive predetermined value), the clutch is changed from the direct coupling state into the semi-coupling state. Thus, shock due to torque change at the time of return from fuel cut can be reduced, and during the coast down, the fuel cut state can be maintained until the low rotational speed is attained. Both improvement of fuel economy and efficient use of engine brake can be attained. Engine stall can be prevented at the time of abrupt braking.

Abstract: The invention is directed to a method and an arrangement for controlling the output power of a drive unit of a motor vehicle wherein a desired output torque command is determined on the basis of the driver command. A desired engine torque is computed from this desired output torque command while considering the torque transmission of a converter unit of an automatic transmission in all steady-state operating states. The converter unit is equipped with a controllable clutch. The desired engine torque is prepared by adjusting the output parameters of the engine.

Abstract: A method of diagnosing a lock-up mechanism for a torque converter in an automatic transmission of an automotive vehicle includes the steps of sensing vehicle speed and engine speed, calculating a vehicle speed to engine speed ratio based on the sensed vehicle speed and engine speed, knowing when the torque converter transitions between unlock and lock are initiated, determining whether the calculated ratio is greater than a predetermined threshold when the torque converter transitions between unlock and lock, and concluding that a failure of the lock-up mechanism has occurred if the calculated ratio is not greater than the predetermined threshold within a predetermined time since transition of the torque converter.

Abstract: A method and an apparatus for controlling a car equipped with an automatic transmission having a lockup clutch. According to the control method when the lockup clutch is in the lockup state, a variation of a generated torque is detected. When the range of the torque variation detected exceeds a predetermined value, an engine torque is reduced by controlling the engine, and the automatic transmission is controlled to compensate for a reduction of the driving torque due to a reduction of the engine torque. Thus, the speed change ratio is changed to the low gear side.

Abstract: A supercharger control system for use with an automatic transmission connected to an internal combustion engine and having its gear stages set according to a throttle opening or its corresponding data and an engine R.P.M. or its corresponding data. The range for turning ON the supercharger of the engine is set for each of the gear stages on the basis of the throttle opening or its corresponding data and further to a higher throttle opening side in accordance with the increase in the engine R.P.M. A hysteresis is set such that the range for switching the supercharger from OFF to ON is shifted to a higher throttle opening side than the range for switching the same from ON to OFF. The changing width of the ON-to-OFF range to the higher throttle opening side in accordance with the increase in the engine R.P.M. is set smaller than the hysteresis width within a predetermined gear stage range.

Abstract: In a powertrain including an engine controlled by engine manifold conditions, a hydrodynamic torque converter having a bypass clutch, multiple ratio automatic transmission connected to the drive wheels of the vehicle, a solenoid-operated hydraulic valve, supplying pressurized fluid to engage and release the bypass clutch, is controlled by operation of a feedforward control system. An engine math model produces a signal representing predicted torque output by the engine, which signal is applied as input to an inverse mathematical model of the solenoid-operated valve that supplies hydraulic fluid to the bypass clutch.

Abstract: In order to prevent occurrence of engine stall even when a quick braking is made in a state where a torque converter of an automatic transmission is locked up, the torque converter is locked up in accordance with a throttle opening degree and a vehicle speed, and the lock-up is released at least when the braking operation is carried out. The opening degree B of an idle speed control valve (ISCV) for bypassing a throttle valve simultaneously with the lock-up is set, and the opening degree B is set as an actual control opening degree IV of ISCV when the opening degree B is larger than the opening degree IAV of ISCV which is set in accordance with the load of an engine. When the release of the lock-up is started, the actual control opening degree IV is gradually reduced to the opening degree IAV by a prescribed attenuation amount K. As a result, the engine stall due to a response delay to the release of the lock-up clutch can be prevented.

Abstract: A hydraulic control for an automatically shifted power transmission has an electronically controlled governor pressure source which provides a speed and throttle sensitive pressure for controlling the shift points and trim boost in the transmission control. An inhibitor circuit is activated in the event of a discontinuance of the electrical control, resulting in maximum governor pressure, to permit selected vehicle operation in one forward ratio and a reverse ratio. Each ratio interchange is controlled by a respective shift valve and clutch control valve. Each clutch control valve has an integral trim control which is effective to control the pressure rise in the on-coming clutch without bypassing fluid to an exhaust. Also during a ratio interchange, an off-going clutch is controlled at a reduced pressure during a portion of the ratio interchange.

Abstract: A system for controlling the transient torque output of a multicylinder, variable displacement, spark-ignited, fuel injected automotive internal combustion engine during periods when the effective displacement of the engine is being changed includes a spark timing controller, a throttle controller for positioning an intake air throttle, an engine cylinder operator for deactivating and reactivating at least some of the engine's cylinders, and an engine controller having a processor for selecting the number of cylinders for operation and for operating the spark timing controller, the throttle controller, and the cylinder operator so that during any transition from operation with a first number of activated cylinders to operation with a second number of activated cylinders, the processor will alter the spark advance and control the amount of air entering the engine cylinders so that the torque output of the engine will remain relatively unchanged during the transition.