Abstract: A method for controlling a vehicle having a first clutch mounted between an engine and a gear drive transmission, and dog clutch type torque transmission means disposed between an input shaft and an output shaft of the gear drive transmission, and wherein the first clutch is controlled at starting the vehicle or at gear shifting, comprising the steps of controlling a transmission torque of the first clutch based on a difference between the engine speed/revolution speed of the input shaft at starting the vehicle so as to control a quantity of increase in a transmission torque of the first clutch in accordance with the value of the difference; and controlling the engine torque based on the transmission torque of the first clutch so as to increase the engine torque according to an increase in the transmission torque of the first clutch.

Abstract: The invention is directed to a method for controlling the operation of a clutch (19) which coacts with an automatic transmission stage (17). A variator controller (16) is assigned to the automatic transmission stage (17) and a contact-force control (18) is assigned to the clutch (19). Depending upon the detected and classifiable drive situations, first and second torque/contact-force reserves (13, 44) are determined which are supplied to an input quantity ME (22) of the variator controller (16) and to the contact-force control (18) for the clutch (19). The output signals (20, 21) of the variator controller (16) and the contact-force control (18) influence the operation of the automatic transmission stage (17) and the clutch (19).

Abstract: A vehicle clutch control system that can prevent an engine (222) from racing when a friction clutch (304) is disengaged and engaged. When a driver stamps an accelerator pedal (206) over a predetermined depth at the time of completion of transmission gear speed change, clutch engagement is prohibited if a clutch rotation speed is slower than a prescribed speed, or an accelerator is maintained to a 0% opening position.

Abstract: A system and method of controlling an automatic clutch to prevent a motor vehicle engine from stalling is disclosed. The method includes the steps of determining an engine stall threshold, detecting accelerator pedal actuation, detecting current engine speed, and comparing current engine speed to the engine stall threshold. If the engine speed is below the engine stall threshold, a controller detects and compares vehicle acceleration to predetermined threshold acceleration such that the automatic clutch is actuated only when the vehicle acceleration is below the threshold acceleration. The system includes the step of detecting foot brake position such that the automatic clutch is only actuated if the foot brake is properly actuated. The controller will then actuate the automatic clutch to proportionally decouple the engine from the transmission to prevent engine stall. The automatic clutch will remain open until detecting a predetermined clearing condition.

Abstract: In a method and apparatus for diagnosing a malfunction in a clutch actuator of a motor vehicle, the actual position of the clutch actuator is measured by a position sensor. Simultaneously, an estimated position of the clutch actuator is calculated by an emulation unit that emulates the function of the clutch actuator. Malfunctions of the clutch-actuator are diagnosed by comparing the actual, measured position to the estimated position.

Abstract: In a power transmission, which adjusts and transmits the rotational output of an engine by the engagement control of a starting clutch 5, the rotational speed Ne and the suction negative pressure Pb of the engine are measured while the starting clutch is being actuated from a disengaged condition to an engaged condition with the engine being operated under a constant operational condition. An engagement-control value is calculated for the starting clutch when there is a change in the rotational speed and the suction negative pressure being measured, and the engagement-control value calculated is stored as an initial control value for starting an engaging action of the starting clutch. This initial control value is used for controlling the engagement of the starting clutch.

Abstract: A control system/method for controlling a vehicle drivetrain (10) including an engine (18), a transmission (12) and, a centrifugal clutch (20) for drivingly coupling the engine output (136) to the transmission input shaft (28) during vehicle launch. A system controller (50) issues command output signals (56) for controlling engine speed (ES) on a closed loop basis.

Abstract: A correction coefficient setting unit calculates as a difference in an actual revolution speed the difference between the actual revolution speed of a front driving axle and the actual revolution speed of a rear driving axle. Moreover, the correction coefficient setting unit calculates the ideal reference revolution speed of the front driving axle and the ideal reference revolution speed of the rear driving axle in consideration of a difference in a radius of gyration between the driving axles. The correction coefficient setting unit also calculates as a difference in a reference revolution speed the difference between the ideal reference revolution speed of the front driving axle and the ideal reference revolution speed of the rear driving axle.

Abstract: In a method and apparatus for diagnosing a malfunction in a clutch actuator of a motor vehicle, the actual position of the clutch actuator is measured by a position sensor. Simultaneously, an estimated position of the clutch actuator is calculated by an emulation unit that emulates the function of the clutch actuator. Malfunctions of the clutch-actuator are diagnosed by comparing the actual, measured position to the estimated position.

Abstract: The invention relates to an urban driving operating method for an electronically controlled automatic transmission in which a driving speed characteristic (vf) is determined and it is possible to recognize an urban driving state when the driving speed characteristic (vf) is within a presettable value range with an upper limit and in which in addition a driving activity characteristic (FCOUNTER) is continuously determined. It is proposed according to the invention that the urban driving state be recognized when the driving activity characteristic (FCOUNTER) is also within a presettable value range with an upper limit and that a drive program optimized for the urban driving state be accessed.

Abstract: A transmission system for a straddle vehicle which provides two operating modes, namely semi-automatic and automatic. With the semi-automatic transmission system, an operator only uses a switching means mounted on a sheeting bar of the vehicle for activating a clutch actuator and a shift actuator. The clutch actuator disengages a transmission clutch while the shift actuator operates a shifter for changing the transmission ratio. With the automatic transmission system, an Electronic Control Unit reads inputs signals such as speed of the engine (RPM), speed of the vehicle, opening of a throttle valve and position of a shifter and accomplishes a smooth shifting by activating a clutch actuator, a shift actuator and a modulated controlling valve.

Abstract: A transfer case control system or apparatus 10 is provided for use on a four-wheel drive vehicle of the type having a transfer case 32, a front driveshaft 22 and a rear driveshaft 26. Transfer case control system 10 includes a conventional microcontroller or controller 40 having a memory unit 42 and operating under stored program control. Controller 40 is communicatively coupled to sensors 44, 46, 48, and to transfer case 32. Controller 40 selectively transmits a torque control or “boost torque” signal to transfer case 32, based upon the rate of change of the vehicle's throttle position and the speed of driveshafts 22, 26.

Abstract: In a method for controlling a drive line of a vehicle, in which a power-shift clutch is engaged for torque transmission while driving, the point of engagement of a power-shift clutch that is disengaged in parallel is determined by a nonsteady-state engagement operation.

Abstract: A damper clutch control method comprising the steps of detecting a throttle opening, an engine rpm and an turbine rpm; performing lift-foot-up shifting if throttle opening is abruptly decreased; determining if a difference in engine rpm and turbine rpm is below a predetermined value; and duty controlling a damper clutch if the difference in engine rpm and turbine rpm is below the predetermined value.

Abstract: A gear-mesh type automatic transmission system capable of controlling clutch coupling speed so as to mitigate shock likely to occur upon changeover of speed stage regardless of not only time-dependent deterioration of an electromagnetic clutch but also dispersion among individual clutches. The gear-mesh type automatic transmission system includes an electromagnetic clutch (2) for effectuating transmission and interruption of output power from an output shaft (21) of an engine (1) to an input shaft (22) of a gear-mesh type transmission (3), a shift/select actuator (5) for shifting a speed change gear to a shift/select position in the gear-mesh type transmission (3), a shift/select position sensor (6) for detecting a shift/select position of the speed change gear, and a control unit (4) for driving the shift/select actuator (5) in accordance with a shift lever position selected by a driver, to thereby change over automatically the gear-mesh type transmission (3) to a target speed stage.

Abstract: A method of controlling a dual clutch transmission of a motor vehicle, wherein the first clutch acts to transmit torque to the first driven gear, and the second clutch acts to transmit torque to the second driven gear. The steps involved in controlling the transmission include determining a predetermined first clutch slip value based on the perceived vehicle loading, initiating launch of the motor vehicle with both the first and the second clutch partially engaged, determining the vehicle inertia value based on the summation of instantaneous vehicle inertia values during vehicle launch, and controlling either the first or the second clutch to disengage when the predetermined first clutch slip value is reached.

Abstract: An automatic clutch control method and system includes steps for controlling a vehicle master clutch to prevent the clutch from destructively overheating due to excessive slipping. A heat buildup value is determined from various engine operating parameters, such as output torque, engine speed, and input shaft speed. The heat buildup value can be increased or decreased depending on the various engine operating parameters. A signal generating device is responsive to the heat buildup value exceeding a first predetermined heat buildup limit to generate a clutch protection output signal effective to cause the clutch to be operated in an aggressive mode of operation to fully engage the clutch at a faster rate. The signal generating device is also response to the heat build value exceeding a second predetermined heat buildup limit and slow vehicle speed to generate a clutch protection output signal effective to cause the clutch to be operated in a fully disengaged mode of operation.

Abstract: A control device for controlling a clutch of a vehicle wherein an actuator is connected to and provides for operating the clutch, the work position of which is determined by a position sensor which supplies a measured position signal to a control device receiving an information signal and supplying a control signal for the actuator; the control device has a monitor circuit for determining malfunctioning of the position sensor and supplying a fault signal; and a virtual sensor device for estimating the work position of the clutch to supply the control device, in the presence of the fault signal, with a virtual position signal instead of the measured position signal.

Abstract: A motion transmitting apparatus wherein an electric motor, an engine or another prime mover rotates an axially fixed first part relative to a coaxial axially movable non-rotatable second part. The structure which serves to move the second part axially in response to clockwise or counterclockwise rotation of the first part includes a follower borne by the first part and a helical spring having end convolutions affixed to the first part. The follower extends between two intermediate convolutions of the helical spring. If the apparatus is utilized in the power train of a motor vehicle, the axially movable part can serve to engage or disengage or change the extent of engagement of the friction clutch between the output element of the engine and the input element of the change-speed transmission.

Abstract: The extent of engagement of an automatically adjustable friction clutch in the power train of a motor vehicle, wherein the clutch receives torque from a rotary output element of an engine and transmits torque to the rotary input element of a transmission, is determined by an electronic control unit in conjunction with an actuator which is responsive to signals from the control unit. Under normal circumstances, the adjustment of the clutch is selected on the basis of control signals which depend upon the actual RPM of the output element and the RPM of the input element. When the actual RPM of the output element departs from a desired RPM, the control signal is altered to reduce the rate of torque transmission by the clutch upon a determination that the actual RPM is below the desired RPM, and to increase the rate of torque transmission by the clutch when the actual RPM exceeds the desired RPM.

Abstract: An apparatus for protecting an automatic clutch from overheating, capable of holding down the generation of heat in the clutch even when the condition in which a traveling load at a vehicle starting time exceeds a predetermined level continues for a predetermined period of time. The automatic clutch is provided in a transmission path extending between an internal combustion engine and a transmission adapted to change a speed represented by an output from the internal combustion engine.

Abstract: A method and apparatus for controlling a motor vehicle drive train component. The motor vehicle includes an engine control device and a clutch control device. The method and apparatus control the clutch control device and the engine control device so that they do not simultaneously control or regulate the same operating parameter of the drive train.

Abstract: A method for influencing the driving dynamics of a motor vehicle wherein the vehicle speed and the transverse acceleration are feed as input signals to a regulating and control unit in which an actuation signal is produced when a limiting value of a variable which determines the driving condition is exceeded. When a limiting value of the vehicle speed and/or the transverse acceleration is exceeded, throttle-valve actuating signals for limiting the throttle-valve position are provided and when a determined change in the transverse acceleration over time exceeds a limiting value, a clutch actuating signal is produced for opening the clutch.

Abstract: In a method and apparatus for diagnosing a malfunction in a clutch actuator of a motor vehicle, the actual position of the clutch actuator is measured by a position sensor. Simultaneously, an estimated position of the clutch actuator is calculated by an emulation unit that emulates the function of the clutch actuator. Malfunctions of the clutch-actuator are diagnosed by comparing the actual, measured position to the estimated position.

Abstract: A control for shifting into a start ratio in a computer-assisted (48) vehicular splitter-type compound transmission (16) having a main section (16A) shifted by a manually operated shift lever (31) and a controller (42). The splitter section (16E) is provided with a three-position (L, H, N) actuator (46) and is commanded to a splitter-neutral position upon sensing a main section shift to neutral, master clutch (14) disengagement and low vehicle speed (OS<REF<3 MPH) to reduce the inertia of the main shaft assembly and reduce the need for a clutch brake when engaging a start ratio.

Abstract: An apparatus for controlling an automatic transmission of an automotive vehicle, which is shifted to a selected one of operating positions by an engaging action of a frictional coupling device, wherein an overshoot engagement control device is provided to shift the automatic transmission to the selected one operating position such that a shifting action of the automatic transmission is initiated while an input speed of the automatic transmission is lower than a synchronizing speed of the selected operating position. The overshoot engagement control device is arranged to control an engaging force of the frictional coupling device such that the input speed is first raised above the synchronizing speed and is then lowered down toward the synchronizing speed.

Abstract: At the time of vehicle start-up from the state of engine stopping, a hydraulic oil pressure in a starting clutch sometimes overshoots beyond a creeping pressure as a result of a rise in the hydraulic oil pressure in the hydraulic circuit, resulting in shocks. A hydraulic oil pressure command value to a linear solenoid valve which controls the starting clutch pressure is made smaller than the creeping pressure until the point of time at which the rise in the hydraulic oil pressure in the hydraulic circuit (=the point of time at which a condition of F2=1 is satisfied). Once a discrimination of a rise in the hydraulic oil pressure has been made, the command value is made higher than the creeping pressure for a predetermined period of time (i.e., for the period of YTM3−YTM3B1), and is thereafter made to the creeping pressure.

Abstract: A lock-up controller is provided for shifting a torque converter of a vehicle from the lock-up state to the unlock state when the accelerator pedal is depressed at a speed larger than a predetermined speed when the vehicle is coasting. The controller is further functioning to prevent the torque converter from shifting to the lock-up state when the torque converter has been shifted to the unlock state and the vehicle speed is within the predetermined re-lock-up prevention speed range so as to avoid frequent lock-up/unlock operation of the torque converter.

Abstract: A device and a method of controlling a progressive change of an overall transmission ratio from an old transmission ratio to a new transmission ratio are described. The method is applicable in a transmission device comprising a first and a second gear trains which are independently shiftable for determining together an overall transmission ratio of the transmission device. The method includes detecting a physical magnitude which is influenced by progressive ratio change in the second gear train, resulting in a progressive variation of said overall transmission ratio in one direction, and also includes controlling an actuator of a first selective coupling means as a function of a detected value of the physical magnitude to progressively change a transmission ratio in the first gear train in a direction contrary to the first direction.

Abstract: The present invention is directed to the remote operation of an auger attached to a portable unit for storing and transporting particulate matter. A bin having a number of sidewalls which converge downwardly and inwardly to a discharge end secured to a frame. A discharge chute is attached to the bin to receive particulate matter from the bin and transfer the particulate matter from the bin. An unloading auger is secured within the discharge chute and powered by a motor which is secured to the frame. In general operation, a clutch assembly engages the motor to the unloading auger causing the particulate matter to be unloaded. A user may use a transmitter to send a signal to a receiver which increases or decreases the output of the motor and engages or disengages the clutch such that the auger may be started or stopped. The transmitter and receiver may communicate using a radio signal. Additionally, wheels may support the frame and a trailer hitch may be attached.

Abstract: A control apparatus for an automatic transmission capable of sufficiently producing the effect of neutral control by reducing a period of time from stop of a vehicle to the release of an input clutch. Vehicle stop prediction means for predicting immediate stop of the vehicle from a vehicle speed detected by a vehicle speed sensor is provided. Input clutch control means for reducing a hydraulic pressure in a hydraulic servo of the input clutch from a hydraulic pressure in a normal engagement state to a waiting pressure capable of maintaining an engagement state of the clutch based on the prediction of the stop of the vehicle by the vehicle stop prediction means is provided. The operation of releasing the input clutch concurrent with the neutral control is started from a state of the waiting pressure, so that the input clutch is released in a short period of time.

Abstract: An apparatus and method for controlling the engagement rate of a clutch in a partially or fully automated mechanical transmission is responsive to certain calculations derived from the rotational speeds of the input member and the output member of the clutch. The apparatus includes an electronic controller which initially sets a desired speed for the vehicle engine during the shifting process, determines a rate of engagement movement of a release bearing of the clutch, and actuates appropriate valves to initiate the gradual engagement of the clutch. The electronic controller compares the actual speed of the engine with a first value. If the actual speed of the engine is greater than or equal to the first value, the electronic controller then compares the rotational speeds of the input and output shafts of the clutch in order to determine if the difference therebetween is less than a second value. In a first embodiment of the invention, the magnitude of the second value is a constant value.

Abstract: An apparatus and method for controlling the engagement rate of a clutch in a partially or fully automated mechanical transmission is responsive to certain calculations derived from the rotational speeds of the input member and the output member of the clutch. The apparatus includes an electronic controller which initially sets a desired speed for the vehicle engine during the shifting process, determines a rate of engagement movement of a release bearing of the clutch, and actuates appropriate valves to initiate the gradual engagement of the clutch. In a first embodiment, the electronic controller compares the rotational speeds of the input and output shafts of the clutch in order to determine if the difference therebetween is less than a first constant value. If so, it can be inferred that the clutch is sufficiently close to full engagement as to warrant the interruption the gradual engagement process and immediately move the release bearing from its current position to the fully engaged position.

Abstract: A system for protecting one or more drivetrain components from excessive inertial torque includes an automated clutch disposed between an internal combustion engine and a transmission coupled thereto, wherein the automated clutch is responsive to computer control. Under conditions wherein driveline acceleration exceeds an acceleration threshold, wherein the acceleration threshold preferably corresponds to the weakest of the drivetrain components, a control computer is operable to actuate the automated clutch to thereby electronically disengage the engine from the transmission, and accordingly protect the various drivetrain components from damage due to excessive engine inertial torque. In an alternate embodiment, a control computer is operable to compute or otherwise estimate engine inertial torque and actuate the automated clutch as just described if/when the engine inertial torque exceeds a torque threshold corresponding to an input torque capacity of one or more of the drivetrain components.

Abstract: The invention is directed to a system for controlling a clutch which is arranged between the motor of a vehicle generating a motor torque and the wheels of the vehicle. With this clutch, and in response to a drive signal, the force flow between the motor of the vehicle and the wheels can at least be reduced. The essence of the invention is that the drive signal of the clutch is formed in dependence upon a signal which represents a change of the motor torque of a specific extent. The invention is also directed to a system for controlling the motor of a vehicle with an adjusting element for influencing the motor torque which can be adjusted at least in dependence upon the detected command torque. When a specific extent of a change of motor torque is present, the execution of the command to adjust the motor torque is delayed.

Abstract: A clutch engaged by means of flyweights and a spring directly meshes an input sun gear and an output planet gear carrier. When engagement pressure is insufficient for torque to be transmitted, a crown wheel slows down and is stopped by a free wheel, while an axial thrust (Pac) produced by helical teeth releases the clutch, so that the device functions as a step down device. A control unit accelerates the onset of the procedure. The device enhances the comfort and reduces stresses of the transmission.

Abstract: A lock-up controller is provided for shifting a torque converter of a vehicle from the lock-up state to the unlock state when the accelerator pedal is depressed at a speed larger than a predetermined speed when the vehicle is coasting, The controller is further functioning to prevent the torque converter from shifting to the lock-up state when the torque converter has been shifted to the unlock state and the vehicle speed is within the predetermined re-lock-up prevention speed range so as to avoid frequent lock-up/unlock operation of the torque converter.

Abstract: There are disclosed a method of and an apparatus for regulating the operation of a friction clutch or another torque transmission system in the power train of a motor vehicle. The regulation is such that the operator of the vehicle is informed of a prevailing or impending condition which entails or is about to entail damage to the system or to the entire power train. Such situation can arise in response to excessive and/or prolonged slip of abutting friction surfaces in a friction clutch, overheating of one or more parts of the system for any other reason(s), as a result of improper selection of the transmission speed for starting of the vehicle and/or due to excessive wear upon the friction linings and/or other parts. The remedial undertaking can include such regulation of the system that the ride become uncomfortable to the occupant(s) of the vehicle and/or automatic elimination of the cause(s) of unsatisfactory torque transmission.

Abstract: A torque converter lock-up clutch controlling system for a vehicle drive train inputs a vehicle speed signal and an engine load signal. The vehicle drive train includes an automatic transmission operable in a manual ("M") ratio change mode when an operator selects a "M" range position. The system enables the automatic transmission to behave like a manual transmission upon selection of the "M" range position. A memory includes a "M" range lock-up shift point map for storing data which relates the lock-up application and release to the vehicle speed and engine load signals. The "M" range lock-up shift point map includes lock-up application values, which correspond to the magnitudes of the vehicle speed signal at which lock-up clutch applications are to occur. The magnitudes of the vehicle speed signal at which lock-up clutch applications are to occur are determined in a manner as a function of the magnitudes of the engine load signal.

Abstract: A lockup control system controls a lockup state of the automatic transmission employing a torque converter with a lockup clutch. The lockup control system executes a lockup clutch engagement pressure control for decreasing an engagement differential pressure of the lockup clutch at a predetermined differential pressure for a predetermined time period under a coast lockup state. Further, the lockup control system executes a learning control for obtaining the predetermined differential pressure by adding a differential pressure correction value to a differential pressure learning value by which the torque converter generates a slight slip under the coast lockup state. Therefore, even during the coast lockup state, both of suppressing vibrations by a lowering of a lockup capacity and maintaining a responsibility for re-increasing the differential pressure are ensured.

Abstract: The power train of a motor vehicle employs a torque transmitting apparatus having a hydrokinetic torque converter with a lockup clutch and a torsional damper between the output member of the clutch and the hub of the turbine in the cover of the torque converter. The torque capacity of the damper is less than the nominal torque of the engine whose output element drives the cover of the torque converter. The lockup clutch is designed in such a way that the transmission of torque from the cover to the damper can be regulated in several stages, one of which involves the transmission of torque within a range of between about 10% and 60% of the maximum torque transmitted by the engine and another of which involves the transmission of torque corresponding to not less than 60% of the maximum torque transmitted by the engine.

Abstract: The power train of a motor vehicle has an automated clutch and a control unit which causes one or more actuators to change the rate of torque transmission by the clutch from the engine to the transmission of the power train in response to appropriate signals from various sensors. When the transmission is shifted into gear while the engine is idling, while the brake or brakes are not applied and while the gas pedal is not depressed, the setting of the clutch is such that the transmission causes the motor vehicle to carry out a crawling movement as a result of a change of the rate of torque transmission by the clutch from the idling engine to the transmission from a first value (e.g., zero) to a second value as a function of the monitored temperature of the clutch.

Abstract: A fuzzy control method of a damper clutch and, more particularly, a fuzzy control method enhances engine brake effect by directly connecting a pump to a turbine by engaging the damper when a shift control unit identifies an engine brake state. The fuzzy control method of a damper clutch includes receiving or checking input signals relating to a damper clutch; controlling shift timing by a fuzzy control; determining if an engine brake should be used or not; checking an amount of driver's engine brake will if the engine brake should be used; determining if an emergency brake should be used or not; engaging the damper clutch when an emergency brake should be used; and controlling the damper clutch through a normal control when both the engine brake and emergency brake are not used.

Abstract: In a fluid pressure control system for a continuously variable transmission, a valve for regulating a torque converter pressure is a pilot actuated valve having a pressure increasing side pilot port for receiving a control pilot pressure for controlling a line pressure and a pressure decreasing side pilot port for receiving a second pilot pressure. A selector valve is switched between a first state for allowing the supply of the second pilot pressure to decrease the torque converter pressure supplied to the torque converter and a second state for draining the second pilot pressure to increase the torque converter pressure. By controlling the selector valve, a control unit increases the torque converter pressure in a wide throttle high speed vehicle operation with the torque converter in a lockup state to ensure the lockup engagement and in a wide throttle starting operation with the torque converter in a non-lockup state to prevent an engine stall.

Abstract: An engine-transmission drivetrain includes a torque converter situated between the engine output shaft and the transmission. The torque converter includes a lock-up clutch. A speed sensor, which measures the rotational speed of an output shaft of the transmission, generates a pulse signal. A transmission controller includes a deceleration dependent lock-up release command generator and a torque converter speed dependent lock-up release command generator. The pulse signal from the speed sensor is used as inputs to both of the lock-up release generators. In the deceleration dependent lock-up release command generator, the pulse signal is processed to derive information as to the magnitude of deceleration which the transmission output shaft is subject to. In the torque converter speed dependent lock-up release generator, the pulse signal is processed to derive information as to rotational speed of an output element of the torque converter.

Abstract: A control for a vehicle drive line system (10) including an automated vehicle master clutch (14) drivingly interposed in between a fuel-controlled engine (12) and the input shaft (20) of a mechanical transmission. At sensed idle conditions (THL<REF and OS<REF), the engine (12) is commanded to generate an output torque (T.sub.FW) equal to a selected idle drive torque (T.sub.IDLE) at idle speed (ES=IDLE), the engine is commanded to rotate at idle speed and the clutch, preferably a wet clutch, is caused to engage with a torque capacity equal to the idle drive torque.

Abstract: A control system of a lockup clutch of a torque converter of a vehicle automatic transmission. A basic manipulated variable is determined in response to the vehicle operating condition in accordance with a predetermined characteristic, and the lockup clutch engaging force is controlled in response to the variable. In the system, fuzzy reasoning is carried out using the detected vehicle operating parameters to correct the basic manipulated variable, and the engaging force is controlled in response to the corrected manipulated variable, when the control condition is met. The corrected manipulated variable is gradually decreased with respect to time when the vehicle driving state has shifted from a region in which the engaging force is controlled in response to the corrected manipulated variable to a region in which the lockup clutch is disengaged.

Abstract: An engaging force control system of a fluid coupling is provided with a fluid coupling disposed between an input element connected with an engine and an output member connected with a drive wheel side member and including a lock-up clutch which is selectively engaged with and disengaged from the input and output elements, an engaging force adjusting device for adjusting the engaging force of the lock-up clutch, a throttle opening sensor for sensing a value related to a throttle opening of the engine, a vehicle speed sensor for sensing a value related to a vehicle speed of a vehicle, an engaging force control device for controlling the engaging force adjusting device based on an engaging property which is predetermined based on the values related to the throttle opening and vehicle speed as parameters and the values sensed and, an uphill detecting device for detecting an uphill running condition of the vehicle.

Abstract: A slip control system for a torque converter with a lockup clutch comprises a controller from which a slip control signal is outputted to a slip control actuator of the torque converter. The controller is arranged to calculate a reference value of a lockup clutch engagement pressure on the basis of a characteristic of the torque converter, to calculate a difference canceling lockup clutch engagement pressure for adjusting an actual slip rotation speed to the target slip rotation speed, to obtain the sum of the lockup clutch engagement pressure reference value and the difference canceling lockup clutch engagement pressure as a lockup clutch engagement pressure command value, and to output the control signal indicative of the lockup clutch engagement pressure command value to the actuator.

Abstract: A drive train arrangement for a motor vehicle driven by an internal combustion engine. The engine output or torque of the internal combustion engine (1) is controllable by means of an engine output control (11) via a user-operated accelerator pedal (15). A friction-gearshift clutch (3) is arranged in the torque transmission path of the internal combustion engine (1). To allow the friction-gearshift clutch (3) to be designed for reduced transmission reliability, a slip control (39) reduces the engine output or torque of the internal combustion engine (1) for a time-limited period via the engine output control (11) when the friction-gearshift clutch (3) slips in its fully engaged state. To this end, the slip control (39) responds to a clutch position sensor (41) that detects the engagement position of the friction-gearshift clutch (3), and to speed sensors (43, 45) that detect the input and output speeds of the friction-gearshift clutch (3).