Abstract: A shift control device is provided for reducing a shock generated at a clutch engagement moment in a gearshift operation in a straddle type vehicle having a shift control device that makes the clutch operation and the gearshift operation using the power of an actuator. The actuator is controlled based upon a rotational position and a speed of a shift shaft. When the rotational position of the shift shaft is located between a first position and a second position, the shift shaft is rotated at a speed slower than a rotational speed at which the shift shaft is rotated before reaching the first position to engage a gearshift clutch at a low speed. The first position and the second position are set in such a manner that the gearshift clutch is in a halfway engaged state when the shift shaft is located at a rotational position between the first position and the second position.

Abstract: A control unit of an at least temporarily four wheel-driven motor vehicle is provided. The control unit is arranged such that a displacement path for an actuator that actuates a transmission clutch is assigned to a setpoint clutch torque via a characteristic curve, and when at least one defined operating condition is present, ensures stable operation of the wheels. The control unit specifies a displacement path which according to the characteristic curve results in a not completely locked state of the transmission clutch, and subsequently computes the actual clutch torque from only the drive slip on the front axle, the drive slip on the rear axle, and the total drive torque.

Abstract: A method for controlling a hydraulic circuit for a twin-clutch transmission, wherein the hydraulic circuit comprises a first and a second clutch that can be hydraulically actuated, the pressures of said clutches being controlled with respective pressure control valves, and wherein a safety circuit substantially guarantees a safe state for the hydraulic circuit if a malfunction occurs. The safety circuit is configured such that if a partial malfunction affecting only one of the two clutches occurs, the affected clutch is disengaged and if a total malfunction affecting both clutches occurs, the clutch with the lower clutch pressure at the time of the total malfunction is disengaged and the other clutch with the higher clutch pressure at the time of the total malfunction remains engaged to maintain the transfer of torque via said clutch.

Abstract: A control unit of a control system for an at least temporarily four wheel-driven motor vehicle is arranged such that a displacement path for an actuator that actuates a transmission clutch is assigned to a setpoint clutch torque via a characteristic curve, and the control unit checks whether slip of the transmission clutch occurs when a displacement path is specified that should result in an at least fully locked state of the transmission clutch according to the characteristic curve.

Abstract: In automatic shift control apparatus and method for a manual transmission, at least one clutch is interposed between an engine and the manual transmission and a controller performs a feedback control for an engagement force of the clutch after a gear shift for the manual transmission is ended in such a manner that an input revolution speed of the clutch is directed toward another revolution speed thereof after the gear shift occurs at a predetermined time variation rate, the controller setting mutually different feedback control gains in a variation region of the input revolution speed of the clutch in which the input revolution speed of the clutch is directed toward the other revolution speed after the gear shift occurs and in a convergence region of the input revolution speed in which the input revolution speed of the clutch has reached to the other revolution speed after the gear shift occurs.

Abstract: Power train control unit 100 controls friction clutch 203 when shifting from one cogwheel row to the other cogwheel row, sets the target synchronous rotation speed based on the output rotation speed of a transmission and parameters indicative of the state of engine 1 or the transmission, and sets the command value to the friction clutch so that the input rotation speed can be synchronized with the target synchronous rotation speed. Control unit 100 sets the target shifting required time based on parameters indicative of the state of engine 1 or the transmission, and corrects the command value to the friction clutch so that the required shift time can approach the above target shift required time.

Abstract: A method for controlling at least two clutches in a twin-clutch gearbox of a motor vehicle, wherein at least one clutch is opened by at least one emergency valve. A twin-clutch gearbox of a motor vehicle, consisting of at least two clutches actuated by at least one clutch actuator by means of a release system, especially for carrying out said method, whereby an emergency valve is provided in order to open at least one clutch.

Abstract: A clutch is operated by an actuating pressure pressure during an engaging process of the clutch. The actuating pressure is controlled over time such that predetermined characteristics for an engagement of said clutch are approximated by starting a process for changing a rotational speed of an output shaft of the torque converter for an adaptation of the rotational speed to an actual velocity of the vehicle during engagement of the clutch. An ideal signal for the rotational speed is determined which corresponds to an estimate for an engagement of the clutch with the predetermined characteristics. An actual signal of the rotational speed of the output shaft over time is measured during said process. Deviations are determined between the actual signal and the ideal signal. Finally the signal of the actuating pressure over time is automatically changed in order to reduce the deviations between the actual signal and the ideal signal if the deviations exceed a threshold.

Abstract: A control device for a vehicle which has a function to reduce the change-speed shock when changing the speed by controlling the transmission of the vehicle. The control device performs the switching between a manual change-speed mode in which the vehicle speed can be changed based on a change-speed command generated by manual operation and an automatic change-speed mode in which a transmission gear ratio can be controlled based on the predetermined change-speed characteristic. Thereby the reduction amount of the change-speed shock can be changed between the manual change-speed mode and the automatic change-speed mode.

Abstract: In a method of operating a motor vehicle with an electronically controlled automatic clutch device, a control device and one or more data-storing devices for values of operating quantities and parameters, the values are stored in at least duplicate form in the data-storing device. The data are stored in prescribed formats and the integrity of the data is checked according to prescribed criteria, to ensure that incorrect data are not used in the operation of the vehicle.

Abstract: The invention relates to a process for carrying out an automated clutch actuation of a motor vehicle with a drive engine and a transmission, connected to said drive engine by way of a clutch, in which process the clutch exhibits both an opened and a closed operating position, whereby to introduce unpowered operating phases the clutch is transferred by means of automation into the opened operating position and to introduce powered operating phases it is transferred by means of automation into the closed operating position. To design such a process more reliably and comfortably, the variables, from which a dangerous situation in time or its termination can be concluded with a certain probability, are measured, according to the invention, so that the clutch can be moved into an operating position (opened or closed), which makes it possible to carry out faster the subsequent request of the driver—such as an acceleration request or a braking request.

Abstract: A method for adaptively learning clutch volumes and fill level to compensate for build tolerances and clutch wear includes increasing a fill level of a clutch during an oncoming fill phase of a clutch to clutch transmission. A state of a regulator valve of the clutch to clutch transmission is monitored during the oncoming fill phase. Fill level of the clutch is adjusted before a next shift based on whether the regulator valve switches from a regulating state to a full feed state before elapse of a valid shift time.

Abstract: An automatic-clutch control system of a transmission for a vehicle is arranged to calculate a deceleration of the vehicle when shifting is not being executed, when an automatic shift mode is being selected, when an idle switch is set at ON state, and when a brake switch is set at OFF state, and when the vehicle is being decelerated. Further, the automatic-clutch control system decreases an engagement force of the automatic clutch according to an increase of the deceleration and a decrease of a vehicle speed to vary the engagement state.

Abstract: A control system of a continuously variable transmission for a vehicle compensates for delays in an estimated input torque TINE based on a gradient value (variation) of the estimated input torque TINE,. For example, a friction force being applied to a driving belt of a continuously variable transmission is regulated according to the compensated estimated input torque TINE. Accordingly, an appropriate torque transmitting capacity is maintained in the transmission even at a rapid accelerating operation of the vehicle, while realizing good fuel efficiency.

Abstract: A controller (12) controls the engaging force of a lockup clutch (2c) connecting an engine (1) and an automatic transmission (3) via an engaging force regulating mechanism (11, 13). The controller (12) sets a target relative rotation speed (?SLPT) according to a difference between a target engine rotation speed (TGT_EREV) and an input rotation speed (PriREV) of the automatic transmission (3). When an initial engine rotation speed (ST_EREV) is smaller than the target engine rotation speed (TGT_EREV), the controller (12) causes the target relative rotation speed (?SLPT) to gradually vary from an initial relative rotation speed (ST_SREV) to a predetermined target change-over relative rotation speed (CHG_REV). By controlling the engaging force regulating mechanism (11, 13) on the basis of the target relative rotation speed (?SLPT) set in this way, a prompt and appropriate lockup operation of the lockup clutch (2c) is realized in response to the vehicle conditions.

Abstract: Systems and methods for controlling shift and throttle of an electronically controlled power train are disclosed. The system includes a throttle or shift controller having an operating range. An hydraulic slave is in fluid communication with the controller such that a movement of the controller within its operating range causes a flow or displacement of fluid between the controller and the hydraulic slave. The hydraulic slave has a shaft that rotates in response to the fluid flow between the controller and the hydraulic slave. The shaft is adapted to be coupled to a position sensor such that rotation of the shaft causes the position sensor to produce electrical throttle control signals that represent the movement of the controller within its operating range. The electrical signals can be adapted to cause the power train to set an engine throttle and a transmission shift position according to a current position of the controller within its operating range.

Abstract: A method of controlling the torque transferred across the engaged clutch of a vehicle having a dual clutch transmission to provide predetermined engine acceleration for each gear based on the engine throttle position and subsequent changes of clutch speed that are in response to operatively varying the torque transferred across the engaged clutch as the engine accelerates to a predetermine speed based on the throttle position. The method includes the steps of determining the engine throttle position, determining the currently engaged gear of the transmission, and sensing the speed of the driven member of the engaged clutch. Then, a target engine speed is determined based on the engine throttle position, the currently engaged gear, and the clutch speed. The torque transferred across the engaged clutch is then continuously varied to cause the engine to accelerate toward the target engine speed.

Abstract: A power transfer apparatus 1 of a four-wheel drive vehicle includes, a clutch, an inversion detector, and controller. The clutch generate an engagement force that effects a driving force output from an engine to wheels of the vehicle via a transmission. The transmission includes the inversion detector 23, 27 for detecting inversion or non-inversion of a gear-shifting direction of the transmission 13. The controller 23 subjects the electromagnet to energization control such that torque to be transmitted by the clutch is decreased to a target value in accordance with an inversion signal pertaining to said gear-shifting direction detected by said inversion detector 23, 27.

Abstract: A power transmission comprises a continuously variable transmission CVT, which transmits a rotational driving force from an engine E, a starting clutch 5, which variably sets the transmission capacity for the continuously variable transmission CVT, and a control valve CV, which controls the engagement operation of the starting clutch 5. While the engine E is in a partial cylinder operation mode, the control valve CV controls the engagement operation of the starting clutch 5 to attain a predetermined transmission capacity at a rotational speed of the engine that is higher than for a case of the engine in an all cylinder operation mode.

Abstract: A power transmission comprises an engine E with a plurality of cylinders, a belt-type continuously variable transmission CVT, which changes the rotational speed being transmitted from the engine, a control valve CV, which variably sets the line pressure used for controlling the speed change ratio of the transmission, and an electrical control unit ECU, which calculates the torque of the output shaft of the engine when the engine is decelerating in a partial cylinder operation mode. While a vehicle equipped with this power transmission is decelerating with the engine being in a partial cylinder operation mode, the control valve CV sets the line pressure in correspondence to the torque of the engine output shaft calculated by the electrical control unit ECU.

Abstract: A transmission system is comprised of a twin-clutch transmission which comprises a first clutch for selecting a first gear-ratio group and a second clutch for selecting a second gear-ratio group. A control unit for controlling the twin-clutch transmission is arranged to calculate an estimated engine revolution speed produced in the event that one of two gear ratios adjacent to the present gear ratio is selected by executing one of upshift and downshift, and to disengage one of the first and second clutches which is engaged to select the gear-ratio group including the other of the two gear ratios adjacent to the present gear ratio when the estimated engine revolution speed is out of a normal operation speed range.

Abstract: The invention relates to a method for manually stipulating the transmission ratio of a continuously variable transmission (CVT) for a motor vehicle. The CVT comprises a control device, a shifting or selecting device, a starting element and a variator for adjusting the transmission ratio which is driven, in particular, by an internal combustion engine. The control device processes input signals derived from a driver-vehicle system within the framework of an operational strategy for stipulating the transmission ratio, the rotational speed of the drive motor or a variator input rotational speed. In a first automatic operation mode, the operational strategy automatically selects the transmission multiplication. In a second manual operational mode, the driver can directly intervene, via the shifting or selecting device, in the selection of the transmission multiplication.

Abstract: A hill hold control apparatus of an automatic transmission having a plurality of drive gears mounted on an input shaft, a plurality of driven gears meshing with the respective drive gears and mounted on an output shaft and a bypass clutch for engaging the input shaft with the output shaft, includes a grade judging means for judging that the vehicle travels on a grade, a shift gear train detecting means for detecting a shift gear train of the automatic transmission, a foot brake operation detecting means for detecting an operation of a foot brake and a control means for engaging the bypass clutch when it is judged that the vehicle is in standstill and the shift gear train is a start gear train and the foot brake is inoperative based on respective signals of the grade, the shift gear train and the operation of the foot brake.

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: An automatic start controlling apparatus for automatically starting an internal combustion engine. A transmission is coupled to the engine. The transmission has a clutch, which is actuated by an oil pump other than the engine when the engine stops. The transmission has an input shaft and an output shaft. The input shaft is connected to the engine. The automatic start controlling apparatus has a controller. When the engine is automatically started, the controller detects whether the clutch is completely engaged. When the controller judges that the clutch is partially engaged, the controller reduces the output torque of the engine or limits an increase of the output torque.

Abstract: A method of monitoring a torque transmission system with a manually switchable gearbox in the power train of a motor vehicle involves the utilization of at least one sensor unit at the input side of the torque transmission system to ascertain relevant positions of the shift lever of the gearbox and the driving torque of the engine of the motor vehicle. The thus obtained shift lever signals are memorized, together with comparison signals which are obtained as a result of filtering of the shift lever signals, and various characteristics of such signals are recognized and identified to indicate the intention of the operator of the vehicle regarding the switching of the gearbox. The thus obtained switching intention signals are transmitted to a controlled clutch operating system.

Abstract: A synchronous meshing type automatic transmission control system is provided to be capable of shortening a time for gear change without generation of noises from gears and degradation of a synchronizing mechanism in durability, and comprises an internal combustion engine mounted on a vehicle, a speed change mechanism coupled to the internal combustion engine through a clutch, a shift-select actuator for selectively coupling one set of a plurality of sets of speed change gears having different gear ratios and intervening between an input shaft coupled to the clutch of the speed change mechanism and an output shaft for driving the vehicle, and a control device for inputting thereinto an output signal of a shift-select position sensor, which detects a selected position of the shift-select actuator, to operate a position of the shift-select actuator for gear change and for putting the clutch in weak coupling in a state, in which no gear is coupled between the input shaft and the output shaft in the course of gear

Abstract: Control of shiftable clutches by a clutch control signal that is a function of the difference between the actual and desired engine rotational speeds and of the gradient of the actual engine rotational speed and wherein the clutch control signal values are generated by the employment of a set of clutch engagement and disengagement speed curves.

Abstract: A torque-transmitting system for vehicles has a main drive clutch operable by means of a clutch-actuator, a transmission, a shift mechanism for setting the transmission ratio, a selector lever allowing the driver to select between a neutral mode or a drive mode of the transmission, and electronic control means for controlling the clutch actuator and the shift. mechanism. The electronic control means will cause the clutch-actuator to disengage the clutch when the engine is started and to re-engage the clutch if the transmission has been left in neutral mode for a preprogrammed time period while the vehicle is standing still, so as to turn the input shaft of the transmission and thereby warm up the transmission oil.

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 method of monitoring a torque transmission system with a manually switchable gearbox in the power train of a motor vehicle involves the utilization of at least one sensor unit at the input side of the torque transmission system to ascertain relevant positions of the shift lever of the gearbox and the driving torque of the engine of the motor vehicle. The thus obtained shift lever signals are memorized, together with comparison signals which are obtained as a result of filtering of the shift lever signals, and various characteristics of such signals are recognized and identified to indicate the intention of the operator of the vehicle regarding the switching of the gearbox. The thus obtained switching intention signals are transmitted to a controlled clutch operating system.

Abstract: A method/system for controlling an automated mechanical transmission system (10) utilized on a vehicle. To protect from driveline damage due to improper clutch engagement during vehicle launch conditions, the master friction clutch (16) is partially engaged to determine a direction of rotation of the input shaft (18) from the non-directional signal (IS) received from a non-directional speed sensor (36).

Abstract: An electro-mechanical clutch actuator system is provided for a transmission having dual input shafts with respective clutches and with a plurality of drive gears rotatably mounted to each input shaft and having synchronizer mechanisms for engaging each drive gear to one of the input shafts. The clutch actuators include an electric motor and a reduction gear assembly for moving a pawl tweeter arm and is assisted by an assist spring. The movement of the pawl tweeter arm transmits torque through a pivot arm which in turn, act to engage or disengage its corresponding clutch. An upshift clutch control algorithm is provided to facilitate shifting to a higher gear, which monitors and regulates movement of the clutch actuator motors.

Abstract: A method for controlling a damper clutch release control system which performs duty control in releasing a damper clutch for down-shifting in a sports mode during a throttle valve on state and thereby decreases gear-shift shock, the method comprising:

Abstract: A shift control system of an automatic transmission executes an interchange shift by interchanging engagement conditions of first and second friction elements of the automatic transmission. The first and second friction elements are engaged and disengaged according to oil pressures supplied thereto. A controller of the shift control system is arranged to decrease the second oil pressure of the second friction element by a second predetermined gradient and to increase the first oil pressure of the first friction element by a first predetermined gradient after the loss stroke of the first friction element is terminated, and to determine the first gradient such that a difference between a command pressure and an actual pressure of the first friction element is kept substantially constant.

Abstract: Device for controlling a clutch, which is connected to an actuator, which can activate the clutch itself; the control device comprises a position sensor, which can detect the position of the clutch, in order to supply a measuring position signal to a main control device, which receives as input information signals, and generates as output a control signal to control the actuator, a monitoring circuit, which can detect a state of malfunctioning of the position sensor, in order to supply a malfunctioning signal, and an auxiliary control device, which can be activated in the presence of a malfunctioning signal, in order to transfer control of the actuator from the main control device to the auxiliary control device.

Abstract: A pressure control apparatus and method are provided for controlling hydraulic clutches of a backward and forward drive switching device mounted in a transmission of a working vehicle such as a tractor. When a backward and forward drive switching shuttle lever is operated, a current supplied to an electromagnetic proportional valve is controlled to gradually increase the pressure for a hydraulic clutch corresponding to a direction of movement. When a propelling drive connecting and disconnecting clutch pedal is operated, the pressure for that hydraulic clutch is controlled through the electromagnetic proportion valve, based on a depressed position of the pedal. When the operator switches the shuttle lever from forward to backward or vice versa, a microcomputer causes the shuttle control current to rise at a point of time of start of a clutch engaging operation of the clutch pedal.

Abstract: A clutch control device of a continuously variable transmission is provided with a clutch control part, which controls the engagement state of a clutch. The minimum engaging force, which is capable of maintaining the completely engaged state of the clutch, is predetermined to increase according to an increase in engine torque. The clutch control unit has an engaging force setting part, which sets the target engaging force for the clutch to a higher value than the minimum engaging force by a predetermined value. The clutch control unit controls the engagement state of the clutch so that the actual engaging force for the clutch can be higher than the minimum engaging force by the predetermined value. Therefore, the clutch control device can improve the fuel economy and prevent a shift shock when there is a rapid increase in the engine torque.

Abstract: A power transmission arrangement for a vehicle adapted to transmit a drive power from an engine to a transmission via a wet multi-plate clutch. An electronic controller automatically disengages and engages the clutch normally, but does not engage the clutch if a transmission gear position other than a predetermined one is selected for starting of a vehicle. This prevents clutch engagement with an excessively high gear position. Otherwise, the clutch would overslip and be deteriorated soon. A torque converter may further be provided in tandem to the clutch so that the engine power is transmitted to the transmission through the clutch and torque converter.

Abstract: A multiple-ratio transmission with planetary gearing and a friction clutch and brake for controlling relative motion of the gearing to establish multiple driving ratios between an internal combustion engine and vehicle traction wheels, the clutch and brake include a forward drive clutch and a reverse drive clutch for establishing torque flow paths through the gearing. The forward drive clutch establishes a torque flow path through the gearing from the engine through a torque output element of the transmission during vehicle startup in forward drive range, and the reverse clutch establishes a corresponding torque flow path during startup in reverse. A mechanical connection between the torque input shaft of the gearing and the crankshaft is characterized by minimal rotating mass, thereby reducing the inertia of rotating mass of the elements of the transmission.

Abstract: An automatically controllable clutch is arranged between the engine and the driving wheels in the transmission line of a motor vehicle. A transmission can be shifted arbitrarily or manually between idling and at least one driving position. An accelerator pedal or the like control the power of the engine, and a control device controls the clutch as a function of defined parameters detected by assigned sensors. When the driving position is engaged and the accelerator pedal is not operated, the clutch operates at its gripping point and transmits a low torque which is sufficient for a creeping of the vehicle on a level road or at a very low tractive resistance. When an approximated synchronism of the clutch input and the clutch output has been reached during the phase with an engaged driving position and while the accelerator pedal is not operated, the clutch is closed when the accelerator pedal is operated while maintaining the synchronism.

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: A vehicle transmission system includes an automated clutch operator. An electronic controller determines when the transmission is in a neutral condition and controls the automated clutch operator to move the clutch into a non-engaged condition. The electronic controller also determines when the vehicle engine is operating at an idle speed and causes the automated clutch operator to move the clutch into a non-engaged condition only when the engine is idling and the transmission is in a neutral condition, which eliminates neutral idle gear rattle.

Abstract: A hydraulic circuit for an automatic transmission operable to reduce time delay in shifting includes a source supplying pressurized fluid through a feed orifice and a charging circuit including an accumulator. The accumulator is downstream of the feed orifice, and operates to reserve pressurized fluid supplied by the source. The hydraulic circuit also includes a clutch circuit, downstream of the charging circuit, which has a clutch hydraulically actuated and operable to generate torque to shift the automatic transmission. A valve is interposed between the charging circuit and the clutch circuit to open a flow path therebetween to start a shift cycle of the clutch. When the valve is actuated, the pressurized fluid is released from the accumulator and flows to the clutch circuit to minimize delay in the shift.

Abstract: An arrangement for operating an automated friction clutch in a mechanical drive train of a motor vehicle driven by an internal combustion engine. A clutch operator actuator, by means of which a clutch operator of the clutch can be adjusted between at least one engaged position, in which the clutch is engaged at least partly for transmitting a torque, and a de-clutched position in which the clutch is completely de-clutched. An electronic control device controlling the clutch operator actuator. The electronic control device responds to a clutching requirement signaling device, which can be operated by an operator, and is designed for the purpose of supplying an engaging control signal which changes the position of the clutch operator from the de-clutched position to the engaged position to the clutch operator actuator in response to a clutching requirement signaled with the engine switched off and the clutch de-clutched.

Abstract: The invention concerns an automatic clutch in the drive train of a motor vehicle having a transmission with manual or voluntary selection of the different gears. After a gear-change, the engagement of the clutch is controlled as a function of the shift speed during the gear-change, such that, at high shift speeds, only a shortened clutch slip phase can occur.

Abstract: To perform simple and precise shift changes without using a change pedal and a change lever. In conjunction with the engagement and disengagement of a transmission clutch, a shift spindle rotates a shift drum to establish predetermined gear levels, and is rotatably driven via moderator gears by a motor. By operating a shift up switch or shift down switch not illustrated, the motor rotates the shift spindle in a prescribed direction, the transmission clutch and shift drum.

Abstract: A method of determining, during a clutch re-engagement process, the kiss-point of a vehicle clutch (14) having a driven plate (40) which drives a vehicle from an engine (10) via a multi-ratio transmission (12).

Abstract: The invention concerns an automatic clutch in a motor vehicle drive train. During travel, the clutch is controlled with excess contact pressure such that the transmissible moment of the clutch exceeds the engine torque by a predetermined amount. At low speeds or in low gears and/or when travelling slowly, the amount of excess contact pressure is considerably reduced. At high speeds or in high gears and/or at when travelling fast, the clutch is set at the maximum transmissible moment.

Abstract: A system and method for decreasing the time required to complete a ratio change in an electronically enhanced powertrain system is provided. The powertrain system includes a number of devices for providing a retarding torque to engine rotation to increase the decay rate of the engine speed during an upshift. These devices include an engine brake and an input shaft brake. A retarding torque is also provided by increasing engine accessory load by controlling various engine accessories such as a cooling fan, an air compressor, a hydraulic pump, an air conditioning compressor, and an alternator.