Abstract: A system and method of dithering speed and/or torque for shifting a transmission of a vehicle having an engine, a reversible, variable displacement hydraulic motor/pump which can be driven by the engine, a hydraulic accumulator supplied by said motor/pump, and at least one reversible hydraulic driving motor for propelling the vehicle supplied with fluid by the hydraulic accumulator and/or by said motor/pump operating as a pump. A transmission unit connects the engine with the variable displacement hydraulic motor/pump during a first mode of operation (city mode) and connects the engine to a vehicle drive wheel during a second mode of operation. The system utilizes stored hydraulic energy to dither the output of the driving motor in order to achieve quick and smooth shifts between city and highway mode, or between various ranges within the city mode.

Abstract: A clutch control device includes: a plurality of hydraulic clutches built into a transmission; a clutch switching pattern storage device in which a plurality of clutch switching patterns, each defining engage/release changeover timing with which the plurality of hydraulic clutches are engaged/released are stored in correspondence to individual speed change patterns adopted by the transmission; a clutch switching pattern selection device that selects a clutch switching pattern stored in the clutch switching pattern storage device in correspondence to a speed change pattern for the transmission at a time of speed change; and a hydraulic control device that executes hydraulic control for the plurality of hydraulic clutches in correspondence to the clutch switching pattern selected by the clutch switching pattern selection device.

Abstract: A gear ratio control device includes a controller configured to control gear ratio in a vehicle. The controller is configured to adjust an eccentricity of first supporting points of the eccentric discs so that, in the event of starting a power source in a state in which the power source is stopped and the vehicle is traveling, the gear ratio at a continuously variable transmission is at a target value, in parallel with performing start control of the power source.

Abstract: A method of controlling a rolling or a coasting function of a vehicle, such as a commercial vehicle, having a drive train including a drive motor, an automatic or automated transmission that is controllable by transmission controls, a controllable shifting mechanism for interrupting the flow of power in the drive train, and a driving speed control device. The flow of power in the drive train is interrupted in a suitable driving situation. In order for the rolling or the coasting function to be exploited as efficiently as possible, and still be terminated safely and comfortably, the flow of power in the drive train is restored depending on a selectable difference in speed (?v_F_T) between the current vehicle speed (v_F) and a speed limit (v_T) set by the driving speed control device.

Abstract: A method is proposed for controlling a through-connection clutch of a vehicle, in which an interlocking portion of the clutch is opened when the drive-train is virtually free from torque, a shifting operation is then carried out, and after the shifting operation the clutch is closed again. According to the invention, the torque transmitted by the interlocked connection in the clutch is influenced by controlling the motor in order to produce a torque-free condition at the interlocked connection in the clutch, in such manner that the interlocked connection is pre-stressed before the torque-free condition has been reached and separated immediately only when the torque-free condition is reached.

Abstract: A method of controlling a dual-clutch transmission in a motor vehicle, including two partial drivetrains, each having a plurality of gears, which each can be connected to a crankshaft of an internal combustion engine by means of a friction clutch, the method having the following steps: the first friction clutch transmits a torque to the first partial drivetrain assigned to it; the second friction clutch transmits at most a negligible torque to the second partial drivetrain; and the two partial drivetrains have a common differential, where when there are changes in torque and the amount of torque to be transmitted is low, and there is downshifting into a gear with a high transmission ratio in the first partial drivetrain, downshifting occurs into a gear with a low transmission ratio in the second partial drivetrain, and preliminary torque is applied to the differential by this gear.

Abstract: An exemplary control device includes an input torque detection unit that detects an input torque input to the input shaft; and a controller that: determines torque distribution of two of the friction engagement elements that form the shift speeds; and calculates a transmission torque of the two friction engagement elements based on the input torque and the torque distribution and sets the engagement pressure to obtain a torque capacity that can transmit the transmission torque, wherein the controller sets the engagement pressure such that slippage does not occur in the two friction engagement elements in a state where engagement of the two friction engagement elements forms the shift speeds and such that, even if an additional friction engagement element engages based on the line pressure while the two friction engagement elements are engaged, one of the three friction engagement elements is caused to slip.

Abstract: A multi-ratio rotorcraft drive system and a method of changing gear ratios thereof are disclosed. According to one embodiment, the multi-ratio rotorcraft drive system comprises a rotor system comprising one or more rotors and one or more engines. Each engine of the one or more engines is coupled to the rotor system through a multi-ratio transmission. The multi-ratio transmission comprises an output shaft coupled to the rotor system, an input shaft coupled to a respective engine of the one or more engines, a high speed clutch integrated into a high speed gear train, and a low speed clutch integrated into a low speed gear train. The high speed clutch and the low speed clutch are freewheeling clutches without a friction plate and are capable of disconnecting the output shaft and the input shaft in an overrunning condition when the output shaft spins faster than the input shaft.

Abstract: A vehicle control apparatus for a vehicle that includes a brake mechanism that produces braking force through the actuation of a first actuator and a shift mechanism that changes the shift position of a transmission through the actuation of a second actuator. The vehicle control apparatus includes: a controller that controls the electric power supplied to the first actuator and that controls the electric power supplied to the second actuator; a first electric power supply unit that supplies electric power to the controller; a second electric power supply unit that supplies electric power to the first actuator; and a third electric power supply unit that supplies electric power to the second actuator.

Abstract: A method for controlling an inching procedure of a motor vehicle, which has at least one friction clutch arranged between a drive unit and a transmission. The torque of the clutch is specified by a control unit and set by a clutch actuator. If the brake and load lever are not actuated, a multi-stage is started by an torque set by the clutch. To perform the process, the torque is increased up to a specified maximum limit to reach a specified speed in a first stage. A specified time period is waited in a second stage if the specified speed does not reached the maximum limit. The torque is increased by a specified value in a third phase if the specified speed is not reached, and the torque is reduced in a fourth stage and a driver warning is output if the specified speed again is not reached.

Abstract: A gear change control device is provided for a straddle-type vehicle having a clutch and a transmission. The device includes a clutch actuator configured to engage and disengage the clutch. A transmission actuator is configured to change a gear of the transmission. At least one sensor is configured to sense an operational condition of the straddle type vehicle. At least one switch is configured to generate a gear change command. A controller is operatively connected to the clutch actuator, the transmission actuator, the at least one sensor, and the at least one switch. The controller is configured to change gears in response to the gear change command and during the gear change reengage the clutch under either a first control routine or second, different control routine based upon the operational condition of the straddle-type vehicle determined by the at least one sensor.

Abstract: A shift transmission control device of a vehicle includes a transmission, a clutch, a shift transmission controller, and a shift inhibition state detector. The shift transmission controller is configured to control the transmission and the clutch. The shift inhibition state detector is configured to detect based on a running state of the vehicle that a predetermined shift inhibition condition is satisfied. The transmission is capable of providing a preliminary change gear ratio while the predetermined change gear ratio at which the rotational drive force is transmitted to the drive wheel is maintained. The shift transmission controller is configured to control the transmission to inhibit a change of the predetermined change gear ratio at which the rotational drive force is transmitted to the drive wheel and to provide the preliminary change gear ratio in response to the running state of the vehicle when the shift inhibition condition is satisfied.

Abstract: A method for controlling a vehicles drivetrain including an engine and automatic transmission, such that transmission ratios are shifted within a range of transmission ratios in a continuous and/or stepped manner as function of preset target speeds that are adjustable via a vehicle speed control and actual vehicle inclinations in relation to the vehicles longitudinal axis. When the actual speed of the vehicle differs from a preset threshold speed, a request to change an actual ratio of the transmission is generated, if it has been determined that the output torque is smaller than a threshold value or an output torque required to adjust the preset threshold speed of the vehicle. The ratio of the transmission is shifted so the torque applied to the output is modified toward the output torque required to adjust the threshold speed.

Abstract: A construction vehicle includes a control unit configured to shift gear after performing pre-shifting to couple a target speed-change gear that corresponds to a target speed with a target speed-change shaft in non-transmitting state of rotation of the input shaft when the gear shift is performed from a current speed to the target speed, in a state in which the current speed gear that corresponds to the current speed step and the current speed-change shaft that corresponds to the current speed gear are coupled. When the vehicle speed detected by the vehicle speed detecting section is zero, the control unit is configured to perform pre-shift auxiliary control prior to the pre-shifting control to input the rotation of the input shaft to the target speed-change shaft in a state in which the target speed-change shaft is not coupled to the plurality of speed-change gears.

Abstract: An automobile driving system includes an engine and a transmission. The transmission includes a variable gear ratio mechanism and a gear ratio of the transmission can be set to infinity. A one-way clutch is provided at an output portion of the transmission. At a time of a engine stopping controller controlling to stop the engine, a transmission-and-control device uses inertia from the engine up to an input member of the one-way clutch as assisting force for driving operations of the variable gear ratio mechanism to change the gear ratio at the transmission to infinity or close to infinity, before the engine actually stops.

Abstract: A method is described for controlling a clutch which is located between a drive motor and an automated manual transmission of a drive train. In this method, vibrations during load alternations are reduced by controlling the clutch so that a free-wheeling function is implemented during an engine braking mode.

Abstract: A power transmitting apparatus, such an automotive transmission, adapted to properly select transmission of or cutting-off of a driving force of the driving source to or from the wheels of a vehicle can include a torque converter having a torque amplifying function. A clutch mechanism can include a first clutch device configured to transmit the driving force to the wheels through the torque converter and a second clutch device configured to transmit the driving force without passing through the torque converter. A selecting device can control the first clutch device or the second clutch device in accordance with conditions of the vehicle including starting from a stop. An input-side measuring device can be used to measure an input-side rotational speed of the first clutch device and an output-side measuring device can be used for measuring an output-side rotational speed of the first clutch device.

Abstract: An overspeed system for a vehicle is disclosed. The overspeed system may have a power source, a transmission unit, and a torque converter assembly operatively coupling the power source to the transmission unit. The overspeed system may also have a travel speed sensor configured to generate a signal indicative of a vehicle speed, and a controller in communication with the torque converter assembly and the travel speed sensor. The controller may be configured to prevent a decoupling of the torque converter assembly in response to the signal.

Abstract: A method for controlling shift process in dual-clutch gearbox having dual-clutch gearbox input shaft connected to a drive engine, having two friction clutches and two partial gearboxes, comprising detecting demand for a shift from source gear into target gear, the source gear and target gear assigned to first partial gearbox; opening friction clutch assigned to first partial gearbox and closing friction clutch assigned to other partial gearbox to transmit drive power via intermediate gear of other partial gearbox; disengaging source gear and temporarily conducting a pressure-exertion process in friction clutch assigned to the first partial gearbox before engagement of target gear, with rotational speed of first partial gearbox being reduced due to the pressure-exerting operation according to drag torque, opening friction clutch assigned to other partial gearbox and closing friction clutch assigned to first partial gearbox to transfer drive power to the target gear without an interruption in tractive force.

Abstract: A transmission ECU calculates a differential rotation, which is the rotational speed difference between a friction plate and a separator plate, when it is determined that a second brake is not engaged. If it is determined that the differential rotation is equal to or above a predetermined value, the transmission ECU narrows the pack clearance of the second brake. If it is determined that the differential rotation is less than the predetermined value, the transmission ECU widens the pack clearance of the second brake.

Abstract: To alleviate a shift shock of an automatic transmission when a vehicle travels at a certain vehicle speed and a speed range is changed over to a drive range from a neutral range. When a neutral range is selected by a range selection lever, a neutral determination part outputs a determination signal Nt. When a vehicle speed V is equal to or more than a vehicle speed reference value Vref, a vehicle speed determination part outputs a signal VJ2. When the vehicle speed V is less than the vehicle speed reference value Vref, a signal VJ1 is outputted. The signal VJ1 is inputted to a shift map, and a hydraulic control unit determines a speed change stage base on the vehicle speed and a throttle opening degree. When a signal VJ2 is inputted to the hydraulic control unit, the shift stage is set at the neutral range.

Abstract: A method for the operation of an automatic transmission in a motor vehicle. The downshifting of the transmission takes advantage of a braking action of a driving motor connected to the automatic transmission through a clutch, are terminated by the closing of a clutch during a compression phase lasting until the achievement of a predetermined threshold speed. For the improvement of the immediacy of the vehicle drive after the termination of the compression phase, the invention provides that at speeds less than the threshold speed, downshifting is carried out and is terminated with an open clutch.

Abstract: A method of determining an application point of an automatically actuated clutch of an automatic mechanical transmission. After pre-selecting a new gear, the clutch automatically separates, the activated gear disengages, the engine rotational speed is brought to a target value for the new gear and the clutch, with higher advancing speed, is advanced to an application point at which the transmission input shaft is precisely entrained. To determine the application point, the gradient of the time curve of the rotational speed of the transmission input shaft is monitored, an important change of the gradient, that adjusts itself when reaching the application point, is determined and the current position of the clutch is defined as the application point. The application point is determined during downshifts, the time rotational speed curve of the transmission input shaft is between slowdown and re-acceleration, which is easily and accurately determined.

Abstract: A gear change control device for improving the stability of shift changes in a straddle-type vehicle. In response to an operation of a shift up switch or a shift down switch, the target angular position (?max(up), ?max(down), ?meet(up), ?meet(down), ?on(up), ?on(down)) and the rotational speed (vmax(up), vmax(down), vo(up), vo(down), v12(up)-v34(up), v21(down)-v43(down)) of a shift shaft are set based on a gear change command input signal inputted from the shift up switch or the shift down switch to a CPU. The shift shaft is rotationally driven at the set rotational speed until the set target rotational position is reached.

Abstract: A system and method for selectively engaging and disengaging auxiliary equipment to avoid gear clash in a vehicle is disclosed. The system includes a transmission, a transfer case, and a transmission controller. The transmission has a plurality of gears for establishing a plurality of gear ratios. The transfer case is coupled to the transmission by an output shaft. The transmission controller is in communication with a plurality of control devices for controlling the operation of the transmission. The controller includes control logic for controlling the engagement and disengagement of the auxiliary equipment.

Abstract: A method and system for executing a shift from a first fixed gear to a second fixed gear in a powertrain system comprising a two-mode, compound-split, electro-mechanical transmission operative to receive a speed input from an engine is described. It includes deactivating an off-going clutch, and generating a time-based profile for rotational speed of an oncoming clutch. The input speed is controlled based upon the rotational speed of the oncoming clutch and an output of the transmission. The oncoming clutch is actuated, preferably when the input speed is synchronized with a rotational speed of an output shaft of the transmission multiplied by a gear ratio of the second fixed gear, preferably after a predetermined elapsed period of time in the range of 500 milliseconds.

Abstract: A vehicle control system is comprised of a controller which is arranged to select an optimal mode adapted to a driving point of a vehicle from an optimal mode map of defining a plurality of running modes of the vehicle, to detect a generation of a mode transition in the optimal mode map, and to hold a current running mode selected before the transition for a holding time period when the generation of the mode transition is detected.

Abstract: A construction vehicle includes a control unit configured to shift gear after performing pre-shifting to couple a target speed-change gear that corresponds to a target speed with a target speed-change shaft in non-transmitting state of rotation of the input shaft when the gear shift is performed from a current speed to the target speed, in a state in which the current speed gear that corresponds to the current speed step and the current speed-change shaft that corresponds to the current speed gear are coupled. When the vehicle speed detected by the vehicle speed detecting section is zero, the control unit is configured to perform pre-shift auxiliary control prior to the pre-shifting control to input the rotation of the input shaft to the target speed-change shaft in a state in which the target speed-change shaft is not coupled to the plurality of speed-change gears.

Abstract: A device for controlling a power transmission device for a vehicle, which, at the time of gearshift, so controls the engine as to rotate at a target rotational speed, wherein at the time of shifting the gear up, a target value properly corresponding to an actual vehicle speed is set to quickly increase the engine output and to shorten the time for shifting the gear. In controlling the engine at the time of shifting the gear up, a target engine rotational speed is set based the signals from, wheel rotational speed detector means that detects the rotational speed of a wheel, such as an anti-lock control device. Thus, the target engine rotational speed is set depending properly upon an actual vehicle speed that varies accompanying an increase in the amount of engaging the clutch at the time of gearshift, and the gear at the time of accelerating the vehicle can be quickly shifted up without accompanied by the shift shock.

Abstract: A dynamic and event-dependent determination of a rest point of a clutch. The rest point being an actuation path shortly before a slipping region of the clutch in which the clutch still does not transmit an appreciable amount of torque but which allows very rapid attainment of a clutch position in which an appreciable torque can be transmitted. The rest point can be determined by proceeding from a basic test point by allowing for various offset or correction values. A control device determines, at favorable event-dependent times, these correction values depending on specific parameters. Then a clutch actuator is actuated such that the friction clutch is engaged up to this rest point. In this manner, increased wear of the clutch and the shifting time required to achieve the slipping region of the clutch can be minimized depending on the specific parameters.

Abstract: A control system of a vehicle including an engine and an automatic transmission operable to form one of a plurality of gear positions set according to running conditions of the vehicle, and a method of controlling the vehicle are provided. In the control, the rotational speed of an input-side rotary shaft of a shifting mechanism of the transmission is detected, and the vehicle is controlled so that, when an execution condition that one of the gear positions set according to the running conditions is maintained and the rotational speed of the input-side rotary shaft has increased to be higher than a rotational speed corresponding to the set gear position is satisfied, the vehicle is brought into running conditions that will eliminate a state in which air is present in the hydraulic fluid supplied from an oil supply device.

Abstract: A method controls a drivetrain of a motor vehicle having an internal combustion engine, an automatic transmission with at least two discrete transmission stages, and a clutch which is controlled automatically. The method is characterized in that when there is a transmission output speed at which the transmission input speed in an n-th transmission stage would be above a minimum rotational speed of the internal combustion engine and a transmission input speed in an (n+1)-th transmission stage would be below the minimum rotational speed, the drivetrain is operated in the (n+1)-th transmission stage with a slipping clutch and a rotational speed of the internal combustion engine which is above the minimum rotational speed. A control unit is configured to carry out such a method.

Abstract: A shift control device is provided for a vehicle transmission having first and second clutches arranged to be selectively engaged when one of gear ranges in first and second gear groups, respectively, is selected. The shift control device includes a rotational speed detecting section, a deceleration detecting section, a rotational speed estimating section, a gear determining section and a pre-shifting section. The rotational speed estimating section is configured to determine an estimated rotational speed of a drive source after downshifting based on a current rotational speed and a deceleration rate. The pre-shifting section is configured to control the vehicle transmission to achieve a waiting state before switching engagement states of the first and second clutches to obtain a next gear range when the next gear range is on a downshift side of a current gear range and the estimated rotational speed is lower than a first prescribed rotational speed.

Abstract: A shift transmission control device of a vehicle includes a transmission, a clutch, a shift transmission controller, and a shift inhibition state detector. The shift transmission controller is configured to control the transmission and the clutch. The shift inhibition state detector is configured to detect based on a running state of the vehicle that a predetermined shift inhibition condition is satisfied. The transmission is capable of providing a preliminary change gear ratio while the predetermined change gear ratio at which the rotational drive force is transmitted to the drive wheel is maintained. The shift transmission controller is configured to control the transmission to inhibit a change of the predetermined change gear ratio at which the rotational drive force is transmitted to the drive wheel and to provide the preliminary change gear ratio in response to the running state of the vehicle when the shift inhibition condition is satisfied.

Abstract: A vehicle including a transmission having a plurality of clutches for providing a plurality of speed ratios. A control module of the vehicle detects a possible tie-up of at least two of the clutches. Based on the detecting, the control module releases one of the possibly tied-up clutches. After the release, the control module determines whether a tie-up condition occurred. Based on the determining, the control module reapplies pressure to the released clutch. Loss of driver control of the vehicle thus can be prevented in the event of clutch tie-up.

Abstract: The instant invention relates to a method for determining an application point of an automatically actuated friction clutch of an automatic mechanical transmission for a motor vehicle. According to it, after the pre-selection of a new gear, the clutch automatically separates, the activated gear is disengaged, the engine rotational speed is brought to a target value for the new gear and the clutch with higher advancing speed is advanced to an application point at which the transmission input shaft is precisely entrained. To determine the application point, the gradient of the time curve of the rotational speed of the transmission input shaft is monitored, an important change of the gradient that adjusts itself when reaching the application point is determined and the position of the clutch existing at this moment is defined as application point.

Abstract: A method for launching a vehicle having an engine shaft, first and second transmission input shafts, first and second input clutches, a coupler, a power path, and an output, the method including engaging the coupler to connect the first input shaft and the first output shaft through the power path, engaging the second input clutch to connect the engine shaft and the second input shaft mutually, using a speed of the second input shaft to determine a desired clutch torque capacity of the first input clutch, and actuating the first input clutch to produce the desired clutch torque capacity of the first input clutch and to complete a drive connection between the first input shaft and the output.

Abstract: A method for controlling selection of an automatic transmission gear ratio with staged ratios or constant variation for a vehicle including a control for preventing/allowing extension of the gear ratio or for controlling a shortening the transmission gear ratio if, at a current engine speed, the power is insufficient for maintaining the vehicle speed. The method prevents extension of the transmission gear ratio if the power available after the extension is insufficient for maintaining the vehicle speed; otherwise allowing extension of the transmission gear ratio.

Abstract: An automatic transmission includes a planetary gear arrangement, and a plurality of engaging elements each arranged to vary an engagement state among the rotating elements of the planetary gear arrangement in such a manner to establish a normal gear ratio set and an emergency gear ratio set excluded from the normal gear ratio set. A control section of the automatic transmission performs the following: selecting a gear from the normal gear ratio set in accordance with a running state of a vehicle under normal operating conditions; controlling the engagement state of each of the engaging elements in such a manner to shift into the selected gear; detecting a failure in the engaging elements; selecting an escape gear ratio set from the normal gear ratio set and the emergency gear ratio set; and driving the vehicle with the escape gear ratio set when a failure is detected in the engaging elements.

Abstract: A control device for a vehicular power transmitting apparatus, having engaging devices including a one-way clutch, is disclosed which prevents a locked state of the one-way clutch from causing the occurrence of slippages of other engaging devices to avoid a drop in durability of the engaging device. To achieve this object, engaging a plurality of engaging devices in combined operations allows a plurality of gear positions to be established. A shifting mechanism (vehicular power transmitting apparatus) 10 is provided wherein at least one of the plural engaging devices includes a one-way clutch F1. The shifting mechanism switches a method of selecting a gear position at S3 depending on a shift position of a shift lever 52, determined at S1, and a vehicle running direction determined at S2.

Abstract: A method for adapting gear selection in a vehicle, the vehicle including an engine with an engine output shaft connected to an automated mechanical transmission via a clutch, a transmission output shaft connected to at least one driven wheel of the vehicle, an arrangement for registering whether a towed vehicle is connected to said vehicle, and at least one control unit for receiving input signals including signals indicative of the towed vehicle connection, and for processing the signals in accordance with programmed logic rules to issue gear selection command output signals to the transmission for gear shifting, where the control unit, when sensing that a towed vehicle has been connected to the vehicle, changes an originally selected first gear to a lower second gear having a higher starting gear ratio compared to the first gear. The towed vehicle connection registering arrangement registers at least bounce from when the vehicle bounces into the towed vehicle for connecting the towed vehicle to the vehicle.

Abstract: A gear change control device is provided for a straddle-type vehicle having a clutch and a transmission. The device includes a clutch actuator configured to engage and disengage the clutch. A transmission actuator is configured to change a gear of the transmission. At least one sensor is configured to sense an operational condition of the straddle type vehicle. At least one switch is configured to generate a gear change command. A controller is operatively connected to the clutch actuator, the transmission actuator, the at least one sensor, and the at least one switch. The controller is configured to change gears in response to the gear change command and during the gear change reengage the clutch under either a first control routine or second, different control routine based upon the operational condition of the straddle-type vehicle determined by the at least one sensor.

Abstract: An upshift control system for use in an automatic transmission including first and second friction elements, the upshift control system including a control unit that determines variation in an engagement capacity of the first friction element or an engagement capacity of the second friction element on the basis of combination of occurrence or non-occurrence of engine racing and compared lengths between a first time that elapses from output of a shift command to a start of an inertia phase and a second time that elapses from the out output of a shift command to a start of change in an actual gear ratio toward a target gear ratio to be achieved after the shifting, and performs a learning correction of a command pressure for the first friction element or a command pressure for the second friction element on the basis of the determination result.

Abstract: A method for the control of an actuator of a starting clutch of a motor vehicle. The actuator is so regulated by a control apparatus that the starting clutch is closed upon the presence of a desire for starting, as well as closed by an adjusted, transmission ratio, and the clutch is opened upon the termination of the starting procedure. For the freeing of a vehicle from a roadway obstruction by way of a rocking process of the vehicle, it is proposed that the starting clutch, during a starting procedure and by way of control of the actuation actuator, is operated in a fully automatic manner in such a way, that the torque (M_K) periodically varies.

Abstract: A continuously variable transmission for a motorcycle that provides appropriate engagement of a centrifugal clutch when a clutch shoe is worn. A control unit controls a change gear ratio to a TOP side to engage the centrifugal clutch when the centrifugal clutch is disengaged and an engine rotational speed is higher than a predetermined first rotational speed.

Abstract: An overspeed system for a vehicle is disclosed. The overspeed system may have a power source, a transmission unit, and a torque converter assembly operatively coupling the power source to the transmission unit. The overspeed system may also have a travel speed sensor configured to generate a signal indicative of a vehicle speed, and a controller in communication with the torque converter assembly and the travel speed sensor. The controller may be configured to prevent a decoupling of the torque converter assembly in response to the signal.

Abstract: A control valve arrangement having a clutch regulation valve (3), which pressurizes a device to actuate the clutch, and a valve that produces a controlled pilot pressure (P_VST3). An electronic control unit (ECU) controls a valve to supply a control valve with the pressure (P_VST3). The arrangement further having a hydraulic system which, if the ECU fails and the pressure (P_VST3) ceases, the last shift condition of the clutch actuation device, prior to the ECU failure, can be maintained in an emergency. The arrangement includes a valve, which delivers an activation pressure (P_A), depending on an engine-speed-dependent control pressure (P_D), to an actuation valve (2), which then delivers the pressure (P_A) to the valve (3) to prevent the emergency function initiation despite a lack of pressure (P_VST3) and existance of the pressure (P_D) sufficiently high to initiate the emergency function.

Abstract: The invention relates to a method and device for securely and comfortably operating a drive train of a motor vehicle, especially for operating a drive train with several clutches.

Abstract: In an automatic transmission control system and method, an electronic control unit is programmed to output a command to establish another gear stage different from the gear stage at the time of occurrence of fault-induced disengagement by combination of engagements of the friction elements other than the friction elements to be engaged at the time of occurrence of fault-induced disengagement, and simultaneously output a plurality of commands to establish a plurality of gear stages corresponding to combination of engagements of the friction elements to be engaged and disengaged, respectively, at the gear stage at the time of occurrence of fault-induced disengagement, when the gear stage at the time of occurrence of the fault-induced disengagement is a predetermined gear stage and the friction element undergoing the fault-induced disengagement is not determined.

Abstract: A method of reducing at least one of a contact speed and a transmitting torque between power transmission members, when a slack between the power transmission members in a power transmission path from a drive source to a wheel is apparently gone upon an acceleration or deceleration of the drive source or the wheel.