Abstract: A control device of a vehicle power transmission device for the vehicle power transmission device including a line pressure regulating device regulating a hydraulic pressure of a hydraulic fluid discharged from an oil pump to a predetermined line pressure while changing an opening area of a discharge flow passage, and an automatic transmission having a predetermined gear position established by engagement of a hydraulic friction engagement element by using the line pressure as a source pressure, the control device comprising: an abnormality determination portion configured to detect a slip of the hydraulic friction engagement element establishing the predetermined gear position at the time of establishment of the predetermined gear position and, if an input torque at the time of occurrence of the slip is equal to or greater than an abnormality determination value defined in advance based on a torque transmittable at a minimum line pressure by the hydraulic friction engagement element establishing the predeter

Abstract: A start control device and a start control method of a vehicular power transmission system including a lock-up clutch and a start clutch are provided in which start-time lock-up slip control is performed, and neutral control is performed. When the start-time lock-up slip control is additionally executed during cancellation of the neutral control, the gradient of an output rotational speed of the hydraulic power transmission which is changed, through engagement of the start clutch, toward an input rotational speed of the automatic transmission at the time of completion of engagement of the start clutch is controlled, using at least one of a start clutch pressure that is increased so as to engage the start clutch, and a lock-up clutch pressure that is increased so as to bring the lock-up clutch into slip engagement.

Abstract: The embodiments herein provide an automatic clutch system for automobiles. The system comprises a mechanical section and an electronic section. The mechanical section comprises a rail support base with a rail-shaped ridge installed, dynamic parts installed on the rail-shaped ridge, supporting arms, an elevator mechanism connected to the clutch pedal and a clutch pedal lever. The electronic section comprises an input section for placing the elevator mechanism in due place and a keyboard for regulation, a sensor circuit, a command circuit including microcontroller, an exit section for changing a position of the elevator mechanism, a feedback circuit including a rotary encoder and monitors. The command circuit processes an instruction data from the input resources based on the regulations set by the user and transmits a command to the output section to position the elevator mechanism.

Abstract: A lock-up control apparatus includes a kick-down instruction detector configured to detect a kick-down shift transmission instruction during application of a lock-up clutch. A first lock-up control amount changer is configured to change the lock-up control amount when the kick-down shift transmission instruction is detected. An intermediate gear speed determinator is configured to determine whether the kick-down shift transmission instruction includes an intermediate gear speed shift transmission instruction to an intermediate shift transmission gear speed. A second lock-up control amount changer is configured to change the lock-up control amount when the kick-down shift transmission instruction includes the intermediate gear speed shift transmission instruction. A target gear speed shift transmission instruction detector is configured to detect a target gear speed shift transmission instruction.

Abstract: A power transmitting apparatus configured to improve vehicle starting performance using the torque amplifying function of a torque converter, improve power transmitting efficiency during steady vehicle operation and reduce size of the power transmitting apparatus. A power transmitting apparatus configured to transmit power from a driving source of a vehicle to its wheels configured to selectively transmit/cut-off driving force to the wheels comprises a torque converter having a torque amplifying function. A clutch mechanism includes a first clutch to transmit the driving force to the wheels through a power transmitting system of the torque converter and a second clutch to transmit the driving force without the power transmitting system of the torque converter. A selecting device controls the first/second clutch per the conditions of the vehicle. A planetary gear configured to select the power transmission pathway during forward operation and switch the power transmission pathway during reverse operation.

Abstract: A method for actuating a clutch in the drive train of a motor vehicle, including: generating a respective position setpoint for each predetermined target interval to actuate the clutch; in each predetermined target interval, actuating the clutch in a plurality of predetermined controller sampling intervals; discretizing a respective position setpoint change into a plurality of intermediate position setpoints; determining a number of intermediate position setpoints in the plurality of intermediate position setpoint depending on the ratio of the target interval to the controller sampling interval; and specifying the respective position setpoint changes in steps to actuate the clutch.

Abstract: A hydraulic control device for an automatic transmission that prevents the introduction of foreign materials from a starter into the lubricant path and also reduces duct resistance at a non-lockup time when the oil temperature is low. Oil is provided to an oil cooler for cooling the oil, and is also provided to the automatic transmission for lubricating the transmission. The device includes a switching valve that is switched between a lockup state and a non-lockup state of the clutch. In the lockup state, the switching valve is switched to a first position at which a first input pressure is supplied to the starter and a second input pressure is supplied through the oil cooler to the transmission. In the non-lockup state, the switching valve is switched to a second position at which the first input pressure is discharged through the starter and the oil cooler to an oil pan, and the second input pressure is supplied to the transmission.

Abstract: A controller has a command section, a control section, a time measurement section, and a command fixing section. The command section generates a command regarding the actuation state of a lock-up clutch in accordance with a condition value that is determined by the accelerator operating amount and the vehicle speed. The time measurement section starts to measure time when the accelerator operating amount drops to 0 with the current condition value maintained in a hysteresis range and the command section generates the acceleration slip executing command. When the accelerator operating amount is increased from 0, the time measurement section stops the measurement of time and resets the measured time to 0. The command fixing section fixes the command of the command section as an acceleration slip executing command in the period from when the time measurement by the time measurement section has started to when the measured time reaches a determination value.

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 hydraulic controller of a power transmission device is equipped with a transmission for changing a rotation speed of motor power input from a motor and outputting the motor power; a forward/backward change-over mechanism provided between an input shaft, where the motor power of the motor is input and the transmission; and a torque converter having a direct coupling mechanism for transmitting the motor power between an output shaft and the input shaft of the motor; a solenoid valve for adjusting an original pressure and generating a control pressure; and a change-over element for changing over a hydraulic pressure supplied to the forward/backward change-over mechanism so as to become a low pressure during deceleration driving when the direct coupling mechanism is controlled by the solenoid valve, wherein any one of engagement states of the forward/backward change-over mechanism and the direct coupling mechanism is controlled by the control pressure.

Abstract: A control method of a lockup clutch includes eliminating a loss stroke of a piston by a pre-charge of a supplied hydraulic pressure, increasing a force applied to the piston by further supply of the hydraulic pressure after the pre-charge, controlling a slip rotation speed between a pump impeller and a turbine runner in a torque converter connected to an automatic transmission, and determining a time for performing the pre-charge when a shift stage of the automatic transmission is under a neutral state and a vehicle is substantially stopped.

Abstract: A lock-up control apparatus for an automatic transmission in which operations of four engagement elements are required when shifting is performed from a first shift speed to a second shift speed, the first shift speed being achieved by engagement of a first engagement element and a second engagement element, the second shift speed being achieved by engagement of a third engagement element and a fourth engagement element. The lock-up control apparatus includes a lock-up control unit that performs a control for bringing a lock-up clutch into one of a disengagement state and a slip state at a start of shifting, and that prevents reengagement of the lock-up clutch at a completion of engagement of the third engagement element when shifting is performed from the first shift speed to the second shift speed during lock up.

Abstract: A control method of a lockup clutch includes eliminating a loss stroke of a piston by a pre-charge of a supplied hydraulic pressure, increasing a force applied to the piston by further supply of the hydraulic pressure after the pre-charge, controlling a slip rotation speed between a pump impeller and a turbine runner in a torque converter connected to an automatic transmission, and determining a time for performing the pre-charge when a shift stage of the automatic transmission is under a neutral state and a vehicle is substantially stopped.

Abstract: A lock-up control apparatus for an automatic transmission in which operations of four engagement elements are required when shifting is performed from a first shift speed to a second shift speed, the first shift speed being achieved by engagement of a first engagement element and a second engagement element, the second shift speed being achieved by engagement of a third engagement element and a fourth engagement element. The lock-up control apparatus includes a lock-up control unit that performs a control for bringing a lock-up clutch into one of a disengagement state and a slip state at a start of shifting, and that prevents reengagement of the lock-up clutch at a completion of engagement of the third engagement element when shifting is performed from the first shift speed to the second shift speed during lock up.

Abstract: An automatic transmission and method including a plurality of hydraulic servos which respectively engage and disengage a plurality of frictional engagement elements, a first solenoid valve for gear shifting which is used for generating a hydraulic pressure supplied to a predetermined hydraulic servo, a second solenoid valve for lock-up which is used for generating a hydraulic pressure supplied to a fluid transmission apparatus for executing a lock-up, a hydraulic control apparatus, a first connector which connects the first solenoid valve and the hydraulic control apparatus, a second connector which connects the second solenoid valve and the hydraulic control apparatus, a failsafe mechanism which achieves a predetermined shift range in a high-speed-side when the first connector is disconnected and a gear shift processing mechanism which achieves a predetermined shift range among a plurality of shift ranges when the second connector is disconnected.

Abstract: An apparatus for controlling a power transmission device, having a lockup shift valve that changes the operating state and non-operating state of the lockup mechanism, and a regulator valve that is capable of changing the pressure (line pressure) of working oil used to operate a speed changer CVT between a low pressure and a high pressure, wherein changeover between a mode, where the lockup mechanism is operated and the line pressure is set to a low pressure, and a mode, where the lockup mechanism is not operated and the line pressure is set to a high pressure, is carried out by changing the output of ON and OFF signals from the first solenoid valve.

Abstract: A control unit controls a lockup duty ratio to be maintained at a first duty ratio, which is the minimum value within such a range as not to slip a lockup clutch, during a period of time since a decision is made to perform a shifting operation until an actual shifting operation is started. The control unit then lowers the lockup duty ratio to a corrected (learned) second duty ratio and gradually lowers the lockup duty ratio from the second duty ratio at a predetermined rate of change so that a slip revolutionary speed can be equal to a target slip revolutionary speed when the shifting operation is finished. Alternatively, the control unit corrects the rate of change while maintaining the second duty ratio at a uniform value so that the slip revolutionary speed can be equal to the target slip revolutionary speed when the shifting operation is finished.

Abstract: A hydraulic pressure control system for an automatic transmission is capable of reducing the size and simplifying the structure of a lockup controlling hydraulic circuit. An oil pressure output from a solenoid valve acts on an oil pressure chamber. The internal pressure of another oil pressure chamber becomes high only in a forward low-speed range and becomes low in all of the other gear shift ranges. The internal pressure of another oil pressure chamber becomes high only in forward ranges and becomes low in neutral and reverse ranges. The valve member moves in accordance with oil pressures applied to the oil pressure chambers to change over oil paths connected to a clutch control oil chamber and a torque converter oil chamber, whereby a lockup clutch assumes one of engaged, slip, and released states.

Abstract: A control apparatus for a hydraulically operated transmission for a vehicle has a control circuit portion for a lockup clutch and a solenoid valve for controlling a clutch which is engaged in a particular drive range. In another drive range in which the clutch is not engaged, an output pressure of the solenoid valve is inputted to the control circuit portion. A changeover valve can be switched between a first position in which a first oil passage to be connected to an output side of the solenoid valve in the drive range and a second oil passage to be communicated with the control circuit portion are brought into communication with each other, and a second position in which this communication is shut off. The changeover valve is switched to the first position by a hydraulic oil pressure which is generated at the time of establishing a predetermined transmission train other than the first-speed transmission train.

Abstract: Electronic and hydraulic control system of an automatic transmission for automotive vehicle and method for controlling hydraulic pressure whereby line hydraulic pressure can be compensated. A hydraulic pressure state within the electronic and hydraulic control system is precisely detected and the signal of this detected hydraulic pressure is transmitted to a transmission control unit such that the malfunction of the valves and the correct gear shifting stage can be determined. Since the hydraulic pressure state can be detected to be compensated by the control of the TCU, such that the shift quality can be improved.

Abstract: An electronically controlled multiply ratio transmission for an automotive vehicle powertrain having a hydrokinetic torque converter with a bypass clutch, solenoid operated shift valves under the control of an electronic microprocessor that receives signals from an output shaft speed sensor, an engine speed sensor, a driver controlled drive range selector position, an engine throttle position sensor, and other powertrain operating variables, the bypass clutch having a controlled slip characteristic.

Abstract: A control system for a torque converter includes a lock-up clutch provided in the torque converter for connecting input and output members of the torque converter directly, and a shift valve having first and second spools disposed in series in a sleeve for shifting an introduction of an engaging and releasing pressure acting on the lock-up clutch in accordance with positions of the first and second spools. The first spool is subjected to a first hydraulic pressure at one end thereof. The second spool is subjected to a second hydraulic pressure at one end thereof opposite to the one end of the first spool. The first and second spools are subjected to a third hydraulic pressure therebetween. The control system further has a first control device for controlling the first hydraulic pressure, and an adjusting valve for controlling the releasing pressure of the lock-up clutch.

Abstract: A continuously variable belt drive transmission has a torque converter with a lockup clutch. The lockup clutch is engaged in accordance with driving conditions of the torque converter. Quantity of downshifting the transmission is decided in dependency on changing rate of speed of an input member of the transmission so that the speed of the input member coincides with speed of the engine. The transmission is downshifted by the downshift quantity and the lockup clutch is engaged so as to change the engine speed at a substantially constant rate.

Abstract: A slip control device of a fluid coupling is mounted in an automatic transmission of the type having a lockup clutch for directly coupling the input side and the output side of the fluid coupling to each other and a hydraulic control circuit for adjusting the locking force of the lockup clutch so as to make the slip of the lockup clutch controllable. The slip control device includes an electric control unit for controlling the hydraulic control circuit so that the locking force of the lockup clutch is set to a predetermined value intermediate between a value corresponding to a complete lockup condition and a value corresponding to a complete release condition during a predetermined period of time. Upon lapse of the predetermined period of time, the locking force of the lockup clutch is reduced temporarily and then increased gradually.

Abstract: A hydraulic control apparatus for a vehicle power transmitting system having a fluid coupling equipped with a lock-up clutch, and a transmission to which power is transmitted from an engine of the vehicle through the fluid coupling. The fluid coupling has an engaging chamber and a releasing chamber for engaging and releasing the lock-up clutch. The apparatus includes a discharge passage communicating with the engaging chamber, for normally draining the engaging chamber to a drain, to thereby normally release the lock-up clutch, and a rapid release valve connected to the discharge passage. The rapid release valve operates to by-pass the discharge passage to the drain therethrough, for thereby rapidly draining the engaging chamber to rapidly release the lock-up clutch. A lock-up pressure regulating valve is provided for regulating a lock-up clutch pressure applied to the fluid coupling, normally to a first value, and upon operation of the rapid release valve, to a second value higher than the first value.

Abstract: A lockup torque converter of an automatic transmission for an automotive vehicle consists of an impeller connected to an engine, a turbine connected to the automatic transmission, and a lockup clutch disposed between first and second pressure chambers formed in a housing of said lockup torque converter for locking and releasing the lockup torque converter. A control unit supplies a hydraulic pressure into the first pressure chamber and withdraw a hydraulic pressure chamber from the second pressure chamber or reversely so as to actuate the lockup clutch to lock or unlock the lockup torque converter, respectively. A pressure regulating unit develops a pressure difference between the first and second pressure chambers when the shifting of the automatic transmission is detected, thereby causing the lockup clutch to allow the lockup torque converter to slip in accordance with certain conditions.

Abstract: The torque capacity of a torque converter clutch is controlled with a two-state directional valve and a single solenoid operated pressure control valve. In operation, the directional valve is spring biased to a release state in which converter feed pressure is directed to a passage between the clutch plate and the converter input shell to release the clutch and feed the converter. The return fluid from the opposite (apply side) of the clutch is routed through the directional valve to a low pressure fluid cooler. A control pressure generated by the solenoid operated valve develops a hydraulic bias which opposes the spring bias. When the hydraulic bias is sufficiently great, the directional valve shifts to a control state in which the solenoid operated valve controls the pressure supplied to either the apply or release side of the clutch to control its torque capacity.

Abstract: A method of determining and controlling a lock-up of a torque converter in a four-speed automatic transmission for full or partial frictional coupling between the torque converter and the vehicle engine. The method includes the steps of checking conditions that preclude partial lock-up operation and unlocking the torque converter if partial frictional coupling is precluded. The method also includes setting initial conditions for going from unlock to partial frictional coupling and checking for conditions that allow full frictional coupling operation. The method further includes fully frictional coupling the torque converter if conditions allow full frictional coupling operation, otherwise, partially frictionally coupling the torque converter.

Abstract: A control system for a torque converter includes a lock-up clutch provided in a torque converter for connecting an input member and an output member of the torque converter directly. An engaging and disengaging hydraulic device controls an engaging and disengaging action of the lock-up clutch. A shift valve provided with a first and second spools in series controls introduction of a driving hydraulic pressure into the hydraulic device. The first spool of the shift valve is subjected to a first hydraulic pressure at one end, while the second spool is subjected to a second hydraulic pressure at the other end. The first and second spools are subjected to a third hydraulic pressure therebetween.

Abstract: A system for controlling a lock-up clutch of a torque converter comprises a lock-up control valve, and a shuttle valve. The lock-up control valve includes a spool having a first and a second pressure acting areas. The shuttle valve delivers an output hydraulic pressure when at least one of two inlet ports is pressurized. One of the inlet ports is subject to a first hydraulic pressure which builds up at a band brake during operation with the fourth speed ratio, while the other inlet port is subject to a second hydraulic pressure which builds up at an overrun clutch during operation with the third, second, and first speed ratios when an engine brake operation range is selected. The output hydraulic pressure of the shuttle valve is transmitted to the lock-up control valve to act on the second pressure acting area. The first pressure acting area is subject to a third hydraulic pressure which builds up at a high clutch during operation with each of the third and fourth speed ratios.