Abstract: A lock-up clutch is arranged in parallel with a power transmission path between a pump impeller and a turbine runner of a fluid coupling arranged between the drive side and the load side, wherein the lock-up clutch changes the power transmission path. A stall capacity factor is determined using an engine speed at which the maximum engine torque on the drive side is generated, and the rotation on the drive side is transmitted to the load side by using the stall capacity factor. Therefore, optimal acceleration can be obtained by setting the stall capacity factor such that the stall rotational speed is in the vicinity of the rotational speed at which the maximum engine torque is generated. Thus, drivability can be improved by obtaining a control amount with which the vehicle speed responds as expected to the accelerator, there is no uncomfortable sensation, and fuel economy can be improved.

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 lock-up clutch control device which controls a lock-up clutch (6) provided in a torque converter (5) interposed between an engine (3) and a transmission (4) used with a vehicle, is disclosed. The lock-up clutch control device has a differential pressure generating device (7,8), a vehicle speed sensor (13), a throttle valve opening sensor (14), an transmission input shaft rotation speed sensor (16), engine torque detection means (2), and a controller (1). The controller (1) determines, based on the detected vehicle speed (VSP) and the detected throttle valve opening (TVO), whether or not a control region of a torque converter is a converter region wherein control is performed to disengage the lock-up clutch.

Abstract: A lock-up clutch control device controls a lock-up clutch provided in a torque converter mounted between an engine and a transmission of a vehicle. The lock-up clutch control device switches between a converter state and a lock-up state by controlling a differential pressure supplied to the lock-up clutch. The lock-up clutch control device has a controller and a differential pressure generator for generating the differential pressure in response to a differential pressure command value. The controller calculates a first differential pressure command value which decreases at a predetermined rate, after the vehicle speed becomes a first predetermined speed; sets the differential pressure command value to a second differential pressure command value, before the vehicle speed becomes a second predetermined speed; and sets the differential pressure command value to a value at which the lock-up clutch is immediately released, when the vehicle speed becomes the second predetermined speed.

Abstract: A vehicle speed memory unit stores a vehicle speed at a prior predetermined time, the vehicle speed being calculated from an interval of the vehicle speed pulse. A first rapid deceleration detecting section compares an elapsed time from a time the vehicle speed pulse signal is inputted, measured by an elapsed time measuring unit, with a pulse interval corresponding to a predetermined deceleration relative to a vehicle speed stored by the vehicle speed memory unit, or a second rapid deceleration detecting section calculates an undetermined vehicle speed from the elapsed time measured by the elapsed time measuring unit, and calculates a deceleration from the undetermined vehicle speed and the vehicle speed at the prior predetermined time, and compares the calculated deceleration with a predetermined deceleration threshold value. Thus, rapid vehicle deceleration can immediately be determined at the present time without waiting for the determination of the vehicle speed after input of the next pulse signal.

Abstract: A transmission apparatus (416) is provided that is configured to transmit energy from a power source to a work device. Transmission apparatus (416) includes an input shaft (426) adapted to receive energy from the power source and an output shaft (434) adapted to transfer energy to the work device. Preferably, transmission apparatus (416) further includes a fluid coupling (25) configured to transfer energy from input shaft (426) to output shaft (434) and a mechanical coupling (24) configured to transfer energy from input shaft (426) to the output shaft (434).

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 fluid coupling transmits power from a drive side to a driven side by utilizing kinetic energy of fluid such as oil. The fluid coupling comprises a pump impeller (4) provided on a drive shaft (1), a turbine impeller (5) provided on a driven shaft (9), a housing (20) fixed to the pump impeller (4) and surrounding the turbine impeller, and a multiple disc clutch provided between a drive shaft side and a driven shaft side. The multiple disc clutch is operated to couple the drive shaft (1) and the driven shaft (9) mechanically so that the drive shaft and the driven shaft are rotated at the same rotational speed. Thus, the fluid coupling can improve a power transmitting efficiency because of no slip between the rotational speed of the drive shaft and the rotational speed of the driven shaft.

Abstract: A method for operating a clutch (10), whose clutch slip (s) is adjusted to a setpoint value (s0) with the aid of a manipulated variable, should allow a clutch to be controlled in a particularly reliable and stable manner. To this end, the present invention provides for a slip value only being permitted to be a setpoint value (s0), when the derivative of the friction coefficient/slip characteristic at this slip value exceeds a specifiable limiting value. In particular, the setpoint value (s0) is selected as a function of a number of operating parameters, inside a range of permissible setpoint values (s0); the slip value, at which the derivative of the friction coefficient/slip characteristic falls below a specifiable limiting value, being selected as an upper limit (G) of the range of permissible setpoint values (s0).

Abstract: A lockup clutch for a torque converter includes a pump extension, a receiving plate connected to the pump extension defining a hydraulic pressure chamber communicating with a portion between a pump impeller and a turbine impeller, a pressing plate opposed to the receiving plate for movement toward and away from the receiving plate, an annular friction clutch plate interposed between the receiving plate and the pressing plate and connected to the turbine impeller, a return spring for biasing the pressing plate in a retracting direction, and an escape bore permitting the inside and outside of the receiving plate to communicate with each other on the side of an inner periphery of the friction clutch plate. When the rotational speed of the pump impeller is increased to a value equal to or higher than a predetermined value, the pressing plate clamps the friction clutch plate in cooperation with the receiving plate under the action of a centrifugal hydraulic pressure within the hydraulic pressure chamber.

Abstract: The invention relates to a hydrodynamic clutch (1) comprising at least two impellers, as outer wheel (3), and an inner wheel (3). The inner wheel is equipped with an integrated synchronizer clutch (2) and is enclosed by a clutch shell (4) that is coupled to said outer wheel. The invention is characterized in that the clutch elements (6.1, 6.2) are formed by the inner wheel and by the clutch shell. Said inner wheel comprises at least two segments (8.1, 8.2, 8.3) that are displaceably mounted in a radial direction.

Abstract: A gear transmission for keeping a load in balance at both ends of a crank shaft in an all-terrain saddle type vehicle provided with a transmitting unit capable of transmitting power from the crank shaft to the gear transmission and a generator connected to the crank shaft. A torque converter is provided with a lock-up clutch mounted on the crank case side of the torque converter and capable of directly connecting a pump to a turbine. A driving gear fixed to the turbine and capable of transmitting the output of the torque converter to the gear transmission is mounted on one end side of a crank shaft outside the crank case such that the lock-up clutch is sandwiched between the torque converter and the driving gear. A generator is mounted on the other end side of the crank shaft outside the crank case.

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

Abstract: In a transmitting system for a small-sized vehicle in which a crankshaft of an engine and an input shaft of a multi-stage transmission are connected to each other through a fluid transmitting device, a shifting clutch is interposed between the crankshaft of the engine and the multi-stage transmission in a series relation to the fluid transmitting device. A lock-up clutch is interposed between a pump impeller and a turbine impeller of the fluid transmitting device. Thus, when the multi-stage transmission is to be shifted, the shifting operation can be conducted lightly, in spite of a creep phenomenon of the fluid transmitting device, by bringing the shifting clutch into an OFF state. Moreover, during cruising of the vehicle, the slipping of the fluid transmitting device can be inhibited by the OFF state of the lock-up clutch to enhance the transmitting efficiency.

Abstract: The housing of a hydrokinetic torque converter in the power train between the engine and the transmission of a motor vehicle contains a lockup valve which can be engaged to transmit torque directly from the output element of the engine to the output member of the turbine in the housing. Engagement of the lockup clutch at a relatively low RPM of the engine and/or under certain other circumstances is prevented or minimized by the provision of one or more valves which are designed to establish or to at least partially seal one or more paths for direct flow of hydraulic fluid between two compartments forming part of a chamber in the housing of the torque converter and being disposed at opposite sides of the axially movable piston of the lockup clutch. The valve or valves can be designed to react in response to changing RPM of the housing of the torque converter, in response to changes of the temperature of hydraulic fluid in the housing and/or in response to changes of the viscosity of such fluid.

Abstract: A lock-up control device is provided to control the engaging and release of a lock-up clutch, which is arranged in parallel with a torque converter to transmit driving force of an engine of a car. Herein, target driving force is calculated based on accelerator pedal opening and car velocity. A present shift position is detected using a shift map based on accelerator pedal opening, car velocity and engine speed. Target engine torque is calculated based on the target driving force and present shift position as well as a torque amplification ratio, which is detected when the torque converter is placed in a torque amplification state. A lock-up release instruction is issued under conditions that the torque converter is placed in the torque amplification state while the target engine torque is greater than a preset value, which is determined in advance based on a torque characteristic of the engine.

Abstract: An adaptive control system and method for direct clutch engagement control for an automatic transmission including a micro-controller that receives and stores input data from driveline sensors and executes transmission clutch control logic. The micro-controller develops output signals in real time and transfers the signals to a driver circuit that controls solenoids that enable clutch engagement. The signals for establishing clutch pressure buildup are delivered to a driver circuit that produces hydraulic pressure at the clutch to achieve a smooth torque and speed transition for the torque input elements of the transmission. Adaptive pressure values are stored in a keep-alive memory. The pressure values are adjusted values based on the result of previous engagements. This compensates for driveline variables such as changes in coefficients of friction, spring loads, clutch wear, etc.

Abstract: An apparatus for responding to failure of a secondary load driven by a primary mover includes at least one sensor sensing a rotational parameter of the secondary load and an electronic control module for (1) disengaging the secondary load from the primary mover and subsequently re-engaging it when the sensed rotational parameter indicates a first range of slip, (2) disengaging the secondary load from the primary mover when the sensed rotational parameter indicates a second range of slip, and (3) deactivating the primary mover when said sensed rotational parameter indicates a third range of slip.

Abstract: A slip control system for a torque converter with a lockup clutch comprises a controller that outputs a slip control signal to a slip control actuator of the lockup clutch to adjust an actual slip rotation speed of the torque converter at a target slip rotation speed. The controller is coupled to sensors for detecting information indicative of a condition of a drive system including the torque converter. The controller decides an operating state of the torque converter at time when the slip control is started, and selects one of initial valves for a slip command signal corresponding to the slip control signal according to the decided operating state of the torque converter at the start of the slip control. This arrangement functions to prevent troubles including shocks due to shortage of slippage in the torque converter and generation of radial slippage of the torque convert from generating at a time staring the slip control.