Abstract: A torque transfer mechanism includes a multi-plate clutch assembly that is operably disposed between a first rotary and a second rotary member. A control system determines a desired quantity of torque to deliver to the second rotary member and controls the clutch to produce the desired torque.

Abstract: A lube pump is provided for supplying lubricant to various components of a power transmission unit of the type used in motor vehicles. The lube pump includes a pump assembly and a coupling mechanism for releaseably coupling the pump assembly to a driven shaft. The coupling is operable to release the pump assembly when the rotary speed of the shaft exceeds a threshold value.

Abstract: A method for the readjustment of an actuator of an all-wheel drive clutch of a motor vehicle that includes determining a clutch slip value corresponding to a difference between the speed of a primary axle and the speed of a secondary axle; determining a reference secondary axle torque corresponding to the proportion of a driving torque which is transmitted to the secondary axle and for which a clutch slip value of substantially zero is expected; and comparing the clutch slip value with a threshold value and comparing a desired clutch torque with the reference secondary axle torque. A desired clutch torque/control signal relationship for the clutch actuator is changed in dependence on the result of these comparisons.

Abstract: A clutch arrangement responsive to a speed difference including an input element and an output element that are rotatable relevant to one another, a friction clutch, and a pump. The friction clutch couples the input element with the output element in dependence on a hydraulic pressure prevails in a pressure space of the clutch arrangement. The pump has a first pump part that is rotationally fixedly connected to the input element and a second pump part that is rotationally fixedly connected to the output element. The pump may be driven by a rotary movement of the input element and the output element relative to one another, with a pressure side of the pump being connected to the pressure space. An orifice having a substantially temperature independent leakage characteristic is arranged at a leakage line that leads from the pressure space to a low pressure space and extends parallel to the pump.

Abstract: A method controlling a clutch arrangement that serves, in a powertrain of a motor vehicle, for the transmission of a torque from an input element to an output element. Starting from an activated state of the clutch arrangement, a respective estimated torque value is calculated in repeating calculation cycles. A torque build-up value is calculated in dependence on at least one speed difference value. A torque reduction value is calculated in dependence on at least the last calculated estimated torque value. The estimated torque value is re-calculated on the basis of the last calculated estimated torque value by up integration of the calculated torque build-up value and down integration of the calculated torque reduction value. The recalculated estimated torque value is compared with a torque threshold value. The clutch arrangement is deactivated when the recalculated estimated torque value is below the torque threshold value.

Abstract: A drive axle assembly includes first and second axleshafts and a drive mechanism coupling a driven input shaft to the axleshafts. The drive mechanism includes a differential assembly, a planetary gear assembly operably disposed between the differential assembly and the first axleshafts, a transfer clutch and first and second brakes. The first brake is operable with the transfer clutch and the planetary gear assembly to increase the rotary speed of the first axleshaft which, in turn, causes a corresponding decrease in the rotary speed of the second axleshaft. The second brake is operable with the transfer clutch and the planetary gear assembly to decrease the rotary speed of the first axleshaft so as to cause an increase in the rotary speed of the second axleshaft. A control system controls actuation of both brakes and the transfer clutch.

Abstract: A transfer case for a motor vehicle having an input shaft, a first output shaft, a second output shaft, a clutch, a transfer mechanism, a sensor portion and a magnetoelastic torque sensor. The clutch has a clutch pack and a thrust mechanism that is configured to exert an engagement force on the clutch pack. The clutch pack has a first portion, which is rotatably driven by either or both of the input shaft and the first output shaft, and a second portion that is supported for rotation relative to the first portion. The transfer mechanism couples the second portion of the clutch pack to the second output shaft. The sensor portion is coupled to the first or second output shaft and is at least partially formed of a magnetoelastic material. The magnetoelastic torque sensor is disposed about and radially in-line with the sensor portion.

Abstract: A dual-clutch powershift transmission for use in a motor vehicle having an engine and a driveline includes an output shaft adapted for connection to the driveline, first and second input shafts, a first engine clutch operable for establishing a releaseable drive connection between the engine and the first input shaft and a second engine clutch operable for establishing a releasable drive connection between the engine shaft and the second input shaft. A first constant-mesh gearset is driven by the first input shaft. A second constant-mesh gearset is driven by the second input shaft. A first shift clutch releasably engages the first gearset to establish a drive connection between the first input shaft and the output shaft. A second shift clutch releasably engages the second gearset to establish a drive connection between the second input shaft and the output shaft.

Abstract: The invention relates to a friction clutch having a single-acting actuator which is a piston-cylinder unit and is connected in a controllable fashion to a pressurized fluid source. In order to be able to carry out a fast pilot stroke up to the point at which the clutch makes contact, the piston-cylinder unit has a stepped piston whose first step of small diameter delimits, by means of its cylinder, a first pressure space, and whose second step of relatively large diameter delimits, by means of its cylinder, a second pressure space, a pressure line being connected to the first pressure space and, by means of a first non-return valve which opens at a certain pressure, to the second pressure space, and it also being possible for the second pressure space to be connected via a discharge line and a suction line, which contains a second non-return valve, to the fluid reservoir. The invention also relates to a drive device having clutches of said type.

Abstract: The present invention relates to a magnetorheological clutch including a primary part, a secondary part and a magnet for the generation of a magnetic field. The primary part and the secondary part are rotatable relative to one another around an axis of rotation of the clutch, with the primary part being rotationally fixedly connected to at least one disk. The disk is surrounded by coupling gaps in which a magnetorheological medium is arranged. The thickness of the at least one disk along the coupling gap has a value of approximately 0.4 mm to approximately 1 mm, with the at least one disk being formed along the coupling gaps without material interruptions.

Abstract: A magnetorheological clutch consists of a stationary part, a primary part and a secondary part, a working space which contains a magnetorheological fluid being formed between primary part and secondary part, in which working space primary discs and secondary discs successively alternate in the radial direction, and a controllable magnetic field acting on the magnetorheological fluid. In order to prevent segregation of the fluid by centrifugal force in a simple type of construction, the working space is L-shaped in longitudinal section, the primary part is a shaft and the secondary part is a pot enclosing the working space, and are of pot-shaped design.

Abstract: A manual helical planetary transmission comprises a housing, a sun gear, a planet carrier with helical planetary gears and an axially displaceable ring gear which can be coupled to the housing or to the planet carrier. The transmission provides a compact and easy-to-produce solution for locking the gears. For this purpose, first saw-tooth coupling teeth are provided on both sides of the fronts of the ring gear and have a gently sloping first profile. Second saw-tooth coupling teeth provided on the housing and the planet carrier have a gently sloping profile and fit into the first coupling teeth. In the respective gear, the peripheral forces acting upon the ring gear force the gently sloping first profiles of the first coupling teeth against the gently sloping first profiles of the second coupling teeth on the housing or the planet carrier, thereby frictionally keeping the ring gear in the respective engaged position.

Abstract: A pump assembly includes a pump housing, a stator ring supported within the pump housing, and a pump ring also rotatably supported within the pump housing. The pump ring interfaces with the stator ring to define a plurality of variable volume pressure chambers. A cover plate covers the stator ring and pumping ring within the pump housing. The cover plate is axially displaceable relative to the pump housing and defines a wall of each of the pressure chambers. Pressure within the pressure chambers induces linear movement of the cover plate away from the stator ring and the pump ring.

Abstract: A method and apparatus for the setting of the torque transmitted by a friction clutch by means of an actuator chain having an electric motor which effects a displacement of a pressure plate of the friction clutch via a reduction gear and a mechanism for the conversion of the rotary movement of the electric motor. In the method, on the basis of a given torque/angle dependence, a desired angle of rotation of the electric motor or of a link of the actuator chain is determined from the torque to be transmitted by the friction clutch and is set in a setting process by means of a regulator acting on the electric 2.

Abstract: A method and control apparatus for the generation of a setting signal for an actuator of a clutch unit of a motor vehicle with which the torque to be transmitted by the clutch unit can be set. A desired value for the torque to be transmitted is determined by a main control unit in dependence on predetermined first parameters. A setting signal for the actuator corresponding to the desired value is generated by an additional control unit on the basis of the determined desired value. A desired value tolerance range for the determined desired value of the torque is determined by the main control unit in dependence on predetermined second parameters. The desired value tolerance range is transmitted to the additional control unit, with the additional control unit determining an actual value of the torque transmitted or transmissible by the clutch unit and generating a new setting signal for the actuator when the actual value is outside the desired value tolerance range.

Abstract: A multi-disk clutch having a plurality of interengaging disks movable along a longitudinal clutch axis and a resetting device for the mutual release of adjacent disks along a release distance, with the release distance being bounded by an abutment device. The abutment device includes at least one contact section of a clutch part movable along the longitudinal clutch axis and at least one contact section of an axially fixed clutch part, with the moving clutch part and the axially fixed clutch part having different thermal coefficients of expansion and with the contact sections at both sides cooperating such that the bounding of the release distance varies in dependence on the temperature, with at least one of the contact sections having a sloping surface.

Abstract: An adjustable position sensor is provided suitable for use with a clutch actuation control system. The position sensor includes: a rotatable shaft adapted to engage a control gear of the clutch actuation control system; and an encoder having a position indicator adjustably coupled to the shaft and operable to detect the position of the shaft over a range of motion that is less than the range of movement exhibited by the control gear. The position indicator of the encoder is adjustable in relation to the shaft so that the range of motion detected by the encoder can be correlated to an area of interest within the range of motion exhibited by the control gear.

Abstract: A power transmission device includes a rotary input member adapted to receive drive torque from a source of torque, a rotary output member adapted to provide drive torque to an output device and a torque transfer mechanism operable to transferring drive torque from the input member to the output member. The torque transfer mechanism includes a friction clutch assembly operably disposed between the input member and the output member and a hydraulic clutch actuation system operable for applying a clutch engagement force to the friction clutch assembly. The hydraulic clutch actuation system includes an electric motor drivingly coupled to a first piston. The first piston is slidably positioned within the housing for supplying pressurized fluid to an accumulator. The pressurized fluid within the accumulator is in communication with a second piston to provide the clutch engagement force.

Abstract: A torque transfer mechanism includes a multi-plate clutch assembly that is operably disposed between a first rotary and a second rotary member. A control system determines a desired quantity of torque to deliver to the second rotary member and controls the clutch to produce the desired torque.

Abstract: A lube pump is provided for supplying lubricant to various components of a power transmission unit of the type used in motor vehicles. The lube pump includes a pump assembly and a coupling mechanism for releaseably coupling the pump assembly to a driven shaft. The coupling is operable to release the pump assembly when the rotary speed of the shaft exceeds a threshold value.