Abstract: A power transfer unit is provided with a torque limiting coupling that limits the amount of torque that can be transferred to the driveline components when torque peaks occur while torque is transferred to the non-slipping wheels. The torque limiting coupling includes an engagement member disposed between an input from a driving member and an output to a driven member. The engagement member is located radially between and provides a frictional engagement between the input and the output. The engagement member is capable of slipping under heavy torque loads in order to protect the driveline components.

Abstract: A power take-off unit for a transaxle is provided with a unique double enveloping worm/worm gear transmission which has a ratio of the number of gear teeth on the worm gear to the number of threads on the worm which is low. The worm/worm gear transmission is more compact than conventional bevel gear systems which have typically been used in power take-off unit applications. The worm and worm gear transmission of the present invention also is quieter in operation and has a higher torque capacity than standard bevel gears of comparable size.

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 drive axle assembly includes a pair of axleshafts connected to a pair of wheels and a drive mechanism for selectively coupling a driven input shaft to one or both of the axleshafts. The drive mechanism includes first and second drive units that can be selectively engaged to control the magnitude of the drive torque transferred and the relative rotary speed between the input shaft and the axleshafts. Each drive unit includes a planetary gearset disposed between the input shaft and its corresponding axleshaft, a bi-directional overrunning clutch and a mode clutch that may be activated to cause the planetary gearset to establish different speed ratio drive connections between the input shaft and the axleshaft. A control system including an electronic control unit (ECU) and sensors are provided to control actuation of the mode clutches so as to control the side-to-side traction characteristics of the drive axle assembly.

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 torque coupling for use in a power transfer device. The torque coupling includes a friction clutch and a clutch actuator. The clutch actuator controls engagement of the friction clutch and has a first actuator plate rotatable about an axis, a second actuator plate adjacent to the first actuator plate, and a ballramp unit disposed between the first and second actuator plates. A piston assembly acts to induce rotation of the first actuator plate relative to the second actuator plate. Relative rotation between the first actuator plate and the second actuator plate induces linear movement of one of the first and second actuator plates along the axis to regulate engagement of the friction clutch.

Abstract: A method of actuating a clutch in a power transmission device having a first rotary member and a second rotary member includes compressing a spring, releasing the spring to pressurize a fluid, supplying the pressurized fluid to a piston, and applying a force from the piston to the clutch to transfer torque between the first and second rotary members.

Abstract: A torque transfer mechanism and a control system are disclosed for adaptively controlling the transfer of drive torque between first and second rotary members in a power transmission device of the type used in motor vehicle driveline applications. The torque transfer mechanism includes a main clutch assembly operably disposed between the first and second rotary members, a pilot clutch assembly and a clutch operator assembly. The clutch operator assembly includes a rotary cam driven by an electric motor and a pivotal mode fork.

Abstract: A drive axle assembly includes first and second axleshafts connected to a pair of wheels and a drive mechanism operable to selectively couple a driven input shaft to one or both of the axleshafts. The drive mechanism includes a differential, a speed changing unit operably disposed between the differential assembly and the first and second axleshafts, first and second mode clutches and a brake unit. The first mode clutch is operable 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 mode clutch is operable to increase the rotary speed of the second axleshaft so as to cause a decrease in the rotary speed of the first axleshaft. The brake unit is operable to engage the speed changing unit. A control system controls actuation of both mode clutches.

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: 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 drive axle assembly includes a pair of axleshafts connected to a pair of wheels, and a drive mechanism for selectively coupling a driven input shaft to one or both of the axleshafts. The drive mechanism includes first and second drive units that can be selectively engaged to control the magnitude of the drive torque transferred and the relative rotary speed between the input shaft and the axleshafts. Each drive unit includes a planetary gearset disposed between the input shaft and its corresponding axleshaft, and a pair of mode clutches that may be activated to cause the planetary gearset to establish different speed ratio drive connections between the input shaft and the axleshaft. A control system including an electronic control unit (ECU) and sensors are provided to control actuation of the clutches so as to control the side-to-side traction characteristics of the drive axle assembly.

Abstract: A hybrid drive system for a four-wheel drive system arranged to supply motive power to a first output shaft of a transfer case from an internal combustion engine and to a second output shaft from an electric motor/generator. The transfer case includes a reduction gearset driven by the electric motor/generator, a power take-off unit driven by the reduction gearset, and a disconnect clutch operable for selectively coupling the reduction gearset to the second output shaft. This hybrid drive arrangement permits installation of a modified transfer case in place of a conventional transfer case for use in a traditional four-wheel drive driveline arrangement.

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 releasable 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: A drive axle assembly includes first and second axleshafts connected to a pair of wheels and a drive mechanism operable to selectively couple a driven input shaft to one or both of the axleshafts. The drive mechanism includes a differential, a speed changing unit operably disposed between the differential assembly and one of the first and second axleshafts, and first and second mode clutches. The first mode clutch is operable to decrease the rotary speed of the second axleshaft which, in turn, causes a corresponding increase in the rotary speed of the first axleshaft. The second mode clutch is operable to increase the rotary speed of the second axleshaft so as to cause a decrease in the rotary speed of the first axleshaft. A control system controls actuation of both mode clutches.

Abstract: A drive axle assembly includes first and second axleshafts connected to a pair of wheels and a drive mechanism operable to selectively couple a driven input shaft to one or both of the axleshafts. The drive mechanism includes a differential, a speed changing unit operably disposed between the differential assembly and one of the first and second axleshafts, and first and second mode clutches. The first mode clutch is operable to engage the speed changing unit for reducing the rotary speed of the second axleshaft relative to the rotary speed of the first axleshaft. The second mode clutch is operable to engage the speed changing unit for increasing the rotary speed of the second axleshaft relative to the rotary speed of the first axleshaft. A control system controls actuation of both mode clutches.

Abstract: A torque transfer mechanism for controlling the magnitude of a clutch engagement force exerted on a clutch pack that is operably disposed between a first rotary member and a second rotary member includes a hydraulic clutch actuation system. The hydraulic clutch actuation system includes a primary fluid circuit coupled to a secondary fluid circuit by a pressure intensifier. The pressure intensifier provides magnified pressure to a piston for actuating the clutch pack.

Abstract: A dual-clutch transmission for use in a motor vehicle having an engine and a driveline includes an output shaft adapted for connection to the driveline and a planetary gearset in constant driving engagement with the output shaft. An input shaft is driven by the engine. A first constant mesh gearset is in selective driving communication with a first member of the planetary gearset. A second constant mesh gearset is in selective driving communication with a second member of the planetary gearset. A first clutch is operable for establishing a releasable drive connection between the input shaft and the first constant mesh gearset. A second clutch is operable for establishing a releasable drive connection between the input shaft and the second constant mesh gearset. A motor is selectively drivingly coupled to a third member of the planetary gearset.

Abstract: A torque transfer mechanism having a multi-plate friction clutch connecting a pair of rotary members and an electrohydraulic clutch system for controlling engagement of the friction clutch. The electrohydraulic clutch system can include an actuator with first and second components with a plurality of actuation chambers that are employed to control the position of the second component relative to the first component. Relatively high pressure fluid may be directed through or around one or more bypassed portions of the actuation chambers when relatively low compressive clutch engagement forces are to be exerted on the friction clutch. The bypassed portions of the actuation chambers may be sequentially or progressively operated based on a position of the second component relative to the first component to increase an amount of force that is applied by actuator.

Abstract: A drive axle assembly includes first and second axleshafts connected to a pair of wheels and a drive mechanism operable to selectively couple a driven input shaft to one or both of the axleshafts. The drive mechanism includes a differential, first and speed changing units and first and second mode clutches. The first mode clutch is operable in association with the first speed changing unit 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 mode clutch is operable in association with the second speed changing unit to increase the rotary speed of the second axleshaft so as to cause a decrease in the rotary speed of the first axleshaft. A control system controls actuation of both mode clutches.