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 vehicle includes an engine that generates drive torque and a power transfer device that selectively transfers the drive torque to a driveline. The power transfer device includes an input shaft, an output shaft and a torque biasing system. The torque biasing system has a clutch pack and an actuator that regulates engagement of the clutch pack. An on-demand lubrication system supplies a lubricating fluid flow through the clutch pack based on a control signal generated by a control system. A passively actuated positive displacement pump supplies the lubricating fluid flow through the clutch pack based on a speed differential between the input shaft and the output shaft.

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 vehicle includes an engine that generates drive torque and a power transfer device that selectively transfers the drive torque to a driveline. The power transfer device includes an input shaft, an output shaft and a torque biasing system. The torque biasing system has a clutch pack and an actuator that regulates engagement of the clutch pack. An on-demand lubrication system supplies a lubricating fluid flow through the clutch pack based on a control signal generated by a control system. A passively actuated positive displacement pump supplies the lubricating fluid flow through the clutch pack based on a speed differential between the input shaft and the output shaft.

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 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 an electric motor drivingly coupled to a pump. The pump supplies pressurized fluid to an accumulator. The pressurized fluid within the accumulator is selectively supplied to a piston to provide a clutch engagement force.

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 drive axle assembly for use in an all-wheel drive vehicle having a first hydraulic coupling operable to automatically transfer drive torque to a secondary driveline in response to slip of the primary driveline and a second hydraulic coupling operable to bias torque and limit slip between the wheels of the secondary driveline. The first hydraulic coupling is electronically-controlled.

Abstract: A power transfer system is provided and equipped with a torque transfer coupling which includes a clutch and a ball-screw actuator. The ball-screw actuator functions to axially translate an apply plate via a closed hydraulic system to operatively engage the clutch and vary the frictional engagement thereof.

Abstract: The present invention is directed to a power transfer system for a four-wheel drive vehicle equipped with a torque transfer coupling which includes a clutch pack and a ball-screw actuator. The ball-screw actuator functions to axially translates an apply plate to operatively engage the clutch pack and vary the frictional engagement. This arrangement yields numerous operational advantages over the prior art including, but not limited to, establishing a direct drive between the motor output shaft and the apply plate, concentric mounting of the actuator elements with the motor output shaft, and a simplified mechanical arrangement that reduces the number of frictional elements increasing operational efficiency and decreasing motor requirements.

Abstract: The present invention is directed to a power transfer system for a four-wheel drive vehicle equipped with a torque transfer coupling which includes a clutch pack and a ball-screw actuator. The ball-screw actuator functions to axially translates an apply plate to operatively engage the clutch pack and vary the frictional engagement. This arrangement yields numerous operational advantages over the prior art including, but not limited to, establishing a direct drive between the motor output shaft and the apply plate, concentric mounting of the actuator elements with the motor output shaft, and a simplified mechanical arrangement that reduces the number of frictional elements increasing operational efficiency and decreasing motor.

Abstract: A drive axle assembly for use in an all-wheel drive vehicle having a first hydraulic coupling operable to automatically transfer drive torque to a secondary driveline in response to slip of the primary driveline and a second hydraulic coupling operable to bias torque and limit slip between the wheels of the secondary driveline. The first hydraulic coupling is electronically-controlled.

Abstract: The present invention is directed to a power transfer system for a four-wheel drive vehicle equipped with a torque transfer coupling which includes a clutch pack and a ball-screw actuator. The ball-screw actuator functions to axially translates an apply plate to operatively engage the clutch pack and vary the frictional engagement. This arrangement yields numerous operational advantages over the prior art including, but not limited to, establishing a direct drive between the motor output shaft and the apply plate, concentric mounting of the actuator elements with the motor output shaft, and a simplified mechanical arrangement that reduces the number of frictional elements increasing operational efficiency and decreasing motor.

Abstract: A power transfer system is provided and equipped with a torque transfer coupling which includes a clutch and a ball-screw actuator. The ball-screw actuator functions to axially translate an apply plate via a closed hydraulic system to operatively engage the clutch and vary the frictional engagement thereof.

Abstract: A two-speed full-time transfer case includes an input shaft, first and second output shafts, a planetary gearset, an interaxle differential, and first and second clutch mechanisms. The planetary gearset includes a sun gear integral with the input shaft, an annulus gear, and pinion gears rotatably mounted on a carrier and which are meshed with the sun and annulus gears. The interaxle differential has an input driven by the carrier, a first output driving the first output shaft and a second output driving a transfer mechanism coupled to the second output shaft. The first clutch mechanism is a fluid-actuated bi-directional overrunning clutch operable for selectively braking the annulus gear. The second clutch mechanism is a fluid-released bi-directional overrunning clutch for selectively releasing the input shaft from coupled engagement with the carrier.

Abstract: A power transfer system is provided and equipped with a torque transfer coupling which includes a clutch and a ball-screw actuator. The ball-screw actuator functions to axially translate an apply plate via a closed hydraulic system to operatively engage the clutch and vary the frictional engagement thereof.

Abstract: A full-time power transfer system is disclosed to include a transfer case having a clutch assembly arranged to control speed differentiation and torque biasing across an interaxle differential, sensors for detecting and generating sensor signals indicative of various dynamic and operational characteristics of the vehicle, and a controller for controlling actuation of the clutch assembly in response to the sensor signals. Upon the occurrence of traction loss, the clutch assembly is automatically actuated for limiting interaxle slip while transferring increased drive torque to the non-slipping driveline. Under a preferred adaptive control scheme, the actuated condition of the clutch assembly is controllably modulated between its non-actuated and fully-actuated limits for automatically varying the magnitude of speed differentiation and torque biasing across the interaxle differential in response to changes in the dynamic and operational characteristics of the vehicle.

Abstract: A full-time power transfer system is disclosed to include a transfer case having a clutch assembly arranged to control speed differentiation and torque biasing across an interaxle differential, sensors for detecting and generating sensor signals indicative of various dynamic and operational characteristics of the vehicle, and a controller for controlling actuation of the clutch assembly in response to the sensor signals. Upon the occurrence of traction loss, the clutch assembly is automatically actuated for limiting interaxle slip while transferring increased drive torque to the non-slipping driveline. Under a preferred adaptive control scheme, the actuated condition of the clutch assembly is controllably modulated between its non-actuated and fully-actuated limits for automatically varying the magnitude of speed differentiation and torque biasing across the interaxle differential in response to changes in the dynamic and operational characteristics of the vehicle.

Abstract: A power transfer system is provided and equipped with a torque transfer coupling which includes a clutch and a ball-screw actuator. The ball-screw actuator functions to axially translate an apply plate via a closed hydraulic system to operatively engage the clutch and vary the frictional engagement thereof.

Abstract: A hydraulic coupling for use in an all wheel drive system, utilized in association with a front wheel drive transaxle, including a multi-plate clutch assembly operably connecting two relatively rotatable members and an actuator assembly for actuating the clutch assembly in response to speed differentiation between the two rotary members. The actuator assembly includes a hydraulic pump, a piston disposed in a piston chamber, and a fluid distribution system including a first flow path for supplying hydraulic fluid from a sump to the hydraulic pump and a second flow path for supplying hydraulic fluid from the hydraulic pump to the piston chamber. Hydraulic pressure in the piston chamber controls the magnitude of the clutch engagement force exerted by the piston on the clutch assembly. A control valve assembly is located in the piston chamber, in close proximity to the clutch pack where a majority of heat is generated.