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 hydraulic coupling having a multi-plate friction clutch assembly operably connecting a pair of rotary members and a hydramechanical clutch actuator for automatically controlling engagement of the friction clutch assembly. The clutch actuator includes a hydraulic fluid pump, a hydraulically-actuated rotary operator, and a ball ramp mechanism. The hydraulic fluid pump is operable to draw low pressure fluid from a sump and deliver high pressure fluid to a series of actuation chambers defined between coaxially aligned first and second components of the rotary operator. The magnitude of the fluid pressure delivered to the actuation chamber controls the angular movement of the second component relative to the first component. Translational movement of the second cam member results in a compressive clutch engagement force being exerted on the friction clutch assembly, thereby controlling the drive torque transferred from the first rotary member to the second rotary member.

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 decrease the rotary speed of the first axleshaft which, in turn, causes a corresponding increase in the rotary speed of the second axleshaft. The second mode clutch is operable in association with the second speed changing unit to decrease the rotary speed of the second axleshaft so as to cause an increase 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, 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.

Abstract: A torque transfer mechanism having a transfer clutch connecting a pair of rotary members and a electrohydraulic clutch actuator for controlling engagement of the transfer clutch. The clutch actuator includes a hydraulic pump and a hydraulically-actuated rotary operator. The hydraulic pump draws low pressure fluid from a sump and delivers high pressure fluid to a series of actuation chambers defined between coaxially aligned first and second components of the rotary operator. The magnitude of the fluid pressure delivered to the actuation chamber controls angular movement of the second component relative to the first component for energizing a pilot ball ramp unit. The pilot ball ramp mechanism applies a clutch actuation force on a pilot friction clutch which energized a main ball ramp unit for applying a clutch engagement force to a main friction clutch. A hydraulic control system adaptively regulates the fluid pressure delivered to the actuation chamber.

Abstract: A torque transfer mechanism having a multi-plate friction clutch connecting a pair of rotary members and a electrohydraulic clutch actuator for controlling engagement of the friction clutch. The clutch actuator includes a hydraulic pump, a hydraulically actuated rotary operator, and a thrust mechanism. The hydraulic pump draws low pressure fluid from a sump and selectively delivers high pressure fluid to a series of actuation chambers and return chambers defined between coaxially aligned first and second components of the rotary operator. The magnitude of the fluid pressure delivered to the actuation chamber controls angular movement of the second component relative to the first component for energizing the thrust mechanism. The thrust mechanism applies a clutch engagement force on the friction clutch, thereby transferring drive torque from the first rotary member to the second rotary member. An electrohydraulic control system regulates the fluid pressure delivered to the actuation and return chambers.

Abstract: A torque transfer mechanism having a transfer clutch connecting a pair of rotary members and a electrohydraulic clutch actuator for controlling engagement of the transfer clutch. The clutch actuator includes a hydraulic pump and a hydraulically-actuated rotary operator. The hydraulic pump draws low pressure fluid from a sump and delivers high pressure fluid to a series of actuation chambers defined between coaxially aligned first and second components of the rotary operator. The magnitude of the fluid pressure delivered to the actuation chamber controls angular movement of the second component relative to the first component for energizing a pilot ball ramp unit. The pilot ball ramp mechanism applies a clutch actuation force on a pilot friction clutch which energized a main ball ramp unit for applying a clutch engagement force to a main friction clutch. A hydraulic control system adaptively regulates the fluid pressure delivered to the actuation chamber.

Abstract: A torque transfer mechanism having a multi-plate friction clutch connecting a pair of rotary members and a electrohydraulic clutch actuator for controlling engagement of the friction clutch. The clutch actuator includes a hydraulic pump, a hydraulically-actuated rotary operator, and a thrust mechanism. The hydraulic pump draws low pressure fluid from a sump and selectively delivers high pressure fluid to a series of actuation chambers and return chambers defined between coaxially aligned first and second components of the rotary operator. The magnitude of the fluid pressure delivered to the actuation chamber controls angular movement of the second component relative to the first component for energizing the thrust mechanism. The thrust mechanism applies a clutch engagement force on the friction clutch, thereby transferring drive torque from the first rotary member to the second rotary member. An electrohydraulic control system regulates the fluid pressure delivered to the actuation and return chambers.

Abstract: A torque transfer mechanism having a transfer clutch connecting a pair of rotary members and a electrohydraulic clutch actuator for controlling engagement of the transfer clutch. The clutch actuator includes a hydraulic pump and a hydraulically-actuated rotary operator. The hydraulic pump draws low pressure fluid from a sump and delivers high pressure fluid to a series of actuation chambers defined between coaxially aligned first and second components of the rotary operator. The magnitude of the fluid pressure delivered to the actuation chamber controls angular movement of the second component relative to the first component for energizing a pilot ball ramp unit. The pilot ball ramp mechanism applies a clutch actuation force on a pilot friction clutch which energized a main ball ramp unit for applying a clutch engagement force to a main friction clutch. A hydraulic control system adaptively regulates the fluid pressure delivered to the actuation chamber.

Abstract: A torque transfer mechanism having a multi-plate friction clutch connecting a pair of rotary members and a electrohydraulic clutch actuator for controlling engagement of the friction clutch. The clutch actuator includes a hydraulic pump, a hydraulically-actuated rotary operator, and a thrust mechanism. The hydraulic pump draws low pressure fluid from a sump and selectively delivers high pressure fluid to a series of actuation chambers and return chambers defined between coaxially aligned first and second components of the rotary operator. The magnitude of the fluid pressure delivered to the actuation chamber controls angular movement of the second component relative to the first component for energizing the thrust mechanism. The thrust mechanism applies a clutch engagement force on the friction clutch, thereby transferring drive torque from the first rotary member to the second rotary member. An electrohydraulic control system regulates the fluid pressure delivered to the actuation and return chambers.

Abstract: A torque transfer mechanism having a multi-plate friction clutch connecting a pair of rotary members and a electrohydraulic clutch actuator for controlling engagement of the friction clutch. The clutch actuator includes a hydraulic pump, a hydraulically-actuated rotary operator, and a ball ramp mechanism. The hydraulic pump draws low pressure fluid from a sump and delivers high pressure fluid to a series of actuation chambers defined between coaxially aligned first and second components of the rotary operator. The magnitude of the fluid pressure delivered to the actuation chamber controls angular movement of the second component relative to the first component for energizing the ball ramp mechanism. The ball ramp mechanism applies a clutch engagement force on the friction clutch assembly, thereby transferring drive torque from the first rotary member to the second rotary member. A hydraulic control system adaptively regulates the fluid pressure delivered to the actuation chamber.

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 an actuator having an inner sleeve, an outer sleeve, and a plurality of balls. The inner sleeve is supported for rotation relative to the first rotary member and each of the inner and outer sleeves includes a spiral groove aligned with the other. The balls are positioned within the spiral grooves between the inner and outer sleeves. An electric motor selectively rotates one of the inner and outer sleeves so as to induce axial movement of the other of the inner and outer sleeves to engage the clutch.

Abstract: A hydraulic coupling having a multi-plate friction clutch assembly operably connecting a pair of rotary members and a hydramechanical clutch actuator for automatically controlling engagement of the friction clutch assembly. The clutch actuator includes a hydraulic fluid pump, a hydraulically-actuated rotary operator, and a ball ramp mechanism. The hydraulic fluid pump is operable to draw low pressure fluid from a sump and deliver high pressure fluid to a series of actuation chambers defined between coaxially aligned first and second components of the rotary operator. The magnitude of the fluid pressure delivered to the actuation chamber controls the angular movement of the second component relative to the first component. Translational movement of the second cam member results in a compressive clutch engagement force being exerted on the friction clutch assembly, thereby controlling the drive torque transferred from the first rotary member to the second rotary member.

Abstract: A power transfer system is provided and equipped with a torque transfer coupling which includes a stage 2 clutch and a clutch actuator. The clutch actuator includes stage 1 and stage 2 ball ramp actuators as well as a stage 1 clutch operably positioned between the ball ramp actuators to operatively engage the stage 2 clutch and vary the frictional engagement thereof.

Abstract: A power transfer system is provided and equipped with a torque transfer coupling which includes a stage 2 clutch and a clutch actuator. The clutch actuator includes stage 1 and stage 2 ball ramp actuators as well as a stage 1 clutch operably positioned between the ball ramp actuators to operatively engage the stage 2 clutch and vary the frictional engagement thereof.