Abstract: A differential can comprise a pilot clutch, a main clutch, a first ball ramp configured to act on the pilot clutch, and a second ball ramp configured to actuate the main clutch when the pilot clutch acts on the second ball ramp. An electromagnetic differential can comprise a carrier, a stator mounted on the carrier, a pilot clutch in the carrier, and a main clutch in the carrier. An electromagnetic differential can comprise a carrier and a first side gear and a second side gear in the carrier. A pilot clutch can be in the carrier surrounding a portion of the first side gear. A main clutch can be in the carrier surrounding a portion of the pilot clutch and surrounding a portion of the first side gear.

Abstract: A electric locker differential assembly includes a first and second side gear. A pinion gear set is disposed between the first side gear and the second side gears. An engagement shaft includes flyweights disposed on the engagement shaft which are moveable between retracted and extended positions to lock and unlock the differential assembly. A lockout shaft includes a pawl disposed thereon. An electrical adjustment mechanism includes an actuator operably connected with an adjustment nut or rod. An electrical adjustment biasing spring includes a first leg retained by the adjustment nut and a second leg connected with the pawl wherein movement of the adjustment nut by the actuator varies a biasing force applied to the pawl.

Abstract: A method of determining clutch torque for a limited slip differential gear mechanism on a vehicle includes obtaining an estimated driveline torque. A desired bias torque is established. A necessary clutch torque required to achieve the desired bias torque is determined. The necessary clutch torque is commanded based on the estimated driveline torque to achieve the desired bias torque.

Abstract: A electric locker differential assembly includes a first and second side gear. A pinion gear set is disposed between the first side gear and the second side gears. An engagement shaft includes flyweights disposed on the engagement shaft which are moveable between retracted and extended positions to lock and unlock the differential assembly. A lockout shaft includes a pawl disposed thereon. An electrical adjustment mechanism includes an actuator operably connected with an adjustment nut or rod. An electrical adjustment biasing spring includes a first leg retained by the adjustment nut and a second leg connected with the pawl wherein movement of the adjustment nut by the actuator varies a biasing force applied to the pawl.

Abstract: A hydraulic control unit that delivers hydraulic fluid to a limited slip differential includes a hydraulic control unit housing having a manifold housing portion and an accumulator housing portion. The accumulator housing portion and manifold housing portion cooperate to form an accumulator chamber that houses the biasing assembly and the piston. A motor is disposed on a first side of the manifold housing portion, and a pump is disposed on a second side of the manifold portion, opposite the first side. The pump is configured to pump fluid into the accumulator chamber of the accumulator housing portion. A reservoir is defined by at least one of the manifold housing portion and the accumulator housing portion, and a bag filter disposed in the reservoir is configured to filter fluid flowing through the reservoir.

Abstract: A differential can comprise a pilot clutch, a main clutch, a first ball ramp configured to act on the pilot clutch, and a second ball ramp configured to actuate the main clutch when the pilot clutch acts on the second ball ramp. An electromagnetic differential can comprise a carrier, a stator mounted on the carrier, a pilot clutch in the carrier, and a main clutch in the carrier. An electromagnetic differential can comprise a carrier and a first side gear and a second side gear in the carrier. A pilot clutch can be in the carrier surrounding a portion of the first side gear. A main clutch can be in the carrier surrounding a portion of the pilot clutch and surrounding a portion of the first side gear.

Abstract: A hydraulic control unit that delivers hydraulic fluid to a limited slip differential includes a hydraulic control unit housing, a motor and a pump. The hydraulic control unit housing has a manifold housing portion and an accumulator housing portion. The manifold housing portion defines a fluid pathway arrangement for communicating fluid along at least a first fluid pathway. The accumulator housing portion houses an accumulator assembly having a biasing assembly and a piston. The accumulator housing portion and manifold housing portion cooperate to form an accumulator chamber that houses the biasing assembly. The motor is disposed on the first side of the manifold housing portion. The pump is disposed on a second side of the manifold portion, opposite the first side. The pump is configured to pump fluid into the accumulator chamber of the accumulator housing portion.

Abstract: A hydraulic control unit (HCU) assembly, for an electro-hydraulic limited slip differential system for a vehicle, includes a support bracket configured to couple to an underbody of the vehicle in a location remote from a live axle assembly of the vehicle, and an HCU including an integrated accumulator and reservoir assembly, a control valve assembly, and a motor and hydraulic pump assembly. The HCU is coupled to the support bracket.

Abstract: An electronic limited slip coupling constructed in accordance to one example of the present disclosure includes a sleeve, a support shaft, a hydraulic control unit, a clutch assembly and a case. The sleeve has a first set of splines projecting inwardly and meshed for engagement with an axle. The support shaft has a second set of splines configured to mesh with a first housing of a differential assembly. The hydraulic control unit has an accumulator housing and a motor. The motor is configured to pump fluid into an accumulator chamber of the accumulator housing. The clutch assembly receives fluid from the hydraulic control unit. The clutch assembly has a clutch pack positioned between a clutch piston and a portion of a clutch basket. The clutch assembly is operable to selectively interlock the sleeve and the support shaft. The case supports the electronic limited slip coupling as an assembled unit.

Abstract: An electro-hydraulic limited slip differential system for a vehicle includes an axle assembly having an axle housing having an aperture formed therein, and an electro-hydraulic limited slip differential assembly disposed within the axle housing. The limited slip differential assembly includes a differential case, a differential gear assembly disposed in the differential case, a clutch assembly having a clutch pack and a clutch actuator assembly, and a hydraulic fitting disposed at least partially within the aperture. The hydraulic fitting is coupled to a hydraulic port of the clutch actuator assembly.

Abstract: A hydraulic control unit that delivers hydraulic fluid to a limited slip differential includes a hydraulic control unit housing, a motor and a pump. The hydraulic control unit housing has a manifold housing portion and an accumulator housing portion. The manifold housing portion defines a fluid pathway arrangement for communicating fluid along at least a first fluid pathway. The accumulator housing portion houses an accumulator assembly having a biasing assembly and a piston. The accumulator housing portion and manifold housing portion cooperate to form an accumulator chamber that houses the biasing assembly. The motor is disposed on the first side of the manifold housing portion. The pump is disposed on a second side of the manifold portion, opposite the first side. The pump is configured to pump fluid into the accumulator chamber of the accumulator housing portion.

Abstract: A method of determining clutch torque for a limited slip differential gear mechanism on a vehicle includes obtaining an estimated driveline torque. A desired bias torque is established. A necessary clutch torque required to achieve the desired bias torque is determined. The necessary clutch torque is commanded based on the estimated driveline torque to achieve the desired bias torque.

Abstract: A hydraulic control unit that delivers hydraulic fluid to a limited slip differential includes a hydraulic control unit housing, a sump and a motor. The hydraulic control unit housing has an accumulator housing portion that houses a biasing assembly and a piston. The sump is defined in the hydraulic control unit housing and at least partially occupies a common space with the accumulator housing portion. The motor is configured to pump fluid into an accumulator chamber of the accumulator housing portion. The fluid pumped into the accumulator housing portion at least partially collapses the biasing assembly and introduces a pre-charge into the hydraulic control unit. The biasing assembly is configured to expand and urge the piston in a first direction resulting in fluid being communicated from the hydraulic control unit and into the limited slip differential.

Abstract: A hydraulic control unit that delivers hydraulic fluid to a limited slip differential includes a hydraulic control unit housing, a sump and a motor. The hydraulic control unit housing has an accumulator housing portion that houses a biasing assembly and a piston. The sump is defined in the hydraulic control unit housing and at least partially occupies a common space with the accumulator housing portion. The motor is configured to pump fluid into an accumulator chamber of the accumulator housing portion. The fluid pumped into the accumulator housing portion at least partially collapses the biasing assembly and introduces a pre-charge into the hydraulic control unit. The biasing assembly is configured to expand and urge the piston in a first direction resulting in fluid being communicated from the hydraulic control unit and into the limited slip differential.

Abstract: An electronic limited slip coupling constructed in accordance to one example of the present disclosure includes a sleeve, a support shaft, a hydraulic control unit, a clutch assembly and a case. The sleeve has a first set of splines projecting inwardly and meshed for engagement with an axle. The support shaft has a second set of splines configured to mesh with a first housing of a differential assembly. The hydraulic control unit has an accumulator housing and a motor. The motor is configured to pump fluid into an accumulator chamber of the accumulator housing. The clutch assembly receives fluid from the hydraulic control unit. The clutch assembly has a clutch pack positioned between a clutch piston and a portion of a clutch basket. The clutch assembly is operable to selectively interlock the sleeve and the support shaft. The case supports the electronic limited slip coupling as an assembled unit.

Abstract: A hydraulic control unit (HCU) assembly, for an electro-hydraulic limited slip differential system for a vehicle, includes a support bracket configured to couple to an underbody of the vehicle in a location remote from a live axle assembly of the vehicle, and an HCU including an integrated accumulator and reservoir assembly, a control valve assembly, and a motor and hydraulic pump assembly. The HCU is coupled to the support bracket.

Abstract: An electro-hydraulic limited slip differential system for a vehicle includes an axle assembly having an axle housing having an aperture formed therein, and an electro-hydraulic limited slip differential assembly disposed within the axle housing. The limited slip differential assembly includes a differential case, a differential gear assembly disposed in the differential case, a clutch assembly having a clutch pack and a clutch actuator assembly, and a hydraulic fitting disposed at least partially within the aperture. The hydraulic fitting is coupled to a hydraulic port of the clutch actuator assembly.

Abstract: A limited-slip driveline apparatus including a first driveline component that is rotatable relative to a second driveline component. The driveline apparatus also includes a clutch. The driveline apparatus further includes an actuation arrangement for actuating the clutch. The actuation arrangement includes a hydraulic pump that pumps hydraulic fluid through a hydraulic circuit when relative rotation exists between the first and second driveline components. The hydraulic pressure generated by the hydraulic pump within the hydraulic circuit is used to actuate the clutch. The actuation arrangement also includes a flow regulating valve for regulating a hydraulic fluid flow rate through the hydraulic circuit. The flow regulating valve is configured to prevent the hydraulic fluid flow rate from exceeding a set maximum flow rate regardless of a magnitude of the hydraulic pressure in the hydraulic circuit.

Abstract: The present disclosure relates to a limited-slip clutch system and method. In one aspect, the limited-slip clutch actuation system can include a hydraulic pump operated by a variable speed drive wherein the pump can be configured to generate hydraulic flow in a hydraulic circuit including an actuation branch line that actuates a clutch. The circuit may also include a flow regulating valve for regulating a hydraulic fluid flow rate through the hydraulic circuit wherein the flow regulating valve can be configured to prevent the hydraulic fluid flow rate from exceeding a set maximum flow rate regardless of a magnitude of the hydraulic pressure in the hydraulic circuit. In operation, the pump speed can be controlled based on a command pressure set point and the measured pressure in the actuation branch line and to minimize operational costs by operating the pump at a transition region of the system pressure-pump speed curve.