Abstract: A compact planetary differential gear set includes first (130A) and second (130B) sun gears, a first set (200A) and a second set (200B) of planet gears (220), and a carrier (160) with a ring gear (190). Enmeshing gear pairs (210) are formed from one planet gear from each set. The first and second planet gear sets enmesh the first and second sun gears, respectively. The ring gear does not extend into an annular region containing the planet gears thereby allowing four or more gear pairs to compactly fit into the annular region. The carrier is a weldment and substantially encloses the sun gears and the planet gears permanently. The differential requires no fasteners or post-weld machining and may have a higher capacity, lower cost, smaller size, lower part number count, and/or lower amounts of material compared with conventional differentials. The differential is suited for motor vehicle applications.

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 compact planetary differential gear set includes first (130A) and second (130B) sun gears, a first set (200A) and a second set (200B) of planet gears (220), and a carrier (160) with a ring gear (190). Enmeshing gear pairs (210) are formed from one planet gear from each set. The first and second planet gear sets enmesh the first and second sun gears, respectively. The ring gear does not extend into an annular region containing the planet gears thereby allowing four or more gear pairs to compactly fit into the annular region. The carrier is a weldment and substantially encloses the sun gears and the planet gears permanently. The differential requires no fasteners or post-weld machining and may have a higher capacity, lower cost, smaller size, lower part number count, and/or lower amounts of material compared with conventional differentials. The differential is suited for motor vehicle applications.

Abstract: A hydraulic actuation system includes a differential unit having a hydraulically-actuated differential, a power steering unit, a hydraulic pump, a reservoir, a controller, an electronically-controlled flow control manifold, and a proportional pressure control solenoid valve. A flow control manifold may control fluid flow to the power steering unit and the differential. The manifold may include a manifold inlet connected to a pump; first manifold outlet connected to a differential; second manifold outlet connected to a reservoir; third manifold outlet connected to a power steering unit; two-way solenoid valve connected to a manifold inlet and controlled by a controller; flow control valve connected to a two-way solenoid valve and a first manifold outlet; and a pressure differential sensing valve connected to a two-way solenoid valve, the manifold inlet, and the third manifold outlet. A proportional pressure control solenoid valve may connect the first manifold outlet and the differential.

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.

Abstract: A hydraulic control unit that delivers hydraulic fluid to a limited slip differential constructed in accordance to the present disclosure can include a hydraulic control unit housing, a motor, a gerotor gear assembly and an interface plate. The hydraulic control unit housing can have a housing mounting surface. The motor can include an output shaft and a motor mounting plate that has a motor mounting surface. The gerotor gear assembly can include an inner and outer gerotor gear. The outer gerotor gear can be formed of a first material having a first coefficient of expansion. The interface plate can be mounted between the housing mounting surface and the motor mounting surface. The interface plate can receive the outer gerotor gear in an interference fit. The interface plate is formed of a second material having a second coefficient of expansion that is substantially equivalent to the first coefficient of expansion.

Abstract: A cover for a differential housing is disclosed herein. The cover can include a body, a flange, a fluid reservoir, a first fluid conduit, and second fluid conduit. The body can have an inwardly-facing surface and outwardly-facing surface opposite the inwardly-facing surface. The flange can extend about at least a portion of a perimeter of the body. The fluid reservoir can be defined within the body and have a reservoir outlet and a return port. The first fluid conduit can be defined within the body. The first fluid conduit can be spaced from the fluid reservoir and extend between a first inlet and a first outlet. The second fluid conduit can be defined within the body and extend between the first fluid conduit and the return port of the fluid reservoir.

Abstract: A hydraulic actuation system includes a differential unit having a hydraulically-actuated differential, a power steering unit, a hydraulic pump, a reservoir, a controller, an electronically-controlled flow control manifold, and a proportional pressure control solenoid valve. A flow control manifold may control fluid flow to the power steering unit and the differential. The manifold may include a manifold inlet connected to a pump; first manifold outlet connected to a differential; second manifold outlet connected to a reservoir; third manifold outlet connected to a power steering unit; two-way solenoid valve connected to a manifold inlet and controlled by a controller; flow control valve connected to a two-way solenoid valve and a first manifold outlet; and a pressure differential sensing valve connected to a two-way solenoid valve, the manifold inlet, and the third manifold outlet. A proportional pressure control solenoid valve may connect the first manifold outlet and the differential.

Abstract: A limited slip differential assembly includes a planetary gear assembly, a differential case, a differential gear assembly and a hydraulic clutch assembly. The differential case is coupled for rotation with a portion of the planetary gear assembly. The differential gear assembly is arranged within the differential case and includes a first side gear and a second side gear for coupling with first and second drive wheels of a vehicle, respectively. The hydraulic clutch assembly includes a clutch pack and a clutch actuator. Pressurized hydraulic fluid from a transmission pump is selectively provided to the clutch pack to actuate the clutch pack between an open configuration, in which the side gears rotate independently, and a fully closed configuration, in which the side gears rotate together such that the first and second drive wheels rotate at a same speed.

Abstract: The present disclosure relates to 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 configured to resist relative rotation between the first driveline component and the second driveline component at least when the clutch is actuated. 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.