A hydraulic system for an automatic transmission of a motor vehicle, including a high pressure circuit in which a pressure accumulator, at least one clutch and a gear selector are connected, and comprising a low pressure circuit for cooling the clutch, wherein the high pressure circuit and the low pressure circuit have at least one hydraulic pump that can be driven by an electric motor, and including a control unit that actuates the electric motor of the hydraulic pump when a pressure accumulator charging requirement is detected, wherein the high and low pressure circuits are connected via a bypass line to an integrated accumulator charging valve.

A switching unit for a hybrid module for a drivetrain of a hybrid vehicle is provided. A first clutch is selectively closable to transmit torque from a drive shaft to a first output shaft. A second clutch is selectively closable to transmit torque from the drive shaft to a second output shaft. A plurality of ducts include a cooling oil supply duct, a first cooling oil duct configured to supply cooling oil to the first clutch, and a second cooling oil duct configured to supply cooling oil to the second duct. A switching unit selectively supplies cooling oil to the first and second clutches via the first and second cooling oil ducts, respectively, wherein the switching unit includes a slide having an aperture extending therethrough, and the slide is configured to move to alternatively fluidly the coiling oil supply duct with the first or second cooling oil ducts.

A cooling oil guiding device for rotating component parts. An annular oil channel extends in radial direction and cooling oil can be supplied from radially inward. The oil channel is partially open radially outwardly. A sealing area is provided in a radially outer area of the oil channel having blocking elements and outlet elements., The blocking elements are arranged radially inwardly of the outlet elements and have at least two passages in radial direction which are distributed along the circumference. Outlet channels aligned with the passages and inlets which are disposed between the outlet channels in circumferential direction are formed by the outlet elements. An annular channel is provided between the blocking elements and the outlet elements to connect the inlets with the outlet channels and passages, respectively.

A clutch subassembly for a motorcycle includes a hub, a plurality of driven discs and an elastic element. The hub includes a plurality of projecting protrusions, wherein the plurality of projecting protrusions define wide through openings capable of promoting a lubrication and, at a same time, the plurality of projecting protrusions reduce a weight of the clutch subassembly.

A gear spindle device for a rolling mill includes: a spindle outer cylinder having, at a first end side, an inner circumferential surface provided with an inner circumferential gear; a spindle inner cylinder having an outer circumferential surface provided with an outer circumferential gear which engages with the inner circumferential gear; a seal member disposed between the spindle outer cylinder and the spindle inner cylinder, for holding a lubricant oil at an engagement portion between the inner circumferential gear and the outer circumferential gear; and a coolant supply unit disposed at an opposite side to the seal member across the engagement portion in an axial direction of the spindle outer cylinder, for supplying a coolant toward the spindle outer cylinder in a formation region of the engagement portion where the engagement portion is formed.

A friction part for a frictionally operating device includes a friction lining carrier and a friction lining. The friction lining includes friction lining pieces arranged in two rows to form an annular friction surface. The friction surface has an inner edge, an outer edge, and a groove set. The groove set has a first stem groove between the inner edge and a first branching point, a first branch groove between the first branching point and a first connecting point, a second branch groove between the first branching point and a second connecting point, a third branch groove between a second branching point and the second connecting point, and a second stem groove between the second connecting point and the outer edge. The first stem groove, and first and second branch grooves form a y shape. The second stem groove, and second and third branch grooves form an inverted y shape.

A friction part for a frictionally operating device includes a friction lining carrier and a friction lining. The friction lining includes pentagonal friction lining pieces arranged on the friction lining carrier to form an annular friction surface. Each of the pentagonal friction lining pieces has a two-dimensional shape made up of a rectangle and an isosceles triangle, and a base coinciding with a relatively long side of the rectangle. A radially inner row includes pentagonal friction lining pieces with a same first shape, a same first size, and a same first tip directed radially outward, and a radially outer row includes pentagonal friction lining pieces with a same second shape, a same second size, and a same second tip directed radially inward. The annular friction surface has an inner edge, an outer edge, and a groove set formed between the pentagonal friction lining pieces.

A flexible unit absorbing misalignment and transmitting torque from a driving shaft to a driven shaft is provided between a pair of flanges individually provided on each of the driving shaft side and the driven shaft side, both the driving shaft and the driven shaft being hollow. A communication passage letting hollow regions of the driving shaft and the driven shaft communicate with each other to form a circulation space for a cooling fluid is provided in the flexible unit. The flow of the cooling fluid cooling a driving source driving and rotating the driving shaft from the inside is created in the circulation space. A seal portion seals between the circulation space and an outside space to prevent leakage of the cooling fluid from the circulation space to the outside space.

A clutch assembly includes a shaft, a backing plate fixed to the shaft, a plurality of clutch plates, a hydraulic piston, and a balance dam. The hydraulic piston is sealed to the shaft and axially slidable on the shaft to clamp the plurality of clutch plates against the backing plate to close the clutch assembly. The balance dam is fixed to the shaft and disposed axially between the backing plate and the hydraulic piston. The balance dam has a cooling flow orifice and a cooling flow valve for adjusting cooling oil flow through the cooling flow orifice. In some example embodiments, the cooling flow valve is a reed valve with a displaceable steel plate fixed to the balance dam and preloaded against the balance dam to cover the cooling flow orifice.

A multi-plate dual clutch for coupling a motor vehicle engine to a drive shaft of a motor vehicle transmission and to an auxiliary power take-off output shaft of the motor vehicle. The dual clutch includes a drive clutch for coupling the motor vehicle engine with the drive shaft, and an auxiliary power take-off clutch for coupling the motor vehicle engine with the auxiliary output shaft. The drive clutch and the auxiliary power take-off clutch can each to be operated independently of one another by a separate lever mechanism. The dual clutch includes a wet chamber housing in which the drive clutch, the auxiliary power take-off clutch, and the respective lever mechanisms are accommodated in fluid-tight relationship.