Provided is a hydraulic power transmission device enabling to minimize a pressure loss in an oil passage downstream from a piston chamber of a hydraulic clutch, and to properly prevent reduction in transmission torque capacity in the hydraulic clutch. Left and right pressure regulating valves (8L, 8R) regulating pressure of oil flowing out from piston chambers (59L, 59R) of left and right clutch devices (5L, 5R) are arranged adjacent to a downstream of the piston chamber (59). This can shorten an oil passage from the piston chamber (59) to the pressure regulating valve (8) and minimize pressure loss in the oil passage. Due to better flexibility of arrangement of the pressing load receiving member (82) receiving a pressing force (thrust) of the piston member (57), thrust efficiency of the hydraulic piston (57) improves to properly prevent reduction in transmission torque capacity in the hydraulic clutch (5).

An improved torque converter damper disc and/or clutch that includes the use of a parametric spring system. The parametric spring is configured to address critical inflection and pinch points along the spring longitudinal length. These critical points are areas of higher applied stress due to torsional stress and bending stress, the latter of which mainly attributed to centrifugal loading.

A wedge clutch imparts a wedging effect to selectively transfer power through powertrain components. The wedge clutch includes a hub configured to rotate about an axis and having a tapered hub surface. A rotatable member is configured to rotate about the axis. A plurality of wedge segments are arranged annularly about the axis and are disposed radially between the hub and the rotatable member. The wedge segments can collectively radially expand and contract to lock and unlock the clutch. Each wedge segment defines an aperture therethrough. A cage assembly includes a plurality of pins that each extend through a respective one of the apertures to control relative radial movement of the wedge segments.

Protruding portions have an agitation face on the side surface thereof to agitate or dam hydraulic oil. An oil chamber defining portion has a supply hole that is allowed to supply the hydraulic oil from outside a hydraulic oil chamber by communicating with the hydraulic oil chamber from the rotational center side. When the protruding portions abut against the oil chamber defining portion so that the capacity of the hydraulic oil chamber is minimized, the supply hole faces, in a radial direction, a flow passage that is surrounded by circumferentially adjacent ones of the protruding portions, an oil chamber defining portion, and a piston.

A clutch plate includes a disk-shaped plate having an outer perimeter edge and a center opening having an inner perimeter edge, one of the outer perimeter edge and the inner perimeter edge including splines circumferentially there along, the disk-shaped plate having a first side face and a second side face each including a friction surface configured to engage a first opposing clutch plate, the disk-shaped plate having a plurality of return springs integrally formed in the disk-shaped plate, the plurality of return springs being bent to extend outward from a surface of one of the first side face and the second side face.

A clutch includes a hub and a carrier supported for rotation about a common axis. The carrier has a fixed portion and a sliding member that cooperate to define a groove. Movement of the sliding member changes a width of the groove. The clutch further includes a disk having a first edge disposed on the hub and a second edge disposed in the groove. The disk frictionally engages between the hub and the carrier when the clutch is locked. The sliding member is biased such that the groove has a first width for a first range of torques between the disk and the groove and a second width that is greater than the first width for a second range of torques between the disk and the groove that is greater than the first range of torques.

A wedge clutch imparts a wedging effect to selectively transfer power through powertrain components. The wedge clutch includes a hub configured to rotate about an axis and having a tapered hub surface. A rotatable member is configured to rotate about the axis. A plurality of wedge segments are arranged annularly about the axis and are disposed radially between the hub and the rotatable member. The wedge segments can collectively radially expand and contract to lock and unlock the clutch. Each wedge segment defines an aperture therethrough. A cage assembly includes a plurality of pins that each extend through a respective one of the apertures to control relative radial movement of the wedge segments.

A clutch includes a hub and a carrier supported for rotation about a common axis. The carrier has a fixed portion and a sliding member that cooperate to define a groove. Movement of the sliding member changes a width of the groove. The clutch further includes a disk having a first edge disposed on the hub and a second edge disposed in the groove. The disk frictionally engages between the hub and the carrier when the clutch is locked. The sliding member is biased such that the groove has a first width for a first range of torques between the disk and the groove and a second width that is greater than the first width for a second range of torques between the disk and the groove that is greater than the first range of torques.

A clutch for an automatic transmission includes a clutch pack having a first set of friction disks interleaved with a second set of friction disks. The clutch further includes an annulus having an outer surface connected to the first friction disks and an inner surface. The annulus defines oil holes extending from the inner surface to the outer surface to permit oil to flow from the inner surface to the clutch pack. Air passageways are defined in the annulus and extend through the annulus permitting air to flow from the inner surface to the clutch pack to reduce drag losses between the first and second sets of disks. Each of the air passageways have an entrance that is radially inboard of an entrance of each of the oil holes.

An improved torque converter and lock-up clutch assembly includes a sleeve fixed on the sidewall of the lock-up clutch to extend the depth of the clutch, and thereby allow additional clutch packs to be mounted in the cover. The additional clutch packs increase the torque capacity of the assembly. The sleeve includes an annular groove with a snap ring to retain the clutch packs and backing plate in the lock-up clutch cover.