A system for bypassing a torque converter in a powertrain is provided. The system includes a torque generating device including an output shaft and a transmission assembly. The transmission assembly includes a transmission output shaft and a torque converter, a torque converter bypass shaft. The transmission assembly further includes a disconnect clutch selectively coupling the torque converter with the torque generating device and a torque converter clutch selectively coupling the torque converter bypass shaft with the torque generating device. Engaging the disconnect clutch and disengaging the torque converter clutch enables the torque generating device to transmit torque to the transmission output shaft through the torque converter. Engaging the torque converter clutch and disengaging the disconnect clutch enables the torque generating device to transmit torque to the transmission output shaft through the torque converter bypass shaft.

A clutch that includes a friction plate; a separator plate; a clutch hub; and a piston that presses the friction plate and the separator plate, wherein the clutch hub includes a hub on which an inner peripheral portion of the friction plate or the separator plate is fitted, a tubular shaft that movably supports the piston, and an engagement oil chamber defining wall that together with the piston defines an engagement oil chamber to which an engagement oil pressure is supplied, the hub is spline-fitted on a gear of a planetary gear so as to rotate with the gear, and the tubular shaft is rotatably supported by a central shaft and is fitted by a spigot joint in the gear.

A hydrodynamic coupling arrangement has a housing connected to pressure medium lines for conducting pressure medium into or out of a pressure space sealed by a piston of a clutch device relative to a toroidal space of a hydrodynamic circuit provided in the housing. A rotatable area is provided for axially displaceably receiving a radially inner piston hub of the piston of the clutch device, and at least one through-opening which is rotatable relative to the housing is provided in a through-opening area for producing at least one flow connection between at least one pressure medium line and the pressure space. The receiving area and the through-opening area are in rotational communication with a retarding device influencing a flow of pressure medium in the pressure space, this flow of pressure medium arriving in the pressure space after passing through the through-opening area.

An intermediate member of a damper device includes a plate portion that has spring abutment portions that abut against inner springs. Spring abutment portions of a coupling member of a dynamic damper extend from a fixed portion via a bent portion to be disposed in opening portions of the plate portion, and abut against end portions of third springs disposed in the opening portions such that the third springs are arranged side by side with the inner springs in the circumferential direction. The plate portion and the spring abutment portions at least partially overlap each other in the thickness direction. The axes of the inner springs and the third springs are included within the range of overlap between the plate portion and the spring abutment portions in the thickness direction.

A torsional vibration damping arrangement, in particular mass damper subassembly, having a carrier which can be driven in rotation and a damper mass rotatably deflectable with respect to the carrier against the restoring action of a substantially radially extending damper spring. The damper spring is fixedly clamped in the damper mass and is supported or supportable with respect to the carrier for transmitting circumferential force. The damper spring is clamped between clamping elements arranged at both sides of the damper spring in circumferential direction.

A clutch arrangement is provided with a mass damper system having a damper mass carrier and damper masses deflectable relative to the damper mass carrier. The clutch arrangement has a housing having at least two housing parts permanently connected to one another by a fixed connection, at least one housing parts has a cutout for at least one projection of the other housing part. The housing parts are assembled while receiving the damper mass carrier between an axial stop of the cutout of the one housing part and the projection of the other housing part. The housing parts are loaded over the course of producing the fixed connection by a clamping mechanism which acts on the housing parts in direction away from one another and operative axially between one of the housing parts and the damper mass carrier axially supported at the other respective housing part.

If the difference between output torque output from an engine and load torque from drive wheels is large and torque input to a lockup clutch is large, since a value of lockup command pressure at which lockup engagement pressure in lockup end control becomes constant standby pressure is set to be high, fast release of the lockup clutch or racing of the engine is suppressed during the lockup end control. If torque input to the lockup clutch is small, the value of the lockup command pressure at which the lockup engagement pressure in the lockup end control becomes the constant standby pressure is set to be low, and a hydraulic pressure output period during which hydraulic pressure is output to the lockup clutch is set to be short.

A torque converter that is downsized in an axial direction utilizing existing space is provided. A pump impeller, a turbine runner, a lockup clutch, an elastic damper, and a planetary unit are held in a housing. A torsional vibration damping device is arranged concentrically with the lockup clutch. An input element is arranged concentrically with the lockup clutch while being connected to the lockup clutch and a drive member. An output element is connected to a driven member.

An electronic control unit performs lockup clutch engagement control in the sequence of fast fill control, constant-pressure standby control and command pressure raising control, and starts the lockup clutch engagement control from that one of the fast fill control and the command pressure raising control which is later in sequence than the other, as a command pressure for a control oil pressure at a transition time point for making a transition to the lockup clutch engagement control rises, in making the transition to the lockup clutch engagement control during the lockup clutch release control. Therefore, when the command pressure for the control oil pressure is equal to or higher than a predetermined value that is needed to carry out packing for narrowing a pack clearance of a lockup clutch, the lockup clutch engagement control is started from the command pressure raising control.

An output rotary member is coupled to a turbine and rotatable relatively to a clutch portion. First elastic members elastically and rotation-directionally couple the clutch portion and the output rotary member. A dynamic damper device is coupled to any of members forming a power transmission path from the clutch portion to the output rotary member and includes a damper plate having a plurality of circumferentially extending first openings and to be rotated together with the output rotary member. The dynamic damper device also includes inertia members disposed on both axial sides of the damper plate and rotatable relatively to the damper plate, each of the inertia members having circumferentially extending second openings located to oppose the first openings. The dynamic damper device further includes second elastic members accommodated in the first openings and the second openings, the second elastic members elastically coupling the damper plate and the inertia members.