A dynamic damper includes a hub, a vibration ring located on the outer periphery of the hub, and a pair of elastic bodies made of a rubber-like elastic body located on both sides in the axial direction of the vibration ring and coupling the hub and the vibration ring, in which the vibration ring is provided with a protrusion extending to the vicinity of the outer periphery of the hub, each of the elastic bodies has a shape of being curved outward in the axial direction from the protrusion from the hub to the vibration ring, a projection extending toward the protrusion is integrally molded on a surface on a protrusion side in the elastic bodies, and a gap is set between the protrusion and the projection.

An isolator comprising a shaft, a pulley journalled to the shaft, a first torsion spring engaged between the shaft and the pulley, a second torsion spring engaged between the shaft and the pulley, the first torsion spring and the second torsion spring wound in opposite directions, the first torsion spring engaged to transmit a first torque in a first direction from the pulley to the shaft, the second torsion spring having a passive engagement with the pulley during transmission of the first torque, and the second torsion spring engaged to transmit a second torque in a second direction from the shaft to the pulley, the first torsion spring having a passive engagement with the pulley during transmission of the second torque.

A viscosity-torsional vibration damper or absorber for a crankshaft of a combustion engine includes an annular damping or absorbing arrangement which can be fastened to the crankshaft. The damping or absorbing arrangement is fastened in an outer diameter region to a holding device which, on the other hand, can be fastened to the crankshaft and can be sprung in the axial direction of the crankshaft, but is inherently rigid radially with respect to the crankshaft.

Filtering pulleys have a hub adapted to be fixed to a rotating shaft, a ring assembled coaxial and rotationally free on the hub, and an elastic assembly arranged circumferentially with respect to the hub and the ring and interposed between a pair of first elements integral with the hub and between a pair of second elements integral with the ring. The elastic assembly includes an elastic element having a progressive rigidity increasing starting from a predetermined threshold value of the angle of relative rotation between the hub and the ring.

A vibration damping device for a belt drive of an internal combustion engine includes a belt pulley, a hub and a decoupling device. The decoupling device connects the belt pulley and the hub to each other, and has at least two spring members. The spring members can be connected in series.

An isolator is provided for use with an engine and in particular an engine that is assisted or started by MGU (Motor-Generator Unit) or a motor through an endless drive member. It comprises a double acting spring system for isolating crankshaft pulley from torsion vibration at the crankshaft, and in extreme conditions, such as during engine startup and accelerations or decelerations of the engine crankshaft relative to the pulley and when isolator operates in an engine-driven mode with the engine crankshaft is driven by the belt.

A multi-axial unidirectional power transmission system includes a transmission unit and a resistance unit. The transmission unit includes a first main shaft and a transmission wheel provided on the first main shaft. The resistance unit includes a second main shaft and a damping wheel mounted on the second main shaft. The two transmission wheels and the damping wheel can be placed flat on the body since they are mounted on different main shafts, thereby making the whole plane of the multi-axis unidirectional power transmission system consistent, thus achieving the effects of space saving, convenient storage and convenient transportation.

A pulley assembly connecting an ISG driveshaft of an ISG and an engine to each other through a belt may include: a pulley member around which the belt is wound; a spring hub fixed to an internal peripheral surface of the pulley member; an ISG hub rotatably disposed when the ISG hub is distanced from an internal peripheral surface of the spring hub by a predetermined interval and connected to the ISG driveshaft; a limit device provided in the spring hub and ISG hub and limiting a rotation of the ISG hub to rotation by a predetermined rotation angle; and a plurality of leaf springs radially inserted into the spring hub in a circumferential direction thereof, and having one end portions fixed to the spring hub and the other end portions penetrating the ISG hub.

In an aspect, the invention is directed to a clutched device that includes a clutch input member, a clutch output member, and a wrap spring clutch. The wrap spring clutch is engageable with the clutch input member and the clutch output member and has a radially outer surface and a radially inner surface. One of the radially outer and inner surfaces is engageable with a clutch engagement surface on one of the clutch input member and the clutch output member. The clutch engagement surface has a surface finish that includes peaks and valleys, wherein the peaks engage the wrap spring clutch and each have a selected width.

In an aspect, a power transfer device, such as a decoupler, is provided for transferring torque between a shaft and a belt. The device includes: a hub configured to couple to the shaft, a pulley rotatably coupled to the hub that includes a power transmitting surface configured to engage the belt, an isolation spring to transfer a rotational load from one of the pulley and the hub to the other of the pulley and the hub, optionally a one-way clutch to permit overrunning of one of the pulley and the hub relative to the other of the pulley and the hub in a first direction, and a damping member positioned to be driven into frictional engagement with a friction surface by a force from the isolation spring acting on the damping member that varies based on the rotational load transferred by the isolation spring.