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.

A filtering pulley for an accessory transmission of an internal combustion engine that has a hub, a crown, a filtering unit or transmitting the torque interposed between the hub and the crown, a torsion spring, a carrier, and a torque limiting joint. The torque limiting joint is coupled to interface with one of the surfaces between the crown and has an open-loop strip spring. The torque limiting joint and is configured to slide with respect to said surface when the torque transmitted between the crown and the hub reaches a predetermined level.

Pulley assembly (111) comprising a hollow shaft (112) with an axis X, the hollow shaft (112) being suitable for being mounted on a shaft of a rotating electrical machine, the hollow shaft comprising at least one thread or tapping (132, 133) and a collar (113) extending radially outwards, wherein said hollow shaft also includes: a nut (128, 129) screwed on the hollow shaft via the thread or tapping; a spring (126) mounted about a portion of the nut; at least one ball bearing (122, 123) tightly fitted to the hollow shaft; a pulley (130), tightly fitted to said at least one bearing, about the spring, the nut and the hollow shaft. The nut (128, 129) includes a radial shoulder (131) mounted between the spring (126, 127) and the ball bearing (122, 123), the spring being held axially between the collar (113) and the radial shoulder (131).

A structure for belt installation of an engine for a vehicle is provided. The structure includes a damper pulley that is mounted to a crankshaft of the engine and a stretch belt that has a first end mounted on the damper pulley and a second end connected to an upper portion of a pulley portion of an accessory. The accessory is mounted on the engine at a position spaced apart from the damper pulley. The pulley portion includes a guide member on a front center thereof which guides installation of the stretch belt to the pulley portion.

An isolator comprising a pulley having a pulley stop, a plate attached to the pulley, a shaft, the pulley journalled to the shaft, a torsion spring attached to the shaft, a damping member attached to the torsion spring, the damping member disposed between the plate and the pulley, and the damping member compressing a damping fluid against the pulley stop.

An isolator comprising a pulley and a shaft, the pulley journalled to the shaft, a load stop, a torsion spring, a damping member attached to the torsion spring, the damping member disposed between the load stop and the torsion spring, and the damping member compressing a damping fluid against the load stop; where the load stop is attached to the pulley or the shaft and the torsion spring is attached to the shaft or the pulley, respectively.

A power transmission device includes an electromagnet, a rotor, an armature and a hub that couples the armature to a shaft of a driving target device. The hub includes an outer hub coupled to the armature, an inner hub coupled to the shaft, and an elastic member interposed between the outer hub and the inner hub. An outer peripheral side of the inner hub includes plural extending parts each extending outward in a radial direction. An inner peripheral side of the outer hub includes an inner peripheral side wall that overlaps with the extending parts in a rotational direction and surrounds the extending parts. The elastic member is disposed in an unbonded state with respect to at least one of the inner hub and the outer hub between the outer peripheral side of the inner hub and the inner peripheral side of the outer hub.

A pulley decoupler for an accessory drive comprises input and output parts. The output part and the input part are rotatable about a common axis of rotation and are rotatable to a limited extent relative to one another. A centrifugal pendulum device is provided for damping torsional vibrations with a centrifugal pendulum flange that can be rotated about the axis of rotation and has at least one pendulum mass displaceable under centrifugal force relative to the centrifugal pendulum flange. The at least one pendulum mass is acted on by a friction force generated by a first friction device having a first spring and at least one first friction element.

A belt tuning device to an accessory belt drive system (ABDS) that utilizes a torsional spring to connect the belt pulley to the shaft of a motor generator unit to isolate the system and allow the pulley to advance ahead of the motor or to be behind the motor. The tuning device also has a free running zone providing a decoupling function for the system, allowing the tuning device to be both a driver and a generator of power. The tuning device has all of the belt pulley, a spring retainer, a torsion spring, a stop ring, and a shaft fixed in relation to each other.

In an aspect an isolation device is provided, comprising a hub that is connectable to a shaft; a pulley that is rotatable relative to the hub; at least one isolation spring positioned to transfer torque between the hub and the pulley, wherein each of the at least one isolation spring is an arcuate helical compression spring having an isolation spring axis that is arcuate; and a spring shell that is monolithic and that receives the at least one isolation spring and transfers torque between the at least one isolation spring and the pulley. The spring shell surrounds more than 180 degrees of the at least one isolation spring in a plane that is perpendicular to the isolation spring axis.