Torsional vibration dampers having a dual spring-dashpot system are disclosed that result in a lightweight hub and a lightweight inertia ring, which is concentric about the hub. The hub has a two-piece construction: a central hub defining an innermost sleeve that defines a bore for receiving a shaft; and a monolithic, generally-annular spoke defining an outermost ring concentric about and spaced radially outward from the central hub portion. A first elastomer member, which acts as a primary spring to damp torsional vibrations, is positioned concentrically against an inner surface or an outer surface of the outermost ring of the hub with the inertia ring concentrically positioned against the first elastomer member. A second elastomer member is positioned between and operatively couples the central hub to the annular spoke, thereby attributing a flexibility to the hub.

A pulley structure includes: a cylindrical outer rotation body; an inner rotation body; and a torsion coil spring. The torsion coil spring includes: one end region which is in contact with one rotation body; the other end region which is in contact with the other rotation body; and a middle region. The other rotation body includes: a first contact surface; a facing surface; an inclined surface; and a second contact surface. The facing surface includes a constraining surface connected to the inclined surface. The constraining surface is configured to be capable of constraining the other end region of the torsion coil spring before press fitting so as to prevent a displacement of an axis of the torsion coil spring before the press fitting with respect to an axis of the other rotation body.

A sealing structure with a torsional damper and an oil seal includes a damper pulley and an oil seal. The damper pulley includes, in a disk part of a hub on a front cover side, an annular projection that protrudes between the window and the boss part. The oil seal includes a side lip and a flange. The side lip extends to the inside of an annular groove of the damper pulley. The flange is opposed to the projection of the damper pulley to cover the projection so that a gap is formed between the flange and the projection.

A torque filter having an impact spring constant includes a pair of left and right arc springs arranged at left and right sides and having spring constant values set based on a torque of a crank shaft which transfers a driving force of an engine as the torque. An impact spring is disposed in which the pair of the left and right arc springs face each other and has a spring constant value set with a threshold torque based on an instant speed change of the crank shaft.

The present invention relates to a decoupler with free wheel system and comprising a vibration damping pulley, a shaft actionable by the pulley, hub pieces having a first hub piece and a second hub piece, hub pieces being mounted between the inner race of the pulley and the outer surface of the shaft, at least one journal element between the shaft and pulley, along with a torsion spring, and a clutch spring, with the first hub piece being mounted on the shaft and the second hub piece being mounted around the shaft and can rotate relative to it, the torsion spring being disposed between the outer race of the hub pieces and the inner race of pulley, having a first end operatively attachable to the pulley and a second end operatively attachable to the second hub piece and the clutch spring being disposed internally in relation to the torsion spring and which is frictionally engaged with the hub pieces for transmission of torque to the shaft.

A method for applying a coating to a substrate includes obtaining a fluorinated polymer compound, where the fluorine is chemically or covalently bonded to the polymer molecule; and coating the surface of the substrate with the fluorinated polymer compound.

A sealing structure with a torsional damper and an oil seal includes a damper pulley serving as a torsional damper and an oil seal. The damper pulley has an annular hub pocket that is recessed in the outer side direction and extends in the circumferential direction along a boss part of a hub. The oil seal includes a side lip that extends toward the outer side. An outer circumferential surface of the hub pocket increases in a diameter toward the outer side, the side lip of the oil seal does not enter inside the hub pocket, and an annular gap is formed between an outer side end of the side lip and an inner side end of the outer circumferential surface of the hub pocket.

An accessory drive tuning device with a torsion spring for angular vibration isolation and having a spring pocket that frictionally engages the end of the torsion spring. The engagement may be with a wedge-shape on either the spring end or the pocket or both, adapted so that the spring end wedges into the pocket. The engagement may be by interference fit. One or both ends of the spring may be engaged in respective pockets.

An isolating decoupler comprising a shaft, a pulley journalled to the shaft, a torsion spring, the torsion spring comprising a flat surface planar in a plane normal to the rotation axis A-A on each end of the torsion spring, a one-way clutch engaged between the torsion spring and the shaft, a weld bead joining a torsion spring end to the one-way clutch, and a weld bead joining the other torsion spring end to the pulley.

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 5 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 10 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.