A torsional damper is provided and is equipped with a hub fixed to a rotary shaft and having an outer circumferential surface circumferentially around the rotary shaft, an annular vibration ring having an inner circumferential surface circumferentially around the rotary shaft and with a diameter larger than that of the outer circumferential surface of the hub, and a rubber ring in a compressed state between the outer circumferential surface of the hub and the inner circumferential surface of the vibration ring, that is formed from a rubber composition containing EPDM as a main component, and has a loss coefficient (tan δ) of 0.18 or more when the surface temperature is 60±5° C., wherein when subjected to a resonance point tracking method, the maximum attained surface temperature (Tmax) of the rubber ring during continuous excitation at the resonance point and the rubber fitting width (b) satisfy a specific relational expression.

Pulley-torsional damper integrated group comprising a hub adapted to be rigidly connected to a drive member and a pulley connected to the hub. The hub comprises an inner tubular wall and an outer tubular wall. The pulley is angularly coupled to said hub by means of the ring made of elastomeric material. The elastomeric ring has an outer surface towards the pulley and an inner surface towards the hub, and an adhesive is arranged on at least one of the outer or inner surfaces.

An isolator decoupler comprising a shaft, a pulley journalled to the shaft, a one-way clutch engaged with the shaft, a spring carrier engaged with the one-way clutch, the spring carrier having a spring carrier surface, a torsion spring having a first end laser welded to the pulley and a second end laser welded to the spring carrier, the torsion spring having a volute with a width w, an annular spring support member having a spring support member outside surface, the annular spring support member independently moveable from the spring carrier and independently moveable from the shaft, a gap g between the annular spring support member and the spring carrier, the gap g being less than the width w, the first end comprising a first end coil, the first end coil bearing upon the spring support member outside surface, the first end coil laser welded to the spring support member outside surface, a torsion spring radial contraction limited by engagement with the spring carrier surface, and the gap g and the width w have a relationship (w−2r)>(g+c1+c2) were g>0.

A belt pulley structure of an engine is provided to prevent abnormal noise from generating between a belt pulley and a torsional vibration damper. The belt pulley structure includes a stepped portion that is formed in a shape that blocks a cavity in a radial direction thereof. The cavity is formed at a portion where a belt pulley and a torsional vibration damper face each other.

A filtering pulley assembly for an accessory drive of a vehicle has a hub fixedly attachable to a rotating shaft, a pulley mounted coaxial and freely rotating on said hub, an actuator disc carried by the hub, a plurality of elastic assemblies interposed between the pulley and the actuator disc, and a torque limiting coupling configured to rotationally connect the actuator disc to the hub, when the torque is below a predetermined threshold value, and to decouple the actuator disc from the hub, when the torque is above the threshold value.

The invention discloses a novel method for constructing a torsional vibration damper where the spring damper system is aligned axially with the axis of the device, and it is put into compression by axially reducing its width and simultaneously preventing radial expansion. The assembly of the torsional vibration damper occurs in two progressive controlled stages by torquing a set of fasteners, thereby minimizing the shear strain on the elastomer during assembly, enhancing structural robustness, modally stability, and serviceability in the field.

A follower bearing includes an outer ring, rolling elements, and a cage retaining the rolling elements. The outer ring includes an annular first member made of steel, and an annular second member made of resin and covering an outer circumferential surface of the first member. The first member includes a tubular portion. The second member includes a first portion disposed on one side of the tubular portion in an axial direction and having a first opposing surface that opposes an outer circumferential surface of the cage in a radial direction, and a second portion disposed on the other side of the tubular portion in the axial direction and having a second opposing surface that opposes the outer circumferential surface of the cage in the radial direction. In the radial direction, the first and second opposing surfaces are each disposed on a more outer circumference side than a second raceway surface.

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.

In an aspect, an isolation device is provided for a belt and a component shaft in an engine. The device includes a hub, a pulley, an isolation spring and a damping member that is fixed rotationally relative to the hub and is engageable frictionally with the pulley. Torque transmission through the spring below a selected non-zero torque, irrespective of hub load on the pulley, drives a change in radius of the helical coils of the spring that is sufficiently small that the spring avoids pressing the damping member against the pulley. Torque transmission through the spring above the selected non-zero torque, irrespective of hub load on the pulley, drives a change in radius of the helical coils that is sufficiently large that the isolation spring applies a radial force to press the damping member against the pulley so as to generate frictional damping.

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.