Abstract: A belt tensioner having a tensioner arm swingably connected to a stationary member about a swing shaft and a belt engaging member for engaging a belt and rotatably arranged at the tensioner arm. A first urging member urgings the tensioner arm rotationaly around the swing shaft so that the belt engaging member tensions the belt. A damping member arranged between the stationary member and the tensioner arm so that friction is produced between the stationary member and the damping member in order to damp a swinging motion of the tensioner arm when the tensioner arm swings. A second urging member urges the damping member toward the stationary member or vice versa in order to produce the friction.

Abstract: A toothed power transmission belt comprising a body, transversely extending teeth positioned along at least one face of said body, and an inextensible tensile member embedded in said body, the material of said body comprising a blend of an epihalohydrin having a nominal Mooney viscosity of not more than 50 and an epihalohydrin having a nominal Mooney viscosity of not less than 50.