Patent ID: 7597639

Claim:
An improved power transmission belt tensioner having a pulley adapted to communicate with a surface of a power transmission belt, an arm supporting said pulley upon which said pulley is rotatably mounted via a pulley bearing, a shaft supporting said arm, said shaft rotatably supported by a pivot bearing, an attachment point for a strut, and said strut attached to said attachment point, the improvement comprising: said strut attachment point is laterally opposite of said pivot bearing in relation to the plane of rotation of said pulley; said strut attachment point forming part of a shield extending from a support for said pulley bearing; and said pulley and said attachment point laterally offset in relation to said pivot bearing such that a balance line passing through an axis of said attachment point and a center of said pulley intersects said shaft within a lateral limit of said pivot bearing, thereby substantially balancing said tensioner in terms of parasitic torque across said pivot bearing.