Patent ID: 6609985
Filing Date: 2003-08-26
Classification: F16H

Abstract:
A power transmission chain and tensioner system for an automotive engine application, said chain tensioner and power transmission chain system comprising:a plurality of sprockets including at least one driving sprocket connected to a power input and at least one driven sprocket connected to a power output; a chain wrapped around the plurality of sprockets, the chain including at least a first strand portion having some of links being pulled by the driving sprocket and a second strand portion having some links pulling the driven sprocket; and a chain tensioner including: (i) a shoe having one end movably supported upon a stationary support surface and including a friction surface positioned in contact with at least one of the chain strands to exert force on the strand sufficient to provide tension in the chain, (ii) a blade spring operatively engaging and providing tension on the shoe, as a blade spring and shoe assembly, (iii) a piezoelectric strain actuator element operatively coupled to the blade spring and shoe assembly, and (iv) a circuit adapted to receive sensor signals generated by a sensor element coupled to the blade spring and shoe assembly, wherein the circuit interacts with the piezoelectric strain actuator element to induce a vibratory moment therein effective to dissipate the vibration sensed in the chain tensioner when a sensor signal is received by the circuit that is associated with a vibration occurring in the blade spring and shoe assembly at a predetermined frequency or in a predetermined frequency band.