Patent ID: 7815533

Claim:
A camshaft drive system for an internal combustion engine, comprising: a drive sprocket fixed upon a crankshaft of said engine; a driven sprocket fixed upon a camshaft of said engine; a flexible power transmission element extending between said drive sprocket and said driven sprocket, with said power transmission element having a slack side and a tight side; and a tensioning device for said flexible power transmission element, with said tensioning device comprising: a single linear actuator having an axis of operation which is parallel to a line extending from the center of said drive sprocket to the center of said driven sprocket; a plurality of movable contactors for engaging and thereby tensioning said slack side and said tight side of said flexible power transmission element, with each of said plurality of contactors being connected with, a single bridge, slidingly movable by said single linear actuator in the direction of movement of said single linear actuator such that movement of said single bridge and said single linear actuator in a selected direction along said axis of operation will cause said slack side and said tight side of said flexible power transmission element to be displaced equally; and a plurality of stationary contactors rigidly mounted adjacent to said flexible power transmission element, with at least one of said stationary contactors bearing upon said slack side of said power transmission element, and at least another one of said stationary contactors bearing upon said tight side of said power transmission element, such that the travel of said plurality of movable contactors needed to remove slack from said power transmission element is reduced.