Patent ID: 6808467
Filing Date: 2004-10-26
Classification: F16H

Abstract:
A blade tensioner for a chain that drivingly connects a driving shaft in an engine to a driven shaft of the engine, the blade tensioner comprising:a) a blade shoe having an arcuately curved chain sliding face; b) a proximal end portion provided at a proximal side of the shoe, arranged to rotate freely around a support shaft mounted on the engine and inserted therethrough; c) a distal end portion provided at a distal end of the shoe, for sliding freely along a support face provided in the engine; d) a plurality of blade springs disposed opposite the chain sliding face of the blade shoe, for exerting a spring force on the blade shoe; the chain sliding face having a longitudinal dimension parallel to the chain, and a width between sides greater than a width of the chain, a guide portion extending continuously along each of the sides of the chain sliding face for guiding the chain sliding along the chain sliding face between the guide portions, the guide portions having a height, a plate thickness, and a cross-sectional shape selected such that a flexural rigidity of the blade shoe is not increased; wherein the guide portions (17) are provided in a region that includes a contact start location (A) and a separation start location (B); wherein the contact start location and the separation start location of the guide portions, have heights (hA) and (hB) respectively, and the height in an intermediate section between the contact start location and the separation start location of the guide potions is (hC), resulting in relationships hC&gE;hA and hC&gE;hB.