Blade-type chain tensioner system

A blade-type tensioner system for a chain, the system including a blade-type tensioner imparting tension to the chain that drivingly connects a driven shaft to a drive shaft in an engine, the blade-type tensioner comprising:

• a blade shoe having a shoe body with an arcuately curved chain sliding face, a proximal end portion provided on a proximal side of the shoe body, wherein the proximal end portion of the blade shoe is pivotably supported around a supporting shaft inserted into the proximal end portion, and a distal end portion provided on a distal side of the shoe body;
• a blade spring for imparting tension to the chain through the blade shoe, the blade spring being positioned on a back side of the chain sliding face of the blade shoe;
• a first supporting face and a second supporting face provided in the engine so as to slidably support the distal end portion of the blade shoe, the second supporting face having a circular, concave surface that is continuous with the first supporting face;
• and
• wherein the distal end portion of the blade shoe has a circular, convex surface adapted to contact the first or second supporting face, the circular, convex surface of the blade shoe being slidably supported on the first or second supporting face in the engine, such that the circular, convex surface of the distal end portion may contact the second supporting face when tension in the chain is increased.