BigPatents India

A hydraulic tensioner for applying tension to a chain comprising a housing, a hollow piston, a spring, and a pawl. The housing has a cylindrical bore and pawl hole. The hollow piston has rack teeth along its length and is slidably received by the bore. The piston and the bore define a fluid chamber within the bore. A spring biases the piston in a protruding direction from the bore. A pawl, received by the pawl hole of the housing has a front surface, a rear surface, and a tooth section biased to engage the rack teeth of the piston by a pawl spring in a pawl spring accommodating section of the pawl hole. A clearance is present between the pawl hole and the front surface and the rear surface of the pawl, to allow longitudinal travel of the pawl. (FIG.1)