Hydraulic tensioner e.g. for i.c. engine transmission chain has non-return valve formed by axially-moving shutter over feed channel outlet

摘要

The tensioner (1) consists of a body (2) with an inner cylinder (3) containing a hollow piston (5) with a high-pressure chamber (C) linked to a pressure source (P) via a non-return valve. The valve is in the form of an axially-moving shutter (17) located in a space (E) facing the outlet end of the fluid feed channel (24). The space is linked to the chamber (C) via an aperture (15a) of greater diameter than the shutter, fitted with a cross-shaped retaining element and located in a plate (15) adjacent to the end of the piston and acting as a thrust plate for a spring (16) inside it.