Automatic belt tensioner, in particular for timing belts, such as a timing belt for a combustion engine

摘要

Automatic tensioner for a timing belt, particularly for a timing belt for a combustion engine of the "linear with axial thrust" type, comprising a roller (21) capable of interacting with the belt (11) and a device (25) for actuating the said roller having a piston (31) mounted slidingly in a body (30) which defines a pressure chamber (32) and a reserve chamber (33) for a hydraulic fluid, it being possible for the said chambers to communicate with one another through at least one passage in the said piston on which is exerted the action of a compression spring (36) which urges the piston towards the reserve chamber. …??The piston (31) is pierced with a multiplicity of passageways which may be open/closed by a shutter (40) consisting of a valve with an operational part consisting of a flexible lip. …IMAGE…