A timing variator, particularly for changing the relative timing between a camshaft and the timing drive mechanism of an internal combustion engine.

摘要

The timing variator 1 is fitted to the shaft A through a hub 2 adapted to be secured by thread engagement on the end of the shaft A. The assembly of the hub 2 and plunger 5 is surrounded by a case, substantially consisting of a cylindrical shroud 8 which envelops the plunger 5, and of an end cover or cap 9 which closes the shroud 8 on the opposite from the shaft A and receives inside a respective axial blind hole 9a the free end of the hub 2 while also confining, with respect to the homologous end of the plunger 5, an annular chamber 21 to which the conduits 4 open. This constructional approach, additionally to prevent any axial sliding of the case 8, 9 relatively to the hub 2, can give full assurance of the variator case being fully sealed from the oil (servo-medium) being supplied into the chamber 21 without requiring the use of seals. The cap is connected to the shroud 8 so as to form a unitary construction typically by a laser weldment along the outward leg 89 of a toroidal connecting surface having a stepped profile defined by respective complementary shoulders.