Patent attributes
A device for controlling the variation of the opening and closing times and durations of a valve (8) comprises an elastic means (18) acting upon an assembly consisting of a lever device (1) and a valve stem (11) not in the closing direction but in the opening direction of the valve (8). The assembly consisting of the lever device (1) and of the opening cam (5) and the closing cam (6) fulfils a dual function, one for opening the valve (8), the other for moving it back for its closure. The control device, which comprises a device for offsetting the angular position of the cam position relative to the crankshaft, allows to control the opening and closing duration of the valve (8) over a very wide range extending, for opening, from 210° to 350° of crankshaft rotation approximately, by varying the valve opening and closing times independently of each other. It is applicable to a wide range of engines.