Abstract: The subject of the invention consists of an overhead valve control for internal combustion engines provided with at least three valves per cylinder controlled through at least one overhead camshaft (1). The control is designed simultaneously to control two mated and parallel valves (3), and is so shaped as to be actuated by a variable profile cam (2).

Abstract: In an internal combustion engine having shafts with variable-profile cams, a tappet system is used which includes an oscillating shoe with a flat, rectangular contact surface, a shoe-carrying saddle having an anti-rotation guide and shoulders for containing the shoe, and a cup in which the shoe-carrying saddle is inserted.

Abstract: In a hydraulic tappet including two cups slidable one within the other, of which the outer one cooperates with the surface of the cam of the camshaft through an adjustment disc while the inner one bears on the end of the valve stem, an expansion chamber is defined between the facing frontal walls of the two cups and is connected to the lubrication circuit of the engine through a supply duct controlled by an oleodynamic valve. The valve is constituted by a conical seat formed in a through-hole in the frontal wall of the inner cup to connect the expansion chamber to the lower part of the cup and intercept the supply duct, and a mushroom-shaped member whose head controls the conical seat and whose stem is inserted in the through-hole which acts as a guide for it.

Abstract: Regulating device with a hydraulic piston sliding inside a chamber and connected integral with a variable-profile camshaft on the side subjected to the axial strain exchanged between the shaft and respective tappets; the device also being provided with a bush and grooved recess arrangement for connecting the chamber selectively to a pressure fluid supply duct or drain duct, and a centrifugal regulator fitted on to the camshaft for controlling the movement of the bush in the recess.