| 摘要 |
Variable control device for an internal combustion engine valve with a stem 1, comprising a cam 2a carried by a shaft of the engine and capable of pushing, either the end of the stem 1, or a boss of an intermediate piece, a finger 3 interposed between the cam 2a and the stem 1 and mounted so as to oscillate about a pin 4 parallel to the shaft, the cam 2a having a lobe projecting from a primitve circular periphery and the finger 3 possessing a first rectilinear face 5 interacting with the stem 1 and a second face 6 turned towards the cam 2a comprising an inclined portion 7, characterised in that the second face 6 has, on the side of the pin 4, a rectilinear portion 8 parallel to the first face 5, and on the other side of the cam 2a a curved portion 9 with concavity turned towards the cam 2a, connecting the portion 8 to the portion 7, the latter being separated from the face 5 by moving away from the pin 4, and means are provided for placing the pin 4 alternately at low speed of the engine in a position where the cam 2a interacts solely with the portion 8, and at high speed of the engine in a position more distant from the stem 1 where the cam 2a interacts successively with the three portions 8, 9, 7 of the face 6 via its circular periphery or via its lobe. This arrangement makes it possible to vary the lifting law of the valve as a function of the speed of the engine. <IMAGE>
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