| 摘要 |
The device is adapted to control the movement of a valve (1) of an internal combustion engine comprising a stem (1a) which may move in translation through an opening (2a) of a hollow guide body (2) and which ends in a mushroom head (1b) cooperating in operation with a valve seat (12) provided in a wall (13) of the engine head. The valve (1) may move in translation with respect to the hollow guide body (2) between a retracted position and a forward position in which the mushroom head (1b) respectively closes and opens the associated valve seat (12). The control device comprises an electromagnet (3) adapted, when energised, to retain the valve (1) in the retracted closed position, a first spring (7) associated with the valve (1) and tending to urge it towards the open position, and a second spring (8) also associated with the valve (1) and tending to oppose its transition into the open position. The arrangement is such that when the electromagnet (3) is de-energised, the valve (1) moves in acceleration towards the open position under the action of the first spring (7) until the action of the latter stops, and then the valve (1) moves in deceleration into the open position under the action of the second spring (8).
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