| 摘要 |
<p>A valve actuator to open and close the intake and exhaust valves of an engine utilizing the electromagnetic force generated by an electromagnet. A reciprocally moving magnetic pole (6) is coupled to an intake or exhaust valve (9), an upper fixed magnetic pole (3a) is provided to be opposed to an end in the reciprocating direction of the moving magnetic pole (6), an intermediate fixed magnetic pole (3b) is provided to be opposed to one end of the moving magnetic pole (6) and to the upper fixed magnetic pole (3a), and a first tip-fixed magnetic pole (3c) is provided to be opposed to the other end of the moving magnetic pole (6). The intake or exhaust valve (9) is opened by the repelling force that acts between the upper fixed magnetic pole (3a) and one end of the moving magnetic pole (6). Being contiguous to the upper fixed magnetic pole (3a), furthermore, a second tip-fixed magnetic pole (3d) is provided to be opposed to the other end of the moving magnetic pole (6), and the intake or exhaust valve (9) is closed by the attracting force acting between the upper fixed magnetic pole (3a) and one end of the moving magnetic pole (6) that results from the magnetic flux passing through the second tip-fixed magnetic pole (3d). By changing the times for exciting the magnetic poles, therefore, the timings can be controlled to open and close the intake or exhaust valve (9).</p> |
