| 摘要 |
PROBLEM TO BE SOLVED: To provide an electromagnetic actuator whose consumption power is reduced by reducing air gap and improving electromagnetic efficiency. SOLUTION: When an engine valve 38 is to be opened from a state (A), a current is made to flow in a first coil 8 so as to generate magnetic flux in the direction as shown in (B), in the opposite direction to the magnetic flux, shown by broken lines, which are generated by permanent magnets 14A, 14B. Thereby the attractive force due to the magnetic force of the permanent magnets 14A, 14B is canceled, and a second movable member 24B is moved in the valve opening direction (downward direction) by the energizing force of a third coil spring 4. Although a current is made to flow into a secondary coil 18 at the same time, since the second movable member 24B is slid to the lower side with respect to a first movable member 24A, an air gap with a second core is reduced. Hence electromagnetic efficiency is improved, and current necessary for moving the movable members 24 (24A, 24B) can be made small, so that consumption power of the secondary coil 18 is reduced.
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