摘要 |
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 permanent magnet (4) is coupled to an intake or exhaust valve (7), a first electromagnet (3) is provided to be opposed to one end in the reciprocating direction of the moving permanent magnet (4), a second electromagnet (5) is provided to be opposed to the other end, and the intake or exhaust valve (7) is opened and closed by the electromagnetic attractive and repelling forces that act among the moving permanent magnet (4), the first electromagnet (3) and the second electromagnet (5). The force for opening and closing the intake or exhaust valve (7) can be changed by controlling the condition of flowing currents to the first electromagnet (3) and to the second electromagnet (5). Therefore, the timings are controlled to open and close the intake or exhaust valve (7) depending upon the operation condition of the engine (1). |