| 摘要 |
<p>PURPOSE:To decrease the number of parts and make the assembling work easy, by a method wherein a plate plunger is used and a permanent magnet is disposed to the side of a coil frame in the plate thickness direction. CONSTITUTION:A yoke 11 is abutted to side of a coil frame 13 and recesses 12(a), 12(a)' of an intermediate yoke 12 are fitted to a projection 11(a) thereby the yoke 11 is combined with intermediate yokes 12, 12'. An end surface yoke 21 is abutted to both ends of the yoke 11 and also to end of the coil frame 13 thereby magnetic circuit is constituted and a plunger 14 is inserted to a hole at the center of the yoke 21 and the coil frame 13 thus a polarized solenoid is formed. Solid line represents magnetic flux by permanent magnets 20, 20' and broken line does flux by a coil 19. In this state, flux of the permanent magnets and flux of the coil are superposed at an air gap A and flow in opposite directions to each other at an air gap B. Consequently, at the gap A the magnetic flux is increased and the attractive force increased, whereas at the gap B the magnetic flux is decreased and the attractive force decreased, thus the plunger 14 is attracted towards the gap A. If the coil excitation is reversed, the plunger is attracted towards the gap B.</p> |
