PURPOSE: To achieve three-step changeover and stop of current in an intermediate step and to simplify the structure by flowing the different currents in polarities in an electromagnetic coil to rotate a magnet oppositely to a detent torque and to stop it by stoppers.
CONSTITUTION: Under the condition that a current does not flow in terminals A, B and C, a permanent magnet 10, magnetic poles of the permanent magnet 10 are different in a circumferential direction and a diameter of an insertion hole 8 is different in a circumferential direction, so that the magnetic poles of the permanent magnet 10 approach a core 3 as there is a least gap between them. Namely, the magnetic poles of the permanent magnet 10 face subsystems 5a and 5b of the core 3 by the detent torque (the force by which a permanent magnet is attracted to a magnetic substance). If the current flows between the terminals A and B, a magnetic flux loop as shown by the broken line is formed between the core 3 and a housing 1, a main system core 4a becomes N-pole and another main system core 4b becomes S-pole. Accordingly, the magnetic poles of the permanent magnet 10 are attracted by opposite poles of the core side respectively to be rotated in a direction θ1 and the rotation stops when a stopper 21 hits against a projected stopper 22a.
SUZUKI TETSUJI
KONDOU YOSHIAKI
| JPS58212361A | 1983-12-10 | |||
| JPS59191466A | 1984-10-30 |
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