| 摘要 |
<p>PURPOSE: To prevent pile up of dust particles between a coil plate and coil housing face by settingup a detent pin movable at the center of the coil interior and connecting the coil plate pressed by a spring with an end of the detent pin. CONSTITUTION: The detent plate 28 is rotatably held by a operating stick 23, detent pin 30 is movably set up in the interior of the magnetic coil 29, a coil plate 32 pressed by a spring 33 is connected with one end of the detent pin 30, By this structure, while the detent pin 30 is pressed in the interior of the magnetic coil 29, the coil plate 32 trends against the spring 33 and to move away from magnetic coil 29, the spring 33 keeps the coil plate 32 in the normal position without regard to if there is a electric current passing through the coil 29, so pile up of the dust particles between the coil plate 32 and magnetic coil face is prevented.</p> |
