| 摘要 |
PURPOSE:To prevent lowered attraction by providing a cylinder chamber fitted with a piston, which can be driven at proper times, to an extension pipe and a through-hole opened at one end into the cylinder chamber and opened at the other end to the surface of an electromagnet to be detained to an armature. CONSTITUTION:The piston 41 is previously pulled into the upper part of the cylinder chamber 40 via a piston rod 44 by a driving device built into the extension pipe 32 and the coolant immersed with the electromagnet 33, etc., is filled up to the cylinder chamber 40 via the through-hole 39 in said extension pipe. The coolant filled in the cylinder chamber 40 runs through the narrow spacing where the electromagnet 38 and the armature 36 faces each other from the lower aperture of the through-hole 39 so that the coolant is discharged by the route shown by arrows, if the piston 41 is so driven as to be pushed downward where the electromagnet 38 is brought near to the armature 36. The armature 36 is attracted to the electromagnet 38 without intervening any foreign matter at all between the armature 36 and the electromagnet 38 if the electromagnet 38 is thereafter energized. The lowered attraction is thus prevented. |
