| 摘要 |
An electromagnet composed of a coil, a movable iron core adapted to move on the center axis of the coil, and a stationary iron core provided so as to cover the upper and lower surfaces and the outer peripheral surface of the coil, characterized by a permanent magnet arranged in a gap surrounded by the movable iron core and the stationary core, wherein the movable iron core is attracted by the stationary iron core by a magnetic field created by the permanent magnet, thereby it is possible to solve a problem inherent to a conventional electromagnet such that a permanent magnet is directly energized in a reverse direction during release operation so as to cause demagnetization of the permanent magnet. That is, since the permanent magnet is arranged in the gap surrounded by the movable iron core and the stationary iron core, the magnetic filed can be prevented from affecting upon the permanent magnet, thereby it is possible to provide an electromagnet having a long use like and a high degree of reliability with no demagnetization of a permanent magnet.
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