| 摘要 |
PURPOSE:To reduce the weight of a permanent magnet by a method in which plural cores are integrated on the end portion of the side to be touched by the permanent magnet e.g., a rare earth-cobalt-based magnet. CONSTITUTION:One end of a core 9'' of internal magnet type is shaped into a flat form in such a way that it can wholly contact with a permanent magnet 10'', and thereby the contact area can be increased beyond the conventional ones and the used of magnetic materials having smaller magnetic flux density is made possible. A wide range of magnetic materials can be chosen. To avoid the demagnetization of the magnet 10'' by inverse excitation by the coil 8'', the use of magnets having greater 1Hc is much safer, and also since the thickness of the magnet is desired to be thinner as much as possible from the standpoint of operational characteristics, an SmCO2-based rare earth-Co magnet of an energy product of 18MGOe is used. The weight of the permanent magnet can be greatly reduced as compared with the conventional ones. |
