| 摘要 |
PURPOSE:To gather magnetic flux generated from a permanent magnet in magnetic flux gathering projections and thereby increase a magnetic flux density by burying the permanent magnet which is magnetized in a plurality of poles in a rotor iron core and installing the sector-form magnetic flux gathering projections whose central angle is smaller than that of one pole of the permanent magnet and which are extended from an outer surface of the rotor iron core. CONSTITUTION:A first rotor iron core 1a is made by forming four magnet fixing holes 3 in a disc-like electromagnetic steel plate which has four magnetic flux gathering projections on an outer surface and has a shaft hole at the center. A second rotor iron core 1b is formed in the same manner as the first rotor iron core 1a except that connections between the magnet fixing holes 3 are cut and the iron core is divided into four magnetic flux gathering projections and one rotor yoke section. A rotor iron core 6 is made by laminating a plurality of the second rotor iron cores 1b and then laminating a plurality of the first rotor iron cores 1a on both end faces of the laminate of the second rotor iron cores 1b. Then, a permanent magnet 7a, 7b is magnetized in N poles and S poles and then is inserted into the magnet fixing holes 3 and then is fastened there. |
