RING TYPE MAGNET AND ITS MANUFACTURING METHOD

PROBLEM TO BE SOLVED: To provide a ring type magnet which has small decrease in magnetic characteristics due to an orientation disorder near a laminated interface of a laminated preformed element, which has a good shape accuracy, and which can be rotated at a skew angle and laminated of a recess part or a protrusion part formed in a peripheral surface of a radial direction of a ring and to provide a method for manufacturing the same. SOLUTION: The method for manufacturing the ring type magnet includes a step of forming the recess part 1a and the protrusion part 1b on the peripheral surface of a plurality of laminated ring-like preformed elements 2 in the radial direction, a step of forming a recess at a predetermined position of laminating direction end face of the adjacent one preformed element 2 of the preformed element 2, a step of forming a protrusion to be engaged with the recess of the laminating direction end face at a position deviated by a predetermined angle from the predetermined position in a circumferential direction on the laminating direction end face of the adjacent other preformed element 2, and a step of rotating and laminating the recess part 1a or the protrusion part 1b of each of the plurality of the preformed elements 2 by engaging the recess with the protrusion. COPYRIGHT: (C)2005,JPO&NCIPI