PRODUCTION METHOD FOR PERMANENT MAGNET, PRODUCTION DEVICE FOR PERMANENT MAGNET, PERMANENT MAGNET AND ROTATING ELECTRICAL DEVICE

摘要

In a production method for permanent magnet, a magnetic powder is loaded into a cavity formed in a groove shape whose longitudinal direction horizontally extends. A loading step of loading the magnetic powder includes a first loading step of loading, of the magnetic powder, a first magnetic powder containing no heavy rare earth element or containing a heavy rare earth element, and a second loading step of loading, of the magnetic powder, a second magnetic powder having a higher content rate of heavy rare earth element than that of the first magnetic powder, at a predetermined position in the cavity.

主权项

1. A production method for permanent magnet, comprising:
a loading step of loading a magnetic powder into a cavity formed by a mold; and a pressurizing step of pressurizing the magnetic powder in the cavity, thereby compressing and molding the magnetic powder, wherein the cavity is formed in a groove shape such that a longitudinal direction of the cavity extends in a horizontal direction, and the loading step includes
a first loading step of loading a first magnetic powder of the magnetic powder,a second loading step of loading, of the magnetic powder, a second magnetic powder at a predetermined position in the cavity, a content rate of the heavy rare earth element in the second magnetic powder being higher than that in the first magnetic powder,a first closing step of, before the pressurizing step and after the first loading step, closing the cavity with a first lid portion which has a preliminary molding portion with a protrusion formed at the predetermined position at a cavity side, and depressing the first magnetic powder in the cavity by the preliminary molding portion, thereby transferring a shape of the preliminary molding portion and molding the first magnetic powder in which a dent is formed at the predetermined position, anda second closing step of, after the second loading step, closing the cavity with a second lid portion (223b) which has a molding portion at the cavity side, and depressing the magnetic powder in the cavity by the molding portion, thereby transferring a shape of the molding portion and molding the magnetic powder.