Anisotropic magnet for rotary electric machine

Abstract

An anisotropic magnet for a rotary electric machine having at least two magnetic pole portions in a cylindrical yoke. An anisotropic magnet constituting the magnetic pole portions is arranged such that a central portion of each magnetic pole portion has lines of magnetic force oriented in a radial direction, and opposite end portions of each magnetic pole portion located closer to respective opposite ends of the magnetic pole portion has lines of magnetic force oriented in such a manner as to be gradually offset from the radial direction toward a mutually parallel direction. Accordingly, an effective magnetic flux density of a sinusoidal waveform is generated in the magnetic pole portions. Also disclosed is an apparatus for molding an anisotropic magnet comprising: an upper die and a lower die respectively provided with a recess having an arcuate cross section; a central core whose opposite end portions are each formed into a substantially fan-shaped cross section and which allows a magnetic field to be generated; and two side cores disposed on the sides of said central core, side surfaces of opposite end portions of the side cores being formed into a substantially parallel configuration, said side cores being adapted to generate a magnetic field. Accordingly, the anisotropic magnet thus formed has lines of magnetic force oriented radially in its central portion and oriented substantially in parallel with each other at its opposite end portions.

Dependencies are inferred from the claim text.