Production method for anisotropic bonded magnet and production apparatus for same

A production method for an anisotropic bonded magnet, comprising:

• a filling step that fills an annular cavity with a magnet raw material including one or more types of rare-earth anisotropic magnet powder and a binder resin;
• an alignment step that applies aligning magnetic fields to the magnet raw material in the annular cavity to cause the rare-earth anisotropic magnet powder to be aligned in the binder resin being in softened state or in molten state, the aligning magnetic fields being applied from an even number of aligning magnetic pole bodies arranged uniformly around outer periphery of the annular cavity such that directions of magnetic fields thereof are alternately reversed, each of the aligning magnetic pole bodies having a permanent magnet as a magnetic field source;
• a molding step that subjects the magnet raw material during the alignment step or after the alignment step to a molding to obtain an annular compact;
• and
• a discharging step that discharges the compact from the annular cavity,
• the production method being characterized in that the discharging step is an engaging step that engages the compact into a tubular body while discharging the compact from the annular cavity, the tubular body being provided coaxially with the annular cavity and having an inner peripheral surface capable of being contacted with outer peripheral surface of the compact.

A production apparatus for an annular anisotropic bonded magnet, comprising:

• a hollow cylindrical or solid cylindrical core;
• a mainly molding die that surrounds the core to form an annular cavity therebetween;
• and
• an aligning magnetic pole body that includes an even number of permanent magnets arranged uniformly around and in vicinity of outer periphery of the mainly molding die such that directions of magnetic fields thereof are alternately reversed, the permanent magnets being capable of providing an aligning magnetic field to the annular cavity,
• the production apparatus being characterized by further comprising a driving means that causes the aligning magnetic pole body to relatively move with respect to the annular cavity only in circumferential direction.

A production apparatus for an annular anisotropic bonded magnet, comprising:

• a hollow cylindrical or solid cylindrical core;
• a mainly molding die that surrounds the core to form an annular cavity therebetween;
• and
• an aligning magnetic pole body that includes an even number of permanent magnets arranged uniformly around and in vicinity of outer periphery of the mainly molding die such that directions of magnetic fields thereof are alternately reversed, the permanent magnets being capable of providing an aligning magnetic field to the annular cavity,
• the production apparatus being characterized by further comprising an engaging means that engages a compact into a tubular body while discharging the compact from the annular cavity, the compact being capable of being molded in the annular cavity, the tubular body being provided coaxially with the annular cavity and having an inner peripheral surface capable of being contacted with outer peripheral surface of the compact.

A production apparatus for an annular anisotropic bonded magnet, comprising:

• a mainly molding die that comprises a movable die and a fixed die to form an annular cavity;
• and
• an aligning magnetic pole body that includes an even number of permanent magnets arranged uniformly around and in vicinity of outer periphery of the mainly molding die such that directions of magnetic fields thereof are alternately reversed, the permanent magnets being capable of providing an aligning magnetic field to the annular cavity,
• the production apparatus being characterized by further comprising a driving means that causes the aligning magnetic pole body to relatively move with respect to the annular cavity only in circumferential direction.

A production apparatus for an annular anisotropic bonded magnet, comprising:

• a mainly molding die that comprises a movable die and a fixed die to form an annular cavity;
• and
• an aligning magnetic pole body that includes an even number of permanent magnets arranged uniformly around and in vicinity of outer periphery of the mainly molding die such that directions of magnetic fields thereof are alternately reversed, the permanent magnets being capable of providing an aligning magnetic field to the annular cavity,
• the production apparatus being characterized by further comprising an engaging means that engages a compact into a tubular body while discharging the compact from the annular cavity, the compact being capable of being molded in the annular cavity, the tubular body being provided coaxially with the annular cavity and having an inner peripheral surface capable of being contacted with outer peripheral surface of the compact.