Abstract: The present invention provides a magnetic core which can be produced with improved productivity without increasing a material cost and has required magnetic and mechanical properties and a process for producing the same. The magnetic core is produced by compression molding and thereafter thermally hardening iron-based soft magnetic powder having resin films formed on surfaces of particles thereof. The resin film is an uncured resin film formed by dry mixing the iron-based soft magnetic powder and epoxy resin containing a latent curing agent with each other at a temperature not less than a softening temperature of the epoxy resin and less than a thermal curing starting temperature thereof. The iron-based soft magnetic powder having the resin films formed on the surfaces of the particles thereof is compression molded by using a die to produce a compression molded body.

Abstract: The present invention provides a composite magnetic core, containing magnetic powders poor in its moldability, which can be configured arbitrarily and has a magnetic characteristic excellent in direct current superimposition characteristics and a magnetic element composed of the composite magnetic core and a coil wound around the circumference thereof. A compressed magnetic body (2) obtained by compression-molding magnetic powders is combined with an injection-molded magnetic body (3) obtained by mixing a binding resin with magnetic powders having surfaces thereof electrically insulated and by injection-molding a mixture of the magnetic powders and the binding resin. The compressed magnetic body (2) is press-fitted into the injection-molded magnetic body (3) or bonded thereto at a combining portion thereof to obtain the combined body. The combined body is composed of the injection-molded magnetic body (3) constituting a housing in which the compressed magnetic body (2) is disposed.

Abstract: A magnetic encoder device (3) of the present invention includes a base portion (33) having a mounting surface (33b) for mounting to a rotary shaft (2), a cored bar (35) fitted and fixed over the base portion (33), and a double-row magnetic encoder track (30) formed on the cored bar (35). Through movement of each of magnetic poles of the magnetic encoder track (30) over a region opposed to a magnetic sensor (4), an angle of the rotating rotary shaft is detected. The base portion (33) is formed of a sintered metal, and the mounting surface (33b) is subjected to sizing.

Abstract: The present invention provides a composite magnetic core, containing magnetic powders poor in its moldability, which can be configured arbitrarily and has a magnetic characteristic excellent in direct current superimposition characteristics and a magnetic element composed of the composite magnetic core and a coil wound around the circumference thereof. A compressed magnetic body (2) obtained by compression-molding magnetic powders is combined with an injection-molded magnetic body (3) obtained by mixing a binding resin with magnetic powders having surfaces thereof electrically insulated and by injection-molding a mixture of the magnetic powders and the binding resin. The compressed magnetic body (2) is press-fitted into the injection-molded magnetic body (3) or bonded thereto at a combining portion thereof to obtain the combined body. The combined body is composed of the injection-molded magnetic body (3) constituting a housing in which the compressed magnetic body (2) is disposed.

Abstract: The present invention provides a composite magnetic core, containing magnetic powders poor in its moldability, which can be configured arbitrarily and has a magnetic characteristic excellent in direct current superimposition characteristics and a magnetic element composed of the composite magnetic core and a coil wound around the circumference thereof. A compressed magnetic body (2) obtained by compression-molding magnetic powders is combined with an injection-molded magnetic body (3) obtained by mixing a binding resin with magnetic powders having surfaces thereof electrically insulated and by injection-molding a mixture of the magnetic powders and the binding resin. The compressed magnetic body (2) is press-fitted into the injection-molded magnetic body (3) or bonded thereto at a combining portion thereof to obtain the combined body. The combined body is composed of the injection-molded magnetic body (3) constituting a housing in which the compressed magnetic body (2) is disposed.

Abstract: A magnetic encoder device (3) of the present invention includes a base portion (33) having a mounting surface (33b) for mounting to a rotary shaft (2), a cored bar (35) fitted and fixed over the base portion (33), and a double-row magnetic encoder track (30) formed on the cored bar (35). Through movement of each of magnetic poles of the magnetic encoder track (30) over a region opposed to a magnetic sensor (4), an angle of the rotating rotary shaft is detected. The base portion (33) is formed of a sintered metal, and the mounting surface (33b) is subjected to sizing.

Abstract: The present invention provides a magnetic core which can be produced with improved productivity without increasing a material cost and has required magnetic and mechanical properties and a process for producing the same. The magnetic core is produced by compression molding and thereafter thermally hardening iron-based soft magnetic powder having resin films formed on surfaces of particles thereof. The resin film is an uncured resin film formed by dry mixing the iron-based soft magnetic powder and epoxy resin containing a latent curing agent with each other at a temperature not less than a softening temperature of the epoxy resin and less than a thermal curing starting temperature thereof. The iron-based soft magnetic powder having the resin films formed on the surfaces of the particles thereof is compression molded by using a die to produce a compression molded body.

Abstract: The present invention provides a composite magnetic core, containing magnetic powders poor in its moldability, which can be configured arbitrarily and has a magnetic characteristic excellent in direct current superimposition characteristics and a magnetic element composed of the composite magnetic core and a coil wound around the circumference thereof. A compressed magnetic body (2) obtained by compression-molding magnetic powders is combined with an injection-molded magnetic body (3) obtained by mixing a binding resin with magnetic powders having surfaces thereof electrically insulated and by injection-molding a mixture of the magnetic powders and the binding resin. The compressed magnetic body (2) is press-fitted into the injection-molded magnetic body (3) or bonded thereto at a combining portion thereof to obtain the combined body. The combined body is composed of the injection-molded magnetic body (3) constituting a housing in which the compressed magnetic body (2) is disposed.

Abstract: A method for producing a rare-earth alloy based binderless magnet according to the present invention includes the steps of: (A) providing a rapidly solidified rare-earth alloy magnetic powder; and (B) compressing and compacting the rapidly solidified rare-earth alloy magnetic powder by a cold process without using a resin binder, thereby obtaining a compressed compact, 70 vol % to 95 vol % of which is the rapidly solidified rare-earth alloy magnetic powder.

Abstract: A method for producing a rare-earth alloy based binderless magnet according to the present invention includes the steps of: (A) providing a rapidly solidified rare-earth alloy magnetic powder; and (B) compressing and compacting the rapidly solidified rare-earth alloy magnetic powder by a cold process without using a resin binder, thereby obtaining a compressed compact, 70 vol % to 95 vol % of which is the rapidly solidified rare-earth alloy magnetic powder.

Abstract: A soft magnetic compact which is produced by using soft magnetic composite powder in which the surface of magnetic powder is covered with an electrical insulating material containing at least an inorganic insulating material, and a resin material is fusion-bonded to the surface of the inorganic insulating material so as to partially cover the surface of the soft magnetic powder. Accordingly, it is possible to ensure an electrical insulating property between pieces of soft magnetic material powder to secure a good magnetic characteristics and to easily mold a compact.

Abstract: A soft magnetic compact which is produced by using soft magnetic composite powder in which the surface of magnetic powder is covered with an electrical insulating material containing at least an inorganic insulating material, and a resin material is fusion-bonded to the surface of the inorganic insulating material so as to partially cover the surface of the soft magnetic powder. Accordingly, it is possible to ensure an electrical insulating property between pieces of soft magnetic material powder to secure a good magnetic characteristics and to easily mold a compact.