Composite magnetic body, and magnetic element and method of manufacturing the same

• US 20040209120A1
• Filed: 05/11/2004
• Published: 10/21/2004
• Est. Priority Date: 04/28/2000
• Status: Active Grant

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Fujii, Hiroshi, Kato, Junichi, Takahashi, Takeshi, Inoue, Osamu, Matsutani, Nobuya
• Granted Patent: US 6,888,435 B2
• Time in Patent Office: Days
• US Class Current: 428/694B
• CPC Class Codes: H01F 1/24 the particles being insulated
• CPC Class Codes: H01F 1/26 by macromolecular organic substances
• CPC Class Codes: H01F 1/28 dispersed or suspended in a bonding agent
• CPC Class Codes: H01F 17/04 with magnetic core
• CPC Class Codes: H01F 27/027 specially adapted for combination of signal type inductors or transformers with electronic circuits, e.g. mounting on printed circuit boards
• CPC Class Codes: H01F 27/292 Surface mounted devices
• CPC Class Codes: H01F 41/0246 Manufacturing of magnetic circuits by moulding or by pressing powder magnetic cores made by moulding or by pressing powder H01F27/255; soft magnetic particles H01F1/20, H01F1/36
• CPC Class Codes: H01F 41/127 Encapsulating or impregnating encapsulating coil and core H01F41/005
• CPC Class Codes: Y10S 156/922 Specified electronic component delaminating in preparation for recycling
• CPC Class Codes: Y10T 156/1082 Partial cutting bonded sandwich [e.g., grooving or incising]
• CPC Class Codes: Y10T 156/11 Methods of delaminating, per se; i.e. , separating at bonding face
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor
• CPC Class Codes: Y10T 29/49021 Magnetic recording reproducing transducer [e.g., tape head, core, etc.]
• CPC Class Codes: Y10T 29/49071 by winding or coiling
• CPC Class Codes: Y10T 29/49073 by assembling coil and core
• CPC Class Codes: Y10T 29/49158 with molding of insulated base
• CPC Class Codes: Y10T 29/49172 by molding of insulating material
• CPC Class Codes: Y10T 29/49176 with molding of electrically insulating material
• CPC Class Codes: Y10T 29/4922 with molding of insulation
• CPC Class Codes: Y10T 29/49261 : by composite casting or molding
• CPC Class Codes: Y10T 29/49277 : including casting or molding
• CPC Class Codes: Y10T 428/11 : Magnetic recording head
• CPC Class Codes: Y10T 428/32 : Composite [nonstructural laminate] of inorganic material having metal-compound-containing layer and having defined magnetic layer

Abstract

The present invention provides a composite magnetic body containing metallic magnetic powder and thermosetting resin and having a packing ratio of the metallic magnetic powder of 65 vol % to 90 vol % and an electrical resistivity of at least 10⁴ Ω·cm. When a coil is embedded in this composite magnetic body, a miniature magnetic element can be obtained that has a high inductance value and is excellent in DC bias characteristics.

Claims

1-16. -16. (canceled)

17. A magnetic element comprising:

a composite magnetic body comprising metallic magnetic powder and thermosetting resin and having a packing ratio of the metallic magnetic powder of 65 vol % to 90 vol % and an electrical resistively of at least 10⁴ Ω

·

cm; and

a coil embedded in the composite magnetic body,

further comprising a second magnetic body when the composite magnetic body is defined as a first magnetic body,

wherein the second magnetic body has a higher magnetic permeability than that of the first magnetic body.

18. The magnetic element according to claim 17, wherein the coil and the second magnetic body are disposed so that a closed path passing through inner and outer sides of the coil via the second magnetic body alone is not formed.

19. The magnetic element according to claim 17, wherein the second magnetic body is at least one selected from ferrite and a dust core.

20-24. -24. (canceled)