Common mode choke coil and method of manufacturing the same

• US 20030163914A1
• Filed: 04/03/2003
• Published: 09/04/2003
• Est. Priority Date: 03/30/1999
• Status: Active Grant

• Current Assignee: Taiyo Yuden Company Limited (Taiyo Yuden Co)
• Original Assignee: Fujitsu Limited
• Inventors: Takayama, Manabu, Kumahora, Tetsuo, Taketomi, Kouji
• Granted Patent: US 6,938,327 B2
• Time in Patent Office: Days
• US Class Current: 29/605
• CPC Class Codes: H01F 17/06 with core substantially closed in itself, e.g. toroid
• CPC Class Codes: H01F 27/323 Insulation between winding turns, between winding layers
• CPC Class Codes: H01F 37/00 Fixed inductances not covered by group H01F17/00
• 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: Y10T 29/4902 Electromagnet, transformer or inductor
• 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 29/49076 From comminuted material

Abstract

A common mode choke coil has a plurality of metallic conducting wires buried into a sintered magnetic material such that the metallic conducting wires are proximate to each other and an electrode mounted on a surface of the sintered magnetic material so as to be connected to each end portion of each of the metallic conducting wires. The metallic conducting wires are integrally coated with a non-magnetic and electrically insulating material at a predetermined distance between each of the metallic conducting wires to thereby form coated conducting wires. The coated conducting wires buried into the sintered magnetic material are thus obtained.

Claims

1. A method of manufacturing a common mode choke coil comprising the steps of:

a) kneading powder of a magnetic material and a binder together;

b) burying coated conducting wires into a semimanufactured product obtained in step a), said coated conducting wires each having a length equivalent to at least several common mode choke coils and being integrally coated with a nonmagnetic and electrically insulating material in a state in which a plurality of metallic conducting wires are spaced apart with a predetermined distance therebetween;

wherein step b) further comprises the steps of;

b1) forming a core of the semimanufactured product obtained in step a)

b2) winding said coated conducting wires around said core; and

thereafter,

b3) coating the semimanufactured product obtained in step b2) with the semimanufactured product obtained in step a);

c) dividing the semimanufactured product obtained in step b) into pieces, each piece having a length equivalent to one common mode choke coil;

d) exposing both end portions of each of said metallic conducting wires which constitute said coated conducting wires;

e) sintering the semimanufactured product obtained in step d); and

thereafter,

f) connecting an electrode to each of said end portions of each of said metallic conducting wires;

wherein said coated conducting wires are twisted together.

2. A method of manufacturing a common mode choke coil comprising the steps of:

a) kneading powder of a magnetic material and a binder together;

b) burying coated conducting wires into a semimanufactured product obtained in step a), said coated conducting wires each having a length equivalent to at least several common mode choke coils and being integrally coated with a nonmagnetic and electrically insulating material in a state in which a plurality of metallic conducting wires are spaced apart with a predetermined distance therebetween;

c) dividing the semimanufactured product obtained in step b) into pieces, each piece having a length equivalent to one common mode choke coil;

d) exposing both end portions of each of said metallic conducting wires which constitute said coated conducting wire;

e) connecting an electrode to each of said end portions of each of said metallic conducting wires; and

thereafter

f) sintering the semimanufactured product obtained in step e).

3. A method of manufacturing a common mode choke coil according to claim 2, wherein said step b) further comprises the steps of:

b1) forming a core of the semimanufactured product obtained in step a);

b2) winding said coated conducting wires around said core; and

thereafter

b3) coating the semimanufactured product obtained in step b2) with the semimanufactured product obtained in step a).

4. A method of manufacturing a common mode choke coil according to claim 3, wherein said coated conducting wires are twisted together.

5. A method of manufacturing a common mode choke coil comprising the steps of:

a) kneading powder of a magnetic material and a binder together;

b) burying a coated conducting wire into a semimanufactured product obtained in step a), said coated conducting wires each having a length equivalent to at least several common mode choke coils and being integrally coated with a nonmagnetic and electrically insulating material in a state in which a plurality of metallic conducting wires are spaced apart with a predetermined distance therebetween;

c) sintering the semimanufactured product obtained in step b);

d) dividing the semimanufactured product obtained in step c) into pieces, each piece having a length equivalent to one common mode choke coil;

e) exposing both end portions of each of said metallic conducting wires which constitute said coated conducting wires; and

thereafter

f) connecting an electrode to each of said end portions of each of said metallic conducting wires.

6. A method of manufacturing a common mode choke coil according to claim 5, wherein said step b) further comprises the steps of:

b1) forming a core of the semimanufactured product obtained in step a);

b2) winding said coated conducting wires around said core; and

thereafter

b3) coating the semimanufactured product obtained in step b2) with the semimanufactured product obtained in step a).

7. A method of manufacturing a common mode choke coil according to claim 6, wherein said coated conducting wires are twisted together.