Method for manufacturing electronic component with coil

• US 9,087,634 B2
• Filed: 03/14/2013
• Issued: 07/21/2015
• Est. Priority Date: 03/14/2013
• Status: Active Grant

• Current Assignee: Sumida Corporation
• Original Assignee: Sumida Corporation
• Inventors: Sakamoto, Shinichi, Malcolm, Douglas James
• Primary Examiner(s): Kim, Paul D
• Application Number:
  US13/804,857
• Publication Number:
  US 20140259640A1
• Time in Patent Office: 859 Days
• Field of Search: 296/021, 29605-607, 298/29, 298/32, 298/41, 29855-858, 298/83, 298/84, 336/178, 336/200, 336/212, 336/223, 336/232, 100/214, 264/272.11, 425/398, 425/412, 425/470, 83/29, 83/35, 83/36, 83/50
• US Class Current: 1/1
• CPC Class Codes: H01F 17/04 with magnetic core
• CPC Class Codes: H01F 2017/048 with encapsulating core, e.g. made of resin and magnetic powder
• CPC Class Codes: H01F 27/022 Encapsulation
• CPC Class Codes: H01F 27/24 Magnetic cores
• CPC Class Codes: H01F 27/255 made from particles H01F27/26 takes precedence
• CPC Class Codes: H01F 27/2828 Construction of conductive connections, of leads
• CPC Class Codes: H01F 27/29 Terminals; Tapping arrangements for signal inductances
• CPC Class Codes: H01F 41/02 for manufacturing cores, coils, or magnets H01F41/14 takes precedence; for dynamo-electric machines H02K15/00
• 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: H01F 41/064 Winding non-flat conductive wires, e.g. rods, cables or cords
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor
• CPC Class Codes: Y10T 29/49071 by winding or coiling

Abstract

A method for manufacturing an electronic component for avoiding electromagnetic interference includes: (a) placing a T-shaped core and an air-core coil in a metal mold; (b) injecting a mixture of a composite magnetic material and a resin into the metal mold so that the T-shaped core and the air-core coil are embedded by the mixture; (c) heating the mixture at a first temperature; (d) adjusting an outer shape while removing excessive mixture; and (e) hardening the mixture. The method may further include a process of polishing an outside of the hardened mixture. The method may further include a process of applying a pressure of 0.1 to 20.0 kg/cm² to the mixture for adjusting an outer shape of the mixture by a movable punch of a press machine before the hardening process.

Claims

1. A method for manufacturing an electronic component comprising:

placing a T-shaped core and an air-core coil in a mold;

injecting a mixture of a composite magnetic material and a resin into the mold so that the T-shaped core and the air-core coil are embedded by the mixture;

heating the mixture at a first temperature;

after the heating the mixture at the first temperature, pressing and flattening a to surface of the mixture in the mold while removing excessive mixture; and

after the pressing and flattening the to surface of the mixture, hardening the mixture at a second temperature that is higher than the first temperature.

2. The method for manufacturing an electronic component according to claim 1, wherein

the first temperature is in a range of 60 to 100°

C., and

the heating is performed for 5 to 120 minutes.

3. The method for manufacturing an electronic component according to claim 1, wherein

the hardening is performed by heating the mixture at the second temperature in a range of 120 to 200°

C. for 10 to 90 minutes.

4. The method for manufacturing an electronic component according to claim 1 further comprising:

winding a round wire to form the air-core coil; and

flattening both ends of the wire.

5. The method for manufacturing an electronic component according to claim 1 further comprising:

winding a flat rectangular wire to form the air-core coil, wherein

an inside diameter of the air-core coil is larger than an outside diameter of a core part of the T-shaped core.

6. The method for manufacturing an electronic component according to claim 1 further comprising:

applying solder at both ends of end wires of the air-core coil;

placing the air-core coil on a first surface of the T shaped core;

bending the end wires at a side of the T-shaped core; and

fixing both ends to a second surface of the T-shaped core opposite the first surface.

7. The method for manufacturing an electronic component according to claim 1 further comprising:

applying a pressure of 0.1 to 20.0 kg/cm² to the mixture in the pressing and flattening the to surface of the mixture by a movable punch of a press machine before the hardening.

8. The method for manufacturing an electronic component according to claim 1, wherein

the injecting is performed by a dispenser that includes:

a discharge opening that discharges the mixture;

a material tank that stores the mixture;

a flow passage in which the mixture flows;

a valve that is provided in the flow passage and controls a flow of the mixture;

a valve driving unit that opens and closes the valve; and

a mixer that is provided at a trailing end of the flow passage and that mixes the mixture, and that supplies the mixture toward the discharge opening.

9. The method for manufacturing an electronic component according to claim 1, wherein

the pressing and flattening is performed by a sharp edge of a remover before the heating is performed.

10. The method for manufacturing an electronic component according to claim 9 further comprising:

applying a pressure of 0.1 to 20.0 kg/cm² to the mixture in the pressing and flattening the to surface of the mixture by a movable punch of a press machine before the hardening.

11. The method for manufacturing an electronic component according to claim 9 wherein

the sharp edge of the remover slides along the top surface of the mixture at an angle of 0 to 80 degrees with respect to a surface of the mold and a pressure of 0.1 to 20.0 kg/cm² is applied to the mixture.

12. A method for manufacturing an electronic component comprising:

placing an air-core coil wrapped core in a mold;

embedding the air-core wrapped core in a mixture of a composite magnetic material and a resin in the mold;

heating the mixture at a first temperature;

after the heating the mixture at the first temperature, pressing and flattening a to surface of the mixture in the mold while removing excessive mixture; and

after the pressing and flattening the to surface of the mixture, hardening the mixture at a second temperature that is higher than the first temperature.

13. The method for manufacturing an electronic component according to claim 12, wherein

the first temperature is in a range of 60 to 100°

C., and

the heating is performed for 5 to 120 minutes.

14. The method for manufacturing an electronic component according to claim 13, wherein

the hardening is performed by heating the mixture at the second temperature in a range of 120 to 200°

C. for 10 to 90 minutes.

15. The method for manufacturing an electronic component according to claim 12 further comprising:

applying a pressure of 0.1 to 20.0 kg/cm² to the mixture in the pressing and flattening the to surface of the mixture before the hardening.

16. The method for manufacturing an electronic component according to claim 12 further comprising:

polished an outside of the hardened mixture.

17. The method for manufacturing an electronic component according to claim 16, wherein

in the pressing and flattening, a remover slides along the top surface of the mixture at an angle of 0 to 80 degrees with respect to a surface of the mold and a pressure of 0.1 to 20.0 kg/cm² is applied to the mixture.

18. A method for manufacturing an electronic component comprising:

manufacturing a T-shaped core and an air-core coil separately;

assembling the air-core coil with the T-shaped core;

placing the T-shaped core and the air-core coil in a mold; and

injecting a mixture of a composite magnetic material and a resin into the mold so that the T-shaped core and the air-core coil are embedded by the mixture, wherein

the assembling the air-core coil with the T-shaped core includes;

placing the air-core coil on a first surface of the T-shaped core;

bending end wires of the air-core coil at a side of the T-shaped core; and

fixing both ends of the end wires to a second surface, which is opposite to the first surface, of the T-shaped core.

19. The method for manufacturing an electronic component according to claim 18, wherein

the assembling the air-core coil with the T-shaped core includes:

applying solder at the both ends of the end wires of the air-core coil.

20. The method for manufacturing an electronic component according to claim 18 further comprising:

winding a round wire to form the air-core coil; and

flattening the both ends of the round wire.

21. The method for manufacturing an electronic component according to claim 18 further comprising:

winding a flat rectangular wire to form the air-core coil, wherein

an inside diameter of the air-core coil is larger than an outside diameter of a core part of the T-shaped core.

22. A method for manufacturing an electronic component comprising:

manufacturing a T-shaped core and an air-core coil separately;

assembling the air-core coil with the T-shaped core;

placing the T-shaped core and the air-core coil in a mold; and

injecting a mixture of a composite magnetic material and a resin into the mold so that the T-shaped core and the air-core coil are embedded by the mixture, wherein

the assembling the air-core coil with the T-shaped core includes;

placing the air-core coil on a first surface of the T-shaped core;

bending end wires of the air-core coil at a first side of the T-shaped core;

extending the end wires of the air-core coil through a second surface, which is opposite to the first surface, of the T-shaped core; and

bending the end wires at a second side, which is opposite to the first side, of the T-shaped core.

23. The method for manufacturing an electronic component according to claim 22, wherein

the assembling the air-core coil with the T-shaped core includes:

applying solder at both ends of the end wires of the air-core coil.

24. The method for manufacturing an electronic component according to claim 22 further comprising:

winding a flat rectangular wire to form the air-core coil, wherein

an inside diameter of the air-core coil is larger than an outside diameter of a core part of the T-shaped core.

25. The method for manufacturing an electronic component according to claim 22 further comprising:

heating the mixture at a first temperature after injecting the mixture into the mold;

after heating the mixture at the first temperature, pressing and flattening a top surface of the mixture in the mold while removing excessive mixture; and

after the pressing and flattening the top surface of the mixture, hardening the mixture at a second temperature that is higher than the first temperature.

26. The method for manufacturing an electronic component according to claim 25, wherein

the first temperature is in a range of 60 to 100°

C., and

the heating is performed for 5 to 120 minutes.

27. The method for manufacturing an electronic component according to claim 25, wherein

the hardening is performed by heating the mixture at the second temperature in a range of 120 to 200°

C. for 10 to 90 minutes.

28. The method for manufacturing an electronic component according to claim 25 further comprising:

applying a pressure of 0.1 to 20.0 kg/cm2 to the mixture in the pressing and flattening the top surface of the mixture by a movable punch of a press machine before the hardening.