Chip-type common mode choke coil

• US 6,522,230 B2
• Filed: 07/16/2001
• Issued: 02/18/2003
• Est. Priority Date: 07/17/2000
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Kasahara, Kazuo, Hanato, Yoshio
• Primary Examiner(s): Mai, Anh
• Application Number:
  US09/906,250
• Publication Number:
  US 20020057160A1
• Time in Patent Office: 582 Days
• Field of Search: 336/200, 336/223, 336/232, 336/83, 336/192, 336/198, 336/208
• US Class Current: 336/83
• CPC Class Codes: H01F 17/045 with core of cylindric geometry and coil wound along its longitudinal axis, i.e. rod or drum core
• CPC Class Codes: H01F 2017/0093 Common mode choke coil
• 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

Abstract

A chip-type common mode choke coil having protrusions extending in an axial direction of a winding core portion and being formed in areas between a plurality of electrodes (four electrodes), at the inside surfaces of two flanges, that is, at opposing surfaces of the two flanges, one being disposed on each end of the winding core portion, in order to increase the stroke distances between the corresponding electrodes. In the choke coil, the protrusions separate the corresponding electrodes in order to prevent the occurrence of a short circuit caused by two wires also coming into contact with the electrodes adjacent to the electrodes to which they are primarily to be connected. For the protrusions, protrusions having at least one of a triangular shape, a square shape, a rectangular shape, a trapezoidal shape, and a substantially semicircular shape in plan view are disposed. Accordingly, the chip-type common mode choke coil makes it possible to prevent the occurrence of a short circuit caused by the wires coming into contact with the corresponding adjacent electrodes, the occurrence of reduced withstand pressure, and the occurrence of insufficient insulation. In addition, it can have high mechanical strength as a result of increased cross-sectional areas of the legs, and be highly reliable.

Claims

1. A chip-type common mode choke coil comprising:

a winding core portion;

flanges disposed on both ends of the winding core portion, respectively;

a plurality of electrodes disposed on each of the flanges at a predetermined distance from each other so as not to come into electrical conduction with each other; and

a plurality of wires wound upon the winding core portion, beginning ends and termination ends of the wires being connected to predetermined ones of the plurality of electrodes;

wherein

protrusions which protrude in an axial direction of the winding core portion are provided in areas between the respective electrodes, at inside surfaces of the respective flanges disposed on both ends of the winding core portion.

2. A chip-type common mode choke coil according to claim 1, wherein the shape in plan view of the protrusion provided on each flange is at least one of a substantially triangular shape, a substantially rectangular shape, a substantially square shape, a substantially trapezoidal shape, and a substantially semicircular shape.

3. A chip-type common mode choke coil according to claim 1, wherein the chip-type common mode choke coil is a two-circuit, four terminal, chip-type common mode choke coil.

4. A chip-type common mode choke coil according to claim 1, wherein the chip-type common mode choke coil is a a three-circuit, six-terminal, chip-type common mode choke coil.

5. A chip-type common mode choke coil according to claim 1, wherein the core is made of ferrite.

6. A chip-type common mode choke coil according to claim 1, wherein the protrusions have substantially trapezoidal shapes.

7. A chip-type common mode choke coil according to claim 1, wherein the protrusions have substantially semicircular shapes.

8. A chip-type common mode choke coil according to claim 1, wherein the protrusions have substantially triangular shapes.

9. A chip-type common mode choke coil according to claim 1, wherein the protrusions have substantially rectangular shapes.

10. A chip-type common mode choke coil according to claim 1, wherein the wires extend along the protrusions in a relatively gradually bent state.

11. A chip-type common mode choke coil comprising:

a winding core portion;

a plurality of flanges disposed on respective ends of the winding core portion;

a plurality of electrodes disposed on each of the flanges and arranged so as not to come into electrical conduction with each other;

a plurality of wires wound upon the winding core portion and having first and second ends being electrically connected to a respective one of the plurality of electrodes; and

a plurality of protrusions provided in areas between the respective electrodes, at inside surfaces of the respective flanges disposed on both ends of the winding core portion.

12. A chip-type common mode choke coil according to claim 11, wherein the shape in plan view of the protrusion provided on each flange is at least one of a substantially triangular shape, a substantially rectangular shape, a substantially square shape, a substantially trapezoidal shape, and a substantially semicircular shape.

13. A chip-type common mode choke coil according to claim 11, wherein the chip-type common mode choke coil is a two-circuit, four terminal, chip-type common mode choke coil.

14. A chip-type common mode choke coil according to claim 11, wherein the chip-type common mode choke coil is a a three-circuit, six-terminal, chip-type common mode choke coil.

15. A chip-type common mode choke coil according to claim 11, wherein the core is made of ferrite.

16. A chip-type common mode choke coil according to claim 11, wherein the protrusions have substantially trapezoidal shapes.

17. A chip-type common mode choke coil according to claim 11, wherein the protrusions have substantially semicircular shapes.

18. A chip-type common mode choke coil according to claim 11, wherein the protrusions have substantially triangular shapes.

19. A chip-type common mode choke coil according to claim 11, wherein the protrusions have substantially rectangular shapes.

20. A chip-type common mode choke coil according to claim 11, wherein the wires extend along the protrusions in a relatively gradually bent state.