Coil component including magnetic body

• US 8,922,325 B2
• Filed: 09/02/2010
• Issued: 12/30/2014
• Est. Priority Date: 09/03/2009
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Shibuya, Tomonori, Imanishi, Tsunetsugu
• Primary Examiner(s): Lian, Mangtin
• Application Number:
  US13/391,911
• Publication Number:
  US 20120146759A1
• Time in Patent Office: 1,580 Days
• Field of Search: 336/221, 336/233, 336/212, 336/214, 336/184, 336/215
• US Class Current: 336/233
• CPC Class Codes: H01F 17/043 with two, usually identical or nearly identical parts enclosing completely the coil (pot cores)
• CPC Class Codes: H01F 27/255 made from particles H01F27/26 takes precedence
• 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

Abstract

A coil component comprising a first split magnetic core and a second split magnetic core, each having an outer core leg, an inner core leg and a back yoke connecting the outer core leg and the inner core leg, and a coil block mounted to the inner core leg, wherein the outer core leg has a sectional area smaller than a sectional area of the inner core leg, a density of magnetic body in the outer core leg is different from a density of the magnetic body in any of the inner core leg and the back yoke, and the first split magnetic core and the second split magnetic core are butted against each other to form a magnetic core of a closed magnetic circuit.

Claims

1. A coil component comprising:

a magnetic core having an outer core leg, an inner core leg and a back yoke connecting the outer core leg and the inner core leg,

each of the outer core leg, the inner core leg and the back yoke including a magnetic body formed of magnetic powder; and

a coil block mounted to the inner core leg,

wherein;

the inner core leg includes an interior area in which resin is not fully impregnated,

a density of the magnetic metal powder in the outer core leg is different from both of a density of the magnetic metal powder in the inner core leg and a density of the magnetic metal powder in the back yoke, and

the inner core leg is formed in a substantially uniform distribution of the density.

2. The coil component of claim 1,

wherein the magnetic core having a first split magnetic core and a second split magnetic core, and the outer core leg, the inner core leg and the back yoke are included in the first split magnetic core, and the second split magnetic core is formed in a rod-like shape of a plate-like shape, and the first split magnetic core and the second split magnetic core are butted against each other to form the magnetic core of a closed magnetic circuit.

3. The coil component of claim 1, wherein the density of the magnetic metal powder in the back yoke is formed substantially equal to the density of the magnetic metal powder in the inner core leg, and the magnetic body in the back yoke is formed uniform in distribution of the density.

4. The coil component of claim 1, wherein the density of the magnetic metal powder in the back yoke is formed higher than the density of the magnetic metal powder in the inner core leg, and the magnetic body in the back yoke is formed uniform in distribution of the density.

5. The coil component of claim 1, wherein a dimension of a smallest width portion in sectional area of the outer core leg is smaller than a dimension of a smallest width portion in sectional area of the inner core leg.

6. The coil component of claim 1, wherein the magnetic body contains a resin.

7. The coil component of claim 1, wherein the first split magnetic core and the second split magnetic core are formed by impregnating the magnetic body.

8. The coil component of claim 2, wherein the density of the magnetic metal powder in the back yoke is formed substantially equal to the density of the magnetic metal powder in the inner core leg, and the magnetic body in the back yoke is formed uniform in distribution of the density.

9. The coil component of claim 2, wherein the density of the magnetic metal powder in the back yoke is formed higher than the density of the magnetic metal powder in the inner core leg, and the magnetic body in the back yoke is formed uniform in distribution of the density.

10. The coil component of claim 2, wherein a dimension of a smallest width portion in sectional area of the outer core leg is smaller than a dimension of a smallest width portion in sectional area of the inner core leg.

11. The coil component of claim 2, wherein the magnetic body contains a resin.

12. The coil component of claim 2, wherein the first split magnetic core and the second split magnetic core are formed by impregnating the magnetic body.

13. The coil component of claim 1,

wherein the outer core leg is formed in substantially uniform distribution of the density.

14. The coil component of claim 1,

wherein the magnetic core having a first split magnetic core and a second split magnetic core, and the outer core leg, the inner core leg and the back yoke are included in each of the first split magnetic core and the second split magnetic core, and the first split magnetic core and the second split magnetic core are butted against each other to form the magnetic core of a closed magnetic circuit.

15. The coil component of claim 1,

wherein the inner core leg has two end portions which are disposed equidistant from a center of the coil component, and the inner core leg is formed in a substantially uniform distribution of the density between the two end portions.

16. The coil component of claim 1, wherein the magnetic metal powder in the outer core leg, the magnetic metal powder in the outer core leg and the magnetic metal powder in the back yoke are a same magnetic metal powder.