Chip-type inductor

• US 4,543,553 A
• Filed: 05/16/1984
• Issued: 09/24/1985
• Est. Priority Date: 05/18/1983
• Status: Expired due to Term

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Mandai, Harufumi, Tomono, Kunisaburo
• Primary Examiner(s): Kozma, Thomas J.
• Application Number:
  US06/610,682
• Time in Patent Office: 496 Days
• Field of Search: 336/200, 336/232, 336/192, 336/221, 336/83, 361/412, 361/414, 29/602 R, 29/851, 29/830, 29/853, 29/606
• US Class Current: 336/83
• CPC Class Codes: H01F 17/0013 with stacked layers
• CPC Class Codes: H01F 17/04 with magnetic core
• CPC Class Codes: H01F 41/046 structurally combined with ferromagnetic material
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor

Abstract

A present invention is a chip-type inductor comprising a laminated structure (28) of a plurality of magnetic layers (1 to 8) in which linear conductive patterns (9 to 21) extending between the respective magnetic layers are connected successively in a form similar to a coil so as to produce an inductance component. The conductive patterns (12, 14, 16, 18, 20, 11 and 10) formed on the upper surfaces of the magnetic layers and the conductive patterns (9, 13, 15, 17, 19 and 21) formed on the lower surfaces of the magnetic layers are connected with each other in the interfaces of the magnetic layers and are also connected each other via through-holes (22 to 27) formed in the magnetic layers, so that the conductive patterns are continuously connected in a form similar to a coil.

Claims

1. A chip-type inductor comprising a laminated structure of n magnetic layers, n being a natural number greater than or equal to 4, where linear conductive patterns extending between the magnetic layers are connected successively in a form similar to a coil so as to produce an inductance component, characterized in that:

of the n magnetic layers, the uppermost first magnetic layer is provided with a conductive pattern formed on the lower surface thereof and the lowermost nth magnetic layer and the adjacent n-1th magnetic layer are provided with respective conductive patterns on the upper surfaces thereof;

each of the second to the n-2th magnetic layers is provided with a respective pair of conductive patterns, one of the pair being located on the upper surface thereof, the other of the pair being located on the lower surface thereof, each of said second to n=2th magnetic layers insulating its respective pair of conductive patterns from one another;

the conductive pattern formed on the lower surface of the first to the n-2th magnetic layers being in direct contact with the conductive pattern formed on the upper surface of the second to n-1th magnetic layers, respectively;

in each of the second to the n-1th magnetic layers, a respective, electrically non-conductive, through-hole is formed in a region where no conductive pattern is formed in the layer;

the conductive pattern formed on the upper surface of the third through nth magnetic layer being connected to the conductive pattern formed on the lower surface of the first through n-2th magnetic layers, respectively, via the through-hole formed in the second through n-1th magnetic layers, respectively; and

lead out electrodes are connected to the conductive layers formed on the first and nth electrodes, respectively.

2. A chip-type inductor in accordance with claim 1, wherein each of said magnetic layers is planar and is rectangular in shape as viewed in its plane such that each of the major surfaces of each magnetic layer has first and second short sides and first and second long sides, and wherein the conductive pattern formed on the upper surface of the second through n-1th magnetic layers is formed along the first long side and the first short side of the respective magnetic layer on which it is formed and the conductive pattern formed on the lower surface of the first through n-2th magnetic layers is formed along the second long side and the first short side of the respective magnetic layer in which it is formed, the through-hole formed in the second through n-1th magnetic layers being located in a position along the second short side of the respective magnetic layer in which it is formed.

3. A chip-type inductor in accordance with claim 1, wherein each of said through-holes is circular in shape.

4. A chip-type inductor in accordance with claim 1, wherein each of said through-holes is oval in shape.

5. A chip-type inductor in accordance with claim 1, wherein each of said second through n-1th magnetic layers also has a second through-hole formed therein the two through-holes formed in each respective magnetic layer being located adjacent one another.

6. A chip-type inductor, comprising:

n generally planar magnetic layers, n being a natural number greater than or equal to 4, said magnetic layers being stacked one atop the other to form a stack of magnetic layers;

a conductive pattern formed on the lower surface of the uppermost first magnetic layer and a respective conductive pattern formed on the upper surfaces of the lowermost nth magnetic layer and the adjacent n-1th magnetic layer, respectively;

a respective conductive pattern being formed on the upper surface of the second to n-2th magnetic layers and a respective conductive pattern being formed on the lower surface of each of the second to n-2th magnetic layers, the second to n-2th layers insulating its respective conductive pattern on the upper surface thereof from its respective conductive pattern on the lower surface thereof, the conductive pattern formed on the lower surface of the first to n-2th magnetic layers being in direct contact with the conductive pattern formed on the upper surface of the second to n-1th magnetic layers, respectively;

a respective, electrically non-conductive, through-hole formed in each of said second to n-1th magnetic layers in a region where no conductive pattern is formed in the layer in which the through-hole is formed, the relative locations of said conductive patterns formed on said first to nth conductive layers and the relative locations of said through-holes being such that after said magnetic layers are compressed together by a force extending in a direction generally perpendicular to the plane of said magnetic layers, the conductive pattern formed on the upper surface of the third through nth magnetic layer comes into physical contact with the conductive pattern formed on the lower surface of the first through n-2th magnetic layers, respectively, via the through-hole formed in the second through n-1th magnetic layers, respectively, said conductive patterns being so connected to define a continuous conductor in a form similar to a coil so as to produce an inductance component; and

lead out electrodes connected to the conductive layers formed on the first and nth electrodes, respectively.

7. A chip-type inductor in accordance with claim 6, wherein each of said magnetic layers is rectangular in shape as viewed in its plane such that each of the major surfaces of the magnetic layer has first and second short sides and first and second long sides, and wherein the conductive pattern formed on the upper surface of the second through nth magnetic layers is formed along the first long side and the first short side of the respective magnetic layer on which it is formed and the conductive pattern formed on the lower surface of the first through n-2th magnetic layers is formed along the second long side and the first short side of the respective magnetic layer on which it is formed, the through-hole formed in the second through n-1th magnetic layers being located in a position along the second short side of the respective magnetic layer in which it is formed.

8. A chip-type inductor in accordance with claim 6, wherein each of said through-holes is circular in shape.

9. A chip-type inductor in accordance with claim 6, wherein each of said through-holes is oval in shape.

10. A chip-type inductor in accordance with claim 6, wherein each of said second through n-1th magnetic layers also has a second through-hole formed therein, the two through-holes formed in each respective magnetic layer being located adjacent one another.