Magnetic element

Patent metadata

Field	Value
Publication number	US-10074471-B2
Application number	US-201515128893-A
Country	US
Kind code	B2
Filing date	Mar 18, 2015
Priority date	Mar 24, 2014
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

The present invention provides a magnetic element in which iron loss-caused heat generation is restrained and which can be produced with a high productivity. The magnetic element has a magnetic body which allows a magnetic flux generated by a coil ( 4 ) to pass therethrough. The magnetic body is a combined body formed by combining two halves, of the magnetic body composed of the compression molded and injection molded bodies, obtained by bisection made in an axial direction of the coil with each other. A compression molded magnetic body ( 2 ) is disposed at a portion generating iron loss-caused heat to a high extent or a portion inferior in heat dissipation performance. An injection molded magnetic body ( 3 ) is disposed at a portion other than the portion where the compression molded magnetic body is disposed. The compression molded and injection molded magnetic bodies are combined with each other.

First claim

The invention claimed is:

1. A magnetic element comprising a coil; and a magnetic body which allows a magnetic flux generated by said coil to pass therethrough, said coil being disposed inside said magnetic body and enclosed in said magnetic body,
wherein said magnetic element is pot-shaped,
wherein in said magnetic body, a compression molded magnetic body is disposed at a portion that generates iron loss-caused heat to a high extent or a portion inferior in heat dissipation performance; and an injection molded magnetic body is disposed at a portion other than said portion where said compression molded magnetic body is disposed; and said compression molded magnetic body and said injection molded magnetic body are combined with each other, and
wherein said compression molded magnetic body is columnar; said compression molded magnetic body is disposed at an inside diameter side of said coil; said injection molded magnetic body is disposed at an outside diameter side of said coil; said coil is formed by winding a winding onto said compression molded magnetic body; an entire periphery of said coil except a side thereof facing said compression molded magnetic body is completely covered by said injection molded magnetic body; and both end surfaces of a column which is said compression molded magnetic body are exposed to a surface of said magnetic body composed of said compression molded and injection molded bodies.

2. A magnetic element according to claim 1 , wherein of said compression molded and injection molded magnetic bodies, at least said injection molded magnetic body is a combined body formed by combining two halves, of said injection molded magnetic body, obtained by bisection made in an axial direction of said coil with each other.

3. A magnetic element according to claim 1 , wherein said compression molded magnetic body has a void portion inside said magnetic body composed of said compression molded and injection molded bodies.

4. A magnetic element according to claim 1 , wherein another compression molded magnetic body is formed on a periphery of an end surface of said compression molded magnetic body which is exposed to a surface of said magnetic element so as to be exposed to a surface of said magnetic element.

5. A magnetic element according to claim 1 , wherein said compression molded magnetic body is formed from amorphous metal powder and said injection molded magnetic body is formed from amorphous metal powder and thermoplastic resin.

Assignees

• Ntn Toyo Bearing Co Ltd

Inventors

• Sakai Kayo
• Shimazu Eiichirou
• Miyazaki Shinji
• Oda Takayuki

Classifications

• H01F2003/106

  Magnetic circuits using combinations of different magnetic materials · CPC title

• H01F17/043

  with two, usually identical or nearly identical parts enclosing completely the coil (pot cores) · CPC title

• H01F27/255 Primary

  made from particles (H01F27/26 takes precedence) · CPC title

• H01F3/10

  Composite arrangements of magnetic circuits · CPC title

• H01F37/00

  Fixed inductances not covered by group H01F17/00 · CPC title