Coil component with covering resin having multiple kinds of metal powders

• US 10,210,974 B2
• Filed: 11/25/2015
• Issued: 02/19/2019
• Est. Priority Date: 11/28/2014
• Status: Active Grant

• Current Assignee: TDK Corporation
• Original Assignee: TDK Corporation
• Inventors: Ohkubo, Hitoshi, Arata, Masazumi, Ohta, Manabu, Kawadahara, Shou, Maeda, Yoshihiro, Kawahara, Takahiro, Eda, Hokuto, Sato, Shigeki
• Primary Examiner(s): Enad, Elvin G
• Assistant Examiner(s): Barnes, Malcolm
• Application Number:
  US14/952,028
• Publication Number:
  US 20160155550A1
• Time in Patent Office: 1,182 Days
• CPC Class Codes: H01F 1/24 the particles being insulated
• CPC Class Codes: H01F 17/0013 with stacked layers
• 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 27/292 Surface mounted devices

Abstract

In a coil component (planar coil element), at least part of a third metal magnetic powder constituting a metal magnetic powder and having a minimum average grain diameter is uncoated, which suppresses a reduction in magnetic permeability. On the other hand, the remaining metal powders are coated with glass, which improves the insulating properties of a metal magnetic powder-containing resin and reduces core loss.

Claims

1. A coil component comprising:

a coil unit including a substrate and a conductor pattern for planar coil provided on the substrate; and

a metal magnetic powder-containing resin covering the coil unit,

wherein;

the metal magnetic powder-containing resin contains three or more kinds of metal powders different in average grain diameter,

the metal powders are made of pure metal or alloy and are held together by metallic bonds,

out of the metal powders contained in the metal magnetic powder-containing resin, at least part of the metal powder having a minimum average grain diameter is not covered with a glass coating, and the remaining metal powders are covered with a glass coating,

the metal powder having a minimum average grain diameter comprises two or more kinds of metal powders different in constituent material, and

the two or more kinds of metal powder include an Fe powder and an Ni powder.

2. The coil component according to claim 1, wherein the Ni powder constituting the metal powder having a minimum average grain diameter is covered with a glass coating.

3. The coil component according to claim 1, wherein the metal powders contained in the metal magnetic powder-containing resin are three kinds of metal powders different in average grain diameter.

7. The coil component according to claim 1, wherein a part of the metal powder having a minimum average grain diameter is covered with a glass coating.

4. A coil component comprising:

a coil unit including a substrate and a conductor pattern for planar coil provided on the substrate; and

a metal magnetic powder-containing resin covering the coil unit,

wherein;

the metal magnetic powder-containing resin contains three or more kinds of metal powders different in average grain diameter,

the metal powders are made of pure metal or alloy and are held together by metallic bonds,

out of the metal powders contained in the metal magnetic powder-containing resin, at least part of the metal powder having a minimum average grain diameter is not covered with a resin coating, and the remaining metal powders are covered with a resin coating,

the metal powder having a minimum average grain diameter comprises two or more kinds of metal powders different in constituent material, and

the two or more kinds of metal powders include an Fe powder and an Ni powder.

5. The coil component according to claim 4, wherein the Ni powder constituting the metal powder having a minimum average grain diameter is covered with a resin coating.

6. The coil component according to claim 4, wherein the metal powders contained in the metal magnetic powder-containing resin are three kinds of metal powders different in average grain diameter.

8. The coil component according to claim 4, wherein a part of the metal powder having a minimum average grain diameter is covered with a resin coating.