HOT-FORMING FABRICATION METHOD AND PRODUCT OF MAGNETIC COMPONENT

• US 20100245015A1
• Filed: 09/15/2009
• Published: 09/30/2010
• Est. Priority Date: 03/31/2009
• Status: Abandoned Application

• Current Assignee: Curve Industries Incorporated
• Original Assignee: Curve Industries Incorporated
• Inventors: SHANG, S. R.
• Application Number:
  US12/559,580
• Publication Number:
  US 20100245015A1
• Time in Patent Office: Days
• US Class Current: 336/221
• 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 2017/048 with encapsulating core, e.g. made of resin and magnetic powder
• 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 hot-forming fabrication method of a magnetic component and a hot-formed magnetic component fabricated by the same are provided. More particularly, a magnetic powder hot-forming technique is provided, along with a hot-formed magnetic component fabricated by the hot-forming technique so as to have high inductance, low core loss, and high electromagnetic wave shielding efficiency. A low core low-core loss core for use in a common basic magnetic component is enclosed and thereby shielded by a single-layer or multi-layer EMI shielding material, thus producing an enhanced magnetic component with high inductance, low core loss, and low electromagnetic wave interference.

Claims

1. A hot-forming fabrication method of a magnetic component, comprising steps of:

winding a current-carrying coil around a core so as to form a magnetic energy storage component;

placing the magnetic energy storage component in a mold, and disposing a magnetic shielding material around the magnetic energy storage component; and

performing a hot-forming process so as to obtain a hot-formed magnetic component enclosed by the magnetic shielding material.

2. The hot-forming fabrication method of claim 1, wherein the core comprises a magnetic induction core bar, as one enclosed in a common magnetic component, or is made of a single low loss and high permeability magnetic material or a low loss and high permeability composite magnetic material whose constituent materials possess different magnetic properties.

3. The hot-forming fabrication method of claim 1, wherein the magnetic shielding material comprises a common magnetic shielding material made of a magnetic powder, a binder, and a lubricant uniformly mixed together or comprises a single magnetic material with high EMI shielding efficiency or a composite magnetic material which has good EMI shielding efficiency and whose constituent materials have different magnetic properties.

4. The hot-forming fabrication method of claim 3, wherein the magnetic powder comprises an iron powder selected from the group consisting of SC200, SC100.26 and Beipiao Shenglong BF200.27, BF100.27 or an iron alloy powder (Fe, Al, Si, Cr, Ni, Co), or comprises a mixed powder with similar magnetic permeability selected from the group consisting of Sendust, Amorphous, MPP, and Hi-Flux;

wherein the binder comprises a single specific resin or multiple specific resins, 4% to 20% by weight of the magnetic powder, for binding magnetic particles during the hot-forming process, the single or multiple specific resins comprising a common hot-forming material selected from the group consisting of polycarbonate (PC), polystyrene resin (PS), polyethylene (PE), nylon, and polypropylene (PP) etc.; and

wherein the lubricant, 0.05% to 3% by weight of the magnetic powder, comprises one selected from the group consisting of white wax, molybdenum disulfide, and polytetrafluornethylene (PTFE) etc., for providing lubrication during the hot-forming process and thereby facilitating product release.

5. The hot-forming fabrication method of claim 1, wherein the hot-forming process comprises steps of:

heating the magnetic shielding material to 140 to 350°

C. so as to soften and liquefy the magnetic shielding material; and

pressing the magnetic shielding material with a pressing device, such that the current-carrying coil and the core are enclosed by the magnetic shielding material and thus provided with a complex form feature selected from the group consisting of a bent part, a hollow part, and a delicated-part.

6. A hot-formed magnetic component, comprising:

a core;

a current-carrying coil wound around the core; and

a magnetic shielding material enclosing the core and the current-carrying coil by a hot-forming process.

7. The hot-formed magnetic component of claim 6, wherein the core comprises a magnetic induction core bar, as one enclosed in a common magnetic component, or is made of a single low loss and high permeability magnetic material or a low loss and high permeability composite magnetic material whose constituent materials possess different magnetic properties.

8. The hot-formed magnetic component of claim 6, wherein the magnetic shielding material comprises a common magnetic shielding material made of a magnetic powder, a binder, and a lubricant uniformly mixed together or comprises a single magnetic material with high EMI shielding efficiency or a composite magnetic material which has good EMI shielding efficiency and whose constituent materials have different magnetic properties.

9. The hot-formed magnetic component of claim 6, wherein the magnetic shielding material encloses the current-carrying coil and the core completely or partially, depending on dimensions of the magnetic component.

10. The hot-formed magnetic component of claim 6, wherein a volume ratio between the core and the magnetic shielding material is adjustable so as to achieve desired inductance, core loss, and related electromagnetic properties.

11. The hot-formed magnetic component of claim 6, wherein the core protrudes from the current-carrying coil so as to effectively prevent congestion of magnetic field lines and increase inductance by 20% to 50%.

12. The hot-formed magnetic component of claim 6, wherein the core is T-shaped so as to increase an area of contact between the core and the magnetic shielding material and a volume ratio of the core to the magnetic shielding material, thereby effectively preventing loss of magnetic field lines at a contact surface between the core and the magnetic shielding material while increasing inductance.

13. The hot-formed magnetic component of claim 6, wherein the core has an increased volume proportion so as to significantly increase inductance and lower core loss.

14. The hot-formed magnetic component of claim 6, wherein the core is I-shaped, T-shaped, or columnar etc.