Inductance device

• US 7,183,886 B2
• Filed: 09/14/2005
• Issued: 02/27/2007
• Est. Priority Date: 03/28/2003
• Status: Expired due to Fees

• Current Assignee: Sumida Corporation, Sumika Technology Company Limited (Sumitomo Chemical Company Limited)
• Original Assignee: Sumida Corporation, Sumika Technology Company Limited (Sumitomo Chemical Company Limited)
• Inventors: Ooki, Juichi
• Primary Examiner(s): Nguyen; Tuyen T.
• Application Number:
  US11/225,160
• Publication Number:
  US 20060006970A1
• Time in Patent Office: 531 Days
• Field of Search: 336/65, 336/83, 336/200, 336206-208, 336/232
• US Class Current: 336/83
• 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 27/022 Encapsulation
• CPC Class Codes: H01F 27/292 Surface mounted devices
• CPC Class Codes: H01F 27/33 Arrangements for noise damping
• CPC Class Codes: H01F 27/36 Electric or magnetic shields or screens movable for varying inductance H01F21/10
• CPC Class Codes: H01F 27/366 made of ferromagnetic material
• CPC Class Codes: H01F 3/10 Composite arrangements of magnetic circuits
• CPC Class Codes: H01F 3/12 Magnetic shunt paths
• CPC Class Codes: H01F 3/14 Constrictions; Gaps, e.g. air-gaps in magnetic shunt paths H01F3/12

Abstract

An inductance device comprises a drum core having a center core, and flanges integrated therewith. The center core is wound with a wire, whereas a magnetic gap is formed between the upper flange and lower flange. The magnetic gap is closed with an insulator, mixed with a magnetic substance, having rubber elasticity. The insulator comprises an overhang and an insertion integrally formed therewith. The overhang presses a region in the upper flange so as to hang from this region. The insertion tightly fits into the magnetic gap.

Claims

1. An inductance device comprising:

a drum core having;

a center core wound with a wire,

upper flange and lower flange, formed at both ends of said center core,

a magnetic gap between said upper flange and lower flange, and

an insulator;

being mixed with a magnetic substance, the weight of said magnetic substance being at a predetermined ratio of 60% to 90% lower than that of the weight of an insulating material,

having rubber elasticity and having an endless form, and

fitting into said magnetic gap;

wherein a placement of an outer face part of said insulator is outward from that of an outer circumferential side face part of said upper flange and lower flange of said drum core.

2. An inductance device according to claim 1, wherein said insulator is made of silicone rubber.

3. An inductance device according to claim 2, wherein said magnetic gap has an outer face side which is completely enclosed with the insulator.

4. An inductance device according to claim 3, wherein said insulator is made of silicone rubber.

5. An inductance device according to claim 4, wherein said insulator is tightly inserted into a magnetic gap between said upper flange and said lower flange.

6. An inductance device according to claim 5, wherein said insulator comprises a rubber ring having a peripheral part extending from a peripheral part of an upper face of said upper flange.

7. An inductance device according to claim 1, wherein said insulator comprises:

an overhang which extends outward from said outer circumferential side face part of said upper flange and lower flange of said drum core while in contact therewith; and

an insertion portion integrally formed therewith, which is inserted into said magnetic gap.

8. An inductance device according to claim 7, wherein said insulator is made of silicone rubber.

9. An inductance device according to claim 7, wherein said magnetic gap outer face side is completely enclosed with an insulator.

10. An inductance device according to claim 9, wherein said insulator is made of silicone rubber.

11. An inductance device according to claim 9, wherein said insulator is tightly inserted into a magnetic gap between said upper flange and lower flange.

12. An inductance device according to claim 9, wherein said insulator comprises a rubber ring having a peripheral part extending from a peripheral part of an upper face of said upper flange.