Current measurement using inductor coil with compact configuration and low TCR alloys

• US 20060049907A1
• Filed: 06/20/2005
• Published: 03/09/2006
• Est. Priority Date: 09/08/2004
• Status: Active Grant

• Current Assignee: Cyntec Co. Ltd. (Delta Electronics Incorporated)
• Original Assignee: Cyntec Co. Ltd. (Delta Electronics Incorporated)
• Inventors: Liu, Chun-Tiao
• Granted Patent: US 7,667,565 B2
• Time in Patent Office: Days
• US Class Current: 336/200
• CPC Class Codes: H01F 17/04 with magnetic core
• CPC Class Codes: H01F 2017/046 helical coil made of flat wire, e.g. with smaller extension of wire cross section in the direction of the longitudinal axis
• CPC Class Codes: H01F 2017/048 with encapsulating core, e.g. made of resin and magnetic powder
• CPC Class Codes: H01F 27/027 specially adapted for combination of signal type inductors or transformers with electronic circuits, e.g. mounting on printed circuit boards
• CPC Class Codes: H01F 27/255 made from particles H01F27/26 takes precedence
• CPC Class Codes: H01F 27/2828 Construction of conductive connections, of leads
• CPC Class Codes: H01F 27/292 Surface mounted devices

Abstract

This invention discloses an inductor that includes a conducting wire composed of an alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or is lower. The inductive coil has a winding configuration provided for enclosure in a substantially rectangular box with a mid-plane extended along an elongated direction of the rectangular box wherein the conducting wire interesting at least twice near said mid-plane.

Claims

1. An inductor comprising:

a conducting wire composed of an alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

2. The inductor of claim 1 wherein:

said conducting wire having a winding configuration provided for enclosure in a substantially rectangular box.

3. The inductor of claim 2 wherein:

said conducting wire is molded in a magnetic bonding material comprising powdered particles with a diameter smaller than ten micrometers and coated with an insulation layer.

4. The inductor of claim 3 wherein:

said powdered particles of said magnetic bonding material comprising carbonyle iron particles.

5. The inductor of claim 3 wherein:

said insulation layer comprising a layer with a resistance substantially greater than 1M ohms.

6. The inductor of claim 3 wherein:

said insulation layer comprising a layer with a resistance about 10M ohms.

7. The inductor of claim 3 wherein:

said insulation layer comprising a polymer layer.

8. The inductor of claim 3 wherein:

said insulation layer comprising a sol gel layer.

9. The inductor of claim 1 wherein:

said conducting wire having a winding configuration with a mid-plane extended along an elongated direction of said rectangular box wherein said conducting wire interesting at least twice near said mid-plan provided for enclosure in a substantially rectangular box.

10. The inductor of claim 1 wherein:

said conducting wire having a first flattened terminal end and a second flattened terminal end for extending out from an enclosure housing to function as a first and second electrical terminals to connect to an external circuit.

11. The inductor of claim 1 wherein:

said conducting wire having a first welding terminal and a second welding terminal for extending out from an enclosure housing for welding to a lead frame.

12. The inductor of claim 1 wherein:

said conducting wire composed of a Cu—

Mn—

Ni alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

13. The inductor of claim 1 wherein:

said conducting wire composed of a Ni—

Cr alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

14. The inductor of claim 1 wherein:

said conducting wire composed of a Fe—

Cr—

Al alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

15. The inductor of claim 1 wherein:

said conducting wire composed of a Cu—

Ni alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

16. The inductor of claim 1 wherein:

said conducting wire composed of a Fe—

Cr alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

17. A method for manufacturing an inductor comprising:

winding a conducting wire composed of an alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

18. The method of claim 18 further comprising:

molding said conducting wire in a magnetic bonding material comprising powdered particles with a diameter smaller than ten micrometers and coated with an insulation layer.

29. The method of claim 18 wherein:

said step of winding a conducting wire further comprising a step of winding a wire composed of a Cu—

Mn—

Ni alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

30. The method of claim 18 wherein:

said step of winding a conducting wire further comprising a step of winding a wire composed of a Ni—

Cr alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

31. The method of claim 18 wherein:

said step of winding a conducting wire further comprising a step of winding a wire composed of a Fe—

Cr—

Al alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

32. The method of claim 18 wherein:

said step of winding a conducting wire further comprising a step of winding a wire composed of a Cu—

Ni alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

33. The inductor of claim 18 wherein:

said step of winding a conducting wire further comprising a step of winding a wire composed of a Fe—

Cr alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

19. The method of claim 19 wherein:

said step of winding said conducting wire further comprising a step of winding said conducting wire with a winding configuration provided for enclosure in a substantially rectangular box

20. The method of claim 19 wherein:

said step of bonding said conducting wire in a magnetic bonding material comprising powdered particles further comprising a step of molding said conducting wire in said magnetic bonding material comprising powdered carbonyle iron particles.

21. The method of claim 19 wherein:

said step of bonding said conducting wire in said powdered particles coated with said insulation layer further comprising a step of molding said conducting wire in said powdered particles coated with an insulation layer with a resistance substantially greater than 1M ohms.

22. The method of claim 19 wherein:

said step of bonding said conducting wire in said powdered particles coated with said insulation layer further comprising a step of molding said conducting wire in said powdered particles coated with an insulation layer with a resistance about 10M ohms.

23. The method of claim 19 wherein:

said step of bonding said conducting wire in said powdered particles coated with said insulation layer further comprising a step of molding said conducting wire in said powdered particles coated with a polymer insulation layer.

24. The method of claim 19 wherein:

said step of bonding said conducting wire in said powdered particles coated with said insulation layer further comprising a step of molding said conducting wire in said powdered particles coated with a sol gel insulation layer.

25. The method of claim 19 wherein:

said step of winding a conducting wire further comprising a step of winding said conducting wire with a winding configuration provided for enclosure in a substantially rectangular box.

26. The method of claim 19 wherein:

said step of winding a conducting wire further comprising a step of winding said conducting wire having a winding configuration with a mid-plane extended along an elongated direction of said rectangular box wherein said conducting wire interesting at least twice near said mid-plan provided for enclosure in a substantially rectangular box.

27. The method of claim 19 further comprising:

flattening a first end of said conducting wire for providing a first flattened terminal end and flattening a second end of said conducting wire for providing a second flattened terminal end for extending out from an enclosure housing to function as a first and second electrical terminals to connect to an external circuit.

28. The method of claim 19 further comprising:

preparing a first end of said conducing wire as a first welding terminal and preparing a second end of said conducting wire as a second welding terminal for extending out from an enclosure housing for welding to a lead frame.

34. An electric apparatus comprising:

an inductor comprising a conducting wire composed of an alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower whereby a current can be measured directly over said inductor.

35. The electric apparatus of claim 34 further comprising:

a voltage converter connected to said inductor.

36. The electric apparatus of claim 34 wherein:

said conducting wire composed of a Cu—

Mn—

Ni alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

37. The electric apparatus of claim 34 wherein:

said conducting wire composed of a Ni—

Cr alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

38. The electric apparatus of claim 34 wherein:

said conducting wire composed of a Fe—

Cr—

Al alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

39. The electric apparatus of claim 34 wherein:

said conducting wire composed of a Cu—

Ni alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.

40. The electric apparatus of claim 34 wherein:

said conducting wire composed of a Fe—

Cr alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or lower.