SURFACE MOUNT MAGNETIC COMPONENT ASSEMBLY

• US 20100007451A1
• Filed: 04/24/2009
• Published: 01/14/2010
• Est. Priority Date: 07/11/2008
• Status: Active Grant

• Current Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Original Assignee: Cooper Technologies Company (Eaton Corporation PLC.)
• Inventors: Bogert, Robert James, Yan, Yipeng
• Granted Patent: US 7,986,208 B2
• Time in Patent Office: Days
• US Class Current: 336/90
• CPC Class Codes: H01F 17/043 with two, usually identical or nearly identical parts enclosing completely the coil (pot cores)
• CPC Class Codes: H01F 2017/048 with encapsulating core, e.g. made of resin and magnetic powder
• CPC Class Codes: H01F 2027/065 Mounting on printed circuit boards
• CPC Class Codes: H01F 27/263 Fastening parts of the core together
• CPC Class Codes: H01F 27/2828 Construction of conductive connections, of leads
• CPC Class Codes: H01F 27/292 Surface mounted devices

Abstract

A surface mount magnetic component assembly including a magnetic core having a side with a stepped external surface, a coil within the magnetic core, and terminal clips for making electrical connections to the ends of the coil. The ends of the coil extend through the stepped external surface, the terminal clips attach to the stepped external surface, and the external surface is mounted to a circuit board to complete electrical connection with improved reliability. Smaller component sizes with improved manufacturability and consistency result.

Claims

1. A surface mount magnetic component assembly comprising:

a magnetic core defining at least one external side having a stepped surface; and

a conductive coil internal to the magnetic core, the coil including first and second ends; and

at least one of the first and second ends extending through the at least one side.

2. The magnetic component assembly of claim 1, wherein the stepped surface comprises a first surface and a second surface;

and

wherein the second surface is depressed relative to the first surface.

3. The magnetic component assembly of claim 2, wherein the at least one side has a first end, a second end opposing the first end, and the second surface extending entirely between the first end and the second end.

4. The magnetic component assembly of claim 2, further comprising a third surface extending opposite the second surface with the first surface separating the second and third surfaces.

5. The magnetic component assembly of claim 4, the second and third surfaces being substantially coplanar.

6. The magnetic component assembly of claim 1, the at least one side having a corner, and a through-hole extending through the at least one side proximate the corner.

7. The magnetic component assembly of claim 1, wherein the stepped surface comprises a first surface, a second surface and a third surface, wherein the second surface is depressed relative to the first surface and wherein the third surface is depressed relative to the second surface.

8. The magnetic component assembly of claim 7, wherein the at least one side has a first corner and a second corner, the third surface located proximate the first corner and the second surface extending from the third surface to the second corner.

9. The magnetic component assembly of claim 8, wherein the at least one side has a third corner diagonally opposed to the first corner, the at least one side comprising a fourth surface extending generally coplanar to the third surface, the fourth surface located proximate the third corner.

10. The magnetic component of assembly claim 7, wherein the stepped surface further comprises a fourth surface extending generally coplanar to the third surface, the third and fourth surface being separated by the first surface.

11. The magnetic component assembly of claim 1, wherein the magnetic core comprises a first core piece and a second core piece, one of the first and second core piece defining the at least one external side.

12. The magnetic component assembly of claim 11, wherein the first core piece comprises a base wall and upstanding side walls extending from the base wall.

13. The magnetic component assembly of claim 12, wherein the second core piece is substantially planar.

14. The magnetic component assembly of claim 1, wherein the magnetic core comprises a base wall, a first side wall extending from the base wall, and a second side wall extending from the base wall;

and

wherein the first and second side walls are gapped to provide a window in the core.

15. The magnetic component assembly of claim 14, wherein the window is located proximate a corner of the base wall.

16. The magnetic component assembly of claim 1, further comprising at least one terminal clip configured for attachment to the stepped surface of the core.

17. The magnetic component assembly of claim 16, wherein the at least one terminal clip includes a bottom section extending in a first plane and a coil section extending in a second plane, the first and second plane being parallel to but spaced from one another.

18. The magnetic component assembly of claim 17, wherein the coil section extends internal to the core.

19. The magnetic component assembly of claim 18, wherein the at least one terminal clip defines a slot and a portion of the core being received in the slot between the bottom section and the coil section.

20. The magnetic component assembly of claim 17, wherein the at least one terminal clip comprises first and second terminal clips, the first and second clips being reversed 180°

relative to one another when attached to the core and coil.

21. The magnetic component assembly of claim 17, wherein the at least one terminal clip comprises a third section generally coplanar to the coil section but separated from the terminal section by the bottom section.

22. The magnetic component assembly of claim 16, wherein the terminal clip defines a through hole, and one of the first and second ends of the coil is received in the through hole.

23. The magnetic component assembly of claim 16, wherein the magnetic core includes a second side adjoining the first side, the second side including a recess adjacent the first side, and the at least one terminal clip including a locating tab engaged in the recess.

24. The magnetic component assembly of claim 16, wherein the at least one terminal clip comprises a first terminal clip and a second terminal clip, and wherein the first and second ends of the coil attach to the first and second terminal clips, respectively, without wrapping the first and second ends of the coil around the clips.

25. The magnetic component assembly of claim 1, wherein the coil includes a winding portion between the first and second ends, the winding portion comprising a plurality of turns about a winding axis, and the first and second ends extending generally parallel to the winding axis.

26. The magnetic component assembly of claim 25, wherein the coil comprises one of a flat wire and a round wire wound for a number of turns.

27. The magnetic component assembly of claim 25, wherein the winding extends helically and spirally about the coil axis.

28. The magnetic component assembly of claim 1, further comprising a circuit board, wherein a portion of the stepped surface rests upon the circuit board.

29. The magnetic component of claim 28, further comprising first and second terminal clips, the first and second terminal clips connected to a circuit path on the surface of the board and also respectively connected to the first and second ends of the coil.

30. The magnetic component of claim 29, the first and second terminals each including a planar bottom section connecting to the circuit path, and a coil section extending in a plane parallel to, but spaced from the planar bottom section.

31. The magnetic component of claim 1, wherein the component is an inductor.

32. A surface mount magnetic component assembly comprising:

a magnetic core defining at least one external side with first, second, third and fourth corners and having a stepped surface;

a conductive coil internal to the magnetic core, the coil including first and second ends, at least one of the first and second ends extending through the at least one external side; and

first and second terminal clips coupled to the stepped surface and respectively connecting to the first and second ends of the coil.

33. The magnetic component assembly of claim 32, wherein the core defines at least one window proximate one of the first, second, third and fourth corners for connecting one of the first and second coil leads to the one of the first and second terminal clips at a location interior to the core.

34. The magnetic component assembly of claim 32, wherein each of the first and second terminal clips includes a bottom section extending in a first plane and a coil section extending in a second plane, the second plane being parallel to but spaced from the first plane.

35. The magnetic component assembly of claim 32, wherein the first and third corners are diagonally opposite one another, and the coil sections of each of the first and second terminal clip are proximate the first and third corners.

36. The magnetic component assembly of claim 32, wherein the coil comprises one of a flat wire and around wire wound about an axis for a number of turns.

37. The magnetic component assembly of claim 32, further comprising a circuit board, the external side being surface mounted to the circuit board.

38. The magnetic component of claim 32, wherein at least one of the first and second terminal clips is bilaterally asymmetrical.

39. The magnetic component assembly of claim 32, wherein the component is an inductor.