Low-profile transformer

• US 8,310,327 B2
• Filed: 06/11/2007
• Issued: 11/13/2012
• Est. Priority Date: 06/11/2007
• Status: Active Grant

• Current Assignee: Moog Ltd. (Moog Incorporated)
• Original Assignee: Moog Ltd. (Moog Incorporated)
• Inventors: Willers, Michael J., Walsh, Raymond, Simmonds, Christopher
• Primary Examiner(s): Musleh, Mohamad
• Assistant Examiner(s): BAISA, JOSELITO SASIS
• Application Number:
  US12/452,832
• Publication Number:
  US 20100219926A1
• Time in Patent Office: 1,982 Days
• Field of Search: 336/200, 336/223, 336/232, 336/199, 336/205, 336/206, 336/207, 336/208
• US Class Current: 336/200
• CPC Class Codes: H01F 2027/2809 on stacked layers
• CPC Class Codes: H01F 2027/2819 Planar transformers with printed windings, e.g. surrounded by two cores and to be mounted on printed circuit
• CPC Class Codes: H01F 27/06 Mounting, supporting or suspending transformers, reactors or choke coils not being of the signal type
• CPC Class Codes: H01F 27/2804 Printed windings
• CPC Class Codes: H05K 1/141 One or more single auxiliary printed circuits mounted on a main printed circuit, e.g. modules, adapters H05K1/142 and H05K1/147 take precedence
• CPC Class Codes: H05K 1/165 incorporating printed inductors
• CPC Class Codes: H05K 2201/086 for inductive purposes, e.g. printed inductor with ferrite core
• CPC Class Codes: H05K 2201/09063 Holes or slots in insulating substrate not used for electrical connections
• CPC Class Codes: H05K 2203/1572 Processing both sides of a PCB by the same process; Providing a similar arrangement of components on both sides; Making interlayer connections from two sides

Abstract

The present invention provides an improved transformer (20), which broadly includes: a substrate (21) having first and second surfaces (22, 23); a first board (24) mounted on the substrate first surface; a second board (25) mounted on the substrate second surface; the boards being identical to one another and being mounted on the respective proximate substrate surfaces as mirror images of one another; each of the boards having a plurality of dielectric layers with electrically-conductive sheet windings (35, 36, 37, 38) embedded therein; and an assembled core (26, 28) operatively arranged to provide a path for magnetic flux attributable to a current in some of the windings. Third and fourth boards (71, 72) may be piggy-backed onto the first and second boards, respectively, to selectively vary the properties of the transformer.

Claims

1. A transformer, comprising:

a substrate having first and second surfaces;

a first board mounted on said substrate first surface;

a second board mounted on said substrate second surface;

said first and second boards being identical to one another and being mounted on the respective proximate substrate surfaces as mirror images of one another;

each of said first and second boards having a plurality of dielectric layers with electrically-conductive sheet windings embedded therein;

said sheet windings being electrically connected;

a core operatively arranged to provide a path for magnetic flux attributable to a current in said windings; and

wherein each of said first and second boards has at least three terminals on a surface thereof that are electrically connected to at least one winding within such board and that are operatively arranged to allow different voltages to be tapped off.

2. A transformer as set forth in claim 1, wherein at least one winding of said first board is connected in series with at least one winding of said second board.

3. A transformer as set forth in claim 2, wherein said series-connected windings form a part of the primary windings of said transformer.

4. A transformer as set forth in claim 1, wherein at least one, winding of said first board is connected in parallel with at least one winding of said second board.

5. A transformer as set forth in claim 4, wherein said parallel-connected windings form a part of the secondary windings of said transformer.

6. A transformer as set forth in claim 1, wherein at least one winding of said first board is independent of all other windings.

7. A transformer as set forth in claim 1, wherein at least one, winding of said second board is independent of all other windings.

8. A transformer as set forth in claim 1, wherein said core is formed by assembling two core portions, wherein a first of said core portions is arranged proximate said first board, and wherein a second of said core portions is arranged proximate said second board.

9. A transformer as set forth in claim 8, wherein at least one of said core portions is E-shaped.

10. A transformer as set forth in claim 8, wherein at least one of said core portions is I-shaped.

11. A transformer as set forth in claim 1, wherein said substrate is a printed circuit board.

12. A transformer as set forth in claim 11, wherein at least one of said transformer windings is located within said printed circuit board.

13. A transformer as set forth in claim 1, wherein said first and second boards are formed by a printed circuit technique.

14. A transformer as set forth in claim 1, wherein different windings within a board are connected by vias.

15. A transformer as set forth in claim 1, wherein at least one winding of said first board is connected to at least one winding of said second board by at least one via.

16. A transformer as set forth in claim 1, and further comprising a third board mounted on said first board and electrically connected thereto, and wherein at least one winding of said third board is electrically connected to at least one winding of said first board.

17. A transformer as set forth in claim 1, and further comprising a fourth board mounted on said second board and electrically connected thereto, and wherein at least one winding of said fourth board is electrically connected to at least one winding of said second board.

18. A transformer as set forth in claim 17, wherein said third and fourth boards are identical.

19. A transformer as set forth in claim 17, wherein said third and fourth boards are not identical to said first and second boards.

20. A transformer as set forth in claim 18 wherein said third and fourth boards are mounted on said first and second boards, respectively, as mirror images of one another.

21. A transformer as set forth in claim 17, wherein said third and fourth boards each have at least three terminals on a surface thereof that are electrically connected to at least one winding with such board, and that are operatively arranged to allow different voltages to be tapped off.

22. A transformer as set forth in claim 17, wherein at least one winding of said third board is connected in parallel with at least one winding of said first board, and wherein at least one winding of said fourth board is connected in parallel with at least one winding of said second board.

23. A transformer as set forth in claim 17, wherein at least one winding of said third board is connected in series with at least one winding of said first board, and wherein at least one winding of said fourth board is connected in series with at least one winding of said second board.

24. A transformer as set forth in claim 1, wherein each board contains groups of terminations associated with the windings of that particular board.

25. A transformer as set forth in claim 24, wherein the group of terminations on one board is arranged to provide adequate voltage clearance relative to the group of terminations on an adjacent board.