Common mode/differential mode choke

• US 20020175571A1
• Filed: 04/11/2001
• Published: 11/28/2002
• Est. Priority Date: 04/11/2001
• Status: Active Grant

• Current Assignee: Rockwell Technologies, LLC
• Original Assignee: Rockwell Technologies, LLC
• Inventors: Gilmore, Thomas P., Ray, Glenn
• Granted Patent: US 6,617,950 B2
• Time in Patent Office: Days
• US Class Current: 310/45
• CPC Class Codes: H01F 17/062 Toroidal core with turns of coil around it
• CPC Class Codes: H01F 3/10 Composite arrangements of magnetic circuits
• CPC Class Codes: H01F 37/00 Fixed inductances not covered by group H01F17/00
• CPC Class Codes: H02M 1/123 Suppression of common mode voltage or current
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor

Abstract

A common mode and differential mode inductance assembly including first and second torridial cores wherein first and second windings are wrapped about first and second segments of the first core and the first core forms a first surface and wherein the second core forms a second surface and is positioned adjacent the first core such that the first and second surfaces oppose each other and a gap is formed between the first and second surfaces.

Claims

1. An electromagnetic assembly having improved damping characteristics and comprising:

a first torridial core of magnetic material having at least first and second core segments and forming a first surface;

a fist winding encircling the first core segment;

a second winding encircling the second core segment, the first and second winding segments wrapped in the same direction about the core segments; and

a second torridial core forming a second surface and secured proximate the first torridial core and outside the windings such that the first and second surfaces oppose each other and form an air gap there between.

2. The assembly of claim 1 wherein the first torridial core provides a common mode inductance and wherein the first and second cores and the gap provide a damped differential mode inductance.

3. The assembly of claim 1 wherein the torridial cores are secured together by an epoxy.

4. The assembly of claim 3 wherein the epoxy fills the space within the first torridial core.

5. The assembly of claim 4 wherein the epoxy fills the space within the second torridial core.

6. The assembly of claim 4 wherein the epoxy forms at least one mounting aperture within the first torridial core.

7. The assembly of claim 1 further including an insulative spacer between the first and second cores.

8. The assembly of claim 1 wherein the first core includes a ribbon of metallic material wrapped in torrid form.

9. The assembly of claim 8 wherein the first torrid is coated with an insulating varnish binder material.

10. The assembly of claim 8 wherein the second core includes a ribbon of metallic material wrapped in torrid form.

11. The assembly if claim 1 wherein the first torridial core is formed about an axis and the first surface is perpendicular to the axis.

12. The assembly of claim 1 wherein the first surface is the internal surface of the first torridial core and the second torridial core is positioned within the first torridial core.

14. The method of claim 14 wherein the step of providing the second torridial core includes providing the second torridial core adjacent the first torridial core.

15. The method of claim 14 wherein the step of providing the second torridial core includes providing the second core within the first torridial core.

16. The method of claim 14 wherein the step of providing the second torridial core includes providing the second core about the first torridial core so that the first core is within the second.

17. The method of claim 14 wherein the step of providing the second core includes epoxying the second core to the first core.

18. The method of claim 18 further including the step of, prior to epoxying, providing a spacer between the first and second cores.

13. A method for forming an electromagnetic assembly having improved damping characteristics, the method comprising the steps of:

providing a first torridial core of magnetic material having at least first and second core segments, the first torridial core forming a first surface;

winding a first winding about the first core segment;

winding a second winding about the second core segment; and

providing a second torridial core adjacent the first torridial core such that a second surface formed by the second core opposes the first surface and the first and second surfaces form a gap there between.