Toroidal core for a toroid

• US 6,762,666 B2
• Filed: 05/07/2002
• Issued: 07/13/2004
• Est. Priority Date: 05/07/2002
• Status: Expired due to Term

• Current Assignee: Defond Components Limited
• Original Assignee: Defond Manufacturing Limited (Johnson Electric Holdings Limited)
• Inventors: Chu, Raymond Wai Hang
• Primary Examiner(s): MAI, ANH T
• Application Number:
  US10/139,239
• Publication Number:
  US 20030210123A1
• Time in Patent Office: 798 Days
• Field of Search: 336/229, 336/206, 336/178, 336/212, 336/233, 335/210, 335/213, 324/127, 296/021
• US Class Current: 336/229
• CPC Class Codes: H01F 3/14 Constrictions; Gaps, e.g. air-gaps in magnetic shunt paths H01F3/12
• CPC Class Codes: H01F 30/16 Toroidal transformers
• CPC Class Codes: H01F 38/30 Constructions

Abstract

A toroidal core for a toroid, including at least two toroidal rings that are stacked co-axially one upon another. At least one of the two toroidal rings has a body including a gap that forms a break in one side of the body. The gap avoids saturation of the core.

Claims

1. A toroidal core for a toroid, the core

comprising at least two toroidal rings that are stacked co-axially, one upon another, at least a first of the at least two toroidal rings having a body including a gap forming a break in one side of the body;

a non-ferromagnetic filler filling the gap, the filler having an outer surface that lies flush with parts of the body of the first ring forming the gap; and

an insulating coating completely covering the body of the first ring and the filler.

2. The toroidal core as claimed in claim 1, wherein the gap extends substantially radially with respect to the body of the first ring.

3. The toroidal core as claimed in claim 1, wherein the gap has a substantially uniform width.

4. The toroidal core as claimed in claim 1, wherein the gap is formed at the same time as the body of the first ring is moulded in shape.

5. The toroidal core as claimed in claim 1, wherein the at least two toroidal rings have respective bodies which have substantially the same outer and inner diameters as one another.

6. The toroidal core as claimed in claim 1, including only two of the toroidal rings and one of the first toroidal rings.

7. The toroidal core as claimed in claim 1, including at least three of the toroidal rings, wherein the first ring is an intermediate ring in the stack.

8. A toroid incorporating the toroidal core as claimed in claim 1, wherein the toroid includes at least one winding wound on the toroidal core, whereby the at least two toroidal rings are secured together.