Clamp jaw assembly

• US 8,159,211 B2
• Filed: 12/27/2010
• Issued: 04/17/2012
• Est. Priority Date: 08/30/2007
• Status: Active Grant

• Current Assignee: Fluke Corporation (Fortive Corp.)
• Original Assignee: Fluke Corporation (Fortive Corp.)
• Inventors: Wang, Yong, Yang, Yinhong
• Primary Examiner(s): Rodas, Richard Isla
• Application Number:
  US12/979,216
• Publication Number:
  US 20110101960A1
• Time in Patent Office: 477 Days
• Field of Search: 324/127
• US Class Current: 324/127
• CPC Class Codes: G01R 1/22 Tong testers acting as secondary windings of current transformers

Abstract

A clamp jaw assembly for a clamp meter is provided. The clamp jaw assembly comprises a housing containing a clamp jaw core disposed within a shield. The housing, shield, and core of the clamp jaw assembly are configured to provide an extended creepage and clearance path from an exterior of the housing to a surface of the core.

Claims

1. A clamp jaw assembly for a clamp meter, comprising a first clamp jaw movable in relation to a second clamp jaw, each of the first and second clamp jaws having a first end and a second end, said first ends being configured to secure to a body housing, and said second ends being configured to meet so as to define an enclosed area between the first and second clamp jaws;

wherein each of the first and second clamp jaws comprise;

a shield made of a nonconductive material having a channel;

a conductive clamp jaw core positioned, but not permanently fixed, within the channel of the shield, the clamp jaw core having a cross-sectional shape defined by at least first and second exterior surfaces extending between first and second ends of the clamp jaw core, wherein the first exterior surface extending between the first and second ends remains exposed; and

a clamp jaw housing, made of a nonconductive material, enclosing the clamp jaw core and the shield such that the clamp jaw core and shield are not fixed to an interior surface of the camp jaw housing, the clamp jaw housing having top and bottom housings that define an interference connection therebetween extending from an exterior surface of the clamp jaw housing to an interior surface of the clamp jaw housing;

wherein a portion of the shield is positioned between the interference connection and the clamp jaw core; and

wherein the clamp jaw housing, shield, and clamp jaw core are arranged to define a creepage and clearance path that extends from the exterior surface of the clamp jaw housing, along the interference connection to the interior surface of the clamp jaw housing, and towards the first exterior surface of the clamp jaw core exposed by the shield.

2. The clamp jaw assembly of claim 1, wherein at least one of the first and second clamp jaws is arcuate in shape.

3. The clamp jaw assembly of claim 1, wherein the first clamp jaw is configured to be mounted at its first end within the body housing so as to pivot relative to the second clamp jaw, which is configured to be fixedly secured within the body housing.

4. The clamp jaw assembly of claim 1, wherein the shield is made of a semi-rigid material.

5. The clamp jaw assembly of claim 1, wherein the cross-sectional shape of the clamp jaw core is defined by four exterior surfaces extending along the arc length.

6. The clamp jaw assembly of claim 5, wherein the shield includes a first surface extending between first and second sidewalls to define the channel.

7. The clamp jaw assembly of claim 1, further comprising disposing a biasing member between a portion of the shield and the interior surface of the housing.

8. The clamp jaw assembly of claim 7, wherein the biasing member is a sponge.

9. The clamp jaw assembly of claim 7, wherein the biasing member is a spring.

10. The clamp jaw assembly of claim 1, further comprising a circuit for detecting electrical properties of a conductor placed within the enclosed area formed between the first and second clamp jaws.

11. A clamp meter including a clamp jaw assembly, the clamp jaw assembly comprising a first clamp jaw movable in relation to a second clamp jaw, each of the first and second clamp jaws having a first end and a second end, said first ends being secured to a body housing of the claim meter, and said second ends being configured to meet so as to define an enclosed area between the first and second clamp jaws;

wherein each of the first and second clamp jaws comprise;

a shield made of a nonconductive material having a channel;

a conductive clamp jaw core positioned, but not permanently fixed, within the channel of the shield, the clamp jaw core having a cross-sectional shape defined by at least first and second exterior surfaces extending between first and second ends of the clamp jaw core, wherein the first exterior surface extending between the first and second ends remains exposed; and

a clamp jaw housing, made of a nonconductive material, enclosing the clamp jaw core and the camp jaw shield such that the clamp jaw core and shield are not fixed to an interior surface of the housing, the clamp jaw housing having top and bottom housings that define an interference connection therebetween extending from an exterior surface of the clamp jaw housing to an interior surface of the clamp jaw housing;

wherein a portion of the shield is positioned between the interference connection and the clamp jaw core; and

wherein the clamp jaw housing, shield, and clamp jaw core are arranged to define a creepage and clearance path that extends from the exterior surface of the clamp jaw housing, along the interference connection to the interior surface of the clamp jaw housing, and towards the first exterior surface of the clamp jaw core exposed by the shield.