D.-c. clamp-on meter including a hall plate flux detector

• US 3,199,026 A
• Filed: 05/01/1961
• Issued: 08/03/1965
• Est. Priority Date: 05/01/1961
• Status: Expired due to Term

• Current Assignee: Donald Leibowitz
• Original Assignee: Donald Leibowitz
• Inventors: Leibowitz, Donald
• Application Number:
  US04/106,759
• Time in Patent Office: 1,555 Days
• US Class Current: 324/127
• CPC Class Codes: G01R 1/22 Tong testers acting as secondary windings of current transformers
• CPC Class Codes: G01R 15/202 using Hall-effect devices Hall elements in arrangements for measuring electrical power G01R21/08

Claims

1. A D.-C. AMMETER, COMPRISING IN COMBINATION, A HANDLE HAVING AN OPENING LENGTHWISE THERETHROUGH;

A FIXED CLAMP HOLDER AFFIXED TO SAID HANDLE;

A MOVEABLE CLAMP HOLDER, PIVOTALLY AFFIXED TO SAID HANDLE;

THUMB ACTUATION PRESSURE MEANS ON SAID MOVEABLE CLAMP HOLDER ADAPTED WHEN PRESSED TO PIVOTALLY MOVE SAID CLAMP HOLDER TO AND AWAY FROM SAID FIXED CLAMP HOLDER;

SPRING MEANS TENDING TO MAINTAIN SAID MOVEABLE CLAMP HOLDER TOWARDS SAID FIXED CLAMP HOLDER;

INNER AND OUTER MAGNETIC POLE PIECES HELD BY SAID FIXED CLAMP HOLDER, BOTH HAVING ARCUATE POLE FACES ADAPTED TO PARTIALLY ENCIRCLE A CABLE, THE OUTER FIXED POLE PIECE INCLUDING ONE MEMBER OF A PAIR OF INTERLEAVING MATING MEMBERS;

A PIVOTING MAGNETIC POLE PIECE HAVING AN ARCUATE SHAPED FACE COOPERATING WITH SAID FIXED POLE PIECES ARCUATE FACES SO AS TO ENCIRCLE A CABLE BETWEEN AN SAID FACES, AND HAVING THE OTHER MEMBER OF SAID PAIR OF INTERLEAVING MATING MEMBERS;

A RECTANGULAR HALL CRYSTAL DISPOSED BETWEEN SAID INNER AND OUTER FIXED POLE FACES SO THAT ONE EDGE THEREOF IS PARALLEL TO A CABLE ENCIRCLED BY SAID POLE FACES, SAID HALL CRYSTAL HAVING OUTPUT LEADS;

HALL CRYSTAL EXCITATION LEADS PASSING THROUGH SAID HANDLE OPENING TO OPPOSED SIDES OF SAID CRYSTAL SO AS TO SEND A HALL EXCITATION CURRENT THERETHROUGH AT RIGHT ANGLES TO THE MAGNETIC FIELD CREATED BY A CURRENT CARRYING CABLE ENCIRCLED BY SAID POLE FACES;

WHEREBY WHEN AN EXCITATION CURRENT SOURCE FEEDS AN EXCITATION CURRENT THROUGH SAID HALL CRYSTAL, THE MAGNETIC FIELD CREATED BY A CURRENT CARRYING CABLE ENCIRCLED BY SAID POLE FACES WILL CAUSE A MEASUREABLE HALL VOLTAGE DROP ACROSS SAID CRYSTAL AT RIGHT ANGLES TO SAID EXCITATION CURRENT AND SAID MAGNETIC FIELD TO PROVIDE A SIGNAL IN SAID OUTPUT LEADS, CORRESPONDING TO THE MAGNITUDE OF THE D.-C. CURRENT PASSING THROUGH SAID CABLE.