SYSTEM AND METHOD FOR MEASURING INPUT ENERGY FOR AN INDUCTION HEATING INSTALLATION

• US 3,746,825 A
• Filed: 09/30/1971
• Issued: 07/17/1973
• Est. Priority Date: 09/30/1971
• Status: Expired due to Term

• Current Assignee: George D. Pfaffmann
• Original Assignee: George D. Pfaffmann
• Inventors: Pfaffmann, George D.
• Primary Examiner(s): Truhe, J. V.
• Assistant Examiner(s): Reynolds, B. A.
• Application Number:
  US05/185,316
• Time in Patent Office: 656 Days
• Field of Search: 219/10.77,10.75,109,110 323/20
• US Class Current: 219/665
• CPC Class Codes: G01R 21/08 by using galvanomagnetic-effect devices, e.g. Hall-effect devices
• CPC Class Codes: H05B 6/06 Control, e.g. of temperature, of power

Abstract

A system and method for measuring the energy applied to a workpiece in an induction heating installation which includes creating a power signal representative of the instantaneous power supplied to the workpiece and means for integrating the power signal with respect to time to create a resultant signal representative of the accumulated energy applied to the workpiece.

Claims

1. A system for measuring the energy applied to a workpiece in an induction heating installation including a power supply, a coupling transformer with a primary and a secondary, an output circuit having a first portion connected to said power supply and including said primary and a second portion including said secondary, and an inductor connected to said second portion and magnetically coupled to said workpiece, said system comprising means for sensing the voltage in said second portion of said output circuit, means for sensing the current in said second portion of said output circuit, means for creating a D.C. voltage signal representative of the product of said sensed voltage and current and having a level proportional to the sensed current and voltage in said output circuit, means for integrating sAid voltage signal with respect to time to create a resultant signal of increasing slope function representative of energy input to said workpiece, control means responsive to said resultant signal, said control means including means for interrupting power to said inductor, and said interrupting means including means for disconnecting said power supply from said output circuit when said resultant signal reaches a preselected value.