Induction heating system, induction heating method, output monitoring apparatus, output monitoring method, and induction heating apparatus

Patent metadata

Field	Value
Publication number	US-10159117-B2
Application number	US-201314401250-A
Country	US
Kind code	B2
Filing date	May 17, 2013
Priority date	May 18, 2012
Publication date	Dec 18, 2018
Grant date	Dec 18, 2018

Abstract

An induction heating system includes induction heating apparatuses, each including a high-frequency current transformer, a low-frequency current transformer and a heating coil, a high-frequency input switch connected to the high-frequency current transformer, a low-frequency input switch connected to the low-frequency current transformer, a first power source to output a high-frequency electric power and a low frequency electric power, a second power source, a first power source output switch connectable to the first power source, a second power source output switch connectable to the second power source, and a switch controller. Each induction heating apparatus includes a heater controller to send a signal to the switching controller to turn on one of the first power source output switch and the second power source output switch, to turn off the other, and to switch on or off each of the high-frequency input switch and the low-frequency input switch.

First claim

The invention claimed is:

1. An induction heating system comprising:
a plurality of induction heating apparatuses, each of the induction heating apparatuses including a high-frequency current transformer, a low-frequency current transformer, and a heating coil to which a secondary side of the high-frequency current transformer and a secondary side of the low-frequency current transformer are connected in parallel;
a high-frequency input switch connected to a primary side of the high-frequency current transformer of each induction heating apparatus;
a low-frequency input switch connected to a primary side of the low-frequency current transformer of each induction heating apparatus;
a first power source including a high frequency output terminal arranged to be connected to the primary side of the high-frequency current transformer of each induction heating apparatus and a low frequency output terminal arranged to be connected to the primary side of the low-frequency current transformer of each induction heating apparatus,
the first power source including a first power source controller configured to adjust a ratio of a high frequency output time for outputting high frequency electric power and a low frequency output time for outputting low frequency electric power from the first power source during a time period, and to control output of the high frequency electric power and the low frequency electric power from the first power source to each induction heating apparatus according to the adjusted ratio;
a second power source including an output terminal arranged to be connected to the low-frequency current transformers of each induction heating apparatus and including a second power source controller configured to control output of a frequency value of electric power from the second power source to each induction heating apparatus that is different from a frequency value of the electric power output from the first power source to each induction heating apparatus;
a first power source output switch arranged to be connectable to the low-frequency output terminal of the first power source;
a second power source output switch arranged to be connectable to the output terminal of the second power source; and
a switch controller configured to control the high-frequency input switch and the low-frequency input switch for each of the induction heating apparatuses, and to control the first power source output switch and the second power source output switch so as to connect at least one of the induction heating apparatuses to at least one of the first power source and the second power source,
wherein each of the induction heating apparatuses includes a heater controller configured to send a switching request signal for requesting receipt of a source of power for initiating an induction heating operation to the switch controller, the switch controller performing control operations for providing the source of power based on the received switching request signal that includes: to turn on one of the first power source output switch for the first power source and the second power source output switch for the second power source, and to switch on or off each of the high-frequency input switch and the low-frequency input switch to respective induction heating apparatuses.

2. The induction heating system according to claim 1 , wherein, upon receipt of the switching request signal, the switch controller controls the first power source output switch and the second power source output switch and also the high-frequency input switch and the low-frequency input switch that are connected to one of the induction heating apparatuses from which the switching request signal is sent,
the switch controller sends a switching completion signal to the heater controller of the one induction heating apparatus when the switch controller has completed the control in accordance with the switching request signal, and
upon receipt of the switching completion signal by the heater controller of the one induction heating apparatus, the heating controller of the one the induction heating apparatus controls the receipt of power from the first power source and the second power source.

3. The induction heating system according to claim 1 , wherein the low-frequency current transformer includes a core coupling the primary winding and the secondary winding of the low-frequency current transformer,
wherein the low-frequency current transformer is arranged below the high-frequency current transformer, and
wherein each of the induction heating apparatuses is configured such that another heating coil having a different impedance that is attachable, and such that another low-frequency current transformer having a different number of turns of primary and secondary windings that satisfies an impedance matching condition corresponding to the heating coil having the different impedance is attachable.

4. The induction heating system according to claim 3 , wherein each of the induction heating apparatuses further comprises:
a mounting frame supporting the low-frequency current transformer and the high-frequency current transformer; and
a replacing mechanism provided on the mounting frame to replace the low-frequency current transformer,
wherein the replacing mechanism comprises a front-rear direction support extending in a front-rear direction of the mounting frame, and a carriage on which the low-frequency current transformer is mounted and moves on the front-rear direction support in the front-rear direction,
wherein, when the carriage is moved forward with respect to the front-rear direction, the low-frequency current transformer is arranged at a position at which the secondary side of the low-frequency current transformer is connectable to the heating coil, and
wherein, when the carriage is moved backward with respect the front-rear direction, the low-frequency current transformer is arranged at a position at which the low-frequency current transformer does not overlap the high-frequency current transformer in a vertical direction on the mounting frame.

Assignees

• Neturen Co Ltd

Inventors

• Ono Tetsuya
• Sugimoto Masato
• Kiyosawa Yutaka
• Aiba Toshihiro
• Oka Kazutomi
• Ikuta Fumiaki
• Kawasaki Kazuhiro

Classifications

• H05B6/06 Primary

  Control, e.g. of temperature, of power · CPC title

• G01R21/06

  by measuring current and voltage (G01R21/08 - G01R21/133 take precedence) · CPC title

• G01R31/40

  Testing power supplies (testing photovoltaic devices H02S50/10) · CPC title

• H05B6/101

  for local heating of metal pieces · CPC title

• H05B6/04

  Sources of current · CPC title