JP2011060631A - Induction heating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive induction heating device capable of controlling a heating zone. <P>SOLUTION: The induction heating device has an inverter circuit 102 for creating high-frequency power of a designated frequency and for output thereof, a heating coil 101 for generating a magnetic field at the designated frequency with the high-frequency power supplied from the inverter circuit 102 and performing induction heating of a heated object, and a self-resonant coil 103 arranged between the heated object and the heating coil 101. The self-resonant coil 103 is formed by a resonance coil and a resonant capacitor, and a heating zone of the induction heating device can be controlled by making self-resonance with the frequency of a magnetic field emitted from the heating coil 101. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an induction heating device used in general households, restaurants, factories, and the like.

  In recent years, induction heating cookers typified by IH cooking heaters are widely used in homes. In an induction heating cooker, it is required to be able to sufficiently heat regardless of the size of an object to be heated. For that purpose, the function which can change a heating area | region freely in an induction heating cooking appliance is required. Conventionally, a heating region has been controlled by arranging a plurality of heating coils and an inverter circuit and selecting a coil to be fed (see, for example, Patent Document 1).

JP 2006-230517 A

  However, in the above conventional configuration, a plurality of inverter circuits connected to the heating coil are necessary, and when the inverter circuit is shared by one circuit, the circuit for switching the power supply becomes very complicated and the cost is high. There was a problem.

  In view of the above-described conventional problems, an object of the present invention is to provide an inexpensive induction heating apparatus that can control a heating region.

  In order to solve the above problems, an induction heating apparatus of the present invention generates a high frequency power having a predetermined frequency and outputs an inverter circuit, and generates a magnetic field having a predetermined frequency by the high frequency power supplied from the inverter circuit. A heating coil for inductively heating the object to be heated, and a self-resonant coil installed between the object to be heated and the heating coil, the self-resonant coil comprising a resonance coil and a resonance capacitor, It is an induction heating device that self-resonates at the frequency of the magnetic field generated by.

  Thereby, an inexpensive induction heating apparatus capable of controlling the heating region can be realized.

  The induction heating device of the present invention can realize an inexpensive induction heating device capable of controlling the heating region.

The figure which shows the structure of the induction heating apparatus in Embodiment 1 of this invention.

A first invention is an inverter circuit that generates and outputs high-frequency power of a predetermined frequency, and a heating coil that generates a magnetic field of a predetermined frequency by the high-frequency power supplied from the inverter circuit and induction-heats an object to be heated And a self-resonant coil installed between the object to be heated and the heating coil, wherein the self-resonant coil is composed of a resonance coil and a resonance capacitor, and induces self-resonance at the frequency of the magnetic field generated by the heating coil. It is a heating device.
With this configuration, heating by the self-resonant coil can be realized.

According to a second invention, in the induction heating device of the first invention, the self-resonant coil is composed of a plurality of self-resonant coils each having a different resonance frequency, and the frequency of the high-frequency power output from the inverter circuit is controlled. The induction heating device controls the heating region by changing the frequency of the magnetic field generated by the heating coil.
With this configuration, the heating area of the object to be heated can be controlled by the frequency.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a diagram showing the configuration of the induction heating apparatus of the present invention.

  The heating coil 101 is connected to an inverter circuit 102 that generates and outputs high-frequency power with a predetermined frequency at both ends, generates a high-frequency magnetic field with a predetermined frequency, induces a current in a self-resonant coil 103 described later, and is insulated. This is a heating coil that induction-heats the object to be heated 105 via a top plate 104 formed of a body.

  The self-resonant coil 103 is installed between the object to be heated 105 and the heating coil 101, and includes a first resonance coil 201, a second resonance coil 202, a third resonance coil 203 having an inductance component, and a first component having a capacitance component. The first resonance capacitor 204, the second resonance capacitor 205, and the third resonance capacitor 206 are composed of an inductance component and a capacitance component, respectively, and cause self-resonance at a specific frequency. The first resonance coil 201 and the first resonance capacitor 204, the second resonance coil 202 and the second resonance capacitor 205, and the third resonance coil 203 and the third resonance capacitor 206 have different self-resonance frequencies. Adjust the inductance and capacitance values.

  Further, the self-resonance frequency may be adjusted by adjusting the mutual inductance generated between the respective resonance coils.

  In FIG. 1, a plurality of resonance coils are concentrically arranged. However, the central axes do not have to be the same, and any arrangement is possible as long as they are installed between the object to be heated 105 and the heating coil 101. Good.

  Further, self-resonance may be performed using a parasitic capacitance component of the resonance coil. In this case, a resonance capacitor is not necessary.

  About the induction heating apparatus of this invention comprised as mentioned above, the operation | movement and an effect | action are demonstrated. When the frequency of the electric power input to the heating coil 101 is changed by the inverter circuit 102, self-resonance is caused only in the resonance coil whose frequency matches the self-resonance frequency, and current is induced. This current generates a high-frequency magnetic field in the resonance coil, and the object to be heated 105 is induction-heated. Since it is possible to select which coil of the plurality of resonance coils is made to pass the current depending on the frequency of the electric power input to the heating coil 101, the heating region of the object to be heated 105 can be controlled. For example, when a current is passed through the third resonance coil 203, only the outer peripheral portion of the bottom surface of the article to be heated 105 can be heated.

  As described above, by installing a plurality of self-resonant coils 103 that cause self-resonance at the frequency of the magnetic field generated by the heating coil 101 between the object to be heated 105 and the heating coil 101, the heating region can be controlled by the frequency, and the cost is low. An induction heating device can be realized.

  The induction heating device of the present invention is not limited to the induction heating device used in general homes, restaurants, factories, etc., but can be applied to any device using the principle of electromagnetic induction such as a wireless tag and a non-contact charging device. .

101 Heating coil 102 Inverter circuit 103 Self-resonant coil 104 Top plate 105 Object to be heated 201 First resonance coil 202 Second resonance coil 203 Third resonance coil 204 First resonance capacitor 205 Second resonance capacitor 206 Third Resonance capacitor

Claims (2)

An inverter circuit that generates and outputs high-frequency power of a predetermined frequency;
A heating coil that generates a magnetic field of a predetermined frequency by the high-frequency power supplied from the inverter circuit and induction-heats an object to be heated;
A self-resonant coil installed between the object to be heated and the heating coil;
The self-resonant coil is constituted by a resonance coil and a resonance capacitor, and is an induction heating device that self-resonates at a frequency of a magnetic field generated by the heating coil. The self-resonant coil is composed of a plurality of self-resonant coils each having a different resonance frequency. By controlling the frequency of the high-frequency power output from the inverter circuit, the frequency of the magnetic field generated by the heating coil is changed, and the heating region is changed. The induction heating device according to claim 1 to be controlled.