JPS637673B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an induction heating cooker used in general households.

Conventional Structure and its Problems The structure of a conventional induction heating cooker generally used for home use is shown in FIG.
This figure shows a single-cooker induction heating cooker with the top plate (pan plate) removed. 1 is the power switch, 2 is the power control unit, 3 is the cooling fan, and 4 is the Heating coil, 5 is the main semiconductor part, 6
7 is a high frequency oscillation capacitor, 7 is a power supply control board, 8 is a high frequency oscillation control board, and 9 is a power supply noise prevention coil.

In the above configuration, the chiyoke coil 9 is made by winding an EI type iron core, and is usually large in shape, high in cost, and heavy in weight. This has become a major impeding factor.

OBJECT OF THE INVENTION The present invention relates to an induction heating cooker that aims to solve these problems.

Composition of the Invention The induction heating cooker of the present invention includes a heating coil that generates a high-frequency magnetic field for inductively heating an object to be heated, a high-frequency oscillation section that supplies a high-frequency current to the heating coil, and a high-frequency oscillation section that is At least an inductor comprising a power supply section that supplies frequency or DC power, a control circuit section that controls the high frequency oscillation section, and a casing section that houses these, and located within the high frequency oscillation section or within the power supply section. One is constructed by winding the heating coil near its outer periphery.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments will be described with reference to the accompanying drawings.

In FIG. 2, 10 is a power switch, 11 is a power control unit, 12 is a cooling fan, 1
3 is a heating coil that generates a high frequency magnetic field for inductively heating an object to be heated; 14 is a main semiconductor section; 15 is a capacitor for high frequency oscillation; 16 is a control board for power supply; 17 is a control board for high frequency oscillation; 18 is the above-mentioned An inductor 19 for preventing power supply noise is constructed by winding a wire near the outer periphery of the heating coil 13. Reference numeral 19 is a housing portion that accommodates the heating coil 13 and the like.

Figure 3 shows the circuit configuration. In the figure, 20 is a full-wave rectifier, and 21 is a power transformer, which are placed on the power supply control board 16. 22 is a control circuit;
It is configured on a high frequency oscillation control board 17.
23 is a power supply capacitor, 24 is a resonance capacitor, which is the high frequency oscillation capacitor 15 in Fig. 2.
It corresponds to

There may be a plurality of inductors 18 for power supply noise prevention, and at least one of them is placed near the outer periphery of the heating coil 13 so that the high frequency component of the magnetic field generated by the inductor and the high frequency magnetic field generated by the heating coil 13 cancel each other out. It is constructed by winding wires to match. That is, the winding direction is opposite to that of the heating coil 13. Furthermore, 25 is a diode, 2
Reference numeral 6 denotes a transistor, which is arranged in the main semiconductor section 14 of FIG.

27 is a top plate placed on the heating coil 13, and 28 is a pot for heating the object.

The high-frequency oscillation unit 2 supplies high-frequency power to the heating coil 13 using the above-mentioned resonance capacitor 24, diode 25, and transistor 26.
9, the inductor 18, the full-wave rectifier 20, and the power supply capacitor 23.
A power supply unit 30 supplies commercial frequency or DC power to the power source 9, and further includes a power transformer 21 and a control circuit 2.
2 constitutes a control circuit section 31 that controls the high frequency oscillation section 29. These high frequency oscillators 2
9, the power supply section 30 and the control circuit section 31 are housed in the housing section 19 together with the heating coil 13.

In the above configuration, when the power switch 10 is turned on, the full-wave rectifier 20 causes the power supply capacitor 23 to
A DC voltage is applied across the

In this state, the control circuit 22 sends the transistor 2
When base current is supplied to 6 at predetermined intervals, heating coil 13, resonance capacitor 24, power supply capacitor 23, diode 25, transistor 26
A high frequency current flows through the heating coil 13 due to the resonance loop of the pan 28 placed on the heating coil 13.
will be heated by induction.

Although the inductor 18 can operate without being inserted, it is indispensable in practice to prevent radio wave interference to the power supply line due to harmonics of the resonant current and voltage mentioned above. It has a value of . In this embodiment, the inductor 18 is constructed by winding a wire near the outer periphery of the heating coil 13, and the winding direction is the magnetic field of the high frequency component generated by the heating coil 13 and the high frequency component flowing through the inductor 18. The windings are designed to combine so that the levels cancel each other out. That is, the outermost layer of the high frequency magnetic flux generated from the heating coil 13 is canceled out by the inductor 18. With this configuration, compared to the conventionally used chi-yoke coil type, the noise reduction effect can be easily achieved by simply winding the heating coil 13 near the outer periphery without worrying about the inductance value. is,
This will greatly contribute to cost reduction.

Effects of the Invention As described above, the induction heating cooker of the present invention does not require a core material, and can form an inductor by simply winding the coil, compared to the case where a conventional chiyoke coil is used. By bringing it closer to the heating coil, the winding length can be reduced.
In terms of shape, it is possible to realize an extremely innovative induction heating cooker that not only makes the cooker thinner as a whole, but also contributes to weight reduction, and further increases the noise reduction effect.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing the arrangement of parts of a conventional induction heating cooker, Fig. 2 is a plan view showing the arrangement of parts of an induction heating cooker according to an embodiment of the present invention, and Fig. 3 is a plan view showing the arrangement of parts of an induction heating cooker according to an embodiment of the present invention. FIG. 13... Heating coil, 18... Inductor, 1
9... Housing section, 29... High frequency oscillation section, 30...
Power supply section, 31... control circuit section.

Claims (1)

[Claims] 1. A heating coil that generates a high-frequency magnetic field for inductively heating an object to be heated, a high-frequency oscillation section that supplies a high-frequency current to the heating coil, and a power supply section that supplies commercial frequency or DC power to the high-frequency oscillation section. , a control circuit unit that controls the high frequency oscillation unit;
The heating coil, the high-frequency oscillation section, the power supply section, and the control circuit section are housed in a housing section, and at least one of the inductors located in the power supply section is wound around the outer periphery of the heating coil. An induction heating cooker constructed by applying wires and arranged in a direction in which the high frequency component of the magnetic field generated by the inductor and the high frequency magnetic field generated by the heating coil cancel each other out.