JP3116800B2 - Induction heating cooker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction heating cooker used in ordinary households and restaurants.

[0002]

2. Description of the Related Art The structure and operation of a conventional induction heating cooker will be described with reference to FIGS. FIG. 7 shows an example of a circuit configuration of a conventional induction heating cooker. Reference numeral 72 denotes a heating coil, on which an object to be heated (a pan or the like) is placed, although not particularly shown in the figure. 73 is a resonance capacitor, 74 is a switching element, in this example, a large current and high withstand voltage IGBT
You are using 75 is a reverse conducting diode connected in parallel to the switching element, and 76 is a control circuit for driving the switching element 74. 72, 73, 7
4 and 75 constitute an inverter circuit. 77 is a smoothing capacitor, 78 is a rectifier diode bridge, and constitutes a DC power converter. 79 is a commercial power supply. Reference numeral 80 denotes a noise prevention capacitor for reducing noise leaking from the device.

FIG. 8 is a diagram showing the arrangement of the conventional induction heating cooker. Reference numeral 81 denotes a heating coil, on which an object to be heated (a pan or the like) is placed, although not particularly shown in the figure. 82 is a resonance capacitor, and 83 is a smoothing capacitor. Reference numeral 84 denotes a radiator plate provided with the switching element 74 of FIG. 7, the reverse conducting diode 75, and the rectifier diode bridge. Reference numeral 85 denotes a magnetic connection plug for supplying commercial power, which has a magnet between commercial power electrodes. Reference numeral 86 denotes a connector for connecting the magnetic connection plug 85. A magnetic plate is provided at a position corresponding to a magnet provided in the magnetic connection plug 85, and supplies a commercial power supply to the inside of the device. Reference numeral 87 denotes a commercial power distribution line that connects the connector 86 to the inside of the device. 88 is a noise prevention capacitor.

FIG. 9 shows operation waveforms of various parts of the inverter during a normal operation. (A) is a drive signal output from the control circuit 76. When this output is high, the switching element 7 is output.
4 turns on. (B) is a current Ic flowing through the switching element 74 and the reverse conducting diode 75, and (C) is a voltage Vce applied across the switching element 84.

The operation of the conventional induction heating cooker will be described below with reference to FIGS. 7 and 9. After turning on the switching element 74 for a predetermined time, the control circuit 76 turns off and resonates the load circuit including the heating coil 72 and the resonance capacitor 73. Further, the control circuit 76 detects Vce, and turns on the switching element 74 again when the fall of Vce becomes lower than a predetermined value. Since the above operation is repeated, in FIG. 9, in response to the drive signal (A) of the control circuit 76, Ic has a high-frequency switching waveform as shown in FIG. Power is supplied to the pot placed in the pan.

As described above, while the conventional induction heating cooker operates, a high-frequency current path for generating a high-frequency switching waveform is formed by the components constituting the inverter circuit and its wiring, thereby generating a high-frequency magnetic field. Let it. In the conventional induction heating cooker, since the connecting device 86 and the commercial power distribution line 87 are arranged away from the high-frequency current path or the heating coil as shown in FIG. 8, the high-frequency magnetic field is induced in the connecting device. As shown in FIG. 8, a noise prevention capacitor 88 is connected to the commercial power supply potential of the printed wiring board inside the device in order to prevent the noise generated inside the device from leaking out of the device. I was

[0007]

However, in the above-described conventional induction heating cooker, a connecting device and a commercial power distribution line connecting the connecting device and the inside of the device are separated from the high-frequency current path and the heating coil by a fixed distance. In the case of miniaturization of equipment, the component arrangement is increased in density, the connector or the commercial power distribution line is close to the high-frequency current path, and the high-frequency current generated from the high-frequency current path is high. Since the magnetic field induces high-frequency noise in the connector and the commercial power distribution line, high-frequency noise leaking from the device via the connector becomes a high level, and there is a limit to miniaturization of the device. Had.

The present invention solves such a conventional problem,
An object of the present invention is to provide a small and inexpensive induction heating cooker.

[0009]

According to the present invention, an inverter circuit having a heating coil, a switching element and a resonance capacitor is connected to a detachable connection plug for supplying commercial power. In an induction heating cooker having a connector and a noise prevention capacitor disposed near the connector and connected between a commercial power supply, switching in which a high-frequency switching waveform generated by on / off operation of the switching element is generated. A loop in which a high-frequency magnetic field generated from a high-frequency current path including an element and a resonance capacitor cancels a high-frequency induced current induced in the noise prevention capacitor is formed in the current path of the noise prevention capacitor.

[0010]

According to the first aspect of the present invention, since the noise prevention capacitor is provided near the connector provided on the outer periphery of the device, the noise prevention capacitor goes out of the device from the portion where the noise prevention capacitor is connected. The length of the commercial power line inside the equipment can be shortened, and the equipment is guided to the distribution line from the part where the noise prevention capacitor is connected to the outlet of the equipment, High frequency noise leaking to the outside can be suppressed.

[0011] In addition, since there is a high possibility that the user can touch the device or the dust or liquid adheres to the connector on the device side corresponding to the detachable connection plug, it is necessary to increase the distance between the electrodes of the commercial power supply potential. Yes, a relatively large opening is formed by the electrode portion and the connection line. If a high-frequency magnetic field is linked to this opening, high-frequency noise is likely to be induced, but since a noise prevention capacitor is connected near this connection, the induced high-frequency noise is bypassed and passed through the commercial power line. As a result, high-frequency noise leaking to the outside of the device can be effectively reduced.

In addition, since a noise preventing capacitor is attached to a connector normally fixed to the outer periphery of the device, it can be stored in an extra space around the connector, and is conventionally mounted and fixed on the bottom surface of the main body. This makes it possible to remove the noise-prevention capacitor from the printed wiring board or the like, which makes it possible to realize a high-density and small-sized component arrangement. In addition, a high-frequency switching waveform generated by the on / off operation of the switching element generates a high-frequency magnetic field generated from a high-frequency current path including a switching element and a resonance capacitor. Since it is formed by the current path of the prevention capacitor,
The high-frequency magnetic field induces an induced high-frequency current in a direction opposite to the high-frequency induced current, and the high-frequency induced current on the same path is canceled. Since the magnitude of the high-frequency induction current generated in the loop is determined by the amount of the high-frequency magnetic field interlinked in the loop, the high-frequency induction current induced in the loop is adjusted by adjusting the area surrounded by the loop. The high-frequency magnetic field can be made to have the same level as the high-frequency current induced by the noise prevention capacitor, and the high-frequency magnetic field has an effect of drastically reducing high-frequency noise induced between the commercial power supplies. Due to the action, it is not necessary to add a component for reducing the high-frequency induction current induced in the noise preventing capacitor by the high-frequency magnetic field, so that the number of components can be reduced and an inexpensive induction heating cooker is provided. be able to. Further, since the loop operates as described above even when the connecting device and the noise prevention capacitor are brought close to the high-frequency current path, high-frequency noise leaking to the outside via the commercial power supply line is reduced to a low level. It is possible to realize high density and small size of component arrangement.

According to a second aspect of the present invention, since the connector is provided with a printed wiring board, the printed wiring board is fixed to the connector with screws or the like, and the printed wiring board is connected to the commercial power supply potential of the connector. Connect the commercial power distribution line to the inside of the equipment and connect the noise suppression capacitor between the commercial power supply of the printed wiring board by soldering, so that the connection of each part is easy, and the assembly and mounting work is simplified. . Further, a loop for canceling a high-frequency induction current induced by the high-frequency magnetic field generated from the high-frequency current path to the noise prevention capacitor,
2. The arrangement of the noise prevention capacitor and the wiring are fixed because it is formed by the current path of the noise prevention capacitor on the printed wiring board, and the high frequency magnetic field generated from the high frequency current path as in the first embodiment is used for noise prevention. The action of the loop for canceling the high frequency induction current induced in the capacitor is stabilized. Therefore, even if a large number of devices are manufactured, the device has a function of stabilizing high-frequency noise leaked to the outside via a commercial power supply at a low level.

According to a third aspect of the present invention, a high-frequency current path including a switching element and a resonance capacitor, which generate a high-frequency switching waveform generated by the on / off operation of the switching element, and a connecting device and the noise preventing capacitor. Since a conductive plate or a conductive film having a substantially planar predetermined area is interposed, a high-frequency wave generated from a high-frequency current path linked to the connector and the noise prevention capacitor in accordance with the predetermined area size. The amount of the magnetic field can be suppressed (the effect of suppressing the magnetic field does not increase even if it is too large). The connector on the device side corresponding to the detachable connection plug as described above has to form a relatively large opening by the electrode portion and the connection line, and it is easy to induce high frequency noise when the magnetic field is linked. In addition, the noise prevention capacitor induces an induced current when a magnetic field interlinks in an area facing the high-frequency current path, but the high-frequency current path and the connector are connected by the action of the conductive plate or the conductive film. Even if they are close to each other, the high-frequency noise level induced by the connector increases, and the high-frequency noise level leaking to the outside via the commercial power line does not increase. Such a component and the connector can be brought close to each other, that is, the component can be mounted at high density to reduce the size.

According to the fourth aspect of the present invention, a printed wiring board composed of a conductive layer and an electric insulating layer can constitute a conductive plate interposed between a connector and a noise prevention capacitor. Part of the printed wiring board
Since the printed wiring board can be used without waste and the production of the conductive plate can be performed simultaneously with the design of the wiring, the function of the conductive plate can be realized at low cost.

According to the fifth aspect of the present invention, the conductive film interposed between the connector and the noise prevention capacitor can be constituted by the conductive film having adhesiveness. However, since it is sticky, it can be fixed securely. Further, since the conductive film is thin, it can be easily processed, and has an effect that it can be installed even in a narrow installation space.

[0017]

Embodiment 1 FIG. 1 is an enlarged view around a connector of an induction heating cooker. Reference numeral 11 denotes a magnetic connection plug for supplying commercial power to the device, and a magnet is provided between the commercial power electrodes. Reference numeral 12 denotes a connector for connecting the magnetic connection plug 11, which is provided with a commercial power supply electrode corresponding to a commercial power supply electrode of the magnetic connection plug and a magnetic plate corresponding to a magnet. However, the means for connecting the magnetic connection plug 11 and the connector 12 is not limited to this. Reference numeral 13 denotes a power terminal of the connector, which is soldered to the commercial power distribution line 14; however, the connecting means is not limited to this. Although not particularly shown in FIG. 1, the commercial power supply line 14 is connected to a commercial power supply potential inside the device. Reference numeral 15 denotes a noise prevention capacitor that suppresses noise leaking from the inside of the device and reduces the length of the distribution line between the commercial power supply electrode of the connector and the connection portion of the noise prevention capacitor. Prevent high-frequency noise induced by a high-frequency magnetic field generated from a heating coil or a high-frequency current path on an electric wire, for example, by bringing a resonance capacitor or a smoothing capacitor forming a high-frequency current path as shown in FIG.
It enables high-density arrangement of component parts of equipment.

In this embodiment, the terminals of the noise preventing capacitor are soldered to the power terminal 13.
The connection means is not limited to this. Further, in this example, the noise prevention capacitor 15 is arranged as shown in FIG. 1, but it is also possible to lengthen the connection part and arrange it at another place of the connector 11.

Embodiment 2 Embodiment 2 of the present invention will be described with reference to FIG. FIG.
Shows the arrangement of the induction heating cooker. 21
Is a magnetic connecting plug, 22 is a connector, 23 is a commercial power distribution line, and the connecting means is the same as that of the first embodiment. 24 is a noise prevention capacitor, 25 is a heating coil, 26 is a resonance capacitor, 27 is a smoothing capacitor, 2
Numeral 8 denotes a heat sink, which is not shown in FIG. 2, but is provided with a switching element, a reverse conducting diode, and a rectifying diode bridge of FIG. 7, and an inverter operation of the switching element, the reverse conducting diode, and the rectifying diode bridge. The heat generated by the heat is radiated.

The high-frequency current paths generated by the on / off operation of the switching elements are 25, 26, 27, and 28.
And generates a high-frequency magnetic field in the direction of arrow 29.
In this example, an aluminum plate 30 is disposed as a conductive plate between the connector 22 and the high-frequency current path, and the amount of a high-frequency magnetic field indicated by an arrow 29 that induces high-frequency noise in the connector 22 is reduced. In this way, it is possible to arrange the components constituting the device at a high density. Here, the area of the aluminum plate 30 is approximately equal to the projected area of the portion where the connector 22 faces the high-frequency current path. Although the aluminum plate 30 is fixed on the housing of the induction heating cooker, the material of the conductor is not limited to this, and the fixing means is not limited.

Embodiment 3 Embodiment 3 of the present invention will be described with reference to FIG. FIG.
Is an enlarged view of the periphery of the connector of the induction heating cooker according to the third aspect. 31 is a magnetic connection plug, 32 is a connector, and the connection means is the same as that of the first embodiment. 33 is a printed wiring board, 34 is a commercial power distribution line, and 35 is a noise prevention capacitor. The power supply terminal of the connector 31, the terminal of the commercial power distribution line 34, and the noise preventing capacitor 35
Are installed in insertion holes provided in the printed wiring board 33, and are connected by soldering.

The printed wiring board 33 allows the connecting device 3
2, the length of the distribution line connecting the commercial power supply electrode and the terminal connection portion of the noise prevention capacitor becomes constant, and the high-frequency magnetic field due to the shape of the distribution line reduces variations in high-frequency noise induced in the distribution line, In addition, since the length is short, high-frequency noise leaking to the outside of the device is stabilized at a low level, and for example, as shown in FIG. ing.

Fourth Embodiment A fourth embodiment of the present invention will be described with reference to FIG. FIG.
Is an enlarged view of the periphery of the connector of the induction heating cooker according to the fourth embodiment. 41 is a magnetic connection plug, 42 is a connector, and the connection means is the same as that of the first embodiment. 43 is a commercial power distribution line, and 44 is a noise prevention capacitor. The noise prevention capacitor 44 has a longer terminal portion as shown in FIG. 4 and is connected to the commercial power supply potential of the connector 42 so as to form a loop, for example, as shown in FIG.
Connected with solder. In addition, the commercial power distribution line 43
Is connected to the commercial power supply electrode of the connector 42 by metal fittings, for example, as shown in FIG. Arrow 45 indicates the direction of the high-frequency magnetic field generated from the high-frequency current path, and arrows 46 and 47 indicate the direction of the induced current induced by the high-frequency magnetic field.

Here, the operation will be described with reference to FIG. Although not shown in FIG. 4, it is assumed that the source of the high-frequency magnetic field 45 has a high-frequency current path configured by the inverter circuit. When the inverter circuit operates, for example, a high-frequency magnetic field is generated in the direction of arrow 45, and an induced current is induced in the noise prevention capacitor in the direction of arrow 46. The high frequency magnetic field further induces an induced current in the direction of arrow 47 in the loop wiring portion. Therefore, arrows 46 and 47
Are canceled out, and noise due to the induced current is reduced. The loop for canceling the induced current induced by the high-frequency magnetic field in the noise prevention capacitor 44 is not limited to the shape shown in FIG.

Accordingly, since high-frequency noise caused by the high-frequency magnetic field can be effectively reduced, components forming the high-frequency current path can be brought close to the connector 42 and the noise prevention capacitor 44 as shown in FIG. And the density of the device can be increased.

Embodiment 5 Embodiment 5 of the present invention will be described with reference to FIG. FIG.
Is an enlarged view around the connector of the induction heating cooker according to the fifth aspect. Reference numeral 51 denotes a magnetic connection plug, and reference numeral 52 denotes a connector. The connection means is the same as that of the first embodiment. 53 is a commercial power distribution line, 54 is a noise prevention capacitor, 55
Is a printed wiring board. Reference numeral 56 denotes a direction of a high-frequency magnetic field. The high-frequency magnetic field is generated from a high-frequency current path in which a high-frequency switching waveform is generated by an on / off operation of a switching element included in the inverter circuit. The connector 5
The second commercial power supply electrode, the terminal of the commercial power distribution line 53, and the terminal of the noise prevention capacitor 54 are installed in insertion holes provided in the printed wiring board 55, and are connected by solder. The printed wiring board 55 has
A distribution line is printed in which the shape of the current path of the noise prevention capacitor 54 is a loop that cancels out the induced current induced in the noise prevention capacitor 54 by the high-frequency magnetic field. Arrow 57 indicates the direction of the induced current induced by the high frequency magnetic field in the noise prevention capacitor, and arrow 58 indicates the direction of the induced current induced by the high frequency magnetic field in the loop.

Here, the operation will be described with reference to FIG. When the induction heating cooker is operated, for example, the high-frequency magnetic field is generated in the direction of arrow 56, and induces the induction current of arrow 57 in the noise prevention capacitor and the induction current of arrow 58 in the loop by the right-hand rule. I do. Therefore, high frequency noise due to the high frequency magnetic field is reduced. In addition, since the loop is formed by a distribution wire of a printed wiring board, the operation can be stabilized even in mass production by a machine, and high density and miniaturization of component parts of a device can be realized. .

Embodiment 6 Embodiment 6 of the present invention will be described with reference to FIG. FIG.
Is an enlarged view around the connector of the induction heating cooker according to claim 6. 61 is a magnetic connection plug, 62 is a connector, the connection means of which is the same as that of the first embodiment. 63
Is a printed wiring board, 64 is a commercial power distribution line, 65 is a noise prevention capacitor, and 66 is an aluminum plate, but may be made of another material. The aluminum plate 66 is fixed to the housing of the induction heating cooker, but the means is not limited. 6 is a heating coil, and 68 is a radiator plate, which is not shown in FIG. 6, but is provided with the switching element, reverse conducting diode, and rectifier diode bridge of FIG. 69 is a resonance capacitor, 70 is a smoothing capacitor, 67, 68,
At 69 and 70, a high-frequency current path in which a high-frequency switching waveform is generated by the on / off operation of the switching element is formed. The arrow 71 indicates the direction of the high-frequency magnetic field generated from the high-frequency current path. Since the aluminum plate is provided in the direction of the high-frequency magnetic field, and the connecting device 62 provided with the noise preventing capacitor 65 is disposed on the other side thereof, high-frequency noise is applied to the noise preventing capacitor 65 and the connecting device 62. The amount of the induced high frequency magnetic field is reduced. Here, the area of the aluminum plate 66 is approximately equal to the projected area of the portion where the connector 22 faces the high-frequency current path, but may be adjusted according to the level of high-frequency noise leaking outside the device. However, even if the area is increased, the effect does not necessarily increase in proportion to the area.

Therefore, by the above-described action of the aluminum plate 66, it is possible to increase the density of the components of the device, and to realize the miniaturization of the device.

The aluminum board 66 can be the same printed wiring board as the printed wiring board used inside the device. Here, the conductor of the printed wiring board is made of a copper film, but its size and operation are the same as those of the aluminum plate 66. Therefore, when the wiring inside the device is designed and mounted on the machine, it can be created at the same time, and the density of the components of the device can be increased inexpensively, that is, the size of the device can be reduced.

Further, the aluminum plate 66 may be made of an aluminum seal having one surface having adhesiveness. The size and operation are the same as those of the aluminum plate. The aluminum seal is thin and can be easily formed into a shape, and since one side has adhesiveness, the work of fixing the aluminum seal to the housing of the induction heating cooker becomes easy. In this example, the installation portion is flat, but installation is possible even in a non-planar state, and the aluminum seal can be installed at an appropriate position. Therefore, it is possible to realize high density of component parts of the device, that is, downsizing of the device.

[0032]

According to the first aspect of the present invention, since a noise prevention capacitor is provided near a connector provided outside a device to which a connection plug for supplying commercial power is connected, a commercial power supply is provided. High-frequency noise that can effectively reduce high-frequency noise leaking to the outside of the device via a power supply line, and includes a switching element and a resonance capacitor that generates a high-frequency switching waveform generated by the on / off operation of the switching element Since a loop for canceling the high-frequency induction current induced in the noise prevention capacitor by the high-frequency magnetic field generated from the path is formed in the current path of the noise prevention capacitor, in particular, the high-frequency current path including the resonance capacitor and the noise prevention capacitor are used. When they are brought close,
The high-frequency noise induced by the high-frequency magnetic field between the commercial power supplies is drastically reduced, the high-frequency noise leaking to the outside via the commercial power supply line can be suppressed to a low level, and a high-density component arrangement and a compact device can be realized. Things.

According to the configuration of the second aspect of the present invention, since the printed circuit board is attached to the connector, the printed circuit board is fixed to the connector with screws or the like, or the printed circuit board is commercialized by the printed circuit board. The power supply terminal, the noise prevention capacitor, and the input terminal on the equipment side can be connected by soldering between the commercial power supply of the printed wiring board, thereby simplifying the connection work and reducing positional variations. By providing a loop that cancels the high-frequency induction current induced in the noise prevention capacitor by the high-frequency magnetic field generated from the high-frequency current path, the noise level between commercial power supplies can be significantly reduced, and the effect may vary depending on the positional relationship between components and wiring Also, as described above, the loop for canceling the high-frequency induced current induced by the high-frequency magnetic field generated from the high-frequency current path in the noise prevention capacitor is formed in the current path of the noise prevention capacitor on the printed wiring board to a minimum. It is possible to stably maintain the noise reduction effect, stabilize high-frequency noise that leaks to the outside via a commercial power line at a low level even when mass-produced, and increase the density of parts. Therefore, it is possible to realize a small and inexpensive induction heating cooker by realizing the miniaturization and the miniaturization of the equipment.

According to the third aspect of the present invention, a high-frequency current path including a switching element and a resonance capacitor that generates a high-frequency switching waveform generated by the on / off operation of the switching element, and a connection between the connector and the noise preventing capacitor. Since a conductive plate or a conductive film having a substantially planar predetermined area is interposed between the connector and the noise-preventing capacitor, a high-frequency current path is generated corresponding to the predetermined area. The amount of the high-frequency magnetic field can be suppressed.

According to the fourth aspect of the present invention, since the conductive plate can be constituted by a printed wiring board composed of a substantially planar conductive layer and an electrically insulating layer, an inexpensive and small induction heating cooker can be realized. It is.

According to the fifth aspect of the present invention, since the conductive film can be constituted by a substantially planar conductive film having tackiness,
A small induction heating cooker can be realized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram around a connector of an induction heating cooker according to an embodiment of the present invention;

FIG. 2 is a configuration diagram of an induction heating cooker according to an embodiment of claim 2;

FIG. 3 is a configuration diagram around a connector of the induction heating cooker according to the third embodiment.

FIG. 4 is a configuration diagram around a connector of the induction heating cooker according to the fourth embodiment.

FIG. 5 is a configuration diagram around a connector of the induction heating cooker according to the fifth embodiment.

FIG. 6 is a configuration diagram of an induction heating cooker according to an embodiment of claims 6, 7, and 8;

FIG. 7 is a circuit configuration diagram of a conventional induction heating cooker.

FIG. 8 is a circuit component layout diagram of a conventional induction heating cooker.

FIG. 9 is an operation waveform diagram of a conventional induction heating cooker.

[Explanation of symbols]

11, 21, 31, 41, 51, 61, 85 Magnetic connection plug 12, 22, 32, 42, 52, 62, 86 Connector 13 Connector power supply terminal 14, 23, 34, 43, 53, 64, 87 Commercial Power distribution line 15, 24, 35, 44, 54, 65, 80, 88 Noise prevention capacitor 25, 67, 72, 81 Heating coil 26, 69, 73, 82 Resonant capacitor 27, 70, 77, 83 Smoothing capacitor 28 , 68, 84 Radiator plate 29, 45, 56, 71 Direction of high-frequency magnetic field 30 Aluminum plate 33, 55, 63 Printed wiring board 46, 47, 57, 58 Direction of induced current 66 Printed wiring board, aluminum plate, aluminum seal 74 Switching element 75 Reverse conducting diode 76 Control circuit 78 Rectifier diode bridge 79 Commercial power supply

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Daizo Ogata 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-59-138096 (JP, A) −41178 (JP, Y2) Jikken Sho 61-34754 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05B 6/12

Claims (5)

(57) [Claims] An inverter circuit including a heating coil, a switching element, and a resonance capacitor; a connector for connecting a detachable connection plug for supplying commercial power;
A high-frequency current path including a noise-prevention capacitor disposed near the connector and connected between commercial power supplies, and a switching element generating a high-frequency switching waveform generated by on / off operation of the switching element; and a resonance capacitor An induction heating cooker in which a loop for canceling a high-frequency induction current induced by a high-frequency magnetic field generated in a noise-prevention capacitor by a current path of the noise-prevention capacitor. And a loop for canceling a high-frequency induction current induced by the high-frequency magnetic field generated from the high-frequency current path in the noise-preventing capacitor. 2. The induction heating cooker according to claim 1, wherein the induction heating cooker is formed by a current path. Wherein the the high-frequency current path, connectors and induction heating according to claim 1 or claim 2, wherein interposing the generally planar conductive plate or a conductive film having a predetermined area between said noise preventing capacitor Cooking device. 4. An inverter circuit comprising a heating coil, a switching element, and a resonance capacitor, and a connector for connecting a detachable connection plug for supplying commercial power, wherein the connector is generated by an on / off operation of the switching element. Induction heating cooker in which a high-frequency current path including a switching element generating a high-frequency switching waveform and a resonance capacitor, and a printed wiring board having a predetermined area and including a conductive layer and an electrical insulating layer are interposed between the connectors. . 5. An inverter circuit comprising a heating coil, a switching element, and a resonance capacitor, and a connector for connecting a detachable connection plug for supplying commercial power, wherein the connector is generated by an on / off operation of the switching element. An induction heating cooker in which a high-frequency current path including a switching element generating a high-frequency switching waveform and a resonance capacitor, and a conductive film having a predetermined area and having adhesiveness are interposed between the connectors.