JP2020095781A - Induction heating cooker - Google Patents

Abstract

To suppress leakage of a radiation noise generated from an induction heating coil to an outside part via a power supply cord.SOLUTION: An induction heating cooker 10 comprises: a casing 11 having, on its upper face, a top plate 12 on which a cooking container is placed; an induction heating coil 20 which is disposed, in an upper portion inside the casing 11, under the top plate 12; a main substrate 21 having a high-frequency current supply circuit 22 which is disposed, in a lower portion inside the casing 11, under the induction heating coil 20; a power supply cord 23 inserted through a rear wall of the casing 11; and a noise filter 24 disposed, in the lower portion inside the casing 11, at a back side of the main substrate 21. Inside the casing 11, an aluminum shield plate 27 for preventing the propagation of a radiation noise generated from the induction heating coil 20 is provided above the noise filter 24 and the power supply cord 23.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to an induction heating cooker that heats and cooks foodstuffs by generating heat by Joule heat generated by electric resistance when an eddy current flows in a cooking container such as a pot placed above a top plate.

The following Patent Document 1 discloses an induction heating cooker installed on a counter in a kitchen. The induction heating cooker has a casing having a top plate on which a cooking container such as a pot is placed, and an induction magnetic field for heating the cooking container, which is arranged in the upper part of the casing and below the top plate. A induction heating coil, a main board having a high-frequency current supply circuit arranged below the induction heating coil in the lower part of the casing to supply a high-frequency current to the induction heating coil, and a rear wall of the casing. A power cord that is inserted into the main board to supply power to the main board, and a noise filter that is disposed in the lower part of the casing on the rear side of the main board and removes noise between the power cord and the main board. There is.

In this induction heating cooker, when a cooking container such as a pot is placed on the upper side of the top plate and a high frequency current is supplied to the induction heating coil by the inverter circuit, an induction magnetic field is generated on the upper side of the top plate, The cooking container such as a pot placed on the upper side of the table heats up due to Joule heat generated by electric resistance when an eddy current flows, and the food material placed in the cooking container such as a pot is cooked in the heating container.

JP, 2017-208259, A

In the induction heating cooker described in Patent Document 1 described above, a noise filter that removes noise between the power cord and the main board is provided in the lower portion of the casing, and this noise filter is connected to the power cord from an external power source. The noise included in the electric power supplied by the inverter circuit and the noise terminal voltage generated from the inverter circuit are reduced. Although this noise filter can reduce the noise terminal voltage transmitted from the inverter circuit to the electric wiring, the radiation noise radiated from the induction heating coil may propagate to the noise filter or the power cord and leak to the outside. An object of the present invention is to prevent radiation noise generated from an induction heating coil from leaking to the outside through a power cord.

In order to solve the above problems, the present invention provides a casing having a top plate on which a cooking container is placed on an upper surface, and an upper part of the casing that is disposed below the top plate to heat the cooking container. An induction heating coil for generating an induction magnetic field, a main board having a high-frequency current supply circuit disposed below the induction heating coil in the lower part of the casing and supplying a high-frequency current to the induction heating coil, and the casing. A power cord that is inserted through the rear wall and supplies power to the main board from an external power source, and is disposed on the rear side of the main board in the lower part of the casing to remove noise between the power cord and the main board. An induction heating cooker including a noise filter, wherein an aluminum shielding plate is provided in the casing above the noise filter and the power cord to prevent propagation of radiation noise generated from the induction heating coil. A characteristic induction heating cooker is provided.

In the induction heating cooker configured as described above, the noise filter and the aluminum shielding plate that prevents the radiation noise generated from the induction heating coil from propagating above the power cord are provided in the casing. Radiation noise generated from the heating coil can be prevented from propagating to the noise filter and the power cord by the shield plate, and the radiation noise can be prevented from leaking outside through the power cord.

In the induction heating cooker configured as described above, it is preferable that the front edge of the shield plate is provided with a front edge shield portion extending downward at the left-right position where the power cord is arranged. In this case, the radiation noise obliquely incident on the lower side of the shield plate from the induction heating coil was shielded by the front edge shield portion and could be prevented from propagating to the power cord.

In the induction heating cooker configured as described above, the shielding plate is arranged so as to be inclined so that one side in the horizontal direction is the lower side, and the side wall portion rising to the upper side is provided at the edge except one side of the shielding plate. It is preferably provided. In this case, when water flows in from the upper part of the casing, the shielding plate can receive the water and flow it in one of the horizontal directions, and the water does not flow in only one of the horizontal directions in the casing. I was able to do so.

It is a perspective view of the induction heating cooker of this invention. It is a perspective view which removed the top plate and front wall of an induction heating cooker. It is a perspective view which removed the induction heating coil and the 1st and 2nd air guides from FIG. It is an exploded perspective view which removed an induction heating coil, a main board, a noise filter board, etc. from a mounting member. It is a disassembled perspective view corresponding to FIG. 4 of embodiment which changed the shield plate.

Hereinafter, an embodiment of an induction heating cooker of the present invention will be described with reference to the accompanying drawings. As shown in FIGS. 1 to 3, the induction heating cooker 10 of this embodiment is installed in a counter of a kitchen or the like, and when the induction heating coil 20 is supplied with a high frequency current from the inverter circuit 22, An induction magnetic field is generated on the upper side, and the cooking container such as a pan is heated by Joule heat generated by electric resistance when an eddy current flows through the cooking container such as a pan placed on the upper side of the top plate 12, and the heating container is heated. The food put in is cooked by heating. The induction heating cooker 10 has a casing 11 having a top plate 12 on which a cooking container such as a pot is placed, and a heating plate which is disposed below the top plate 12 in the casing 11 to heat the cooking container. A main board 21 having an induction heating coil 20 for generating an induction magnetic field, an inverter circuit (high frequency current supply circuit) 22 arranged below the casing 11 for supplying a high frequency current to the induction heating coil 20, and the casing 11 A power cord 23 that is inserted through the rear wall to supply power to the main board 21 from an external power source, and a power cord 23 that is disposed in the lower part of the casing 11 at the rear side of the main board 21 and that connects the power cord 23 and the main board 21. And a noise filter 24 that removes noise in between.

As shown in FIGS. 1 and 2, the casing 11 including the top plate 12 has a substantially rectangular parallelepiped shape. As shown in FIG. 2, a substantially U-shaped mounting member 13 that opens rearward when viewed from above is provided inside the casing 11 so as to be closer to the rear side, and the mounting member 13 includes an induction heating coil. Twenty is attached. The induction heating coil 20 causes an eddy current to flow in a cooking container such as a pot placed on the upper surface of the top plate 12 under the influence of an induction magnetic field generated when a high frequency current is supplied, and the eddy current is generated in the cooking container. The heat is generated by the Joule heat generated by the electric resistance when flowing.

As shown in FIGS. 3 and 4, a main board 21 having an inverter circuit (high frequency current supply circuit) 22 for supplying a high frequency current to the induction heating coil 20 is provided in the lower portion of the casing 11. The inverter circuit 22 includes a large capacitor and a switching element to generate a high frequency current, and the inverter circuit 22 generates a large amount of heat from the large capacitor and the switching element when generating a high frequency current. A power cord 23 is connected to the main substrate 21 via a noise filter substrate 24. The power cord 23 penetrates the lower right portion of the rear wall of the casing 11 and is led out to the outside to be connected to an external power source. The inverter circuit 22 of the main board 21 supplies a high frequency current to the induction heating coil 20 by the power supplied from the external power supply by the power cord 23.

As shown in FIGS. 3 and 4, a noise filter substrate (noise filter) 24 is provided in the lower portion of the casing 11 at the rear side of the main substrate 21. The noise filter board 24 reduces noise propagating through the power cord 23 from an external commercial power source and noise terminal voltage (noise) generated from the inverter circuit 22 of the main board 21 and propagating through electric wiring.

As shown in FIGS. 2 to 4, the cooling fan 25 (25, 25b) is provided on the front wall of the mounting member 13 in the vertical direction. The upper cooling fan 25a cools the induction heating coil 20, and the lower cooling fan 25b cools the inverter circuit 22 of the main board 21. As shown in FIG. 4, on the front wall of the mounting member 13, a first air guide guide 26a made of resin is provided on the rear side of the upper cooling fan 25a. The first air guide 26a has a substantially box shape with the upper side and the front side opened, and guides the air blown by the upper cooling fan 25a toward the center of the induction heating coil 20. The main board 21 is provided with a second air guide 26b made of resin behind the lower cooling fan 25b. The second air guide 26b has a substantially U-shaped vertical cross-section along the left-right direction, extends forward and backward above the heat radiation fins of the inverter circuit 22, and is blown by the cooling fan 25b on the lower side. Through the heat radiation fins of the inverter circuit 22.

As shown in FIGS. 2 to 4, an aluminum shielding plate 27 is provided below the induction heating coil 20 inside the casing 11 and above the noise filter substrate 24 and the power cord 23. Has a function of preventing radiation noise generated from the induction heating coil 20 from propagating to the noise filter substrate 24 and the power cord 23. The shield plate 27 extends from an intermediate portion in the front-rear direction of the casing 11 to the rear edge, and is attached in a state of being in close contact with the rear wall of the casing 11 and the left and right side walls of the mounting member 13. A front edge shield portion 27a extending downward is provided on the right side portion of the front edge of the shield plate 27. The front edge shield portion 27a is provided at the same position as the position where the power cord 23 is arranged in the left-right direction, and the radiation noise generated from the induction heating coil 20 propagates to the power cord 23 below the shield plate 27. This is to prevent it.

The operation of the induction heating cooker 10 configured as above will be described. When a cook puts a cooking container such as a pot containing food on the upper side of the top plate 12 and operates the operation panel 14 provided on the front surface of the casing 11 to start cooking, the inverter circuit 22 receives external data. The electric power is supplied from the power supply 23 by the power cord 23, and the induction heating coil 20 is supplied with the high frequency current from the inverter circuit 22. An induction magnetic field is generated on the upper side of the top plate 12 when a high-frequency current is supplied to the induction heating coil 20, and a cooking container such as a pot placed on the upper side of the top plate 12 is caused by electric resistance when an eddy current flows. Heat is generated by Joule heat, and the food material placed in a cooking container such as a pan is cooked by the heating container.

When a high-frequency current is supplied to the induction heating coil 20, radiation noise may be generated from the induction heating coil 20 in the casing 11, and the radiation noise may propagate to the noise filter substrate 24 and the power cord 23. In the induction heating cooker 10 of this embodiment, the induction heating coil 20 is arranged in the upper part of the casing 11, and the noise filter substrate 24 and the power cord 23 are located in the rear side of the casing 11 below the induction heating coil 20. A shield plate 27 made of aluminum, which is disposed on the lower side, is provided inside the casing 11 above the noise filter substrate 24 and the power cord 23 to prevent the radiation noise generated from the induction heating coil 20 from propagating. Thereby, the radiation noise generated from the induction heating coil 20 can be prevented from propagating to the noise filter substrate 24 and the power cord 23, and the radiation noise can be prevented from leaking to the outside through the power cord 23.

The front edge of the shield plate 27 is provided with a front edge shield portion 27a extending downward at the position where the power cord 23 is arranged in the left-right direction. With this, it is possible to prevent the radiation noise obliquely incident on the lower side of the shield plate 27 from the induction heating coil 20 from propagating to the power cord 23 by the front edge shield portion 27a, and the radiation noise is transmitted via the power cord 23. It was possible to reduce the leakage to the outside. In this embodiment, the power cord 23 is arranged on the right side of the casing 11, and the front edge shield portion 27a is also provided on the right side of the shield plate 27 in the casing 11, but it is not limited to this. When the power cord 23 is disposed on the left side portion of the casing 11, the front edge shield portion 27a is provided on the left side portion of the shield plate 27 in the casing 11, and the power cord 23 is disposed in the center of the casing 11 in the left-right direction. When it is arranged in a portion, the front edge shield portion 27a may be provided in the casing 11 at the center portion of the shield plate 27 in the left-right direction.

In the induction heating cooker 10 configured as described above, the shield plate 27 is arranged on the upper side of the noise filter substrate 24 and the power cord 23 so as to extend rearward of the intermediate portion in the front-rear direction in the casing 11. The present invention is not limited to this, and as shown in FIG. 5, the shield plate 27 may extend from the front portion to the rear edge in the casing 11. In this case, it is preferable to arrange the shielding plate 27 at an intermediate portion in the vertical direction between the upper cooling fan 25a and the lower cooling fan 25b. When the shielding plate 27 is arranged between the upper and lower cooling fans 25a and 25b, the shielding plate 27 can be made to function as the air guide of the main board 21, and the second air guide 26b can be omitted.

Further, the shielding plate 27 also functions as a water receiver when water flows in from the upper part of the casing 11, and can prevent water from splashing on the main substrate 21 and the noise filter substrate 24. In this case, the shield plate 27 is arranged so that the front side is on the lower side as one of the horizontal directions, and side walls that stand up on the left and right side edge portions and the rear edge portion as edge portions excluding one of the shield plate 27. The portion 27b is provided. Thereby, when the water that has flowed in from the upper part of the casing 11 is received by the shielding plate 27, the water received by the shielding plate 27 is received by the side wall portions 27b on the left and right side edges and the rear edge (other than one in the horizontal direction). The water received by the shielding plate 27 can be made to flow only from the front part (one side in the horizontal direction) so that the water does not flow down, and the water surely flows down to the position where the main substrate 21 and the noise filter substrate 24 are not arranged. I was able to do so.

10... Induction heating cooker, 11... Casing, 12... Top plate, 20... Induction heating coil, 21... Main substrate, 22... High frequency current supply circuit (inverter circuit), 23... Power cord, 24... Noise filter (noise filter) Substrate), 27... Shielding plate, 27a... Front edge shielding part, 27b... Side wall part.

Claims (3)

A casing having a top plate on which a cooking container is placed,
An induction heating coil disposed in the upper part of the casing and below the top plate to generate an induction magnetic field for heating the cooking container;
A main board that is disposed below the induction heating coil in the lower part of the casing and has a high-frequency current supply circuit that supplies a high-frequency current to the induction heating coil;
A power cord that is inserted through the rear wall of the casing to supply power to the main board from an external power source,
An induction heating cooker, which is disposed in the lower part of the casing on the rear side of the main board and includes a noise filter for removing noise between the power cord and the main board,
An induction heating cooker, characterized in that, in the casing, an aluminum shielding plate is provided above the noise filter and the power cord to prevent propagation of radiation noise generated from the induction heating coil. The induction heating cooker according to claim 1,
An induction heating cooker, characterized in that a front edge shield part extending downward is provided at a front edge of the shield plate at a position where the power cord is arranged in the left-right direction. The induction heating cooker according to claim 1,
Induction cooking, characterized in that the shielding plate is arranged so as to be inclined so that one side in the horizontal direction is on the lower side, and a side wall portion that rises upward is provided at an edge portion of the shielding plate other than the one side. vessel.

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