JPS6245437Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heating cooker, and more particularly to a radio wave leakage prevention structure of a heater penetrating portion that is freely attached and detached through a heating chamber wall.

2. Description of the Related Art There are known heating cookers that have an oven function using a red-hot heater in addition to a microwave oven function.

In such a heating cooker, when the incandescent heater is detachably attached for maintenance and inspection, play is provided between the heater and the heater penetration portion on the heating chamber wall side. As a result, sparks are generated between the heater penetration portion and the heater, and in order to prevent this and to improve the ease of attaching and detaching the heater, an insulating sleeve made of Teflon is placed over the outer periphery of the heater. As a result, metal contact cannot be made between the heater penetrating portion and the heater, resulting in the inconvenience that radio waves inside the heating chamber leak to the outside from the heater penetrating portion.
For this reason, it is known that the heater penetrating portion is provided with a check chamber for absorbing radio waves to prevent radio wave leakage.

Here, the characteristic of the Chiyork chamber structure is that a mode with the same phase exists at every half wavelength, and if there is a place where the electric field is 0 (short circuit), there will be a similar electric field at a distance of half a wavelength. This takes advantage of the fact that 0 occurs. In other words, if the former electric field zero section is constructed as a complete short circuit, a condensed short circuit will inevitably occur at a location half a wavelength away from that point, and by making this condensed short circuit a through-hole of the heater, , it is possible to seal radio waves even if there is a gap in the penetration part. FIG. 1 shows the conventional structure of this type of heating chamber. 1 is a heating chamber, 2 is a back wall of the heating chamber, 3 is a main body case of the heater, 4 is a heater, and 4A
4B is a terminal portion, 5 is an insulator covering the main body portion 4A, and 2a is a heater through hole formed in the back wall 2 of the heating chamber, through which the heater 4 is removably supported. 7 is the Chiyoke room, the details of which will be described later. 8 is an insulating cover that covers the heater terminal portion 4B;
It is coupled to an end face of a chiyoke chamber structure, which will be described later. 9 is a power supply line to the heater 4; 10 is a power supply plug attached to the inner end surface of the insulating cover 8 to receive power from the power supply line 9; The chamber structure 11 constituting the chamber 7 has an outer cylindrical portion 1.
It has an inner and outer double structure of 1B and inner cylinder part 11A,
Inner cylinder portion 1 into which the main body portion 4A of the heater 4 is inserted
It has a configuration in which one end surface of the space between 1A and the outer cylinder part 11B is closed, and there is a space between the inner surface of the closed part 11C and the opening surface of the inner cylinder part 11A, which is located approximately on the same plane as the closed part 11C. It has a configuration in which a three-dimensional circuit of approximately 1/2 wavelength of the wavelength used is formed, and this three-dimensional circuit is formed such that the length of the inner cylindrical portion 11B, which serves as a folding portion of radio waves, is approximately one-quarter wavelength. As a result, point a in the figure becomes a complete short circuit, point b becomes a pseudo short circuit, and this pseudo short circuit b
It is now possible to seal radio waves.

However, in the conventional structure of the heating chamber 7 as described above, the pseudo short circuit part b is formed outside the heating chamber 1, so that the pseudo short circuit part b is connected to the heating chamber back wall 2.
Depending on the distance between the heating chamber 2 and the length of the insulating cover 8, the structure of the lid penetration part is quite long outside the heating chamber 1, and a large space is required between the back wall 2 and the main body case 3. As a result, the external size of the main body case 3 has increased, resulting in a drawback that the heating cooker requires a large installation space. Also, pseudo short circuit b
was located at the outlet of the heater 4, so the radio wave seal was inadequate.

In view of the above-mentioned conventional circumstances, the present invention has been developed by providing a cylindrical three-dimensional circuit with a wavelength of approximately 1/4 of the wavelength used on the heating chamber wall, and also providing a cylindrical three-dimensional circuit on the outer wall of the heating chamber in a plane perpendicular to the axial direction of the cylindrical three-dimensional circuit. A substantially 1/4-wavelength three-dimensional circuit located flat and concentrically is provided in the cylindrical three-dimensional circuit, and a chiyoke chamber for radio wave absorption is formed by both three-dimensional circuits. By arranging the heater to be located inside the heating chamber, the length of the portion of the heating chamber located outside the heating chamber and the power supply part of the heater can be shortened.
The present invention provides a heating cooker that reduces the space occupied by the penetrating part structure on the outer wall of the heating chamber of the penetrating part, miniaturizes the main body structure, and saves installation space for the penetrating device. By configuring a microwave non-propagation circuit in the antenna, more effective radio wave sealing is achieved.

An embodiment of the present invention will be described below with reference to FIG.

In this figure, the same elements as those in FIG. 1 are given the same reference numerals to simplify the explanation.

In this invention, the abbreviation of the wavelength used is placed on the wall of the heating chamber.
A 1/4 wavelength cylindrical three-dimensional circuit is provided, and an approximately 1/4 wavelength three-dimensional circuit is provided on the outer wall of the heating chamber in a flat and concentric manner in a plane perpendicular to the axial direction of the cylindrical three-dimensional circuit. A radio wave absorption chamber is configured, and the cylindrical three-dimensional circuit on the inner wall of the heating chamber is used as a penetration part of a heating chamber wall penetrating component.

That is, 12 is a cylindrical three-dimensional circuit structure integrally molded on the inner surface of the back wall 2 of the heating chamber to form the cylindrical three-dimensional circuit 13, and serves as a through hole for the heater 4. 15 is the back wall 2 of the heating chamber in order to form the flat three-dimensional circuit 14.
It is a flat three-dimensional circuit structure fixed to the outer surface by screws etc. It consists of a flat cylindrical body with one end closed, the open end serves as the attachment part to the back wall 2, and the closed end has a central part. An insertion hole 15A for the heater 4 is formed.

Here, the length of the cylindrical three-dimensional circuit structure 12 is approximately
The distance between the inner peripheral surface of the flat three-dimensional circuit structure 15 and the central axis of the heater 4 is approximately 1/4 wavelength.
Set to 1/4 wavelength. The three-dimensional circuits 13 and 14 constitute a radio wave absorption chamber. The heater 4 is inserted into the outside of the back wall 2 through the back wall 2 so that its main body 4A is located inside the cylindrical three-dimensional circuit structure 12.

Furthermore, in this configuration, the flat three-dimensional circuit structure 1
A cylindrical insulator 19 made of Teflon or the like is connected to the opening 18A of an annular insulating plate 18 made of Teflon or the like which is in contact with the outer end surface of the structure 15 on the inner periphery of the insertion hole 15A of the structure 15.
The terminal portion 4B of the heater 4 is positioned inside the cylindrical insulator 19, and the power supply plug 10 located inside the cylindrical insulator 19 is located on the outer end surface of the annular insulator 18. A metal active part plate 20 made of stainless steel or the like having a radius of approximately 1/4 wavelength fixed by welding or the like is tightly attached by an insulating cover 17 attached to cover the flat three-dimensional circuit structure 15, A non-propagation circuit is configured between the flat three-dimensional circuit structure 15 and the insulating cover 17.

According to the above configuration, the flat three-dimensional circuit structure 15
Point a on the inner peripheral surface becomes a complete short circuit, and point b at the tip of the cylindrical three-dimensional circuit structure 12 becomes a pseudo short circuit.
Therefore, radio waves can be absorbed by such a chiyoke chamber structure, and the inner peripheral surface of the cylindrical three-dimensional circuit structure 12, which is the penetrating part of the heater 4, and the main body 4 of the heater 4 can be absorbed.
Even if there is a gap between A and the outer peripheral surface, leakage of radio waves can be prevented, and since the pseudo-short circuit part b is located inside the heating chamber 1 to be sealed, the radio wave sealing effect at the heater outlet is high.

According to this configuration, the cylindrical three-dimensional circuit 13 is configured inside the heating chamber 1, and the flat three-dimensional circuit 14 is configured outside the heating chamber 1. The structure of the heater penetrating portion can be shortened in length, and a large space is not required between the back wall 2 and the main body case 3. Further, by configuring the power supply section to the heater 4 within the housing, there is an advantage that the length can be further shortened.

Therefore, the shape of the cooking device main body case 3 can be made smaller, and the installation space of the cooking device can be saved.

Furthermore, with this configuration, the heater power supply section is approximately 1/4
By providing a microwave non-propagating circuit using a metal live part 20 plate with a radius of the wavelength, it is possible to effectively prevent radio waves from slipping through the power supply part, and to enhance the sealing effect. Incidentally, in a conventional radio wave leakage structure using only a simple choke chamber, the amount of leakage radio waves was about 5mw/ ^mm2 , but with this configuration, it is possible to reduce it to 1/10 of that, or 0.5mw/ ^mm2 .

Further, the live metal plate 20 has an effect as a heat sink, and has the advantage of suppressing the temperature rise of the power supply plug 10.

As explained above, according to the present invention, a cylindrical three-dimensional circuit of approximately 1/4 wavelength of the wavelength used is provided inside the heating chamber, and a flat three-dimensional circuit of approximately 1/4 wavelength of the wavelength used is provided outside the heating chamber. By providing a chiyoke chamber for radio wave absorption and locating the power supply part to the heater inside the chiyoke chamber, it is possible to short-circuit the length of the common part structure of the heater located outside the heating chamber, and the main body case around the heating chamber can be short-circuited. The size can be made smaller, which is effective in saving space for installing the cooker, and the provision of a microwave non-propagation circuit in the heater power supply section effectively prevents radio waves from passing through the heater power supply section. This has a great practical effect of further improving the radio wave sealing properties and suppressing the temperature rise of the power supply plug.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the structure of a heater penetrating portion in a conventional cooking device, and FIG. 2 is a sectional view showing the structure of a heater penetrating portion in a cooking device according to the present invention. DESCRIPTION OF SYMBOLS 1... Heating chamber, 2... Back wall, 3... Main body case, 4... Heater, 4B... Terminal, 10... Power supply plug, 12... Cylindrical three-dimensional circuit structure, 13...
Cylindrical three-dimensional circuit, 14... Flat three-dimensional circuit, 15...
Flat three-dimensional circuit structure, 17... Insulation cover, 18
...Annular insulating plate, 19...Cylindrical insulator, 20...
Live power board.

Claims (1)

[Scope of utility model registration request] A cylindrical three-dimensional circuit with a wavelength of approximately 1/4 of the wavelength used is provided on the inner wall of the heating chamber formed in the cooking device main body, which functions as a microwave oven and an oven. Approximately 1/4 wavelength flat three-dimensional circuits are arranged in a flat and concentric manner in a vertical plane, and both three-dimensional circuits form a chiyoke chamber for absorbing radio waves, and the cylindrical three-dimensional circuit on the wall of the heating chamber is attached to the heating chamber wall. A cylindrical insulator is provided as a penetrating portion of the heater that is freely attached and detachably supported, and is engaged with an opening in an annular insulating plate that is in contact with an outer end surface of the flat three-dimensional circuit structure on the inner periphery of the center opening of the flat three-dimensional circuit structure. The terminal portion of the heater is positioned inside the cylindrical insulator, and the power supply plug located inside the cylindrical insulator is fixed to the outer end surface of the annular insulator. a metal live-current part plate having a radius of
A cooking device characterized in that a non-propagation circuit is constructed between the flat three-dimensional circuit structure and the insulating cover.