JPS61151991A - Door seal apparatus for high frequency heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a door seal device for preventing leakage of radio waves from around the door of a high frequency heating device.

Conventional technology In general, high-frequency heating devices such as microwave ovens emit high-frequency electromagnetic waves into a heating chamber and use the heating effect to heat objects to be heated such as food. There is a risk that radio waves may leak through small gaps in the area, causing various problems.

?゛・ In order to prevent this radio wave leakage, conventionally, a metal groove (this is called a choke structure) with a depth of approximately 1/4 wavelength of the radio waves used is installed in the door or the heating chamber wall facing the door. ) was installed to prevent the leakage of radio waves mentioned above.

4 and 5 are a cross-sectional view and a schematic diagram of a microwave oven having the above-mentioned thousand-point structure, in which a part of the radio waves filling the heating chamber 17 of the microwave oven is and door 2
attempts to leak to the outside through the gap between the

FIG. 6 shows an enlarged view of the area around the door. A choke structure 20 consisting of a door front plate 18 and a door rear plate 19 is installed around the door 2, and the depth from the opening 21 of this choke structure 20 is approximately 1/4 of the wavelength of the radio waves used. By designing this, we were able to reduce the amount of radio wave leakage.

However, this zigzag structure 20 alone is not sufficient to meet the required performance, and it is necessary to install ferrite rubber 23 in which rubber is mixed with ferrite powder having radio wave absorbing properties in the sash portion 22.

This ferrite rubber is generally expensive and has radio wave absorbing properties, so when there is excessive radio wave leakage, it generates abnormal heat, sometimes leading to smoke and fire, which poses safety concerns.

Therefore, a method has been proposed to suppress radio wave leakage by dividing the radio wave path into two parts and generating a phase difference due to the difference in the shape of the path, instead of the Chiroku purchase 20, but this method Also, a space is required to constitute a radio wave passage (Japanese Patent Publication No. 58-30712).

The problem that the invention aims to solve, that is, even if it is a narrow structure using 1/4 wavelength,
Even with a structure in which a plurality of transmission lines of less than 1/2 wavelength are installed, the space occupied by the door seal device is still large, and the thickness of the door reaches several centimeters. This increases the weight of the side door, requires a door hinge that is durable due to the moment of inertia that occurs when opening and closing the door due to electrical transformation, and materials that can satisfy this need to be carefully selected, resulting in an expensive door. Additionally, there is a limit to how thin the door can be made to be, making it impossible to propose a progressively new product image in terms of the appearance and design of the microwave oven. This indicates a limit in the direction of the rate.

Reducing the volume of these doors is known to be a factor that can stimulate consumer demand, but in reality, there are aspects that conflict with the door seal performance that prevents radio wave leakage, and it is extremely difficult to make the door lighter and thinner. The problem was that it was difficult to

The present invention solves these conventional problems and provides an excellent door sealing device for a high-frequency heating device that has a simple structure, makes the door lighter and thinner, and achieves reliable door sealing. be.

Means to Solve the Problem The door sealing device for a high frequency heating device of the present invention is one in which an electric current for driving the high frequency generator is passed through a coil interposed between the door and the vicinity of the heating chamber opening. .

Function: The door seal device for a high-frequency heating device of the present invention has a coil covered with an insulating material sandwiched between the periphery of the heating chamber opening and the door, and when the high-frequency generator is emitting high-frequency electromagnetic waves, the coil is sealed. When the coil is energized, closed-loop lines of magnetic force are generated around the coil, thereby blocking high-frequency electromagnetic waves inside the heating chamber from leaking from the heating chamber entrance to the area around the door, thereby achieving door sealing. It turns out.

In addition, the door is made of ferromagnetic metal with a substantially flat plate shape, and a coil covered with an insulating material is fixed between the door and the metal surrounding the heating chamber opening. It is sufficient that the total thickness is less than Sam.

As a result of the above, it is possible to realize a door that is lighter in weight and thinner, and a stable door seal.

EXAMPLE Hereinafter, a door seal for a high frequency heating device according to an example of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 and 2, there is a carp (carp) V3 sandwiched between the periphery 1 of the heating chamber entrance and the substantially flat door 2.
/3 is the number of turns of one or more turns, and the insulation between the coil conductors is 4.
Insulated. This insulator 4 is provided with a retaining tab (not shown) that locks around the periphery 1 of the heating chamber opening and a screw tightening hole. Furthermore, a metal ring 5 is fixed to the inside and outside of the carp (carp) V3 using a ferromagnetic material. Furthermore, the door 2 is provided with a punched hole 7 having a diameter of 964 mm or less in a range of dimensions corresponding to the size of the heating chamber opening, and a hole 7 on the periphery 1 of the heating chamber opening is provided with a hole for locking the claw of the insulator 4 of the coil. hole 8 and screw tightening hole 9
It is configured such that the hinge 1o of the door 2 is processed.

As shown in FIG. 3, current is flowing through the coil 3 when electricity is flowing to the magnetron tube 11 or high-voltage transformer 12 as a high-frequency electromagnetic wave generator, and the switch 13. 14.15
．． 16, and the present invention is implemented by making the bottom of the circuit groove so that the coil cannot be energized when the door is open.

In this way, the high-frequency electromagnetic waves that are about to leak from the area around the heating chamber opening 1 to the area around the door 2 are blocked by the lines of magnetic force generated by energizing the coil/I/3, and the waves leak around the door 2. Since it cannot reach the door, a sufficient door seal can be created. Further, the door 2 does not need to have a built-in choke structure, and the door 2 can be made lighter and thinner. In addition, by winding the carp tV3 one or more times as in the present embodiment, strong lines of magnetic force are generated, making it possible to make china clay capable of blocking high-frequency electromagnetic waves. By providing the insulator 4 with the claws and screw holes 6, it is possible to shorten the working time when assembling the high frequency heating device.

By fixing metal rings 5 made of ferromagnetic material to the inside and outside of the coil 3, the lines of magnetic force generated by the coil/L/3 are prevented from attenuating between the periphery of the heating chamber entrance and the door 3. It has a preventive effect. Since the punching range provided on the door 2 corresponds to the size of the heating chamber opening, the entire inside of the heating chamber can be observed even when the door 2 is closed at the heating chamber opening.

Further, by providing a locking hole 8 and a tightening hole 9 around the heating chamber opening 1, the assembly work time can be shortened, and since the hinge 10 is processed, ,
The time required to install the door 2 can be shortened.

Effects of the Invention As described above, the door sealing function for a high-frequency heating device of the present invention is achieved by the magnetic field lines generated by energizing the coil sandwiched between the door and the periphery of the heating chamber opening. The structure of the door is simplified and the cost of the side door part is reduced.

In addition, the weight of the door is light, extending the life of repeated door opening and closing. By the way, when the coil is fixed around the opening of the heating chamber, it is possible to make the door lighter and thinner, improve the heating chamber's volume ratio, and propose a new product appearance, which is appealing to consumers. It is possible to propose product images that increase the customer's desire to purchase.

Furthermore, magnetic lines of force are obtained according to the number of turns of the coil, improving door sealing ability, and claws and holes provided in the coil insulator improve workability during assembly. This prevents the magnetic field lines from attenuating, and the punching process on the flat plate-shaped door corresponds to the size of the heating chamber opening, making it possible to observe the entire inside of the heating chamber, which is extremely advantageous in practical terms. It is.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional perspective view of a high-frequency heating device according to an embodiment of the present invention, Fig. 2 is an exploded perspective view of the same, Fig. 3 is an electric circuit diagram of the same, and Fig. 4 is a partial cutaway of a conventional high-frequency heating device. Perspective view,
FIG. 5 is a schematic configuration diagram of the same, and FIG. 6 is an enlarged sectional view of the same essential parts. 1...Around the heating chamber entrance, 2...Door,
3... Coil, 4... Insulator. Name of agent: Patent attorney Toshio Nakao and 1 other person1-
Figure 2 around the Ichikaro Juku room entrance 2-Door! Happy 4 Unexpected Figure 5

Claims (4)

[Claims] (1) A heating chamber in which food is stored and cooked inside the main body;
a heating chamber opening for taking food into and out of the heating chamber;
A high-frequency generator comprising: a door that blocks the heating chamber opening; a coil fixed to at least one of the periphery of the heating chamber opening and the door; and a high-frequency generator that radiates high-frequency electromagnetic waves into the heating chamber. A door seal device for a high-frequency heating device, wherein a driving current flows through the coil and generates a magnetic field around the coil, thereby creating a closed loop of magnetic lines of force between the periphery of the heating chamber opening and the door. (2) The coil has one or more windings, and the coil conductors are formed of an insulating material, and the insulating material is provided with protrusions and holes for tightening screws. A door seal device for a high-frequency heating device according to item 1. (3) Claims of a structure in which metal rings made of ferromagnetic material are provided inside and outside the coil to prevent lines of magnetic force generated around the coil from attenuating between the door metal and the metal surrounding the heating chamber opening. A door seal device for a high frequency heating device according to item 1. (4) The door is made of ferromagnetic metal and is approximately flat in diameter.
2. The door seal device for a high-frequency heating device according to claim 1, wherein punching holes of 4 or less are formed over an area corresponding to the size of the heating chamber opening.