JPS61208786A - 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] Industrial applications The present invention relates to a leakage radio wave prevention structure for a high frequency heating device.

Conventional technology Is it a flange installed around the opening of the heating chamber?

Alternatively, Japanese Patent Publication No. 51-17732 proposes a method for preventing leakage of radio waves by continuously providing a plurality of radio wave attenuation grooves on at least one side of the periphery of the door facing the door.゛Problems to be Solved by the Invention The object of the invention in which a plurality of radio wave attenuation grooves are provided on the flange near the opening of the heating chamber or on the periphery of the door facing the opening is to prevent leakage of radio waves near the fundamental wave. Moreover, the parts that make up the radio wave attenuation groove become larger, and the structure of the flange part and the door part become larger, resulting in an impractical structure. There was a problem in that the main body of the device also increased in size, and if the installation location was expanded, the weight would also increase.

Means for Solving Problem '' A radio wave labyrinth for preventing leakage of the fifth harmonic and for preventing leakage of the fundamental wave is separately provided in the periphery of the flange and in the periphery of the door opposite thereto, respectively.

A radio wave labyrinth for preventing 5th harmonic leakage with a cavity with a depth of approximately V20 is installed around the working flange, and a depth of approximately λ/4 is installed around the door.
By providing each radio wave labyrinth having a cavity for preventing fundamental wave leakage, radio wave interference to not only the fundamental wave but also the frequency band used for recent satellite broadcasting is prevented. Furthermore, since each radio maze is provided independently on the flange and door, the flange and door can be made smaller.
The high-frequency heating aft itself can also be designed compactly.

Embodiment The structure and operation of a high-frequency heating device according to an embodiment of the present invention will be explained with reference to the drawings.

1 is a heating chamber, 2 is a door attached to the front opening of the heating chamber 1 so that it can be opened and closed freely, 3 is a main body cover of the high-frequency heating device,
4 are high frequency oscillators 5 to 9 installed on the ceiling of the heating chamber 1;
This is a starter for stirring the emitted high frequency energy. 6 is a radio wave maze for preventing fifth harmonic leakage, which is provided along the entire circumference of the flange 7 around the opening, and its depth is C.
1ki λ. /20 (λo=122 ho). 8 is door 2
A radio wave maze for preventing fundamental wave leakage is provided around the entire circumference, and is composed of a door rear plate 9 that contacts the flange 7 and a door front plate 10 around the door 2, and has a depth C and pλ. /4.

Next, the effects of the above embodiment will be explained.

From the heating chamber 1 to the door rear plate 9. The high frequency energy leaked between the flange 7 is λ in the depth C1 configured in the flange 7.
. /20 cavities. At the entrance 6a of the radio maze 6 for preventing leakage of the fifth harmonic, the impedance becomes infinite for the fifth harmonic, so the leaked fifth harmonic is blocked. Furthermore, the fundamental wave that passes through the radio wave maze 6 for preventing fifth harmonic leakage has the same depth λ of the cavity of the radio wave maze 8 for preventing fundamental wave leakage as described above. /4, the impedance at the entrance 8a becomes infinite and leakage to the outside is prevented. 5th harmonic leakage prevention radio wave maze on the flange 7 and the door 2 periphery 6. Radio maze 8 for preventing fundamental wave leakage
This not only prevents radio wave interference to the fundamental wave but also to the frequency band for broadcasting satellites, a small radio maze 6 for preventing fifth harmonic leakage is installed on the flange 7, and a large fundamental wave leakage prevention device is installed. Since the radio wave maze 8 is installed on the door 2 side,
The 7 flange parts and the 2 door parts do not become larger as in the past.

Effects of the Invention As described above, according to the present invention, a radio wave maze for preventing fundamental wave leakage is formed around the door, and a radio wave maze for preventing fifth harmonic leakage is formed around the flange.

It has a leakage prevention function not only for the fundamental wave but also for the 5th harmonic of the frequency band for broadcasting satellites.

By individually installing each radio wave maze in the flange portion and the door portion, it is possible to prevent the high-frequency heating device from increasing in size, and to provide a compact and easy-to-handle high-frequency heating device.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of a high-frequency heating device according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of the radio wave labyrinth section of FIG. 1. 1... Heating chamber. 2...door. 6.8... Radio maze. 7...7 lunges.

Claims (1)

[Claims] Flange (7) provided around the opening of the heating chamber (1)
Radio mazes (6) and (8) are respectively formed around the door (2) facing this, and the depth (C_1) of the radio maze (6) provided on the flange (7) is approximately λ_ ■/2
0 (λ_■=122 mm), and the depth (C_2) of the radio maze (8) provided around the periphery of the door (2) is approximately λ_■/4.