JPS5987792A - 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 structure for mounting a front screen of a door provided at the opening of a heating chamber of a high-frequency heating device.

Structure of the conventional example and its problems In the case of the conventional high-frequency heating apparatus shown in FIGS. 1 and 2, for example, there is a heating chamber 1 provided in the main body for storing food, a magnetron and a high-voltage power supply circuit (not shown). ), the food is heated by high frequency waves generated by a magnetron.

The door body 3 is installed in a position facing the opening surface 2 of the heating chamber 1 so that it can be opened and closed laterally, and when the door is closed, the door key on the door side and the hook (not shown) on the main body side engage, and the door body 3 is opened. When you press the door opening button 5 on the C1 operation panel 4 that is in close contact with the surface 2,
The lock between the door key and the hook is released and the door opens.

Door body 3 (d1 A frame-shaped door outer frame 6 formed by drawing a metal plate,
A metal door middle frame 7 is integrally joined by spot welding and painted. The door middle frame 7 has a plurality of surface-treated metal door inner frames 8 and inner screen retainers 9.
It is rotated by screws 10 (approximately 0). The door inner frame 8 and the inner III screen retainer 9 sandwich the outer peripheral edge of the inner screen 11. The inner screen 11 is made of glass, polyester film, or the like. If
i-inside 111 screen 8 has φ0.6~φ311m8
A small hole is drilled through it to form a viewing window and at the same time prevent radio wave leakage.

On the other hand, on the front side of the door body 3, a screen frame 13 for holding an outer screen 12 is attached to the door outer frame. The outer screen 12 is made of glass or a resin plate such as acrylic,
The screen frame 13 is made of resin such as ABS or polyethylene terephthalate 1. As shown in the figure, the screen frame 13 is attached by being hooked with claws or the like using the elasticity of the resin. Further, the screen frame 13 has a wall surface parallel to the outer peripheral side wall of the door outer frame 6, and the door outer frame 6 is completely covered by the screen frame 13.

The space formed by the door outer frame 6 and the door inner frame 8 is a radio wave attenuation groove 14 which, together with a comb-shaped slit plate 16, prevents radio waves from leaking from the heating chamber 1.

Further, on the outer periphery of the door body 3, a metal side wall reflecting plate 16 is provided parallel to the outer peripheral wall of the door body 3 at a distance (about 2 to 3 mm) that does not hinder the opening and closing of the door body 3. ing. In the figure, the reflection plate 16 is processed integrally with the metal plate that constitutes the opening surface 2.

Further, at the entrance of the radio wave attenuation groove 140, a frame-shaped radio wave attenuation groove cover 1 made of a resin material such as polypropylene, polyethylene terephthalate, or polyphenylene sulfide is provided.
7 is placed. This radio wave attenuation groove cover 17 is pressed by the outer peripheral end of the door inner frame 8.

18 is the heating chamber wall, and 19 is a resin decorative frame.

20 is the outer box of the main unit, 21 is the timer, 22 is the heating star
Topotan and 23 each indicate a heating indicator lamp.

In the case of the door body of the high-frequency heating device having the above-described structure, the radio wave sealing function is first performed by sealing the radio waves by contact between the heating chamber opening surface 2 and the door inner frame 8. However, even though they are in contact, at least one of them has a 1:1 surface treatment applied to the insulator to prevent sparks, but the film thickness of this insulator is extremely thin (200~ (approximately 300 μm or less), it is equivalent to a conductive state in terms of high frequency, so the radio waves are nord. A gap is created, and radio waves leak outward through this gap.

However, due to the radio wave attenuation groove 14 and the comb-shaped slit plate 16 formed in the door body 3, the force 1j heat! : Most of the radio waves leaking from ζ1 are blocked here, and only a very small amount leaks to the outside. Such a radio wave control function prevents problems such as radio wave interference caused by radio wave interference of the high frequency heating device, adverse effects on the human body, and malfunction of electronic equipment, thereby ensuring safety.

By the way, the radio wave sealing performance of the door body 3 is affected by various factors, and the radio wave passageway is one of the factors. Therefore, if we pay attention to (1) of this radio wave path, we can see that the gap a between the outer peripheral wall of the door frame 6 and the reflective plate 16 located parallel to this on the periphery of the door body 3 and 'radio wave leakage 1a' ,
Looking at the relationship, the high frequency output is 600W and the water load is 27.
Figure 3 shows the condition of 5 CC. From this diagram, electricity? It can be seen that the 7J leakage amount does not change linearly with respect to the gap a, but increases exponentially as the gap a becomes narrower. In other words, the farther the reflective plate 16 is from the door outer frame 6, the worse the radio wave sealing performance becomes. According to the experimental results, a
When the amount tripled from 2M to 6ml, the radio wave leakage needle became 0.
．． It has quadrupled from 2 mw/ci to o, s mzv/crj.

Now, in the configuration of the conventional door body 3, the outer screen 1
Since the outer circumferential wall of the screen frame 13 made of resin sludge that holds the screen frame 13 covers the outer circumferential wall of the door outer frame 6, the gap (approximately 1 inch) between the screen frame 13 and the door outer frame 6 is /
The thickness of the frame 13 (approximately 2->m, the gap between the screen frame 13 and the reflective plate necessary for the body to open and close smoothly (approximately 2 to 3 zJ is the required dimension, and the total is approximately 5 to 6. As shown in Fig. 3, the radio wave sealing performance for the gap a is very poor.
It is easily affected by the tightness X1 performance between the heating chamber opening surface 2 and the door inner frame 8, and the oscillation stop device that responds to the opening and closing of the door body 3 requires a complicated mechanism that operates with a minute movement distance of the door body 3. This led to issues such as durability, reliability, and one-year productivity.

As mentioned above, providing an outer screen on the front of the door body is a very effective structure in terms of appearance performance and increasing product value, but it also has the disadvantage of improving radio wave sealing performance and the mechanism of the oscillation stop device. There are many problems and their solutions! r-y
It was strongly desired.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks, and aims to provide a high-frequency heating device having an extremely simple structure and an extremely high level of safety.

Structure of the Invention In order to achieve the above-mentioned object, the door body of the high-frequency heating device of the present invention is equipped with an outer screen on the front surface, and includes: an outer peripheral wall of the outer frame of the door, and a reflecting plate placed on the peripheral edge thereof. It is designed to minimize the gap between the two and further improve radio wave sealing performance, reliably preventing radio wave leakage, and solving problems such as radio wave interference, adverse effects on the human body, and malfunction of electronic equipment, thereby increasing safety. The present invention has the effect of improving reliability and productivity by not requiring a complicated operating mechanism of the oscillation stop device.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Identical parts are given the same symbols.

In Figures 4 and 6, a heating chamber 1 for storing food and performing high-frequency heating, a door body 3 that faces the heating chamber opening surface 2 and can be opened and closed freely, and a metal plate that is drawn and painted. A frame-shaped door outer frame 6, which is integrally joined to the door outer frame 6 by spot welding, and a door inner frame 7, which is then painted, and a small door frame of about φ0.5 to φ3 An inner screen 11 made of a resin film such as polyester or glass, placed in a position to cover a viewing window consisting of a group of holes, and an inner screen 1
A painted metal door inner frame 8 that holds the outer peripheral edge of the door frame 1 together with the door inner frame 7, a plurality of (about 10) screws 1o that fix the door inner frame 8 to the door inner frame 7, and The glass handle/ξ provided on the front side of the outer frame 6 includes an outer screen 12 made of a resin plate such as acrylic, and an AB that holds this outer screen 12.
II is formed by a screen frame 13 made of resin such as S or polyethylene terephthalate, an outer door frame 6, and an inner door frame 8.
a radio wave attenuation groove 14 in the space, a comb-shaped slit plate 16 made of metal and spot welded to the door outer frame, and a door outer frame 6.
A metal reflecting plate 16 located at the peripheral edge of the outer peripheral wall of the heating chamber wall, an Ik wave attenuation groove cover 17 made of a resin material such as polypropylene, polyethylene terephthalate, or polyphenylene oxide that covers the entrance of the radio wave attenuation groove 14, and a heating chamber wall. 18, a decorative frame 19 made of resin material #-1 such as ABS, and the outside i of the main body 20.

The outer screen 12 disposed on the front surface of the door body 3 is held at its outer circumferential end by a part of a screen frame 13, and the screen frame 13 has a plurality of locking claws 13.
It engages with the notch part of the door outer frame 6 by a and V. Furthermore, the outer peripheral wall of the door outer frame 6 is exposed, and the heating chamber opening surface 2
It faces a reflective plate 16 formed integrally with the side wall made of metal.

On the other hand, the outer shape of the screen frame 13 is approximately the same shape as the outer peripheral wall of the door outer frame 6, and the outer peripheral wall of the screen frame 13 and the outer peripheral wall of the door outer frame 6 are substantially on the same plane. ,
However, the outermost peripheral wall of the screen/frame 13, 1i13b facing the door outer frame 6, is made higher than the surface 13c in contact with the Nl/- surface on the front surface of the door outer frame 6.

The operation in the above t1q formation will be explained below.

The high frequency that flows into the heating chamber 1 is generated by three types of radio wave control functions, including the contact between the /JO heat chamber opening surface 2 and the door inner frame 8, radio wave attenuation'@14, and the combination of the slit plate 150. There is almost no electricity outside! It has a structure that prevents the skin from leaking, and is equipped with an outer screen 12 made of a resin plate such as acrylic or glass on the front of the door body 3, in order to improve the appearance performance and increase the product value. In this case, the gap a between the outer peripheral wall of the door frame 6 and the reflecting plate 16 would be large (about 6 to 6 mF4) in the conventional configuration, but it can be reduced to about 2 mm in this embodiment. . As can be seen from the experimental results in Figure 3, reducing the gap a is
Radio wave sealing performance is greatly improved, increasing safety.

Further, the state of the degree j at the outer periphery of the screen frame 13 and the door outer frame 6 is clearly shown in FIG.

The outer periphery of the door frame 6t, which is formed by drawing a metal plate, always has +lI = 1. R<1. A portion of this corner is hidden by the outer peripheral wall of the screen frame 13, and the door outer frame 6 and the screen frame 13 form substantially the same plane, reducing the gap at the joint to create a sense of unity and improve appearance performance. . In this embodiment, d, screen frame 13
Since the locking pawl 13a is in close contact with the door frame 6, the appearance and performance of the joint between the Sufu IJ-7 frame 13 and the door frame 6 are exactly the same as in the conventional structure. .

As described above, according to this embodiment, it is possible to provide a high-frequency heating device equipped with an outer screen on the front surface of the door with a simple configuration, and also to reduce the distance between the door frame J reflector and
This has the effect of further improving radio wave sealing performance.

Effects of the Invention As described above, according to the present invention, the following effects can be obtained.

(1) Since the radio wave sealing performance is further improved, problems such as radio wave interference due to radio wave leakage, adverse effects on the human body, and malfunction of electronic equipment can be prevented, and 1) - safety can be ensured.

(Takumi) Even if the response performance of the device (door switch) that stops radio wave oscillation to the opening and closing of the door is not particularly sensitive, it is possible to suppress the noise of radio waves to a sufficiently low level before the oscillation stop device is turned off. Reliability, durability, productivity, etc. are improved because a complicated mechanism that operates with a minute movement distance of the door is no longer necessary and can be simplified.

(31) Because the distance between the screen frame and the heating chamber opening is large, the temperature of the screen frame does not rise even if the heating chamber becomes hot due to long-term heating, so the heat resistance of the resin material is improved. It is also possible to drop the link or change to another grade, reducing the cost by one unit.

[Brief explanation of drawings]

Figure 1 is an external perspective view of a conventional high-frequency heating device, Figure 2 is a sectional view of the main part of the door body in Figure 1, and Figure 3 is the distance 1 between the door frame and the reflector and the radio wave law i leakage. 1 and 4 are cross-sectional views of the main parts of a door body of a high-frequency heating device according to an embodiment of the present invention, and FIG. 5 is an enlarged cross-sectional view of the main parts in Fig. 4.3, 1 Heating chamber, 2 “L” surface between heating chambers, 3 Door body, 6
・ Door frame, 12 outside (1111 screeno, 13
Screen frame, 14 radio wave attenuation groove, 16 reflector. Name of agent: Patent attorney Toshio Nakao and 1 other person
1 Plan? 2 2132Figure 20 11th block 53 Figure Q, (mm)

Claims (2)

[Claims] (1) A heating chamber that stores food, a high frequency generator that supplies high frequency power to the heating chamber, a door outer frame that forms a radio wave attenuation groove at a position facing the opening periphery of the heating chamber, and The screen frame includes an outer screen covering the front surface of the frame, a screen frame for holding the outer screen, and a metal side wall provided on the main body side at the periphery of the outer peripheral wall of the door outer frame.
The frame is made of a resin material, its outer shape is approximately the same as that of the outer frame, and the outer peripheral wall of the door outer frame, 1 = the outer peripheral wall of the screen frame, is substantially on the same plane. High frequency heating device. (2) High-frequency heating according to claim 1, wherein the surface of the outermost wall of the screen frame that faces the door frame is higher than the surface that contacts the flat surface of the front surface of the door frame. Device.