JPH0315097B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to high frequency heating devices such as microwave ovens.

BACKGROUND ART As shown in FIG. 7, the heating chamber of a conventional high-frequency heating device such as a microwave oven has a structure including a U-shaped body plate 1 having outward flanges at the front and rear, and a guide plate on which, for example, a magnetron or the like is attached. It is equipped with a ceiling plate 2 having a wave tube 2a etc., a front plate 3 having a heated object inlet/outlet opening, an operation panel mounting opening, etc. on the front side, and a back plate 4 on the rear side, and each member is assembled by spot welding or the like. It was common to join them together using means such as caulking. The size of the opening in the front plate 3 for putting in and taking out the heated object is approximately the same size as the cross section of the U-shaped body plate 1, and the size of the opening for putting in and taking out the heated object is approximately the same as the cross section of the U-shaped body plate 1.
The space surrounded by is a heating chamber 9, and the flange portions used for joining each member are all located outside the heating chamber so that there are as few protrusions as possible inside the heating chamber 9. A high-frequency generator, its control device, and various electrical components are located in the space surrounded by the operation panel mounting opening in the front panel 3, the portion of the ceiling panel 2 that protrudes from the side wall of the body panel 1, and the end of the back panel 4. This will be an electrical room that will store the following items. In this way, since the protrusions of each of the above-mentioned members and various electrical parts will be installed outside the heating chamber, a chassis to fix them together and an outer shell material, for example, formed in an inverted U shape, to cover the whole are required. Is required.

The heating chamber 9 also requires painting or enameling treatment in order to maintain corrosion resistance against water vapor, boiled over water, food debris, etc. generated during heating of the object to be heated, that is, food. 1. This is done after the ceiling panel 2, front panel 3, back panel 4, etc. are joined together. There have also been cases where stainless steel plates have been used as the material to save time and effort in post-processing.

FIG. 8 shows another embodiment shown in USP 445291, in which the body plate 5 itself is formed into a square shape, and an inverted C-shaped electric chamber cover 6 is attached to the side surface of the body plate 5, and both are welded together by means of welding or the like. It is joined with. On the other hand, the front plate 7 and the back plate 8 having openings are connected to the body plate 5 and the electrical chamber cover 6.
After these are joined, they are attached to the front and rear of each, and after being welded to the flange portion of the body plate 5, the entire circumference is seamed to be integrally formed. According to this configuration example, there is no need to separately prepare an outer shell material or chassis. Regarding post-processing, please refer to Part 1.
The same is true for the example.

Problems to be Solved by the Invention According to the configuration of the first example described above, the heating chamber 9 and the outer shell material are separate members, so to speak, have a double structure, and the effectiveness of the heating chamber 9 with respect to the external shape of the device. The volume is small, and therefore the storage capacity for heated objects is limited. On the contrary, it has the disadvantage that the space occupied by the device is large compared to the capacity of the object to be heated. In addition, the heating chamber 9 and the outer shell are usually made of steel plates, which are heavy and difficult to transport, and the packaging material must also be sturdy. In addition, the welding of the heating chamber 9 is likely to result in partial welding defects depending on the conditions, and there is a risk that high frequency waves may leak from these areas. Furthermore, post-processing such as painting and enameling is time-consuming, which is also a factor in increasing costs.

On the other hand, according to the configuration of the second example, since the heating chamber and the outer shell material are integrated, it is possible to reduce the size and weight, but some parts still have joints such as welding, and post-painting is required. The drawbacks such as the necessity of this method are the same as those of the first conventional example.

The present invention solves the above-mentioned conventional drawbacks, has a single-layer structure, is small and lightweight, and saves space.
It is an object of the present invention to provide a high-frequency heating device having a heating chamber configuration that does not require the use of joining means such as welding or troublesome work such as post-painting.

Means for Solving the Problems In order to solve the above problems, the high-frequency heating device of the present invention uses a painted metal plate for its heating chamber.
A body plate formed in a letter shape, a bottom plate connected to the lower part of the body plate, a front plate having an opening for entering and exiting a heated object in the center having a size approximately equal to the inner dimension of the body plate, and the same size as the front plate. It consists of a back plate with an external size and an electrical chamber provided below the bottom plate, and the bottom plate has a convex portion that enters into the body plate from the lower ends of the front plate and the back plate, and The front plate and the back plate are joined together uniformly around the entire circumference.

Function The high-frequency heating device having the above configuration has a single structure with its external surface and the wall surface of the heating chamber, and the high-frequency generator and its control parts are stored separately in an electrical room and installed under the heating chamber, so the installation floor area is limited. can be made extremely small. In addition, by placing the electrical room at the bottom, the center of gravity is located downward, resulting in high installation stability. Furthermore, by positioning the effective bottom surface of the bottom plate above the lower ends of the front and back plates, the apparent height of the electrical room can be lowered, resulting in a compact and stable external appearance.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, the heating chamber 10 is
to form the ceiling and left and right sides, and the front plate 1
2 and the back plate 13 form the front and rear surfaces. The front plate 12 is provided with an opening 14 for entering and exiting the heated object, and is provided with a door 15 that can be opened and closed to close the opening 14. The floor plate 16 of the heating chamber 10 is made of a material with a low dielectric constant, such as reinforced glass, ceramic, heat-resistant plastic, etc., and is aligned with the lower end of the opening 14 in the front plate 12. The bottom plate 17 is located below, and its front and rear ends are connected to the front plate 12 and the back plate 13.
It is joined with. A magnetron 18 that generates high frequency waves is attached to the center of the lower surface of the bottom plate 17 with screws or the like, and an antenna 19 of the magnetron 18 passes through the bottom plate 17. A high-frequency stirring device 20 is provided around the antenna 19, which guides the wind generated by a cooling fan 21 for cooling the magnetron 18 through a guide plate 23 that communicates with a small hole 22 provided in the bottom plate 17. It rotates by.
The wind that rotates the stirring device 20 passes through the first small exhaust hole 24 in the lower part of the back plate 13, passes through the cover 25, and is discharged to the outside from the upper exhaust hole 26. Air containing heat and water vapor in the heating chamber 10 is pumped through the second exhaust hole 27 above the back plate 13 to the back plate 13 and the cover 25.
It is sucked in by the wind that passes between the two and is discharged at the same time.

The configuration of the heating chamber 10 is approximately an inverted U as shown in FIG.
The body plate 11 is attached to the lower part of the body plate 11 formed in a character shape.
A bottom plate 17 having the same dimensions as that of FIG.
As shown in FIG. 4, they are joined by folding and caulking to form a substantially square shape. The front plate 12 and the back plate 13 have approximately the same size as the joined cross section of the body plate 11 and the bottom plate 17, and are assembled at the front and rear ends, respectively, and then uniformly tightened around the entire circumference. . When tightening, flanges 11b and 17b are provided on the outer peripheries of the body plate 11 and the bottom plate 17, and longer flanges 12a and 13a are provided on the front plate 12 and the back plate 13, respectively, and the flanges 12a and 13a close the body part. flange 1
1b and 17b are wrapped and tightened in five layers as shown in FIG.

The bottom plate 17 has vertical wall surfaces 28 and 29 at the front and rear thereof, and these portions overlap with parts of the front plate 12 and the back plate 13. That is, as is clear from FIG. 1, the effective bottom surface of the bottom plate 17 is located above the lower ends of the front plate 12 and the back plate 13. Therefore, as shown in FIG. 6, the apparent height of the electrical chamber 30 that houses electrical components below the bottom plate 17 is lower than the electrical components that are housed inside. Furthermore, since the high-frequency inlet is located in the bottom plate 17, the high-frequency electric field inside the heating chamber 10 is stronger in the lower part, so even if high-frequency waves are thought to leak from a minute gap in the seaming part, for example, there is a possibility that the high-frequency electric field is lower. is high. However, as described above, the longer the portions of the front and rear surfaces 28, 29 of the bottom plate 17 that are in contact with the inner surfaces of the front plate 12 and the back plate 13, the longer the path of high frequency leakage becomes, and the amount of attenuation increases.

The body plate 11, the front plate 12, and the back plate 1
3 is formed by post-processing a metal plate that has been previously painted in a flat state, and only the bottom plate 17 is made of an unpainted metal plate in order to facilitate electrical conduction with the magnetron 18. This unpainted part is not suitable for external appearance as an exterior material, so the electrical room 30
needs to be large enough to cover the non-painted surface of the bottom plate 17 from being exposed to the outside.

In addition to forming the bottom plate 17 into a box shape by bending, it is also possible to form only the central portion into a convex shape by drawing. At this time, the front and rear vertical surfaces of the bottom plate 17 are aligned with the front plate 1 as shown in FIG.
2 and the back plate 13, but it is possible to wrap them tightly.

Effects of the Invention The heating chamber of the high-frequency heating device configured as described above can be expected to have the following effects.

(1) Since the outer shell material and the heating chamber have a single layer structure, the effective volume of the heating chamber can be large compared to the external dimensions, and the space occupied by the device can be relatively small.

(2) Since it has a single layer structure, it is lighter overall and convenient to transport.

(3) Relatively heavy items such as the high-frequency generator and its control parts are installed at the bottom of the heating chamber, so the center of gravity is located downward, resulting in high installation stability.

(4) The actual effective height of the bottom plate is above the lower ends of the front and back plates, which allows the apparent height of the electrical room to be lowered, resulting in a more stable appearance.

(5) By providing an overlapping area between the back surfaces of the front and back plates and the front and rear vertical walls of the bottom plate, the attenuation effect of high frequencies can be reduced even if the electric field tends to become stronger in the lower part due to the introduction of high frequencies from below. Since it is expensive, there is no need to worry about leakage.

[Brief explanation of the drawing]

FIG. 1 is a central vertical sectional 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 high-frequency heating device, and FIG. 3 is a connecting portion between the body plate and the bottom plate of the same high-frequency heating device. Figure 4 is a partial cross-sectional view of the 3rd stage before joining.
Figure 5 is a partial cross-sectional view of the seaming part of the same high-frequency heating device, Figure 6 is a vertical cross-sectional view of the same high-frequency heating device as seen from the front, and Figure 7 is a conventional high-frequency heating example. An exploded perspective view of the heating chamber of the device,
FIG. 8 is an exploded perspective view of a heating chamber of another conventional high-frequency heating device. 10... Heating chamber, 11... Body plate, 12... Front plate, 13... Back plate, 16... Floor surface, 17... Bottom plate, 18... Magnetron, 20... Stirring device,
30...Electric room.

Claims (1)

[Scope of Claims] 1. A body plate formed of a painted metal plate into an inverted U-shape, comprising a box-shaped heating chamber for accommodating an object to be heated, a high-frequency generator for supplying high-frequency waves to the box-shaped heating chamber, and a control device for the same. , a bottom plate connected to the lower part thereof, a front plate that is approximately the same size as the body plate and has an opening for entering and exiting heated objects in the center thereof, and a back plate that is approximately the same size as the front plate; an electrical chamber provided below the bottom plate; the bottom plate has a convex portion that extends into the body plate from the lower ends of the front plate and the back plate; A high-frequency heating device that is made by uniformly wrapping and joining each part around the entire circumference. 2 By bending the convex part of the bottom plate, it is formed into a box shape with vertical walls on the front, rear, left and right sides, and a flat top surface, and the front and rear surfaces of the vertical walls are formed on the inside of the front and back plates. The high-frequency heating device according to claim 1, wherein the high-frequency heating device has a configuration in which the two are in contact with each other.