JPS58195715A - High frequency heating device - Google Patents

Abstract

PURPOSE:To reduce the number of component parts and to improve an assembling efficiency, by a method wherein frames having an approximately ?-shape in cross section are mounted to 3 sides of the outer frame of a door covering an open face of a heating chamber, and a front screen is housed and held within the frames. CONSTITUTION:A door 5 for opening and closing an open face 3 of a heating chamber 2 is formed such that an outer door frame 6 and a middle door frame 7, all made of a metal, are constructed integrally by welding, a metal screen 8 and a inner screen 10 formed of glass are positioned between the nip formed by the middle door frame 7 and an inner door frame 6. In which case, a right front door frame 24, a left front door frame 25, and a lower front door frame 26 are monolithically adhered to the front of the outer door frame 6 by welding. Each of the right and left frames 24 and 25 is bisymmetrical having an approximately ?-shape in cross section, and a lower frame 26 is formed in an approximately ?-shape in cross section having a slope at the bottom side thereof. After a front screen 16 is inserted into ?-shape channel formed of said frames 24 and 26, an upper front frame 27 is pressed in, and a handle 20 is then secured by means of a screw to complete the door 5.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to means for holding a screen on the front surface of a door of a high-frequency heating device.

A door is provided on the opening surface of the 770 heat chamber of the high frequency heating device so that it can be opened and closed freely.The door not only prevents the high frequency waves generated inside the heating chamber from leaking outside, but also serves as It has a structure that allows you to see the heating state of the heated object from the outside. Furthermore, recently, design elements have been added to the doors as products, and doors with screens made of glass or plastic on the front of the door are also being sold.

However, the structure for holding the front screen of the door in and fLt was complicated due to the large number of parts, and there were also problems in terms of radio wave leakage prevention performance. Regarding a conventional example, the configuration of a high frequency heating device equipped with a vertically swinging door will be described below with reference to FIGS. 1 and 2.

A heating chamber 2 in the main body 1 is equipped with a magnetron that generates high frequency waves and a high voltage power supply (not shown), and is provided with a door 6 that faces the opening surface 3 of the heating chamber and is rotatable about a rotation axis 4. . The door 6 has a structure in which a metal outer door frame 6 and a middle frame 7 are integrally formed by spot welding, and a metal screen 8 consisting of a group of small holes and a mouth-shaped rubber frame 9 are provided on the outer periphery. An inner screen 1o made of glass is provided with a screw 12 between the inner door frame 11 made of metal whose surface is treated with an insulating material and the inner frame 7 of the lung.
It is held in place by The space formed by the door outer frame 6 and the door inner frame 11 is a radio wave attenuator 13, and a cover 14 made of low dielectric or heat-resistant plastic is held at the entrance thereof.

A plastic door outer frame 15 is arranged on the outside of the door 6. An outer screen 16 made of resin such as acrylic or reinforced glass is attached to the door outer frame 6 and the door outer frame 16. being held in place. The door outer peripheral frame 16 is fixed from the inside of the door outer frame 6 with screws 17. A part of the body 18 and a lower sash 19 are arranged on the periphery of the door 5 in parallel with the door outer peripheral frame 15, and these are all made of metal material. 20 is a handle, 21 is a timer knob for setting heating time provided on the operation panel 22, and 23 is a heating start button.When heating the object to be heated with high frequency, set the timer knob 21 to the required time. When the heating start button 23 is pressed, the heating starts. When the timer goes off, the housing is structured so that if the door 5 starts to open during heating, the generation of high frequency waves will stop.

By the way, the outer screen 16 & of the high frequency heating device. , Iku, 5-:...8oei6. There are also growing demands for design, such as enhanced heat resistance by combining the functions with ayui, 7-bun.

As a result, the structure becomes very complex, the number of parts increases, and the number of man-hours required for manufacturing and service increases, which causes an increase in costs.

Furthermore, the high frequency generated in the heating chamber is
The radio wave is attenuated by the capacitive seal formed by the heating chamber opening surface 3 and the door inner frame 11 and the radio wave attenuation groove, and is safe with almost no leakage.
It has been experimentally confirmed that this is greatly influenced by the width of the passageway. That is, the smaller the gap ttet2 between the outer peripheral wall of the door outer frame 6 and the body 18 and the lower sash 19, the better the radio wave sealing effect is.

However, in the conventional configuration, since the door outer frame 6 is covered with the door outer frame 16 made of plastic, there is a gap t1s t2.
becomes large, at least 5111J in the conventional case
If the radio wave sealing performance is insufficient, it is also possible to place a radio wave absorber (not shown) in the middle of the radio wave attenuation groove 13 and inside the door outer frame 15. there were.

The present invention solves the above-mentioned problems in the conventional example. In other words, it reduces the number of parts, improves workability, further improves the radio wave sealing performance, ensures safety, and offers a wide range of products with various designs. Therefore, it is possible to provide a high-frequency heating device with a door structure that can satisfy the customer's requirements.

An embodiment of the present invention will be described below with reference to FIGS. 3 to 5 using an example of a high-frequency heating device equipped with a vertical enclosure door.

A door 5 is provided opposite the opening surface 3 of the heating chamber 2 and rotatable about a rotating shaft 4. The door has a metal outer door frame and a door inner frame 7 that are integrally formed by spot welding or the like, and is made of glass with a metal screen 8 consisting of a group of small holes and a U-shaped rubber frame 9 on the outer periphery. The inner screen 1o has a metal door inner frame 11 and a door middle frame 7 whose surfaces are treated with an insulating material.
It is clamped by a screw 12 between them. The whole area constituted by the door outer frame 6 and the door inner frame 11 is a radio wave attenuation groove 13, and the entrance thereof is held by a cover 14 made of a low dielectric material or heat-resistant plastic.

- On the front side of the gal outer frame 6, there is a door front frame right 24, a left door front frame 26,
The lower door front frame 27 is spot welded and painted. The right door front frame 24 and the left door front frame 26 are bilaterally symmetrical, and have a substantially U-shaped cross section. Lower door frame 26
is configured to be flush with the right door front frame 24 and the left door front frame 26, and the lower side thereof is an inclined surface, so that when the door is opened and closed, the bottom 1
The angle is such that the distance t2' with respect to 9 is sufficiently small.

The outer screen 16 includes a door front frame right 24, a door front frame left 26,
It is inserted and held in a U-shaped groove formed in the lower right corner 26 of the front door frame, and the width a of the groove is larger than the thickness b of the outer screen. This is because when the outer screen 16 is made of tempered glass, it is necessary to allow a distortion of about 0.3% in the plane of the glass with variations in thickness of ±10×1. Therefore, in order to prevent the outer screen 16 from rattling, the lower ends of the spot welding surfaces of the right and left door front frames 24 and 26 are formed into a substantially dogleg shape to absorb the rattling of the lower part of the outer screen 16, and to The top 27 of the door front frame, which has a roughly doglegged protrusion, is completely press-fitted to absorb the rattling of the top.

In particular, the upper part of the door front frame 2:r has a roughly doglegged protrusion near the center, which eliminates the gap between the door outer frame 6 and the outer screen 16 to prevent water and dust from entering. , the cut surface of the glass is covered so that it cannot be seen.

After press-fitting the door front frame top 27, if the handle 2o is fixed with a screw, the door front frame will come into contact with the base of the handle 2o and the outer screen 16 will not come off.

Figure 6 shows the assembled door.

According to the structure of the present invention as described above, ■ Among the parts that make up the door, all the parts that hold the outer screen are constructed integrally with the door outer frame and then painted, so the number of parts is small and the assembly work is easy. This allows for simplification in terms of performance and management.

■ The right and left door front frames are almost unaffected by variations in the thickness of the outer screen and distortion of the plane.

□ You can eliminate the gap between you and the other person, so you can use Buzaro・1・
1) Product A': also has good knee-in performance.

■ Since there is no plastic frame on the outer periphery of the door frame, the door frame and body 18 are essentially the same.
and a gap t1' with the lower satshee 19.

t2' can be configured to be sufficiently smaller than conventional tl and t2. (2 to 3 I is possible in the case of the embodiment) As a result, the effect of the radio wave attenuation groove is further enhanced, the radio wave sealing property is improved, and safety is increased.

Effects such as these can be obtained.

[Brief explanation of drawings]

Figure 1 is an external perspective view of a conventional high-frequency heating device;
Fig. 2 is a cross-sectional view of the door, Fig. 3 is a cross-sectional view of the door of a high-frequency 71tl power device according to an embodiment of the present invention, Fig. 4 is a perspective view of the external appearance of the same, and Fig. 6 is the outer screen of the same. FIG. 3 is an external perspective view of the door with the door attached. 6...Door outer frame, 16...Outer screen, 18...Body, 19...Sash bottom, 20...Handle, 24 ...Front of face: Right frame, 26... Left front frame of door, 26...
・Bottom door front frame 1. ．． 27...On the front frame of the door. i. Name of agent Benjiku: En Toshio Nakao and 1 other person
Name □,,: Figure 1 Figure 3

Claims (1)

[Claims] A heating chamber having an opening to which high frequency power is supplied, a door that covers the heating chamber so as to be openable and closable, and a door provided on three sides of the front peripheral edge of the field, the cross section of at least a pair of opposing sides being approximately A high-frequency heating device comprising a frame for holding a front screen in the shape of an opening, and a front screen held by the frame.