JPS6011436B2 - Heater device for high frequency heating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heater device for a high frequency heating device.

A heater that uses both normal dew heater heating and high frequency heating mainly in the microwave region in one heating chamber is an excellent cooking device and has a wide range of uses.

That is, the former feature of browning and the latter feature of fast cooking speed greatly expand its usefulness as a cooking device. Conventional heater devices can be broadly divided into the so-called "Shih Tzu heater" which covers a heat-generating resistance wire with a metal sheath through an insulator, as seen in U.S. Pat. No. 3,081,392, etc.;
Although there is an infrared heater element as seen in No. 243, the present invention mainly relates to the former type of sheathed heater.

Although the advantages of using both ordinary electric heating and high-frequency heating in one heating chamber have already been explained, there are also problems. it is,
This is related to cleaning inside the heating chain. Usually the heating chamber is
Although six-sided rectangular hollow steel is often used, the presence of the heater usually makes cleaning on at least one side very difficult. During cooking, food scraps, meat juices, etc. that fly off the food adhere to the interior of the heating chamber, staining the entire interior of the chamber, and this stain is usually relatively difficult to remove due to the phosphorizing effect of the heater. In particular, it is difficult to clean the surface of the heater element that is in contact with the shade. To solve this problem, it is effective to create a structure that allows the heater element to be easily attached and detached, but the prior art described above does not sufficiently address this issue. That is, in the prior art, screws or the like are used as means for fixing the heater in the heating chamber, which is inconvenient because a special tool is required for attachment and detachment, and repeated attachment and detachment may cause wear and tear on the fixing means. There is a danger that due to destruction, complete adhesion may not occur, and high frequency leakage from the power supply section may increase. Therefore, there is a need for a heater device that has a heater element that can be easily installed and removed within the heating chamber, has little leakage of high frequency waves, and can ensure sufficient safety even in the event of electrical leakage due to deterioration of the insulation of the sheathed heater.

An object of the present invention is to provide, in a heater that uses both a normal heater and high-frequency heating in the same refrigerator, a configuration in which a heater element can be easily attached and detached from a power supply section of the normal heater provided on the inner wall of the refrigerator.

Another objective is to reduce high frequency leakage in the power supply of the heater element.

Another object is to provide a structure that is safe against electric leakage due to insulation deterioration of the heater element.

Another purpose is to prevent spark discharge and deterioration of sealing performance in the heater element power supply section.

A detailed explanation will be given below according to the drawings.

In FIG. 1, reference numeral 1 denotes a heating chamber, and high frequency waves generated by a high frequency oscillator 2 are transmitted to the heating chamber 1 through a waveguide 3. 4 is a fan motor for air cooling the oscillator, and a portion 5 surrounded by an imaginary line is a power supply section for the high frequency oscillator.

6 is a heater element, 7 is a choke member for preventing radio wave leakage, and 8a, 8b, 8c are heater elements and grounding lead wires.

Reference numeral 9 denotes a heater element support fitting, which also functions as a guide rail when attaching and detaching the heater element.

Reference numbers 10 and 11 surrounded by two-dot chain lines (imaginary lines) are the door and handle.

12 is the top mark and 93' is the operation knob.

FIG. 2 shows a cross-sectional view of a typical example of a heater element.

In the Nichrome wire heater coil of Tomishima, numeral 16 is an insulator made of lime, alumina, magnesia powder, etc., and 16 is a metal sheath, and stainless steel or the like with low magnetic permeability is suitable as the metal. 17 is electrode 1, 18 is electrode 0, and electrode 117 connects electrode 018 and heater coil 14.

19 is a sealing insulator made of glass or porcelain.

FIG. 3 shows the overall configuration of the heater element 6.

18a, 18b are power supply electrodes, 20 is a grounding electrode, 21
is the power supply base metal cover.

Details of the power feeding section are shown in FIGS. 4 to 7.

In the figure, the same numbers as above indicate the same members, 16a, 1
6b is a metal sheath, 17a and 17b are electrodes 1, and 22 is an insulator provided in the metal cover 21. A structural feature of the present invention is that the metal sheaths 16a and 16b are at a common potential with one metal cover 21. To make them electrically at the same potential, they can be mechanically compressed or soldered with silver solder or the like. Another feature of the present invention is that the grounding electrode 20 is at a common potential with the metal cover 21. Furthermore, an insulator 22 for insulation provided inside the metal cover 21
Another feature is that it prevents mechanical deviation of each electrode.

Furthermore, the fact that the lengths of the grounding electrode 20 and the power feeding electrodes 18a and 18b are not the same is a structural feature that is effective for positioning when inserted into a receptacle (not shown). . However, this is not the essential content of the present invention. Further, although the embodiments illustrate a rectangular metal cover 21, the present invention includes many other shapes such as an ellipse.

FIG. 8 shows a configuration in which the heater element of the present invention is attached to the wall of the heating chamber.

The choke member 7 for preventing radio wave leakage is a choke member A23,
It has a choke groove 25 made up of a choke member B24. An insulating spacer 26 prevents the metal cover 21 and the heating chamber wall 30 from coming into contact with each other and causing spark discharge or the like.

Although not shown in detail, 28 is a receptacle portion, the outer shape of which is shown with imaginary lines. 27 and 29 are screws for fixing the choke member, the heating chamber, and the receptacle.

In the fin diagram, the radio waves leaking from the gap between the main body wall and the metal cover can be reduced by setting the effective depth of the choke groove 25 marked with diagonal lines to nearly one-fourth of the wavelength of the oscillated radio wave. It can be done.

If necessary, a means for detecting whether or not a heater element is attached to a choke member for preventing radio wave leakage shall be provided to prevent unauthorized use without the heater element being attached, and when the heater element is not attached.
A means for physically sealing the opening facing the heating chamber of the choke member for preventing radio wave leakage may be provided.

Furthermore, it is effective to make the maximum diameter of the closed part of the choke member for preventing radio wave leakage less than half of the wavelength of the radio waves being used, since it can reduce leakage of waves outside the head even when used without inserting a heater element. be. By adopting the configuration of the present invention as described above, the following effects can be expected.

(i) The heater element can be easily attached and detached without any special tools, and the entire surface of the heating chamber can be easily cleaned.

(ii) Since the structure is such that the metal cover electrically connects the plurality of cypress pods to a common potential, radio wave sealing can be achieved with only one choke structure, and the configuration is simple.

(iii) Even if the insulation between the heater and the sheath deteriorates when the heater temperature rises abnormally or the end of the sheathed heater gets wet, the provision of a grounding electrode will ensure that the sheath and metal cover remain connected. Since they are configured at the same potential, dangers due to electrical leakage can be prevented.

Since the OW choke structure is provided outside the heating chamber, it is easier to consider radio wave design, especially for making the electric field distribution uniform.

M Since there is an insulating spacer provided on the heating chamber wall surface, there is no contact between the metal cover part, the heating chamber wall surface, and the choke structure member, and it is possible to prevent sparks from occurring and deterioration of sealing performance.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of a high-frequency heating device equipped with a heater device according to an embodiment of the present invention, FIG. 2 is a sectional view of a main part of a heater element of the heater device, and FIG. 3 is an overall configuration diagram of the heater element. FIG. 4 is a longitudinal cross-sectional view of the power supply section of the heater device, FIG. 5 is a side cross-sectional view of the power supply section, FIG. 6 is a view taken along the line A-A in FIG. 5, and FIG. FIG. 8 is a cross-sectional view showing the structure of the attachment portion of the heater element to the heating chamber wall. 1... Heating chamber, 2... High frequency oscillator, 6...
... Heater element, 7 ... Choke member for preventing radio wave leakage, 10 ... Door, 16, 16a
, 16b...metal trouble, 18, 18a, 18b...
・Power supply electrode, 20... Grounding electrode, 21...
Metal cover, 22... Insulator for insulation, 26... Insulator surface, 30... Heating chamber wall. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Scope of Claims] 1. A high-frequency oscillator, a heating chamber, a door that closes an opening of the heating chamber, a heater surrounded by a sheath made of a conductive metal material in the heating chamber, and a power supply for the sheath of the heater. The heater element has a high conductivity contact with one metal cover part in the part, and a chiyoke structure for preventing radio wave leakage provided on the wall surface of the heating chamber. A heater device for a high-frequency heating device, wherein the heater element has an electrode for supplying power to the heater and is detachable, and the metal cover has a grounding electrode. 2. The heater device for a high-frequency heating device according to claim 1, wherein the radio wave leakage prevention member provided on the wall surface of the heating chamber is provided outside the wall surface. 3. The heater device for a high-frequency heating device according to claim 1, wherein an insulator is interposed between the metal cover, the power feeding electrode, and the grounding electrode. 4. The heater device for a high-frequency heating device according to claim 1, further comprising a spacer made of an insulator for holding the metal cover at a position higher than the bottom surface of the cross-sectional opening of the inlet of the chi-yoke structure. 5. The heater device for a high-frequency heating device according to claim 1, further comprising an insulating spacer having an opening smaller than the side-to-side dimension of the inlet cross-sectional opening of the chi-yoke structure.