JP2563573B2 - High frequency cooking device with heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a high-frequency heating cooking device with a heater having a tubular upper heater in the upper part of a heating cooking chamber.

(Prior Art) Conventionally, this type of high-frequency heating cooking device with a heater is
As shown in FIG.
And a tubular upper heat 3 is arranged in the heater housing 2. In this case, the support structure of the upper heater 3 penetrates both ends of the upper heater 3 into the heater through holes 4 on the left and right end surfaces of the heater housing 2, and supports the both ends of the upper heater 3 by the support member 5 outside. It is like this.

In such a structure, at the time of high frequency heating, the high frequency (microwave) propagates through the coiled nichrome wire 3a at the center of the upper heater 3 and is concentrated near the heater through hole 4, whereby the coiled nichrome wire 3a and the heater penetrating hole are penetrated. There is a possibility that a large electric potential difference is generated between the hole 4 and the peripheral edge of the hole 4 and a spark is generated. Such a spark is likely to occur particularly when there is no food (load) in the heating cooking chamber 1.

As a means for preventing the occurrence of such a spark, in recent years,
As shown in FIG. 9, there is a heater in which a cylindrical high frequency attenuator 6 is mounted inside the heater through hole 4 and the high frequency attenuator 6 covers both sides of the upper heater 3.

(Problems to be Solved by the Invention) However, when both sides of the upper heater 3 are covered with the high frequency attenuator 6, the radiant heat of the upper heater 3 is shielded in the portion covered with the high frequency attenuator 6 for cooking. Since it cannot contribute to the heating of the food, there is a problem that the effective heating area of the upper heater 3 is sandwiched and the heating efficiency is deteriorated, and the heating of the peripheral portion of the cooked food is not insufficient.

The present invention has been made in consideration of such circumstances, and therefore an object thereof is to prevent sparks from being generated at the peripheral portion of the heater through hole without sandwiching an effective heating area of the upper heater, thereby preventing the occurrence of sparks and the upper heater. An object of the present invention is to provide a high-frequency heating cooking device with a heater that can achieve both maintenance of heating performance.

[Structure of the Invention] (Means for Solving the Problems) A high-frequency heating cooking device with a heater according to the present invention is a magnetron for high-frequency heating a food in a heating cooking chamber, and heaters formed on both upper sides of the heating cooking chamber. A tubular upper heat that is penetrated through the through hole, characterized in that a high-frequency reflector is provided near the heater through hole in the heating and cooking chamber so as to be close to the upper heater upper side. It is a thing.

(Operation) Since the high-frequency reflector is provided on the upper side of the upper heater, the lower side of the upper heater is not blocked by the high-frequency reflector. Therefore, when the oven is heated, the radiant heat of the upper heater is radiated to the cooked product without being blocked by the high-frequency reflecting section, and the effective heating area of the upper heater is not narrowed by the high-frequency reflecting section. In this case, in the vicinity of the heater through-hole, the high-frequency reflection portion is close to the upper heater, so during high-frequency heating, the high-frequency reflection function of the high-frequency reflection portion causes a gap between the heating wire in the upper heater and the high-frequency reflection portion. At this time, an action of an attenuator for attenuating the high frequency occurs, whereby the electric field around the heater through hole is relaxed and the generation of sparks is prevented.

(Embodiment) A first embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

First, in FIG. 1 showing a vertical sectional front view (the outer box is not shown), 11 is an inner box having a heating and cooking chamber 12 inside, and a motor 13 is rotationally driven in the center of the bottom of the box. A rotating dish 14 is provided. A lower heater 15 is arranged between the rotary plate 14 and the bottom plate of the inner box 11. On the other hand, a waveguide 16 is attached to the right side surface of the inner box 11, and a magnetron 17 is fixed to the waveguide 16. 18 is the inner box
With a reflector attached to the center of the upper surface of 11 by welding,
As shown in FIG. 2, this reflection plate 18 is formed so as to project upward in a trapezoidal shape and extend in the left-right direction, and the lower surface side of the reflection plate 18 is cooked through the rectangular opening 11a in the upper surface of the inner box 11. It is open to the inside of chamber 12. And this reflector 18
An upper heater 19 made of a glass tube heater is arranged at the inner center of the so as to extend in the left and right directions. As shown in FIG. 3, the mounting groove of the upper heater 19 is formed by the end plate portion 18 of the reflection plate 18.
In a, a cylindrical portion 20a forming the heater through hole 20 is formed so as to project outward, and an upper insulator 19 is supported by an annular insulator 21 fixed to this cylindrical portion 20a and fixed to the upper surface of the inner box 11. The mounting plate 22 regulates the horizontal movement of the upper heater 19.

Then, in the vicinity of both heater through holes 20 in the heating and cooking chamber 12, a high frequency reflection portion 23 is provided so as to be close to the upper side of the glass tube 19b of the upper heater 19, respectively. In this embodiment, each high-frequency reflector 23 is made of a metal (for example, iron, copper, aluminum, etc.) in a half-split cylinder shape, and is used as an upper heater.
The upper half of 19 is covered (see FIG. 2), and the mounting piece 23a formed at the end is fixed to the end plate 18a of the reflection plate 18 by welding or the like. Has been done. In this case, the horizontal protrusion size of each high-frequency reflector 23 is the high frequency (microwave) generated by the magnetron 17.
The length is set to approximately 1/4 of the wavelength λ of. Further, the dimension between both end plate portions 18a of the reflection plate 18 is about 2 of the high frequency wavelength λ.
It is set to double size.

According to the above configuration, since the high frequency reflection part 23 is provided on the upper side of the upper heater 19, the lower side of the upper heater 19 is not blocked by the high frequency reflection part 23. Therefore, when the oven is heated, the radiant heat of the upper heater 19 is generated by the high frequency reflection portion 23.
The high heat reflecting portion 23 does not sandwich the effective heat generation area of the upper heater 19 because the radiation is emitted to the food side on the rotary dish 14 without being blocked by the. Therefore, the heating by the upper heater 19 can be efficiently performed without waste, the heating efficiency can be favorably maintained, and insufficient heating of the peripheral portion of the cooked food can be eliminated.

On the other hand, in the vicinity of the heater through hole 20, since the high frequency reflection portion 23 is close to the upper heater 19, the high frequency reflection action of the high frequency reflection portion 23 causes the heating wire 19 in the upper heater 19 to move.
The action of an attenuator for attenuating the high frequency occurs between a and the high frequency reflection part 23, whereby the electric field around the heater through hole 20 is relaxed and the generation of sparks is prevented. Such a spark generation preventing effect has been confirmed from the experimental results of the present inventor, and in particular, as in the above-mentioned embodiment, the high frequency reflector
It has been confirmed that the spark generation prevention effect is remarkably enhanced when the protruding dimension of 23 in the left-right direction is set to a length of approximately 1/4 of the high-frequency wavelength λ.

In the above embodiment, the high frequency reflection portion 23 is formed in a half-split cylinder shape, but the shape can be variously modified, for example, in the second embodiment of the present invention shown in FIGS. 4 and 5. As described above, the high frequency reflection part 25 is formed in a substantially L shape, and the high frequency reflection part 25 is provided in the vicinity of the heater through hole 20 in the cooking chamber 12 and in the vicinity of the upper side of the upper heater 19. Is also good. In this case, the high frequency reflection part 25 is
The mounting piece 25b at the upper end of 25a is fixed to the inner surface of the reflection plate 18 by welding. In this fixed state, the reflector
The dimension between the end plate portion 18a of 18 and the vertical portion 25a of the high frequency reflection portion 25 is set to a length of approximately 1/4 of the wavelength λ of the high frequency, and the tip of the horizontal portion 25c is in the heater through hole 20. Are in close proximity. However, a gap (for example, 3 to 4 mm) between the tip of the horizontal portion 25c and the peripheral edge of the heater through hole 20 to the extent that sparks are not generated.
There is a gap of (about). The other structure is the same as that of the first embodiment.

Also in such a second embodiment, it is possible to obtain the same effect as that of the first embodiment.

In the first and second embodiments described above, the high frequency reflector 2
Although 3,25 are formed by a member different from the reflector 18, for example, the sixth
As in the third embodiment of the present invention shown in FIG. 7 and FIG. 7, the left and right side portions of the reflection plate 18 are formed into a concave shape by drawing.
The high frequency reflector 26 may be formed integrally with the reflector 18. In this case, the high-frequency reflection part 26 is formed in an arcuate cross section, and the high-frequency reflection part 26 is located in the vicinity of the heater through hole 20 in the cooking chamber 12 and above the upper heater 19 as in the first embodiment. The form is close to the side. Also in this case, the horizontal dimension of the high-frequency reflector 26 is set to the high-frequency wavelength λ.
The length is set to about 1/4. The other structure is the same as that of the first embodiment.

Also in the third embodiment, it is possible to obtain the same effect as that of the first embodiment. Moreover, in this case, since it is not necessary to weld the high frequency reflection portion 26 to the reflection plate 18, there is an advantage that the assembly efficiency is improved.

The present invention is not limited to the first to third embodiments described above, and for example, the support structure of the upper heater 19 may be changed, the cross-sectional shape of the reflection plate 18 may be changed, and the like. Various modifications are possible.

[Effects of the Invention] As is apparent from the above description, the present invention has the high-frequency reflector provided near the heater through-hole in the cooking chamber so as to be close to the upper side of the upper heater. It is possible to prevent the occurrence of sparks at the peripheral portion of the heater through hole without narrowing the heat generation area, and it is possible to prevent the occurrence of sparks and maintain the heating performance of the upper heater at the same time.

[Brief description of drawings]

1 to 3 show a first embodiment of the present invention. FIG. 1 is a vertical sectional front view of a heating and cooking chamber portion, and FIG. 2 is an enlarged vertical side view of a peripheral portion of a reflector. FIG. 4 is an enlarged vertical front view of the support structure portion of the upper heater, FIGS. 4 and 5 show a second embodiment of the present invention, and FIG. 4 is a view corresponding to FIG. 1 and FIG. Is a drawing corresponding to FIG. 2, FIGS. 6 and 7 show a third embodiment of the present invention, FIG. 6 is a drawing corresponding to FIG. 1, and FIG. 7 is a cutaway perspective view around the high-frequency reflector. Is. And, FIG. 8 and FIG. 9 are vertical sectional front views of the essential part showing different conventional examples. In the drawing, 11 is an inner box, 12 is a cooking chamber, 14 is a rotating dish, 15 is a lower heater, 17 is a magnetron, 18 is a reflector, 19 is an upper heater, 20 is a heater through hole, 23, 25 and 26 are It is a high frequency reflector.

Claims (1)

(57) [Claims] 1. A heating apparatus comprising: a magnetron for heating a cooking object in a heating cooking chamber with high frequency; A high-frequency cooking apparatus with a heater, characterized in that a high-frequency reflector is provided near a heater through-hole in a room so as to be near the upper side of the upper heater.