JPH0195490A - High frequency heating device - Google Patents

Abstract

PURPOSE:To make it possible to use a metal container, which has no problems concerning mechanical strength, heat resistance, heat impact resistance, etc., and heat subject matters near the wall of the metal container as well by disposing a heating member with a large dielectric loss around the metal containers for containing the subject matter. CONSTITUTION:A metal container 10 containing subject matters 9 is put on a turn table 7 with its circumference covered with a heating member 12 and a high frequency permeating member 13 of ceramic. Part of high frequency radiated to an oven 1 from a power supply port 3 is absorbed by subject matters 9 in the metal container 10 to be consumed for heat, so the subject matters 9 are heated directly. For the circumference of the container 10, high frequency permeates the high frequency permeating member 13 provided at the sides and bottom of the container 10 to reach the heating member 12 to be absorbed by the heating member 12 of ferrite to be consumed for heat, so the subject matters 9 are heated from the wall sides of the metal container 10 as well. In addition, most of heat from the heating member 12 is transmitted toward the container 10 by the heat insulating effect of the ceramic.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Field of Application) The present invention is applicable to so-called electric ranges such as household high-frequency heating devices and commercial high-frequency heating devices, or to foods, medicines,
The present invention relates to an open-type high-frequency heating device, such as an industrial high-frequency heating device used for heating chemical products, etc., which heats an object by irradiating a high-frequency wave onto the object in an open space.

(Prior Art) In conventional high-frequency heating devices, materials with low diN loss, such as glass, ceramics, plastic, and tetrafluoroethylene resin, are generally used as containers for storing objects to be heated. When a heated object is housed in a container made of a material with low dielectric loss and irradiated with high-frequency waves in the open, the heated object absorbs not only the high-frequency waves irradiated directly to the heated object but also the high-frequency waves that have passed through the container wall. Therefore, the object to be heated can be heated evenly from all directions.

When mechanical strength, heat resistance, thermal shock resistance when local heating occurs, etc. of the container are a problem, a metal container such as stainless steel is used as the container for storing the object to be heated.

(Problems to be Solved by the Invention) As described above, in an open-type high-frequency heating device that heats an object by irradiating the object with high frequency waves in an open space, a glass container is used as a container for storing the object. , pottery,
1ft of plastic, tetrafluoroethylene resin, etc.
Using materials with low loss improves the mechanical strength, heat resistance, and
There is a problem with thermal shock resistance ↑/l when local heating occurs.

In addition, when a metal container is used, the high frequency waves are reflected by the surface of the metal container, so the reflected wave and the incident wave that reached the vicinity of the wall of the metal container overlap each other, causing the heated object near the wall of the metal container to overlap. is not partially heated. Furthermore, metal containers do not transmit high frequencies, so heating cannot be done from the wall side of the metal container. Since the metal container itself is not subjected to high-frequency heating, there are problems with heating, such as preventing the heating of the object to be heated.

An object of the present invention is to provide a high-frequency heating device that uses a metal container and can also heat an object to be heated near the wall surface of the metal container.

(Structure of the Invention) (Means for Solving the Problems) In order to achieve the above problems, the present invention includes the following steps: 1. Heat the object by irradiating the object with high frequency in an open space. This open-type high-frequency heating device is characterized in that a heat-generating member with a large dielectric loss is installed around the outer periphery of a metal container that houses an object to be heated inside the open.

2. It is characterized in that a heat insulating high frequency transmitting member having small dielectric loss, for example, is installed around the outer periphery of the heat generating member.

(Function) When a heat-generating member with a large dielectric loss is attached to the outer periphery of a metal container that stores an object to be heated, the heat-generating member generates heat due to the high frequency irradiated inside the open, so that the object to be heated is removed from the outer periphery of the metal container. It has the effect of enabling heating.

Furthermore, if a high-frequency transmitting material with low dielectric loss is provided around the outer periphery of the heat-generating member, uneven heating due to high-frequency waves irradiated and absorbed by the heat-generating member can be reduced. Note that when ceramic is used as the high-frequency transmitting member, it also has the effect of serving as a heat insulating material, and therefore has the effect of improving heating efficiency during high-frequency heating.

(Example) An example of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a cross-sectional view showing one embodiment of a high-frequency heating device according to the present invention, and FIG. 2 is a cross-sectional view taken along the line A--A in FIG.

Reference numeral 1 in FIGS. 1 and 2 is open, and a power feed port 3 is provided on the ceiling of the open 1, and a waveguide 4 is connected to the power feed port 3. Between the power feed port 3 and the waveguide 4, there is a partition plate 5 made of a material that transmits high frequencies.
is being pinched. The waveguide 4 is connected to a high frequency oscillation 16. A partition plate 5 interposed between the power supply port 3 and the waveguide 4 is provided to prevent steam, oil, juice, etc. generated or scattered during high-frequency heating from going toward the high-frequency oscillator 6. . One of the four side walls of Open 1 is 0P11
It can be opened and closed.

A turntable 7 is provided at the bottom of the open 1, and the turntable 7 is connected to a rotational drive section 8 outside the open 1. The object to be heated 9 is placed on the turntable 7.
A metal container 10 containing a metal container 10 is placed with its outer periphery covered with a ramic material consisting of a heat generating member 12 made of ferrite and a high frequency transmitting member 13.

Next, the operation of one embodiment of the high frequency heating device according to the present invention will be explained. The object to be heated 9 is placed in the metal container 10, and the door 11 is closed.
is opened and placed in the heat generating member 12 made of ferrite on the turntable 7. Close the door 11, operate the rotation drive unit 8 to rotate the turntable 7, operate the high frequency oscillator 6, and apply high frequency (frequency +2450) to the object to be heated 9.
MHz).

The high frequency wave to be irradiated exits the high frequency oscillation 16, passes through the waveguide 4, is transmitted through the partition plate 5, and enters the open 1 from the power feed port 3. A part of the high frequency irradiated into the open 1 is absorbed into the object to be heated 9 in the metal container 310 and consumed as heat, and the object to be heated 9 is directly heated.

In addition, at the outer circumference of the container 10, the high frequency
It passes through the high-frequency transmission member 13 installed on the side and bottom of and reaches the heat generating member 12 .

Here, the high frequency is absorbed by the ferrite which is the heat generating member 12 and consumed as heat, and the object to be heated 9 is also heated from the wall surface of the metal container VS10.

Further, since ceramic is used as the high frequency transmitting member 13 on the outer periphery of the heat generating member 12, most of the heat from the heat generating member 12 is transferred toward the container 10 due to the heat insulating effect of the ceramic. In this way, the object to be heated 9 is not only directly heated by high frequency waves, but also indirectly as the heat generating member 12 installed on the outer periphery of the metal container 10d that houses the object to be heated 9 is heated by high frequency waves. heated.

Next, the effects of one embodiment of the high frequency heating device according to the present invention will be explained. Here, a case in which wet sand is dried will be explained by comparing a conventional example and an embodiment of the present invention. Table 1 shows the implementation conditions, and Table 2 shows the implementation results.

Table 1 Table 2 The same open 1 and the same metal container 10 were used in both the conventional example and the embodiment of the present invention, and the high frequency output was also the same. Further, as the object to be heated 9, river sand moistened under the same conditions was used. In one embodiment of the present invention, ferrite was used as the heat generating member 12 and ceramics was used as the high frequency transmitting member 13.

In the conventional example, a small discharge started to occur after 20 minutes of irradiation with high-frequency waves, so high-frequency irradiation was stopped. Even in one embodiment of the present invention, the high frequency irradiation time is 20 minutes in accordance with the conventional example.
It was set as 1 minute. When the high-frequency irradiation was stopped and the sand in the metal container 10 was taken out, in the case of the conventional example, moisture remained in the area that was in contact with the metal container, but in the case of the embodiment of the present invention, moisture remained uniformly. had been dried. In the case of one embodiment of the present invention, the heat generating member 12 installed outside the metal container 10 absorbed high frequency waves and generated heat, so that an effect was obtained in that the object to be heated near the wall surface of the metal container could also be heated.

Additionally, since there is always a substance that absorbs high frequencies, the effect is that discharge is less likely to occur within the open space. Furthermore, in the case of one embodiment of the present invention, the heat generating member 12
Since the high frequency transmitting member 13 is provided on the outer periphery of the metal container 10, the high frequency waves can pass through the high frequency transmitting member 13 and reach the heat generating member 12 from the turntable side, and the bottom surface of the metal container 10 can be evenly heated. be. If ceramics with heat insulation properties are used as the high-frequency transmitting member 13, the effect of reducing heat loss during heating and improving heating efficiency can be obtained.

In this embodiment, ferrite was used as the heat generating member with large dielectric loss, but other materials such as graphite, carbon, and silicon carbide may also be used.

〔Effect of the invention〕

According to the high frequency heating device of the present invention, a heat generating member with a large dielectric loss is installed around the outer periphery of a metal container that houses an object to be heated, but since this heat generating member also absorbs high frequency waves and generates heat,
The object to be heated can also be heated from the outer peripheral surface of the metal container.

That is, a metal container with no problems in mechanical strength, heat resistance, heat resistance Iff, etc. is used, and the object to be heated near the wall surface of the metal container can also be heated.

In addition, in the high-frequency heating device of the present invention, a high-frequency transmission member with low dielectric loss is installed around the outer periphery of the heat-generating member, and since the high-frequency waves pass through this high-frequency transmission member and reach the heat-generating member, uneven heating can be reduced. is obtained. Furthermore, if a heat insulating ceramic is used as the high frequency transmitting member, the heat loss during heating will be reduced and the heating effect will be improved.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of a high-frequency heating device according to the present invention, and FIG. 2 is a cross-sectional view taken along the line A--A in FIG. 1...Open, 3...Power supply port, 4...Waveguide,
5... Partition plate, 6... High frequency oscillator, 7... Turntable, 8... Rotation drive unit, 9... Heated object,
DESCRIPTION OF SYMBOLS 10... Metal container, 11... Door, 12... Heat generating member, 13... High frequency transmission member. Representative Patent Attorney Nori Chika Ken Shu
First child Marubeni 1st rIA

Claims (1)

[Scope of Claims] 1. In an open-type high-frequency heating device that heats an object to be heated by irradiating the object with high frequency waves in an open space, a dielectric is provided on the outer periphery of a metal container that houses the object to be heated inside the open space. A high-frequency heating device characterized by installing a heat generating member with high loss. 2. The high frequency heating device according to claim 1, characterized in that a high frequency transmitting member with small dielectric loss is installed around the outer periphery of the heat generating member. 3. The high frequency heating device according to claim 1, wherein the high frequency transmitting member is made of heat insulating ceramics.