JPS59189585A - High frequency heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to uniform heating in a high frequency heating device.

Known methods for uniform heating in high-frequency heating devices include a stirrer that diffusely reflects high-frequency waves, a rotating antenna that radiates high-frequency waves, and a method in which a large number of high-frequency supply ports are provided on the peripheral wall of the heating chamber of a tar/table that rotates and moves the object to be heated. . In any case, although the heating unevenness has been reduced to the extent that it can be put to practical use through a number of experiments using Quadr/Todry, it has the disadvantage that it requires one person and a considerable amount of time.

The present invention solves the above-mentioned drawbacks, and aims to provide a high-frequency heating device that achieves uniform heating with simple means.

An embodiment of the present invention will be described below with reference to Fig. 1 and Fig. 2 of the pod. FIG. 1 is a schematic cross-sectional view of a main part showing an embodiment of the high-frequency heating device of the present invention, and FIG. 2 is a top view as seen from the XY direction of FIG. 1. 1 is a high-frequency oscillator that generates high-frequency energy, and 12 is a waveguide that connects the high-frequency oscillator 1 to the heating chamber. The heating chambers 6 and 4 are each made of a metal plate. At the lower part of the heating chamber 6, there is provided a table 5 on which an object to be heated such as food 4 is placed and rotated. Two high-frequency radiation ports 6 and 7 are provided in the part where the waveguide 2 is connected to the heating chamber 6, and one high-frequency radiation port 6 is used as the tip of the waveguide 2 to heat the high-frequency radiation lower part of the power. A partition located near the end of the chamber and separating the above two high frequency radiation holes 6, 70 dimensions B and D from the axial direction of the waveguide 2 and the above two high frequency radiation ports 6°7. The total dimension C of the portion 8 is /C dimension + C→D, which is the pot λ~λ+total λ for the wavelength λ used, and the dimension C of the partition portion 8 is set to be 100 λ or more. 9 This is a screw that connects the lower plate of the FD waveguide 2 and the end of the earthen wall of the heating chamber filter. The dimension E of the mounting part of the screw 9 must be 15 mm or more for ease of manufacture.

The reason why the sum of the dimensions B and D of the high-frequency radiation ports 6 and 70 and the dimension C of the partition portion (B+C) is set to λ˜λ+space λ will be explained. The internal wavelength λgI′i in the waveguide 2 is the wavelength used (
Free space wavelength) λ is also large, and there is a property that it becomes larger as the long side dimension a becomes narrower.

In a waveguide of practical size, at least λg is included in the range of 2X to λ+72. It is known that the magnetic field strength is maximum at the tip of -C1 in the four-wave tube 2, and is also maximum at the position of λg from the tip. Therefore, it goes without saying that the magnetic field strength is at its maximum at the high-frequency radiation port 6 provided at the tip, but the magnetic field strength of the high-frequency radiation lower part can also be at maximum or close to the maximum, so the high-frequency radiation port 6, 7
High frequency energy can be efficiently radiated into the heating chamber S from the heating chamber S.

The dimension C of the partition part 80 is set to be 102 or more, but the wavelength used by the high-frequency heating device is 122 mm (circumference $2.450M).
(corresponding to T-1z), 7 102 is approximately 15 mm. These 15 conditions apply to a household high-frequency heating device called a microwave oven, when the partition part 8 is made of painted iron plate or stainless steel.
This is the minimum dimension necessary to prevent problems such as discoloration and deformation due to abnormal heating in a state where the object to be heated 4 is forgotten to be placed in the heating chamber 6 which supplies high frequency energy of W, i.e. in a dry firing state, and is practical. The dimension C needs to be thicker than the 15mm. Each of the dimensions B and D can be made different in size by moving the position of the dimension C.

Next, the functions and effects of the 16-frequency heating device of the present invention will be explained. The high-frequency energy heading from the high-frequency oscillator 1 to the heating chamber 3 is first radiated into the heating chamber 3 from the high-frequency radiation lower at the lower end of the heating chamber, and then the remaining high-frequency energy is radiated into the high-frequency radiation at the tip of the waveguide 2. It is radiated into the heating chamber 6 through the mouth 6. By adjusting the dimension C and position of the partition part 8, and making the dimension 1 of the high frequency radiation lower and the dimension B of the same 6 different from each other.

The radiation ratio of high frequency energy can be adjusted, and the heating strip f'1
One of the most practical turntables even if the table changes! 1!
It is possible to reduce heating unevenness in the radial direction.

It goes without saying that heating unevenness in the circumferential direction can be reduced by rotating the tar/table 5. Furthermore, it is possible to reduce the heating unevenness in the circumferential direction by rotating the tar/table 5. Furthermore, it is possible to reduce the heating unevenness in the circumferential direction by rotating the tar/table 5. In the case of sake, uneven heating tends to occur in the vertical direction, but the distance A between the tip of the pipe 2 and the side wall of the heating chamber 3
It is possible to reduce heating unevenness in the 10-degree direction by adjusting 1 to prevent the milk or alcohol from being present in the center of the high-frequency radiation L6. To do this, the front plate or high-frequency radiation lower should be placed as close to the end of the heating chamber as possible.

As described above, according to the present invention, one high frequency radiation I'
is the tip of the waveguide, and the other high-frequency radiation L1 is near the end of the heating chamber.The sizes of both high-frequency radiation ports are adjusted to adjust the ratio of high-frequency radiant energy. radial direction.

It is possible to provide a practical high-frequency heating device that reduces heating unevenness in the circumferential direction and the vertical direction of tall objects to be heated, and can reduce the manpower and time required to improve heating unevenness, and the effect of implementing it is amazing. be.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a main part showing one embodiment of the high-frequency heating device 4 of the present invention, and FIG. 2 is a top view as seen from the XY direction of FIG. 1. 1. High frequency oscillator, 2. Waveguide. 3...Heating chamber, 4...Object to be heated. 5 ・Turntable, 6, 7...High frequency radiation port. Applicant: Hitachi Thermal Appliances Co., Ltd.

Claims (1)

[Claims] A high frequency oscillator (1) that generates high frequency energy. In a high-frequency heating device that includes a four-way tube (2) that connects the high-frequency oscillator (1) to a heating chamber (3) and a turntable (5) that rotates the object to be heated (4), a waveguide is used. Two high frequency radiation ports (6) at the joint between the tube (2) and the heating chamber (3). (7), one high frequency radiation port (6) is positioned at the tip of the waveguide (2), and the other high frequency radiation port (7) is located at the tip of the waveguide (2).
is located near the end of the heating chamber (3), and the high-frequency radiation ports (6) and (7) have different sizes.