JPH0266866A - High frequency heating device - Google Patents

Abstract

PURPOSE:To stabilize the cutoff characteristic of electric waves used, by covering the surface of a drainer with conductive film. CONSTITUTION:A turntable 7 on which a placing table 6 is borne is rotated by a motor 8 through a metal shaft 14. A choke part 9 having a cutoff characteristic for the electric waves used is furnished in the neighborhood of this shaft 14. Opening 16 in this choke part 9 faces the shaft 14. Silicon rubber, etc., is inserted to the shaft 15 of the motor 8 so that split broth does not intrude to inside of the motor 8 along the shaft 15, and also a drainer 10 is provided, which is equipped with a fitting part 17 in contact with the shaft 14 and a bevel-shaped conical part 18. This drainer 10 is covered with conductive film 13 so as to contact the shaft 14, which involves provision of conductive material confronting the opening of the choke part. Accordingly the cutoff characteristics for the electric waves used are stabilized, even though the bottom position of a heating chamber fluctuates up and down, without requiring enlargement of the outside dimension of the product as in conventional arrangement.

Description

[Detailed Description of the Invention] Industrial Field of Application The present invention provides a turntable 2 on the lower surface of a heating chamber. It relates to a configuration that contributes to the stability of the blocking characteristics.

2. Description of the Related Art Conventional high-frequency heating devices, such as those shown in FIGS. 3, 4, and 5, include a heating chamber 1 in the main body, a high-frequency oscillator (magnetron) 2, and a high-voltage transmitter to send high-frequency waves to the heating chamber 1. There are a power transformer 3 that forms the circuit, a fan motor 4 that cools these power supply components, and the like. Inside the heating chamber 1, there is a mounting table 6 on which an object to be heated 5 is placed. The mounting table 6 is pivotally supported by a turntable 7 and rotates. The turntable 7 penetrates from the bottom surface of the heating chamber 1 to the outside, and the shaft portion 14 of the turntable 7 is inserted into the shaft portion 15 of the motor 8 to rotate. The radio waves used (2
A choke part 9 having a blocking characteristic against 450MH2) is fixed.

The opening 16 of the choke part 9 is connected to the shaft part 1 of the turntable 7.
It is located facing 4. The dimension D that the shaft section 14 of the turntable 7 passes through the bottom of the heating chamber 1, and the dimensions of each part of the choke section 9, such as the opening dimension W, the thickness dimension h, and the depth dimension, are determined experimentally as follows. .

The frequency of the radio waves used is 245ONHz D=12mrn w 1-8.5mm w2 = 2.5mm h
= 14 mm L = 35 mm In addition, to prevent spilled broth from the shaft 14 of the turntable 7 to the outside of the heating chamber 1, which is transmitted through the shaft 15 of the motor 8 as shown by the arrow, and from entering the inside of the motor 8, The fitting part 1 is made of a material such as, and is inserted into the shaft part 15 of the motor 8 and contacts the shaft part 14 of the turntable 7.
A drainer 10 having a cone 7 and an umbrella-shaped conical part 18 is provided. The dimensions of the colander 10 will be described. It is inserted into the shaft part 15 of the motor 8 and the shaft part 1 of the turntable 7.
Regarding the dimension P of the fitting part 17 in contact with 4 and the gap dimension Q between the umbrella-shaped conical part 18 and the motor mounting plate 11 to which the motor 8 is attached, P - 10 mm G = 5 mm or more The umbrella-shaped conical part 18 of the drainer 10 As shown by the arrow, the boiling liquid that has been transmitted to the
Do not allow the boiling liquid to enter the motor 8 (and fall to the bottom).

Problems to be Solved by the Invention However, in such a high-frequency heating device shown in FIG.
In mass production, the bottom of the heating chamber 1 moves upward or downward as shown by the dotted line, and the common dimension of the shaft of the turntable 7 becomes inconsistent, causing the opening aN of the choke section 9 to change.
The positional relationship between this and the shaft portion of the turntable 7 will vary. In this case, the shaft portion of the turntable 7 becomes a conductive portion penetrating through the heating chamber 1, and becomes an antenna. Then, the choke part 9 deviates from the blocking characteristics of the used radio waves, and the amount of radio wave leakage increases, sometimes even exceeding the legal amount.

In addition, as a countermeasure to these problems, it is possible to increase the size of the shaft of the turntable 7. Either reduce the dimension P of the section, or lower the motor mounting plate 11 further downwards to reduce the dimension R (Fig. 4).
All you have to do is make it smaller. However, the dimension P of the fitting part of the drainer 10 becomes smaller and the fitting force with the shaft of the motor 8 weakens, causing the drainer 10 to fall downward when the device is used. The motor 8 even locked up. Furthermore, if the motor mounting plate 11 is lowered further to reduce the dimension R, the motor 8 will come into contact with the bottom plate 12, which will require increasing the external dimensions of the product, which will significantly increase the cost. .

Therefore, it has been impossible to economically mass-produce the choke part 9 and to obtain stable blocking characteristics for the radio waves used.

Means for Solving the Problems In order to achieve the above object, the high frequency heating device of the present invention includes:
A main body, a heating chamber inside the main body, a door pivotally supported on the front side of the heating chamber so that it can be opened and closed freely, a mounting table on which the object to be heated is placed, and a mounting table that rotatably supports the mounting table and is attached to the outside of the heating chamber. a turntable motor, a turntable having a conductive shaft s for mounting and supporting a mounting base and connecting it to the motor, a fitting part inserted into the motor shaft and in contact with the turntable shaft part, and an umbrella-shaped cone. The drainer has a conductive film on the surface of the drainer, and has a choke part that exhibits blocking properties against radio waves used and is located near where the turntable shaft passes from the heating chamber to the outside. It is a covered structure.

Function: The high-frequency heating device of the present invention ensures that the conductive parts of the metal shaft of the turntable and the conductive cover of the drainer always face the opening of the choke part even if the positions are varied vertically during mass production. This has the effect that it can be mass-produced economically and the stability of the blocking characteristics of the radio waves used can be determined.

Practical Example Hereinafter, an example of the present invention will be explained based on the drawings.
-7 Explain. The same numbers as in the conventional example are given.

FIG. 1 is an enlarged sectional view of a state in which an object to be heated 5 is mounted and supported on a mounting table 6 inside a heating chamber (1). The mounting table 6 is pivotally supported by a turntable 7 and rotates. The turntable 7 penetrates from the bottom of the heating chamber 1 to the outside, and the metal shaft portion 14 of the turntable 7 is inserted into the shaft portion 15 of the motor 8 and rotated. A choke part 9 having a blocking property against radio waves used (2450 MHz) is fixed to the bottom part of the heating chamber 1 near where the shaft part 14 of the turntable 7 penetrates from the bottom of the heating chamber 1 to the outside. The opening 16 of the choke part 9 is connected to the shaft part 14 of the turntable 7.
It is located facing the. The dimension D where the shaft portion 14 of the turntable 7 passes through the bottom of the heating chamber 1, the dimensions of each part of the choke portion 9, the opening dimension W, the thickness dimension h, and the depth dimension are as described in the conventional example, D- 12mmw1=8.5mm w2=2.5mmh=
14mm L=35mm In addition, the spilled broth flows from the shaft 14 of the turntable 7 to the outside of the heating chamber 1, as shown by the arrow, and the shaft 15 of the motor 8.
The fitting part 17 and the umbrella-shaped conical part 18 are inserted into the shaft part 15 of the motor 8 and in contact with the shaft part 14 of the turntable 7. A colander 1o with a holder is provided. In contact with the metal shaft portion 14 of the turntable 7,
The drainer 10 is covered with a conductive film (deposited metal film) 13. In addition, this conductive film (evaporated metallic film)
It goes without saying that instead of 13, a separate cover may be made of aluminum material and covered.

The dimensions of the colander 10 are as shown in the conventional example, P-10 mm Q=5 mm or more. Therefore, the broth that has reached the umbrella-shaped conical portion 18 of the colander 1o is directed to the motor mounting plate as shown by the arrow. 11 protruding holes 1
Do not allow the boiling liquid to enter the motor 8 from 2 (and fall to the bottom).

Effects of the Invention 9 F1) As described above, according to the high frequency heating device of the present invention, the following effects can be obtained.

(1) Since the boiling liquid that enters from the shaft of the turntable at the bottom of the heating chamber does not enter the motor and falls outside the heating chamber, safety is sufficiently ensured.

(2) Even if the bottom plate of the heating chamber is mass-produced and the position is uneven up and down, the conductive film (vapor-deposited metal film) of the colander is in contact with the shaft of the turntable, so the opening of the choke part Since there is always a metal material or conductive film (vapor-deposited metal film) on the opposing side, the choke part will not have the blocking characteristics for the radio waves used even if it is mass-produced without increasing the external dimensions of the product. You will become financially stable.

[Brief explanation of the drawing]

FIG. 1 is an enlarged cross-sectional view of the bottom of a heating chamber according to an embodiment of the present invention, FIGS. 2(a) and (b) are exploded perspective views of the same essential parts, and FIG. 3 is a general FIG. 4 is a cross-sectional view of the conventional high-frequency heating device, and FIG. 5 is an enlarged cross-sectional view of the main parts thereof. 1... Heating chamber, 2... High frequency oscillator (Magneto 10/\-/Ron), 3... Source T-lance, 4...
Fan motor, 5... Heated object, 6... Placement table, 7... Turntable, 8...
Motor, 9...Choke part, 10...Drainer part, 11...Motor mounting plate, 12...
Extrusion hole, 13... Conductive film (vapor deposited metal film), 14... Shaft portion, 15... Shaft portion, 16
...... Opening part, 17... Fitting part, 1B.
・・・・・・Umbrella-shaped conical part.

Claims (1)

[Claims] a main body, a heating chamber within the main body, a door pivotably supported on the front surface of the heating chamber so as to be openable and closable, a mounting table on which the object to be heated is placed, and a mounting table that rotatably supports the mounting table and is placed outside the heating chamber. an attached turntable motor, a turntable having a conductive shaft portion for mounting and supporting the mounting base and connecting the motor to the motor; and a fitting that is inserted into the shaft of the motor and contacts the turntable shaft portion. and a choke part that exhibits a blocking characteristic against radio waves used and is provided near the point where the turntable shaft part penetrates from the heating chamber to the outside, A high-frequency heating device configured to cover the surface with a conductive film.