JPH0935866A - Radiation wave preventing device and high frequency heating device provided with same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation wave preventing device with a magnetic unit preventing a radiation wave easily mountable and to provide a high frequency heating device provided with this radiation wave preventing device. SOLUTION: An electrode part of a through capacitor 23 is protruded from a circumferential surface in the vicinity of the other end of a main unit 22, a terminal is provided 24 (24) in an end part of this protruded part, and leads 27, 27 is respectively connected to both the terminals 24 (24). An engaging frame 4 provided in a case 3, molded with an insulating resin, is externally fitted to the protruded part of the through capacitor 23. In the case 3, joint parts 2a, 2b of the width and thickness equal to both side walls are respectively extended in a lengthwise direction of a storage part 1 from the side walls opposed to a direction orthogonal to the lengthwise direction of the storage part 1 of rectangular parallelepiped shell shape provided with a storage chamber 6 of shape corresponding to magnetic units 15a, 15b stored in this case 3, frame members 4a, 4b, 4c, 4c forming the engaging frame 4 is formed in an end part of both the joint parts 2a, 2b, and the storage part 1 is provided with the first/second storage parts 1a, 1b divided into two parts parallelly with both the side walls from the center of the storage part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation wave preventer for preventing generation of a radiation wave from a magnetron, and a high frequency heater equipped with the radiation wave preventer.

[0002]

2. Description of the Related Art FIG. 5 is a rear view showing a main part of a conventional microwave oven which is an example of a high-frequency heater, and 21 in the figure is a magnetron which oscillates microwaves. Magnetron 21
Is a body 22 that is formed by coaxially stacking cylinders with different diameters.
A flange portion 26 is provided on the upper edge of the main body 22, and the feedthrough capacitor 23 projects from the peripheral surface near the other end of the main body 22. Terminals 24 and 24 are provided at the ends of the feedthrough capacitor 23, and lead wires 27 and 27 are connected to both terminals 24 and 24, respectively.
The flange portion 26 of the magnetron 21 is in contact with the lower surface of the frame 30, and the upper surface of the frame 30 has a rectangular cross section.
A waveguide 28 having a fixed portion 28b protruding from 28a is arranged corresponding to the magnetron 21. The magnetron 21 and the waveguide 28 are fixed to the frame 30 by nuts 32, 32, ... And bolts 31, 31, ... Penetrating the flange portion 26, the frame 30, and the fixing portion 28b.

A cylindrical antenna 25 for radiating microwaves is attached to the body 22 of the magnetron 21, and the antenna 25 penetrates through the frame 30 and the side wall of the waveguide 28 and projects into the inside of the waveguide 28. ing. Then, a high voltage of about 4 kV is applied to the feedthrough capacitor 23 via the lead wires 27, 27 and the terminals 24, 24 to drive the magnetron 21 to drive 30 to 300.
A microwave near MHz is oscillated, and the microwave radiated from the antenna 25 is guided to the heating chamber by the waveguide 28 to heat the object to be heated in the heating chamber.

[0004]

In such a microwave oven, 30 to 300 MHz generated inside the magnetron is generated.
The high frequency wave near z is radiated to the outside through the feedthrough capacitor provided in the magnetron as a transmitting antenna using the lead wire of the feedthrough capacitor and the power cord connected to the lead wire. In order to avoid the influence, it is required to reduce the radiation wave of the above-mentioned frequency.

To meet this requirement, it is conceivable to arrange an annular magnetic body near the feedthrough capacitor and insert a lead wire through the annular magnetic body. By this, 30-30
Radiant waves near 0 MHz can be attenuated by 10 dB or more. However, when arranging the magnetic body near the high-power magnetron, it must be fixed so that the magnetic body does not move due to the magnetic field generated by the magnetron.
When the magnetic body moves toward the magnetron due to the magnetic field, the magnetic body may come into contact with the terminal provided on the feedthrough capacitor and the frame in the vicinity of the terminal to cause a short circuit. On the other hand, when moving in the opposite direction, the attenuation of the radiated wave is reduced.

The ring-shaped magnetic body can be fixed by attaching the ring-shaped magnetic body to the frame by using a fixing tool, which is achieved by interposing an insulating material between the frame and the ring-shaped magnetic body and by the fixing tool. There is a problem that the work is complicated because there is work such as mounting on the frame.

The present invention has been made in view of such circumstances, and an object thereof is to prevent a radiant wave by holding a magnetic body at an appropriate distance from a magnetron by an insulating case. It is an object of the present invention to provide a radiant wave protector to which a body can be easily attached and a high-frequency heater equipped with the radiant wave protector.

[0008]

A radiation wave preventer according to a first aspect of the present invention is a radiation wave preventer for preventing generation of a radiation wave by inserting a lead wire for feeding a magnetron into a cylindrical magnetic body. Equipped with an insulating case to store the magnetic body,
The case is characterized in that the stored magnetic body is held at a position separated from the magnetron by an appropriate distance.

Even if the magnetic field generated by the magnetron acts on the magnetic material, the movement of the magnetic material is blocked by the case containing the magnetic material. Further, since the case is insulative, it is not necessary to newly install an insulating material, and the mounting work is easy.

A radiation wave preventer according to a second aspect of the present invention is the radiation wave preventer according to the first aspect of the present invention, wherein the case includes a storage portion for storing a magnetic material.
It is characterized by comprising an engaging portion that engages with the magnetron, and a joint portion that connects the engaging portion and the storage portion.

Since the case can be attached by engaging the engaging portion with the magnetron, the attaching operation is easy. In addition, since the storage part for storing the magnetic material is appropriately separated from the magnetron to which a high voltage is applied by the joint part, the danger of short circuit between the magnetic material and the magnetron is prevented, and the radiation wave is attenuated. The magnetic substance can be held at a position with a high rate. Further, since the magnetic body is stored in the storage part of the insulating case, short-circuit between the surrounding members around which the magnetic body is arranged and the magnetic body is prevented.

The radiation wave preventer according to the third aspect of the invention is connected to an electrode portion projecting from the magnetron, and a lead wire for feeding the magnetron is inserted into a cylindrical magnetic body to generate a radiation wave. In the radiant wave preventer for preventing, an insulating case for storing the magnetic body is provided, and the case has a storage section for storing the magnetic body, a fitting section to be externally fitted to the electrode section, and the fitting section. It is characterized by including a joint part which connects with the storage part.

Since the case can be attached by externally fitting the engaging part to the electrode part such as a feedthrough capacitor provided on the magnetron, the mounting work is easy, and the electrode part to which a high voltage is applied depends on the case. Protected and safe.

The radiation wave preventer according to a fourth aspect of the present invention is the radiation wave preventer according to any one of the first, second, and third aspects, wherein the magnetic body housed in the case has a plurality of portions divided in the longitudinal direction. Is provided with a pressing member for bringing the respective portions of the magnetic body into contact with each other.

When a plurality of parts divided in the longitudinal direction are brought into contact with each other to form a cylindrical shape, the lead wire can be easily inserted into the magnetic body by wrapping the lead wire in the cylinder. Further, since the respective parts of the magnetic body are in contact with each other by the pressing member, the ability to attenuate the radiated waves is high.

The high-frequency heater according to the fifth aspect of the present invention is the first aspect.
The radiation wave preventer according to any one of claims 1 to 4 is provided.

As a result, it is easy to attach the magnetic body for preventing the radiation wave, and even if the magnetron is operated, the movement of the magnetic body is blocked by the case storing it, and the electrode portion is protected by the case. As a result, the safety is high and the radiation wave attenuating ability of the magnetic material is kept high.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a side sectional view showing a main part of a high-frequency heater according to the present invention, in which reference numeral 40 is a heating chamber. The ceiling of the heating chamber 40 is a frame that supports the waveguide 28.
The frame 30 is in contact with 30, and the frame 30 extends rearward of the heating chamber 40. A waveguide 28 having a rectangular cross section is provided on the frame 30 from slightly behind the heating chamber 40 to approximately the center of the heating chamber 40. The rear end of the waveguide 28 is closed, and the front end of the waveguide 28 is connected around a hole formed in the ceiling of the heating chamber 40.
A magnetron 21 is arranged at the back of the heating chamber 40. The magnetron 21 is provided with a flange portion 26 at one end peripheral edge of a main body 22 formed by coaxially stacking cylinders having different diameters, and the flange portion 26 is screwed to the lower surface of the frame 30.

A cylindrical antenna 25 for radiating microwaves is attached to the center of the upper portion of the main body 22 of the magnetron 21, and the antenna 25 penetrates through the wall surface near the rear end of the frame 30 and the waveguide 28. It projects inside the wave tube 28. Further, from the peripheral surface near the lower end of the main body 22, the feedthrough capacitor 23
The electrode part of is protruding, and the end of this protruding part has a terminal
24 (24) is provided, and the lead wire 2 is connected to both terminals 24 (24).
7 and 27 are connected respectively.

As will be described later, the protruding portion of the feedthrough capacitor 23 is made of a case 3 formed of an insulating resin such as ABS resin.
The engaging frame 4 provided in the is externally fitted. As shown in FIG. 2, magnetic materials 15a 1 and 15b formed by molding ferrite into a semi-cylindrical shape are housed in the case 3.
The case 3 is made cylindrical by the case 3. And
Lead wires 27, 27 connected to the terminal 24 (24) of the feedthrough capacitor 23 are inserted through the inside of the cylindrical portion 15 formed by the case 3 and the magnetic bodies 15a, 15b.

3 and 4 are an exploded perspective view and a side sectional view showing the case 3 described above. The case 3 has a width and a thickness from two side walls facing each other in the direction orthogonal to the longitudinal direction of the rectangular parallelepiped shell-shaped storage unit 1 in which a storage chamber 6 having a shape corresponding to a cylindrical magnetic body to be stored therein is provided. A frame member in which joint portions 2a and 2b, which are the same as those of both side walls, are respectively extended in the longitudinal direction of the storage portion 1 and an engagement frame 4 is formed at the end portions of both joint portions 2a and 2b.
4a, 4b, 4c, 4c are provided, and the storage part 1 is provided with a first storage part 1a and a second storage part 1b which are divided in two from the center thereof in parallel with the both side walls.

A storage chamber 6a for storing a semi-cylindrical magnetic material is provided in the first storage portion 1a, and a joint portion of the first storage portion 1a is provided.
A pressing member 10a is provided at the center of the side wall where the extension 2a extends so as to incline toward the inside of the first body storage portion 1a. First storage
Semicircular cutouts 9a and 9a are provided at the center of the edges of both side walls facing each other in the longitudinal direction of 1a, and the cutouts 9a and 9a oppose each other at right angles to the side walls. In the vicinity of the edges of both side walls, a convex portion 7 having a right-angled triangular cross section,
7, 7, 7 are provided. Also, from the end of the joint 2a,
The frame member 4a is extended to the outside of the case 3 at an acute angle α.
Is provided.

In the second storage section 1b, as in the first storage section 1a, a storage chamber 6b, notches 9b and 9b, and a pressing member 10b are formed, and notches 9b and 9b are provided. On both side walls that are orthogonal to the side wall and face each other, the above-mentioned convex portions 7, 7, 7,
Locking member 8, 8, 8, 8 having a hole in which 7 is fitted
Is provided. Joint part extending from the side wall of the second storage part 1b
2b is bent so as to form an obtuse angle β slightly before the portion of the joint portion 2a extending from the first storage portion 1b that is bent at an acute angle α, and the frame member 4b is provided at a predetermined length ahead thereof. Frame member
It is provided parallel to 4a. Square frame members 4c, 4c each having one side slightly shorter than the length of the side edge portion are provided at right angles to the frame member 4b at both side edge portions of the frame member 4b.

In the case 3 as described above, the semi-cylindrical magnetic bodies 15a and 15b (see FIG. 2) are fitted into the storage chambers 6a and 6b of the first storage portion 1a and the second storage portion 1b, respectively. After that, the lead wires 27, 27 (see FIG. 1) are sandwiched in the magnetic bodies 15a, 15b and the cutout portions 9a, 9a, 9b, 9b and the engagement frame 4, and the convex portion 7 of the first storage portion 1a is inserted. , 7, 7, 7 in the second storage
5b is fitted into the holes of the locking members 8, 8, 8, 8 and the first storage part
The 1a and the second storage section 1b are locked. As a result, the lead wires 27, 27 can be easily inserted into the tubular portion 15 (see FIG. 1) formed by the case 3 and the magnetic bodies 15a, 15b. Further, the semi-cylindrical magnetic bodies 15a and 15b are holding members.
Since they are pressed by 10a and 10b so as to be in close contact with each other and formed into a tubular shape, a high radiation wave attenuation capability is maintained.

Then, the engaging frame 4 formed with the engaging portions 4a, 4b, 4c, 4c is fitted onto the projecting portion of the feedthrough capacitor 23.
As a result, the magnetic substance 15 is generated by the magnetic field of the magnetron 21.
Even if a or 15b is attracted or repelled,
Since the engaging frame 4 contacts the feedthrough capacitor 23 and the case 3 does not move, the magnetic bodies 15a and 15b do not contact the terminals 24 (24) to which a high voltage is applied. Further, since the terminal 24 (24) and the magnetic bodies 15a and 15b are surrounded by the insulating case 3, safety is improved.

Although the engaging frame 4 of the case 3 is fitted onto the feedthrough capacitor 23 of the magnetron 21 in FIG. 1, the present invention is not limited to this, and may be fitted to the body 22 of the magnetron 21. Needless to say, it is okay.

[0027]

As described above in detail, in the first, second, and fifth inventions, the magnetic body is held by the insulating case to prevent the magnetic body from moving due to the magnetic field of the magnetron. Therefore, the magnetic substance can be easily fixed.

In the third and fifth inventions, since the engaging portion is adapted to be externally fitted to the electrode portion to which the lead wire of the magnetron is connected, the engaging portion can be made compact and the case Takes up little space. Further, since the portion to which the lead wire is connected and the high voltage is applied is surrounded by the insulating case, safety is improved.

In the fourth and fifth aspects of the invention, since the case and the magnetic body are composed of a plurality of members, the lead wire can be taken in so as to be sandwiched, and the lead wire can be easily inserted. . Further, since it can be assembled by locking the respective members of the case, the assembling is easy, and the magnetic body is made into a tubular shape by the pressing member in association with the assembling of the case, and the high radiation wave attenuation capability is maintained. Etc.
The present invention has excellent effects.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a main part of a high-frequency heater according to the present invention.

FIG. 2 is a perspective view showing a magnetic body shown in FIG.

FIG. 3 is an exploded perspective view showing a case.

FIG. 4 is a side sectional view showing a case.

FIG. 5 is a rear view showing a main part of a conventional microwave oven.

[Explanation of symbols]

 1a 1st storage part 1b 2nd storage part 2a Joint part 2b Joint part 3 Case 4 Engaging frame 15a Magnetic substance 15b Magnetic substance 21 Magnetron 28 Waveguide 23 Through capacitor 24 Terminal 27 Lead wire

Claims (5)

[Claims] 1. A radiation wave preventer for preventing generation of a radiation wave by inserting a lead wire for feeding a magnetron into a cylindrical magnetic body, comprising an insulating case for storing the magnetic body, the case comprising: A radiant wave preventer characterized in that the stored magnetic body is held at a position that is appropriately separated from the magnetron. 2. The case comprises a storage part for storing a magnetic material, an engagement part for engaging with the magnetron, and a joint part for connecting the engagement part and the storage part. Radiation wave preventer described. 3. A radiation wave preventer, which is connected to an electrode portion projecting from a magnetron and which inserts a lead wire for feeding the magnetron into a cylindrical magnetic body to prevent generation of a radiation wave, An insulating case for storing a magnetic body is provided, and the case includes a storing section for storing the magnetic body, a fitting section externally fitted to the electrode section, and a joint section for connecting the fitting section and the storing section. And a radiant wave preventer. 4. The magnetic body housed in the case has a plurality of parts divided in the longitudinal direction, and the case is provided with a pressing member for bringing the respective parts of the magnetic body into contact with each other. The radiation wave preventer according to 1, 2, or 3. 5. A high frequency heater comprising the radiation wave preventer according to claim 1. Description: