KR200145959Y1 - A shielder structure of non-harmonics frequency wave of magnetron - Google Patents

Abstract

The present invention relates to a harmonic blocking structure of a magnetron, in which a structure of an output part of the magnetron is changed to prevent leakage of harmonics harmful to the human body generated with microwaves.

Conventionally, by affixing the first and second metal rings having a choke function between a metal tube fixed to the upper end of the anode cylinder and an insulating ring connected thereto, the degree of attenuation at a specific frequency is determined by the capacitance of the choke opening. There is a fatal problem of being harmed by the coupling degree of the structure and antenna, and accordingly the difference in the amount of suppression of harmonics is generated.

Therefore, the choke member installed in the metal tube of the anode part has a structure capable of accurately suppressing cut-off wavelengh, thereby preventing the influence of the choke structure, the coupling degree with the antenna, etc., and significantly reducing the leakage of harmonics. It was attenuated.

Description

Harmonic Block Structure of Magnetron

1 is a diagram illustrating an installation state of a magnetron of a general microwave oven.

2 is a cross-sectional view showing a harmonic blocking structure of a conventional magnetron.

Figure 3 is a cross-sectional view showing a harmonic blocking structure of the magnetron of the embodiment of the present invention.

4 is a cross-sectional view taken along the line A-A of FIG.

* Explanation of symbols for main parts of the drawings

10: anode part 20: metal tube

30: output part 31: insulation ring

40: choke member 41: cylindrical body

42: protrusion

The present invention relates to a harmonic blocking structure of a magnetron, and more particularly, to a harmonic blocking structure of a magnetron, which makes it possible to prevent the leakage of harmonics harmful to the human body generated with microwaves by changing the structure of the output portion of the magnetron.

In general, as shown in FIG. 1, the magnetron M used as a heating source of the microwave generates microwaves having a fundamental wave of about 2450 MHz band through the anode portion, whereas n times of the fundamental wave, that is, an integer multiple of Higher harmonics with frequency are generated at the same time.

When these harmonic components are radiated from the output and propagated together with the fundamental wave through the waveguide into the cavity of the microwave, the harmonic components at this time are too short to be shielded properly in the microwave itself. , The fifth harmonic) leaked badly.

This leakage power not only causes obstacles of wireless communication but also adversely affects the layers that harm the human body, so that the limit of leakage power is regulated by local laws.

In view of the above, efforts have been made to suppress the generation of harmonics in the magnetron itself, and as part of the effort, harmonics leak out of the magnetron using the basic concept of choke having a specific frequency of 1 / 4λ. Research to suppress this is actively being conducted.

On the other hand, in the case of the microwave magnetron currently used, the second harmonic (4900MHz) to the seventh harmonic (7350MHz) is the regulation target or recommendation standard, but the study to suppress the leakage of the harmonics has a relatively large leakage power. In order to suppress the fifth harmonic (12.25 Hz) band from the second harmonic, a method of forming a choke structure having a quarter wavelength for each harmonic is used.

2 shows a conventional harmonic blocking structure using the choke concept, wherein a plurality of vanes 2 are radially arranged and a funnel-shaped magnetic focusing pole piece 3 is fixed to an upper portion of the anode body 1 fixed thereto. The metal pipe 4 is fixed, and the first and second metal rings 5 and 6 having a choke function are joined between the insulating rings 8 connected to the metal pipe and constituting the output unit 7. Configuration.

In the above choke structure, the wavelength of the frequency to be suppressed is composed of a 1/4 lambda value, and the admittance of the portion is set to 0 so as to suppress propagation of the required frequency.

If the frequency is low, the capacitance of the choke opening can be ignored, so the length of the choke is close to 1/4 wavelength without any problem.

However, the higher the frequency, the greater the effect of capacitance, and the choke length is considerably shorter than 1/4 wavelength, and the attenuation of a specific frequency is greatly influenced by the capacitance of the choke opening and the coupling of the structure and antenna. As it was received, there was a fatal problem of leakage of harmonics as a difference occurs in the amount of suppression of harmonics.

The present invention has been devised in view of the above problems of the harmonic blocking structure of the magnetron, and its purpose is to provide a harmonic blocking structure of the magnetron that can broaden the harmonic shielding range.

The present invention for achieving the above object is characterized in that it is possible to shield the leakage power of harmonics by forming a resonant structure of a specific frequency in the choke metal tube to elastically attenuate specific harmonics.

Hereinafter, the harmonic blocking structure of the magnetron of the present invention will be described in detail with reference to the accompanying drawings.

3 is a cross-sectional view showing a harmonic blocking structure according to an embodiment of the present invention, in which a plurality of vanes 11 are arranged radially and both ends of which are fixed by magnetic pole concentrating pole pieces 12 to generate microwaves. The metal pipe 20 is joined to one end surface, and the output part 30 connected to the metal pipe through the insulating ring 31 is connected to the exhaust pipe 33 so that the antenna 32 derived from the vane 11 is connected. This metal ring 34 is provided.

The choke member 40 having a resonance function is fixed to the metal tube 20 and is in contact with the insulating ring 31.

4 is a cross-sectional view showing the choke member, and a plurality of protrusions 42 are formed on the inner circumferential surface of the cylindrical body 41 at regular intervals to constitute a resonator structure having a blocking wavelength.

Therefore, the harmonic blocking device using the resonator structure of the present invention as described above is the resonant frequency (f) Starting from the basic concept of the structure of the resonator, that is, a structure capable of accurately suppressing the cut-off wavelengh in the choke member 40, by the structure of the choke or the coupling with the antenna 32, etc. This can prevent harmonic leakage.

At this time, the blocking wavelength described above can be modified in a myriad of structures depending on the material, length, thickness and position of the choke member 40.

In addition, the harmonic blocking device can be applied to a specific frequency, for example, the second to fifth harmonics, as well as other harmonics and frequencies.

The present invention has the effect of attenuating the leakage of harmonics in a simple way, and also has the advantage of preventing the power consumption by blocking the harmonics to improve the output of the microwave.

Claims (2)

In the magnetron having an output portion 30 which is bonded to one end of the anode portion 10 for generating microwaves and connected to the insulation ring 31 and outputs microwaves, the metal tube 20 The choke member 40 having a resonance function is fixed to the harmonic blocking structure of the magnetron, characterized in that the upper surface of the choke member 40 is in contact with the insulating ring 31. The harmonic blocking structure of a magnetron according to claim 1, wherein the choke member (40) is a cylindrical body (41) having a plurality of protrusions (42) formed at regular intervals.