KR100252315B1 - Choke assembly of a magnetron - Google Patents

Abstract

PURPOSE: A choke assembly for a magnetron is provided to prevent a welding trouble as the brazing weld of the choke assembly by restraining a constituent of high frequency in magnetron. CONSTITUTION: The first choke(31) consists of a drum. The second choke(32) is separated at the outside of the first choke(31) in a predetermined space. A flange part(31a) is formed along to the upper end of the first choke(31) by melting of a washer(33) which is positioned at the upper of the first choke(31). A stepped part(50) is formed at the end of the flange part(31a) of the first choke(31). A groove is formed at the boundary of an upper shield cup(15). A braze material is received in the first choke(31) as the brazing weld of the choke assembly. An over diffusion preventing means of the braze material is prepared at the first choke(31) in order to prevent an over diffusion of the braze material.

Description

Choke Assembly of Magnetron

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetron for a microwave oven, and more particularly to a choke assembly of a magnetron used to suppress harmonic components generated during the oscillation operation of the magnetron in a microwave oven.

In general, as shown in FIG. 1, a magnetron for a microwave oven has a plurality of vanes 2 radially assembled on an inner wall of a cylindrical anode body 1, and is formed on the upper and lower portions of the vanes 2. The annular inner strap 3 and the outer strap 4 are electrically and mechanically fixed to the step grooves.

An antenna 5 is connected to one vane of the plurality of vanes 2 to draw energy of high frequency generated inside the anode body 1 to the outside, and has a funnel shape at the upper and lower openings of the anode body 1. The first and second magnetic pole pieces 6 and 7 for magnetic field convergence are arranged to face each other.

On both sides of the positive electrode body 1, the filament 8, which is a negative electrode, is fixed to the upper end shield 9 and the lower lower shield 10 by the upper end shield, and the upper end shield 9 and The lower shield 10 is supported and fixed by a metal center lead 11 and a side lead 12, and at the bottom of the center lead 11 and the side lead 12, a cathode ceramic 13 and an electrical input terminal are provided. The in terminal terminal 14 is provided.

The upper and lower portions of the anode body 1 are fixed to the upper shield cup 15 and the lower shield cup 16, and the upper shield cup 15 has an antenna ceramic 17 and an exhaust pipe 18. The other end of the antenna 5 is connected to the exhaust pipe 18.

A plurality of heat dissipation fins 19 are disposed on the outer circumferential portion of the cathode body 1, and the other end of the heat dissipation fins 19 is mechanically coupled to the lower yoke 20 having the exhaust hole, and the lower yoke 20 is provided. Near the top of the upper yoke 21 is coupled by a bolt.

A ring-shaped permanent magnet 22 is disposed on the outer circumferential portion of the upper shield cup 15 between the upper yoke 21 and the upper end of the positive electrode body 1, and the lower yoke 20 and the lower end of the positive electrode body 1 are disposed. A ring-shaped permanent magnet 23 is also disposed on the outer circumferential portion of the lower shield cup 16 therebetween.

In the drawings, reference numerals 24 and 25 denote choke coils and filter cases forming an input stage filter unit which serves to apply power to the cathode and prevent unwanted high frequency flowing in reverse.

In the magnetron of a general microwave oven configured as described above, when a predetermined electric energy is supplied to the terminal 14 electrically connected to the center lead 11 and the side lead 12, the filament 8 generates heat and heat electrons. Will emit.

The radiated hot electrons are the direct current high voltage applied between the filament 8 and the vane 2 and the permanent magnets 22 and 23 disposed on the outer surfaces of the upper shield cup 15 and the lower shield cup 16. By the influence of the constant magnetic flux distribution formed in the working space by the acceleration and rotation in the working space.

The hot electrons accelerated and rotated in this way, when the phase speed of the high frequency electric field between the vanes and the vanes are synchronized with the rotational speed of the electrons, the energy of the electrons is moved into the high frequency electric field and converted into micro energy. It is radiated into the cavity of the microwave oven to heat food.

At this time, a high frequency electric field is formed between the vanes 2 arranged radially on the anode body 1, and particularly, at the end of the vanes 2 closer to the filament 8, the gap between adjacent vanes is narrower, so that a high frequency is generated. An electric field is formed.

On the other hand, during the oscillation operation of the magnetron as described above, an integer multiple of harmonics other than 2.45 [GHZ] is generated. In order to suppress such harmonic components, as shown in the drawing, the choke assembly is provided on the inner upper end of the upper shield cup 15. Is composed.

This choke assembly of the magnetron is shown in FIG. 2, whereby the choke assembly of the magnetron is positioned with a cylindrical first choke 31 and at a constant distance outside the first choke 31. Is composed of a cylindrical second choke 32.

The flange portion 31a of the first choke 31 and the upper end of the second choke 31 are brazed and welded to the upper shield cup 15 by melting the washer 33 during the manufacturing process of the magnetron. The molten braze material penetrates between the upper shield cup 15 and the flange portion 31a of the first choke 31 and the second choke 32 by capillary action.

However, according to the conventional choke assembly of the magnetron configured as described above, since the choke assembly is not provided with any means for preventing excessive diffusion of the braze material spread by the capillary phenomenon, the portion where the braze material is required during brazing welding of the choke assembly is required. There was a problem causing brazing defects while spreading to other parts.

In more detail, the end of the flange portion to be actually welded is not welded due to excessive diffusion of the braze material, resulting in poor assembly, and deterioration of harmonic suppression efficiency due to such poor assembly could not be avoided.

Therefore, the technical problem to be achieved by the present invention, that is, the object of the present invention, to solve the above problems of the choke assembly of the conventional magnetron, a magnetron that can prevent a welding defect during brazing welding of the choke assembly To provide a choke assembly.

1 is a longitudinal sectional view showing a structure of a magnetron for a typical microwave oven.

Figure 2 is a cross-sectional view showing the structure of a choke assembly of a conventional magnetron.

Figure 3 is a cross-sectional view showing the structure of the choke assembly of the magnetron according to the present invention.

Explanation of symbols on the main parts of the drawings

One; Anode body 2; Bain

5; Antenna 8; filament

15; Upper shield cup 31; First choke

31a; Flange portion 32; 2nd choke

33; Washer 50; Step

The object of the present invention as described above is a cylindrical first choke, which is located inside the upper shield cup and is brazed and welded to a washer on the upper portion thereof, and a second choke, which is arranged at regular intervals outside the first choke. In the choke assembly having a magnetron according to the present invention, the first choke is provided with a braze material overdiffusion preventing means for preventing excessive diffusion of the braze material by receiving molten braze material during brazing welding of the choke assembly. Is achieved by providing a choke assembly of. Here, the said braze material overdiffusion prevention means is a step part formed in the edge part of the flange part of a said 1st choke so that a molten braze material may gather and collect.

According to the choke assembly of the magnetron according to the present invention, the braze material is formed at the boundary with the upper shield cup by the step formed in the flange portion of the first choke, the braze material is formed during the brazing welding of the choke assembly, The ash does not flow down or spread throughout the flange.

Therefore, since the portion to be brazed welded in the choke assembly is correctly welded, poor assembly of the choke assembly can be prevented in advance, and a lowering of harmonic suppression efficiency that can be caused thereby can be prevented in advance.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 shows a choke assembly of a magnetron according to the invention, and according to FIG. 3 shows a basic configuration of the choke assembly of the magnetron according to the invention, namely a cylindrical first choke 31 and this first choke ( The basic configuration of the choke assembly composed of the second chokes 32 provided at a constant interval outside of 31) is the same as that of the conventional choke assembly.

In addition, the first choke (31) is the same as the case of the conventional choke assembly in which the flange portion (31a) formed along its upper circumference is installed by brazing welding by melting of the washer (33) located thereon. However, in the present invention, a predetermined step 50 is formed at the end of the flange portion 31a of the first choke 31 so that a groove is formed at the boundary with the upper shield cup 15. The two are different.

In other words, in the prior art, the braze material flows downward or spreads to the entire surface of the flange portion during brazing welding of the first choke, resulting in incomplete brazing. The braze material gathers and accumulates in the groove to be formed so that the part of the choke assembly to be actually welded can be welded correctly. Therefore, the incomplete brazing phenomenon of the choke assembly as in the related art can be prevented.

As described above, the choke assembly of the magnetron according to the present invention has a groove portion in which a braze material may be collected and accumulated at the boundary with the upper shield cup by a step formed in the flange portion of the first choke during brazing welding of the choke assembly. The braze material does not flow down or spread throughout the flange.

Therefore, since the portion to be brazed welded in the choke assembly is correctly welded, poor assembly can be prevented in advance, thereby reducing the harmonic suppression efficiency that can occur.

Although one embodiment for carrying out the choke assembly of the magnetron according to the present invention has been shown and described above, the present invention is not limited to the above-described embodiment, but deviates from the gist of the present invention as claimed in the following claims. Without this, any person skilled in the art to which the present invention pertains may make various changes.

Claims (2)

A choke assembly having a cylindrical first choke, which is located inside the upper shield cup and is brazed and welded to a washer in the upper portion thereof, and a second choke, which is arranged at regular intervals outside the first choke, The choke assembly of the magnetron is characterized in that the first choke is provided with braze material overdiffusion preventing means for preventing excessive diffusion of the braze material by receiving molten braze material during brazing welding of the choke assembly. The choke assembly of the magnetron according to claim 1, wherein the braze material overdiffusion prevention means is a step portion formed at an end portion of the flange portion of the first choke so that the molten braze material is collected and accumulated.

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