KR20000011118U - Anode Wall Structure of Microwave Oscillation Tube for Microwave Oven - Google Patents

Abstract

The present invention relates to the anode wall structure of the microwave oven for microwave oven, in particular, the anode wall 61 of Cu material having a thickness of 0.35mm is coupled to the anode 60 to dissipate the reduced electron beam, the anode wall (61) The holder 62 made of Mo material having a thickness of 1.0 mm while being bonded to the bottom surface is arranged in contact with the second grid 100, so that the coefficient of thermal expansion according to the thickness ratio at the joint can be made constant. This prevents thermal deformation between the holder 62 and the second grid 100, thereby preventing short circuits between the grids and preventing the holder 62 from being struck down to cause interference with high frequency generation. .

Description

Anode wall of microwave generater for microwave oven

The present invention relates to an ultra-high frequency oscillator for a microwave oven, and more particularly to the wall structure of the anode.

The microwave oven uses a magnetron driven by a high voltage of 4KV as an ultra-high frequency oscillator. This magnetron is a kind of bipolar vacuum tube that generates microwaves, the structure of which is shown in FIG.

That is, as shown in FIG. 1, the magnetron is provided with a power input unit, a heater, an input cavity and an output cavity, and a feedback rod in a filter box covered with a lower portion thereof, and an antenna in the anode is installed in a bracket. The inside of the filter box and the antenna part of the anode are designed to maintain a vacuum.

Here, the cathode is disposed on the upper surface of the heater to be heated to a high temperature as the heater generates heat to emit hot electrons.

The input cavity is a space surrounded by a cathode, a first grid, and a choke structure. The cathode is a ring-shaped disk having a hole formed in the center thereof, and the first grid disposed at regular intervals on the top of the cathode is applied with a bias voltage. Electrons emitted from the cathode are controlled and connected to the input cavity.

At this time, the first grid and the cathode are electrically insulated, that is, the direct current must be shielded, and the surface current forming the microwaves inside the input cavity must be energized. For this purpose, the choke structure is disposed between the cathode and the first grid. do.

On the other hand, the output cavity disposed on the upper part of the input cavity is installed so as to face the upper part of the first grid of the input cavity, the electrons passing through the first grid must pass through / so that the choke structure is between the cathode and the first grid for this purpose Is placed on.

On the other hand, the output cavity disposed in the upper portion of the input cavity is installed so as to face the upper portion of the first grid of the input cavity, the second grid that the surface current is induced while electrons passing through the first grid and protrudes downward from the bottom surface It refers to the space surrounded by the anode and the wall formed with the projection. In this space, electrons focused on the input cavity are densely modulated, accelerated by the potential difference between the first and second grids, and microwaves are formed by the surface current induced in the second grid. A plurality of cooling fins are stacked on the anode for dissipating the decelerated electron beam to radiate heat.

The first and second grids are made of metal and have the same shape as the cathodes corresponding to the cathodes, and a plurality of slots cut in the radial direction from the center are formed at predetermined intervals along the circumferential direction.

Therefore, the electrons connected to the input cavity are densely modulated by the automatic shielding function of the bias power of the first grid to pass through the first grid, and when an operating voltage is applied between the input and output cavities that are insulated from each other, a potential difference is generated therebetween. As a result, electrons passing through the first grid are accelerated to pass through the second grid so that surface current flows through the output cavity.

As a result, microwaves are formed in the output cavity, which passes through the center of the anode and radiates through an antenna provided in the output cavity. For this purpose, the antenna coupling end is located in the output cavity.

Meanwhile, a feedback rod for feeding back a part of the microwaves formed in the output cavity to the input cavity is installed at the center between the input and output cavities to amplify and resonate the power of the microwave.

In the magnetron as described above, the anode wall is made of Cu material, and a holder of Mo material bonded to the lower surface of the anode wall is disposed on the second grid.

However, when the thickness of the anode wall is 0.1mm, since the thickness of the holder is 1.0mm, the junction temperature between the holder and the anode wall is 700 ° C. during high temperature operation, so that the holder sags downward due to the difference in thermal expansion of both members, and thus it is difficult to generate high frequency. There has been a problem that the second grid disposed below the drooping holder and the first grid disposed below may be shorted with each other while maintaining a predetermined gap therebetween.

In addition, even when the thickness of the anode wall is 1.0 mm, the above-described problem occurs because the amount of expansion of the wall is very large and the deformation amount of the holder is large.

Therefore, the present invention was devised to solve the problems of the anode wall of the conventional magnetron, and provides an anode wall structure that enables high frequency generation by reducing the amount of thermal strain and prevents short circuit between the first and second grids. Its purpose is to.

The present invention for achieving the object as described above is characterized in that the thickness of the anode wall of Cu material bonded to the holder of Mo material having a thickness of 1.0mm disposed on the second grid is 0.35mm.

Therefore, the present invention can make the coefficient of thermal expansion constant according to the thickness ratio at the junction between the anode wall and the holder to prevent thermal deformation between the holder and the second grid, and to prevent short circuit between the first and second grids. Will be.

1 is a cross-sectional view of a conventional microwave oven for microwave oven,

2 is an enlarged view of a portion “A” of FIG. 1;

3 is a schematic view showing the structure of the adduct wall according to the present invention.

Explanation of symbols on the main parts of the drawings

10: power input unit 20: heater

30: input cavity 40: output cavity

50: feedback rod 60: anode

61: anode wall 62: holder

70: antenna 80: cathode

90: first grid 100: second grid

110: choke structure

Hereinafter, the structure of the cathode 80 of the ultra-high frequency oscillator according to the present invention will be described in detail with reference to the accompanying drawings.

Ultra-high frequency oscillator according to the present invention, as shown in Figure 1, the power input unit 10, the heater 20, the input cavity 30 and the output cavity 40, the feedback back in the filter box covered with a lower cover The rod 50 is installed, and the antenna 70 in the anode 60 is installed in the bracket. The inside of the filter box and the antenna 70 of the anode are designed to maintain a vacuum.

Here, the cathode 80 is disposed on the upper surface of the heater 20 to be heated to a high temperature as the heater 20 generates heat to emit hot electrons.

The cathode 80 is formed by stacking a plurality of plates in sequence.

The input cavity 30 is a space surrounded by the cathode 80, the first grid 90, and the choke structure 110, and the cathode 80 has a multi-layered shape with a ring having a hole formed in the center thereof. The first grid 90 disposed at regular intervals above the cathode 80 is applied with a bias voltage to control and connect electrons emitted from the cathode 80 to the input cavity 30.

In this case, the first grid 90 and the cathode 80 are electrically insulated, that is, the direct current must be shielded, and the surface current forming the microwaves in the input cavity 30 must be energized. 110 is disposed between the cathode 80 and the first grid 90.

Meanwhile, the output cavity 40 disposed above the input cavity 30 is installed to face the upper portion of the first grid 90 of the input cavity 30 so that electrons passing through the first grid 90 pass through the surface. It refers to a space surrounded by the second grid 100, from which current is induced, and an anode on which protrusions projecting downward from the bottom surface are formed. In this space, the electrons focused on the input cavity 30 are densely modulated and accelerated by the potential difference between the first grid 90 and the second grid 100, and by the surface current induced in the second grid 100. Microwaves are formed. A plurality of cooling fins are stacked in the anode 60 to dissipate the reduced electron beam to radiate heat.

The anode 60 forming the output cavity 40 is provided with a wall 61 made of Cu, and a holder 62 made of Mo is bonded to the bottom surface of the wall 61. The lower surface of the holder 62 is in contact with the second grid 100.

Here, since the thickness of the anode wall 61 has a thickness of 0.35mm for the case where the thickness of the holder is 1.0mm, the coefficient of thermal expansion according to the thickness ratio of the holder 62 and the anode wall 61 at the junction of 700 ° C or more. A ratio can be made constant, and the thermal deformation of the holder 62 and the 2nd grid 100 arrange | positioned under this holder 62 can be prevented.

The first grid 90 and the second grid are made of metal and have the same shape as the cathode 80 corresponding to the cathode 80, and a plurality of slots cut along the circumferential direction at a center are predetermined distances along the circumferential direction. Formed.

Therefore, the electrons connected to the input cavity 30 are densely modulated by the automatic shielding function of the bias power supply of the first grid 90 to pass through the first grid 90, where the input and output cavities 30 and 40 are insulated from each other. When an operating voltage is applied therebetween, a potential difference is generated therebetween, and electrons passing through the first grid 90 are accelerated to pass through the second grid 100 so that a surface current flows in the output cavity 40.

As a result, microwaves are formed in the output cavity 40 and the microwaves penetrate through the center of the anode and are radiated through an antenna provided in the output cavity 40. To this end, the antenna coupling end is located in the output cavity 40.

On the other hand, in the center between the input and output cavities 30 and 40, a feedback rod 50 for feeding back part of the microwave formed in the output cavity 40 to the input cavity 30 is installed to amplify and resonate the power of the microwave .

As described above, the ultra-high frequency oscillation device of the present invention can make the coefficient of thermal expansion constant according to the thickness ratio at the junction of the anode wall and the holder to prevent the thermal deformation of the holder and the second grid, thereby preventing the first and second grids. The short circuit in between can be prevented, and an effect which can prevent the holder from being struck down and causing an interference with high frequency generation can be obtained.

Claims (1)

A power source input unit 10, a heater 20 for generating heat by receiving power from the power source input unit 10, a cathode 80 disposed adjacent to the heater 20, and a cathode disposed adjacent to the cathode 80; An input cavity 30 which is surrounded by a first grid 90, a choke structure provided between the cathode 80 and the first grid 90, and a second grid provided on the anode and the first grid 90 ( Part of the microwave formed in the output cavity 40 is installed between the output cavity 40 surrounded by the 100, the radiating means for radiating the microwave formed in the output cavity 40 and the input and output cavity (30, 40) In the microwave microwave tube including a feedback means for feeding back to the input cavity 30, An anode wall 61 made of Cu material having a thickness of 0.35 mm coupled to the anode 60 is coupled, and a holder 62 made of Mo material having a thickness of 1.0 mm is bonded to the bottom surface of the anode wall 61. An anode wall structure of the microwave oven for microwave oven, characterized in that disposed in contact with the second grid (100).