KR200161120Y1 - Magnetron - Google Patents

Abstract

The present invention relates to a magnetron, and a magnetron having a predetermined thickness and generating microwaves by a power of a predetermined voltage provided by a plurality of vanes and filaments formed in a predetermined number, wherein the thickness of each vane is set to the predetermined The magnetron is reduced at a voltage lower than a predetermined voltage provided to the vane and the filament by reducing the predetermined value relative to the thickness, increasing the number of the vanes, and setting the ratio of the distance between the vanes facing the diameter of the filament within a predetermined range. By driving, not only the cost of the structure, the power supply circuit and the insulating circuit material is reduced, but also the safety is improved.

Description

magnetron

The present invention relates to a magnetron for generating microwaves, and more particularly to a magnetron suitable for driving at a low voltage (for example, 2KV).

In general, magnetron generates ultra-high frequency by high voltage from outside, and it is high-frequency of 915MHz that is used for magnetron that generates high frequency of 2450MHz used for medical, microwave, and other heating, industrial heating range, continuous wave radar. The present invention relates to a magnetron used in a microwave oven.

Conventional magnetrons used in the microwave oven have a plurality of (generally, cavity resonators for inducing high frequency components inside the anode body 10 formed in a cylindrical shape by a copper pipe or the like as shown in FIG. 1). The even vanes 13 are arranged at equal intervals in the axial direction, and the anode body 10 and the vanes 13 constitute the anode portion.

In order to change the capacitance to obtain a uniform resonant frequency, the inner side equalization ring 15 and the outer side equalization ring 17 are alternately connected to the vane 13 at upper and lower portions thereof, respectively, on the top end side of the vane 13. The working space 23 is formed on the central axis of the anode body 10 between the tip portions of the plurality of vanes 13 and the filaments 20.

In addition, in the working space 23, a filament 20 formed of a mixture of tungsten (W) and thorium oxide (ThO ₂ ) and wound in a spiral shape is disposed coaxially with the anode body 10. The filament 20 is heated by an operating current provided from the outside to emit hot electrons.

On the other hand, the upper shield hat 25 and the lower shield hat 27 is fixed to both ends of the filament 20 in order to prevent the emitted hot electrons radiate in the direction of the central axis, respectively, of the lower shield hat 27 In the center part, the first filament electrode 30, which is a central support made of molybdenum, is welded and fixed to the lower end of the upper shield hat 25 through a through hole formed in the center part, and the bottom surface of the lower shield hat 27 is made of molybdenum material. 2 filament electrodes 33 are welded together.

Here, the first filament electrode 30 and the second filament electrode 33 are connected to the power supply terminal 37 through a through hole formed in the insulating ceramic 35 supporting and fixing the filament 20 of the magnetron. It is a cathode support electrically connected to the first external connection terminal 40 and the second external connection terminal 43 to supply a current to the filament 20, the first filament electrode 30 penetrates the central axis of the filament 20 While supporting the upper shield hat (25).

In addition, the upper pole piece 45 and the lower pole piece 47 which form a magnetic path at both side openings of the anode body 10 to uniformly form the magnetic flux in the working space 23 between the filament 20 and the vanes 13. ) Is welded and fixed, the upper pole piece 45 and the lower pole piece 47 are funnel-shaped magnetic bodies.

In addition, upper and lower shield cups 50 and lower shield cups 53 are adhered to and welded to upper and lower portions of the upper pole piece 45 and the lower pole piece 47, respectively. In order to seal the inside of the anode body 10 in a vacuum state, upper and lower portions of the shield cup 53 are in contact with and welded to the ceramic ceramic 55 and the insulating ceramic 35.

In addition, a cylindrical antenna ceramic 55 for insulating the antenna cap 57 to be described later is joined to the upper opening end of the upper shield cup 50 constituting the output portion of the magnetron, and an upper end portion of the antenna ceramic 55 is joined. The exhaust pipe 60, which is a copper material, is bonded thereto, and an antenna 63 is provided at an inner central portion of the exhaust plate 60 to output high frequency oscillated in the cavity resonator, and the antenna 63 has vanes 13. Derived from, through the central portion of the upper pole piece 45 extends axially while the end is fixed in the exhaust pipe (60).

In addition, the outer surface of the exhaust pipe 60 protects the welded fixing part of the exhaust pipe 60, prevents sparks generated by electric field concentration, serves as a high frequency antenna, and serves as a window for outputting high frequency to the outside. The antenna ceramic 55 and the antenna cap 57 is covered.

In addition, the upper yoke 60 and the lower yoke 61 are formed on the outside of the positive electrode body 10 to form a magnetic flux in the positive electrode body 10 to connect the returned magnetic flux. Between the 10 and the lower yoke 61, a plurality of aluminum cooling fins 65 are fitted by the clamp member 67 fixed to the anode body 10 and the lower yoke 61, and the magnet A The upper yoke 60 and the lower yoke 61 for forming a path | route together with the 70 and the magnet K 73 are covered.

In the magnetron configured as described above, when an external power source is provided to the first external connection terminal 40 and the second external connection terminal 43 through the power supply terminal 37, the first external connection terminal 40 and the first filament are provided. A closed circuit composed of an electrode 30, an upper shield hat 25, a filament 20, a lower shield hat 27, a second filament electrode 33, and a second external connection terminal 43 is configured to form a filament 20. ) Is supplied with operating current.

Then, the filament 20 is heated by the operating current provided to the filament 20 to emit hot electrons from the filament 20, thereby forming an electron group by the released hot electrons.

At this time, in the working space 23 between the filament 20 and the vane 13 by the driving voltage applied to the second filament electrode 33 and the anode portion (that is, the anode body 10 and the vane 13). A strong electric field is formed, and the magnetic field generated by the magnet A 70 and the magnet K 73 is guided along the lower pole piece 47 toward the working space 23 and the upper pole piece through the working space 23. Proceeding to 45, a high magnetic field is formed in the working space 23.

Therefore, the electron group formed by the hot electrons emitted from the filament 20 into the working space 23 is formed by the strong electric field and the high magnetic field formed in the working space 23 (the anode body 10 and the vane 13). It proceeds while making a spiral rotational movement in the direction, and this movement of the electron group takes place in all the spaces of the working space 23.

At this time, the electron group formed of the hot electrons in accordance with the structural resonance circuit of the vane 13 and the cavity resonator is repeatedly progressed toward the anode part (the anode body 10 and the vane 13) while the heat generated by the collision The silver is transferred along the vanes 13 to the cooling fins 65 disposed on the anode body 10 through the anode body 10 and radiated to the outside, and has a resonance frequency of 2450 MHz corresponding to the speed at which the electron group rotates. High frequencies are induced from the vanes 13.

Then, the high frequency (2450 MHz) induced from the vane 13 is transmitted to the exhaust pipe 60 through the antenna 63, provided to the microwave through the wave guide, and then through the dispersing apparatus. It is provided as a cavity, and the food is cooked by the frictional heat generated when the molecules in the cavity vibrate about 2.4 billion times per second.

Meanwhile, as shown in FIG. 2, a plurality of vanes 13 are formed at equal intervals toward the filament 20 in the cylindrical anode body 10.

Here, the height of the vanes 13 is 9.5mm, the thickness t is 1.85mm, the filament diameter rc is 3.9 ~ 4.0mm, the distance ra between the opposite vanes 13 is formed to 9mm high voltage (For example, 4KV).

However, such a conventional magnetron is driven at a high voltage, so that the structure shape, the cost of the power supply circuit and the insulated circuit material are increased, and the safety is poor due to the noise.

Therefore, the present invention has been devised in view of the above problems, and reduces the thickness of the vanes and increases the number, and the magnetron driven at a low voltage by making the non-plastic range by the distance between the vanes facing the diameter of the filament The purpose is to provide.

In order to achieve the above object, the magnetron according to the present invention has a pre-set firing thickness and a magnetron generating microwaves by a power source of firing voltage provided by a plurality of vanes and filaments formed in the number of firings, wherein each vane The predetermined voltage is reduced to a predetermined value compared to the predetermined predetermined thickness, the number of vanes is increased, and the ratio of the vanes facing the diameter of the filament and the distance between the vanes is set within a plastic range to provide the predetermined voltage to the vanes and the filaments. It is characterized in that it is driven at a lower voltage.

1 is a cross-sectional view showing the structure of a general magnetron,

FIG. 2 is a horizontal cross-sectional view taken along AA of FIG. 1, showing vanes and filaments of a conventional magnetron;

Figure 3 is a horizontal cross-sectional view cut on the basis of AA of Figure 1, showing the vanes and filaments of the magnetron according to the present invention.

* Explanation of symbols for main parts of the drawings

10, 12: bipolar body 13, 14: vane

20, 22: filament 23: working space

25: upper shield hat 27: lower shield hat

45: upper pole piece 47: lower pole piece

60: upper yoke 63: lower yoke

65: cooling fin 70: magnet A

73: magnet K

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

FIG. 3 is a horizontal cross-sectional view taken along AA of FIG. 1 and illustrates vanes and filaments of the magnetron according to the present invention.

Compare the shapes of the vanes 13 in FIG. 2 showing vanes and filaments of conventional magnetrons and the vanes 14 in FIG. 3 showing vanes and filaments of magnetrons according to the present invention. As can be seen, the vanes 14 according to the present invention have a reduced thickness t ', an increased number, and a ratio due to the distance ra' between the vanes 14 facing the diameter rc 'of the filament 22. The filament 22 and the vane 14 are formed to be large.

The operation of the magnetron according to the present invention having the structure as described above will be described in more detail with reference to FIG. 3.

Referring to FIG. 3, the vanes 14 according to the present invention have a thickness t ′ of 1.15 to 1.3 mm, a number N of 12, and a diameter rc ′ of the filament 22. The ratio of the distance ra 'between the vanes 14 facing each other is increased to be 0.500 to 0.513, and is driven at a low voltage (for example, 2 KV).

At this time, (P: output, V: positive voltage, C: capacitance, N: number of vanes, Q: quality factor), where (d is the distance between the vanes) (m: mass of electrons, v: drift speed of electrons), the thickness t 'of the vanes 14 decreases, and the number N of vanes 14 increases, resulting in the distance d between the vanes 14. As the capacitance C increases and the capacitance C and the number of vanes N increase, the quality factor Q decreases, so that the magnetron is driven at a low voltage while the magnetron is driven at a high voltage. The output and efficiency of the time can be obtained.

Therefore, by using the present invention, the magnetron is driven at a low voltage, thereby reducing the cost according to the structural shape, the power supply circuit, and the insulated circuit, and improving safety.

Claims (1)

In the magnet comprising a plurality of vanes arranged at equal intervals on the inner surface of the positive electrode body and the filament disposed in the inner central portion of the positive electrode body, the number of vanes is 12, the thickness t 'of the vanes A magnetron having a diameter of 1.15 to 1.3 mm and a ratio of the diameter (rc ') of the filament to the distance (ra') between vanes facing each other.