KR970005952Y1 - A seal and f seal of magnetron for microwave oven - Google Patents

Abstract

none

Description

Ash and F seal structure of magnetron for microwave oven

1 is a half longitudinal cross-sectional view showing a conventional magnetron for a microwave oven

FIG. 2 is a longitudinal sectional view showing a state in which permanent magnets are installed on the ace and fsea of FIG.

Figure 3 is a longitudinal cross-sectional view showing the present invention

* Description of the symbols for the main parts of the drawings *

1: Ace2 2: Fsea

3: permanent magnet 4: working space

5: 2-step difference l1, l2: length

h1, h2: height

The present invention relates to the structure of the ace and f seal of the magnetron for a microwave oven, and more specifically, to permanently place magnets in the ace and f seal of the magnetron for a microwave oven to maintain a uniform magnetic flux density in the working space. It is to improve the efficiency.

In general, a microwave magnetron for generating harmonics is provided with a filament 6, which is a series cathode of a cathode that emits hot electrons in the center in the axial direction, as shown in FIGS. 1 and 2. It is a kind of bipolar vacuum tube provided with the anode 7 of the radial cathode structure around (6), the upper and lower parts to apply magnetic flux to the working space (4) between the filament (6) and the anode (7) The yoke (8) (9) is provided, and the permanent magnet (3) and the magnetic circuit to form a magnetic field on the upper and lower yoke (8) (9), the upper and lower aces and the f seal (1a) (2a) Phosphor stimulus 10 is provided in turn.

In addition, in order to send the high frequency energy transmitted to the anode 7 to the outside (cavity), an antenna lead 11, an ace 1a, an antenna ceramic 12, an antenna cap 13, etc. are installed. A heat radiation fin 15 is installed to dissipate heat generated by the collision of hot electrons to the outside in the anode vane 14 which receives the electron energy generated from the filament 6 in the lower yoke 8 and 9, and functions. In order to prevent the unwanted harmonics generated in the space 14 from flowing back to the power source, the choke coil 17 and the high voltage capacitor 18 are provided in the filter box 16.

Therefore, the magnetron has a working space (4) in which the magnetic field of the permanent magnet (3) is formed between the anode vanes (14) and the filaments (6) by forming a magnetic circuit along the upper and lower yokes (8) (9) and the magnetic poles (10). A magnetic field is formed in the field, and an electric field is formed between the anode vane 14 and the filament 6, and the hot electrons emitted from the filament 6, which is a cathode, by the electric field and the magnetic field are harmonics of electron energy in the working space 4. The harmonic energy transmitted from the working space (4) to the anode vane (14) is transferred to the ace (1a), the antenna ceramic (12), the antenna cap (13), and the antenna lead (11). Energy is transmitted to the outside through the output.

In this case, when energy is transmitted to the outside through the output part, the energy transmitted is transmitted not only the fundamental wave but also the harmonics. Therefore, in the case of the microwave oven magnetron, the fundamental wave is 2.45GMZ, which is the frequency band used in satellite broadcasting. Therefore, in general, the choke 19 having a quarter length of a specific harmonic wavelength is used to remove and suppress the harmonics between the ace 1a of the battery output unit and the antenna lead 11.

In addition, the magnetic flux density in the working space 4 varies depending on the thickness and characteristics of the permanent magnets 3 installed on the circumferential surfaces of the ace and f seals 1a and 2a, so that the output and efficiency of the magnetron are different. The design of the magnetic circuit considering the position and temperature characteristics of the permanent magnet 3 is important.

However, such a conventional magnetron has a permanent magnet (3) is fitted to the circumferential surface of the ace and f seal (1a) (2a), the permanent magnet (3) and the acy and f seal (1a) (2a) Since there is a gap therebetween, the permanent magnet 3 flows or is eccentrically positioned at the center of the working space 4, thereby failing to form a uniform magnetic flux density in the working space 4, thereby lowering the output of the magnetron and less than 1 kW. In addition to generating noise of the permanent magnet 3, the permanent magnet 3 is biased to one side, and if one part is in contact with the acyle and the f seal 1a, 2a, the permanent magnet 3 becomes a temperature rising factor. 3) There was a problem that the output of the magnetron was greatly reduced because it did not exhibit this characteristic.

The present invention is to solve the above problems, the present invention is to place the permanent magnet in the acyle and F seal of the magnetron to prevent the eccentricity to maintain the magnetic flux density uniformly in the working space to improve the magnetic efficiency It is an object of the present invention to provide the structure of the ash seal and the F seal of the magnetron for a microwave oven which can not only increase the output of the magnetron but also greatly reduce the noise of 1 dB or less caused by the magnetic field unevenness.

In order to achieve the above object, the present invention is a bending part connected to the wing surface and the communication surface of the ash seal and the F seal is coincident with the center axis of the permanent magnet and the working space, the permanent magnet is positioned without flow and at the same time It is an ace seal and f seal structure of a magnetron for a microwave oven, in which a stepped two-stage step is formed to maintain a constant gap between the f seal and the permanent magnet.

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIG. 3.

3 is a longitudinal cross-sectional view showing the present invention, the permanent magnet (3) and the working space (4) in the bent portion is connected to the wing surface and the cylindrical surface of the ace and f seal (1) (2) of the microwave oven magnetron The two-stage formula is calculated so that the permanent magnet (3) is in the correct position without flow and the axial between the ace and f seal (1) (2) and the permanent magnet (3) is kept constant. The height 5 of the first stage upper surface on which the car 5 is formed and the permanent magnets 3 of the stepped second stage 5 are placed, and the second stage inner side of the permanent magnets 3 are supported. ) Is formed larger than the length l2 of the two-stage upper surface and the height h2 of the one-stage inner side portion.

According to the present invention configured as described in FIG. 3, two-stepped steps 5 are formed in stepped portions of the ace and f-seals 1 and 2 of the microwave oven magnetron, respectively. The length (l1) of the first-stage upper surface on which the permanent magnet (3) is mounted and the height (h1) supporting the two-stage inner side of the permanent magnet (3) are the length (ℓ2) of the two-stage upper surface and the height of the first-stage inner side. It is formed larger than (h2) so that when the permanent magnet (3) is inserted into the circumferential surface of the acyle and f seal (1) (2) so that the permanent magnet (3) is placed on the first stage upper surface of the second step (5) At the same time, the permanent magnet (3) is positioned in the right position without flow because it is fitted to the second side side, so that the gap between the ace and f seal (1) (2) and the permanent magnet (3) is kept constant and permanent. By preventing the eccentric contact of the magnet (3) it is possible to prevent the temperature of the permanent magnet (3) to rise.

In addition, by maintaining the magnetic flux density uniformly in the working space 4, the output of the magnetron according to the improvement of the magnetic efficiency can be improved, and the noise of 1 dB or less caused by the magnetic field nonuniformity can be greatly attenuated.

In addition, since the permanent magnet (3) is placed on the first stage of the second step (5) because the space between the wing surface and the permanent magnet (3) of the acyle and f seal (1) (2) is formed While suppressing heat transfer from the aceyl (1) to the permanent magnet (3) and at the same time more smoothly the air flow between the aceyl (2) and the permanent magnet (3) of the magnetron by the temperature rise of the permanent magnet (3) It is possible to greatly reduce the power drop.

As described above, the present invention is formed by the second step 5 formed at the bent portions of the ace and f seal 1 and 2 of the microwave oven magnetron, thereby permanently forming the ace and f seal 1 and 2. By placing the magnet 3 in the correct position to prevent eccentricity, the magnetic flux density in the working space 4 is maintained uniformly, the output of the magnetron can be increased due to the improvement of the magnetic efficiency, and the noise caused by the magnetic field nonuniformity can be greatly attenuated. , It is a very useful design that can suppress the rise of the temperature of the permanent magnet (3) by smoothing the air flow.

Claims (2)

Permanent magnet and the center axis of the working space coincide with the bent part where the wing surface and the cylindrical surface of the A / S seal are connected, so that the permanent magnet is positioned without flow and the gap between the A / S and F seal is permanent. The asheil and fsea structure of the magnetron for a microwave oven, characterized in that the two-step difference of the formula is formed so as to be maintained. The magnetron for microwave oven according to claim 1, wherein the two-stage step has a length of the first-stage upper surface on which the permanent magnet is placed and the height of the two-stage inner side of the permanent magnet is greater than the length of the two-stage upper surface and the height of the first-stage inner side. Ash and Fsea structures.