KR100240345B1 - Microwave generator for use in a microwave oven - Google Patents

Abstract

The present invention relates to an ultra-high frequency oscillation tube for a microwave oven, and compared to a microwave oven employing a conventional klystron, not only ensures stability against high pressure, but also requires a high voltage circuit unit compared to a conventional microwave oven using a conventional magnetron. Therefore, the weight reduction is achieved, and the electron beam is focused using the first and second grids, so that an external magnetic field magnet is unnecessary, and the cathode, the first and second grids, and the anode form a planar structure, thereby simplifying the structure. The weight reduction is achieved, and since a separate bias power supply from the outside is unnecessary by the auto bias function of the first grid, the cost of the product is reduced.

Description

Microwave Oscillation Tube for Microwave Oven

The present invention relates to an ultra-high frequency oscillation tube for a microwave oven, and more particularly, to a microwave high-frequency oscillation tube that can achieve a light weight while eliminating the risk due to a simple voltage.

As is well known, a microwave oven employs, for example, a magnetron driven at a high voltage of 4 kV as an ultra high frequency oscillation tube. This magnetron is a kind of two-pole vacuum tube that generates microwaves, and as shown in FIG. 1, when electric power is applied to an input part composed of a condenser 11, a choke coil 12, and the like, the hot electrons emitted from the filament 1 of the cathode part. Is emitted into the working space 4 between the ends of the plurality of vanes 3 and the filament 1 extending on the inner wall of the cylindrical anode 2, and an electric field of about 4 kV is formed in the working space 4. . In addition, a magnetic field is applied to the working space 4 by a magnetic circuit composed of a magnet 5 and a magnetic pole 6 so that hot electrons undergo a cycloid movement, and the energy of the movement is taken into the vane 3 and the strap 8. ) Is radiated to the cooking chamber through an antenna 7 connected to the vane 3, and an output portion composed of the A ceramic 9, the A seal 10, and the like.

However, such a conventional magnetron for a microwave oven requires a high voltage transformer and a high pressure diode according to a high pressure driving, so there is a problem in safety, and a magnet is required because it adopts a resonance method by electromagnetic movement in an electromagnetic field. This was heavy and expensive to manufacture.

1 and 2 illustrate a microwave oven employing Klystron disclosed in US Pat. No. 5,541,391 as an ultra-high frequency oscillating tube. As shown in FIG. 2, the chrystron 40 includes an input terminal 42 for accommodating power, a klystron main body 41 for generating microwaves in response to the supply of power to the input terminal 42, and , An antenna 32 for transmitting microwaves from the Klystron body 41, a cooling unit 43 for dissipating heat generated in the Klystron body 41 to the outside, and an electron beam concentrator provided to receive electrons. And a cooling unit 43 supporting the cooling fins 44 and the cooling fins 44 arranged to disperse heat generated by the reception of electrons, and having an electron beam concentrator 49. It consists of a cooling rod 46 arranged to transfer heat from the cooling fins 44 and a closure 48 surrounding the cooling fins 44.

The klystron 40 also receives a power supply via the input terminal 42, and a pair of electron guns 50, which generate electrons by the received power supply, and a pair of electron guns 50 and the electron beam concentrator 49, respectively. The magnet 52, the yoke 54 which acts as a guide | route which comprises the closed loop by this magnet 52, and the tube 56 interposed between the mark 52 with the some cavity is included.

However, the microwave oven employing Klystron still applies high voltage, so the input terminal has to be insulated from the Klystron body with a separate insulation member, so the product becomes heavy and the movement method of the electron is complicated, so the cooling structure is complicated and many It should be a structure having a cavity of, and a magnet is required because the focusing structure of the electron beam is required, and the structure has a complex disadvantage.

Accordingly, the present invention has been made in accordance with the present invention, the structure is simple, to provide a microwave high frequency oscillation tube that can eliminate the risk due to high voltage and achieve a light weight.

As a means for achieving the above object, the microwave microwave oscillation tube of the present invention is a power input unit, a heat generating means for generating heat by receiving power from the power input unit, and is sequentially installed at a predetermined interval on top of the heat generating means An input cavity of a space surrounded by a cathode, a first grid, and a choke structure provided between the cathode and the first grid, wherein the cathode is heated to a predetermined operating temperature by the heat of the heat generating means to emit hot electrons, The first grid is applied with a bias voltage to control and focus electrons emitted from the cathode, and the choke structure conducts surface current to form a microwave inside the input cavity, and between the cathode and the first grid. Input cavity shielding direct current and a plurality of cooling fins arranged in a stack to radiate heat The high-decelerated electron beam is a space surrounded by an extinguishing anode and a second grid installed on top of the first grid so that surface current is induced while electrons passing through the first grid of the input cavity pass. An output cavity in which an electron focused on an input cavity is densely modulated and accelerated by a potential difference between the first grid and a second grid, and a microwave is formed by surface current induced in the second grid; And radiation means for radiating microwaves, and feedback means provided between the input and output cavities to feed back a portion of the microwaves formed in the output cavity to the input cavity.

1 is a schematic cross-sectional view showing the structure of the macronet used as a conventional microwave microwave tube.

2 is a schematic cross-sectional view showing the structure of Klystron used as a conventional microwave microwave tube.

3 is a cross-sectional view showing the structure of a microwave oven for microwave oven according to an embodiment of the present invention,

4 is an enlarged detail view of the main portion of FIG. 3;

5 is a perspective view illustrating the cathode of FIG. 4;

6 is a perspective view illustrating the first and second grids of FIG. 4.

Explanation of symbols on the main parts of the drawings

100: the invention ultra-high frequency oscillation tube 102: bracket

104: filter box cover 110: power input unit

120: heater 130: input cavity

132: cathode 134: first grid

136: choke structure 140: output cavity

142: second grid 144: projection

146: anode 148: cooling fin

150 antenna 152 coupling end

154: antenna ceramic 156: antenna cap

160: feedback rod 170: slot-shaped rectangular opening

172: ceramic pin

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

Microwave oscillation tube for microwave oven according to an embodiment of the present invention, as shown in Figure 3, the power input unit 110, the heater 120 and the filter box 105 is covered with a cover 104 in the lower portion; , The input cavity 130, the output cavity 140, and the feedback rod 160 are provided, and the antenna 150 in the anode 146 is provided in the bracket 102. The interior of the filter box 105 and the antenna 150 portion of the anode 146 maintain a vacuum. This bracket 102 is preferably the same as that used for a conventional microwave magnetron.

In the ultra-high frequency oscillation tube 100 of the present invention, the cathode 132, which is an electron radiator, emits hot electrons by an indirect heating method by the heat generation of the heater 120 composed of an annular filament as a heat generating means. That is, as shown in FIG. 5, when the cathode 132 placed on the top surface of the heater 120 is heated to about 600-1200 ° C. by the heat of the heater 120, the electrons are emitted.

The input cavity 130 is a space surrounded by the cathode 132, the first grid 134, and the choke structure 136, and the cathode 132 has a hole in the center as shown in FIGS. 4 and 5. A ring-shaped disk formed, the first grid 134 arranged at a predetermined interval on top of the cathode 132 is applied to the input cavity 130 to control the electrons emitted from the cathode 132 to the input cavity 130 by applying a bias voltage Belongs. At this time, the first grid 134 and the cathode 132 is electrically insulated, that is, the direct current must be shielded, the surface current forming the microwave inside the input cavity 130 must be energized, so choke for this purpose The structure 136 is arranged between the cathode 132 and the first grid 134.

The output cavity 140 arranged on the upper portion of the input cavity 130 is installed to face the upper portion of the first grid 134 of the input cavity 130 so that surface current is increased while electrons passing through the first grid 134 pass. A space surrounded by the induced second grid 142 and the anode 146 having protrusions 144 protruding downward from the bottom surface, in which the electrons focused on the input cavity 130 are densely modulated and thus, the first grid. Accelerated by the potential difference between 134 and the second grid 142, the microwave is formed by the surface current induced in the second grid 142. The anode 146 that dissipates the slowed-down electron beam is also stacked with a plurality of cooling fins 148 to radiate heat.

As shown in FIG. 6, the first and second grids 134 and 142 are identical to each other in a shape corresponding to the cathode 132 as a metal material, and have a slot-shaped quadrangular shape along a circumferential direction around an inner hole. An opening 170 is formed and a predetermined gap is maintained by the ceramic pin 172 provided between the choke structure 136 and the output cavity 140.

The electrons focused on the input cavity 130 are densely modulated by the automatic shielding function of the bias power of the first grid 134 to pass through the first grid 134, and at this time, the input / output cavities 130 and 140 insulated from each other. When the operating voltage is applied, the potential difference is generated therebetween, and electrons passing through the first grid 134 are accelerated to pass through the second grid 142, so that surface current is generated in the output cavity 140. Induced. As a result, microwaves are formed in the output cavity 140, and the formed microwaves penetrate through the center of the anode 146 and are radiated through the antenna 150 formed in the output cavity 140. For this purpose, the coupling end 152 of the antenna 150 is located in the output cavity 140. The antenna ceramic 154 and the antenna cap 156 connected to the upper portion of the antenna 150 have the same structure as a conventional magnetron.

On the other hand, the ultra-high frequency oscillation tube 100 of the present invention, the feedback rod 160 for feeding back a portion of the microwave formed in the output cavity 140 in the center between the input and output cavity (130, 140) to the input cavity 140 This is installed to amplify and resonate microwave power.

According to the present invention, compared to the conventional microwave oven, not only the stability to high pressure is secured, but also the weight of the first and second grids is achieved because there is no need for a high-voltage circuit unit compared to a conventional microwave oven using a conventional magnetron. By converging the electron beam, the magnet for external magnetic field becomes unnecessary, and the cathode, the first and the second grid and the anode form a planar structure, so that the structure is simplified and the weight is achieved, and the auto-bias function of the first grid is achieved. This eliminates the need for a separate bias power supply from the outside, resulting in a cost-effective product.

Claims (6)

In the microwave oven for microwave oven, Power input unit, Heating means for generating heat by receiving power from the power input unit; An input cavity of a space enclosed by a cathode sequentially arranged at a predetermined interval on the heat generating means, a first grid, and a choke structure provided between the cathode and the first grid, the cathode being predetermined by heat generation of the heat generating means. Heated to an operating temperature of to emit hot electrons, and the first grid is supplied with a bias voltage to control and focus electrons emitted from the cathode, and the choke structure is electrically energized to form a microwave inside the input cavity. An input cavity shielding a direct current between the cathode and the first grid; A plurality of cooling fins are arranged in a stack to radiate heat, and an anode for dissipating the reduced electron beam and an electron passing through the first grid of the input cavity are installed on top of the first grid to induce surface currents. A space enclosed by a second grid, in which the electrons focused in the input cavity are densely modulated and accelerated by the potential difference between the first and second grids, and by the surface current induced in the second grid, Output cavity in which is formed, Radiating means for radiating microwaves formed in the output cavity; And a feedback means provided between the input and output cavities to feed back a portion of the microwaves formed in the output cavity to the input cavity. The microwave oscillation tube according to claim 1, wherein the density modulation of the electrons accumulated in the input cavity is performed by an automatic shielding function of the bias power supply of the first grid. The microwave oven of claim 1, wherein the inside of the microwave generator maintains a vacuum. The method of claim 1, wherein the cathode is a disk in the form of a ring, the first and second grid is a circular metal material corresponding to the cathode, the slot-shaped rectangular opening in the circumferential direction around the inner hole is formed Microwave oscillation tube for microwave, characterized in that. The electronic device of claim 1, wherein the feedback means feeds back a portion of the microwaves formed in the output cavity to the input cavity using a feedback rod formed at the center of the cavities to amplify and resonate the power of the microwave. Microwave oscillation tube for microwave oven. The microwave oscillation tube of claim 1, wherein the input / output cavities are insulated from each other, and the distance therebetween maintains a distance of several tens to several hundred microns.

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