KR200348927Y1 - Grid coupling structure of low voltage driving ultra high frequency oscillation tube - Google Patents

Abstract

The present invention relates to a grid coupling structure of a low-voltage driving ultra-high frequency oscillator tube, wherein the disk-shaped insulating plate 20 is coupled between the first grid 134 and the second grid 142, so that A screw hole 41 is vertically formed in the lower center of the output coupler 40 coupled to the upper portion, and the ceramic bolt 45 is insulated from the screw hole 41 through an insulating ring 50. It is fastened through 50.

The present invention as described above, the first grid 134 and the second grid 142 by the insulating plate 20 interposed between the first grid 134 and the second grid 142 even when the ultra-high frequency oscillation tube is used continuously for a long time. Can maintain a constant gap to prevent short circuits.

Description

Grid Coupled Structure of Low Voltage Driving Microwave Oscillator Tube

The present invention relates to an ultra-high frequency oscillation tube of a microwave oven, and in particular, a circular insulating plate is inserted between a first grid and a second grid constituting the ultra-high frequency oscillation tube, so that the first grid and the second grid have a predetermined interval. It is configured to prevent the short circuit between the first grid and the second grid due to thermal deformation.

In general, microwaves are irradiated with food to cook foods by dielectric heating using frictional heat caused by the translational motion of water molecules contained in foods. A magnetron is provided that operates as.

The magnetron is a kind of two-pole vacuum tube that generates ultra-high frequency, and is composed of an input unit through which power is input as shown in FIG. 1, and an output unit through which microwaves are emitted to the outside, and an input unit including a condenser 11, a coil 12, and the like. When power is applied, hot electrons generated from the filament of the cathode 1 are emitted into the working space 4 between the tip of the plurality of vanes 3 coupled to the inner wall of the cylindrical anode 2 and the filament, and this working space In (4), a high voltage of 4 kV is applied between the cathode 1 and the vanes 3 constituting the anode 2 to form an electric field in the above-described working space 4.

At this time, the space 4 is provided with a magnetic circuit composed of a magnet 5 and a magnetic pole 6, thereby applying a magnetic field to the hot electrons, and thereby hot electrons perform a cycloid movement.

Subsequently, the energy generated according to this movement is transmitted to the vanes 3 and the straps 8, and through the output unit composed of the antenna 7 connected to the vanes 8 and the A ceramic 9, the A seal 10, and the like. Transfer to the cooking chamber to thaw or cook food.

When the magnetron emits hot electrons from the cathode (1), the electrons are accelerated under the influence of the electric field and the magnetic field, and move to the anode (2) during the rotational movement. Resonant frequency As described above, the resonance frequency is determined based on the values of 'L' and 'C' acting between the vanes 3 to generate microwaves, that is, ultrahigh frequencies when a predetermined resonance condition is satisfied.

By the way, the magnetron for the microwave oven having the above-described structure must be provided with a high voltage transformer and a high pressure diode as a peripheral device by operating by a high voltage of about 4 kW, and adopting a resonance method by electromagnetic movement in a magnetic field. Therefore, the need for a magnet has a high weight and at the same time consumes a lot of cost.

On the other hand, to solve the problem of the magnetron driven by a high voltage as described above, Korean Patent Application No. 97-36327 is filed by the present applicant is known, such patent application No. 97-36327 is AC 120V, Alternatively, DC power is applied from a power generator that boosts a commercial power of 220V to a DC power of 500 to 700V to generate ultra-high frequency.

The present invention, as shown in Figure 2, when the cathode 132 located on the upper portion of the heater 120 is heated according to the heat generated by the heater 120 emits hot electrons, and thus is emitted according to the heat generated by the heater 120 The hot electrons are focused by a bias voltage of 50 to 100 V DC applied between the cathode 132 and the first grid 134 and pass through the second grid 142.

In this process, the hot electrons are accelerated by a potential difference between an operating voltage of DC 500 to 700 V applied between the anode 146 and the cathode 132 to induce a surface current between the anode 146 to form a microwave. On the other hand, the microwave formed according to this process is radiated through the antenna 150 in the center of the anode 146, and together with a portion of the microwave formed in the output cavity 140 in the center between the input and output cavity (130, 140) A feedback rod 160 that feeds back into the cavity 130 is installed to amplify and resonate microwave power.

In particular, unlike the conventional magnetron operating at a high voltage of 4 kW, such a low-voltage driving ultra-high frequency oscillator tube has a low voltage of 500 to 700 V, so the voltage can be stepped up without a separate boosting transformer to simplify the structure of the product. Visible effects such as increased safety, lighter weight of the product, and mass production at lower prices were expected.

Meanwhile, in the low voltage driving ultra-high frequency oscillator tube, the first grid 134 and the second grid 142 made of ultra thin plates are respectively fixed, and a short circuit between the first grid 134 and the second grid 142 is performed. 3, the lower portions of the first grid 134 and the second grid 142 are supported by the first grid holder 135 and the second grid holder 143 to prevent the first grid 134 and The mechanical strength of the second grid 142 is reinforced.

In addition, in the process of fixing the first grid holder 135 and the second grid holder 143 together with the through hole in the inner side of the first grid holder 135 and the second grid holder 143, respectively, radially After forming, the first bolt holder 139 and the second grid holder 143 are interposed between the spacer 141 having a disc shape, and the bolt 139 is fastened through the through hole. The grid 134 and the second grid 142 are combined to maintain a constant gap.

However, in the conventional low voltage driving ultra-high frequency oscillation tube as described above, the first grid holder 135 and the first grid holder 134 and the second grid 142 are supported by the spacer 141, respectively. Shorting between the first grid 134 and the second grid 142 is prevented as the two grid holders 143 are spaced by a predetermined gap, respectively, while the first grid 134 and the second grid 142 of the second grid 142 are prevented. The gap is maintained by its rigidity.

Therefore, in the conventional low voltage driving ultra-high frequency oscillation tube, the first grid 134 and the second grid 142 are lowered by their own weight, and accordingly, the interval between the first grid 134 and the second grid 142 is reduced. It was difficult to accurately maintain the temperature, especially when the first grid 134 and the second grid 142 due to a long time continuous operation occurs, the first grid 134 and the first to operate the high pressure of several hundred volts or more Problems such as a short circuit occurring between the two grids 142 occur.

The present invention has been made to solve the problems occurring in the conventional low-voltage ultra-high frequency oscillation tube as described above, the technical problem of the present invention is to provide a circular insulating plate between the first and second grid constituting the ultra-high frequency oscillation tube It is to provide a means for preventing the short circuit between the first grid and the second grid due to the thermal deformation by inserting the first grid and the second grid to maintain a constant interval.

The technical problem of the present invention as described above,

A first grid and a second grid are coupled in parallel to an upper portion of a cathode that emits hot electrons as the heater generates heat, and an input coupler is vertically installed at a lower portion of the first grid, and an output is disposed at an upper portion of the second grid. In the low voltage driving ultra-high frequency oscillator tube having the coupler installed vertically,

A through hole is formed in the center between the first grid and the second grid, and a disk-shaped insulating plate having the same thickness as the gap between the first grid and the second grid is joined.

A screw hole is vertically formed at the lower center of the output coupler coupled to the upper portion of the first grid.

Inside the screw hole provides a grid coupling structure of the low-voltage driving ultra-high frequency oscillating tube, characterized in that the ceramic bolt is inserted through the lower portion of the first grid and protruded to the upper portion of the second grid via an insulating ring. Is achieved.

Hereinafter, an embodiment of a grid coupling structure of a low voltage driving ultra high frequency oscillation tube according to the present invention will be described in detail with the accompanying drawings.

1 is a schematic cross-sectional structural view showing an example of a magnetron for a microwave oven having a conventional structure;

2 is a cross-sectional structure diagram of a conventional low voltage driving ultra-high frequency oscillation tube,

3 is a detailed view of the main part of a conventional low voltage driving ultra-high frequency oscillation tube,

4 is an exploded perspective view illustrating main parts of an embodiment of the present invention;

5 is a detailed view of the main part of a low-voltage driving ultra-high frequency oscillation tube to which the present invention is applied.

<Explanation of symbols for the main parts of the drawings>

20: insulation plate 21: through hole

40: output coupler 41: screw hole

45 ceramic bolt 50 insulation ring

60: input coupler 120: heater

132: cathode 134: first grid

142: second grid

4 is an exploded perspective view showing main parts of an embodiment of the present invention, and FIG. 5 is a detailed view of a main portion of a low voltage driving ultra-high frequency oscillation tube to which the present invention is applied. In order to accelerate the hot electrons emitted from the cathode 132, the first grid 134 and the second grid 142 coupled to the upper portion of the cathode 132 are separated by the insulating plate 20, and the insulating plate ( The first grid 134 by fixing the first grid 134 and the second grid 142 including the 20 to the lower end of the output coupler 40 by the ceramic bolt 45 in the state of the insulating ring 50 through. ) And the second grid 142 to prevent a short circuit due to thermal deformation.

Here, the insulating plate is in close contact with the upper portion of the first grid 134 and the lower portion of the second grid 142 so as to space the central portions of the first grid 134 and the second grid 142 at even intervals. 20 is formed in a disk shape so that the support for the first grid 134 and the second grid 142 is uniformly made over each part, and the through hole 21 is formed in the center.

In this case, the insulating plate 20 may have the same thickness as the gap between the first grid 134 and the second grid 142 such that the first grid 134 and the second grid 142 may maintain a constant gap. Make sure

Subsequently, the output coupler 40 vertically installed on the upper portion of the second grid 142 forms a screw hole 41 vertically at the lower end thereof, and the first grid 134 is formed inside the screw hole 41. And a ceramic bolt 45 inserted through a lower portion of the first grid 134 and protruding to an upper portion of the second grid 142 while the insulating plate 20 is interposed between the second grid 142. By fastening, the first grid 134 and the second grid 142 are fixed to the lower end of the output coupler 40 in a state spaced apart at regular intervals.

At this time, the insulating ring 50 is provided between the lower portion of the output coupler 40 and the second grid 142 to prevent a short circuit due to direct contact between the second grid 142 and the output coupler 40 in the above process. Intervene.

Reference numeral 42 in the figure increases the holding area with the insulating ring 50 by increasing the contact area with the insulating ring 50, while preventing the left and right flow of the insulating ring 50 from the output coupler 40. A recess 61 is a space formed in the upper portion of the input coupler 60 so as to prevent contact between the ceramic bolt 45 fastened to the screw hole 41 of the output coupler 40 and the input coupler 60. It is wealth.

The operation of the present invention made of a structure as described above will be described below.

The grid coupling structure of the low-voltage driving ultra-high frequency oscillation tube according to the present invention, the first grid 134 to accelerate the hot electrons emitted from the cathode 132 by the potential difference in accordance with the heat generated by the heater 120 during the generation of the ultra-high frequency And the first grid 134 and the second grid 142 by holding the center of the second grid 142 is fixed to maintain a constant gap.

Looking at the coupling process of the present invention, the first grid 134 and the second grid 142 described above through the insulating plate 20 between the first grid 134 and the second grid 142. Should be spaced at regular intervals.

After the completion of the process, the ceramic bolt 45 is inserted through the lower portion of the first grid 134 to penetrate the insulating plate 20 in which the ceramic bolt 45 is placed on the first grid 134. Protrude through the upper portion of the second grid 142 via the ball 21, and then output with the insulating ring 50 positioned between the output coupler 40 and the second grid 142 The ceramic bolt 45 is fastened with the screw hole 41 of the coupler 40.

Subsequently, when the fixing of the center of the second grid 142 including the first grid 134 is completed, the first grid holder 135 and the second grid supporting the first grid 134 and the second grid 142 are completed. The fixing of the first grid holder 135 and the second grid holder 143 is completed by fastening the bolt 139 with the spacer 141 interposed between the grid holders 143. After completion of this process, Couples the cathode housing 121, the input coupler 60, etc., to which the heater 120 and the cathode 132 are coupled.

The present invention coupled according to the above process has a state in which the first grid 134 and the second grid 142 is fixed by the first grid holder 135 and the second grid holder 143, respectively, The ceramic bolts 45 inserted through the centers of the first grid 134 and the second grid 142 are fastened through the threaded holes 41 of the output coupler 40 so that the first grid 134 and the second grid ( 142 is fixed by a strong fixing force.

In particular, the insulating plate 20 is interposed between the first grid 134 and the second grid 142 to heat the first grid 134 and the second grid 142 according to the continuous operation of the microwave oscillation tube. Even when deformation occurs, the first grid 134 and the second grid 142 are maintained by the insulating plate 20 to prevent a short circuit between the first grid 134 and the second grid 142.

As described above, according to the present invention, a circular insulating plate 20 is interposed between the first grid 134 and the second grid, and through the centers of the first grid 134 and the second grid 142. The first grid 134 and the second grid 142 are coupled by the strong fixing force by fastening the ceramic bolts 45, while the gap between the first grid 134 and the second grid 142 is constant. maintain.

Accordingly, the present invention is a direct contact between the first grid 134 and the second grid 142 even when the thermal deformation occurs in the first grid 134 and the second grid 142 according to the continuous use of the ultra-high frequency oscillation tube. Short circuits can be prevented.

Although the present invention has been illustrated and described with respect to specific preferred embodiments, the present invention is not limited to the above-described embodiments, and is not limited to the above-described embodiments of the present invention without departing from the gist of the present invention as claimed in the utility model registration claims. Any person with ordinary knowledge will be able to make various modifications.

Claims (1)

The first grid 134 and the second grid 142 are coupled in parallel to an upper portion of the cathode 132 that emits hot electrons as the heater 120 generates heat, and a lower portion of the first grid 134 is disposed below. In the low-voltage driving ultra-high frequency oscillating tube in which the input coupler 60 is vertically installed and the output coupler 60 is vertically installed above the second grid 142, A through hole 21 is formed in the center between the first grid 134 and the second grid 142, and has a disc shape having the same thickness as the gap between the first grid 134 and the second grid 142. The insulating plate 20 on the top, A screw hole 41 is vertically formed at the lower center of the output coupler 40 coupled to the upper portion of the first grid 134. Inside the screw hole 41 is inserted through the lower portion of the first grid 134 to fasten the ceramic bolt 45 protruding to the upper portion of the second grid 142 via the insulating ring 50. The grid coupling structure of the low-voltage driving ultra-high frequency oscillator tube.