KR100262278B1 - Blocking capacitor for use in a micro-generator of a microwave oven - Google Patents

Abstract

PURPOSE: A blocking capacitor of a ultra high frequency oscillator tube for microwave range is provided to reduce manufacturing costs by improving a structure of a blocking capacitor. CONSTITUTION: An upper surface of an upper portion of a capacitor is polished and a metalizing face is formed thereon. A metal cap(300) is loaded on the remaining part of the capacitor. The metal cap(300) comprises an inner cylindrical portion(320) and an outer cylindrical portion(340) and a bottom plate(360) for connecting the inner cylindrical portion(320) with an outer cylindrical portion(340). A height of the inner cylindrical portion(320) is higher than a height of the outer cylindrical portion(340). An end portion(342) of the outer cylindrical portion(340) is bent and overlapped with the metal rising face(210). A discontinuous portion is formed between a heater housing(190) and an upper end portion of the inner cylindrical portion(322).

Description

Blocking Capacitor of Microwave Oscillator for Microwave Oven

The present invention relates to a blocking capacitor of a microwave microwave oscillation tube, and more particularly, to a blocking capacitor of a microwave microwave oscillation tube that can be easily manufactured by adopting a metal cap shape.

In this regard, the present applicant has proposed Korean Patent Application No. 97-36327 for a microwave microwave oscillation tube having a simple structure and eliminating the risk of high voltage and achieving a light weight. As shown in FIG. 1, the ultra-high frequency oscillation tube is mounted on the upper surface of the heater 120 by placing the cathode 132 as a ring-shaped disk-shaped electron radiator in an indirect heating method and generating heat by the heater 120. When the cathode 132 is heated to about 600-1200 ° C. by the indirect heating method, hot electrons are emitted, and the released hot electrons are biased to the first grid 134 arranged at predetermined intervals on the cathode 132. As it is applied, it controls and focuses on the input cavity 130.

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.

Meanwhile, a feed rod 160 for feeding back part of the microwaves formed in the output cavity 140 to the input cavity 140 is installed at the center between the input / output cavities 130 and 140 to amplify and resonate the power of the microwave. .

As shown in FIG. 2, the input cavity 130 includes a grid holder 180 supporting the first grid 134 and a space surrounded by the heater housing 190, and a blocking capacitor 136 made of alumina ceramic. ) Is arranged between the grid holder 180 and the heater housing 190, so that when the cathode 132 receives the heat of the heater 120 to emit hot electrons, is arranged at a predetermined interval on top of the cathode 132 Focusing of the hot electrons occurs due to the bias voltage applied to the one grid 134. At this time, the input cavity 130 is designed to resonate near the oscillation frequency of 2450 MHz, so that the voltage applied to both ends of the resonance must be insulated. , Ultra-high frequency current (i) is to be energized to flow along the inner surface of the grid holder 180 and the heater housing, for this purpose blocking capacitor 136 to form a metal plate or metalizing surface on the discontinuous surface As shown in FIG. 3, the position of the discontinuous surface should be a portion λ / 4 from the reference surface when the inner surface of the flange portion 182 of the grid holder 180 is referred to as a reference surface. In the related art, one end is connected to the flange portion 182 of the grid holder 180, and the length from the reference plane to the portion bent downward is measured. l ₁ This is referred to, the length to the inwardly bent portion toward the heater housing 190 l ₂ In this case, the position P of the discontinuous surface is determined as follows.

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However, the conventional blocking capacitor of the microwave oven tube is expensive because of the characteristics of the ceramic, there is a problem that precise processing is difficult. For example, the thickness of the blocking is closely related to the assembling precision of the grid and cathode assembly to be assembled later, and in order to meet this dimension, diamond polishing on the inner surface, the outer surface, and the upper and lower portions is difficult, so that the manufacturing process is difficult. In addition, since the internal shape changes depending on the roughness of the ceramic working surface, there is a possibility that the flow of electromagnetic waves may be poor.

In addition, since the surface of the metal material or metallizing is used in the form of silk printing, it is difficult to simultaneously perform the inner surface and the outer surface, and there is a problem that metallizing is difficult because it is not a constant plane.

Accordingly, the present invention has been devised in accordance with the present invention, and an object thereof is to provide a blocking capacitor of a microwave oven tube that can be easily manufactured by employing a metal cap structure.

As a means for achieving the above object, the blocking capacitor of the microwave microwave oscillation tube of the present invention comprises a grid holder in which the input cavity supports the first grid, a heater housing, and a blocking arranged between the grid holder and the heater housing. Comprising a space enclosed by a capacitor, and forming a metal plate or metalizing surface on the surface of the blocking capacitor and has a discontinuous surface, when the inner surface of the flange portion of the grid holder is referred to as a reference surface, the discontinuous surface is a portion of λ / 4 In the blocking capacitor of the microwave oscillation tube for microwave positioning, wherein the metalizing surface is formed on the upper surface of the blocking capacitor, the remaining portion is composed of the inner and outer plates and the bottom plate connecting the inner and outer plates, the outer plate than the inner plate Mounting and assembling a metal cap having a higher height of the plate, the end of the outer plate Are assembled so as to overlap with the metallizing surface, to the discontinuous surface of the upper end from within tongpan is characterized in that the heater housing extension.

Blocking capacitor of the present invention, since only the upper surface of the ceramic material, and the remaining portion is equipped with a metal cap, there is an effect that the processing is easy and the manufacturing cost is low.

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

FIG. 2 is an enlarged detailed view of a mounting state of the blocking capacitor of FIG. 1;

3 is a schematic view showing a metal cap mounted on a blocking capacitor according to a preferred embodiment of the present invention, and a mounting state thereof.

<Description of the code | symbol about the principal part of drawing>

120: heater 130: input cavity

132: cathode 134: first grid

140: output cavity 142: second grid

146: anode 150: antenna

160: feedback rod 180: grid holder

190: heater housing 200: blocking capacitor

210: metalizing surface 300: metal cap

320: inner plate 340: outer plate

322: upper end 342: end

Hereinafter, with reference to the accompanying drawings will be described in detail the blocking capacitor of the microwave microwave tube according to a preferred embodiment of the present invention. For convenience of explanation, the same reference numerals are given to the same configuration as in the prior art.

3 shows an embodiment of the blocking capacitor of the present invention, the blocking capacitor 200 of the present invention, as shown, after grinding the upper surface, to form a metalizing surface 210.

In the remainder of the blocking capacitor 200 of the present invention, the metal cap 300 is mounted without performing post-processing after processing within a tolerance range. Metal cap 300 is composed of a bottom plate 360 connecting the inner and outer plate 320, 340 and the inner and outer plate 320, 340, the height of the outer plate 340 than the inner plate 320 Higher is preferred.

The metal cap 300 is bent to overlap the end 342 of the outer cylinder plate 340 with the metalizing surface 210 of the upper surface, between the heater housing 190 and the upper end 322 of the inner cylinder 320 A portion of the heater housing 190 extends to form a discontinuous surface of about 2 mm in length.

As described above, the blocking capacitor of the microwave microwave oscillation tube of the present invention is metallized after polishing only the upper surface of the ceramic, and the rest is equipped with a metal cap, so that the processing is easy and the manufacturing cost is reduced. Have

Claims (1)

The input cavity comprises a grid holder supporting the first grid, a heater housing, and a space surrounded by a blocking capacitor arranged between the grid holder and the heater housing, and forming a metal plate or a metallized surface on the surface of the blocking capacitor. In the blocking capacitor of a microwave high frequency oscillating tube for a microwave oven having a discontinuous surface, wherein the discontinuous surface is located at a portion of λ / 4 when the inner surface of the flange portion of the grid holder is referred to as A metalizing surface is formed on an upper surface of the blocking capacitor, and the remaining portion is formed of an inner and outer plate and a bottom plate connecting the inner and outer plates, and a metal cap having a height higher than that of the inner tube is assembled. An end portion of the outer plate is assembled to overlap the metalizing surface, the blocking capacitor of the microwave oven tube for microwave oven, characterized in that the heater housing extends from the upper end of the inner plate to the discontinuous surface.

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