KR20020034577A - A cathode housing of microwave oscillator for microwave oven - Google Patents

Abstract

PURPOSE: A cathode housing of an SHF(Super High Frequency) oscillator tube for microwave oven is provided to improve a characteristic of an input cavity by assembling easily a cathode flange and a cathode housing with one body. CONSTITUTION: A cathode support portion(210a) has a cylindrical shape. The cathode support portion(210a) is fixed to an upper face of a cathode. A cathode flange portion(210b) is formed by extending the cathode support portion(210a) to a horizontal direction. An input cavity(105) is a space surrounded by the first grid(101), the first grid holder(204) for supporting the first grid(101), a cathode housing(210) including a cathode support portion(210a) and a cathode flange portion(210b), and a blocking capacitor(104). The input cavity(105) is oscillated nearly to an oscillation frequency. An interval between the first grid holder(204) and the second grid holder(206) is maintained by a spacer(205). The second grid holder(206), the spacer(205), the first grid holder(204), the blocking capacitor(104), and the cathode housing(210) are combined by a bolt(203).

Description

A cathode housing of microwave oscillator for microwave oven

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cathode housing of a microwave oven tube for microwave oven, and more particularly, to a cathode housing in which a cathode flange and a cathode housing are integrally assembled to facilitate assembly, and to improve characteristics of an input cavity.

Conventional ultra-high frequency oscillation tube is typically, as shown in Figure 1, a ring-shaped cathode 106 that functions as an electron radiator is disposed on the heater 107, about 600 ~ by indirect heating of the heater 107 When heated to 1200 ° C, hot electrons are released from the cathode. By applying a bias voltage to the first grid 101 arranged above the cathode 106 at a distance from the cathode 106, the hot electrons emitted from the cathode 106 are focused on the input cavity 105.

The hot electrons focused on the input cavity 105 are density-modulated by the automatic shielding function of the bias power supply of the first grid 101 and pass through the first grid 101. In this case, when an operating voltage is applied between the input cavity and the output cavity 105 and 103 insulated from each other, a potential difference is generated therebetween, so that hot electrons passing through the first grid 101 are accelerated to pass through the second grid 102. Therefore, surface current is induced to the output cavity 103. As a result, microwaves are formed in the output cavity 103, and the microwaves are radiated through the antenna 110 formed in the output cavity 103 through the center of the anode 109.

For this purpose, the coupling end 108 of the antenna 110 is located in the output cavity 103, and at the center between the input and output cavities 105, 103, a part of the microwave formed in the output cavity 103 is input. A feedback rod 111 that feeds back to the cavity 105 is installed to amplify and resonate the power of the microwave.

In FIG. 2, which is an enlarged detail of the portion A of FIG. 1, the input cavity 105 includes a first grid holder 204, a cathode housing 201, a cathode flange 202, and a blocking supporting the first grid 101. It is formed into a space enclosed by the capacitor 104. In addition, the input cavity 105 is designed to resonate near the oscillation frequency, and when resonating, the voltages applied to the input cavity 105 and the output cavity 103 are insulated from each other, and the ultra-high frequency current is transmitted to the first grid holder 204. , The inner surface of the cathode flange 202 and the cathode housing 201 flows.

The cathode flange 202 is press-fitted near the middle of the cathode housing 201 and welded, and the first grid holder 204 and the second grid holder 206 disposed on the top of the blocking capacitor 104 are spacers 205. Spacing is maintained. In this state, the bolt 203 has a second grid holder 206, a spacer 205, a first grid holder 204, a blocking capacitor 104, and a cathode flange 202 from the top, as shown in FIG. 2. Fasten.

However, since the cathode housing of a conventional microwave microwave tube for a conventional microwave oven as described above is welded after the cathode flange is inserted near the middle of the cathode housing 201, the cathode flange that is in contact with the cathode when the cathode is thermally expanded at high temperature is also welded. It expands, and its assembly state changes to deform the shape of the input cavity. As a result, the flow of the surface current forming the microwave causes a change in the contact surface, which adversely affects the input cavity resonance characteristics.

Accordingly, the present invention provides a cathode housing in which the contact surface between the cathode flange and the cathode housing is removed so that the resonance mode of the input cavity is not changed by preventing the shape change of the input cavity due to shrinkage and expansion of the cathode flange. It aims to do it.

1 is a cross-sectional view showing the structure of an ultra-high frequency oscillation tube used as a conventional microwave microwave oscillation tube.

2 is a partial cross-sectional view of a microwave oven for microwave oven equipped with a conventional cathode housing.

Figure 3 is a partial cross-sectional view of the oscillating tube for a microwave oven equipped with a cathode housing according to an embodiment of the present invention.

(Explanation of symbols for the main parts of the drawing)

101: first grid 102: second grid

103: output cavity 104: blocking capacitor

105: input cavity 106: cathode

107: heater 108: coupling end

109: anode 110: antenna

111: feedback rod 201: cathode housing

202: cathode flange 203: coupling bolt

204: first grid holder 205: spacer

206: second grid holder 210: cathode housing

210a: cathode support 210b: cathode flange

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

Figure 3 is a partial cross-sectional view of the oscillation tube for a microwave oven equipped with a cathode housing according to an embodiment of the present invention, the present invention is a cylindrical cathode support that is fixed to the upper surface to accommodate the cathode by extending horizontally in one side; It is formed of a cathode flange portion 210b integral with the cathode support portion 210a and extending horizontally outward.

In addition, the input cavity 105 includes a first housing 101, a first grid holder 204 supporting the first grid, a cathode housing 210 composed of a cathode support 210a and a cathode flange 210b, and blocking. It is formed into a space enclosed by the capacitor 104. The input cavity 105 is designed to resonate near the oscillation frequency, and when resonating, the voltages applied to the input cavity 105 and the output cavity 103 are insulated from each other, and the surface current is applied to the inner surface of the input cavity 105. Flow.

The first grid holder 204 and the second grid holder 206 are spaced apart by the spacer 205, and in this state, the bolt 203 is moved from the top to the second grid holder (as shown in FIG. 3). 206, the spacer 205, the first grid holder 204, the blocking capacitor 104, and the cathode housing 210 are fastened.

As described above, the cathode housing of the microwave microwave tube for microwave oven of the present invention has no change in the shape and dimensions of the input cavity according to the change of the assembly state when the cathode is heated and expanded, so that the surface current of the input cavity is seamless. Reduces the amount of microwaves fed back from the output cavity to the input cavity, which reduces the amount of microwaves from the output cavity to the overall oscillator tube, allowing for smooth flow along the surface of the housing, improving input cavity resonance characteristics, ease of assembly, and reducing the loss of microwaves in the input cavity. To increase the efficiency.

Claims (1)

In the cathode housing of a microwave oven tube for microwave oven, wherein the first grid, the first grid holder supporting the first grid, the cathode housing and the blocking capacitor form an input cavity, A cylindrical cathode support portion accommodating the cathode by horizontally extending one side inward and fixed to an upper surface of the cathode, and a cathode flange portion integrally formed with the cathode support portion and horizontally extending outwardly in the vicinity of the cathode support portion; Cathode housing