KR200147987Y1 - Pellet supporting structure of impregnation type cathode - Google Patents

Abstract

The present invention discloses a novel structure for supporting pellets of impregnated cathodes.

In order to prevent deterioration of electron emission efficiency due to oxidation of the pellets by direct welding of the pellets, in the present invention, a tab is formed on the upper end of the inner sleeve and fixed by bending the tab toward the pellets located on the partition wall.

Such a structure not only facilitates the assembly of the cathode but also does not use welding, so that the oxidation of the cathode is fundamentally prevented.

Description

Pellet Support Structure of Impregnated Cathode

1 is a cross-sectional view showing the configuration of a cathode ray cathode.

2 (a) and 2 (b) are cross-sectional views showing a conventional pellet support structure.

Figure 3 is an exploded perspective view showing an embodiment of the support structure of the present invention.

4 is a cross-sectional view of the coupling state thereof.

5 (a) and 5 (b) are perspective views showing another embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

1: inner sleeve B: diaphragm

1: pellet 2,2 ': tab

3: notch

The present invention relates to a CRT, and more particularly to a pellet support structure of a dispensing type cathode.

The cathode ray tube, which is the main application field of the present invention, forms an electron beam by focusing and accelerating the thermal electrons generated at the cathode by a plurality of control electrodes, and deflects the electron beam. By selectively emitting each part of the device, a device is configured to scan and display an image. Here, a configuration of a cathode serving as a hot electron emission source is shown in FIG. 1, wherein a heater (H) is housed inside an inner sleeve (I), and an electron emission source is disposed at an upper end thereof. A cup (C) containing a pellet (P) of the negative electrode material is installed (this is the case of an impregnated cathode and an oxide material coated cap). .

The inner sleeve (I) is made of a thin metal ribbon on an outer sleeve (O) supported by a support (S) on the strap (A) to prevent heat dissipation and consequent heat loss. ribon; B).

On the other hand, the heater (H) is generally composed of a double winding coil, and the coating layer (D) is formed on the surface thereof by electrodeposition or the like, and the lead (L) is connected to the heater tab (T). Connected to an external circuit.

An impregnated cathode, also called a storage cathode, impregnates a cathode material in a porous sintered body formed by tungsten or the like to form pellets (P) to support the inner sleeve (I).

2 shows a general support structure for such pellets P. As shown in FIG. First, the structure of FIG. 2 (a) is a structure in which the pellet P is accommodated in the cup C and inserted into the end of the inner sleeve I to be welded like an arrow.

On the other hand, the structure of FIG. 2 (b) is configured to attach the partition B into the inner sleeve I without inserting the cup C, insert the pellet P thereon, and weld it from the side as shown by the arrow. to be.

All of these support structures directly weld the pellets P to the inner sleeve I or the cup C, so that the tungsten and the negative electrode material in the pellets P are oxidized by the high heat during welding. As a result, the temperature distribution and electron emission in the pellets P become non-uniform, resulting in a problem of lowering the electron emission efficiency.

In addition, the conventional structure in which the cup (C), the partition (B), etc. are installed in the inner sleeve (I) having a diameter of only 2 or 3 mm and the pellet (P) is welded is difficult to precisely adjust, resulting in many defects and a high yield. There is also a problem that is not high.

In view of such a conventional problem, an object of the present invention is to provide a pellet support structure which is extremely easy to assemble and does not have a thermal effect such as oxidation on the pellet.

In order to achieve the above object, the pellet support structure according to the present invention extends a tab on the upper end of the inner sleeve, and attaches a partition wall to restrict the entry of pellets into the upper side of the inner sleeve. It is characterized in that the pellets are bent inwardly while the pellets are inserted and supported therein to fix the pellets.

According to a preferred feature of the present invention, the upper part of the pellet is chamfered in a truncated cone shape, wherein the tab is configured by forming a plurality of V-shaped notches on the upper end of the inner sleeve.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In FIG. 3, the partition B is attached to the inner side of the inner sleeve I as shown in FIG. 2B so as to restrict the insertion of the pellet 1 so as to be inserted at an appropriate position. An upper end of the inner sleeve I is preferably provided with a plurality of tabs 2 which are bent inward when the pellet 1 is inserted to fix the pellet 1.

At this time, the upper portion (1a) of the pellet (1) is preferably chamfered, that is, chamfered in a conical shape for convenience of fixing.

This pellet support structure is fixed to the pellet 1 by placing the pellet (1) on the partition (B) in the inner sleeve (I) and then bending the tab (2) inward as shown in the fourth back. In this case, when the upper portion 1a of the pellet 1 is formed in a truncated cone shape, the pellet 1 may be fixed without being detached by the support of the tab 2.

According to this structure, since welding is not necessary for the support of the pellet 1, not only problems such as oxidation of the pellet 1 are generated, but also the manufacturing process becomes extremely easy.

However, in such an embodiment, since the tab 2 partially supports the circumference of the pellet 1, there is a possibility that arc or stray emission may occur in some cases.

Accordingly, in the embodiment of FIG. 5, as shown in (a), the V-shaped notch 3 is formed at the upper end of the inner sleeve I so that the portion between each notch 3 forms the tab 2 '. do. When each tab 2 'is bent inwardly, each tab 2' is in close contact with the upper portion 1a of the cone-shaped pellet 1 as shown in FIG. 5 (b) to form a conical continuous surface.

In this embodiment, when the extension line of the lower end of the notch 3 becomes the bending line of the tab 2 ', the depth and the cutting angle of the notch 3 correspond to the shape of the upper portion 1a of the pellet 1.

As such, according to the present invention, the welding process is unnecessary to fix the pellet 1, so that the assembly of the cathode is easy and stable electron emission characteristics can be maintained.

Accordingly, there is a great effect of improving the characteristics and reliability of the CRT of the present invention, manufacturing cost, and productivity.

Claims (3)

In the structure for supporting the pellet of the impregnated cathode to the inner sleeve, the partition (B) for restricting the entry of the pellet (1) is attached to the inner upper portion of the inner sleeve (I), the inner sleeve ( The tabs 2 and 2 'are extended on the upper end of I), and the tabs 2 and 2' are bent inward in the state where the pellet 1 enters the partition B. Impregnated cathode pellet support structure. The pellet support structure according to claim 1, wherein the upper portion (1a) of the pellet (1) is formed in a cone shape. The pellet support structure according to claim 1, wherein the tab (2 ') is formed by forming a plurality of V-shaped notches (3) on the upper end of the inner sleeve (I).