JPS59171433A - Electron gun for color picture tube - Google Patents

Abstract

PURPOSE:To improve color defocusing and dispersion thereof by fixing both ends of the first control electrode to a hermetic support. CONSTITUTION:Total of four end segments 11a extending to the lower side of electron gun in the edge side of bead support 11b, two each in both sides, are formed to the first control electrode 11. The hermetic support 12 is provided with the end segment 12a at the edge and a bead support 12b at the center and a cut part 12d with stepped portion is formed on the cup part 12c. The width l2 of short side of cup part 12c is almost equal to the width l1 between edge segment 11a of the first control electrode 11. After, the first control electrode 11 and hermetic support 12 are fixed by welding to a bead glass support body 8 with a specified interval, the edge segment 11a of first control electrode 11 is fixed by welding to the side surface of the cup part 12c of hermetic support 12 at the welding point 13 indicated by a cross mark.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an electron gun for a color cathode ray tube, and particularly to an improvement of a first control electrode.

[Background of the invention]

In general, an electron gun for a color cathode ray tube consists of three electron guns each made up of a plurality of grid electrodes, and the electron beam is focused by a main lens formed by the electron guns, and the electron beam is made to strike a screen. be.

FIG. 1 shows a conventional electron gun for color cathode ray tubes. A first control electrode 1 that has three holes through which the electron beam passes and controls the amount of the electron beam; and a first control electrode 1 that has holes on the same straight line as the three holes of the first control electrode 1 and that controls the electron beam emission direction. A first accelerating electrode 2, a second accelerating electrode 3, a third accelerating electrode 4, a fourth accelerating electrode 5, a fifth accelerating electrode 6 arranged in sequence, and a first accelerating electrode disposed before the first control electrode 1. The control electrode 1 is provided with three cathode electrodes 7 arranged in parallel in the horizontal direction, facing each of the three holes, and these electrodes 1 to 7 are welded and fixed to a bead glass support 8 and are integrally formed. It has become.

As shown in FIG. 2, the first control electrode 1 has a tab 1a for electrical conduction fixed by welding on the end side, and a bead support part 1b fixed by welding to the bead glass support 8 in the center part. Two pieces are formed.

As shown in FIG. 3, the three cathode electrodes 7 are attached to a fourth hermetic sabot 9 formed by bending a piece of plate metal.
It is fixed via a hermetic assembly electrode 10 shown in the figure. That is, the hermetic assembly electrode 10 is formed by welding and fixing three eyelets 10a to glass 10b, and the cathode electrode 7 is welded and fixed to the eyelets 10a. The hermetic support 9 has an end piece 9a at the end.
has a bead support portion 9b in the center, and the end piece 9
The hermetic assembly electrode 10 is welded and fixed to a, and the bead support portion 9b is welded and fixed to the bead glass support 8.

By the way, 1. In such a conventional electron gun, as described above, the first control electrode 1 is connected to the bead support section 1 provided at the center.
Since the cathode ray tube is supported by the central portion b, it tends to deform using the central portion as a fulcrum due to thermal doming caused by the heater during operation of the cathode ray tube. That is, the IC or 1d shown in Fig. 5 is deformed, and the tab 1a causes the cathode current of the three electron guns for red, blue, and green to change in a few minutes after ignition of the heater. This has disadvantages such as irregularities in color, color shift in the color cathode ray tube, and large variations in color shift.

[Purpose of the invention]

An object of the present invention is to provide an electron gun for a color cathode ray tube that can improve color shift and variations thereof.

[Summary of the invention]

The present invention is characterized in that both ends of the first control electrode are fixed to a hermetic support.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. Note that the same members as in FIG. 1 are given the same reference numerals, and their explanations will be omitted. As shown in FIG. 7, the first control electrode 11 has
A total of four end pieces 11a are formed on the end side of the bead support part 11b, two on each side, extending downward from the electron gun. Two end pieces 11a may be formed only on one side. As shown in FIG. 8, the hermetic support 12 has end pieces 12a at the ends, a bead support section 12b at the center, and a stepped cup section 12d formed on the cup section 12C. Further, the short side width 12 of the cup portion 12C is formed to be approximately equal to the width l between the end pieces 11a of the first control electrode 11.

Next, the assembly will be explained. As shown in Figure 6, the first
After welding and fixing the control electrode 11 and the hermetic support 12 to the bead glass support 8 at a predetermined interval, the end piece 11a of the first control electrode 11 is welded to the side surface of the cup portion 12c of the hermetic support 12 at a welding point 13 indicated by an X mark. Fix by welding.

In this way, the first control electrode 11 is supported by the hermetic support 12 by the end piece 11a, so both end holes of the first control electrode 11 are supported, increasing mechanical strength.
The three holes have uniform strength. Therefore, the deformation of the three holes of the first control electrode 11 in the electron gun axis direction due to heater heat during operation of the color cathode ray tube is reduced, the difference in cathode current of the three electron guns is reduced, and the degree of color shift is reduced. Become good.

Furthermore, since there are no tabs, the non-uniformity of hole deformation due to the presence of tabs is also eliminated, and the degree of color shift is improved.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, 5- Since both ends of the first control electrode are fixed to the hermetic support, both end holes are supported, tabs are not required, and color cathode ray tubes are Color shift and its variations at the start of operation are improved.

[Brief explanation of drawings]

Figure 1 is a front view of essential parts of a conventional electron gun for color cathode ray tubes, Figure 2 is a perspective view of the first control electrode in Figure 1, Figure 3 is a perspective view of the hermetic support in Figure 1, and Figure 4. 1 is a perspective view of the hermetic assembly electrode of FIG. 1, FIG. 5 is a simulated diagram of thermal deformation of the first control electrode, and FIG. 6 is a front view of essential parts showing an embodiment of the electron gun for a color cathode ray tube according to the present invention. , FIG. 7 is a perspective view of the first control electrode of FIG. 6, and FIG. 8 is a perspective view of the hermetic support of FIG. 6. 7... Cathode electrode, 11... First control electrode, 11a... End piece, 12... Hermetic support, 13... Welding point. Agent Patent Attorney Akio Takahashi 61 Figure 2 Figure 5 [1; Wide ≧)〈o6 1p-7, 4C Figure 7

Claims (1)

[Claims] A collar for connecting a first control electrode having a hole through which the electron beam passes and controlling the amount of the electron beam, a cathode electrode arranged in front of the first control electrode, and a hermetic support for holding the cathode electrode. An electron gun for a color cathode ray tube, characterized in that both ends of the first control electrode are fixed to the hermetic support.