JPS61195547A - X-ray shielding device - Google Patents

Abstract

PURPOSE:To improve the efficiency of producing an X-ray shielding device which restricts the amount of X-ray radiation to below a given level by shielding an anode contact from X-rays by affixing an X-ray shielding parts an insulating sheet which has an opening corresponding to the anode contact and also has an annular projection in its periphery. CONSTITUTION:Annular X-ray shielding parts 24a and 24b made of a lead tape are affixed to an insulating sheet 23 having an annular projection 27 in its periphery thereby producing an X-ray shielding device. The thus produced device is then affixed to an anode contact part in such a manner as to make an anode contact 20 face the opening of the device. Due to the above structure, the annular projection 27 prevents high voltage from leaking through the X-ray shielding parts 24a and 24b. Furthermore, it is possible to make the anode contact 20 to be shielded from X-rays during the preliminary process for producing CRTs.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an X-ray shielding device for a cathode ray tube anode portion of a projection type video projector.

BACKGROUND OF THE INVENTION In recent years, in projection type video projectors, in order to obtain a high-brightness screen, the voltage applied to the anode section (hereinafter referred to as "anode section") of a cathode ray tube, that is, the anode voltage, has been increased. Cathode ray tube (hereinafter referred to as rcR)
(denoted as TJ) J: The amount of radiated xi increases, necessitating an X-ray shield, and various X-ray shielding measures are being taken.

Regarding an example of such a conventional X-ray shield device, see Part 3.
This will be explained using FIGS. In Figure 3, 1 is C
RT anode contact part, 2 is CRT cone part, 3
is an anode cap, 4 is an X-ray shielding member made of lead tape, 5 is an insulating adhesive such as silicon bond,
This insulating adhesive 5 is for blocking high voltage leakage current from the CRT anode voltage to the X-ray shield member 4.

6 is a CRT face.

In the above X-ray shield device, the X-ray shield member 4
for pasting around the outside of the CRT. As mentioned above,
Since high voltage leakage occurred in the anode contact portion 1, the X-ray shield member 4 could not be attached, and the area around the anode cap 3 was not provided with an X-ray shield. While the anode voltage is still not very high, the conventional configuration can sufficiently reduce the amount of X-ray radiation below the specified value, and
This was an effective countermeasure because it was only necessary to attach an X-ray shielding member 4 such as lead tape to the CRT, and the work could be easily carried out in the CRT preparation process.

However, as the anode voltage has become higher due to the demand for high-brightness screens, the amount of X-ray radiation from the anode cap has increased, and it has become impossible to keep the voltage below the specified value with the above-mentioned conventional configuration.

Therefore, as shown in Fig. 4, an X-ray shield case 7 is installed to enclose the anode cap 3, and the entire periphery of the CRT is shielded, or as shown in Fig. 5,
A measure is taken to reduce the amount of X-ray radiation below a specified value by using an X-ray shielding device configured to house three CRTs in an iron case 8. In Fig. 4, 9 is an anode lead, 10 is a CRT mounting bracket, 11.12 is a soldering part, and in Fig. 5, 13 is a hole for the CRT neck part, and 14 is an anode cap X-ray shield iron. It's a cover.

Problems to be Solved by the Invention However, in the configurations shown in FIGS. 4 and 5 as described above, it is necessary to attach the X-ray shield device after attaching the anode cap 3, which causes problems in the CRT preparation process. Since the X-ray countermeasures cannot be completed and must be carried out during the assembly process, work efficiency is greatly reduced.Furthermore, in the method shown in FIG. Efficiency decreases in terms of man-hours as well, such as attaching. On the other hand, in the configuration shown in Figure 3, the X
Although the countermeasures against X-rays from the CRT anode are incomplete, the workability is good.
The problem was that line countermeasures could not be taken.

The present invention solves the above-mentioned problems, and aims to provide an X-ray shielding device that can complete X-ray countermeasures in the CRT preparation process, has good workability, and can sufficiently shield the anode section from X-rays. purpose.

Means for Solving the Problems In order to solve the above-mentioned problems, the X-ray shielding device of the present invention has an opening in the center corresponding to the anode contact of the cathode ray tube and an annular protrusion on the outer periphery. and an annular X-ray shield member attached to a portion of the insulating sheet surrounded by the annular protrusion.

Effects According to the above configuration, even if the anode voltage becomes high, the amount of X-ray radiation can be suppressed to a specified value or less, and X-ray countermeasures can be completed at the CRT preparation stage, resulting in extremely high work efficiency.

Example An embodiment of the present invention will be described below with reference to FIG.

FIG. 1A is a cross-sectional view of an X-ray shield device according to an embodiment of the present invention attached to a CRT anode section, and FIG. 8 is a cross-sectional view of the same X-ray shield device.
21 is the anode contact part of the CRT, 21 is the CRT cone part, 22 is the anode cap, 23 is an annular insulating sheet made of synthetic resin made of silicone, etc., 24 is an X-ray shielding member made of lead tape, etc., 25 is silicon bond 26 is an aperture, and 27 is an annular protrusion formed on the outer periphery of the insulating sheet 23. An X-ray shielding member 24 such as a lead tape pasted on an insulating sheet 23 has an annular protrusion 27 as a partition, and an annular X-ray shielding member 24a on the inner side and an annular X-ray shielding member on the outer side.
The wire shield member 24b is separated from the wire shield member 24b.

The effects of the above configuration will be explained below.

In the above X-ray shield device, since the anode contact portion 20 and the frontage portion 26 are attached to the anode contact portion 20 in correspondence with each other, high pressure leakage due to the X-ray shield members 24a and 24b separated by the annular protrusion 27 is prevented. and anode contact part 2 in the CRT preparation process.
0 can be provided with an X-ray shield.

As described above, according to this embodiment, the annular protrusion 27 is provided on the outer circumference.
An annular X-ray shielding member 24a, 24b made of lead tape or the like is attached to the insulating sheet 23 on which the anode contact part is constructed. High pressure leaks can be completely prevented without any coating.

FIG. 2 shows another embodiment in which the annular protrusion 28 is formed with an inverted triangular cross section to more completely prevent high pressure leaks.

Although not shown, an insulating sheet 23 and X-ray shield members 24a, 2 are provided so that they can be easily attached to the curved surface of a CRT.
If an acute-angled cut is provided in 4b by forming a triangular notch with the apex at the center of the opening 26, workability can be further improved.

Effects of the Invention As described above, according to the present invention, an X-ray shield 71 member is adhered to an insulating sheet having an opening corresponding to an anode contact portion and an annular protrusion on the outer periphery. Since the anode contact portion is thereby shielded from X-rays, the number of X-rays rJJ can be suppressed to below a specified value, and at the same time, workability can be greatly improved.

[Brief explanation of the drawing]

FIG. 1A is a sectional view of an X-ray shield device according to an embodiment of the present invention attached to a CRT anode, FIG. 1B is a sectional view of the same X-ray shield device, and FIG. 3 is a schematic plan view of a CRT equipped with a conventional X-ray shielding device, and FIG. 4A is a side view of a CRT equipped with another conventional X-ray shielding device. 8 is a perspective view of the same external appearance, and FIG. 5 is a perspective view of the external appearance of yet another conventional X-ray shield device. 20... Anode contact portion, 23... Insulating sheet, 24, 24a, 24b... X-ray shield member, 26... Opening portion, 27... Annular protrusion portion Yoshihiro Morimoto Figure 3 Figure 4 Figure 5

Claims (1)

[Scope of Claims] 1. An insulating sheet having an opening in the center that corresponds to the anode contact portion of the cathode ray tube and an annular protrusion on the outer periphery; An X-ray shield device comprising an annular X-ray shield member affixed to a surrounded portion. 2. The X-ray shield device according to claim 1, wherein the insulating sheet and the X-ray shield member have an acute-angled cut with the apex at the center of the opening.