JPS61140036A - Cathode-ray tube - Google Patents

Abstract

PURPOSE:To prevent cracking of glass from being produced in the vicinity of an anode button owing to contact insertion by mounting a heat resistant protector higher in insulation resistance and a peripheral surface of the anode button of funnel glass. CONSTITUTION:A heat resistant protector 22 higher in dielectric strength is bonded onto a surface of funnel glass 3 around an anode button 5 by means of an adhesive 23 having the same property as the protector. In mounting a contactor for high-tension supply, a flaw due to glass is produced around the anode button 5 since a contactor is not brought into direct contact with the glass by providing the protector 22 as such, whereby the glass is prevented from being cracked.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cathode ray tube used in television receivers and the like, and more particularly to a cathode ray tube that prevents scratches around the 7-node button.

[Prior Art] FIG. 3 is a cross-sectional view schematically showing a conventional cathode ray tube,
In the figure, (1) is the cathode ray tube, (2) is the pulse section, (
3) is funnel glass, (4) is fan 2 glass (
The neck part connected to 3), (5) is the funnel glass (3
7 note hotane welded to ), (6) is the panel part (2
), (7) is a conductive film that takes four lines between the fluorescent screen (6) and the 7 note button (5), (8
) is an electron gun housed in the neck part (4), (9) is a conduction spring that constitutes a part of the electron gun (8), and (10) is a connection between the electron gun (8) and the anode button through the conduction spring (8). (5)
(11) is a metal vapor deposited film, (
12) is a lead electrically connected to the electron gun (8).

The cathode ray tube (1) shown in FIG.
By applying an appropriate voltage to each electrode of the electron gun (8) through 2) and further applying a high voltage of 10 to 30 KV to the anode button (5), images such as characters and images are displayed on the phosphor screen (6). is now available.

By the way, in order to apply high voltage to the 7-node button (5), as shown in Figure 4, insert the high voltage supply lead (13) into the anode button (5) and connect them electrically. Connecting. That is, since the contactor (14) connected to the high voltage supply lead (13) has appropriate elasticity, it can contact the 7-node button (5) and maintain proper electrical continuity between the two. There is.

FIG. 5 shows the state before the contactor (14) is inserted into the anode button (5). As can be seen from the figure, the tip size (15) of the contactor (14) is designed to be larger than the inner diameter (16) and opening (17) of the 7-node button (5), so when inserting the contactor, the contactor (14
) Using its own elasticity, apply a pressing force to the contactor (14) in the direction of the arrow so that the tip dimension (15) is smaller than the opening (17) of the 7-node button (5), and in this state press the anode button. (5). After insertion, by removing the pressing force, the contactor (14) expands within the anode button (5) due to its elasticity, and the anode button (
5) 91! Proper conduction can be obtained by contacting the two.

[Problems to be Solved by the Invention] The conventional cathode ray tube is constructed as described above, but when the contactor (14) is inserted into the anode button (5),
Anode button (5) and surrounding crow (18)
The tip of the contactor (14) comes into contact with the contactor (14), and as shown in FIG. 6, defects (18) such as scratches may occur on the crow (18) around the anode button (5).

It is generally well known that strain (internal stress) usually exists in the glass (18) around the anode button (5) that is welded to the funnel glass (3). The amount of this distortion is determined by the difference in expansion coefficient between the glass that makes up the funnel glass (3) and the metal that makes up the 7-node button (5), but if the ratio becomes thick, it may cause glass breakage. Therefore, the expansion coefficients of both have been carefully considered and designed to prevent this from happening. Therefore, usually
This distortion alone does not cause glass cracking.

However, in FIG. 3, the cathode ray tube (1)
When the inside of the tube (21) of J becomes a vacuum, atmospheric pressure causes distortion that deforms the entire cathode ray tube. Such distortion is called vacuum deformation distortion, and depending on the shape of the cathode ray tube, quite large distortion may occur at specific locations.

If this vacuum deformation strain becomes large and is added to the strain of the glass (18) around the anode button (5), even a small scratch may cause the glass to break. This situation is shown in FIG. 7, where glass cracking (20) usually occurs from the boundary with the anode button (5) where the strain is at its maximum. When such glass cracking (20) occurs, the cathode ray tube (1) loses its vacuum tightness, leading to a serious problem in which its function stops.

Therefore, the glass (1) around the 7 node button (5)
8) A cathode ray tube that produces large distortions, including vacuum deformation distortion (
In 1), efforts were made to prevent defects such as scratches as much as possible, but defects (19) caused by contact with the contactor (14) as described above cannot be prevented by the efforts of the cathode ray tube manufacturer alone. However, the reality is that it is not effective against extremely diverse users.

This invention was made to eliminate the above-mentioned conventional drawbacks, and an object thereof is to provide a cathode ray tube that does not cause glass breakage due to defects such as scratches.

[Means for Solving the Problems] According to the present invention, a heat-resistant and high electrical dielectric strength protector is attached to the surface of the funnel glass around the anode button.

[Function] In this invention, even if the contactor comes into contact with the area around the 7 note button, the contactor does not come into direct contact with the glass due to the presence of the protector, so the glass around the anode button will not be scratched. The occurrence of cracks is prevented.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of a cathode ray tube according to the present invention. In FIG. 1, the same or equivalent parts as in FIGS. 3 to 5 are given the same reference numerals. Fanol glass (
A heat-resistant and high electrical dielectric strength protector (22) is adhered to the surface around the 7-node button (5) in 3) with an adhesive (23) having similar properties. A silicone sheet is generally used as the protector (22), and silicone cement is generally used as the adhesive (23).

By providing such a protector (22),
When inserting the contactor (14), contactor (14)
Since the button 4) does not come into direct contact with the glass, the glass scratches around the 7-node button (5) will be collected, and therefore the glass will not break.

Note that the protector (22) is not necessarily a sheet, but may be a solid material, and its material may also be organic, sulfur, etc.
No matter the occasion. The same applies to the adhesive (23).

[Effects of emitting J] As described above, according to the present invention, it is possible to eliminate the occurrence of glass scratches around the anode button and prevent glass breakage, thereby making it possible to create cathode ray tubes that can be used with confidence by a wide variety of users. There is an effect that can be provided.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an embodiment of the cathode ray tube according to the present invention, Fig. 2 is a front view thereof, Fig. 3 is a sectional view showing a conventional cathode ray tube, and Fig. 4 is a 7-made button in Fig. 3. FIG. 5 is a sectional view showing the contactor inserted into the 7-node button in FIG. 3, and FIG. FIG. 7 is a front view showing the state of occurrence of glass cracking in a conventional cathode ray tube. (1)...Cathode ray tube, (3)...Funnel glass, (5)...Anode button, (22)...Protector. In addition, in the figures, the same reference numerals are the same -t or corresponding parts are A j
, .

Claims (2)

[Claims] (1) A cathode ray tube in which a funnel glass is provided with an anode button for applying high voltage, characterized in that a heat-resistant and high electrical dielectric strength protector is attached to the surface around the anode button of the funnel glass. cathode ray tube. (2) A cathode ray tube according to claim 1, wherein the protector is bonded with an adhesive having similar properties.