JPH0371542A - Cathode-ray tube - Google Patents

Abstract

PURPOSE:To prevent a conductive film from peeling off so as to obtain a stable image by applying a conductive film to the inside of the funnel of a cathode-ray tube except for a nipple portion and near the inside portion of an anode button terminal placed across both sides of the nipple portion. CONSTITUTION:A conductive film 2 is applied to the inner wall surface of the funnel 1 of a cathode-ray tube, except for the inside portion of an anode button terminal 4 provided on the inner wall surface, a nipple portion 5 and near the inside portion of the terminal. Thus, a high voltage applied to the terminal 4 is transmitted and supplied to the whole of the film 2 by the contact of a getter supporting metal plate 6 with the film 2, the plate 6 extending from the nipple portion 5. The film 2 is prevented from peeling off due to the contact and vibration of the junction point of the nipple portion 5 with the metal plate 6 and the withstand property of the cathode-ray tube is enhanced whereby a stable image is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to cathode ray tubes, and more particularly to improvements in the application of conductive coatings to funnels.

[Conventional technology]

3 and 4 are a cross-sectional view and a perspective view showing the structure of a conventional getter installation for a cathode ray tube disclosed in, for example, Japanese Unexamined Patent Publication No. 60-221941. In the figures, 9 is a conductive coating 8 on the inner surface. 10 is an anode phase terminal embedded in the funnel portion 9, and 11 is a nipple portion of the anode phase terminal 10 that projects inside the tube. Reference numeral 12 denotes a metal plate for supporting a getter, which has a getter 13 at its tip and is attached to the nipple portion 11.

The partial side sectional view of FIG. 2 shows the detailed state of application of the conductive coating 8, and the conventional conductive coating 2 is also applied to the inside of the anode S port terminal 4 and the nipple portion 5. I understand that.

Next, the operation will be explained using FIG. 2.

In order for an anode ray tube to operate, a high voltage must be supplied from the anode phase terminal 4 to either the electron gun or the phosphor screen, and in order to supply the high voltage, a high voltage must be applied to the conductive coating 2. It is necessary to establish electrical conduction, and conventionally, a high voltage applied from the anode terminal 4 was applied to the inner side of the anode phase terminal 4 and the nipple portion 5 to establish electrical conduction through the conductive coating 2 to the entire coating.

[Problems to be Solved by the Invention] In conventional conductive coating treatment on the inner wall surface of the funnel of a cathode ray tube, since the coating is applied to the entire inner wall surface, the bonding between the nipple portion 5 and the metal plate 6 for supporting the getter is difficult. The conductive coating applied to the inside of the funnel and nipple of the anode button terminal 4 may peel off due to point contact or vibration, causing sparks or electrical leakage within the tube during operation of the charged anode ray tube. There was a problem.

This invention was made to solve the above-mentioned problems, and its purpose is to obtain a cathode ray tube that has excellent high voltage characteristics without peeling off the conductive coating applied to the inner wall surface of the funnel. do.

[Means to solve the problem]

In this invention, a conductive coating is applied to the inner wall surface of the funnel of a cathode ray tube, except for the nipple portion and the vicinity of the inner side of the anode button terminal on both sides thereof.

[Function] In this invention, a conductive film is applied to the inner wall surface of the funnel of the cathode ray tube, except for the inner side of the anode button terminal, the nipple part, and the vicinity of the inner side of the anode button terminal on both sides. There is no peeling off of the conductive coating due to contact with metal plates, etc., and excellent withstand voltage characteristics can be maintained.

〔Example〕

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

FIG. 1 is a partial configuration diagram of a cathode ray tube according to an embodiment of the present invention.

In the figure, the same reference numerals as in the conventional example indicate the same parts, and the conductive coating 2 is located on the inner side of the anode button terminal 4, on the nipple part 5. The area near the inside of the anode button terminal 4 is not coated.

The high voltage applied to the anode button terminal 4 is electrically conductive through contact between the getter supporting metal plate 6 coming out of the nipple portion 5 and the conductive film 2, and is supplied to the entire conductive film 2.

As described above, in this embodiment, the anode phase terminal 4. Nipple part 5
．． Since the coating is not performed near the inner side of the anode button terminal 4, there is no possibility of peeling off of the conductive coating 1fII2 due to contact at the junction between the nipple portion 5 and the getter supporting metal plate 6, vibration, or the like. Furthermore, the conduction of the high voltage applied from the anode button terminal 4 was conducted through the conductive coating 2 on the nipple part of the anode button terminal 4 in the past.
Electrical conduction occurs due to contact between the getter support metal plate 6 connected to the nipple portion 5 of the conductive coating 2, and a stable high voltage is conducted to the electron gun and phosphor screen, thereby improving the high voltage stability of the cathode ray tube. can be kept.

〔Effect of the invention〕

As described above, according to the cathode ray tube of the present invention, the conductive coating is applied inside the funnel except for the nipple portion and the vicinity of the inner side of the anode button terminal on both sides thereof. Even if there is contact or vibration at the junction with the conductive film, the conductive film will not peel off, and therefore, there will be no sparks or electrical leakage from the electron gun, and a stable image can be obtained.

[Brief explanation of drawings]

FIG. 1 is a partial configuration diagram of a cathode ray tube according to an embodiment of the present invention, FIG. 2 is a diagram showing the state of application of a conventional conductive film, and FIGS. They are a sectional view and a perspective view. In the figure, 1 is a funnel part, 2 is a conductive coating, 3 is a getter, 4 is an anode button terminal, 5 is a nipple, 6 is a metal plate for supporting the getter, and 7 is an extension of the metal plate for supporting the getter. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] (1) In a cathode ray tube having a conductive coating on the inner wall surface of the funnel, the conductive coating is coated on the inner wall surface of the funnel except for the nipple portion and the vicinity of the inner side of the anode button terminal on both sides thereof, and the cathode button terminal The high voltage applied is made conductive through contact between the getter supporting metal plate connected to the nipple inside the anode button terminal and the conductive coating coated on the inner wall surface of the funnel. Cathode ray tube.