JPH01115029A - Manufacture of cathode-ray tube - Google Patents

Abstract

PURPOSE:To improve the reliability of a cathode-ray tube after completion by immersing an electron gun electrode group without any built-in part in an insulation solution for knocking treatment, then constituting an electron gun after assembly, inserting and positioning the gun in a cathode ray tube body, and applying exhaust, getter cleaning and sealing treatment to the inside of the tube body. CONSTITUTION:Before assembling an electron gun into the tube body of a cathode-ray tube, knocking treatment applies to an electron gun electrode group 1 in an insulation solution 2 under the application of high voltage. The electrode group 1 is inserted in the tube body in a cleaning atmosphere in such a way as not to mark a finger print and deposit a dust and the like on other clean parts such as a cathode, a heater, a getter and furthermore lead systems 10 and 11 and the like sealed in the neck end of the tube body for a terminal lead from the required electrode of the electron gun. Thereafter, exhaust treatment applies to the inside of the tube body and a getter material is subjected to cleaning treatment. According to the aforesaid construction, the frequencies of field emission, stray emission, flashover and the like are reduced at the time of the operation of the cathode-ray tube. The cathode-ray tube of high reliability can be thereby obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing cathode ray tubes such as television picture tubes and terminal display devices.

[Summary of the invention]

The present invention involves performing a knocking treatment on the electron gun disposed inside the cathode ray tube body in an insulating liquid with the electron gun electrode group from the first grid onwards before the assembly is completed, so that the cathode ray tube after completion is Improve reliability.

[Conventional technology]

Normally, in a cathode ray tube, during operation, there is a reduction in the performance of the cathode ray tube due to a voltage drop due to floating electrons or discharge generated near the electron gun electrode, image disturbance, or even circuit failure due to discharge current. In order to avoid such occurrences, high-voltage treatment, so-called spot knocking, is carried out after the cathode ray tube is completed to prevent floating electrons or discharge. This spot knocking usually occurs during the assembly and manufacturing of cathode ray tubes, that is, the coating of phosphor on the inner surface of the panel of the cathode ray tube body, the housing arrangement of various parts such as electron guns, the exhaust treatment inside the tube, and the cathode rays caused by getter spit. After the tube is completed, a DC or AC pulsed high voltage of 1.5 to 3 times the maximum rated voltage during normal operation is applied between the required electrodes of the electron gun, especially the high voltage electrode where high voltage is applied. I will do it. To explain further, when manufacturing electron gun electrodes, scratches,
The manufacturing and assembly are performed with sufficient care to prevent the formation of protrusions, and care is taken to prevent dirt, such as fingerprints, from adhering. In addition, sufficient care has been taken during assembly to prevent dust from entering the cathode ray tube tube. However, dust may exist near the electron gun after exhaust. This is because phosphor powder, carbon powder, etc. that are electrostatically floating inside the tube or that are not firmly adhered to the tube are attracted, and this can cause discharge, but generally as mentioned above, It is said that if spot knocking is performed, this will be blown away and charged to a stable state, making it harmless. For color cathode ray tubes, the anode voltage is usually 25-28 KV, and for projection cathode ray tubes, it is 30-28 KV.
34KV, which is 10~
Since a considerably higher voltage than 15KV is applied, discharge is likely to occur during operation.

Therefore, in the case where the anode voltage during operation is high, the high voltage treatment after the exhaust treatment, that is, spot knocking, is also performed at a high voltage to remove foreign matter and protrusions on the electrodes by discharge. However, in the case of a metal electrode, when spot knocking is performed at a high voltage as described above, the energy thereof is so large that sputtering of the metal atoms constituting the electrode may occur. Therefore, there is a problem in that even if such no-spot knocking is performed at a sufficiently high voltage and for a sufficient period of time, foreign matter or protrusions may remain on the electrode as a result.

Also, during DC knocking or cathode ray tube operation,
Due to the charging of the neck tube in which the electron gun of the cathode ray tube body is housed, field emission (electron radiation) from foreign objects or protrusions on the electron gun electrode and stray emission (glow discharge) can be seen. If the field emission is strong, there is also the problem that it causes the Browning phenomenon in the neck tube, that is, deterioration of the glass of the neck tube.This stray emission (glossy discharge) is also a precursor phenomenon of so-called lightning strikes (flashover). Foreign matter and protrusions on the electrodes must be removed as much as possible.However, when performing spot knocking on a cathode ray tube after exhaust treatment as in the past, the foreign matter or protrusions on the metal electrodes are simply scattered within the tube. Yes, it follows that - only a temporal stable state is obtained.

[Problem that the invention seeks to solve]

The present invention solves various problems caused by foreign objects and protrusions on the electrodes in the above-mentioned method of performing spot knocking treatment after exhaust treatment of a normal cathode ray tube, and improves the anode voltage during operation of the completed cathode ray tube. To surely avoid the occurrence of field emission, stray emission, etc. even in a case where the emission is high.

[Means for solving problems]

As shown in FIG. 1, the present invention is directed to a cathode or a heater, which is disadvantageous due to its characteristics when immersed in an insulating liquid, which will be described later, a getter, and a lead lead-out sealed at the end of the neck of the finally obtained tube. The electron gun electrode group (1), which has no parts such as a lead stem through which a lead pin is penetrated, is impregnated in an insulating liquid (2), and in this state, the electron gun electrode group (1) is ) to perform knocking treatment by applying a predetermined high voltage to the required electrodes, and then assemble the cathode, heater, getter, electron gun lead stem, etc. to the electron gun electrode group (1) to configure the electron gun. This is inserted into the cathode ray tube body, and the tube body is subjected to exhaust treatment, getter spit treatment, and sealing treatment to obtain the intended cathode ray tube.

[Effect]

According to the above-mentioned method of the present invention, the knocking process for the electron gun is performed before the electron gun is incorporated into the cathode ray tube body, that is, outside the cathode ray tube body, so that the dust or electrodes removed by the knocking process are absorbed into the tube body. Remaining is avoided.

Therefore, the electrode group treated in this way is sealed in a clean open atmosphere with other clean components such as cathodes, heaters, getters, and also at the neck end of the tube body for leading out terminals from the required electrodes of the electron gun. By inserting the lead stem etc. into the tube 8 body to prevent fingerprints, dust, etc. from adhering, and by passing through exhaust treatment and spit treatment of getter material, knocking treatment after sealing of the tube body is performed. It was confirmed that the frequency of occurrence of field emissions, stray emissions, and frudge over during the operation of the cathode ray tube can be reduced more reliably than when the cathode ray tube is operated, and a highly reliable cathode ray tube can be obtained. Ta.

In addition, in the method of the present invention, the knocking process is performed by applying high voltage to the electron gun electrode group (1) in the insulating liquid (2), so that the knocking process does not cause oxidation of the electrode part or cause the discharge. Inconveniences such as melting could be avoided, and the occurrence of defective products could be avoided.

〔Example〕

For example, in the case of a unipotential electron gun, the electron gun electrode group (1) includes a first grid G, as shown in FIG.
~5th grid G are connected and integrated while maintaining a predetermined positional relationship with each other by insulating support rods (3) such as beading glass. When the electron gun electrode group (1) has a unipotential electron gun configuration, the third grid G and the fifth grid G are metal leads (
9) are electrically connected to each other and to which an anode voltage is applied, and at the end of the fifth grid Gs there is a spring conductor which electrically contacts the internal conductive film of the completed cathode ray tube and supplies power to the anode. (8) is welded.

On the other hand, a low focus voltage is applied to the fourth grid G, and a unipotential main electron lens is formed in the third to fifth grids G3 to G5. A lead (10) connected to the neck stem of the cathode ray tube is led out, and similar leads are led out in the first and second grids, respectively. In the figure, the second grid G2
Only the lead (11) for is shown.

On the other hand, a container (4) made of, for example, cylindrical lead glass is prepared. As shown in the perspective view of FIG. 2, this container (4) has a current-carrying terminal (5
) is arranged, and the leet 6) from this is guided out of the container (4). For example, the container (4) is made of cylindrical glass, and the current-carrying terminal (5) made of a metal ring to which one end of the lead (6) is welded is inserted into the open end of the bottom of the container (4), and the open end of the container (4) is made of glass. The end plate (7) can be fritted so that the lead (6) can be led out from the end.

Then, an insulating liquid (2) is contained in this container (4).

Examples of the insulating liquid [2] include fluorocarbon liquid (e.g., fluorinated inert liquid Fluoriner manufactured by Sumitomo 3M Co., Ltd.) F=75 (hereinafter referred to as liquid I), silicone oil such as F-9610CS (hereinafter referred to as liquid I) manufactured by Kaetsu Chemical Co., Ltd. Alternatively, mineral oil such as high-pressure insulating oil A manufactured by Nippon Oil Co., Ltd., JIS, C2320 (hereinafter referred to as liquid ■) may be used.

The insulating liquid (2) contained in this container (4)
The electron gun electrode group (1) is inserted and immersed therein. In this case, the spring conductor (8) provided in the fifth grid Gs of the electron gun electrode group (1) is inserted so as to be in electrical contact with the current-carrying terminal (5).

On the other hand, external lead wires (1
3) are connected by conductive clips (14), respectively. In this state, a knocking process is performed by applying a positive high voltage or a ground voltage to the lead (6) and a predetermined ground or negative high voltage to the external lead wire (13).

The high voltage in this case is selected to be 50 KV, for example.

Cathode ray tube drive tlJ finally obtained at 50KV or less
This is carried out using a DC/AC pulsed high voltage of 1.5 to 3 times the anode voltage.

In addition, when using the above-mentioned liquid I as the above-mentioned insulating liquid,
This has a low viscosity and a relatively low boiling point of 102°C, so after the spot knocking treatment, it is heated and dried at a temperature above the boiling point, for example 110°C, to prevent the insulating liquid (2) from adhering. can be excluded. In addition, when using liquid ■ or liquid ■,
After knocking treatment, wash with a solvent such as trichlorethylene, and then thoroughly wash with detergent, pure water, etc.
After that, a drying process is performed.

In addition, the dielectric strength of each of the liquids 11, liquid (1) and liquid (2), is 40 KV at a gap interval of 2.54 mm for liquid I.

35KV with 2.5mm gap spacing for liquid ■
, 30KV with 2.5mm gap spacing for liquid ■
That's all.

In addition, spot knocking of the electron gun electrode group (1) in the insulating liquid (2) is caused by the interval between high and low pressures, and in the example shown, the interval between the fourth grid G4 and the third and fifth grids G3 and G3. Or it depends on the surface condition of the electrode,
Although it differs depending on the type of liquid used, when the distance between high and low voltage electrodes is 2 mm, the discharge starting voltage is 7 for liquid ■.
KV, 10 KV for Liquids I and ■.

Although the above example shows the case where the electron gun has a unipotential type configuration, it can also be applied to an electron gun electrode group having various electron gun configurations such as a pi-potential type, a tri-potential type, or a bi-unipotential type. You can also do that.

Further, the apparatus for carrying out the knocking treatment step in the method of the present invention is not limited to the example shown in FIG. 1, but as shown in FIG. It is also possible to arrange a shaped electrode (15) around the electron gun electrode group (1) and apply a high voltage between this and the external lead wire (13) to perform the knocking process. In FIG. 3, parts corresponding to those in FIG. 1 are denoted by the same reference numerals, and redundant explanation will be omitted.

〔Effect of the invention〕

In the spot knocking in the insulating liquid (2) according to the present invention described above, the electrode surface condition is improved and the cathode, heater, lead stem, getter container, etc. are attached to the electrode group after this knocking treatment. After that, the cathode ray tube is assembled into a cathode ray tube body and subjected to exhaust treatment, getter spit treatment, sealing treatment, etc. to obtain a cathode ray tube. By avoiding the adhesion and insertion of dust when assembling the gun or installing it into the cathode ray tube body, the electron gun can be made to withstand high voltage.

In the cathode ray tube obtained by the method of the present invention, a decrease in the discharge rate was observed. That is, by making the electrode surface smooth, stray electron emission from the electrode surface was avoided, and as a result, glow discharge and even lightning strikes could be effectively prevented in advance.

In addition, according to the method of the present invention, since the knocking treatment is performed in liquid, it is possible to check and eliminate items that discharge at low voltage in advance, so it is possible to eliminate defective products before the cathode ray tube is completed. Compared to the conventional method of evaluating completed cathode ray tubes to determine the occurrence of defective products, workability can be improved and costs can be reduced.

[Brief explanation of the drawing]

1 and 3 are explanatory diagrams of an apparatus for implementing the method of the present invention, and FIG. 2 is a perspective view of an example of an insulating liquid container. (1) is an electron gun electrode group, (2) is an insulating liquid, (4) is a container, and G1 to G are first to fifth grids. Procedural amendment January 14, 1988 Director General of the Patent Office Kunio Ogawa 1988 Patent Application No. 274038 2 Title of invention Method for manufacturing cathode ray tubes 3 Relationship with the person making the amendment Patent applicant Address: 6-7-35, Kitashina-yo, Tokyo Parts-yo Ward Name (2
18) Sony Corporation Representative Director Norio Ohga 4, Agent Address: 1-8-1 Nishi-Shinjuku, Shinjuku-ku, Tokyo 03-
343-5821@15 (Shinjuku Building) (1) Page 4 of the statement! Lines 4 to 15 change “(Guroshinden)” to “(
(Glow discharge)" is corrected. (2) In the specification, the expression ``It will not be too much...'' in the 4th true line 20 to the 5th true line 1 means that [the inside of the cathode ray tube tube, which should be clean, is instead contaminated] Therefore, it could lead to field emission ('tetraton radiation).'' (3) Same, page 5, line 11, “insulating liquid” is corrected to “insulating liquid”. (4) Same, 61X, lines 11-12, ``M dust or electrode'' is corrected to ``foreign object or protrusion of electrode.'' (5) Same, 7th page, line 1, correct "J for after sealing only after 1 seal." (6) Same, 9th true line 11 r F-96J to rKl'-9
Correct 6J and 61゛. (7) Same page, line 15, F “Insulating liquid” is corrected to “Insulating liquid”. (8) Same, 1st O, lines 5-8 “In this case...
・Do it Nyote. ” is corrected as follows. [Unlike knocking in a vacuum, the applied high voltage in this case is influenced by the volume resistance of the insulating liquid. That is, there are differences in the discharge starting voltage and continuous discharge voltage depending on the volume resistance and the surface condition of the electrode group. Therefore, in the case of a liquid with a high volume resistance (liquid H), a voltage as high as knocking in a vacuum cannot be applied, but approximately 50 KV can be applied with an inter-electrode spacing of 2 ms. In this case, a direct current, an alternating current, or a pulsed commercial voltage is used. Regardless of the voltage, foreign matter or protrusions on the electrodes are removed by discharge in an insulating liquid. Reference value Volume resistance (Ω・1) Liquid 1 8xlO” (25℃) #u1×101
4 or more #m 5X101J or more (80℃)” (9)
Same, page 12, lines 1-2, 1' IJ-do clear (13)
"with" should be corrected to "with the lead wire (13) or the outer peripheral surface of the electrode, etc." (10) Same! 813 pages, 12 lines, 1. Next to ``1'', phosphor powder was placed near the electron gun after exhaust. Dust such as carbon powder, foreign matter, etc. may be present. In this case, it is sufficient to blow away dust, foreign matter, etc. using low-voltage spot nonking to create an electrostatically stable state, and there is no need for a high voltage that would cause melting or sputtering of the electrode constituent atoms as in the case of conventional cathode rays. When the tube is operated, sources such as field emission (electron radiation) and stray emission (glow discharge) can be reliably avoided even when the anode voltage is particularly high. ” to join. that's all

Claims (1)

[Claims] The electron gun electrode group of the cathode ray tube is immersed in an insulating liquid, and in this state, a predetermined high voltage is applied to the required electrodes of the electron gun electrode group to perform knocking treatment, and then the cathode is applied to the electron gun electrode group. , a method for manufacturing a cathode ray tube, which includes the steps of assembling a heater getter, lead stem, etc.