JPS5981842A - Explosion-proof type cathode-ray tube and manufacturing method thereof - Google Patents

Abstract

PURPOSE:To improve a degree of adhesion as well as to give good film strength, rust preventing effectiveness and conductivity to a cathode-ray tube, by heating each of explosion-proof component parts coated with heat-resistant conductive paint inclusive of an inorganic substance on their surface, and baking the heat-resistant conductive paint. CONSTITUTION:The whole body of an oblong, ringlike band 5 fitted with a lug 6 is coated with heat-resistant conductive paint containing an inorganic substance and conductive matter as a solid portion, and its chemical make-up consists of silicon 10- 15wt%, potassium about 10wt%, calcium about 5wt%, carbon 10-15wt% and others by way of example. The thickness of film coating is about 17mum and its color is black. After applying and drying up them, they are heated at about 400 deg.C with a gas burner and the band is expanded in structure. With this heating process, the adhesive strength of a coating film intensifies. Then, the expanded band is fitly installed in a panel side wall protective tape 8 part, and this panel side wall is constricted tight. When an ohmic value of this coating film is at 17mum in thickness, it is able to obtain that of 20- 40OMEGA/cm or so, and when this film thickness is made to be larger, rust preventing effect is sufficiently secured yet higher.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical details of the invention] The present invention relates to a defensive cathode ray tube and a method for manufacturing the same.

[Technical background of the invention and its moving points]

The Braun 1 envelope, as shown in Figure 1, has a substantially rectangular panel (1), a funnel-shaped funnel (3) and a neck (
4). When the inside of such an envelope is evacuated, stress as shown by the arrow is exerted due to the pressure difference between the inside and outside, and as a result, the envelope receives stress in the direction of deformation shown by the dotted line, causing slight damage to the southern part of the envelope from the outside and the outer envelope. It is easily destroyed using minute defects in the body as the origin. This effect is particularly noticeable at the corners of the panel. Therefore, as an explosion-proof structure to prevent such destruction, the side wall (2) of the panel (1)
) with a metal band (not shown) is effective.
Most commonly used. In the 11/j Qt structure, in which the panel side walls are tightened with metal bands, a long metal band is often mechanically tightened by welding and fixing both ends. There are variations in the force when tightening from tube to tube, and the pressure during tightening is not evenly distributed.

Instead of the above-mentioned mechanical tightening method, a so-called baking method is also used. As shown in Fig. 2, this firing method involves forming a metal band (5) such as a tension band into a rectangular annular shape in advance, and a tube mounting terminal (6) (hereinafter referred to as a lug) having a receiving hole in one corner. Welded fixation [7] is provided.

On the other hand, a protective tape (8) such as adhesive tape is attached to a portion of the panel side wall (2) of the cathode ray tube that is to be tightened. Next, the tension band (5) is heated with a burner (9) or with electricity. Inflate. In this state, the tension band (5) is fitted onto the protective tape (8) of the pile side wall (2) of the cathode ray tube. FIG. 3 shows this state. Part 1. The tension band contracts as it cools and tightens the panel side wall. The firing method is to form the tension band into a rectangular ring shape, and the total inner circumference length must be selected appropriately for each total outer circumference length of the panel loft to which it is applied. It has an unbiased advantage.

Here, the heating temperature of the tension pan F is kept as low as possible in order to reduce heat shock to the cathode ray tube, but it is determined by the ease of inserting the tube during firing, and is generally 400°C to 900°C. This is because the tension bands used are typically made of mild steel, stainless steel, aluminum, etc., and are limited by their cost and mechanical strength.

In addition, appropriate selection of the external color of the tension band and measures to prevent rust are required. For example, soft 6t'
As shown in Fig. 4, the tension band whose cumulative month is 1 is generally coated with a tightening layer (11) mainly made of zinc or nickel on the surface of the band body (11). When baking method 1' is applied to such a band, there is a problem that the plating layer burns or peels off due to high temperature heating of the band, and the anti-glaze effect is lost.For this reason, if the thickness t of the plating layer is increased, it may peel off during shaping. It also becomes easy to peel off due to the difference in expansion coefficient between the tension band and the metal.It is also possible to bake the tension band and apply a rust preventive agent after tightening, but such post-coating is not recommended. First of all, it is extremely difficult to apply it to all the tension bands and lugs without any gaps, and if you accidentally apply it to the side wall of the panel, it is necessary to remove this J'L. be.

For some reason, protection 4☆ is usually required to prevent light reflection from explosion-proof parts such as bands and lugs when viewed from the panel 011 side, and to prevent uneven burning during firing from looking unsightly. This is because uneven application actually impairs the appearance. Second, second-class explosion-proof parts require a certain degree of isoelectricity in order to be grounded and to attach degaussing coils, etc., but the above-mentioned anti-M paints generally have high insulating properties, so ! This is because Il becomes difficult.

[Purpose of the invention]

The present invention has been made in view of the above points, and it is an object of the present invention to provide an explosion-proof cathode ray tube that has sufficiently high coating strength by firing method, has a high bonding one-piece effect, has high sturdiness, and is easy to manufacture, and a method for manufacturing the same. With the goal.

[Summary of the invention]

The present invention applies to the surface of explosion-proof parts including metal strips. na+14
:> Its properties are to provide strength, anti-caking effect, and conductivity.

[Embodiments of the invention]

Examples of the present invention will be described in detail below.

The basic structure of the smoke-proof cathode ray tube of the present invention is the same as that shown in FIG. 3, so detailed explanation will be omitted.

First, a metal band, ie, a tension band, is prepared using a long piece of flexible material. This band has a thickness of approximately 0
．． 8 questions, the width is 15m to 40 fin II. For example, when applying to a 10-inch cathode ray tube, it is 15B to 20 fin, and when applying to a 20-inch cathode ray tube, it is (15 m to 40 tl). is used, and is appropriately selected from the viewpoint of band strength depending on the tightening force of the cathode ray tube to be applied, which will be described later.

Such a tension band is formed so as to correspond to the substantially rectangular panel side wall of the type of pipe to which it is applied, and both ends are firmly fixed by welding to form a substantially rectangular ring shape. At this time, the total inner circumference of the band is formed to be slightly shorter than the corresponding total outer circumference of the cathode ray tube panel to which it is applied. For example, when applied to a 20-inch cathode ray tube, the corresponding total outer circumference of the panel is approximately 1540 fins, and the total inner circumference of the rectangular annular band is 3 to 4 fins shorter than the above-mentioned panel outer circumference. It is good to form it like this. On the other hand, adhesive tape, which is slightly wider than the band, is attached to the side wall of the cathode ray tube panel as a protective tape. That is, the tightening force after burning out, which will be described later, will vary depending on the difference between the band inner circumference length and the panel outer circumference length. For example, the flatter the curved surface of the front panel is, the stronger the deformation force shown by the dotted line in Figure 1 will be, so it must be tightened more strongly.In this case, the difference between the inner circumference of the band and the outer circumference of the panel must be larger. No. Therefore, the dimensions of the band and the dimensions of the rectangular or sentinel should be selected depending on the type of pipe to which it is applied.

Next, lugs are welded and fixed to each corner of the band formed into a rectangular ring shape (see Figure 4).
. This lug is one of the explosion-proof parts necessary for attaching the cathode ray tube to the receiver frame, grounding the band, and attaching the extinction coil after explosion-proofing is completed. To install the lugs, heat-resistant 4-electrode paint is applied to the entire rectangular ring band. The coating method may be an erosion method, but a spray method is suitable in terms of economy and uniform film thickness. This heat-resistant conductive material contains a solid substance and a conductive substance, and its composition is silicon 1Qwt% to 15w1%, potassium about IQwt%, calcium about 5wt%, carbon 10w.
t% to 15wt%, and trace amounts of iron, zinc, manganese, etc., and coloring components such as titanium, copper, chromium,
Contains nickel, cobalt, etc. In addition, in order to uniformly disperse the solid component and adjust the viscosity, a liquid component is added to 1. A thinner-based organic material is then added. Coating film thickness is approximately 17μ
The coating color is black. After coating and drying the above heat-resistant electrically conductive film, the band is heated and expanded by heating it to about 400° C. with a gas burner.

This heating increases the adhesion strength of the coating film due to the burning effect. Next, the expanded pan F is fitted onto the panel side wall, and the panel side wall is tightened by contraction during cooling. Since the shrinkage occurs evenly during cooling, it is possible to prevent uneven forces from acting on the tightening force as in mechanical seaming. still,
Baking of the coating film is done at 200°C to 250°C, where the coating film softens and then hardens, so depending on the handling, the coating film can be easily damaged, and when the liquid component evaporates, it generates a lot of gas, so it is different. The heating temperature in the chamber may be 300° C. or lower from the economical point of view of the burning treatment furnace. what,
Even in the case of 1 t, the appearance color after baking was not much different from that at the time of application. The appearance color can be freely selected from the most common gray to black by appropriately selecting coloring components, but other appearance colors such as yellow can also be obtained.

In addition, the 1riiJ thermally conductive film may be applied to the lug and band separately before the lug is attached, but in this case, there is a risk that the welding strength of the lug to the band may not be ensured, so it is only for welding. 1. Peel off the film or use a protective film to prevent it from attaching. It is preferable to keep it.

Similarly, coating and burning may be performed on the band-shaped annular molding 01, but in this case as well, it is preferable to perform the same process as above. Resistance value is 11.!, 2゜07c at 17μm
1 u of about 40 Ω/cnt was obtained, and it was used for grounding and 1. It is sufficient for all electrical interviews and contacts. This resistance value can be selected by changing the carbon content, but if it is too large, the film strength will decrease, and if it is too small, the resistance value will be too large. As long as it is used in
is suitable. By the way, in the case of a chromium-based blackened film produced by heating nichrome plating, its resistance 4M is about the same as that of zinc plating, which is about 2 Ω/cm to 4 Ω, while for ordinary heat-acclimated paint, the resistance is 1 Ω/cm to 10 MΩ/c 1rL. has value.

Next, the selection of the film thickness will be explained regarding the film strength and antirust effect of coating 1+W. It is generally said that the strength of the coating film is dependent on its thickness, but when it comes to explosion-proof parts, 1.
It is clear that the rust prevention effect decreases if Furthermore, if the thickness is increased, the rust prevention effect can be sufficiently maintained, but peeling and cracking are likely to occur during heating or due to external force.

Fig. 5 is a 4'<f diagram showing the correlation between the two, with the horizontal axis representing 11j:Σ thickness and the vertical axis representing red 6'1"1 occurrence f', 1 degree, and film strength. Occurrence is J l 8 Z 23
In accordance with 711A rating, the extent of red rust on Ruitsu J parts was observed after spraying 5% salt water at 35°C for 48 hours17
When heated to 700°C, the film strength was as strong as that in the winter peeling state. Furthermore, the symbol 0 on the vertical axis
1, (], △, ×, XX indicate the conditions in the table below, respectively.1.
ing.

The minimum film thickness that can be selected from the observation results of the degree of red rust (a) in Figure 4 is X s p m or more, and the film strength (bl (7
) The maximum film thickness that can be selected from the results is within 30 μm.

iQ is 11% in VJ range from 5 p m to 30 μm
If J or more is selected, it can be used for both l'J illusion and strength, but if economical considerations are taken into account, 10 μm)') to 20 μm is preferable.

[Effect of light]

As described above, according to the present invention, a firing type explosion-proof type brown belt has sufficient rust prevention effect, film strength, and toughness.
2 Adjust its appearance color 1. It is possible to obtain an explosion-proof type brown frost that is easy to manufacture, and its industrial value is great.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram to explain the deformation stress applied to the cathode ray tube, Figure 'i442 is a schematic diagram to explain the explosion-proofing process of the firing method, and Figure 3 is a schematic diagram showing the cathode ray tube after tensile and yonbanod fittings. The cross-sectional view, Figure $4, is a schematic diagram showing an enlarged main part of Figure 3, and 94'<51XI is a characteristic diagram showing the correlation between film thickness, degree of red rust, and film strength. (1)... Panel (2)... Side wall (3
)...Hwang Yi Lu (4)...Lee Tuk (
1j)...Metal phase (6)...Lug (force...Mounting hole (8)...Protective tape (9)
)... Barna's agent Patent attorney Noriyuki Chika (one idiot)

Claims (1)

[Scope of Claims] 1) The panel side wall of a cathode ray tube having a substantially rectangular panel is surrounded by an explosion-proof part including a metal band,
In an explosion-proof cathode ray tube in which the side wall of the panel is tightened by the contraction force after heating and expansion of the band, the surface of the explosion-proof component including the metal band is coated with a 111;.1 thermally conductive film containing an inorganic substance. 2) The explosion-proof cathode ray tube according to claim 1, wherein the heat-resistant conductive film contains 19 wt% to 15 wt% of carbon. 3) The explosion-proof cathode ray tube according to claim 1, wherein the heat-resistant conductive film is gray to black. 4) The explosion-proof cathode ray tube according to claim 2, wherein the heat-resistant conductive film has a thickness of 5 μm to 30 μm. 5) An explosion-proof fitting device that is a V-proof component that includes a heated and expanded metal band on the side wall of the panel of a cathode ray tube having a substantially rectangular pile, and is tightened to the side wall of the panel by the contraction force of the metal band when it is cooled. In the method of manufacturing a cathode ray tube,
a step of coating the front m1 of the explosion-proof part including the metal strip with a cocoon heat-conducting Tb paint containing an inorganic substance; a step of heating the epidemic prevention part coated with the heat-resistant #electroconductive paint; and a step of heating the heated explosion-proof part. The method is characterized by comprising a step of fitting the component onto the side wall of the panel, and a step of tightening the component to the side wall of the panel by the contraction force of the heated and expanded metal band upon cooling.
A method for manufacturing an i-explosion cathode ray tube. 6) The temperature at which the metal band described in iiJ is heated and expanded is set to 400.
Claim 5, characterized in that it is not less than ℃4-.
2. Method for manufacturing explosion-proof cathode ray tubes described in Section 1. 7) The step of heating the metal strip at 200°C to 300°C
Preheating step of 400℃ and 114' of gold on top:
Special fl characterized by H heating 11 consisting of grudge process
' The method for manufacturing an explosion-proof cathode ray tube according to item 5.