JPS646940Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to an apparatus for applying a conductive material such as graphite to a predetermined position on the inner surface of a cathode ray tube bulb.

2. Description of the Related Art A cathode ray tube bulb is composed of a neck portion 1, a funnel portion 2, and a face portion 3, as shown in FIG. 6, for example. A conductive material such as graphite is coated on the bulb 4, on which the fluorescent film P is previously formed on the inner surface of the face portion 3, over the funnel portion side end of the inner surface of the neck portion 1 and the neck portion side end of the inner surface of the funnel portion 2. A conductive film 5 is formed. The application of this internal conductive film 5 is difficult to automate because the funnel portion 2 is approximately conical, and even more difficult to automate in the case of small valves 4 such as viewfinder type valves because the neck portion 1 is thin. This was done by hand using a brush.

For example, as shown in FIG. 7, a brush 7 is attached to the tip of an elastic long curved handle 6 such as piano wire.
A brush body 8 is prepared, the brush 7 is impregnated with a liquid conductive material made of a mixture of graphite and water glass, and the brush body 8 is placed inside the bulb 4 held in place.
Manually insert the brush 7 into the specified position with the brush 7 first so as not to touch the excess part of the inner surface of the valve, and press the brush 7 to the specified position on the inner surface of the funnel part 2 using the elasticity of the handle 6. In this state, the brush body 8 and the valve 4 are rotated relative to each other around the central axis of the valve, and the brush body 8 is relatively moved in the direction of the central axis of the valve 4, thereby moving the brush 7 from the inner surface of the funnel part 2 to the neck part. The conductive material was applied by moving the brush body 8 relatively to the inner surface of the bulb 1, and then the brush body 8 was pulled out from inside the bulb 4 in such a manner that the brush 7 did not touch any unnecessary part of the inner surface of the bulb.

Further, as shown in FIG. 8, a rigid straight pipe 9 is placed over the handle 6' of a brush body 8' similar to the above, and only the brush 7' protrudes from the tip of the pipe 9, as shown by the chain line in FIG. As shown in the figure, after inserting the handle 6' into the valve 4 to a fixed position, the handle 6' is pushed out from the pipe 9, and the curved tip of the handle 6' brings the brush 7' into elastic contact with the inner surface of the funnel part 2 to move the brush 7' relatively. A conductive material was coated on the inner surface of the valve 4. In the case of FIG. 8, after coating is completed, the brush 7' is separated from the inner surface of the valve 4, the handle 6 is pulled back so that the brush 7' comes close to the tip of the pipe 9, and the brush body 6' is removed together with the pipe 9. Pull it out from inside valve 4.

Problems to be Solved by the Invention By the way, in the case of FIG. 7 above, the long curved handle 6 is inserted and removed into the valve 4 so that the brush 7 does not come into contact with the unnecessary part of the inner surface of the valve.
A considerable degree of skill was required of the operator, and workability was extremely poor. On the other hand, in the case of Fig. 8, the brush body 8'
Put the handle 6' into the straight pipe 9 and use the pipe 9 as a guide to move the brush 7' in and out.
The brush 7' is less likely to come into contact with unnecessary parts of the inner surface of the valve, resulting in relatively good workability. However, in the case of FIG. 8, the contact pressure of the brush 7' against the inner surface of the bulb when applying the conductive material is due to the contact pressure of the brush 7' of the handle 6'.
Since it is determined only by the spring force of the short portion between the pipe 9 and the pipe 9, it is difficult to obtain sufficient contact pressure, and coating spots are likely to occur.

Means for solving the problems This invention was proposed in view of the above problems.
The brush body has a handle made of a shape memory alloy that is linear in a low temperature state and bends and deforms in a high temperature state, and a means for heating the handle of the brush body, and the linear brush body is inserted into a bulb and the heating means The above-mentioned problem is solved by a device in which the handle of the brush body is bent so that the brush contacts the inner surface of the bulb to apply the internal conductive material.

Function: By forming the brush handle with a shape memory alloy as in the above method, the shape of the handle at low temperature (room temperature) is such that even if the brush sways slightly, it does not come into contact with the valve. It becomes easier to take things in and out, improving work efficiency. Further, by setting the brush bent in a high temperature state to contact the inner surface of the valve with sufficient pressure, good conductive material application can be performed at all times.

Embodiment An embodiment of the present invention for the relatively small valve 4 shown in FIG. 6, for example, will be described below with reference to FIGS. 1 to 4.

In Figure 1, 10 is a single strip-shaped support.
It is made of rigid body. Reference numeral 11 denotes a handle made of a shape memory alloy in the shape of a strip whose rear end is caulked to one side of the tip of the support column 10 and fixed by welding or the like.It extends straight in the same direction as the support column 10 at room temperature, and when heated above a certain temperature. The memorized shape when heated, for example, from the fixed rear end to the pillar 1
Curving deforms in the opposite direction to 0. 12 is a brush fixed to the entire surface of the deformable tip of the handle 12.
Reference numeral 13 designates a brush body that is an integral part of the support 10, handle 11, and brush 12, and 14 designates a cylindrical body that houses the brush body 13, and has an outer diameter slightly smaller than the inner diameter of the neck portion 1 of the valve 4. It is inserted into the network part 1 as appropriate.

Next, operation examples according to the above embodiment will be sequentially explained.

At room temperature when the handle 11 is straight, the brush 12 is impregnated with a liquid conductive material containing a mixture of graphite and water glass, and the brush body 13 has the brush 12 inside the cylindrical body 14.
is housed with a gap so that it does not touch the inner surface of the cylindrical body 14, and this state is maintained between the cylindrical body 14 and the brush body 1.
3 are inserted into the valve 4 into position as shown in FIG. Alternatively, the cylindrical body 14 may be inserted into the valve 4 first, and the brush body 13 may be inserted into this cylindrical body 14. In any case, when inserting the brush 12 into the neck part 1 of the valve 4, the cylindrical body 14 is present between the brush 12 and the inner surface of the neck part 1, and the brush 12 is inserted through the central axis of the neck part 1. Since the brush 12 is inserted, there is no fear that the brush 12 will directly touch the inner surface of the neck portion 1 and the conductive material will adhere to the excess portion of the inner surface of the neck portion 1, and the brush can be inserted with good work efficiency.

When this brush insertion is completed, the application member 13 is pushed up from the cylindrical body 14 and the handle 1 is moved as shown in FIG.
1 is made to protrude from the cylindrical body 14. After that, as shown in FIG. 4, hot air heated to a predetermined temperature by a heating means (not shown) is blown into the cylinder 14 from the opening at the lower end, and at the same time, it is exhausted from the opening at the neck part 1 of the valve 4. . Then, when the handle 11 is heated by the hot air blown up from inside the cylinder 14 and reaches a predetermined temperature, it curves and tilts forward, so that the brush 12 comes into elastic contact with a part of the inner surface of the funnel part 2. The contact pressure at this time is determined by the deformation rate of the handle 11, so the brush 1 can be moved with a sufficiently good and stable contact pressure.
2 corresponds to the inner surface of the funnel portion 2. While maintaining this state, the bulb 4 and the brush body 13 are rotated and moved relative to each other in the axial direction to coat the inner surface of the bulb 4 with a conductive material.

When the application of the conductive material is completed, cold air is blown into the cylinder 14 instead of hot air to cool the handle 11. Then, the handle 11 returns to its original straight state and the brush 1
2 is separated from the inner surface of the valve 4. After that, apply member 13
is removed from the valve 4 together with the cylinder 14, or the application member 13 is removed first and the cylinder 14 is removed last.
In this case as well, the brush 12 does not touch the inner surface of the neck portion 1, and the work can be performed with good efficiency.

Next, another embodiment of the present invention will be described based on FIG.

The difference between the embodiment shown in Fig. 5 and the above embodiment is that the handle 1
The only difference is that a heating element (heating means) 15 such as a ceramic heater that generates heat when energized is integrally fixed to a part of the heating element 1. In this embodiment, the cylindrical body 14 and the brush body 13 are inserted into the valve 4, the tip of the handle 11 is made to protrude from the cylindrical body 14, and then the heating element 15 is energized to generate heat to a constant temperature. As a result, the handle 11 is deformed and the conductive material is applied, and after the application, the electricity to the heating element 15 is stopped and the handle 11 is returned to its original straight state. This method eliminates the need for hot air, which is advantageous in terms of equipment.

Although natural cooling is possible for cooling the handle 11 after heating in the embodiment shown in FIG. 5, the working time can be shortened by forced cooling by blowing cold air. Wind may be blown onto the heating element 14 by making a hole and sucking air through the cylinder 14, thereby preventing excess wind from hitting the fluorescent film P. Further, as a forced cooling means, it is also possible to fix an electronic refrigeration element that cools by electricity to the handle 11 together with the heating element 15 to perform forced cooling.

Note that the present invention is not limited to the above embodiments, and it is also possible to use a combination of a plurality of shape memory alloy handles depending on the size of the valve. Further, the cylindrical body in the above embodiment is not necessarily required if the valve neck diameter is large.

Effects of the invention According to the invention, if the deformable shape of the shape memory alloy handle is determined according to the size of the valve, the brush body can be moved in and out of the valve without worrying about adhering the conductive material to the unnecessary part of the inner surface of the valve. It can be easily done, improving work efficiency and automation. Further, since the contact pressure of the brush body against the inner surface of the bulb is determined by the deformation rate of the handle, it is possible to stabilize this contact pressure, and to perform conductive material application with good reliability.

[Brief explanation of the drawing]

Fig. 1 is a partial side sectional view showing one embodiment of the present invention, Figs. 2 to 4 are side sectional views showing various states of use of the device shown in Fig. 1, and Fig. 5 is another embodiment of the present invention. It is a side sectional view showing an example. FIG. 6 is a side sectional view of the bulb, and FIGS. 7 and 8 are side sectional views of the bulb for explaining two examples of conventional internal conductive film coating apparatuses. 4... Valve, 5... Internal conductive film, 11... Shape memory alloy handle, 12... Brush, 13... Brush body, 15
...Heating means.

Claims (1)

[Scope of utility model registration request] The brush body has a handle made of a shape memory alloy that is linear in a low temperature state and bends and deforms in a high temperature state, and a means for heating the handle of the brush body, and the linear brush body is inserted into a bulb and the heating means A device for applying an interior conductive film for a cathode ray tube, characterized in that the handle of the brush body is bent to bring the brush into contact with the inner surface of the bulb to apply the interior conductive material.