JPH1186729A - Manufacture of cathode-ray tube and apparatus thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing a apparatus of a cathode-ray tube, in which lowering of the vacuum level due to sealing failure or spark or mask clogging failure due to a peeled foreign material of a conductive coating is reduced. SOLUTION: This manufacturing method of cathode-ray tube comprises a coat-applying process for injecting and applying a conductive coating 14a to the full area of the inner face of a funnel 12 and a coat removing process for removing the conductive coating 14a applied to a neck part 11 of the funnel 12, the coat removing process having washing means 22 for spraying cleaning water 21 on the inner circumference face of the neck part 11 and a removal means 27 for mechanically removing the conductive coating 14a applied to the neck part 11, from the end face of the neck part 11 up to within a given range L.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a cathode ray tube used for a television receiver, a computer display, and the like.

[0002]

2. Description of the Related Art As shown in FIG. 5, a conventional method of manufacturing a cathode ray tube uses a funnel of a cathode ray tube 1 in order to prevent contamination of a neck end and obtain a cathode ray tube having a good sealing shape. A paint application step of injecting and applying the conductive paint 3 to the inner surface of the funnel 2 and a paint collecting tool 5 having a conical upper surface formed on the inner surface 4a of the end portion 4 of the neck portion 4 of the funnel 2 so as to adhere to the inner surface. Excessive conductive paint 3 applied to pipe 5
a, and at the same time that the conductive paint 3 is collected by the paint collecting tool 5, the washing water 6 is caused to flow to the outer peripheral surface 4 b of the end of the neck 4, and the outer peripheral surface 4 b of the end of the neck 4
And a cleaning step of cleaning the conductive paint 3 that has oozed out of the substrate (Japanese Patent Laid-Open No. 7-85787).

[0003]

However, in such a method for manufacturing a cathode ray tube, as shown in FIG. 6, the outer peripheral surface of the neck portion 4 is cleaned by a cleaning step. When the conductive paint 3 is applied to a large number of cathode ray tubes 1 having a flareless neck 4, the conductive paint 3 from the paint application step is hardly cleaned. A large amount adheres to the conical portion of the paint collection tool 5. As a result, in the collecting step, the paint collecting hole 5c of the paint collecting tool 5 is clogged with the conductive paint 3, and the conductive paint 3 is peeled off from the conical portion of the paint collecting tool 5 and adheres to the inner surface of the neck portion 4. Problems and
Subsequently, in the cathode ray tube 1 to be manufactured, the adhesion between the inner surface 4a of the end portion of the neck portion 4 and the conical portion of the paint collection tool 5 is poor,
Due to the problem that a large amount of the conductive paint 3 oozes out from the end portion and the end outer peripheral surface 4b of the neck portion 4 and cannot be completely cleaned in the cleaning step, when the cathode ray tube is assembled, the degree of vacuum is reduced due to poor sealing, and the conductivity is reduced. Sparks between the electrodes and defective clogging of the mask due to the peeling of the paint and foreign matter occurred.

The present invention has been made on the basis of the above circumstances, and a reduction in the degree of vacuum due to poor sealing at the time of assembling a cathode ray tube, and spark or mask clogging between electrodes due to peeling of a conductive paint. An object of the present invention is to provide a method and an apparatus for manufacturing a cathode ray tube with reduced defects.

[0005]

According to the present invention, there is provided a cathode ray tube manufacturing apparatus comprising: a funnel supporting step for installing a funnel inner surface on an upper surface side; and a method for injecting and applying a conductive paint over the entire funnel inner surface. A paint application step, a paint drying step for drying the conductive paint applied to the entire inner surface of the funnel, and a paint removal step for removing the conductive paint applied to the neck of the funnel in a wet state. Washing means for spraying washing water on the inner peripheral surface of the neck portion, and removing means for mechanically removing the conductive paint applied to the neck portion from the end face of the neck portion to a predetermined range. And

With this manufacturing apparatus, before the conductive paint applied to the neck portion is dried, the conductive paint on the inner peripheral surface of the neck portion is washed with washing water, and the conductive paint from the end face of the neck portion to a predetermined range is mechanically removed. Can be removed.

Further, in the cathode ray tube manufacturing apparatus according to the present invention, the paint removing step may prevent the conductive paint in the cone portion of the funnel from dripping onto the inner circumferential surface of the neck portion while the inner circumferential surface of the neck portion is being washed with the washing water. It has means for preventing drooping.

With this manufacturing apparatus, it is possible to prevent the conductive paint in the cone portion of the funnel from dripping on the inner peripheral surface of the neck portion.

[0009]

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

As shown in FIG. 4, a cathode ray tube according to a first embodiment of the present invention comprises a face plate 8 having phosphors 7 of a plurality of colors on an inner surface, and a cone portion adhered behind the face plate 8. 9 and formed behind the cone 9,
The apparatus includes a funnel 12 having a neck portion 11 in which an electron gun 10 for emitting an electron beam is arranged, and a shadow mask 13 arranged to face the phosphor 7 of the face plate 8. Also, the funnel 12
An inner conductive film 14 composed mainly of graphite and titanium oxide applied to the inner surface thereof, an outer conductive film 15 composed mainly of graphite applied to the outer surface thereof, and the inner surface of the electron gun 10 via the inner conductive film 14. And an anode 16 for applying a high voltage to the final electrode.

The cathode ray tube manufacturing apparatus of the present invention applies a conductive paint 14a to the inner surface of the funnel 12 to form the inner conductive film 14, and as shown in FIG. The funnel supporting step A for setting the outer peripheral surface of the funnel 12 with the inner surface of the funnel 12 as the upper surface by the base 17 and the injection nozzle 18 disposed above the support 17 provide a conductive material mainly composed of graphite and titanium oxide. A paint application step B in which the paint 14 a is injected and applied to the entire inner surface of the funnel 12, and hot air 20 is applied to the conductive paint 14 a applied to the entire inner surface of the funnel 12 by an air nozzle 19 disposed above the support 17. And a paint drying step C for drying the conductive paint 14a over the entire inner surface of the cone portion 9 of the funnel 12 in particular. The section 11 is applied conductive coating 14
and a paint removing step D for removing a in a wet state. The paint removing step D includes washing water 2 on the inner peripheral surface of the neck 11.
The cleaning means 22 for spraying 1 and the inner peripheral surface of the neck portion 11 are cleaned with the cleaning water 21 while the hot water nozzle 23 is used to apply 60 to the outer peripheral surface 25 of the boundary between the cone portion 9 and the neck portion 11.
70 ° C. hot water 24 is sprayed to prevent the conductive paint 14 a of the cone portion 9 from dripping onto the inner peripheral surface of the neck portion 11, and the conductive paint 14 a applied to the neck portion 11 Removing means 27 for mechanically removing a predetermined range L from the end face of the neck 11;
A collection means 29 for collecting by a collection tool 28 a washing water 21 sprayed on the inner peripheral surface, a warm water 24 sprayed on the boundary outer peripheral surface 25, and a collected material of the conductive paint 14a mechanically removed by the removing means 27; have. Note that the range from the end face of the neck 11 to the predetermined range L in the removing means 27 means at least the end face of the neck 11 and the neck 11.
It points to a predetermined range L on the inner surface.

As shown in FIG. 2 and FIG.
Reference numeral 2 denotes a cylindrical body 31 having a plurality of holes 30 for spraying the washing water 21 on the outer peripheral surface and having a cross-shaped cross section. One end of the cylindrical body 31 is inserted into the neck part 11 from the end of the neck part 11. The other end of the tubular body 31 is fixed to a holder 32 provided to face the end face of the neck portion 11. Holder 32
A cylindrical shaft 33 that supplies the washing water 21 to the plurality of holes 30 of the cylindrical body 31 and rotates (120 to 200 RPM) about the tube axis Y and moves up and down in the tube axis Y direction;
And a blade fixing base 34 fixed to the outer peripheral surface of the blade. The removal means 27 has a blade fixing base 34 at one end.
A first blade 36 made of an elastic material such as neoprene rubber or silicon rubber, the other end of which is slidably contacted with the end surface of the neck portion 11, and a first end thereof having a cylindrical shape. A plate made of an elastic material such as neoprene rubber or silicon rubber, which is fixed to the body 31 by being sandwiched by a second guide plate 37 and whose other end is in sliding contact with the inner surface of the neck portion 11 from the end surface of the neck portion 11 to a predetermined range L. A second blade 38 of
One end side is fixed to the blade fixing base 34, and the other end side is configured by a block-shaped third blade 39 made of an elastic body such as urethane sponge and slidably contacting the outer peripheral surface of the end of the neck portion 11. As shown in FIG. 1, the collecting tool 28 of the collecting means 29 surrounds the end of the neck portion 11, the holding tool 32, and the like, and collects the wash water 21, the warm water 24, and the collected material of the conductive paint 14 a. 40, and a discharge pipe 41 for discharging the collected material in the collection container 40.

The first blade 36 and the second blade 38 have a thickness of 0.5 mm to 1.5 mm and a contact surface W with the neck 11 of 5 mm to 10 mm. The tubular body 31 has a cross shape in order to improve the cleaning efficiency of the neck 11 and the removing unit 27. The plurality of holes 30 of the tubular body 31 are formed so that the washing water 21 is directed downward by 15 to 30 ° with respect to the horizontal line in order to remove the conductive paint 14 a from the end of the neck portion 11 to a predetermined range L. Make up.

Next, the operation and effect of the embodiment of the present invention will be described. In the first embodiment of the present invention, in the paint removing step D, the cleaning means 22 for spraying the washing water 21 on the inner peripheral surface of the neck 11 and the conductive paint 14a applied to the neck 11 The removal means 27 for mechanically removing the conductive paint 14a applied to the neck portion 11 from the end face of the neck portion 11 to a predetermined range L allows the conductive paint 14a applied to the neck portion 11 to be dried before the conductive paint 14a applied to the inner peripheral surface of the neck portion 11 is dried. The unnecessary conductive paint 14a of the neck portion 11 can be mechanically and reliably removed while the washing water 21 is being washed with the washing water 21, and the removing means 27 can also be washed with the washing water 21. As a result, even when a large number of cathode ray tubes 1 having the flareless neck portion 11 are manufactured, the conductive paint 14a is removed from the end surface of the neck portion 11 to a predetermined range L, so that the sealing when assembling the cathode ray tube is performed. It is possible to reduce sparks between the electrodes and defective mask clogging due to a decrease in the degree of vacuum due to the defect and the peeling of the conductive paint.

In the paint removing step D, while the inner peripheral surface of the neck portion 11 is being washed with the washing water 21, the hot water nozzle 23
Since the drip prevention means 26 for spraying hot water 24 is provided on the outer peripheral surface 25 of the boundary between the cone 9 and the neck 11, the conductive paint 1 on the inner peripheral surface of the cone 9 at the boundary is provided.
4a can be prevented from drying and dripping on the inner peripheral surface of the neck portion 11, and the outer peripheral surface of the neck portion 11 can also be cleaned by the warm water 24.

Further, the first blade 36 made of an elastic material and the second blade 38 made of an elastic material are removed means 27.
And the neck portion 11 is in surface contact, so that even if the attachment accuracy of the first blade 36 and the second blade 38 to the neck portion 11 is rough, the conductive paint 14a in the predetermined range L of the neck portion 11 Can be removed,
In addition, even if the inner diameter of the neck portion 11 changes depending on different types, the conductive paint 14a in the predetermined range L of the neck portion 11 can be similarly removed.

In the above embodiment, the first blade 36 and the second blade 38 are in surface contact with the neck portion 11, but the first blade 36 and the second blade
May be in contact with the end surface of the neck portion 11 and the inner peripheral surface of the neck portion 11, and in this case, the effect of mechanically removing the conductive paint 14a of the neck portion 11 can be further improved. Further, in the above embodiment, the shaft 33 of the holder 32 rotates around the tube axis Y and moves up and down in the tube axis Y direction. It may move up and down in the Y direction. Further, in the paint drying step C of the above-described embodiment, the conductive paint 14a on the entire inner surface of the cone portion 9 is dried by blowing hot air 20, but is not limited thereto, and is dried by a heater and a far-infrared lamp. You may. Further, the dripping preventing means 26 is performed by spraying the hot water 24 on the outer peripheral surface 25 of the boundary portion. However, the present invention is not limited to this, and hot water, a heater, and a far-infrared lamp may be used.

[0018]

As described above, according to the present invention, in the paint removing step, the cleaning means for spraying the washing water on the inner peripheral surface of the neck portion and the conductive paint applied to the neck portion are applied to the end portion of the neck portion. And a removing means for mechanically removing the conductive paint from the end of the neck portion to a predetermined range from the end of the neck portion. It is possible to reduce sparks and mask clogging defects due to a decrease in vacuum degree due to stopping failure and peeling of the conductive paint.

Further, the paint removing step includes a dripping preventing means for preventing the conductive paint on the cone portion of the funnel from dripping on the inner circumferential surface of the neck portion while the inner circumferential surface of the neck portion is washed with the washing water. In addition, it is possible to further reduce sparks and mask clogging defects due to a decrease in the degree of vacuum due to the above sealing failure and peeling of the conductive paint.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a cathode ray tube manufacturing apparatus according to a first embodiment of the present invention.

FIG. 2 is an enlarged plan sectional view of a neck portion of the funnel.

FIG. 3 is a front sectional view of the same.

FIG. 4 is a sectional view showing a cathode ray tube according to the first embodiment of the present invention.

FIG. 5 is a front sectional view showing a conventional cathode ray tube manufacturing apparatus.

FIG. 6 is an enlarged front sectional view of a neck portion of the funnel.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Neck part 12 Funnel 14a Conductive paint 21 Cleaning water 22 Cleaning means 26 Drip prevention means 27 Removal means

Claims (9)

[Claims] A funnel supporting step for placing the inner surface of the funnel on the upper surface side; a paint applying step for injecting and applying a conductive paint over the entire inner surface of the funnel; and a conductive coating applied over the entire inner surface of the funnel. A paint drying step for drying the conductive paint, and a paint removal step for removing the conductive paint applied to the neck portion of the funnel in a wet state, wherein the paint removal step is performed on the inner peripheral surface of the neck portion. A cathode ray tube manufacturing apparatus, comprising: a washing means for spraying washing water on the neck portion; and a removing means for mechanically removing a conductive paint applied to the neck portion from an end surface of the neck portion to a predetermined range. 2. The paint removing step includes a dripping preventing means for preventing the conductive paint on the cone portion of the funnel from dripping on the inner peripheral surface of the neck portion while the inner peripheral surface of the neck portion is being washed with the washing water. 2. The method for manufacturing a cathode ray tube according to claim 1, wherein: 3. The apparatus for manufacturing a cathode ray tube according to claim 2, wherein the dripping preventing means sprays hot water on the outer peripheral surface of the boundary between the cone portion and the neck portion of the funnel. 4. The cleaning means includes a tubular body inserted into the neck from the end of the neck and having a plurality of holes for spraying cleaning water on the inner peripheral surface of the neck. The apparatus for manufacturing a cathode ray tube according to any one of claims 1 to 3. 5. The apparatus for manufacturing a cathode ray tube according to claim 4, wherein the cylindrical body of the cleaning means rotates or rotates about a tube axis. 6. A removing means comprising: a holder provided at an end of a neck portion, which rotates or rotates around a tube axis; one end fixed to the holder, and the other end provided at an end of the neck. The apparatus for manufacturing a cathode ray tube according to any one of claims 1 to 5, further comprising a first blade slidably contacted. 7. The removing means has a second blade having one end fixed to the cylindrical body of the cleaning means and the other end slidably contacting the inner surface of the neck portion. An apparatus for manufacturing a cathode ray tube according to the above. 8. The removing means according to claim 6, wherein the removing means has a third blade having one end fixed to the holder and the other end slidingly contacting the outer peripheral surface of the end of the neck portion. Of cathode ray tube manufacturing equipment. 9. A paint applying step for injecting and applying a conductive paint over the entire inner surface of the funnel, and a paint removing step for removing the conductive paint applied to the neck portion of the funnel in a wet state. Comprising, said paint removing step,
A method for manufacturing a cathode ray tube, comprising: simultaneously spraying washing water on an inner peripheral surface of the neck portion and mechanically removing a conductive paint applied to the neck portion from an end surface of the neck portion to a predetermined range.