JPS5910523B2 - Cathode ray tube internal conductive film shaping device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a cathode ray tube internal conductive film shaping device.

It is common practice to deposit and form an internal conductive film made of graphite over a region extending from the funnel part to a part of the neck part of a cathode ray tube bulb. If provided in the form of a conductive film, a conductive film will be formed not only on the inner surface of the funnel portion but also on the entire inner surface of the neck portion.

Therefore, it is necessary to perform shaping to remove a part of the conductive film formed on the inner surface of the neck part. Conventionally, for example, as shown in FIG. Cleaning liquid spouted from fountain 3 and nozzle 2
A shaping means is adopted in which unnecessary conductive film portions 4 are washed and wiped with water using a flat rubber piece (not shown) attached to the holder.

However, in this case, it is not easy to maintain the neck part 1 and the nozzle 2 inserted therein coaxially during the washing period due to water pressure, etc., and if eccentricity or inclination occurs here, the conductive film may adhere. The boundary between the area and the non-adhesive area is disturbed, resulting in an adverse effect on the characteristics of the cathode ray tube, especially the high pressure characteristics.

Note that 5 indicates a funnel portion, and 6 indicates an internal conductive film.

The present invention has been made with the above-mentioned points in mind, and the cathode ray tube internal conductive film shaping device of the present invention will be described below along with embodiments shown in the drawings.

In FIG. 2 showing the graphite coating process, a valve 7 consisting of a funnel part 5 and a neck part 1 is placed on a stand 8 with the large-diameter opening end of the funnel part 5 facing upward, and is supplied through a pipe 9. The resulting graphite suspension is transferred to the funnel section 5.
and the inner surface of the neck portion 1 to form an internal conductive film 10.

The excess graphite suspension is then discharged through a pipe 11 communicating with a liquid recovery container (not shown).

The internal conductive film 10 coated on the bulb I is dried by far infrared rays emitted from the drying heater 12 and hot air sent out through the air pipe 13, as shown in FIG. 1, the nozzle 15 of the internal conductive film shaping device 14 according to the present invention is inserted.

As shown in FIGS. 4 and 5, the nozzle 15 has a dome-shaped tip, and a side wall near the tip has three water spouts 16.

This nozzle 15 has one side embedded in the side wall of the nozzle 15.
It can be pivoted together with the individual flexible wiping strips 17 in the direction of the arrow shown.

The three flexible wiping strips 1γ are made of rubber or the like, and are attached so as to start near both sides of the water fountain 16 and spiral around the outer peripheral surface of the side wall in the opposite direction to the axis rotation. ing.

In the process of drying the internal conductive film 10 by the heat rays radiated from the drying heater 12 and the hot air sent from the air pipe 13, cleaning liquid is sprayed from the water fountain 16 of the noise 15, thereby removing unnecessary parts inside the neck part 1. Remove the conductive film part by washing with water.

At this time, instead of rotating the nozzle 15 in the direction of the arrow shown in the figure, the nozzle 15 may be fixed and the neck part 1 rotated in the direction opposite to the arrow shown in the figure. 15 is relatively rotated in the direction of the illustrated arrow.

According to the present invention, in particular, the plurality of flexible wiping strips provided on the nozzle have a spiral shape that starts near both sides of the water spout provided on the nozzle side wall and goes around the outer peripheral surface of the nozzle side wall. Moreover, since the nozzle rotates in a direction opposite to the direction of rotation, it is possible not only to wipe the non-conductive film portion with the wiping strip up to the boundary line with the conductive film portion. The coaxiality between the nozzle axis and the valve axis can always be maintained well, and the risk of disturbing the boundary line or splashing the cleaning liquid onto the conductive film portion due to the inclination of the nozzle axis can be prevented.

Furthermore, the spirally rotated wiping strip has the effect of forcibly pushing down the cleaning liquid flowing along it, so that the splashing of the cleaning liquid on the conductive film side is further suppressed.
Furthermore, unnecessary conductive film material is efficiently discharged together with the cleaning liquid, making it possible to obtain a cathode ray tube with excellent high-pressure characteristics.

[Brief explanation of drawings]

FIG. 1 is a side view showing a state in which a conventional cathode ray tube internal conductive film shaping device is used to shape the internal conductive film, FIG. 2 is a perspective view schematically showing the graphite suspension coating process, and FIG. 3 is a diagram showing the present invention. FIG. 4 is a perspective view of a main part of the shaping apparatus of the present invention, and FIG. 5 is a cross-sectional view of the main part. DESCRIPTION OF SYMBOLS 1... Neck part, 5... Funnel part, 14... Shaping device, 15... Nozzle, 16... Fountain port, 17 ...Flexible wiping strip.

Claims (1)

[Claims] 1. A side wall of a nozzle that is inserted from the open end side into a valve neck portion on which a conductive film is applied and formed on the inner circumferential surface, and rotates about the neck portion to remove the conductive film portion on the open end side by washing with water. A plurality of flexible wiping strips are attached that start from near both sides of the water fountain formed in the side wall and spiral around the outer peripheral surface of the side wall in a direction opposite to the axis rotation. A device for shaping a conductive film inside a cathode ray tube.