JPH0429175B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for applying frit glass to the funnel seal surface of a cathode ray tube.

Conventionally, a coating device for frit glass for a cathode ray tube has a structure as shown in FIG. That is, the funnel 1 is held by a holder 2 and further rotated by an external motor 3 through pulleys 4 and 5. This rotation can be easily and accurately controlled using the position detection switch 6, for example, so that one rotation of the frit glass coating is performed.

The frit dispenser 7, which applies frit glass to the sealing surface 1a of the funnel 1 rotated by the motor 3, has a frit glass 8 inside, and a stirring blade 9 for preventing the frit from deteriorating over time is driven by an external motor 10. It is stirred through gears 11 and 12, high-pressure air 13 is added from the outside, and needle 1
4 can be raised and lowered by an air cylinder 15 to open and close the nozzle section 16. The frit dispenser 7 also includes a guide roller 17 for guiding the inside of the funnel sealing surface 1a, a guide shaft 18 for guiding the dispenser 7 in parallel, and a slide bearing 19. It is now possible to accurately follow changes in the position of. Furthermore, by knowing the position of the sealing surface, the speed of the motor 3 is controlled, so that a uniform amount of frit glass can be applied over the entire circumference.

However, in such a conventional device, as shown in FIG. 2, when the nozzle 16 is closed by the needle 14, the frit glass 8a partially remains in the nozzle hole, and moreover, the frit glass 8 dries extremely rapidly. Since it is formulated in such a way that it loses its fluidity when it is applied to the fritted glass, when it is time to start coating the next time, as shown in FIG. Since it protrudes to the outside of the sealing surface 1a and sag, there is a drawback that it is necessary to obtain it or use another automatic machine to scrape off the overlapping portion 20 with a spatula or the like.

SUMMARY OF THE INVENTION An object of the present invention is to provide a frit glass coating apparatus that does not require modification after coating the frit glass.

An embodiment of the present invention will be described below with reference to FIG. Note that the same or equivalent members as in FIG. 1 are designated by the same reference numerals, and their explanations will be omitted. The nozzle 16 of the needle 14 and the engaging portion 14a are connected by a tapered portion 14a ₁ whose diameter decreases downward, and a straight line with a smaller diameter that extends downward from the lower end of the tapered portion 14a ₁ in a substantially straight line. This engaging portion _14a
is made to match the inner shape of the opening 16a of the nozzle 16. As a result, the frit glass in the needle hole is completely pushed out by the tip portion 14a every time the coating is completed, so that it is possible to prevent the frit glass from sagging due to swelling at the overlapped portion of the coating. Furthermore, since the shape of the portion of the opening 16a of the nozzle 16 that engages with the linear portion _14a2 is flat, the shape of the frit glass that is discharged is uniform. Furthermore, even in the unlikely event that a buildup occurs, the high-pressure air nozzle 2
By blowing high pressure air 22 from 1,
Brush off the binder on the surface to eliminate fluidity and prevent dripping.

According to the present invention, since it is possible to prevent the frit glass from sagging in the overlapping portion of coating, it is possible to omit the work of correcting the overlapping portion after coating, which was conventionally necessary. Another advantage is that it is now possible to fully automate the frit glass coating process, which has been difficult in the past due to the hindrance of correction work.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway front view of a conventional frit glass coating device, Fig. 2 is a sectional view of the main part of Fig. 1,
FIG. 3 is an explanatory diagram for explaining the overlapping portion after conventional frit glass coating, and FIG. 4 is a sectional view of a main part showing an embodiment of the frit glass coating apparatus according to the present invention. DESCRIPTION OF SYMBOLS 1...Funnel, 1a...Funnel seal surface, 7...Flit dispenser, 8...Flit glass, 14...Needle, 14a...Tip, 16...Nozzle.

Claims (1)

[Claims] 1. A frit glass coating device that applies frit glass to the funnel seal surface of a cathode ray tube using a frit dispenser having at least a container portion for storing frit glass and a nozzle, the coating device being disposed within the frit dispenser and having a drive mechanism. The needle is provided with a needle that moves up and down to engage the nozzle of the dispenser to open and close it, the needle having a first diameter in the container portion and an engagement portion with the nozzle. The lower part has a tapered part whose diameter decreases downwardly, and a straight part having a second smaller diameter that extends downward from the lower end of the tapered part in a substantially straight line, and The outer shape of the nozzle is formed to match the shape of the engaging part of the nozzle, and the outer shape of the nozzle is a cylinder whose height is smaller than the lower part of the needle and whose outer diameter is larger than the first diameter of the needle. , the diameter of the container portion is the smallest at a portion combined with the nozzle, and a high-pressure air nozzle is provided for spraying high-pressure air only to the overlapping portion of the frit glass at the start and end of application of the frit glass on the funnel seal surface. Fritted glass coating equipment.