JPH0787080B2 - Frit glass coating equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a frit glass coating device for coating frit glass on a frit seal surface of a funnel in a manufacturing process of a cathode ray tube, particularly a color cathode ray tube.

[Conventional technology]

Generally, as shown in FIG. 4, a color cathode ray tube has a funnel 4 as a means for sealing the panel 2 and the funnel 4 together.
The frit glass 10 is coated with frit glass 10. In the figure, 1 is a fluorescent film, 3 is a shadow mask, and 5
Is a neck, 6 is a stem, 7 is an electron gun structure, and 15 is an anode.

Conventionally, this type of frit glass coating device is disclosed in Japanese Patent Laid-Open No. 57-2.
As disclosed in Japanese Patent No. 09669, as shown in FIG. 6, the conventional device has the funnel 4 supported by the rotary table 13 with the frit seal surface 4a facing upward, and the servomotor 16 of the drive device 15 causes the gear 17, The funnel 4 is rotated about the rotation axis x via 18, and the rotation angle is constantly detected by the rotary encoder 20 and the seal surface 4a is constantly detected by the photo array camera 22. The nozzle 24 of the frit tank 25 is arranged at a position facing the rotation axis x of the funnel 4 from the set position of the photo array camera 22 in the direction of 180 °, for example.
A winding operation processing device 32 issues a command in response to an input signal of 22 and is controlled by a servo motor 30 and a ball screw 28 of a nozzle position adjusting device 27 so that the nozzle 24 is always a frit seal surface.
Frit glass was applied so as to be positioned at the center of 4a in the width direction.

FIG. 5 shows the funnel at the stage of applying the frit glass. The funnel portion conductive graphite 9 and the neck conductive graphite 8 are applied to the inner peripheral surfaces of the funnel 4 and the neck 5, respectively.

[Problems to be Solved by the Invention]

The conventional frit glass coating device described above has the following problems. That is, (1) In the method of controlling the position of the nozzle 24 while constantly inputting the data of the photo array camera 22, since the position of the nozzle 24 is adjusted each time while performing the calculation processing, the position of the funnel 4 can be adjusted. I can not rotate faster,
Application takes time.

(2) The viscosity of the frit glass discharged from the nozzle 24 reaches the frit seal surface 4a with respect to the movement of the nozzle 24 due to the viscosity. For this reason, at the funnel corner portion where the moving direction of the nozzle 24 suddenly changes, the frit is applied to the inside of the frit seal surface 4a and drips from the frit seal surface, and the necessary frit amount cannot be secured.

(3) The frit glass needs to be applied uniformly over the entire circumference of the frit seal surface 4a, and there must be no uncoated portion on the frit seal surface 4a.

In the frit glass coating device, especially the coating start position and the coating end position match, there is no uncoated portion at this portion, and the coated portions overlap too much, and excess frit glass hangs inside and outside the frit seal surface 4a. It must be applied so that it does not drip. However, the frit glass supply is normally a sealed frit tank 25.
Further, the air is pressure-fed to the nozzle 24, and the on-off valve provided inside the nozzle 24 is opened to perform the discharge. For this reason, the air pressure continues to be applied while the on-off valve is closed, and the pressure-feeding pressure of air rises somewhat, and when the on-off valve is opened at the coating start position, the frit glass is vigorously discharged. Therefore, the amount of the frit glass is generally larger at the application start position than at other portions, and the frit glass further overlaps with the frit glass at the end of the application, so that the frit seal surface easily hangs inside and outside. Further, since the frit glass has a property of being easily dried and solidified, if the time the application is completed and the on-off valve is closed for a long time, the frit glass at the tip of the nozzle 24 dries, and then the on-off valve is opened. When this happens, the phenomenon that the start of the frit glass is delayed occurs. Therefore, for example, if the control of the on-off valve is opened at a certain point on the frit seal surface and closed at a certain point, the variation in the arrival of the funnel at the application position will be the variation in the closing time of the on-off valve. This affects the dry state of the frit glass at the tip of the nozzle, causes variations in the coating start position, and causes a problem in that the frit glass does not succeed at the coating end position.

An object of the present invention is to provide a frit glass coating device that solves the above problems.

[Differences from the Prior Art of the Invention]

In contrast to the conventional frit glass coating device described above, the present invention uses a variable sequence robot in the coating device body, provides a detection mechanism for frit glass on the frit seal surface, and starts and ends frit glass coating. The difference is that the operating speed of the on-off valve for control can be changed independently.

[Means for Solving the Problems]

In order to achieve the above object, a frit glass coating device according to the present invention includes a funnel positioning mechanism and a variable sequence robot, and a frit glass is provided on a frit seal surface of a funnel for sealing a cathode ray tube panel and a funnel. A frit glass coating apparatus for coating a funnel positioning mechanism having a funnel support portion and a neck chuck, wherein the funnel support portion abuts the funnel outer peripheral surface to perform positioning support. , The funnel neck is positioned and supported, and the variable sequence robot moves the coating nozzle along the long side and the short side of the frit seal surface. The movement of the coating nozzle with respect to the side and the short side should be The movement of the coating nozzle is controlled in a curved shape close to a straight line, and the movement of the coating nozzle with respect to the corner portion where the long side and the short side of the frit seal surface intersect is circularly interpolated so as to move to the outside of the frit seal surface in anticipation of ingress. The movement control is performed in an arc shape.

Further, it has a detection mechanism for detecting the frit glass applied on the frit seal surface, and the detection mechanism controls the application end position by detecting the application start position of the frit glass.

Further, it has an opening / closing valve control mechanism, and the opening / closing valve control mechanism independently changes the operating speed of the opening / closing valve for controlling the start and end of coating of the frit glass provided inside the coating nozzle. It is a thing.

〔Example〕

 Next, the present invention will be described with reference to the drawings.

FIG. 1 is a front view showing a frit glass coating apparatus according to the present invention.

In this embodiment, a Cartesian coordinate type robot 36 having an X axis 33, a Y axis 34 and a Z axis 35 as a variable sequence robot.
The dispenser 37 is fixed to the tip of the Z-axis 35 (hereinafter abbreviated as robot), and the funnel 4 is placed in front of it (direction of movement).
Frit glass 10 applied on the frit seal surface 4a of
A photoelectric sensor 39 for detecting is arranged.

Further, when the funnel 4 is carried to the frit glass coating position by the pallet 40, the four funnel supporting portions 41 that have been waiting are lifted by the cylinders 42 and come into contact with the funnel 4 to lift the funnel 4. By this lifting operation, the rotation direction around the tube axis of the funnel 4 is modified, and thereafter, the neck 5 is pressed by the neck chuck 43, and together with the positioning of the funnel support portion 41, the tube axis direction of the funnel 4 and Positioning in the direction of rotation around the tube axis is completed.

There is a method of positioning the funnel 4 in the rotational direction around the tube axis by supporting three alignment points on the outer periphery of the funnel. In this method, the dimension of the alignment point is the size of the funnel 4. Since it varies depending on the situation, there arises a problem that it is difficult to share it in the case of an automated line for multi-product production.

In the method of supporting the outer periphery of the funnel of the present invention, the funnel support portion 41 is brought into contact with the portion where the cross-sectional shape of the outer periphery of the funnel is substantially rectangular, so that the funnel support portion 41 can be commonly used in several sizes.

In the case of this embodiment, the distance between the four outer peripheral support portions is about 180 mm on the long side direction side of the funnel 4 and about 120 mm on the short side direction side.
In the setting of, it is possible to share from 10 inches to 16 inches.

Next, the coating operation by the robot 36 will be described in detail.

When the positioning of the funnel 4 is completed, the robot 36 can be operated by the teaching data previously input to the robot 36.
The operation of starts. First, the dispenser 37 fixed to the Z axis 35 of the robot 36 moves from the standby position to the frit seal surface 4a.
Move to the vicinity of the upper coating start position 44. After that, the on-off valve 45 is opened and the frit glass 10 is discharged while moving on the seal surface 4a. Frit glass 10 is dispensed from a frit tank (not shown) via tube 46 to dispenser 37.
Is being supplied to. The movement locus of the dispenser 37 will be described with reference to FIG. 2. The long side 47 and the short side 52 have a small curvature and have a curved shape close to a straight line. Therefore, the dispenser 37 is moved along the center of the frit seal surface 4a. By doing so, the frit glass 10 can be applied to the center of the frit seal surface. At this time, the interpolation function (linear interpolation, circular interpolation, etc.) of the robot 36 teaches the start point, the end point and the points near the middle of each side and moves them by circular interpolation, or the teaching points are finely specified by linear interpolation. You may move it.

Next, in the corner part, the curvature of the center of the frit seal surface 4a is about R20 to R30 (depending on the product type). As described above, if the dispenser 37 is moved along the center of the frit seal surface 4a, the frit may be changed. Since the glass 10 is applied toward the inside, the teaching is performed by circular interpolation so that the movement locus 48 of the dispenser 37 is moved to the outside of the frit seal surface 4a in anticipation of entering the inside.

The extent to which this movement locus 48 is shifted to the outside is the frit seal surface.
Various conditions such as the distance from the nozzle 4a to the nozzle 47 and the viscosity of the frit glass 10 affect it, so it is difficult to determine it by a desktop calculation. Since it is possible to make fine corrections by teaching while performing, it is easy to find the optimum position. Reference numeral 50 is a starting locus, and 51 is an ending locus.

In FIG. 1, when the dispenser 37 moves around the frit seal surface 4a and moves to the vicinity of the coating start position 44, the photoelectric sensor 39 searches for the coating start position.

The photoelectric sensor 39 is fixed in a direction in which the frit seal surface 4a is moved ahead of the dispenser 37 at a distance of, for example, about 20 mm from the dispenser 37 on one side where the application start position is located. Therefore, the photoelectric sensor 39 moves to the coating start position 44
The dispenser 37 is at a distance of 20 mm before the application start position at the time of detecting. The distance between the photoelectric sensor 39 and the dispenser 37 is the position where the photoelectric sensor 39 starts the application.
Due to the electrical and mechanical delay between the detection of 44 and the closing of the on-off valve 45, it is determined by the distance that the frit glass 10 is applied while the dispenser 37 is moving during this time. Therefore, the photoelectric sensor 39 is fixed by the dispenser 37.
It is desirable to have a mechanism capable of fine adjustment in the moving direction of.

As described above, the photoelectric sensor 39 detects the coating start position 44, the on-off valve 45 is closed by this signal, and the frit glass is closed.
Stop dispensing 10. Since the dispenser 37 is also moving during this time, the distance between the photoelectric sensor 39 and the dispenser 37 is adjusted so that the discharge is stopped at the position where the frit glass 10 exactly overlaps at the coating start position 44. By using the photoelectric sensor 39, even when the coating start position 44 varies, the opening / closing valve 45 closing position is always closed at a constant distance from the coating start position, which enables stable coating. Become.

Further, the present invention has the following mechanism in order to stabilize the overlapping condition of the frit glass at the coating start position.

As described above, when the on-off valve 45 opens, the dispenser
The increase in the pressure in 37 increases the application amount of the frit glass 10, and when the on-off valve 45 closes, the on-off valve 45 pushes the frit glass 10 to increase the application amount. Therefore, in the embodiment according to the present invention, as shown in FIG. 3, the on-off valve 45 is driven by the double-acting cylinder 49, and the speed controllers 49a and 49b are attached in both directions of opening and closing to open and close the on-off valve. It is set so that the operating speed can be adjusted independently. By doing so, for example, when the on-off valve 45 is opened, the speed controller 49a is throttled, and if the operating speed is slowed, the flow passage cross-sectional area of the frit glass gradually increases until the on-off valve 45 is fully opened. It is possible to apply a proper amount of frit glass by exactly canceling out the phenomenon that the application amount increases due to the increase in pressure. Similarly, when closing the on-off valve 45,
By restricting the speed controller 49b and slowing the operating speed of the on-off valve 45, it is possible to prevent the frit glass 10 from being gradually pushed out and locally increasing the coating amount.

Further, in combination with the above-mentioned mechanism for adjusting the operation speed of the opening / closing valve, the moving speed of the dispenser can be changed by the teaching of the robot, so that finer control can be performed.

In the present embodiment, the method of supplying the frit glass from the frit tank (not shown) to the dispenser 37 through the tube 46 is used, but the frit tank is fixed to the robot and the nozzle 47 is provided at the bottom of the frit tank. The present invention is also effective in the case where an on-off valve is provided inside the frit tank for coating.

〔The invention's effect〕

As described above, according to the present invention, it is possible to easily apply the frit glass to the center of the frit seal surface by using the variable sequence robot. Also,
By supporting the outer circumference of the funnel, the funnel positioning mechanism enables common use of funnels of several sizes without changing the distances of the four outer circumference support portions. Further, by providing the frit detection sensor and the mechanism for adjusting the operating speed of the opening / closing valve, there is an effect that the joint portion of the frit glass at the coating start position and the coating end position can be stably coated.

[Brief description of drawings]

FIG. 1 is a front view showing a frit glass coating device of the present invention, FIG. 2 is a plan view showing a movement trajectory of a dispenser, FIG. 3 is a partial sectional view showing a structure of a dispenser according to the present invention, and FIG. FIG. 5 is a vertical cross-sectional view showing the structure of the cathode ray tube, FIG. 5 is a vertical cross-sectional view showing the form of the funnel at the stage when the frit glass is applied, and FIG. 6 is a perspective view showing a conventional frit glass applying apparatus. 4 …… Funnel, 4a …… Frit seal surface 10 …… Frit glass 36 …… Cartesian coordinate type robot (variable sequence robot) 37 …… Dispenser, 39 …… Photoelectric sensor 41 …… Funnel support

Claims (3)

[Claims] 1. A frit glass coating apparatus having a funnel positioning mechanism and a variable sequence robot, for coating frit glass on a frit seal surface of a funnel for sealing a cathode ray tube panel and the funnel, the funnel comprising: The positioning mechanism has a funnel support portion and a neck chuck, the funnel support portion contacts the funnel outer peripheral surface to position and support the neck chuck, and the neck chuck positions and supports the funnel neck. The variable sequence robot moves the coating nozzle along the long side and the short side of the frit seal surface, and the variable sequence robot moves the coating nozzle with respect to the long side and the short side of the frit seal surface with a small curvature. , The movement of the frit seal surface is controlled by moving it to a curved shape that is almost straight. It is characterized in that the movement of the coating nozzle with respect to the corner portion where the side and the short side intersect is controlled to move in an arc shape by arc interpolation so as to move to the outside of the frit seal surface in anticipation of intrusion. Frit glass coating device. 2. A detection mechanism for detecting frit glass applied on the frit seal surface, wherein the detection mechanism controls the application end position by detecting the application start position of the frit glass. The frit glass coating device according to claim 1, further comprising: 3. An opening / closing valve control mechanism, wherein the opening / closing valve control mechanism controls an opening / closing valve for controlling the start and end of coating of the frit glass provided inside the coating nozzle independently of the operating speed at the time of opening / closing. The frit glass coating device according to claim 1, wherein the frit glass coating device is variable.