KR20060038540A - A sealing/cutting processing apparatus for gas filled glass tubes and method thereof - Google Patents

Abstract

The present invention relates to an apparatus and method for sealing / cutting a gas-sealed glass tube using a laser to simultaneously cut and seal a gas-filled glass tube without leaking gas. A laser for irradiating a laser beam by supplying a laser light source used in processing; A beam guide device for irradiating a laser beam to the glass tube surface; A gas chamber for supplying and storing gas; A glass tube that can be fixed by inserting a glass tube to be processed; A chuck holder for locking and releasing the glass tube; A gas transfer pipe for transferring gas; On-off automatic valve for gas injection to inject gas into the glass tube; A first glass tube support to prevent the glass tube fixed to the glass tube from bending; A rotary chuck inserted into the glass tube chuck and connected to the other side of the fixed glass tube to rotate the glass tube; A rotating belt connected to the glass tube chuck and the rotary chuck to rotate the glass tube; A second glass tube support to prevent bending during glass tube transfer; A rotating motor and a feeding stage for rotating the rotating belt and conveying the glass tube a predetermined distance; And a controller for intermittently irradiating the laser beam to the glass tube.

Laser, sealing / cutting process, on-off irradiation, glass tube

Description

A device and method for sealing / cutting a gas-sealed glass tube using a laser {A SEALING / CUTTING PROCESSING APPARATUS FOR GAS FILLED GLASS TUBES AND METHOD THEREOF}             

1 is a view showing that the cut surface is sucked by the pressure difference inside / outside the glass tube,

2 (a) is a view showing a glass tube shape when a laser is continuously scanned;

       (b) is a waveform diagram for continuous laser scanning;

3 (a) is a view showing a glass tube shape when the laser is intermittently scanned,

       (b) is a waveform diagram for laser intermittent scanning,

4 is a view for explaining the configuration of the device for sealing / cutting the gas-sealed glass tube using a laser,

FIG. 5 is a block diagram illustrating a method of sealing / cutting a glass tube filled with a gas according to the present invention using a laser.

*** Explanation of symbols on main parts of drawing ***

1: laser 2: laser beam

3: beam guide device 4: gas chamber

5: glass tube 6: chuck holder

7: glass tube 8: gas tube

9 solenoid valve 10 first glass tube support

12: rotating chuck 13: rotating belt

15 second glass tube support 16 rotary motor and feed stage

17 shielding gas inlet 18 laser beam

19: glass tube

The present invention relates to an apparatus and method for sealing / cutting a gas-sealed glass tube using a laser.

More particularly, the present invention relates to an apparatus and method for sealing / cutting a gas-sealed glass tube using a laser to simultaneously cut and seal a gas-filled glass tube without leaking gas. .

In recent years, glass materials have been highly utilized due to the development of the display, bio and pharmaceutical industries, and are increasingly being replaced by precision, mass production, and automated processes in existing manual processes.

In particular, glass tube processing plays an important role in the display industry.

Cold Cathode Fluorescent Lamp (CCFL), which is the light source of BLU (Back Light Unit) used in flat panel display (FPD) or notebook, is made of borosilicate micro glass tube.

The lamp is manufactured by placing a gas and an electrode in a glass tube and then sealing it using a torch. Similarly, self-illuminating lamps can be made by inserting a radioactive gas into a fine glass tube and sealing it with a laser, which can be applied to BLU of LCD (Liquid Crystal Display), watches and other display devices.

These self-luminous lamps do not require power supply and have a long lifespan, and thus are expected to have many applications.

To seal the glass tube using a torch, heat is applied to the sealing portion so that the molten glass fills the inside. After filling, cut the glass tube by pulling both ends. Such a process has a problem that it is difficult to perform precise sealing in a case where the area affected by heat is wide and the process time is much longer than that of laser processing, and the glass tube is very fine in diameter.

In addition, the technique using the torch as described above has a problem that the process is almost impossible to cut to a short length.

In addition, the technique using the torch as described above is a manual industrial character produced based on the experience of a skilled worker, and the application of sealing / cutting on a fine glass tube is a very difficult process.

The introduction of laser-sealed glass sealing technology in the early 1980s has been applied to various applications. Glass tube sealing using a conventional laser is a process technology in which one end is simply incident at an oblique angle and sealed or abutting surfaces of two glass plates in a state where no gas is injected.

The sealing / cutting of the fine glass tube has a problem that the symmetry of the cutting surface is inferior because the sealing / cutting is performed without rotation.

In addition, when the pressure difference between the inside and outside of the glass tube is large, the conventional laser sealing technology causes the molten glass to be sucked into the inside, thereby reducing the processing quality or worsening a hole there is a problem in that sealing is impossible.

The present invention has been made to solve the problems of the prior art as described above, the object of the present invention is to fill the inside of the glass tube while the glass is evenly melted by irradiating a laser while rotating the glass tube, unlike the existing process The present invention provides an apparatus and method for sealing / cutting a gas-sealed glass tube using a laser to be sealed and later cut to obtain a clean and symmetrical excellent cut surface in a short time without leakage of internal gas. .

In addition, another object of the present invention is to use a laser to seal the gas-sealed glass tube for encapsulating by reducing the diameter in stages by irradiating the laser on-off (intermittent), cooling after melting, and melting again. It provides a device and a method for cutting / cutting.                         

In addition, another object of the present invention is to minimize the area affected by heat by shortening the sealing / cutting time to enable a fine sealing / cutting of a few mm length, such as precision control and reproducibility is excellent automation and mass The present invention provides an apparatus and a method for sealing / cutting a gas-sealed glass tube using a laser.

One embodiment of the present invention proposed to solve the above technical problem, the laser supplying a laser light source used in the processing to irradiate a laser beam; A beam guide device for irradiating a laser beam to the glass tube surface; A gas chamber for supplying and storing gas; A glass tube that can be fixed by inserting a glass tube to be processed; A chuck holder for locking and releasing the glass tube; A gas transfer pipe for transferring gas; On-off automatic valve for gas injection to inject gas into the glass tube; A first glass tube support to prevent the glass tube fixed to the glass tube from bending; A rotary chuck inserted into the glass tube chuck and connected to the other side of the fixed glass tube to rotate the glass tube; A rotating belt connected to the glass tube chuck and the rotary chuck to rotate the glass tube; A second glass tube support to prevent bending during glass tube transfer; A rotating motor for rotating the rotating belt; A transport stage for transporting the glass tube over a certain distance; And a controller for intermittently irradiating the laser beam to the glass tube.

In addition, another embodiment of the present invention, in the method of sealing / cutting the glass tube in which the gas is injected, the first step of fixing the glass tube to be processed in the glass tube; A second step of rotating the glass tube fixed to the glass tube; And a third step of intermittently irradiating a laser beam to a predetermined portion of the rotating glass tube.

And, the irradiation range of the laser beam irradiated in the third step is preferably determined after determining the amount of glass to be melted using the diameter and thickness of the glass tube.

In the third step, the number of times of interruption of irradiation of the laser beam is preferably increased as the ratio of the diameter to the thickness of the glass tube increases.

And, the irradiation time of the laser beam in the third step, it is preferable to calculate the amount of glass to be melted once from the irradiation interruption number, and the irradiation time is preferably determined based on the calculated amount of glass.

In the third step, the irradiation stop time of the laser beam is preferably determined by the laser beam irradiation time.

And, the rotation speed of the glass tube of the second step is preferably determined according to the laser irradiation time to rotate at least one or more times during the laser irradiation time.

Hereinafter, the present invention will be described in detail so that those skilled in the art to which the present invention pertains can easily carry out the present invention. The preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Let's explain. Other objects, features, including effects, effects of the present invention will become more apparent from the description of the preferred embodiment.

As shown in FIG. 4, a laser 1 for supplying a laser light source used for processing to irradiate a laser beam, a beam guide device 3 for irradiating the laser beam to the glass tube surface, and a gas A gas chamber 4 for supplying and storing a gas, a glass tube 7 for inserting and fixing a glass tube 5 to be processed, and a chuck holder 6 for locking and releasing the glass tube 7. And a gas pipe 8 for transferring gas, an on-off automatic valve 9 for gas injection to allow gas to be injected into the glass pipe 5, and a glass pipe fixed to the glass chuck 7. 5) the first glass tube support 15 to prevent the bending, and the rotary chuck 12 is connected to the other side of the glass tube (5) inserted and fixed to the glass tube chuck (7) to rotate the glass tube (5) and The rotating belt 13 is connected to the glass chuck 7 and the rotary chuck 12 so that the glass tube 5 is rotated. And a second glass tube supporter 15 to prevent bending during the transfer of the glass tube 5, a rotation motor and a transfer stage 16 for rotating the rotating belt 13 and feeding the glass tube 5 a predetermined distance. And a control unit for allowing the laser 1 to intermittently irradiate the laser beam to the glass tube 5.

The laser 1 is a CO ₂ laser.

The beam guide device 3 consists of a three-axis feed table, a mirror and a lens.

The on-off automatic valve 9 for gas injection is a solenoid valve.

Referring to the operation of the device for sealing / cutting the gas-sealed glass tube configured as described above using a laser as follows.

First, a device for sealing / cutting a gas-sealed glass tube by using a laser includes a first step of fixing a glass tube to be processed to a glass tube, a second step of rotating the glass tube fixed to the glass tube, and a rotation of the glass tube. And a third step of intermittently irradiating the laser beam to a predetermined portion.

First, the glass tube 5 to be processed is fixed to the glass tube 7, and after the sealing / cutting command is input, the control unit controls the rotating motor and the transfer stage 16 so that the glass tube 5 is rotated and the laser 1 is rotated. The laser beam is irradiated to the glass tube 5 to be controlled and rotated.

At this time, when the laser beam is continuously irradiated onto the glass tube 5 as shown in FIG. 2B, when the glass tube 5 is cut, the cut surface is as shown in FIGS. 1 and 2A. It is sucked inward by the external pressure difference.

However, when the present invention is applied and the laser beam is intermittently irradiated onto the glass tube 5 as shown in FIG. 3B, the sealing / cutting part is prevented by the shield gas during the time when the laser beam is stopped. By cooling the glass tube 5 that has been molten, the phenomenon that the cut surface is sucked inwardly as shown in FIG. 3A is significantly reduced.

In other words, when the pressure difference between the glass tube 5 and the outside is large, molten glass is sucked into the glass tube 5, which reduces the processing quality of the cut surface and even causes a hole without being sealed. .

In the process of the present invention, sealing and cutting are simultaneously performed without leakage of internal gas, and the cut surface is perpendicular to the glass tube 5, clean, uniform in thickness, and there is no phenomenon that the molten glass is sucked inward. Moreover, the range in which the glass tube 5 is heated and the heating time are short, and the range affected by heat is small.

On the other hand, the irradiation range of the laser 1 is determined by the diameter of the laser beam and the diameter of the laser beam is determined by adjusting the degree of defocusing of the laser beam using a lens. Since the amount of glass to be melted is determined by the laser irradiation range, the irradiation range is determined by calculating the required melt amount according to the diameter and thickness of the glass tube. That is, the controller determines the amount of glass to be melted in consideration of the diameter and thickness of the glass tube 5 and determines the laser beam irradiation range therefrom. Then, the diameter of the laser beam is adjusted by adjusting the lens.

And, the control unit should determine the laser irradiation time and the number of laser irradiation interruption, because the laser irradiation time determines the amount of glass melted in one time and the laser irradiation interruption frequency determines how many times the laser irradiation. There is a close relationship between each other. In other words, the interruption of the laser irradiation n times is to irradiate the laser n + 1 times, so the total amount of glass to be melted should be divided by n + 1 times and melted. Therefore, the increase in the number of interruptions reduces the survey time. The laser irradiation is performed several times to prevent the sealing / cutting surface from being sucked in by reducing the diameter stepwise as described above. If the number of irradiation is too small, the sealing / cutting surface is sucked in. This takes a long time and increases energy consumption, making it inefficient.

That is, the control unit is cooled by the shielding gas during the time to stop the laser, but if the amount of molten glass is a large amount of time required for cooling because the irradiation time is longer, the down time is longer.

Then, the control unit determines the number of times the laser beam irradiation interruption in consideration of the diameter and thickness of the glass tube. The larger the diameter-to-thickness ratio of the glass tube is, the easier it is to be sucked into the molten glass, so the number of breaks should be increased.

In addition, the control unit calculates the amount of glass to be melted at one time from the irradiation interruption count, and determines the laser beam irradiation time therefrom.

In addition, the controller determines the laser beam irradiation interruption time from the laser beam irradiation time. Since the glass tube is cooled by the shielding gas during the time of stopping the irradiation, the cooling time should be increased when the irradiation time is long and the amount of molten glass increases.

Finally, the control unit rotates the glass tube so that the molten portion is evenly heated. That is, the glass tube should be rotated at least once while the laser beam is being irradiated. Therefore, the shorter the irradiation time, the faster the rotational speed of the glass tube should be. However, if the rotation is too fast, the glass tube is not heated well, so there is an optimum rotation speed.

 Therefore, the present invention has the effect of being able to seal and cut at the same time without leakage of gas by gradually cutting while sealing the glass tube is sealed with a gas of a lower pressure than the outside with a laser sealing.

In addition, when the present invention is applied, there is an effect that the sealing / cutting surface of the processed glass tube is perpendicular to the glass tube axial direction and the thickness is uniform.

In addition, the present invention has the effect that the melt area is minimized to enable precise sealing / cutting to cut fine glass tubes of several mm in diameter to several mm in length.

In addition, the present invention has the effect that the portion affected by the heat of the sealing / cutting site is minimized.

The embodiments disclosed herein are only presented by selecting the most preferred examples to help those skilled in the art from the various possible examples, the technical spirit of the present invention is not necessarily limited or limited only by this embodiment, Various changes and modifications are possible within the scope without departing from the technical spirit of the invention, as well as other embodiments that are equally possible.

Claims (10)

A laser for irradiating a laser beam by supplying a laser light source used in processing; A beam guide device for irradiating a laser beam to the glass tube surface; A gas chamber for supplying and storing gas; A glass tube that can be fixed by inserting a glass tube to be processed; A chuck holder for locking and releasing the glass tube; A gas transfer pipe for transferring gas; On-off automatic valve for gas injection to inject gas into the glass tube; A first glass tube support to prevent the glass tube fixed to the glass tube from bending; A rotary chuck inserted into the glass tube chuck and connected to the other side of the fixed glass tube to rotate the glass tube; A rotating belt connected to the glass tube chuck and the rotary chuck to rotate the glass tube; A second glass tube support to prevent bending during glass tube transfer; A rotating motor and a feeding stage for rotating the rotating belt and conveying the glass tube at a predetermined distance; And A control unit for allowing the laser to irradiate the laser beam to the glass tube intermittently; A device for sealing / cutting a gas-sealed glass tube using a laser. The method of claim 1, wherein the laser, An apparatus for sealing / cutting a gas-sealed glass tube using a laser, characterized in that a CO ₂ laser. The method of claim 1, wherein the beam guide device, A device for sealing / cutting a gas-sealed glass tube using a laser, comprising a three-axis feeder, a mirror, and a lens. According to claim 1, The gas injection on-off automatic valve, A device for sealing / cutting a gas-sealed glass tube using a laser, characterized in that it is a solenoid valve. A method of sealing / cutting a glass tube into which gas is injected, A first step of fixing the glass tube to be processed to the glass tube chuck; A second step of rotating the glass tube fixed to the glass tube; And A third step of intermittently irradiating a laser beam to a predetermined portion of the rotated glass tube; Method for sealing / cutting the gas-sealed glass tube comprising a laser using a laser. The method of claim 5, wherein the irradiation range of the laser beam irradiated in the third step, A method of sealing / cutting a gas-sealed glass tube using a laser, characterized in that the amount of glass to be melted is determined using the diameter and thickness of the glass tube. The method of sealing and cutting a gas-sealed glass tube by using a laser according to claim 5, wherein the number of times of interruption of irradiation of the laser beam in the third step increases as the ratio of diameter to thickness of the glass tube increases. The method of claim 5, wherein the irradiation time of the laser beam in the third step, A method of sealing / cutting a gas-sealed glass tube using a laser, characterized in that the amount of glass to be melted once is calculated from the number of interruptions of irradiation, and the irradiation time is determined based on the calculated amount of glass. The method of claim 5, wherein the irradiation stop time of the laser beam in the third step, A method of sealing / cutting a gas-sealed glass tube by using a laser, characterized by the laser beam irradiation time. The method of claim 5, wherein the rotation speed of the glass tube of the second step, And a method of sealing / cutting a gas-sealed glass tube using a laser, the laser tube being determined according to a laser irradiation time so as to rotate at least one time during the laser irradiation time.

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