Device and method for removing small bubbles in optical fiber coating

Abstract

The invention provides a device and method for removing small bubbles in an optical fiber coating, the device comprises a coating storage tank and a coating buffer tank, a booster pump and a large bubble detector are arranged on a main pipeline, a material return pipe is arranged behind the liquid flow direction of the large bubble detector, the main pipeline is connected with the coating buffer tank through a feeding pipe, and the feeding pipe is connected with the coating buffer tank through a discharging pipe. A liquid level sensor is arranged in the coating buffer tank, the coating buffer tank is provided with a heater or / and a vacuum pump for vacuumizing the coating buffer tank, and the coating buffer tank is connected with the coating cup through a discharge pipe. When the large bubble detector gives an alarm, paint with bubbles flows back into the paint storage tank through the paint backflow pipeline, and after the large bubble detector stops giving the alarm, the paint continues to flow forwards into the paint buffer tank in the main pipeline. After bubbles in the coating buffer tank are removed in a heating or / and vacuumizing mode, the coating is supplied to the coating cup. The optical fiber coating defect caused by the fact that bubbles enter the coating cup is avoided, and therefore the optical fiber coating quality is improved.

Description

Technical Field

[0001] The invention relates to the technical field of optical fiber production, and in particular to a device and method for removing small bubbles in optical fiber coating. Background Art

[0002] Fiber drawing is one of the basic steps in manufacturing optical fiber. The optical fiber preform is fed into an induction heating furnace at a temperature of more than 2000 degrees by a feeding system for heating. After the preform is softened, it is pulled out from the lower opening of the induction heating furnace in the form of a filament under the action of gravity. After natural cooling and forced cooling, before the microcracks on the surface of the bare optical fiber glass begin to expand due to the influence of the external environment, two or more layers of coating are quickly applied to protect the bare optical fiber. Fiber coating is a key link in optical fiber manufacturing. During the optical fiber coating process, if bubbles are mixed in the coating, it will cause bulging or depression of the optical fiber coating. The coating defects will affect the mechanical strength, environmental performance and continuous performance of the optical fiber, and affect the service life of the optical fiber. Therefore, in the production process, the optical fiber with coating defects needs to be rewound onto the optical fiber reel separately in the screening process for scrapping, which not only affects the optical fiber quality and screening time, but also increases the optical fiber manufacturing cost. Generally, there are two reasons for the introduction of bubbles into the coating: the first is the air brought into the coating cup when the coating mold is disassembled and reinstalled; the second is the bubbles generated when the coating is poured from the coating storage barrel into the coating buffer tank under the action of the booster pump of the central feeding system. How to reduce the bubbles in the coating or eliminate the bubbles in time is the key to reducing the scrapping of optical fiber coating.

[0003] In the published patent documents, there are already some methods to solve the problem of bubbles in the coating. Chinese patent CN 114988722A discloses an optical fiber coating device with online monitoring and bubble removal functions. In the optical fiber drawing speed-up stage, the bubbles in the coating are monitored online and the coating with bubbles is discharged from the coating cup in time, thereby avoiding coating defects caused by the coating with bubbles being applied to the optical fiber. It is mainly suitable for reducing the bubbles generated by the air brought into the coating cup when the coating mold is disassembled and reinstalled during the optical fiber speed-up stage, but it cannot reduce the bubbles generated when the coating is poured from the coating storage barrel into the coating buffer tank under the action of the booster pump of the central feeding system during the drawing process. Therefore, we propose a new device and method for removing bubbles in the coating. Summary of the invention

[0004] The purpose of the present invention is to provide a device and method for removing small bubbles in optical fiber coating, which can remove bubbles generated when the coating is poured from a coating storage barrel into a coating buffer tank under the action of a booster pump of a central feeding system, thereby reducing the scrapping of optical fiber coating defects and reducing the manufacturing cost of optical fiber.

[0005] The present invention is achieved in that: The present invention provides a device for removing small bubbles in optical fiber coating, comprising a coating storage tank and a coating buffer tank connected to the coating storage tank through a main pipeline, characterized in that a booster pump and a large bubble detector are provided on the main pipeline, and a return pipe is also provided behind the liquid flow of the large bubble detector, one end of the return pipe is connected to the main pipeline, and the other end is connected to the return port of the coating storage tank, the main pipeline is connected to the coating buffer tank through a feed pipe, a liquid level sensor is provided in the coating buffer tank, the coating buffer tank is equipped with a heater and / or a vacuum pump for evacuating the coating buffer tank, and the coating buffer tank is connected to a coating cup through a discharge pipe.

[0006] According to the above technical solution, there are at least two paint buffer tanks, which are connected in parallel. Their inlets are also connected to the main pipeline through the feed port, and their outlets are connected to the coating cup through the discharge pipe. Each paint buffer tank is equipped with a liquid level sensor and a vacuum pump.

[0007] According to the above technical solution, each paint buffer tank is also connected to an air compressor through a compressed air pipeline.

[0008] According to the above technical solution, the liquid level sensor includes a low-level liquid level sensor and a high-level liquid level sensor.

[0009] According to the above technical solution, a coating filter is also provided on the discharge pipe, and the outlet of the filter is connected to the coating cup.

[0010] According to the above technical solution, an electronic valve is provided on the return pipe.

[0011] According to the above technical solution, electronic valves are arranged on the feed pipe, the discharge pipe, the vacuum pipe and the compressed air pipe.

[0012] According to the above technical solution, the coating buffer tank is heated by water bath heating.

[0013] A method for removing small bubbles in optical fiber coating using the above-mentioned device for removing small bubbles in optical fiber coating is characterized by comprising the following steps: S1. The paint in the paint storage tank is pumped into the paint buffer tank under the action of the booster pump. Since there is a large bubble detector in the pipeline behind the booster pump, when the large bubble detector alarms, the paint with bubbles will flow back to the paint storage tank through the paint return pipeline. When the large bubble detector stops alarming, the paint continues to flow forward into the paint buffer tank in the main pipeline. S2. After removing the bubbles in the coating buffer tank by heating and / or vacuuming, the coating cup is supplied with materials.

[0014] According to the above technical solution, two groups of parallel paint buffer tanks are provided. When one group of paint buffer tanks is fed by a booster pump, the other group of paint buffer tanks supplies material to the coating cup, and the two groups feed and supply material alternately.

[0015] The beneficial effects of the present invention are: 1. The present invention adds a coating buffer tank to the central tank system, heats and / or evacuates the coating buffer tank to remove small bubbles in the coating, and then inputs the coating into the coating cup, thereby avoiding bubbles entering the coating cup to cause optical fiber coating defects, thereby improving the optical fiber coating quality. 2. The present invention provides two buffer tanks, which can remove bubbles in the coating online by heating and vacuuming. After the paint in the buffer tank is treated to remove bubbles, it is alternately fed to the coating cup, thereby improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 A schematic diagram of a structure for removing small bubbles from optical fiber coating provided by an embodiment of the present invention.

[0018] In the figure: 1. Paint storage tank; 2. Paint booster pump; 3. Bubble detector; 4. Paint return pipe electronic valve; 5. B tank feed pipe electronic valve; 6. B tank high-level paint level sensor; 7. B tank low-level paint level sensor; 8. B tank discharge pipe electronic valve; 9. B tank compressed air pipe electronic valve; 10. B tank vacuum pump pipe electronic valve; 11. B tank vacuum pump; 12. Electronic valve for the feed pipe of tank A; 13. High-level paint level sensor for tank A; 14. Low-level paint level sensor for tank A; 15. Electronic valve for the discharge pipe of tank A; 16. Electronic valve for the compressed air pipe of tank A; 17. Electronic valve for the vacuum pump pipe of tank A; 18. Vacuum pump of tank A; 19. Paint filter; 20. Coating cup; 21. Main pipe; 22. Return pipe; 23. Feed pipe of tank A; 24. Feed pipe of tank B; 25. Discharge pipe of tank A; 26. Discharge pipe of tank B; 27. Vacuum pipe of tank A; 28. Compressed air pipe of tank A; 29. ​​Compressed air pipe of tank B. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0022] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the product of the application is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0023] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0024] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0026] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0027] like Figure 1 As shown, this embodiment provides a device for removing small bubbles in optical fiber coating, including a coating storage tank 1, a coating buffer tank connected to the coating storage tank 1 through a main pipe 21, a booster pump 2 and a large bubble detector 3 are provided on the main pipe 21, and a return pipe 22 is also provided behind the liquid flow of the large bubble detector, one end of the return pipe 22 is connected to the main pipe 21, and the other end is connected to the return port of the coating storage tank 1, the main pipe 21 is connected to the coating buffer tank through a feed pipe 23, a liquid level sensor is provided in the coating buffer tank, the coating buffer tank is equipped with a heater and / or a vacuum pump for evacuating the coating buffer tank, and this embodiment is described by taking the simultaneous configuration of a heater and a vacuum pump as an example, and the coating buffer tank is connected to the coating cup 20 through a discharge pipe 25. In this embodiment, the paint in the paint storage tank 1 is fed to the paint buffer tank under the action of the booster pump 2. Since there is a large bubble detector 3 in the pipeline behind the booster pump 2, when the large bubble detector 3 alarms, the paint return pipeline electronic valve 4 opens, and the paint with bubbles flows back to the paint storage tank 1. When the large bubble detector 3 stops alarming, the paint return pipeline electronic valve 4 closes, and the paint continues to flow forward into the paint buffer tank in the main pipeline. After removing the bubbles in the paint by heating and vacuuming online, the coating cup 20 is fed. In this way, the bubbles generated by the paint being poured from the paint storage tank into the paint buffer tank under the action of the booster pump of the central feeding system can be effectively removed, and the paint with bubbles entering the coating cup to cause coating defects can be avoided, thereby reducing the scrapping of optical fiber coating defects and reducing the manufacturing cost of optical fiber. In the central tank system, the present invention adds a paint buffer tank, heats and vacuums the paint buffer tank to remove small bubbles in the paint, and then inputs the paint into the coating cup, thereby avoiding bubbles entering the coating cup to cause optical fiber coating defects, thereby improving the quality of optical fiber coating.

[0028] In this embodiment, in order to make the pressure and flow rate of the coating buffer tank supplying the coating cup more stable, the coating buffer tank is also connected to the air compressor through a compressed air pipeline, and the compressed air pressure can be adjusted between 0 and 8 bar.

[0029] In order to further improve work efficiency, this embodiment takes the setting of two paint buffer tanks as an example for explanation. Figure 1 As shown, it is divided into a paint buffer tank A and a paint buffer tank B, and the structures and functions of the two are the same. Therefore, the structure and function of the paint buffer tank A are introduced in detail. The paint buffer tank A can tank 50~150kg at a time. The feed port of the paint buffer tank A is connected to the feed pipe 23, and the feed pipe 23 is provided with a paint feed pipeline electronic valve 12. The discharge port of the paint buffer tank A is connected to the discharge pipe 25, and the discharge pipe 25 is provided with a paint discharge pipeline electronic valve 15. The paint buffer tank A is installed with a high-level paint level sensor 13 and a low-level paint level sensor 14. In order to completely remove small bubbles in the paint, the heater configured for the paint buffer tank A adopts water bath heating, and the temperature setting range is 35~60 degrees Celsius. The paint buffer tank A is connected to the vacuum pump 18 through the vacuum pipeline 27, and the vacuum pipeline electronic valve 17 is installed on the vacuum pipeline 27. In order to stably supply the paint in the paint buffer tank A to the coating cup 20, the paint buffer tank A is also connected to a compressed air pipeline 28, and an electronic valve 16 is provided between the paint buffer tank A and the compressed air pipeline, and the compressed air pressure can be adjusted between 0 and 8 bar by the compressor. A filter 19 is provided on the pipeline connected to the coating cup, and the outlet of the filter 19 is connected to the coating cup 20.

[0030] In this embodiment, the inner walls of buffer tanks A and B are equipped with circulating water pipes, which are connected to the water bath circulator. The water in the water bath circulator is heated to a set temperature through a heating element. At the same time, a built-in circulating pump allows water to continuously flow in the water bath circulator and the inner wall pipes of the buffer tank to ensure the uniformity of the water temperature of each part of the buffer tanks A and B.

[0031] This embodiment also provides a method for removing small bubbles in optical fiber coating using the above device, which comprises the following steps: S1, the paint in the paint storage tank 1 can be fed to the paint buffer tanks A and B respectively under the action of the booster pump 2; S2, when the paint buffer tank A is filled, the electronic valve 12 of the feed pipe of the paint buffer tank A is opened, the electronic valve 15 of the discharge pipe of the paint buffer tank A is closed, and the electronic valve 16 of the compressed air pipe of the paint buffer tank A and the electronic valve 17 of the vacuum pipe are closed, and the paint is slowly poured into the paint buffer tank A; S3, when the paint level contacts the high paint level sensor 13, stop feeding the paint buffer tank A, close the electronic valves 12, 15, 16 of the paint buffer tank A, open the vacuum pipe electronic valve 17, and start the vacuum pump 18 to vacuum the paint buffer tank A to remove small bubbles in the paint; S4. After the vacuuming process is completed, the vacuuming pipeline electronic valve 17 of the paint buffer tank A is closed, and the paint buffer tank A waits for activation.

[0032] S5. In the process of feeding paint into the paint buffer tank A, the electronic valve 5 on the feeding pipe 24 of the paint buffer tank B and the electronic valve 10 on the vacuum pipe are closed, and the electronic valve 9 on the compressed air pipe 29 of the paint buffer tank B and the electronic valve 8 on the discharge pipe 26 are opened to supply paint to the coating cup 20; S6, when the coating liquid level in the coating buffer tank B is lower than the low coating liquid level sensor 7, the coating buffer tank B discharge pipe electronic valve 8, the compressed air pipe electronic valve 9 and the vacuum pipe electronic valve 10 are closed, and the coating buffer tank B stops supplying the coating cup 20; S7, the electronic valve of the feed pipeline of the paint buffer tank B is opened, and the paint in the paint storage tank 1 begins to be fed into the paint buffer tank B under the action of the increase pump 2.

[0033] S8 , while the electronic valve 8 of the discharge pipe of the paint buffer tank B is closed, the electronic valve 15 of the discharge pipe of the paint buffer tank A and the electronic valve 16 of the compressed air pipe are opened, and the paint buffer tank A starts to supply the coating cup 20 .

[0034] The present invention is provided with two coating buffer tanks A and B, which can remove bubbles in the coating online by heating and vacuuming. After the coatings in the coating buffer tanks A and B are treated to remove bubbles, they are alternately fed to the coating cup 20. In this way, bubbles generated by the coating being poured from the coating storage tank into the coating buffer tank under the action of the booster pump of the central feeding system can be effectively removed, thereby preventing the coating with bubbles from entering the coating cup to cause coating defects, thereby reducing the scrapping of optical fiber due to coating defects and reducing the manufacturing cost of optical fiber. The embodiments described above are part of the embodiments of the present invention, rather than all of the embodiments. The detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Claims

1. A device for removing small bubbles in optical fiber coating, comprising a coating storage tank and a coating buffer tank connected to the coating storage tank through a main pipeline, characterized in that: A booster pump and a large bubble detector are provided on the main pipeline, and a return pipe is provided behind the liquid flow of the large bubble detector. One end of the return pipe is connected to the main pipeline, and the other end is connected to the return port of the paint storage tank. The main pipeline is connected to the paint buffer tank through a feed pipe, and a liquid level sensor is provided in the paint buffer tank. The paint buffer tank is equipped with a heater and / or a vacuum pump for evacuating the paint buffer tank, and the paint buffer tank is connected to the coating cup through a discharge pipe.

2. The device for removing small bubbles in optical fiber coating according to claim 1, characterized in that: There are at least two paint buffer tanks, which are connected in parallel. Their inlets are also connected to the main pipeline through the feed port, and their outlets are connected to the coating cup through the discharge pipe. Each paint buffer tank is equipped with a liquid level sensor and a vacuum pump.

3. The device for removing small bubbles in optical fiber coating according to claim 2, characterized in that: Each paint buffer tank is also connected to an air compressor through a compressed air pipeline.

4. The device for removing small bubbles from optical fiber coating according to claim 2 or 3, characterized in that: The liquid level sensor includes a low liquid level sensor and a high liquid level sensor.

5. The device for removing small bubbles in optical fiber coating according to claim 3, characterized in that: A coating filter is also provided on the discharge pipe, and the outlet of the filter is connected to the coating cup.

6. The device for removing small bubbles in optical fiber coating according to claim 1 or 2, characterized in that: An electronic valve is provided on the return pipe.

7. The device for removing small bubbles in optical fiber coating according to claim 3, characterized in that: Electronic valves are installed on the feed pipe, discharge pipe, vacuum pipe and compressed air pipe.

8. The device for removing small bubbles in optical fiber coating according to claim 1 or 2, characterized in that: The paint buffer tank is heated by a water bath.

9. A method for removing small bubbles in optical fiber coating using the device for removing small bubbles in optical fiber coating according to any one of claims 1 to 8, characterized in that: The steps include: S1. The paint in the paint storage tank is pumped into the paint buffer tank under the action of the booster pump. Since there is a large bubble detector in the pipeline behind the booster pump, when the large bubble detector alarms, the paint with bubbles will flow back to the paint storage tank through the paint return pipeline. When the large bubble detector stops alarming, the paint continues to flow forward into the paint buffer tank in the main pipeline. S2. After removing the bubbles in the coating buffer tank by heating and / or vacuuming, the coating cup is supplied with materials.

10. The method for removing small bubbles in optical fiber coating according to claim 9, characterized in that: Two groups of parallel paint buffer tanks are provided. When one group of paint buffer tanks is fed by a booster pump, the other group of paint buffer tanks supplies materials to the coating cups, and the two groups feed and supply materials alternately.

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