Optical fiber melt coating process method and device and optical fiber

Abstract

The invention discloses an optical fiber melt coating process method and device and an optical fiber. The method comprises the following steps: selecting a coated body; selecting a section of molten coating pipe; wherein the melting temperature of the melt coating pipe is lower than the melting temperature of the coated body; the coated body penetrates into the melt coating pipe, and the melt coating pipe and the coated body are fixed to one end of the melt coating pipe at the same time; the melt coating pipe is heated in a pipe type surrounding mode from the fixed end, the melt coating pipe at the heating position is made to melt and coat the coated body, the heating position is made to move towards the other end at a certain speed, and meanwhile the melt coating pipe penetrating through the coated body is stretched and fed at a certain speed; continuously melting the melt coating pipe, stretching and coating the melt coating pipe on the coated body to obtain a coated body; annealing is conducted; and cooling. According to the invention, the coated body is inserted into the melt coating pipe, and the melt coating pipe is heated in a tubular surrounding manner, so that the melt coating pipe is continuously melted and stretched to coat the coated body.

Description

Technical Field

[0001] The present invention relates to the technical field of optical fiber coating, and in particular to a process method, a device and an optical fiber for optical fiber melt coating. Background Art

[0002] In some applications, such as aerospace, defense, medical, construction and other fields, optical fiber sensing technology is often needed for precise measurement and monitoring. However, in extreme and harsh environments, bare optical fibers are easily broken and damaged, so they need to be coated with certain materials to increase their strength, toughness and service life. In this regard, designing a process method for optical fiber melt coating is conducive to the production of special optical fibers, and realizes the production of special material coatings for lightweight, flexible and customized optical fibers.

[0003] Patent No. CN103214181B designs a device and method for high-speed optical fiber drawing. The optical fiber is drawn by a heating mechanism, an annealing mechanism, a coating curing furnace, a cooling tube, a guide wheel, a wire collection tube and other mechanisms to achieve a certain diameter accuracy, stable warping and high coating quality. However, the design of this method is limited by the mechanism, and the process is relatively fixed. Patent No. CN116689238B designs an extrusion-type optical fiber coating system and a coating method thereof. The purpose of optical fiber coating with compact structure and short-time curing is achieved through a base, a clamp for limiting the position of the optical fiber, an optical fiber coating assembly and an automatic glue injection assembly for injecting glue into the optical fiber coating assembly. However, the design of this method is also limited by the mechanism and materials. In contrast, the process method of the present invention encompasses various processes of optical fiber melt coating, and each process supports customized requirements to achieve the purpose of optical fiber melt coating. Summary of the invention

[0004] The purpose of the present invention is to provide a process method, device and optical fiber for optical fiber melt coating, so as to solve the problem of limitations of existing optical fiber coating.

[0005] To solve the above problems, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a process for melt-coating an optical fiber, the method comprising: Select the coated object to be inserted into the melt coating tube; Selecting a section of melt-coated tube to be penetrated by the coated body; wherein the melting temperature of the melt-coated tube is lower than the melting temperature of the coated body; Inserting the coated body into the molten coating tube, and simultaneously fixing the molten coating tube and the coated body at one end; Starting from the fixed end, the melt-coated tube is heated in a tubular surrounding manner, so that the melt-coated tube at the heating position is melt-coated on the coated body, and the heating position is moved toward the other end at a certain speed, and at the same time, the melt-coated tube with the coated body is stretched and fed at a certain speed, so that the melt-coated tube is continuously melted and stretched and coated on the coated body, so as to obtain the coated body; wherein the heating temperature is the melting temperature of the melt-coated tube; annealing; cool down.

[0006] In the above scheme, the melt-coated tube and the coated object are fixed at the same time in the middle of the melt-coated tube through which the coated object is passed, and two heating members are used to move from the middle to both ends to heat the melt-coated tube.

[0007] In the above scheme, the melt-coated tube is first heated, and then the molten melt-coated tube is extruded onto the coated body so that the melt-coated tube is melted and stretched to be coated on the coated body; or the melt-coated tube is first extruded onto the coated body, and then the melt-coated tube is heated, so that the melt-coated tube is melted and stretched to be coated on the coated body.

[0008] In the above scheme, the coated body includes a composite transmission medium consisting of an optical fiber core or multiple optical fiber cores arranged in a certain manner or at least one optical fiber core arranged in a certain manner and at least one thin conductive metal wire.

[0009] In the above scheme, the material viscosity of the melt-coated tube is in the range of 100-1000 mPa·s at the melting temperature, and the melting temperature is in the range of 100-500°C.

[0010] In the above scheme, the material of the melt-coated tube includes polyetheretherketone, polyurethane, polyimide and metal nickel.

[0011] In the above scheme, the inner diameter of the melt-coated tube is 2 to 3 times that of the coated body, and the coated body and the melt-coated tube are kept vertical during the penetration process and the coating process.

[0012] In the above scheme, the diameter of the coated body is 0.125-0.25 mm, the inner diameter of the melt-coated tube is 0.25-0.5 mm, the outer diameter of the melt-coated tube is 1.5-3 mm, and the moving speed is 10-200 mm / min.

[0013] In a second aspect, the present invention provides an optical fiber melt coating device for implementing any one of the above optical fiber melt coating process methods, the device comprising a fixing fixture and a heating component; The fixing fixture is used for fixing the melt-coated tube and the coated object at the same time, and the heating component is used for heating the melt-coated tube in a tubular surrounding manner.

[0014] In a third aspect, the present invention further provides an optical fiber, which is produced by using any one of the optical fiber melt coating process methods described above.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects: The present invention selects a coated body and a molten coating tube, inserts the coated body into the molten coating tube, heats the molten coating tube in a tubular surrounding manner, and simultaneously stretches and feeds the molten coating tube with the coated body at a certain speed, so that the molten coating tube is continuously melted and stretched to coat the coated body, and finally obtains an optical fiber coating body with stable physical properties and light weight, thereby realizing optical fiber molten coating.

[0016] In addition, the coated body can be selected from multiple core materials for compounding, and arranged in a certain way to pass through the tube; there are many choices for the melt coating tube material, and the function can be diversified by doping and other methods to form special optical fibers such as optoelectronic composite optical fibers; the selection process of the above materials can reflect the flexible customization characteristics. The optical fiber coating body obtained by stretching has stable physical properties, and is lighter, smaller, and has a higher sensing density than multi-core optical cables and cables, and the coating method has a lower cost; special coating materials can adapt to special monitoring environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The present invention is a process flow chart of optical fiber melt coating; Figure 2 A schematic diagram of a process for melt coating of optical fiber; Figure 3 Schematic diagram of optical fiber melt coating. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0019] The present invention proposes a process method for melt coating of optical fiber, including selecting a coated body and a melt coating tube, arranging the coated body in position, inserting the coated body into the melt coating tube according to the arrangement, stretching and coating the melt coating tube material onto the coating body by heating, heat treatment, etc., and finally cooling to obtain a fiber coating body with stable physical properties and light weight. The process method encompasses various processes of melt coating of optical fiber, and each process supports customized requirements to achieve the purpose of melt coating of optical fiber. In view of the limitations of the mechanism and materials and the weight problem of multi-core optical cables, the present invention has the advantages of lighter weight, smaller volume, greater sensing density, lower coating cost, multi-core medium can be twisted to measure multi-dimensional parameters, and special coating materials can adapt to special monitoring environments compared with multi-core optical cables and electrical cables.

[0020] The process of optical fiber melt coating of the present invention is as follows: Figure 1 As shown, it includes: selecting the material of the coated body and arranging the position to be inserted into the molten coating tube; selecting a molten coating tube of a certain material with a certain inner and outer diameter to be inserted into the coated body; inserting the coated body into the molten coating tube in a specific arrangement, and fixing the molten coating tube and the coated body inside; heating a certain area of ​​the molten coating tube with the coated body in a tubular surrounding manner at a certain temperature, and moving in the opposite direction to the movement of the molten coating tube, and stretching and feeding the molten coating tube with the coated body at a certain speed to obtain a coated coated body with a certain diameter; annealing; cooling.

[0021] In some embodiments, one or more optical fiber cores or other composite core materials are inserted into the melt-coated tube, the coated body is inserted into the core body hole, and then the coated body is inserted into the melt-coated tube, so that a single-core is inserted into the melt-coated tube in a concentric manner and a multi-core coated body is inserted into the melt-coated tube in a specific arrangement; the melt-coated tube is kept vertical at all times during the insertion process.

[0022] In some embodiments, the coated body can be a small diameter optical fiber core and a thin conductive metal wire (iron wire or copper wire or nickel wire or other conductive metal wire) or other materials to form a composite transmission medium; wherein the multi-core medium can be twisted. The diameter of the coated body is about 0.125-0.25 mm per strand, and the inner diameter of the melt-coated tube is generally 2 to 3 times that of the coated body.

[0023] In some embodiments, the melt-coated tube should have a certain wall thickness and a certain ratio of outer diameter to inner diameter. The material of the melt-coated tube needs to have certain properties, including: a large ratio of outer diameter to inner diameter, the inner diameter is generally selected between 0.25 and 0.5 mm, and the outer diameter is generally selected between 1.5 and 3 mm; low cost; stable physical properties at room temperature to achieve a coating protection effect; during melt coating, the viscosity of the material is generally between 100 and 1000 mPa·s; the melting temperature is generally between 100 and 500°C; accordingly, the melt-coated tube materials that can be selected include polyetheretherketone or polyurethane or polyimide or metal nickel or other materials, and the above materials can also be doped, such as carbon nanotubes or gold palladium particles or other materials; the heating device can select a ceramic heating tube or a quartz heating tube or an electric heating tube or other heating tube for surround heating.

[0024] In some embodiments, the fixing may be a test clamp or other fixtures. During the stretching feeding, a motor-controlled winding roller or nozzle or other stretching feeding device may be used for stretching feeding, and the speed is generally 10-200 mm / min.

[0025] In some embodiments, common heat treatment methods include normalizing or annealing or other heat treatment methods. The purpose of annealing is to eliminate internal stress and increase material strength, toughness and service life. Cooling can be performed using a partition cooler, a spray cooler, a jacket cooler or other coolers.

[0026] The working principle of the present invention is: select a coated body and a molten coating tube, arrange the coated body in position, insert the coated body into the molten coating tube according to the arrangement, stretch and coat the molten coating tube material onto the coating body by heating, heat treatment, etc., and finally cool to obtain a fiber optic coating body with stable physical properties and light weight.

[0027] Example 1 The process method of optical fiber melt coating of this embodiment is as follows: Figure 1 and Figure 2 As shown, including: S1. Preparation process 1: Select the material of the object to be coated, arrange the position, and wait for it to be inserted into the melt coating tube; S2, preparation process 2: select a melt-coated tube of a certain material with a certain inner and outer diameter, and wait for the coated object to penetrate; S3, step 1: insert the coated object into the molten coating tube in a specific arrangement, and fix the molten coating tube and the coated object at the outlet end at the same time, such as Figure 3 As shown; S4, step 2: heating a certain area of ​​the molten coating tube with the coated body in a tubular surrounding manner at a certain temperature, and moving in the opposite direction of the movement of the molten coating tube, and stretching and feeding the molten coating tube with the coated body at a certain speed to obtain a coated body with a certain diameter; S5, step 3: annealing; S6, step 4: cooling.

[0028] When fixing, the coated object can be made to extend beyond the melt coating tube by a certain distance, or the melt coating tube can be made to extend beyond the coated object by a certain distance, or the ends of the two can be aligned, which can be set according to actual needs. However, when fixing, it is necessary to fix the melt coating tube and the coated object in the melt coating tube at the same time to serve as the starting point of melt coating.

[0029] The implementation principle is: select the coated body and the molten coating tube so that the optical fiber has the properties of different materials after coating; arrange the coated body in position and insert the coated body into the molten coating tube according to the arrangement, which is suitable for the center-to-center insertion of a single core and the fixed arrangement of multiple cores; stretch the molten coating tube material at a certain temperature and a certain speed and coat it on the coating body by heating, heat treatment and other methods, and keep the coated body and the molten coating tube vertical during the process to ensure that the obtained coating body has better quality; finally cool it to obtain a fiber optic coating body with stable physical properties and light weight.

[0030] Example 2 Different from the first embodiment, the present embodiment simultaneously fixes the molten coating tube and the coated body in the middle of the molten coating tube having the coated body, such as Figure 3 As shown, starting from the middle point, two heating components are used to move from the middle to both ends to heat the melt coating tube, which can save half of the melt coating time and greatly improve the efficiency of melt coating.

[0031] In addition, the melt-coated tube can be heated first, and then the molten melt-coated tube can be extruded onto the coated body so that the melt-coated tube is melt-coated on the coated body; or the melt-coated tube can be extruded onto the coated body first, and then the melt-coated tube can be heated so that the melt-coated tube is melt-coated on the coated body.

[0032] During melt coating, feeding can be achieved by pulling the coated object after coating, or by conveying the melt coating tube and the coated object. Since the melt coating tube will be stretched during melt coating, the melt coating tube and the coated object of the same length will exceed the coated object after melt coating, resulting in material waste; in order to save materials, the length of the melt coating tube can be made shorter than the coated object, and after melt coating, the length of the melt coating tube after melt coating is exactly equal to the coated object.

[0033] The present invention also provides an optical fiber melt coating device for implementing any of the optical fiber melt coating process methods described above, the device comprising a fixing fixture and a heating component; the fixing fixture is used to simultaneously fix the melt coating tube and the coated body, and the heating component is used to heat the melt coating tube in a tubular surrounding manner.

[0034] Finally, the present invention also provides an optical fiber, which is manufactured by using any one of the optical fiber melt coating process methods described above.

[0035] In summary, the present invention designs a process method for melt-coating optical fibers, and can realize the melt-coating process of special optical fibers by matching the coated body with a melt-coating tube material. The coated body can be selected from multiple core materials for composite, and arranged and passed through the tube in a certain way; there are multiple choices for the melt-coating tube material, and the functional diversification can be achieved through doping and other methods to form special optical fibers such as optoelectronic composite optical fibers; the selection process of the above materials can reflect flexible customization characteristics. The optical fiber coating body obtained by stretching has stable physical properties, and compared with multi-core optical cables and electrical cables, it is lighter in weight, smaller in size, has a higher sensing density, and has a lower coating cost; the special coating material can adapt to special monitoring environments.

[0036] It should be noted that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0037] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, and two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0038] It will be easily understood by those skilled in the art that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A process for melt coating of optical fiber, characterized in that: The method includes: Select the coated object to be inserted into the melt coating tube; Selecting a section of melt-coated tube to be penetrated by the coated body; wherein the melting temperature of the melt-coated tube is lower than the melting temperature of the coated body; Inserting the coated body into the molten coating tube, and simultaneously fixing the molten coating tube and the coated body at one end; Starting from the fixed end, the melt-coated tube is heated in a tubular surrounding manner, so that the melt-coated tube at the heating position is melt-coated on the coated body, and the heating position is moved toward the other end at a certain speed, and at the same time, the melt-coated tube with the coated body is stretched and fed at a certain speed, so that the melt-coated tube is continuously melted and stretched and coated on the coated body, so as to obtain the coated body; wherein the heating temperature is the melting temperature of the melt-coated tube; annealing; cool down.

2. The optical fiber melt coating process according to claim 1, characterized in that: The melt-coated tube and the object to be coated are fixed at the same time in the middle of the melt-coated tube through which the object to be coated is passed, and two heating members are used to move from the middle to both ends to heat the melt-coated tube.

3. The optical fiber melt coating process according to claim 1 or 2, characterized in that: The melt-coated tube is first heated, and then the molten melt-coated tube is extruded onto the coated body, so that the melt-coated tube is melted and stretched to coat the coated body; or the melt-coated tube is first extruded onto the coated body, and then the melt-coated tube is heated, so that the melt-coated tube is melted and stretched to coat the coated body.

4. The optical fiber melt coating process according to claim 1 or 2, characterized in that: The coated body includes a composite transmission medium consisting of an optical fiber core or a plurality of optical fiber cores arranged in a certain manner or at least one optical fiber core arranged in a certain manner and at least one thin conductive metal wire.

5. The optical fiber melt coating process according to claim 1 or 2, characterized in that: The viscosity of the material of the melt-coated tube at the melting temperature ranges from 100 to 1000 mPa·s, and the melting temperature ranges from 100 to 500°C.

6. The optical fiber melt coating process according to claim 5, characterized in that: Materials for melt-coated tubes include polyetheretherketone, polyurethane, polyimide, and metallic nickel.

7. The optical fiber melt coating process according to claim 1 or 2, characterized in that: The inner diameter of the melt-coated tube is 2 to 3 times that of the coated body, and the coated body and the melt-coated tube are kept vertical during the penetration process and the coating process.

8. The optical fiber melt coating process according to claim 1 or 2, characterized in that: The diameter of the coated body is 0.125~0.25mm, the inner diameter of the melt-coated tube is 0.25~0.5mm, the outer diameter of the melt-coated tube is 1.5~3mm, and the moving speed is 10~200mm / min.

9. An optical fiber melt coating device for implementing the optical fiber melt coating process method according to any one of claims 1 to 8, characterized in that: The device includes a fixing fixture and a heating component; The fixing fixture is used for fixing the melt-coated tube and the coated object at the same time, and the heating component is used for heating the melt-coated tube in a tubular surrounding manner.

10. An optical fiber, characterized in that: The optical fiber is manufactured by the optical fiber melt coating process described in any one of claims 1 to 8.

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