CN113620592A - Optical fiber drawing equipment and optical fiber drawing method - Google Patents
Optical fiber drawing equipment and optical fiber drawing method Download PDFInfo
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- CN113620592A CN113620592A CN202010371255.4A CN202010371255A CN113620592A CN 113620592 A CN113620592 A CN 113620592A CN 202010371255 A CN202010371255 A CN 202010371255A CN 113620592 A CN113620592 A CN 113620592A
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- 238000012681 fiber drawing Methods 0.000 title claims abstract description 62
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/10—Non-chemical treatment
- C03B37/12—Non-chemical treatment of fibres or filaments during winding up
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/02—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor
- C03B37/025—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor from reheated softened tubes, rods, fibres or filaments, e.g. drawing fibres from preforms
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/02—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor
- C03B37/025—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor from reheated softened tubes, rods, fibres or filaments, e.g. drawing fibres from preforms
- C03B37/0253—Controlling or regulating
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/01—Manufacture of glass fibres or filaments
- C03B37/02—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor
- C03B37/025—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor from reheated softened tubes, rods, fibres or filaments, e.g. drawing fibres from preforms
- C03B37/027—Fibres composed of different sorts of glass, e.g. glass optical fibres
- C03B37/02763—Fibres having axial variations, e.g. axially varying diameter, material or optical properties
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
- C03B37/10—Non-chemical treatment
- C03B37/14—Re-forming fibres or filaments, i.e. changing their shape
- C03B37/15—Re-forming fibres or filaments, i.e. changing their shape with heat application, e.g. for making optical fibres
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C25/00—Surface treatment of fibres or filaments made from glass, minerals or slags
- C03C25/10—Coating
- C03C25/12—General methods of coating; Devices therefor
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
Abstract
The application is applicable to the technical field of optical fiber preparation, and provides optical fiber drawing equipment and an optical fiber drawing method, wherein the optical fiber drawing equipment comprises a feeding device, a tapering device, a control console and a heating device arranged between the feeding device and the tapering device; the feeding device comprises a first motor and a first driving wheel driven by the first motor, the cone drawing device comprises a second motor and a second driving wheel driven by the second motor, and the console is used for controlling the rotating speed of the first motor, the rotating speed of the second motor and the heating power of the heating device. The optical fiber is stretched under the controllable temperature condition, the stretching rate is directly controlled by the rotating speed difference of the first driving wheel and the second driving wheel, and further the optical fiber with a specific shape, such as a long tapered optical fiber, a fusiform optical fiber or a calabash-shaped optical fiber, can be drawn according to actual needs; because the optical fiber is quantitatively heated and quantitatively stretched under the controllable condition, the optical fiber can be prevented from being broken in the drawing process, and the limit length of the drawn and molded optical fiber is improved.
Description
Technical Field
The present disclosure relates to the field of optical fiber manufacturing technologies, and in particular, to an optical fiber drawing apparatus and an optical fiber drawing method.
Background
The high-power all-fiber large pulse energy (femtosecond, picosecond and nanosecond) laser has wide application in the fields of precision micromachining, biomedical treatment, scientific research and the like by virtue of the characteristics of narrow pulse width, large single pulse energy, high repetition frequency and the like. Compared with solid lasers and titanium gem lasers, the ultrashort pulse laser realized by adopting the all-fiber laser scheme has the advantages of low cost, simple structure, high efficiency, good stability and the like, and is more favorable for large-scale industrial application.
Limited by the nonlinear effect (stimulated raman scattering effect) in the optical fiber, in order to obtain a high-power large-pulse-energy all-fiber laser, the method adopted in the conventional scheme is to adopt a large-core-diameter common active optical fiber as a gain medium in the main amplification stage of the laser and perform power amplification in a cladding pumping manner. That is, the high-power narrow-wavelength pump light is pumped into the cladding of the common active fiber through the fiber combiner, and the pump light is refracted in the fiber cladding and passes through the fiber core, so that the long-wavelength signal light transmitted in the fiber core absorbs energy, and the power amplification is obtained.
In order to obtain a fiber laser with higher power, a laser amplifier in the conventional scheme adopts a large-core-diameter common active fiber, and the normalized frequency of a fiber core of the laser amplifier is often far greater than that of a single-mode condition of optical transmission (the normalized frequency is less than or equal to 2.405), so that the quality of an output light spot of the laser is poor, and the application of the high-power fiber laser is limited. Even if a mode field adapter is adopted to partially improve the quality of an output beam, the stability of the quality of a laser beam is greatly tested under the influence of factors such as vibration, fiber bending and the like.
In some versions, the laser amplifier employs a tapered fiber. The existing technical schemes for preparing the tapered optical fiber can be generally divided into two types: one is that the two ends of the optical fiber are clamped by a fixing clamp, the middle of the optical fiber is heated and then the optical fiber is stretched to two sides to form a tapered optical fiber, the length of the drawn optical fiber is limited by factors such as a mechanical device, the length of the optical fiber does not exceed 10cm, and the shape of the drawn tapered optical fiber is difficult to control; and secondly, the tapered optical fiber is drawn by controlling the traction telescopic rod on the fused optical fiber preform, the optical fiber is easy to be broken in the scheme of drawing the optical fiber by gravity, and the drawing process of the optical fiber is easy to be interfered by air flow, so that the quality and the limit length of the tapered optical fiber are seriously influenced.
Disclosure of Invention
The application aims to provide optical fiber drawing equipment and aims to solve the technical problem that the controllability of the traditional optical fiber drawing equipment to an optical fiber drawing process is poor.
The optical fiber drawing equipment comprises a feeding device, a tapering device, a control console and a heating device, wherein the heating device is arranged between the feeding device and the tapering device; the feeding device comprises a first motor and a first driving wheel driven by the first motor, the cone-drawing device comprises a second motor and a second driving wheel driven by the second motor, and the control console is used for controlling the rotating speed of the first motor, the rotating speed of the second motor and the heating power of the heating device.
In one embodiment of the present application, the optical fiber drawing apparatus further comprises a fiber coiling device disposed opposite to the tapering device, the fiber coiling device comprises a third motor and a fiber coiling wheel driven by the third motor, and the console is further configured to control a rotation speed of the third motor.
In one embodiment of the present application, the rotational speeds of the first motor, the second motor, and the third motor satisfy: the fiber coiling wheel and the second driving wheel rotate at the same speed, and the first driving wheel and the second driving wheel rotate at different speeds.
In an embodiment of the present application, the optical fiber drawing apparatus further includes a glue spreading device disposed between the tapered device and the fiber coiling device, and the glue spreading device includes a glue spreader and a curing machine disposed between the glue spreader and the fiber coiling device.
In one embodiment of the present application, the optical fiber drawing apparatus further comprises a monitoring device disposed between the heating device and the glue coating device, the monitoring device being configured to monitor a diameter of the optical fiber after being drawn by the feeding device and the tapering device.
In one embodiment of the present application, the first capstan is provided with a first fiber groove, the first fiber groove being disposed around the first capstan; the feeding device comprises a first driven wheel arranged opposite to the first driving wheel, the axis of the first driven wheel is parallel to that of the first driving wheel, and the first driven wheel is tangent to the first driving wheel. The second driving wheel is provided with a second optical fiber groove, the second optical fiber groove surrounds the second driving wheel, the tapering device comprises a second driven wheel opposite to the second driving wheel, the axis of the second driven wheel is parallel to the axis of the second driving wheel, and the second driven wheel is tangent to the second driving wheel.
In one embodiment of the present application, the optical fiber drawing apparatus further comprises a work bench for mounting the feeding device, the heating device and the tapering device; the feeding device further comprises a first support, and the first motor is connected with the workbench through the first support; the cone drawing device further comprises a second support, and the second motor is connected with the workbench through the second support.
In one embodiment of the present application, the heating device includes a fiber guide provided with a third fiber groove, and a heat source disposed opposite the third fiber groove.
It is a further object of the present application to provide an optical fiber drawing method suitable for use in an optical fiber drawing apparatus as described above, comprising the steps of:
winding an optical fiber: the optical fiber is simultaneously attached to the first driving wheel and the second driving wheel, and the console controls the first driving wheel and/or the second driving wheel to rotate until the optical fiber is straightened;
drawing an optical fiber: the console controls the heating device to heat the optical fiber, and the console controls the first driving wheel and the second driving wheel to rotate at a different speed so as to draw the optical fiber.
In an embodiment of the present application, after the step of drawing the optical fiber, the method further comprises:
coating a glue layer: the console controls the glue spreader to coat a protective glue layer on the drawn and molded optical fiber, and the console controls the curing machine to cure the protective glue layer coated outside the optical fiber;
coiling fiber: the console controls the fiber coiling wheel and the second driving wheel to rotate at the same speed, so that the optical fibers coated with the protective glue layer are wound on the fiber coiling wheel.
The optical fiber drawing equipment at least has the following beneficial effects:
when the optical fiber drawing equipment provided by the application draws the optical fiber, the console controls the first motor and the second motor to respectively drive the first driving wheel and the second driving wheel to rotate in a differential mode, the heating device is controlled to heat the optical fiber to soften the optical fiber, the optical fiber which is just opposite to the heating device is drawn under the action of the differential rotation of the first driving wheel and the second driving wheel, the optical fiber can be drawn under the controllable temperature condition through the scheme, the drawing rate is directly controlled by the rotation speed difference of the first driving wheel and the second driving wheel, and the optical fiber with a specific shape, such as a long conical optical fiber, a fusiform optical fiber or a calabash optical fiber, can be drawn according to actual needs; because the optical fiber is quantitatively heated and quantitatively stretched under the controllable condition, the optical fiber can be prevented from being broken in the drawing process, and the limit length of the drawn and molded optical fiber is improved.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a schematic structural diagram of an optical fiber drawing apparatus according to an embodiment of the present application;
FIG. 2 is an enlarged view of a portion of FIG. 1 at A;
FIG. 3 is an enlarged view of a portion of FIG. 1 at B;
FIG. 4 is a schematic structural diagram of a feeding device provided in an embodiment of the present application;
FIG. 5 is a schematic mechanism diagram of a tapering device provided in an embodiment of the present application;
FIG. 6 is a schematic diagram illustrating the operation of an optical fiber drawing apparatus according to an embodiment of the present invention;
FIG. 7 is a schematic flow chart of a fiber drawing method provided in an embodiment of the present application;
FIG. 8 is a schematic view showing a change in diameter of an optical fiber drawn by an optical fiber drawing apparatus according to an embodiment of the present invention;
fig. 9 is a schematic diagram of a rough short-circuit light-emitting mode when a reverse pump is used to introduce signal light into an optical fiber drawn by an optical fiber drawing apparatus according to an embodiment of the present application.
Reference numerals referred to in the above figures are detailed below:
1-a feeding device; 11-a first electric machine; 12-a first capstan; 121-a first fiber groove; 13-a first driven wheel; 14-a first scaffold; 2-a heating device; 21-a heat source; 22-a fiber guide; 221-a third fiber groove; 3-a tapering device; 31-a second motor; 32-a second drive wheel; 321-a second fiber groove; 33-a second driven wheel; 34-a second bracket; 4-a console; 5-a fiber coiling device; 51-a third motor; 52-fiber coiling wheel; 53-third scaffold; 6-a gluing device; 61-a glue spreader; 62-a curing machine; 7-a monitoring device; 71-CCD camera; 72-a fourth scaffold; 8-an optical fiber; 9-a workbench.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly or indirectly secured to the other element. When an element is referred to as being "connected to" another element, it can be directly or indirectly connected to the other element. The terms "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positions based on the orientations or positions shown in the drawings, and are for convenience of description only and not to be construed as limiting the technical solution. The terms "first", "second" and "first" are used merely for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features. The meaning of "plurality" is two or more unless specifically limited otherwise.
In order to explain the technical solutions of the present application, the following detailed descriptions are made with reference to specific drawings and examples.
Referring to fig. 1, 4 and 5, an embodiment of the present application provides an optical fiber drawing apparatus, which includes a feeding device 1, a tapering device 3, a console 4, and a heating device 2 disposed between the feeding device 1 and the tapering device 3; the feeding device 1 comprises a first motor 11 and a first driving wheel 12 driven by the first motor 11, the tapering device 3 comprises a second motor 31 and a second driving wheel 32 driven by the second motor 31, and the console 4 is used for controlling the rotating speed of the first motor 11, the rotating speed of the second motor 31 and the heating power of the heating device 2.
Specifically, the optical fiber drawing apparatus provided in the present embodiment operates as follows:
referring to fig. 6, the optical fiber 8 to be drawn is simultaneously attached to the first driving wheel 12 and the second driving wheel 32, and the first driving wheel 12 and/or the second driving wheel 32 are/is manually rotated, or the console 4 controls the first driving wheel 12 and/or the second driving wheel 32 to rotate until the optical fiber 8 is straightened; then, the console 4 controls the heating device 2 to increase the heating power, so that a portion of the optical fiber 8 is heated and softened, and the console 4 controls the first driving wheel 12 and the second driving wheel 32 to rotate at different speeds, specifically, the rotating speed of the first driving wheel 12 is less than or equal to the rotating speed of the second driving wheel 32, and the optical fiber 8 moves along the direction of the first driving wheel 12 pointing to the second driving wheel 32 under the driving of the first driving wheel 12 and the second driving wheel 32. Thus, since there is a difference in the rotational speed between the first capstan 12 and the second capstan 32 and the optical fiber 8 is tightly attached to both the first capstan 12 and the second capstan 32 under the influence of the frictional force, a section of the optical fiber 8 heated by the heating means 2 is softened and becomes longer and thinner under the action of the tensile force; the degree of the optical fiber 8 being stretched can be controlled by controlling the difference in the rotational speed of the first capstan 12 and the second capstan 32, thereby achieving controlled drawing of the optical fiber 8.
The optical fiber drawing equipment provided by the embodiment can at least achieve the following beneficial technical effects:
when the optical fiber 8 is drawn by the optical fiber drawing apparatus provided in this embodiment, the console 4 controls the first motor 11 and the second motor 31 to respectively drive the first driving wheel 12 and the second driving wheel 32 to rotate at a differential speed, and simultaneously controls the heating device 2 to heat the optical fiber 8 to soften the optical fiber, and the optical fiber 8 facing the heating device 2 is drawn under the differential rotation action of the first driving wheel 12 and the second driving wheel 32, such a scheme can enable the optical fiber 8 to be drawn under a controllable temperature condition, and simultaneously the drawing rate is directly controlled by the rotation speed difference of the first driving wheel 12 and the second driving wheel 32, so that the optical fiber 8 with a specific shape, such as a long tapered optical fiber, a shuttle-shaped optical fiber or a gourd-shaped optical fiber, can be drawn according to actual needs; since the optical fiber 8 is quantitatively heated and quantitatively stretched under a controllable condition, the optical fiber 8 can be prevented from being broken in the drawing process, and the limit length of the drawn and molded optical fiber 8 is increased.
Referring to fig. 8, the optical fiber drawing apparatus provided in this embodiment can effectively draw an optical fiber 8 having a cladding diameter in the range of 80 to 1000 μm, and produce a tapered optical fiber having a length of 0.1 to 5 m. In some embodiments, the fiber 8 can be drawn to the order of 10m without breaking. In some embodiments, a 1.6M long tapered fiber is drawn using the fiber drawing apparatus described above, the fiber 8 having a larger end with an exit spot M2The value can reach within 1.3, the ellipticity reaches above 0.95, the error range of the diameter of the optical fiber 8 is within 5 microns, the diameter of the optical fiber 8 is in smooth transition, no burrs are formed on the surface of the optical fiber 8, and the performance requirements of the optical fiber 8 amplifier on the tapered optical fiber can be completely met.
The optical fiber drawing apparatus provided by the embodiment can draw a long tapered optical fiber suitable for application to a laser amplifier.
Referring to fig. 9, the long tapered active fiber 8 has a very thin taper shape due to the core diameter and the cladding diameter, and when the pump light is incident from the thick end of the tapered fiber, the reflection frequency and the transmission frequency of the pump light in the fiber 8 can be greatly increased, so as to increase the utilization rate of the rare earth ions doped in the long tapered fiber, and further obtain the same laser power amplification factor with the length of one third of the common fiber 8. Furthermore, the long tapered optical fiber drawn by the optical fiber drawing equipment provided by the embodiment has the advantages of good light beam quality and being not easily affected by factors such as external vibration and bending of the optical fiber 8. Specifically, when signal light is transmitted in the fiber core of the ordinary large-mode-area optical fiber 8, because the core diameter is large, light beams are transmitted in a back-and-forth total reflection mode in the core diameter, vibration and bending can affect the signal light transmitted in the fiber core in a reflection mode, light spots of the signal light are deteriorated, a high-order mode is generated, and the shape of an output light spot of the signal light is changed from a pure circular Gaussian light spot into an ellipse or even a plurality of light spots.
When the long tapered optical fiber manufactured by the optical fiber drawing apparatus provided in this embodiment transmits signal light, the normalized frequency of the long tapered optical fiber can be controlled below 2.4 due to the small core diameter of the thin end of the long tapered optical fiber. The long tapered optical fiber adopts a reverse pumping scheme of small-end signal light injection, pump light is input from a thick end, signal light is input from a thin end, and then the single-mode state of the signal light in a core diameter area can be still kept at a position which is several meters away from the thin end, the influence of vibration and bending is small, and the output light spot quality is good. The laser amplifier of the long tapered optical fiber manufactured by the optical fiber drawing device provided by the embodiment reduces the amplification saturation power under the same pumping power, that is, the power of the signal light with the amplification gain reaching saturation from the watt level to the milliwatt level, and reduces the requirement of the power of the signal light at the front end pre-amplification level because the tapered optical fiber has high absorption efficiency on the pumping light, large amplification factor and low requirement on the power of the signal light.
Referring to fig. 1 and 6, in an embodiment of the present application, the fiber drawing apparatus further includes a fiber winding device 5 disposed opposite to the tapering device 3, the fiber winding device 5 includes a third motor 51 and a fiber winding wheel 52 driven by the third motor 51, and the console 4 is further configured to control a rotation speed of the third motor 51. Specifically, the console 4 controls the third motor 51 to rotate, so as to drive the fiber winding wheel 52 to rotate, so that the drawn optical fiber 8 can be continuously wound on the fiber winding wheel 52, thereby preventing the optical fiber 8 from being broken during the drawing process.
As a specific solution of this embodiment, the diameter of the fiber winding wheel 52 is greater than or equal to 20cm and less than or equal to 80cm, such an arrangement may enable the optical fiber 8 to be wound on the fiber winding wheel 52 with a sufficiently large curvature radius, so as to avoid the optical fiber 8 from being broken by force during the drawing process, and at the same time, the fiber winding wheel 52 does not occupy too much space volume, which is beneficial to the miniaturization of the optical fiber drawing apparatus.
In one embodiment of the present application, the rotational speeds of the first motor 11, the second motor 31, and the third motor 51 satisfy: the first driving wheel 12 and the second driving wheel 32 rotate at the same speed, and the second driving wheel 32 and the fiber coiling wheel 52 rotate at different speeds. The fiber coiling wheel 52 and the second driving wheel 32 rotate at the same speed to ensure that the drawn optical fiber 8 can be uniformly wound on the fiber coiling wheel 52, so that the optical fiber 8 is prevented from being broken in the drawing process, and the first driving wheel 12 and the second driving wheel 32 rotate at different speeds to draw part of the optical fiber 8 of the heating device 2. Specifically, the rotational speed of the first drive pulley 12 is less than or equal to the rotational speed of the second drive pulley 32.
It should be understood that, in the present embodiment, the fiber winding wheel 52 and the second driving wheel 32 rotate at the same speed, and the differential rotation of the first driving wheel 12 and the second driving wheel 32 means that, under the driving of the first motor 11, the second motor 31 and the third motor 51, the fiber winding wheel 52 and the second driving wheel 32 rotate at the same linear speed, and the first driving wheel 12 and the second driving wheel 32 rotate synchronously at a certain linear speed difference. The respective descriptions of the rotational speeds of the first capstan 12, the second capstan 32 and the fiber winding wheel 52 throughout this application refer to the linear speeds of the first capstan 12, the second capstan 32 and the fiber winding wheel 52.
Referring to fig. 1, 3 and 6, in an embodiment of the present application, the optical fiber drawing apparatus further includes a glue applicator 6 disposed between the tapering device 3 and the fiber coiling device 5, and the glue applicator 6 includes a glue applicator 61 and a curing machine 62 disposed between the glue applicator 61 and the fiber coiling device 5. The drawn optical fiber 8 passes through the glue spreader 61, the protective glue layer is uniformly coated on the glue spreader 61, and then the protective glue layer is cured at the curing machine 62, so that a protective glue layer capable of preventing the optical fiber 8 from being broken is formed outside the optical fiber 8.
As a specific aspect of this embodiment, the coating machine 61 is a tubular coating machine 61 to uniformly coat the protective coating on the outer surface of the optical fiber 8 after drawing. As a specific scheme of this embodiment, the curing machine 62 includes an ultraviolet light source, and the ultraviolet light source is used as a light source of the curing device for protecting the adhesive layer, so that the lamp has the characteristics of long service life, small heat productivity and high energy utilization rate, and has excellent curing efficiency and curing uniformity; more preferably, the ultraviolet light source may include a plurality of ultraviolet lamps uniformly disposed around the optical fiber 8, and the power of the plurality of ultraviolet lamps is greater than or equal to 600w in combination, so as to further improve the uniformity and efficiency of curing the protective adhesive layer.
As a specific solution of this embodiment, before the optical fiber 8 is drawn, the protective glue layer needs to be stripped off first; or, the fiber drawing equipment directly stretches the fiber core without the protective layer, and then coats and cures the protective glue layer.
Referring to fig. 1, 2 and 6, in one embodiment of the present application, the optical fiber drawing apparatus further includes a monitoring device 7 disposed between the heating device 2 and the glue applying device 6, wherein the monitoring device 7 is used for monitoring the diameter of the optical fiber 8 after being drawn by the feeding device 1 and the tapering device 3. The purpose of the monitoring device 7 is to analyze and process data such as diameter and length changes of the optical fiber 8, and to give a warning in case of an abnormal working condition of the optical fiber drawing apparatus, such as a break of the optical fiber 8.
As a specific solution of this embodiment, the monitoring device 7 is disposed between the heating device 2 and the tapering device 3, the monitoring device 7 specifically includes a CCD camera 71 disposed opposite to the drawn optical fiber 8, the CCD camera 71 collects an image of the drawn tapered optical fiber in the whole drawing process, and the console 4 determines the diameter of the drawn optical fiber 8 according to the image collected by the CCD camera 71, so as to generate data such as the diameter and length change of the optical fiber 8.
Referring to fig. 4, in an embodiment of the present application, the first capstan 12 is provided with a first fiber groove 121 for clamping the fiber 8, and the first fiber groove 121 is disposed around the first capstan 12; the feeding device 1 comprises a first driven wheel 13 arranged opposite to the first driving wheel 12, the axis of the first driven wheel 13 is parallel to the axis of the first driving wheel 12, and the first driven wheel 13 is tangent to the first driving wheel 12.
The first fiber groove 121 is provided to enable the optical fiber 8 to be attached to the surface of the first capstan 12 along the first fiber groove 121, specifically, the diameter of the first fiber groove 121 is smaller than the diameter of the optical fiber 8, and the first fiber groove 121 applies a clamping force and a friction force to the optical fiber 8 to clamp the optical fiber 8 so as to prevent the optical fiber 8 from deviating from the position of heating and drawing; meanwhile, the first driven wheel 13 tangent to the first driving wheel 12 is arranged, so that the optical fiber 8 can be further prevented from deviating from the normal position, the friction force between the optical fiber 8 and the first driving wheel 12 can be improved, and the optical fiber 8 is prevented from slipping in the heating and drawing process.
Referring to fig. 5, in an embodiment of the present application, the second driving pulley 32 is provided with a second fiber groove 321 for clamping the optical fiber 8, the second fiber groove 321 is disposed around the second driving pulley 32, the tapering device 3 includes a second driven pulley 33 disposed opposite to the second driving pulley 32, an axis of the second driven pulley 33 is parallel to an axis of the second driving pulley 32, and the second driven pulley 33 is tangent to the second driving pulley 32.
The second fiber groove 321 is provided to enable the optical fiber 8 to be attached to the surface of the second capstan 32 along the second fiber groove 321, specifically, the diameter of the second fiber groove 321 is smaller than the diameter of the optical fiber 8, and the second fiber groove 321 applies a clamping force and a friction force to the optical fiber 8 to clamp the optical fiber 8 so as to prevent the optical fiber 8 from deviating from the position of heating and drawing; meanwhile, the second driven wheel 33 tangent to the second driving wheel 32 is arranged, so that the optical fiber 8 can be further prevented from deviating from the normal position, the friction force between the optical fiber 8 and the second driving wheel 32 can be improved, and the optical fiber 8 is prevented from slipping in the heating and drawing process.
In one embodiment of the present application, the optical fiber drawing apparatus further comprises a table 9 for mounting the feeding device 1, the heating device 2 and the tapering device 3; the feeding device 1 further comprises a first bracket 14, and the first motor 11 is connected with the workbench 9 through the first bracket 14; the cone drawing device 3 further comprises a second bracket 34, and the second motor 31 is connected with the workbench 9 through the second bracket 34.
As a specific scheme of this embodiment, the fiber coiling device 5 further includes a third bracket 53 for mounting the fiber coiling wheel 52 and the first motor 51, and the third bracket 53 is disposed on a side of the tapering device 3 away from the feeding device 1; the monitoring device 7 further comprises a fourth bracket 72 for mounting the CCD camera 71 on the table 9.
As a specific solution of this embodiment, the first driven wheel 13 is disposed closely to the first driving wheel 12, and more specifically, the first driven wheel 13 may be disposed on a first guide rail, the first guide rail is disposed along a direction in which the first driven wheel 13 is far away from the first driving wheel 12, and one end of the first guide rail far away from the first driven wheel 13 is provided with a first clamping block, the first driven wheel is connected with the first bracket 14 through a first connecting block, and the spring is abutted against the first clamping block and the first connecting block at the same time, so that the first driving wheel 12 can be closely attached to the first driven wheel 13 to provide sufficient clamping force and friction force for the optical fiber 8; the second is followed driving wheel 33 and is hugged closely the setting of second driving wheel 32, and is more specific, second is followed driving wheel 33 and can be set up on the second guide rail, the second guide rail is followed the direction setting that second driving wheel 32 was kept away from to second driving wheel 33 along the second, and the second guide rail is kept away from the second and is provided with the second fixture block from two ends of driving wheel 33, the second is followed driving wheel and is passed through the second connecting block and be connected with second support 34, the spring is butt second fixture block and second connecting block simultaneously, like this, second driving wheel 32 can be followed driving wheel 33 with the second and closely laminated, provide sufficient clamping-force and frictional force to optic fibre 8.
Referring to fig. 2, in one embodiment of the present application, the heating device 2 includes a fiber 8 guide 22 having a third fiber groove 221, and a heat source 21 disposed opposite to the third fiber groove 221. The third fiber groove 221 is provided for the purpose of allowing the optical fiber 8 to be disposed on the surface of the guide rail 22 of the optical fiber 8 along the third fiber groove 221, and catching the optical fiber 8 to prevent the optical fiber 8 from deviating from the correct position for heating drawing.
As a specific scheme of this embodiment, the heat source 21 is an oxyhydrogen flame heat source 21, and more specifically, the oxyhydrogen flame heat source 21 includes an air-feeding fire head pipe, a gas flow device, and a hydrogen source and an oxygen source connected to the air-feeding fire head pipe, and the console 4 can control the flow rates of the hydrogen and the oxygen simultaneously, so as to change the flame temperature and the heating range during the tapering process of the optical fiber 8; in this embodiment the guide rails 22 of the fibre 8 are made of a fire-retardant material. Or, the heat source 21 is a laser heat source 21, such as a carbon dioxide laser heat source 21, the laser heat source 21 includes a laser generator and a laser waveguide connected to the laser generator and facing the third optical fiber groove 221, and the console 4 controls the power of the laser generator and the size of the light spot generated by the laser waveguide, so as to control the flame temperature and the heating range during the tapering process of the optical fiber 8.
More specifically, the heating device 2 further comprises an energy source assembly, which may be arranged inside the work table 9. For the scheme of adopting the oxyhydrogen flame heat source 21, a hydrogen cylinder and an oxygen cylinder can be arranged in the workbench, and the hydrogen cylinder and the oxygen cylinder are respectively connected with an air supply fire head pipe through corresponding conduits; for the solution using the laser heat source 21, a laser generator may be provided inside the stage, and the laser alignment fiber 8 is irradiated through a laser waveguide.
Referring to fig. 7, an embodiment of the present application provides an optical fiber drawing method suitable for the optical fiber drawing apparatus as described above, specifically, the optical fiber drawing method includes the following steps:
s1, winding an optical fiber: the optical fiber 8 is simultaneously attached to the first driving wheel 12 and the second driving wheel 32, and the console 4 controls the first driving wheel 12 and/or the second driving wheel 32 to rotate until the optical fiber 8 is straightened;
s2 drawing the optical fiber: the console 4 controls the heating device 2 to heat the optical fiber 8, and the console 4 controls the first driving pulley 12 and the second driving pulley 32 to rotate at different speeds so as to draw the optical fiber 8.
The implementation of the optical fiber drawing method provided by the embodiment can at least achieve the following beneficial technical effects:
the console 4 controls the first motor 11 and the second motor 31 to respectively drive the first driving wheel 12 and the second driving wheel 32 to rotate in a differential speed manner, and controls the heating device 2 to heat the optical fiber 8 to soften the optical fiber, and the optical fiber 8 facing the heating device 2 is stretched under the differential speed rotation action of the first driving wheel 12 and the second driving wheel 32, so that the optical fiber 8 can be stretched under a controllable temperature condition, and meanwhile, the stretching rate is directly controlled by the rotation speed difference of the first driving wheel 12 and the second driving wheel 32, and further, the optical fiber 8 with a specific shape, such as a long tapered optical fiber, a fusiform optical fiber or a calabash optical fiber, can be drawn according to actual needs; since the optical fiber 8 is quantitatively heated and quantitatively stretched under a controllable condition, the optical fiber 8 can be prevented from being broken in the drawing process, and the limit length of the drawn and molded optical fiber 8 is increased.
Referring to fig. 7, in an embodiment of the present application, after the step of drawing the optical fiber 8, the method further includes:
s3, coating a glue layer: the console 4 controls the glue spreader 61 to coat the protective glue layer on the drawn and molded optical fiber 8, and the console 4 controls the curing machine 62 to cure the protective glue layer coated outside the optical fiber 8;
s4, coiling fiber: the console 4 controls the fiber reel 52 to rotate at the same speed as the second driving wheel 32, so that the optical fiber 8 coated with the protective adhesive layer is wound around the fiber reel 52.
The drawn optical fiber 8 passes through a glue spreader 61, a protective glue layer is uniformly coated on the glue spreader 61, then the protective glue layer is cured at a curing machine 62, and a protective glue layer capable of preventing the optical fiber 8 from being broken is formed outside the optical fiber 8; the console 4 controls the third motor 51 to rotate, so as to drive the fiber winding wheel 52 to rotate, so that the drawn optical fiber 8 can be continuously wound on the fiber winding wheel 52, thereby preventing the optical fiber 8 from being broken during the drawing process.
The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims (10)
1. An optical fiber drawing device is characterized by comprising a feeding device, a tapering device, a control console and a heating device arranged between the feeding device and the tapering device; the feeding device comprises a first motor and a first driving wheel driven by the first motor, the cone-drawing device comprises a second motor and a second driving wheel driven by the second motor, and the control console is used for controlling the rotating speed of the first motor, the rotating speed of the second motor and the heating power of the heating device.
2. The optical fiber drawing apparatus as claimed in claim 1, wherein the optical fiber drawing apparatus further comprises a fiber coiling device disposed opposite the tapering device, the fiber coiling device comprising a third motor and a fiber coiling wheel driven by the third motor, the console further being configured to control a rotational speed of the third motor.
3. The fiber drawing apparatus of claim 2, wherein the rotational speeds of the first motor, the second motor, and the third motor are such that: the fiber coiling wheel and the second driving wheel rotate at the same speed, and the first driving wheel and the second driving wheel rotate at different speeds.
4. The optical fiber drawing apparatus as claimed in claim 2, further comprising a glue spreading device disposed between the taper device and the fiber coiling device, the glue spreading device comprising a glue spreader and a curing machine disposed between the glue spreader and the fiber coiling device.
5. The optical fiber drawing apparatus as claimed in claim 4, further comprising a monitoring device disposed between the heating device and the glue spreading device for monitoring a diameter of the optical fiber after being drawn by the feeding device and the tapering device.
6. The optical fiber drawing apparatus as claimed in any one of claims 1 to 5, wherein said first capstan is provided with a first fiber groove, said first fiber groove being disposed around said first capstan; the feeding device further comprises a first driven wheel arranged opposite to the first driving wheel, the axis of the first driven wheel is parallel to the axis of the first driving wheel, and the first driven wheel is tangent to the first driving wheel; the second driving wheel is provided with a second optical fiber groove, the second optical fiber groove surrounds the second driving wheel, the tapering device further comprises a second driven wheel opposite to the second driving wheel, the axis of the second driven wheel is parallel to the axis of the second driving wheel, and the second driven wheel is tangent to the second driving wheel.
7. The optical fiber drawing apparatus as claimed in any one of claims 1 to 5, wherein the optical fiber drawing apparatus further comprises a table for mounting the feeding device, the heating device and the tapering device; the feeding device further comprises a first support, and the first motor is connected with the workbench through the first support; the cone drawing device further comprises a second support, and the second motor is connected with the workbench through the second support.
8. The optical fiber drawing apparatus as claimed in any one of claims 1 to 5, wherein the heating device includes a fiber guide provided with a third fiber groove, and a heat source disposed opposite to the third fiber groove.
9. An optical fiber drawing method, characterized in that the optical fiber drawing method is applied to the optical fiber drawing apparatus according to any one of claims 1 to 8, the optical fiber drawing method comprising the steps of:
winding an optical fiber: the optical fiber is simultaneously attached to the first driving wheel and the second driving wheel, and the console controls the first driving wheel and/or the second driving wheel to rotate until the optical fiber is straightened;
drawing an optical fiber: the console controls the heating device to heat the optical fiber, and the console controls the first driving wheel and the second driving wheel to rotate at a different speed so as to draw the optical fiber.
10. The optical fiber drawing method as claimed in claim 9, further comprising, after said drawing step, the step of:
coating a glue layer: the console controls the glue spreader to coat a protective glue layer on the drawn and molded optical fiber, and the console controls the curing machine to cure the protective glue layer coated outside the optical fiber;
coiling fiber: the console controls the fiber coiling wheel and the second driving wheel to rotate at the same speed, so that the optical fibers coated with the protective glue layer are wound on the fiber coiling wheel.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010371255.4A CN113620592A (en) | 2020-05-06 | 2020-05-06 | Optical fiber drawing equipment and optical fiber drawing method |
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| CN202010371255.4A CN113620592A (en) | 2020-05-06 | 2020-05-06 | Optical fiber drawing equipment and optical fiber drawing method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114014533A (en) * | 2021-12-20 | 2022-02-08 | 吉林大学 | Detachable double-guide-rail traction system for polymer-based material and optical fiber drawing method |
| CN114442231A (en) * | 2022-01-24 | 2022-05-06 | 中国科学院上海光学精密机械研究所 | Optical fiber tapering device of long taper zone |
-
2020
- 2020-05-06 CN CN202010371255.4A patent/CN113620592A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114014533A (en) * | 2021-12-20 | 2022-02-08 | 吉林大学 | Detachable double-guide-rail traction system for polymer-based material and optical fiber drawing method |
| CN114442231A (en) * | 2022-01-24 | 2022-05-06 | 中国科学院上海光学精密机械研究所 | Optical fiber tapering device of long taper zone |
| CN114442231B (en) * | 2022-01-24 | 2023-09-01 | 中国科学院上海光学精密机械研究所 | Optical fiber tapering device in long cone area |
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