Repair device for OVD deposition and control method thereof

Abstract

The present application relates to a repair device for OVD deposition and a control method thereof, the device comprising: a deposition blowtorch moving along an axis direction of an optical fiber preform and used for spraying a reaction gas toward the optical fiber preform; the repair blowtorch and the deposition blowtorch are located on different sides of the optical fiber preform, and the repair blowtorch is used for spraying combustion gas towards the fracture risk area; a camera of the particle monitor is arranged towards the fracture risk area of the optical fiber preform, and the particle monitor is used for monitoring particle state parameters of the space where the fracture risk area is located when the deposition blowtorch moves to the periphery of the fracture risk area; the control unit controls the repairing blowtorch to spray out combustion gas according to the particle state parameters of the space where the fracture risk area is located; according to the method, the loose body deposited on the optical fiber preform can be repaired on line in the OVD deposition process, and the fracture risk is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of optical fiber preform manufacturing, and in particular to a repair device for OVD deposition and a control method thereof. Background Art

[0002] The production of optical fiber preform involves an OVD deposition process. During the OVD deposition process, a deposition torch moves back and forth in a deposition chamber. The deposition torch sprays gaseous raw materials onto the core rod through an oxyhydrogen flame, and finally reacts and deposits to form a loose body of silica.

[0003] The silica particles generated after the raw materials react are submicron-sized and have an individual temperature of about 1000°C. They move at high speed with the oxyhydrogen flame and then adhere to the surface of the core rod. The silica particles are affected by airflow, temperature, morphology, etc. and show irregular motion. The condensed volume of each silica particle is also inconsistent, which causes the silica loose body to break at any time due to stress. Summary of the invention

[0004] Based on the above description, the present application provides a repair device for OVD deposition and a control method thereof to solve the problem of the risk of rupture of the loose body deposited on the optical fiber preform.

[0005] According to a first aspect, the present application provides a repair device for OVD deposition, comprising:

[0006] A deposition torch is disposed outside the optical fiber preform and moves along the axis of the optical fiber preform, and is used to spray reaction gas toward the optical fiber preform;

[0007] a repair torch, wherein the repair torch and the deposition torch are located at different sides of the optical fiber preform, and the repair torch is used to spray combustion gas toward a breakage risk area of ​​the optical fiber preform;

[0008] a particle monitor, wherein a camera of the particle monitor is arranged toward the rupture risk area of ​​the optical fiber preform, and the particle monitor is used to monitor the particle state parameters in the space where the rupture risk area is located when the deposition torch moves around the rupture risk area; and

[0009] A control unit is respectively connected to the repair torch and the particle monitor signal, and the control unit controls the repair torch to spray combustion gas according to the particle state parameters of the space where the rupture risk area is located; the rupture risk area includes an edge area on at least one side of the axial direction of the optical fiber preform rod.

[0010] In one or more embodiments, the repair torch is configured to be movable to one side of the rupture risk area of ​​the optical fiber preform; or

[0011] The repair torch is arranged toward one side of the breakage risk area of ​​the optical fiber preform.

[0012] In one or more embodiments, the repair torch is configured to be movable to one side of the standby position of the deposition torch; the camera of the particle monitor is disposed close to the standby position of the deposition torch, and the camera is rotatably disposed;

[0013] When the deposition torch returns to the standby position, the control unit controls the particle monitor to rotate the camera and monitor the particle state parameters in the space where the nozzle of the deposition torch is located, so as to control the repair torch to spray the cleaning gas.

[0014] In one or more embodiments, the standby position of the deposition torch is located on one side of the axial direction of the optical fiber preform, and the rupture risk area is an edge area of ​​the optical fiber preform close to the standby position of the deposition torch.

[0015] In one or more embodiments, the particle monitor includes a camera and an information processing unit in communication connection;

[0016] The camera includes an infrared camera unit and a high-definition camera unit, the infrared camera unit is used to collect heat distribution images, and the high-definition camera unit is used to collect particle space images;

[0017] The information processing unit is used to determine the particle state parameters of the monitored particles according to the heat distribution image and the particle space image, and the particle state parameters include particle temperature, particle size and particle movement rate.

[0018] According to a second aspect, the present application provides a control method for a repair device for OVD deposition, comprising:

[0019] Turn on the deposition torch, move the deposition torch along the axial direction of the optical fiber preform and spray the reaction gas to the optical fiber preform, and the repair torch is in a standby state;

[0020] When the deposition torch moves to the vicinity of the breakage risk area of ​​the optical fiber preform, the control unit controls the particle monitor to monitor the particle state parameters in the space where the breakage risk area is located;

[0021] When the particle state parameter meets the first preset condition, the control unit controls the repair torch to spray a first flow rate of combustion gas toward the rupture risk area;

[0022] Wherein, the particle state parameters include particle temperature, particle size and particle movement speed;

[0023] The first preset condition is: the ratio of the number of particles whose particle temperature is greater than the first temperature threshold and whose particle size is greater than the first size threshold to the total number of monitored particles is greater than the first ratio threshold, and at the same time, the ratio of the number of particles whose particle temperature is greater than the first temperature threshold and whose particle movement speed is greater than the first speed threshold to the total number of monitored particles is less than the second ratio threshold.

[0024] In one or more embodiments, further comprising:

[0025] After the repair torch sprays the combustion gas at a first flow rate for a first preset time, if the particle state parameter still satisfies the first preset condition, the control unit controls the repair torch to spray the combustion gas at a second flow rate for a second preset time and then returns to the standby state;

[0026] Among them, the second flow rate is greater than the first flow rate; the second preset time is greater than the first preset time.

[0027] In one or more embodiments, the repair torch is configured to be movable to one side of the standby position of the deposition torch; the camera of the particle monitor is disposed close to the standby position of the deposition torch and is rotatable; and the control method further comprises:

[0028] When the deposition torch returns to the standby position after spraying for a preset spraying time, the control unit controls the camera of the particle monitor to rotate to monitor the particle state parameters in the space where the nozzle of the deposition torch is located;

[0029] When the particle state parameter satisfies a second preset condition, the control unit controls the repair torch to move to one side of the standby position of the deposition torch, and sprays a cleaning gas of a third flow rate toward the nozzle of the deposition torch;

[0030] Among them, the second preset condition is: the proportion of the number of particles whose particle temperature is greater than the second temperature threshold and whose particle size is greater than the second size threshold to the total number of monitored particles is greater than the third proportion threshold, and at the same time, the proportion of the number of particles whose particle temperature is greater than the second temperature threshold and whose particle movement rate is greater than the second rate threshold to the total number of monitored particles is less than the fourth proportion threshold.

[0031] In one or more embodiments, the second temperature threshold is lower than the first temperature threshold, the second size threshold is higher than the first size threshold, the second rate threshold is lower than the first rate threshold, the third ratio threshold is higher than the first ratio threshold, and the fourth ratio threshold is lower than the second ratio threshold.

[0032] In one or more embodiments, further comprising:

[0033] After the repair torch sprays the cleaning gas at a third flow rate for a third preset time, if the particle state parameter still meets the second preset condition, the control unit controls the repair torch to spray the cleaning gas at a fourth flow rate for a fourth preset time and then returns to the standby state;

[0034] Among them, the fourth flow rate is greater than the third flow rate; the fourth preset time is greater than the third preset time. Compared with the prior art, the technical solution of the present application has the following beneficial technical effects:

[0035] A deposition torch, a repair torch, a particle monitor and a control unit are provided, and the edge area on at least one side of the axial direction of the optical fiber preform is used as a rupture risk area. The deposition torch moves back and forth along the axial direction of the optical fiber preform and sprays reaction gas. When the deposition torch moves to the rupture risk area of ​​the optical fiber preform, the particle monitor uses a camera to monitor the particle state parameters of the space where the rupture risk area is located. The control unit can control the repair torch to spray combustion gas toward the rupture risk area according to the particle state parameters of the space where the rupture risk area is located, thereby helping to increase the deposition temperature of silica particles in the rupture risk area, reduce the rupture risk of the edge area of ​​the optical fiber preform, and improve the quality of the optical fiber preform. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A schematic diagram of the structure of a repair device for OVD deposition in a use state provided by an embodiment of the present application;

[0037] Figure 2 A schematic structural diagram of a repair device for OVD deposition in another use state provided by another embodiment of the present application;

[0038] Figure 3 A schematic flow chart of a control method for a repair device for OVD deposition provided in one embodiment of the present application;

[0039] Figure 4 A schematic flow chart of a control method for a repair device for OVD deposition provided in accordance with another embodiment of the present application.

[0040] Description of reference numerals:

[0041] Deposition torch 10;

[0042] Repair blowtorch 20;

[0043] Particle monitor 30, camera 31, information processing unit 32;

[0044] A control unit 40;

[0045] Optical fiber preform L;

[0046] Rupture risk area r;

[0047] First direction F1, second direction F2. DETAILED DESCRIPTION

[0048] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0050] It is understood that when an element is considered to be "connected" to another element, it can be directly connected to the other element, or connected to the other element through an intermediate element. The "connection" in the following embodiments should be understood as "electrical connection", "communication connection", etc. if the connected circuits, modules, units, etc. have electrical signals or data transmission between each other.

[0051] See also Figure 1 , Figure 1 A schematic structural diagram of a repair device for OVD deposition provided in one embodiment of the present application is shown. The repair device for OVD deposition provided in one embodiment of the present application includes a deposition torch 10, a repair torch 20, a particle monitor 30 and a control unit 40. The deposition torch 10 is arranged outside the optical fiber preform L and is movable along the axial direction of the optical fiber preform L. The deposition torch 10 is used to spray reaction gas toward the optical fiber preform L. The repair torch 20 and the deposition torch 10 are located on different sides of the optical fiber preform L, and the repair torch 20 is used to spray combustion gas toward the rupture risk area r of the optical fiber preform L. The camera 31 of the particle monitor 30 is arranged toward the rupture risk area r of the optical fiber preform L. The particle monitor 30 is used to monitor the particle state parameters of the space where the rupture risk area r is located when the deposition torch 10 moves to the rupture risk area r. The control unit 40 is connected to the repair torch 20 and the particle monitor 30 by signal respectively. The control unit 40 controls the repair torch 20 to spray combustion gas according to the particle state parameters of the space where the rupture risk area r is located. The rupture risk area r includes an edge area on at least one side of the axial direction of the optical fiber preform L. The first direction F1 is parallel to the axial direction of the optical fiber preform L.

[0052] It should be noted that the repair device of the present embodiment is installed in the deposition chamber, and the deposition and repair process of the optical fiber preform L is completed in the deposition chamber. The optical fiber preform L is a core rod in the initial state, and the core rod is installed in the deposition chamber. In the present embodiment, the optical fiber preform L can be rotatably arranged along its axial direction so that the loose body can be fully deposited on the circumferential surface of the optical fiber preform L. In the process of depositing the loose body on the optical fiber preform L, since the edge area on one side of the axial direction of the optical fiber preform L belongs to the starting deposition area, and the edge area on the other side belongs to the ending deposition area, the deposition temperature of the edge areas on both sides is relatively unstable, resulting in a greater risk of rupture of the loose body deposited in the edge areas on both sides. Therefore, in the present embodiment, the rupture risk area r of the optical fiber preform L includes the edge area on at least one side of the axial direction of the optical fiber preform L, and the edge area on at least one side of the optical fiber preform L is monitored and repaired.

[0053] Specifically, the deposition torch 10 is generally made of quartz glass, and the core temperature during deposition is relatively high, about 1200°C. During the deposition process, the deposition torch 10 reciprocates along the first direction F1, and at the same time sprays reaction gas toward the optical fiber preform L, and the reaction gas includes hydrogen, oxygen and reaction raw materials (such as silicon tetrachloride) to generate silica particles and deposit them on the optical fiber preform L, and at the same time generate a high-temperature flame. It should be noted that the deposition torch 10 can be reciprocated along the first direction F1 by setting a guide rail and a motor. The setting of the guide rail and the motor belongs to conventional mechanical technology, and this embodiment will not be described in detail here. In this embodiment, the number of deposition torches 10 can be one or more, and multiple deposition torches 10 are arranged at intervals, for example, one, two, three, or four deposition torches 10 can be set, which can be determined according to the length of the optical fiber preform L and the deposition time, etc., and this embodiment is not limited here.

[0054] The repair torch 20 and the deposition torch 10 are located on different sides of the optical fiber preform L. The repair torch 20 is used to spray combustion gas toward the rupture risk area r of the optical fiber preform L. The combustion gas is used to increase heat to compensate for the deposition temperature of the rupture risk area r to reduce the occurrence of rupture. In this embodiment, the combustion gas includes hydrogen and oxygen. Further, nitrogen can be added to the combustion gas to prevent hydrogen from dispersing, thereby allowing the combustion flame to gather and further increase the temperature.

[0055] The particle monitor 30 is used to monitor the state parameters of silica particles floating in the space where the rupture risk area r is located when the deposition torch 10 moves to the vicinity of the rupture risk area r, wherein the camera 31 of the particle monitor 30 is set toward the rupture risk area r of the optical fiber preform L, and the camera 31 and the repair torch 20 are at different circumferential positions of the optical fiber preform L. The product particle image in the space where the rupture risk area r is located is monitored by the camera 31, and the particle state parameters are determined by image analysis, and the particle state parameters may include particle temperature, particle size and particle movement rate. It should be noted that the position of the deposition torch 10 can be detected by setting a position sensor. When the deposition torch 10 moves to the vicinity of the rupture risk area r of the optical fiber preform L or a specified position, the position sensor feeds back the position signal to the control unit 40, and the control unit 40 controls the particle monitor 30 to monitor the particle state parameters in the space where the rupture risk area r of the optical fiber preform L is located.

[0056] It can be understood that the number of the repair torch 20 and the particle monitor 30 can be one or two. For example, a repair torch 20 and a particle monitor 30 are set near the edge area on one side of the optical fiber preform L, or a repair torch 20 and a particle monitor 30 are set near the edge area on both sides of the optical fiber preform L. The specific setting can be reasonably made according to the actual process conditions and cost considerations, and this embodiment does not limit it here.

[0057] The control unit 40 may be a microcontroller or an embedded controller. The control unit 40 is connected to the repair torch 20 and the particle monitor 30 by signals respectively. The control unit 40 controls the action of the repair torch 20 according to the particle state parameters of the space where the rupture risk area r is located. For example, according to the particle state parameters of the space where the rupture risk area r is located, if the temperature, size or movement rate of a large part of the currently monitored silica particles does not meet the sufficient deposition conditions or meet the deposition rupture conditions, the control unit 40 controls the repair torch 20 to spray the combustion gas and controls the parameters such as the spray flow rate and time.

[0058] In this embodiment, before or during deposition, the deposition torch 10 reciprocates along the axial direction of the optical fiber preform L and sprays reaction gas. When the deposition torch 10 moves to the rupture risk area r of the optical fiber preform L, the control unit 40 controls the camera 31 of the particle monitor 30 to monitor the particle state parameters of the space where the rupture risk area r is located. The control unit 40 can control the repair torch 20 to spray combustion gas toward the rupture risk area r according to the particle state parameters of the space where the rupture risk area r is located, thereby helping to increase the deposition temperature of the rupture risk area r, reduce the rupture risk of the optical fiber preform L, and improve the quality of the optical fiber preform L.

[0059] In some embodiments, the repair torch 20 is configured to be movable to one side of the rupture risk region r of the optical fiber preform L. Specifically, the control unit 40 can control the repair torch 20 to move from the standby position along the first direction F1 to the rupture risk region r of the optical fiber preform L, so that the repair torch 20 can spray combustion gas toward the rupture risk region r, or reciprocate along the first direction F1 in the process of spraying combustion gas to expand the spray range and fully cover the vicinity of the rupture risk region r. It should be noted that the movable function of the repair torch 20 along the first direction F1 can be realized by setting a guide rail and a motor. The setting of the guide rail and the motor belongs to conventional mechanical technology, and this embodiment will not be described in detail here.

[0060] Alternatively, the repair torch 20 is disposed toward one side of the rupture risk region r of the optical fiber preform L. Specifically, the repair torch 20 and the camera 31 of the particle monitor 30 are both disposed toward the rupture risk region r of the optical fiber preform L, and the repair torch 20 and the camera 31 of the particle monitor 30 are disposed opposite to each other, so as to realize the monitoring and repair process of the product particles in the space where the rupture risk region r is located.

[0061] In the OVD deposition process of the related art, the deposition torch 10 may accumulate unnecessary silica particles at the nozzle due to high temperature, which may interfere with the flame and normal silica particle deposition and may even cause the loose body to rupture and shut down during the OVD deposition process.

[0062] Based on this, see Figure 1 and Figure 2 In some embodiments, the repair torch 20 is configured to be movable to one side of the standby position of the deposition torch 10; the camera 31 of the particle monitor 30 is arranged close to the standby position of the deposition torch 10, and the camera 31 can be rotatably arranged; when the deposition torch 10 returns to the standby position, the control unit 40 controls the particle monitor 30 to rotate the camera 31 and monitor the particle state parameters in the space where the nozzle of the deposition torch 10 is located, so as to control the repair torch 20 to spray the cleaning gas.

[0063] It should be noted that, in the present embodiment, the standby position of the repair torch 20 and the standby position of the deposition torch 10 are both located near one side of the axial direction of the optical fiber preform L, and are arranged relatively to each other along the second direction F2. The repair torch 20 can be moved along the second direction F2 to the vicinity of the standby position of the deposition torch 10, and the camera 31 of the particle monitor 30 can be rotated about 90° so that the camera 31 can be directed toward the nozzle of the deposition torch 10 located at the standby position.

[0064] Specifically, in the later stage of deposition, the deposition torch 10 may accumulate unnecessary silica particles at the nozzle due to high temperature. When the deposition torch 10 returns to the standby position, the control unit 40 controls the particle monitor 30 to rotate the camera 31 to monitor the state parameters of the silica particles floating in the space where the nozzle of the deposition torch 10 is located. The control unit 40 controls the action of the repair torch 20 according to the particle state parameters of the space where the nozzle of the deposition torch 10 is located. For example, according to the particle state parameters of the space where the nozzle of the deposition torch 10 is located, it is analyzed that the temperature, size or movement rate of most of the current silica particles meet the cleaning conditions, and the control unit 40 controls the repair torch 20 to move from the standby position along the second direction F2 to the vicinity of the standby position of the deposition torch 10, spray cleaning gas toward the nozzle of the deposition torch 10, and control the spray flow rate, time and other parameters. It should be noted that nitrogen can be used as the cleaning gas, and the silicon dioxide particles deposited on the nozzle of the deposition torch 10 can be purged with nitrogen to reduce interference with the reaction flame, so that subsequent silicon dioxide particles can be normally deposited on the optical fiber preform L, reducing the risk of shutdown due to rupture of the loose body during the OVD deposition process.

[0065] In some embodiments, the standby position of the deposition torch 10 is located on one side of the axial direction of the optical fiber preform L, and the rupture risk area r is an edge area of ​​the optical fiber preform L close to the standby position of the deposition torch 10 .

[0066] Specifically, since the deposition torch 10 moves from the standby position along the first direction F1 and sprays the reaction gas toward the optical fiber preform L, the temperature of the edge area on the side of the standby position of the optical fiber preform L close to the deposition torch 10 rises from the initial low temperature to a high temperature, and the temperature change is large. The risk of rupture of the deposited loose body of the optical fiber preform L in the edge area on this side is higher than that in the edge area on the other side. According to the experience of the OVD deposition process, there are more ruptures in the edge area of ​​the optical fiber preform L close to the standby position of the deposition torch 10. Considering the control cost at the same time, in this embodiment, the edge area of ​​the optical fiber preform L close to the standby position of the deposition torch 10 is monitored and repaired.

[0067] In some embodiments, the particle monitor 30 includes a camera 31 and an information processing unit 32 that are communicatively connected; the camera 31 includes an infrared camera unit and a high-definition camera unit, the infrared camera unit is used to collect heat distribution images, and the high-definition camera unit is used to collect particle space images; the information processing unit 32 is used to determine the particle state parameters of the monitored particles based on the heat distribution image and the particle space image, and the particle state parameters include particle temperature, particle size and particle movement rate.

[0068] Specifically, the camera 31 includes an infrared camera unit and a high-definition camera unit, and collects information to the information processing unit 32. The infrared camera unit can collect heat distribution images of the monitored object (silicon dioxide particles) within the specified monitoring range of 100*100mm to provide temperature data with a temperature range of 50~2000℃, an accuracy of ±0.2℃, and a sampling frequency of 1μs~100s. The high-definition camera unit can capture particle spatial images of the monitored object (silicon dioxide particles) within the specified monitoring range of 100*100mm to provide particle diameter data with a diameter range of 0.1~100mm and a sampling frequency of 1μs~100s. It should be noted that the two camera units each have 50 channels and can monitor 0~50 silicon dioxide particles at the same time. The information processing unit 32 determines the diameter of each monitored particle by calculating the pixel coordinates based on the particle space image collected in real time, and calculates the movement rate of each monitored particle based on the different coordinates of the monitored particles at different time points. The particle movement rate is in the range of 2m / s to 50m / s. The infrared camera unit and the high-definition camera unit share the same position coordinates. The information processing unit 32 determines the temperature of each monitored particle based on the heat distribution image collected in real time. In this way, the particle state parameters of the monitored particles can be accurately determined based on the heat distribution image and the particle space image.

[0069] See also Figure 1 and Figure 3 Based on the same inventive concept, the embodiment of the present application also provides a control method for a repair device for OVD deposition, comprising:

[0070] S301, turn on the deposition torch 10, move along the axial direction of the optical fiber preform L and spray the reaction gas to the optical fiber preform L, and the repair torch 20 is in a standby state.

[0071] S302, when the deposition torch 10 moves to the vicinity of the breakage risk region r of the optical fiber preform L, the control unit 40 controls the particle monitor 30 to monitor the particle state parameters in the space where the breakage risk region r is located.

[0072] S303: When the particle state parameter meets the first preset condition, the control unit 40 controls the repair torch 20 to spray a first flow rate of combustion gas toward the rupture risk area r.

[0073] Among them, the particle state parameters include particle temperature, particle size and particle movement rate; the first preset condition is: the proportion of the number of particles whose particle temperature is greater than the first temperature threshold and whose particle size is greater than the first size threshold to the total number of monitored particles is greater than the first proportion threshold, and at the same time, the proportion of the number of particles whose particle temperature is greater than the first temperature threshold and whose particle movement rate is greater than the first rate threshold to the total number of monitored particles is less than the second proportion threshold. In this embodiment, the first temperature threshold is 450° to 550°, and the specific values ​​can be 450°, 480°, 500°, 520° or 550°. The first size threshold is 0.8mm to 1.2mm, and the specific values ​​can be 0.8mm, 0.9mm, 1mm, 1.1mm or 1.2mm. The first rate threshold is 18m / s to 22m / s, and the specific values ​​can be 18m / s, 19m / s, 20m / s, 21m / s or 22m / s. The first ratio threshold is 25% to 35%, specifically 25%, 30% or 35%. The second ratio threshold is 75% to 85%, specifically 75%, 80% or 85%.

[0074] Specifically, the deposition torch 10 starts from the standby position and moves along the first direction F1, while spraying hydrogen, oxygen and reaction raw materials toward the optical fiber preform L. The repair torch 20 is in a standby state, spraying a combustion gas of a standby flow rate, and the standby flow rate is small, and the combustion gas includes hydrogen and oxygen. Furthermore, nitrogen can be added to the combustion gas to avoid hydrogen dispersion, thereby allowing the combustion flame to gather and further increase the temperature. In this embodiment, the first flow rate of the combustion gas is 2.5 to 3.5 times the standby flow rate, specifically 2.5 times, 3 times or 3.5 times, which can be set according to actual conditions.

[0075] In a specific embodiment, when the deposition torch 10 moves to the vicinity of the fracture risk area r or a specified position of the optical fiber preform L, the position sensor can detect and feed back to the control unit 40, and the control unit 40 controls the particle monitor 30 to monitor the particle state parameters in the space where the fracture risk area r is located. The particle monitor 30 or the control unit 40 can calculate the ratio a1 of the number of particles with a particle temperature greater than 500° and a particle size greater than 1 mm to the total number of monitored particles, and the ratio b1 of the number of particles with a particle temperature greater than 500° and a particle movement speed greater than 20 m / s to the total number of monitored particles. When a1 is greater than When a1 is less than or equal to 30% and b1 is less than 80%, it is judged that the loose body deposited in the rupture risk area r may rupture at any time, and the control unit 40 controls the repair torch 20 to move along the first direction F1 to the rupture risk area r of the optical fiber preform L, and sprays hydrogen and oxygen at 3 times the standby flow rate, while the nitrogen flow rate remains unchanged, until a1 is less than or equal to 30%, and / or b1 is greater than or equal to 80%, the repair torch 20 returns to the standby state, in this way, the deposition condition of the rupture risk area r of the optical fiber preform L is monitored in real time and repaired online, so as to reduce the risk of rupture of the loose body and improve the quality of the optical fiber preform L.

[0076] In some embodiments, after the repair torch 20 sprays a first flow rate of combustion gas for a first preset time, if the particle state parameter still satisfies the first preset condition, the control unit 40 controls the repair torch 20 to spray a second flow rate of combustion gas for a second preset time and then returns to the standby state; the second flow rate is greater than the first flow rate; and the second preset time is greater than the first preset time.

[0077] Specifically, in this embodiment, the second flow rate of the combustion gas is 4.5 to 5.5 times the standby flow rate, and can be 4.5, 5 or 5.5 times. The first preset time is 2.5 to 3.5 minutes, and can be 2.5, 3 or 3.5 minutes. The second preset time is 4.5 to 5.5 minutes, and can be 4.5, 5 or 5.5 minutes.

[0078] In a specific embodiment, the control unit 40 controls the repair torch 20 to spray hydrogen and oxygen at 3 times the standby flow rate for 3 minutes. If the particle state parameter still meets the first preset condition, the control unit 40 controls the repair torch 20 to spray hydrogen and oxygen at 5 times the standby flow rate for 5 minutes and then returns to the standby state. In this way, during the repair process, the spray flow rate and spray time of the repair torch 20 are adjusted according to the real-time monitored particle state parameters to accurately control the repair effect, so that the cracking ratio of the silica loose body in the OVD deposition stage is reduced by 40%, and the quality of the optical fiber preform L is effectively improved.

[0079] See also Figure 1, Figure 2 and 4 In some embodiments, the repair torch 20 is configured to be movable to one side of the standby position of the deposition torch 10; the camera 31 of the particle monitor 30 is disposed near the standby position of the deposition torch 10 and is rotatable; the control method of the present application further includes:

[0080] S401 , when the deposition torch 10 returns to the standby position after spraying for a preset spraying time, the control unit 40 controls the camera 31 of the particle monitor 30 to rotate to monitor the particle state parameters in the space where the nozzle of the deposition torch 10 is located.

[0081] S402: When the particle state parameter meets the second preset condition, the control unit 40 controls the repair torch 20 to move to one side of the standby position of the deposition torch 10, and sprays a cleaning gas of a third flow rate toward the nozzle of the deposition torch 10. In this embodiment, the cleaning gas may be nitrogen.

[0082] Among them, the second preset condition is: the proportion of the number of particles whose particle temperature is greater than the second temperature threshold and whose particle size is greater than the second size threshold to the total number of monitored particles is greater than the third proportion threshold, and the proportion of the number of particles whose particle temperature is greater than the second temperature threshold and whose particle movement speed is greater than the second speed threshold to the total number of monitored particles is less than the fourth proportion threshold. Further, the second temperature threshold is less than the first temperature threshold, the second size threshold is greater than the first size threshold, the second speed threshold is less than the first speed threshold, the third proportion threshold is greater than the first proportion threshold, and the fourth proportion threshold is less than the second proportion threshold. In this embodiment, the second temperature threshold is 350° to 450°, and the specific values ​​are 350°, 380°, 400°, 420° or 450°. The first size threshold is 2.5mm to 3.5mm, and the specific values ​​are 2.5mm, 2.8mm, 3mm, 3.2mm or 3.5mm. The first speed threshold is 8m / s to 12m / s, and the specific values ​​are 8m / s, 9m / s, 10m / s, 11m / s or 12m / s. The first ratio threshold is 45% to 55%, specifically 45%, 50% or 55%, and the second ratio threshold is 45% to 55%, specifically 45%, 50% or 55%. Further, in this embodiment, the third flow rate of the cleaning gas is 3.5 to 4.5 times the standby flow rate, specifically 3.5 times, 4 times or 4.5 times, which can be set according to actual conditions.

[0083] In a specific embodiment, at the end of deposition, the deposition torch 10 returns to the standby position along the first direction F1, that is, when the deposition torch 10 returns to the standby position after spraying the preset spraying time, the control unit 40 controls the camera 31 of the particle monitor 30 to rotate to monitor the particle state parameters in the space where the nozzle of the deposition torch 10 is located. The particle monitor 30 or the control unit 40 can calculate the proportion a2 of the number of particles with a particle temperature greater than 400° and a particle size greater than 3 mm to the total number of monitored particles, and the proportion b2 of the number of particles with a particle temperature greater than 400° and a particle movement speed greater than 10 m / s to the total number of monitored particles. When a2 is greater than 50% and b2 is less than 50%, it is determined that the deposition torch 10 is depositing. If there are too many silica particles deposited on the deposition torch 10, the control unit 40 controls the repair torch 20 to move from the standby position along the second direction F2 to the vicinity of the standby position of the deposition torch 10, and sprays nitrogen gas at 4 times the standby flow rate, while hydrogen and oxygen maintain the standby flow rate, until a2 is less than or equal to 50%, and / or b2 is greater than or equal to 50%, the repair torch 20 returns to the standby state, in this way, the excessive silica particles deposited on the deposition torch 10 are monitored and repaired online, and the silica particles deposited on the nozzle of the deposition torch 10 are purged with nitrogen to reduce the interference with the reaction flame, so that the subsequent silica particles can be normally deposited on the optical fiber preform L, and the risk of shutdown due to rupture of the loose body during the OVD deposition process is reduced.

[0084] In some embodiments, the control method of the present application further includes:

[0085] After the repair torch 20 sprays the cleaning gas at a third flow rate for a third preset time, if the particle state parameter still satisfies the second preset condition, the control unit 40 controls the repair torch 20 to spray the cleaning gas at a fourth flow rate for a fourth preset time and then returns to the standby state; wherein the fourth flow rate is greater than the third flow rate; and the fourth preset time is greater than the third preset time.

[0086] Specifically, in this embodiment, the fourth flow rate of the cleaning gas is 5.5 to 6.5 times the standby flow rate, and can be 5.5 times, 6 times or 6.5 times. The first preset time is 0.8 min to 1.2 min, and can be 0.8 min, 1 min or 1.2 min. The second preset time is 1.8 min to 2.2 min, and can be 1.8 min, 2 min or 2.2 min.

[0087] In a specific embodiment, after the repair torch 20 sprays nitrogen gas at 4 times the standby flow rate for 1 mm, if the particle state parameter still meets the second preset condition, the control unit 40 controls the repair torch 20 to spray nitrogen gas at 6 times the standby flow rate for 2 mm and then returns to the standby state. In this way, during the process of cleaning the nozzle of the deposition torch 10, the spray flow rate and spray time of the repair torch 20 are adjusted according to the particle state parameters monitored in real time to accurately control the cleaning effect, effectively purge the silicon dioxide particles deposited on the nozzle of the deposition torch 10, and extend the service life of the deposition torch 10 by 150%.

[0088] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A repair device for OVD deposition, characterized in that: include: A deposition torch is disposed outside the optical fiber preform and is movable along the axis of the optical fiber preform, and is used to spray reaction gas toward the optical fiber preform; a repair torch, wherein the repair torch and the deposition torch are located at different sides of the optical fiber preform, and the repair torch is used to spray combustion gas toward a breakage risk area of ​​the optical fiber preform; A particle monitor, wherein a camera of the particle monitor is arranged toward the rupture risk area of ​​the optical fiber preform, and the particle monitor is used to monitor the particle state parameters in the space where the rupture risk area is located when the deposition torch moves around the rupture risk area; and A control unit is respectively connected to the repair torch and the particle monitor signal, and the control unit controls the repair torch to spray combustion gas according to the particle state parameters of the space where the rupture risk area is located; the rupture risk area includes an edge area on at least one side of the axial direction of the optical fiber preform rod.

2. The repair device for OVD deposition according to claim 1, characterized in that: The repair torch is configured to be movable to one side of the breakage risk area of ​​the optical fiber preform; or The repair torch is arranged toward one side of the breakage risk area of ​​the optical fiber preform.

3. The repair device for OVD deposition according to claim 1, characterized in that: The repair torch is configured to be movable to one side of the standby position of the deposition torch; the camera of the particle monitor is arranged close to the standby position of the deposition torch, and the camera can be rotatably arranged; When the deposition torch returns to the standby position, the control unit controls the particle monitor to rotate the camera and monitor the particle state parameters in the space where the nozzle of the deposition torch is located, so as to control the repair torch to spray the cleaning gas.

4. The repair device for OVD deposition according to claim 1, characterized in that: The standby position of the deposition torch is located on one side of the axial direction of the optical fiber preform, and the rupture risk area is an edge area of ​​the optical fiber preform close to the standby position of the deposition torch.

5. The repair device for OVD deposition according to claim 1, characterized in that: The particle monitor includes a camera and an information processing unit in communication connection; The camera includes an infrared camera unit and a high-definition camera unit, the infrared camera unit is used to collect heat distribution images, and the high-definition camera unit is used to collect particle space images; The information processing unit is used to determine the particle state parameters of the monitored particles according to the heat distribution image and the particle space image, and the particle state parameters include particle temperature, particle size and particle movement rate.

6. A control method for a repair device for OVD deposition, characterized in that: include: Turn on the deposition torch, which moves along the axis of the optical fiber preform and sprays reaction gas to the optical fiber preform, and the repair torch is in a standby state; When the deposition torch moves to the vicinity of the breakage risk area of ​​the optical fiber preform, the control unit controls the particle monitor to monitor the particle state parameters in the space where the breakage risk area is located; When the particle state parameter meets the first preset condition, the control unit controls the repair torch to spray a first flow rate of combustion gas toward the rupture risk area; Wherein, the particle state parameters include particle temperature, particle size and particle movement speed; The first preset condition is: the ratio of the number of particles whose particle temperature is greater than the first temperature threshold and whose particle size is greater than the first size threshold to the total number of monitored particles is greater than the first ratio threshold, and at the same time, the ratio of the number of particles whose particle temperature is greater than the first temperature threshold and whose particle movement speed is greater than the first speed threshold to the total number of monitored particles is less than the second ratio threshold.

7. The control method of the repair device for OVD deposition according to claim 6, characterized in that: Also includes: After the repair torch sprays the combustion gas at a first flow rate for a first preset time, if the particle state parameter still satisfies the first preset condition, the control unit controls the repair torch to spray the combustion gas at a second flow rate for a second preset time and then returns to the standby state; Among them, the second flow rate is greater than the first flow rate; the second preset time is greater than the first preset time.

8. The control method of the repair device for OVD deposition according to claim 6, characterized in that: The repair torch is configured to be movable to one side of the standby position of the deposition torch; the camera of the particle monitor is arranged close to the standby position of the deposition torch and can be rotatably arranged; The control method further comprises: When the deposition torch returns to the standby position after spraying for a preset spraying time, the control unit controls the camera of the particle monitor to rotate to monitor the particle state parameters in the space where the nozzle of the deposition torch is located; When the particle state parameter satisfies a second preset condition, the control unit controls the repair torch to move to one side of the standby position of the deposition torch, and sprays a cleaning gas of a third flow rate toward the nozzle of the deposition torch; Among them, the second preset condition is: the proportion of the number of particles whose particle temperature is greater than the second temperature threshold and whose particle size is greater than the second size threshold to the total number of monitored particles is greater than the third proportion threshold, and at the same time, the proportion of the number of particles whose particle temperature is greater than the second temperature threshold and whose particle movement rate is greater than the second rate threshold to the total number of monitored particles is less than the fourth proportion threshold.

9. The control method of the repair device for OVD deposition according to claim 8, characterized in that: The second temperature threshold is lower than the first temperature threshold, the second size threshold is higher than the first size threshold, the second rate threshold is lower than the first rate threshold, the third ratio threshold is higher than the first ratio threshold, and the fourth ratio threshold is lower than the second ratio threshold.

10. The control method of the repair device for OVD deposition according to claim 9, characterized in that: Also includes: After the repair torch sprays the cleaning gas at a third flow rate for a third preset time, if the particle state parameter still meets the second preset condition, the control unit controls the repair torch to spray the cleaning gas at a fourth flow rate for a fourth preset time and then returns to the standby state; Among them, the fourth flow rate is greater than the third flow rate; the fourth preset time is greater than the third preset time.

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