Assembly structure of optical fiber drawing furnace

Abstract

The utility model relates to the technical field of optical fiber production equipment, in particular to an assembly structure of an optical fiber drawing furnace, aims to solve the technical problem of overcoming the defects of assembly and sealing in the prior art, and is mainly realized by the following technical scheme: the assembly structure of the optical fiber drawing furnace comprises an upper air sealing plate, a lower air sealing plate and a central pipe, the fixing piece comprises a locking bolt and a sinking groove hole, the sealing piece is arranged between the upper air sealing plate and the lower air sealing plate, the sealing piece comprises a sealing protrusion and a plurality of sealing clamping strips, the sealing protrusion and the lower air sealing plate are integrally arranged and extend to be arranged at the top of the lower air sealing plate, and the sealing clamping strips are all arranged between the sealing protrusion and the upper air sealing plate. The sealing protrusion is arranged to be matched with the upper air sealing plate in an embedded mode, the gap between the top of the center pipe and the upper air sealing plate can be effectively reduced, the upper air sealing plate and the lower air sealing plate can be effectively sealed even if the center pipe is upwards ejected out of the upper air sealing plate after being heated and expanded, and gas disturbance caused by external air permeation is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of optical fiber production equipment, in particular to an optical fiber drawing furnace assembly structure. Background Art

[0002] In the optical fiber drawing process, the temperature distribution in the furnace is a key factor affecting the quality of the optical fiber, and the temperature distribution in the furnace is mainly affected by the temperature and velocity distribution of the gas inside the drawing furnace. Fluctuations in the airflow will cause fluctuations in the temperature in the furnace, which will cause uneven heating of the preform, which will lead to fluctuations in the optical fiber diameter, changes in the core-to-shell ratio and refractive index distribution, and thus cause optical fiber defects.

[0003] The existing wire drawing heating furnace includes two cavities: one is the inside of the carbon central tube, where the light rod is arranged; the other is the area outside the central tube where the induction coil or the resistance heating coil is located. The two areas are separated by the central tube, and the upper and lower parts are simply sealed by the top and bottom of the central tube. In the actual production process, the central tube will expand and lengthen when heated. Therefore, when assembling the wire drawing furnace, the bottom of the upper air sealing plate will be separated from the top of the central tube by a certain distance to reserve a certain expansion space. If the reserved gap is too long, the top of the central tube cannot be well leaned on the lower surface of the upper air sealing plate, so that the gas inside and outside the central tube is disturbed, which leads to the disorder of the hot zone around the light rod, and then the bare fiber diameter of the optical fiber becomes unstable; if the reserved gap is too short, it is very easy to cause the central tube to directly push open the upper air sealing plate of the wire drawing furnace after the heat expansion, so that the inside of the wire drawing furnace is not sealed, and the outside air enters the furnace cavity, so that the high-temperature light rod will be oxidized, causing an optical fiber production accident. Utility Model Content

[0004] Therefore, the technical problem to be solved by the utility model is to overcome the defects of assembly sealing in the prior art, thereby providing an optical fiber drawing furnace assembly structure.

[0005] The above technical objectives of the utility model are achieved through the following technical solutions:

[0006] An optical fiber drawing furnace assembly structure, comprising an upper gas sealing plate, a lower gas sealing plate and a central tube, wherein a coaxial central tube is arranged in the lower gas sealing plate, a gap is left between the top of the central tube and the bottom of the upper gas sealing plate, and further comprising:

[0007] A fixing part, the fixing part comprises a locking bolt, a countersunk hole and a compression spring, the countersunk hole is opened on the upper gas sealing plate, the compression spring is sleeved on the locking bolt, and the locking bolt passes through the countersunk hole and is fixed on the lower gas sealing plate;

[0008] A sealing member, wherein the sealing member is arranged between an upper air sealing plate and a lower air sealing plate, the sealing member comprises a sealing protrusion and a plurality of sealing clips, the sealing protrusion is integrally arranged with the lower air sealing plate and extends to be arranged on the top of the lower air sealing plate, and the sealing clips are all arranged between the sealing protrusion and the upper air sealing plate.

[0009] By adopting the above technical solution, a sealing protrusion is provided to be embedded in the upper air sealing plate, so that during the overall assembly, the upper air sealing plate and the lower air sealing plate are tightly matched, and the gap between the top of the central tube and the upper air sealing plate can be effectively reduced. Even if the central tube is expanded by heat and pushes the upper air sealing plate upward, the upper air sealing plate and the lower air sealing plate can be effectively sealed to prevent the infiltration of outside air and cause gas disturbance.

[0010] Furthermore, a first through hole is opened through the center of the upper air sealing plate, a first stepped groove extends from the top of the first through hole, a second through hole is opened through the center of the lower air sealing plate, a diameter of the second through hole is larger than that of the first through hole, and a second stepped groove extends near the top of the second through hole.

[0011] By adopting the above technical solution, the existence of the first through hole and the second through hole facilitates the placement of the central tube, and the provision of the first step groove and the second step groove can effectively increase the length of the air circulation path, thereby reducing the possibility of air infiltration and ensuring the sealing effect.

[0012] Furthermore, the upper air sealing plate is provided with a plurality of ventilation holes in a circumferential array, a ventilation chamber is provided at one end of the ventilation hole away from the first through hole, one end of the ventilation hole is connected to the first through hole, and the other end is connected to the ventilation chamber, and a ventilation device is also connected to the upper air sealing plate, and the ventilation device is connected to the ventilation chamber.

[0013] By adopting the above technical solution, the ventilation device is connected to the ventilation cavity so as to ventilate the interior of the upper air sealing plate through the ventilation holes, so as to achieve the air sealing operation inside the upper air sealing plate.

[0014] Furthermore, an upper cooling chamber is opened along the circumference in the upper air sealing plate, and an upper inlet and outlet connected to the upper cooling chamber are provided on the side wall of the upper air sealing plate; a lower cooling chamber is opened along the circumference in the lower air sealing plate, and a lower inlet and outlet connected to the lower cooling chamber are provided on the side wall of the lower air sealing plate.

[0015] By adopting the above technical solution, an upper cooling chamber and a lower cooling chamber are set to dissipate the heat generated during the operation of the optical fiber drawing furnace, and a coolant is circulated through the upper inlet and the lower inlet, and the coolant includes but is not limited to water.

[0016] Furthermore, a clamping ring extends from the bottom of the upper air sealing plate, and the clamping ring is clamped with the top of the lower air sealing plate, and the outer diameter of the clamping ring is equal to the inner diameter of the second stepped groove.

[0017] By adopting the above technical solution, the embedded ring is inserted into the second stepped groove to ensure that the upper air sealing plate can still be connected to the lower air sealing plate even when it is pushed out by the expansion of the central tube, thereby reducing the entry of external air and ensuring that the upper and lower air sealing plates are tightly connected.

[0018] Furthermore, the upper air sealing plate is provided with an assembly groove corresponding to the sealing protrusion, and the sealing protrusion is clearance-matched with the assembly groove.

[0019] Furthermore, the sealing protrusion is provided with a first groove corresponding to the sealing strip, and the upper air sealing plate is provided with a second groove corresponding to the sealing strip, and the second groove is extended in the assembly groove.

[0020] By adopting the above technical solution, the sealing protrusion is sealed with the upper air sealing plate on the one hand, and on the other hand, the installation positioning between the upper air sealing plate and the lower air sealing plate is realized, and the sealing strips arranged in the first slot and the second slot are cooperated to ensure the sealing effect between the upper air sealing plate and the lower air sealing plate.

[0021] Furthermore, the gap between the top of the central tube and the bottom of the upper air sealing plate is less than 2 mm.

[0022] By adopting the above technical solution, the gap between the top of the center tube and the bottom of the upper air sealing plate in the prior art is 6 mm. The current setting of the sealing protrusion can effectively reduce the gap between the top of the center tube and the bottom of the upper air sealing plate, thereby ensuring the partition effect inside and outside the center tube and avoiding gas disturbance.

[0023] In summary, the technical solution of the utility model has the following advantages:

[0024] 1. The optical fiber drawing furnace assembly structure provided by the utility model is provided with a sealing protrusion which is embedded and matched with the upper air sealing plate. Even if the central tube is expanded by heat and pushes out the upper air sealing plate upward, the upper air sealing plate and the lower air sealing plate can be effectively sealed to prevent the infiltration of outside air and cause gas disturbance.

[0025] 2. The optical fiber drawing furnace assembly structure provided by the utility model has a sealing protrusion that, on the one hand, cooperates with the upper air sealing plate for sealing, and on the other hand, realizes the installation positioning between the upper air sealing plate and the lower air sealing plate, and cooperates with the sealing strips arranged in the first slot and the second slot to ensure the sealing effect between the upper air sealing plate and the lower air sealing plate.

[0026] 3. The optical fiber drawing furnace assembly structure provided by the utility model can effectively reduce the gap between the top of the central tube and the bottom of the upper gas sealing plate by using the current sealing protrusion setting, thereby ensuring the partition effect between the inside and outside of the central tube and avoiding gas disturbance. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 It is a cross-sectional structural schematic diagram of the assembly structure of an optical fiber drawing furnace in the prior art;

[0029] Figure 2 It is a schematic diagram of the overall structure of an optical fiber drawing furnace assembly structure provided in one embodiment of the utility model;

[0030] Figure 3 A schematic cross-sectional view of an optical fiber drawing furnace assembly structure provided in one embodiment of the utility model;

[0031] Figure 4 for Figure 3 Schematic diagram of the enlarged structure of part A in the middle.

[0032] Description of reference numerals:

[0033] 1. Upper air sealing plate; 11. First through hole; 111. First stepped groove; 12. Ventilation hole; 121. Ventilation chamber; 13. Ventilation device; 14. Upper cooling chamber; 141. Upper inlet and outlet; 15. Snap ring; 16. Assembly groove; 161. Second slot; 2. Lower air sealing plate; 21. Second through hole; 211. Second stepped groove; 22. Lower cooling chamber; 221. Lower inlet and outlet; 3. Center tube; 4. Fixing piece; 41. Locking bolt; 42. Countersunk hole; 43. Compression spring; 5. Sealing piece; 51. Sealing protrusion; 511. First slot; 52. Sealing strip. DETAILED DESCRIPTION

[0034] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0035] An optical fiber drawing furnace assembly structure, such as Figure 1 As shown, it includes an upper air sealing plate 1, a lower air sealing plate 2 and a central tube 3. A coaxial central tube 3 is arranged in the lower air sealing plate 2. A gap is left between the top of the central tube 3 and the bottom of the upper air sealing plate 1. The gap is reserved for the expansion gap of the central tube 3 and the gap distance is greater than 6 mm.

[0036] like Figure 2 , Figure 3 and Figure 4As shown, it includes an upper gas sealing plate 1, a lower gas sealing plate 2 and a central tube 3, and also includes a fixing member 4 and a sealing member 5. The gap between the top of the central tube 3 and the bottom of the upper gas sealing plate 1 is less than 2 mm. The current setting of the sealing protrusion 51 can effectively reduce the gap between the top of the central tube 3 and the bottom of the upper gas sealing plate 1, thereby ensuring the isolation effect inside and outside the central tube 3 and avoiding gas disturbance; when the central tube 3 and the upper gas sealing plate 1 are assembled, accurate positioning is ensured while improving the assembly fault tolerance.

[0037] The fixing member 4 includes a locking bolt 41, a countersunk hole 42 and a compression spring. The countersunk hole 42 is provided on the upper air sealing plate 1. The compression spring 43 is sleeved on the locking bolt 41. The locking bolt 41 passes through the countersunk hole 42 and is fixed to the lower air sealing plate 2. After the center tube 3 expands, it pushes against the upper air sealing plate 1. Since the upper air sealing plate 1 is fixed by the fixing member 4 and cooperates with the compression spring 43, the upper air sealing plate 1 will not be pushed open, causing the outside air to enter.

[0038] The sealing member 5 is arranged between the upper air-sealing plate 1 and the lower air-sealing plate 2. The sealing member 5 includes a sealing protrusion 51 and a plurality of sealing clips 52. The sealing protrusion 51 is arranged integrally with the lower air-sealing plate 2 and is extended to the top of the lower air-sealing plate 2. The upper air-sealing plate 1 is provided with a mounting groove 16 corresponding to the sealing protrusion 51. The sealing clips 52 are arranged between the sealing protrusion 51 and the upper air-sealing plate 1. The sealing protrusion 51 is arranged to be embedded and matched with the upper air-sealing plate 1, so that during the overall assembly, the upper air-sealing plate 1 and the lower air-sealing plate 2 are closely matched, the gap between the top of the central tube 3 and the upper air-sealing plate 1 can be effectively reduced, and even if the central tube 3 is heated and expanded and pushes out of the upper air-sealing plate 1, the upper air-sealing plate 1 and the lower air-sealing plate 2 can be effectively sealed to prevent the infiltration of external air and cause gas disturbance.

[0039] like Figure 3 and Figure 4 As shown, the upper air sealing plate 1 has a first through hole 11 extending through the center, and a first stepped groove 111 extending from the top of the first through hole 11 to the side away from the axis. The lower air sealing plate 2 has a second through hole 21 extending through the center, and the diameter of the second through hole 21 is larger than the diameter of the first through hole 11. A second stepped groove 211 extends from the upper half of the second through hole 21 to the side away from the axis. The existence of the first through hole 11 and the second through hole 21 facilitates the placement of the central tube 3. The provision of the first stepped groove 111 and the second stepped groove 211 can effectively increase the length of the air circulation path, thereby reducing the possibility of air infiltration and ensuring the sealing effect.

[0040] like Figure 2 and Figure 3As shown, the inner wall of the upper air sealing plate 1 is also provided with a plurality of vent holes 12 in a circumferential array, and an annular ventilation chamber 121 is provided at one end of the vent hole 12 away from the first through hole 11, one end of the vent hole 12 is connected to the first through hole 11, and the other end is connected to the ventilation chamber 121, and the ventilation chamber 121 is connected to all the vent holes 12, and a ventilation device 13 is also connected to one side of the upper air sealing plate 1, and the ventilation device 13 is connected to the ventilation chamber 121. The ventilation device 13 is connected to the ventilation cavity so as to ventilate the interior of the upper air sealing plate 1 through the vent holes 12, so as to realize the air sealing operation inside the upper air sealing plate 1.

[0041] An upper cooling chamber 14 is provided along the circumference in the upper air sealing plate 1, and an upper inlet and outlet 141 communicating with the upper cooling chamber 14 is provided on the side wall of the upper air sealing plate 1. A lower cooling chamber 22 is provided along the circumference in the lower air sealing plate 2, and a lower inlet and outlet 221 communicating with the lower cooling chamber 22 is provided on the side wall of the lower air sealing plate 2. The upper cooling chamber 14 and the lower cooling chamber 22 are provided to dissipate the heat generated during the operation of the optical fiber drawing furnace, and coolant is circulated through the upper inlet and outlet 141 and the lower inlet and outlet 221, and the coolant includes but is not limited to water.

[0042] like Figure 3 and Figure 4 As shown, a snap ring 15 extends from the bottom of the upper air sealing plate 1, and the snap ring 15 is snapped with the top of the lower air sealing plate 2, and the outer diameter of the snap ring 15 is equal to the inner diameter of the second stepped groove 211. The snap ring 15 is snapped into the second stepped groove 211 to ensure that the upper air sealing plate 1 can still be connected to the lower air sealing plate 2 even if it is pushed out by the expansion of the central tube 3, reducing the entry of external air and ensuring that the upper air sealing plate 1 and the lower air sealing plate 2 are tightly connected.

[0043] The sealing protrusion 51 is provided with a first card groove 511 corresponding to the sealing card strip 52, and the upper air sealing plate 1 is provided with a second card groove 161 corresponding to the sealing card strip 52, and the second card groove 161 is extended and arranged in the assembly groove 16. The sealing protrusion 51 is sealed with the upper air sealing plate 1 on the one hand, and realizes the installation and positioning between the upper air sealing plate 1 and the lower air sealing plate 2 on the other hand, and cooperates with the sealing card strip 52 arranged in the first card groove 511 and the second card groove 161 to ensure the sealing effect between the upper air sealing plate 1 and the lower air sealing plate 2, so as to ensure the stability of the temperature field of the light rod in the central tube 3 during the high-temperature wire drawing process.

[0044] The working principle and use method of the optical fiber drawing furnace assembly structure are as follows: In order to reduce the gap between the central tube 3 and the upper air sealing plate 1 and ensure that the central tube 3 will not push out of the upper air sealing plate 1 after expansion, a sealing protrusion 51 is arranged on the top of the upper air sealing plate 1, and the sealing protrusion 51 is intermittently matched with the assembly groove 16; a sealing strip 52 is also arranged in the assembly groove 16 to increase the sealing performance and prevent the infiltration of outside air from causing gas disturbance inside and outside the central tube 3.

[0045] The above description shows and describes the preferred embodiments of the utility model. As mentioned above, it should be understood that the utility model is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the utility model concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not depart from the spirit and scope of the utility model, and should be within the scope of protection of the claims attached to the utility model.

Claims

1. An optical fiber drawing furnace assembly structure, comprising an upper gas sealing plate (1), a lower gas sealing plate (2) and a central tube (3), wherein a coaxial central tube (3) is arranged in the lower gas sealing plate (2), and a gap is left between the top of the central tube (3) and the bottom of the upper gas sealing plate (1), characterized in that: Also includes: A fixing member (4), the fixing member (4) comprising a locking bolt (41), a recessed hole (42) and a compression spring (43), the recessed hole (42) being formed on the upper air sealing plate (1), the compression spring (43) being sleeved on the locking bolt (41), and the locking bolt (41) passing through the recessed hole (42) and being fixed on the lower air sealing plate (2); A sealing member (5), wherein the sealing member (5) is arranged between an upper air-sealing plate (1) and a lower air-sealing plate (2), and the sealing member (5) comprises a sealing protrusion (51) and a plurality of sealing clips (52), wherein the sealing protrusion (51) is integrally arranged with the lower air-sealing plate (2) and extends to the top of the lower air-sealing plate (2), and the sealing clips (52) are all arranged between the sealing protrusion (51) and the upper air-sealing plate (1).

2. The optical fiber drawing furnace assembly structure according to claim 1, characterized in that: A first through hole (11) is provided through the center of the upper air sealing plate (1), a first stepped groove (111) is extended from the top of the first through hole (11), a second through hole (21) is provided through the center of the lower air sealing plate (2), a diameter of the second through hole (21) is larger than a diameter of the first through hole (11), and a second stepped groove (211) is extended near the top of the second through hole (21).

3. The optical fiber drawing furnace assembly structure according to claim 2, characterized in that: The upper air sealing plate (1) is also provided with a plurality of ventilation holes (12) in a circumferential array, and a ventilation chamber (121) is provided at one end of the ventilation hole (12) away from the first through hole (11); one end of the ventilation hole (12) is connected to the first through hole (11), and the other end is connected to the ventilation chamber (121); the upper air sealing plate (1) is also connected to a ventilation device (13), and the ventilation device (13) is connected to the ventilation chamber (121).

4. The optical fiber drawing furnace assembly structure according to claim 3, characterized in that: An upper cooling chamber (14) is circumferentially opened in the upper air sealing plate (1), and an upper inlet and outlet (141) communicating with the upper cooling chamber (14) is provided on a side wall of the upper air sealing plate (1); a lower cooling chamber (22) is circumferentially opened in the lower air sealing plate (2), and a lower inlet and outlet (221) communicating with the lower cooling chamber (22) is provided on a side wall of the lower air sealing plate (2).

5. The optical fiber drawing furnace assembly structure according to claim 4, characterized in that: A snap ring (15) extends from the bottom of the upper air sealing plate (1), the snap ring (15) is snap-fitted to the top of the lower air sealing plate (2), and the outer diameter of the snap ring (15) is equal to the inner diameter of the second stepped groove (211).

6. The optical fiber drawing furnace assembly structure according to claim 5, characterized in that: The upper air sealing plate (1) is provided with an assembly groove (16) corresponding to the sealing protrusion (51), and the sealing protrusion (51) and the assembly groove (16) are clearance-matched.

7. The optical fiber drawing furnace assembly structure according to claim 6, characterized in that: The sealing protrusion (51) is provided with a first slot (511) corresponding to the sealing clip strip (52), and the upper air sealing plate (1) is provided with a second slot (161) corresponding to the sealing clip strip (52), and the second slot (161) is extended and arranged in the assembly slot (16).

8. The optical fiber drawing furnace assembly structure according to claim 1, characterized in that: The gap between the top of the central tube (3) and the bottom of the upper air sealing plate (1) is less than 2 mm.

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