Carbon fiber stretching device

Abstract

The present application relates to a kind of carbon fiber stretching treatment device, including temperature gradient unit, temperature gradient unit includes temperature regulating cone cylinder, heating coil is equipped in the narrow end side wall of the temperature regulating cone cylinder, the small head center of the temperature regulating cone cylinder is equipped with second traction wheel, the big head center of the temperature regulating cone cylinder is equipped with first traction wheel, and the distribution radius of first traction wheel and second traction wheel is same.The temperature regulating cone cylinder of tapered cylinder design in the present application can make the temperature of fiber silk gradually change, by adjusting the distance of fiber silk to heating coil, i.e.through adjusting the distance of heat radiation to realize the adjustment of temperature gradient, prevent the internal stress change of carbon fiber due to temperature mutation, affect the quality of carbon fiber stretching forming.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of carbon fibers, and particularly relates to a carbon fiber stretching treatment device. BACKGROUND

[0002] In the carbon fiber drawing process, temperature control is very critical. Specifically, the control of preheating temperature, carbonization temperature and drawing temperature. The preheating temperature is generally controlled at about 300 DEG C, the carbonization temperature is about 2000 DEG C, and the drawing temperature is controlled at about 1200 DEG C. In the drawing process, the temperature rising speed needs to be controlled to avoid fiber breakage or collapse caused by too fast rising.

[0003] Especially in the heat treatment and carbonization process, the temperature rising speed of the carbon fiber filament surface must be controlled, and cannot be too fast to achieve uniform rising. If the temperature fluctuates too fast, stress is easily generated in the fiber during thermal expansion and cold contraction, leading to breakage or even collapse. Therefore, during the adjustment from the preheating temperature to the carbonization temperature, the temperature needs to be slowly raised, and when adjusted to the drawing temperature, the temperature needs to be slowly lowered. Each time the temperature changes greatly, the change speed is slow, and the overall temperature change waiting time is long. SUMMARY

[0004] In view of the above problems, the present application provides a carbon fiber stretching treatment device to at least partially solve the above problems.

[0005] The technical scheme adopted by the present application is as follows: the present application provides a carbon fiber stretching treatment device, which comprises a temperature gradient unit, which is arranged in a preheating process, a carbonization process and a drawing process respectively. The number of temperature gradient units in each process can be adjusted as needed. The directions of the temperature gradient units at the front end and the rear end of the drawing process are completely opposite.

[0006] Further, in order to convey the carbon fiber filament into each temperature gradient unit, a conveying system is arranged between each temperature gradient unit.

[0007] Further, the conveying system comprises a feeding roller, a transition roller, a drawing roller and a recovery roller. The feeding roller is arranged in front of the temperature gradient unit in the preheating stage. The transition roller is arranged between the temperature gradient units in the carbonization and drawing stages. The drawing roller is arranged at the rear end of the temperature gradient unit in the drawing stage. The recovery roller is arranged behind the drawing roller.

[0008] Further, the temperature gradient unit comprises a temperature adjusting cone, a heating coil is arranged in the narrow end side wall of the temperature adjusting cone, a second traction wheel is arranged at the center of the small head of the temperature adjusting cone, and a first traction wheel is arranged at the center of the large head of the temperature adjusting cone. The distribution radius of the first traction wheel and the second traction wheel is the same.

[0009] Further, in order to make the distribution radius of the first traction wheel and the second traction wheel same, the large end of the temperature adjusting cone is provided with a centering support, the inner diameter of the centering support is same with the inner diameter of the small end of the temperature adjusting cone, and the first traction wheel is fixed on the centering support.

[0010] Further, the sidewall of the temperature adjusting cone is provided with a heating cavity, and the heating coil is arranged in the heating cavity and close to the small end;

[0011] Further, in order to make the front and rear temperature adjusting cones be able to be sealed in series, the sidewall of the small end of the temperature adjusting cone is provided with an alignment flange.

[0012] Further, in order to monitor and actively intervene the temperature change trend in each group of temperature gradient units, the middle and lower section of the heating cavity is provided with a lower temperature adjusting groove, and the upper end of the heating cavity is provided with an upper temperature adjusting groove;

[0013] Further, the upper temperature adjusting groove is communicated with an air outlet ring, the air outlet ring is provided with an air outlet end adjusting valve, and the temperature adjusting cone close to the upper temperature adjusting groove is provided with an air outlet end sensor communicated with the heating cavity;

[0014] Further, the lower temperature adjusting groove is communicated with an air inlet ring, the air inlet ring is provided with an air inlet end adjusting valve, and the temperature adjusting cone close to the small end is provided with an air inlet end sensor communicated with the heating cavity.

[0015] Further, in order to improve the energy utilization efficiency, a heat collecting cylinder is arranged above the temperature gradient units, the heat collecting cylinder is connected with the air outlet rings on the temperature gradient units, and the temperature and heat in the heating cavity of the temperature adjusting cone are transported to the heat collecting cylinder through the air outlet rings;

[0016] Further, because the exhaust gas temperature in each process temperature gradient unit is different, in order to facilitate the control of the temperature of the resin drying process, the end of the heat collecting cylinder is provided with a heat equalizing cylinder, the heat equalizing cylinder is rotatably provided with stirring blades, and the shaft end of the stirring blades is connected with a motor.

[0017] Further, the lower end of the heat equalizing cylinder is connected with a resin oven, and the resin oven is provided with a resin immersion roller for guiding the carbon fiber wire.

[0018] The beneficial effects obtained by the present application are as follows: the temperature adjusting cone with the taper cylinder design of the temperature gradient unit can make the temperature of the fiber wire gradually change, the distance of the fiber wire to the heating coil in the temperature gradient unit is adjusted, that is, the distance of the heat radiation is adjusted to realize the adjustment of the temperature gradient, the internal stress change of the carbon fiber caused by the temperature mutation is prevented, the quality of the carbon fiber stretch forming is affected, the overall temperature change is divided into each stage, a certain amount of temperature adjustment is completed by each temperature adjusting cone, the temperature difference of the overall temperature adjustment is reduced, and the temperature control efficiency is improved. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a partial sectional view of the structural schematic diagram of the embodiment of the present application;

[0020] Figure 2 is a partial sectional view of the structural schematic diagram of the embodiment of the present application; Figure 1 is an enlarged view of part I;

[0021] Figure 3 is a sectional view of the temperature gradient unit;

[0022] Figure 4 is an isometric side view of the temperature gradient unit;

[0023] Figure 5 is a sectional view of the temperature adjusting cone;

[0024] Figure 6 is a temperature change diagram of the carbon fiber filament in the temperature gradient unit at each stage.

[0025] Wherein, 1, temperature gradient unit, 2, conveying system, 2-1, feeding roller, 2-2, transition roller, 2-3, stretching roller, 2-4, recovery roller, 3, heat collecting cylinder, 4, resin oven, 5, soaking cylinder, 6, motor, 7, stirring blade, 8, impregnation roller, 9, temperature adjusting cone, 10, first traction wheel, 11, second traction wheel, 12, air outlet ring, 13, air inlet ring, 14, air outlet end regulating valve, 15, air inlet end regulating valve, 16, air outlet end sensor, 17, air inlet end sensor, 18, heating coil, 19, centering support, 20, heating cavity, 21, lower temperature adjusting groove, 22, upper temperature adjusting groove, 23, alignment flange.

[0026] In the accompanying drawings, Figure 6 In the accompanying drawings, T1, T2, T3, T4, T5 and T6 respectively represent the temperature of the carbon fiber at different stages.

[0027] The accompanying drawings are used to provide a further understanding of the present application, and constitute a part of the specification, together with the embodiments of the present application, to explain the present application, and do not constitute a limitation on the present application. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0029] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0030] As Figure 1 shown, the carbon fiber stretching treatment device provided by the embodiment of the present application comprises temperature gradient units 1, which are respectively arranged in preheating, carbonization and stretching processes. The number of temperature gradient units 1 in each process can be adjusted as needed. The more the number of temperature gradient units 1, the more moderate the temperature rising curve, and the larger the temperature span of the carbonization and stretching processes. A plurality of temperature gradient units 1 can be connected in series to achieve slow temperature change. The directions of the temperature gradient units 1 at the front end and the rear end of the stretching process are completely opposite. The temperature of the fiber yarn in the temperature gradient unit 1 at the front end of the stretching process gradually rises, and the temperature of the fiber yarn in the temperature gradient unit 1 at the rear end of the stretching process gradually decreases.

[0031] In order to convey the carbon fiber yarn into each temperature gradient unit 1, a conveying system 2 is arranged between each temperature gradient unit 1;

[0032] The conveying system 2 comprises a feeding roller 2-1, a transition roller 2-2, a stretching roller 2-3 and a recovery roller 2-4. The feeding roller 2-1 is arranged in front of the temperature gradient unit 1 in the preheating stage, and the feeding roller 2-1 conveys the material into the first group of temperature gradient units 1 for preheating. In this embodiment, the cross section of the temperature gradient unit 1 is circular. In order to make the carbon fiber smoothly and smoothly gathered into the temperature gradient unit 1, a deflection wheel set (not shown in the drawings) can be added at the rear end of the feeding roller 2-1 to change the conveying angle of the carbon fiber and prevent the carbon fiber from bending at a large angle. The transition roller 2-2 is arranged between the temperature gradient units 1 in the carbonization and stretching stages, which is used to buffer the carbonization process and prepare for the next stretching process. The stretching roller 2-3 is arranged at the rear end of the temperature gradient unit 1 in the stretching stage. After the heat treatment of the carbon fiber is completed, the stretching roller 2-3 applies a certain tension to the carbon fiber. The recovery roller 2-4 is arranged behind the stretching roller 2-3, which is used to wind the processed carbon fiber.

[0033] As Figure 3 and Figure 4As shown, the temperature gradient unit 1 includes a temperature adjustment cone 9, a heating coil 18 is arranged in the narrow end side wall of the temperature adjustment cone 9, and the heating coil 18 generates heat after being electrified, thereby heating the temperature adjustment cone 9. After the temperature adjustment cone 9 generates heat, the heat will be radiated to the carbon fiber, thereby heating and treating the carbon fiber. The small head center of the temperature adjustment cone 9 is provided with a second traction wheel 11, and the large head center of the temperature adjustment cone 9 is provided with a first traction wheel 10. The distribution radius of the first traction wheel 10 and the second traction wheel 11 is the same. Because the distance between the first traction wheel 10 and the second traction wheel 11 and the central axis of the temperature adjustment cone 9 is the same, the distance between the carbon fiber on the first traction wheel 10 and the second traction wheel 11 and the side wall of the temperature adjustment cone 9 changes linearly. By adjusting the distance between the fiber and the radiation heat source, the temperature gradient adjustment is realized, and the change of the internal stress of the carbon fiber caused by the sudden change of the temperature is prevented, thereby affecting the quality of the carbon fiber stretch forming.

[0034] In order to make the distribution radius of the first traction wheel 10 and the second traction wheel 11 the same, the large head end of the temperature adjustment cone 9 is provided with a centering support 19, the inner diameter of the centering support 19 is the same as the inner diameter of the small head end of the temperature adjustment cone 9, and the first traction wheel 10 is fixed on the centering support 19.

[0035] As shown in Figure 5 The side wall of the temperature adjustment cone 9 is provided with a heating cavity 20, the heating coil 18 is arranged in the heating cavity 20 close to the small head, and the temperature of the far end of the heating cavity 20 from the heating coil 18 is lower than that of the heating coil 18. Therefore, in the horizontal direction (i.e. the central axis direction of the temperature adjustment cone 9) and the vertical direction, the heat and temperature in the temperature adjustment cone 9 change gradually. For details, refer to Figure 6 In the preheating process, the temperature of the large head end of the temperature adjustment cone 9 is T1, and the temperature of the small head end is T2. T2 is greater than T1. In the carbonization process, the temperature of the large head end of the temperature adjustment cone 9 is T3, and the temperature of the small head end is T4. T4 is greater than T3, and T3 is approximately equal to T2. When the carbon fiber enters the stretching process, the direction of the temperature adjustment cone 9 is adjusted. The temperature of the small head end of the temperature adjustment cone 9 is T5, and the temperature of the large head end is T6. T5 is greater than T6. If the temperature span is large during the stretching process, a plurality of temperature gradient units 1 are arranged at this time. The temperature of the small head end of the temperature adjustment cone 9 in the subsequent temperature gradient unit 1 is T7, and the temperature of the large head end is T8. T7 is greater than T8, and T6 is approximately equal to T7. If the number of temperature gradient units 1 is increased subsequently, the temperature change is the same. The more the number of temperature gradient units 1, the more moderate the temperature change curve is.

[0036] In order to make the front and rear temperature adjustment cones 9 be able to be sealed in series, the small head end side wall of the temperature adjustment cone 9 is provided with an alignment flange 23.

[0037] In order to monitor and actively intervene in the temperature change trend in each group of temperature gradient units 1, refer toFigure 3 and Figure 4 The middle and lower section of the heating cavity 20 is provided with a lower temperature adjusting groove 21, and the upper end of the heating cavity 20 is provided with an upper temperature adjusting groove 22;

[0038] The upper temperature adjusting groove 22 is communicated with an air outlet ring 12, and the air outlet ring 12 is provided with an air outlet end adjusting valve 14. The temperature adjusting cone cylinder 9 is provided with an air inlet end sensor 16 communicated with the heating cavity 20 near the upper temperature adjusting groove 22.

[0039] The lower temperature adjusting groove 21 is communicated with an air inlet ring 13, and the air inlet ring 13 is provided with an air inlet end adjusting valve 15. The temperature adjusting cone cylinder 9 is provided with an air inlet end sensor 17 communicated with the heating cavity 20 near the small end. The air inlet ring 13 can be communicated with temperature adjusting gas, specifically hot gas or cold gas can be communicated according to needs. The air outlet end sensor 16 and the air inlet end sensor 17 at both ends of the temperature adjusting cone cylinder 9 respectively sense the temperature at the highest and lowest points to monitor the temperature difference in the temperature adjusting cone cylinder 9, so as to prevent the temperature from rising and falling greatly. When the temperature difference at both ends of the temperature adjusting cone cylinder 9 is not within the control range, the air outlet end adjusting valve 14 or the air inlet end adjusting valve 15 can be adjusted, or both can be adjusted to adjust the flow of gas, so as to adjust the internal temperature difference.

[0040] As shown in Figure 1 and Figure 2 In order to improve the energy utilization efficiency, a heat collecting cylinder 3 is arranged above the temperature gradient unit 1. The heat collecting cylinder 3 is connected with the air outlet ring 12 on each temperature gradient unit 1. The temperature and heat in the heating cavity 20 of the temperature adjusting cone cylinder 9 are transported to the heat collecting cylinder 3 by the air outlet ring 12 to provide heat energy for the subsequent drying process of the carbon fiber impregnated resin.

[0041] Because the temperature of the gas discharged from each temperature gradient unit 1 is different, in order to facilitate the control of the temperature of the resin drying process, the end of the heat collecting cylinder 3 is provided with a heat equalizing cylinder 5. The heat equalizing cylinder 5 is rotatably provided with stirring blades 7. The shaft end of the stirring blades 7 is connected with a motor 6. The motor 6 drives the stirring blades 7 to rotate to uniformly distribute the temperature of the gas in the heat collecting cylinder 3.

[0042] The lower end of the heat equalizing cylinder 5 is connected with a resin oven 4. An adjusting valve (not shown in the drawings) can be optionally arranged at the connecting pipe of the two to control the heat in the resin oven 4. The resin oven 4 is provided with a resin impregnation roller 8 for guiding the carbon fiber yarn.

[0043] In specific work, the carbon fiber yarn is wound on the feeding roller 2-1, and cooperates with the auxiliary of the deflection wheel set to make the carbon fiber yarn wound on the first traction wheel 10 and the second traction wheel 11 in the temperature gradient unit 1 in the preheating process, that is, the originally flat and unfolded carbon fiber yarn is changed into a bundled shape. The carbon fiber yarn is continuously passed through the temperature gradient unit in the carbonization and stretching process, and is wound on the transition roller 2-2, the stretching roller 2-3 and the recovery roller 2-4.

[0044] The rollers in the conveying system 2 rotate under the action of external power, and the carbon fiber yarn will pass through the center of each temperature gradient unit 1 in turn. The heating coil 18 in each temperature gradient unit 1 is started, the heating coil 18 is rapidly heated, and heat is radiated outward, so that the temperature inside the temperature adjusting cone cylinder 9 is increased. The temperature inside the temperature adjusting cone cylinder 9 will gradually change in the horizontal direction (i.e. the central axis direction of the temperature adjusting cone cylinder 9) and the vertical direction.

[0045] When the carbon fiber yarn enters the temperature adjusting cone cylinder 9 in the preheating process, the temperature on the surface of the carbon fiber yarn gradually increases from the low temperature at the large end to the high temperature at the small end. When passing through the aligned flange 23, it enters the next carbonization process and continues to repeat the temperature increasing action of the previous process until the temperature reaches the requirement of each process. The slow temperature increasing curvature can be achieved by increasing or decreasing the number of temperature adjusting cone cylinders 9, which will not be repeated here.

[0046] After the carbonization of the carbon fiber yarn is completed, the temperature needs to be lowered for stretching treatment. The carbon fiber is conveyed by the transition roller 2-2 to the temperature gradient unit 1 where the stretching process is located. At this time, cold air can be introduced into the air outlet ring 12 on the current temperature adjusting cone cylinder 9 in the opposite direction. The cold air absorbs heat from the surrounding, so that the temperature of the carbon fiber yarn in the temperature adjusting cone cylinder 9 changes slowly. If necessary, the heating coil 18 can be turned on to assist temperature adjustment. When the carbon fiber yarn passes through all the temperature adjusting cone cylinders 9 and the temperature reaches the set value, the stretching roller 2-3 stretches and shapes the carbon fiber yarn.

[0047] During the above operation process, if it is necessary to actively intervene in the temperature difference in each temperature adjusting cone cylinder 9, the monitoring of the outlet end sensor 16 and the inlet end sensor 17 can determine whether the current temperature difference range is within the controllable range. If it is out of the control range, the outlet end adjusting valve 14, the inlet end adjusting valve 15, or both can be adjusted.

[0048] After the stretching of the carbon fiber yarn is completed, it is continuously pulled by the recovery roller 2-4 to the resin oven 4 for resin impregnation. The high temperature gas discharged from the temperature adjusting cone cylinder 9 is also recovered to the heat equalizing cylinder 5 by the heat collecting cylinder 3. The motor 6 drives the stirring blade 7 to stir the gas at different temperatures in the heat equalizing cylinder 5 uniformly, so that the internal temperature is consistent. If the temperature is too high, the temperature can be controlled by adjusting the valve.

[0049] The adjusted temperature gas is introduced into the resin oven 4 for baking treatment of the carbon fiber which has just been impregnated with resin, and finally is wound by the recovery roller 2-4.

[0050] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting; thus the use of any

[0051] The above description of the application and its embodiments is not restrictive, and the embodiments shown in the drawings are only one of the embodiments of the application, and the actual structure is not limited thereto. In general, if a person skilled in the art is inspired by it, without departing from the purpose of the application, without creative design, similar structure and embodiments of the technical solution can be designed, which should belong to the protection scope of the application.

Claims

1. A carbon fiber stretching treatment apparatus characterized by comprising: The application relates to a temperature gradient unit (1) arranged in each of preheating, carbonization and stretching stages, the number of the temperature gradient units (1) in each stage is adjustable, and the temperature gradient units (1) at the front end and the rear end of stretching are opposite in direction; a conveying system (2) is arranged between the temperature gradient units (1) and used for conveying carbon fiber filaments; wherein the temperature gradient unit (1) comprises a temperature adjusting cone (9), a heating coil (18) is arranged in the narrow end sidewall of the temperature adjusting cone (9), a second traction wheel (11) is arranged at the center of the small head of the temperature adjusting cone (9), a first traction wheel (10) is arranged at the center of the large head of the temperature adjusting cone (9), and the distribution radii of the first traction wheel (10) and the second traction wheel (11) are the same; a heating cavity (20) is arranged in the sidewall of the temperature adjusting cone (9), the heating coil (18) is arranged at one end of the heating cavity (20) close to the small head, a lower temperature adjusting groove (21) is arranged at the middle lower section of the heating cavity (20), and an upper temperature adjusting groove (22) is arranged at the upper end of the heating cavity (20); an air outlet ring (12) is connected to the upper temperature adjusting groove (22), an air outlet end adjusting valve (14) is arranged on the air outlet ring (12), and an air outlet end sensor (16) connected to the heating cavity (20) is arranged on the temperature adjusting cone (9) close to the upper temperature adjusting groove (22); an air inlet ring (13) is connected to the lower temperature adjusting groove (21), an air inlet end adjusting valve (15) is arranged on the air inlet ring (13), and an air inlet end sensor (17) connected to the heating cavity (20) is arranged on the temperature adjusting cone (9) close to the small head end; and a flange (23) is arranged on the sidewall of the small head end of the temperature adjusting cone (9). A heat collecting cylinder (3) is connected to each temperature gradient unit (1), the end of the heat collecting cylinder (3) is provided with a heat equalizing cylinder (5), stirring blades (7) are arranged in the heat equalizing cylinder (5) and rotate, and the shaft ends of the stirring blades (7) are connected with motors (6). The lower end of the heat equalizing cylinder (5) is connected with a resin oven (4), and the resin oven (4) is provided with a resin immersion roller (8). The conveying system (2) comprises a feeding roller (2-1), a transition roller (2-2), a stretching roller (2-3) and a recovery roller (2-4), the feeding roller (2-1) is arranged in front of the temperature gradient unit (1) in the preheating stage, the transition roller (2-2) is arranged between the temperature gradient units (1) in the carbonization and stretching stages, the stretching roller (2-3) is arranged at the rear end of the temperature gradient unit (1) in the stretching stage, and the recovery roller (2-4) is arranged behind the stretching roller (2-3). The large head end of the temperature adjusting cone (9) is provided with a centering support (19), the inner diameter of the centering support (19) is the same as that of the small head end of the temperature adjusting cone (9), and the first traction wheel (10) is fixed on the centering support (19). ​ ​ ​ 2. The carbon fiber stretch treatment device according to claim 1, characterized by: ​ 3. The carbon fiber stretch treatment device according to claim 2, characterized by: ​ 4. The carbon fiber stretch treatment device according to claim 1, characterized by: ​ 5. The carbon fiber stretch treatment device according to claim 1, characterized by: ​

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