Infrared drying apparatus for carbon fiber production

Abstract

The utility model relates to carbon fiber manufacturing technical field discloses an infrared drying equipment for carbon fiber production, including heating module, temperature measurement module, control module, reflection module, exhaust module, wherein, heating module includes infrared radiation source, temperature measurement module includes infrared temperature measurement unit, imaging unit, correction unit. The utility model adopts non -contact infrared temperature measurement unit, avoids the temperature deviation of traditional contact type temperature measurement element measurement equipment in hot air temperature, obtains the infrared drying equipment cavity image through imaging unit simultaneously, further corrects the temperature deviation of infrared radiation that reflection board reflects in correction unit, accurately measures the surface temperature of tow, adjusts and controls infrared radiation source power, accurately control carbon fiber tow surface temperature, reduces carbon fiber CV value.

Description

Technical Field

[0001] This utility model belongs to the field of carbon fiber manufacturing technology, and more specifically, it relates to an infrared drying device for carbon fiber production. Background Technology

[0002] In the production process of carbon fiber, multiple drying processes are required. The heating method, heat distribution, and temperature control sensitivity of the carbon fiber tow directly affect the final quality of the carbon fiber. Currently, carbon fiber production lines mainly use hot air circulating drying equipment to dry the carbon fiber, with thermocouple sensors to detect the temperature inside the equipment and a controller to regulate the temperature. On the one hand, traditional hot air circulating drying equipment suffers from uneven heating between the surface and interior of the carbon fiber tow, resulting in uneven drying. On the other hand, thermocouple sensors cannot directly contact the carbon fiber tow, otherwise it will cause the carbon fiber tow to become fuzzy and break. Therefore, using traditional contact temperature sensing elements can only measure the temperature of the hot air inside the equipment, and cannot actually measure the process temperature on the surface of the carbon fiber tow, resulting in significant differences in the measured temperature at different measuring points.

[0003] CN221882088U combines infrared drying, hot air drying, and electric drying to achieve uniform moisture evaporation inside and outside the carbon fiber bundle, avoiding local temperature accumulation and achieving uniform drying. However, this patent does not mention the temperature detection and control methods in the drying equipment.

[0004] Therefore, how to design a device that can precisely control the surface temperature of carbon fiber bundles and achieve uniform drying inside and on the surface of carbon fiber bundles has become a technical problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0005] To address the shortcomings of existing technologies, this invention proposes an infrared drying device for carbon fiber production, which enables both the surface and interior of the carbon fiber bundle to reach high temperatures simultaneously, and precisely controls the surface temperature of the carbon fiber bundle during the drying process, thereby improving the uniformity and efficiency of carbon fiber drying.

[0006] According to a first aspect of this utility model, an infrared drying device for carbon fiber production is provided, comprising a cavity, a carbon fiber bundle channel, a heating module, a temperature measuring module, a reflection module, and an exhaust module disposed within the cavity, and a control module connected to the heating module and the temperature measuring module.

[0007] The carbon fiber bundle channel has a carbon fiber bundle inlet and a carbon fiber bundle outlet. The carbon fiber bundle is fed into the cavity from the carbon fiber bundle inlet and discharged from the cavity from the carbon fiber bundle outlet.

[0008] The heating module is located on the first side of the inner wall of the cavity. The heating module includes an infrared radiation source for emitting infrared radiation to the carbon fiber bundle channel to heat and dry the carbon fiber bundle in the carbon fiber bundle channel.

[0009] The reflection module is located on the second side of the inner wall of the cavity, with the first side opposite to the second side. The carbon fiber bundle channel is located between the heating module and the reflection module. The reflection module includes a reflector plate for reflecting infrared radiation emitted by the infrared radiation source.

[0010] The temperature measuring module is located on the first side of the inner wall of the cavity and is used to detect the temperature of the carbon fiber bundle surface.

[0011] The input terminal of the control module is connected to the temperature measurement module, and the output terminal of the control module is connected to the heating module. The control module controls the operation of the heating module according to the input of the temperature measurement module.

[0012] The exhaust module is located on the first side of the inner wall of the cavity and is used to exhaust the steam generated on the surface and inside of the carbon fiber bundles from the cavity.

[0013] Furthermore, the temperature measurement module includes an infrared temperature measurement unit and an imaging unit. The infrared temperature measurement unit is connected to the control module and is used to detect the temperature of the carbon fiber bundle surface. The imaging unit is connected to the control module and is used to capture an image of the carbon fiber bundle channel plane. The control module includes a correction unit, which is used to correct the interference of infrared radiation reflected by the reflection module on the infrared temperature measurement unit in order to obtain the actual surface temperature of the carbon fiber bundle.

[0014] Furthermore, the infrared temperature measurement unit includes an infrared temperature sensor, and the imaging unit includes a camera. The infrared temperature sensor receives infrared radiation emitted by the carbon fiber bundle and infrared radiation reflected by the reflection module and outputs temperature data to the correction unit of the control module. At the same time, the camera images the carbon fiber bundle channel and outputs the obtained image to the correction unit of the control module. Thus, the control module adjusts the power of the infrared radiation source according to the actual surface temperature of the obtained carbon fiber bundle.

[0015] Furthermore, the temperature measurement module includes at least one set of infrared temperature measurement units, which are evenly distributed along the length of the cavity and the carbon fiber bundle channel; each set of infrared temperature measurement units includes at least one temperature measurement point, which is evenly distributed along the width of the cavity; the distance between the infrared temperature measurement unit and the carbon fiber bundle is 200~400mm.

[0016] Furthermore, the temperature measurement module includes at least one imaging unit, which is located at the outlet of the carbon fiber bundle and is evenly distributed along the width direction of the cavity and the carbon fiber bundle channel; the distance between the imaging unit and the carbon fiber bundle is 150~200cm.

[0017] Furthermore, the temperature measurement module is an infrared thermal imager.

[0018] Furthermore, the reflector is a mirror-finished stainless steel reflector, and the distance between the reflector and the carbon fiber bundle is 100~200mm; the area of ​​the reflector is greater than or equal to the area of ​​the radiation region of the infrared radiation source.

[0019] Furthermore, the heating module includes multiple sets of infrared radiation sources, which are evenly distributed along the length of the cavity and the carbon fiber bundle channel.

[0020] Furthermore, the infrared radiation source is a combination of short-wave infrared radiation source and mid-wave infrared radiation source, with the short-wave infrared radiation source and mid-wave infrared radiation source arranged alternately along the width direction of the cavity and the carbon fiber bundle channel.

[0021] Furthermore, the heating module includes multiple heating zones, each of which includes at least one set of infrared radiation sources, and each heating zone is independently temperature-controlled.

[0022] The beneficial effects of this utility model include:

[0023] 1) The temperature measurement module of this utility model adopts a non-contact infrared temperature measurement unit, which can monitor the surface temperature of carbon fiber bundles in real time. This avoids the temperature deviation caused by the hot air temperature inside the equipment measured by traditional contact temperature measurement elements. Furthermore, by combining the image obtained by the imaging unit, the interference caused by the infrared radiation reflected by the reflection module onto the infrared temperature measurement unit is corrected, thereby realizing accurate measurement and control of the surface temperature of carbon fiber bundles. This improves the control accuracy of the carbon fiber drying process, and can control the surface temperature of carbon fiber bundles within ±1℃, reduce the CV value of carbon fiber bundles, and achieve a moisture content of less than 2.5% and a CV value of less than 5% after drying.

[0024] 2) Compared with the existing technology, the thermal efficiency of traditional hot air drying equipment is only 30-40%. This utility model uses an infrared radiation source to heat the carbon fiber bundle, and the infrared drying thermal efficiency can reach more than 90%, which improves the thermal efficiency, significantly reduces energy consumption, and the infrared radiation energy heats the inside and surface of the carbon fiber bundle at the same time, improving temperature uniformity and helping to improve the quality of carbon fiber products.

[0025] 3) This utility model adopts a combined radiation source including a short-wave infrared radiation source and a medium-wave infrared radiation source. The short-wave infrared has strong penetrating power and can heat the inside of the fiber, while the medium-wave infrared can heat the surface of the fiber, so that the surface and inside of the carbon fiber bundle can reach a high temperature at the same time. According to the characteristics of the carbon fiber bundle to be dried and the temperature data fed back by the temperature measuring module during the drying process, the ratio of short-wave infrared and medium-wave infrared is adjusted to further improve temperature uniformity and thermal efficiency, improve energy utilization efficiency, and reduce energy consumption. It can be applied to the drying of carbon fiber bundles with different K numbers.

[0026] 4) Under the same carbon fiber processing requirements, the infrared drying equipment of this utility model is much smaller in size than the traditional hot air circulation drying equipment, and can be arranged vertically or horizontally according to the actual site conditions, saving floor space and optimizing the equipment layout of the production line.

[0027] 5) The infrared drying equipment of this utility model can be remotely controlled, has a high degree of automation, is easy to control and maintain, and can reduce the workload of on-site operation. Attached Figure Description

[0028] Figure 1 The present invention provides a schematic diagram (A) of the horizontal installation of the infrared drying equipment and a schematic diagram (B) of the arrangement of the temperature measuring module and the infrared radiation source.

[0029] Figure 2 The present invention provides a schematic diagram (A) of the vertical installation of the infrared drying equipment and a schematic diagram (B) of the arrangement of the temperature measuring module and the infrared radiation source.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1-Carbon fiber bundle; 2-Guide roller; 3-Infrared radiation source; 4-Exhaust hood; 5-Fan; 6-Exhaust branch pipe; 7-Exhaust main pipe; 8-Insulation module; 9-Reflection module; 10-Temperature measuring module; 31-Short-wave infrared radiation source; 32-Medium-wave infrared radiation source. Detailed Implementation

[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0033] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0035] According to one embodiment of the present invention, an infrared drying device for carbon fiber production is disclosed, comprising a cavity, a carbon fiber bundle channel, a heating module, a temperature measuring module, a reflection module and an exhaust module disposed within the cavity, and a control module connected to the heating module and the temperature measuring module.

[0036] According to one embodiment of this utility model, a heating module is disposed on a first side of the inner wall of the cavity. The heating module includes an infrared radiation source for emitting infrared radiation into the carbon fiber bundle channel to heat and dry the carbon fiber bundle in the channel. Compared with traditional hot air drying, the infrared radiation source has a faster heating rate and can simultaneously heat the interior and surface of the carbon fiber bundle, resulting in higher heat utilization.

[0037] According to one embodiment of this utility model, a reflective module is disposed on the second side of the inner wall of the cavity, with the first side opposite to the second side. The reflective module is a mirror-finished stainless steel reflector. A carbon fiber bundle channel is disposed between the heating module and the reflective module. Under the action of a drive, the carbon fiber bundle enters the cavity through a guide roller. An infrared radiation source emits infrared radiation, part of which reaches the carbon fiber bundle, and the other part passes through the gaps in the carbon fiber bundle to reach the mirror-finished stainless steel reflector. The mirror-finished stainless steel reflector reflects this part of the infrared radiation back to the carbon fiber bundle, thereby improving the utilization rate of infrared radiation.

[0038] During the drying process of carbon fiber bundles, the sensitivity of temperature control has a direct impact on the final quality of the carbon fiber. Temperature measurement deviation can lead to over-drying of the surface of the carbon fiber bundle or insufficient drying of the interior. Over-drying of the surface of the carbon fiber bundle will affect the wettability and bonding force between the carbon fiber bundle and the resin, resulting in unstable performance. Insufficient drying of the interior of the carbon fiber bundle will result in residual moisture affecting the bonding force between the carbon fiber and the resin, leading to an increase in the CV value.

[0039] According to one embodiment of this utility model, a temperature measuring module is disposed on the first side of the inner wall of the cavity and is used to detect the surface temperature of the carbon fiber bundle. The input end of the control module is connected to the temperature measuring module, and the output end of the control module is connected to the heating module. The control module controls the operation of the heating module according to the input of the temperature measuring module. The temperature measuring module includes an infrared temperature measuring unit and an imaging unit. The non-contact infrared temperature measuring unit can utilize the infrared radiation energy emitted by the object, convert it into an electrical signal through a sensor, and further calculate the surface temperature of the object. During the continuous transmission of the carbon fiber bundle, the non-contact infrared temperature measuring unit monitors the surface temperature of the carbon fiber bundle in real time, avoiding the temperature deviation caused by traditional contact temperature measuring elements. However, due to the gaps between the carbon fiber bundles, part of the infrared radiation reflected by the reflection module is applied to the carbon fiber bundle, and the other part passes through the gaps between the carbon fiber bundles and is applied to the infrared temperature measuring unit, affecting the accuracy of the measured temperature data. Furthermore, during the operation of the infrared drying equipment, the carbon fiber bundles are transported from the inlet to the outlet of the carbon fiber bundle channel under the drive of the guide rollers. This process is in a state of continuous dynamic transmission, and the position of the bundle gaps is constantly changing. It is impossible to avoid interference caused by infrared radiation reflected by the reflective module by adjusting the position of the infrared temperature measurement unit.

[0040] According to one embodiment of this utility model, the control module includes a correction unit, which is used to correct the interference of infrared radiation reflected by the reflection module on the infrared temperature measurement unit. The user sets the process drying temperature and the infrared radiation source power based on the characteristics of the carbon fiber bundle to be dried and the target moisture content. During the drying process, the infrared temperature sensor receives the infrared radiation emitted by the carbon fiber and the infrared radiation reflected by the reflection module and outputs temperature data to the correction unit of the control module. Simultaneously, a camera images the carbon fiber bundle channel and outputs the obtained image to the correction unit of the control module. Thus, the control module adjusts the power of the infrared radiation source based on the actual surface temperature of the obtained carbon fiber bundle.

[0041] As an optional implementation, the correction unit includes an identification element for receiving an image fed back by the imaging unit and identifying the carbon fiber bundles and the positions of the bundle gaps on the image;

[0042] The merging element is used to combine the temperature data fed back by the infrared temperature measurement unit and the image fed back by the imaging unit into a temperature distribution map;

[0043] The first outlier acquisition element is used to identify temperature data located in the gaps between carbon fiber bundles in the temperature distribution map as outlier data.

[0044] The second outlier acquisition element allows the user to set a threshold based on the characteristics of the carbon fiber tow and the set process drying temperature. The second outlier acquisition element receives the threshold set by the user and judges temperature data exceeding the set threshold as outlier data.

[0045] The actual surface temperature acquisition element is used to receive temperature data fed back by the infrared temperature measurement unit, abnormal data fed back by the first abnormal value acquisition element and / or the second abnormal value acquisition element, and delete the abnormal data from the temperature data to obtain the actual surface temperature data of the carbon fiber bundle.

[0046] More specifically, the identification elements may include edge detection elements for extracting the edge lines of the carbon fiber bundles; contour extraction elements for marking the boundaries of the carbon fiber bundles; and positioning elements for determining the gaps between the bundle contours.

[0047] In addition, the recognition element may include a grayscale segmentation element, which divides the image into bright areas (carbon fiber bundles) and dark areas (carbon fiber bundle gaps) based on the grayscale difference between the carbon fiber bundles and the gaps between them.

[0048] The control module may include an adjustment unit for receiving actual surface temperature data of the carbon fiber bundle from the temperature acquisition element and dynamically adjusting the heating power of the infrared radiation source. The adjustment unit is controlled by a PLC or DCS. When the actual surface temperature of the carbon fiber bundle deviates from the set process operating temperature by more than ±5℃, the control module responds promptly and outputs a signal to the infrared radiation source to adjust its power, precisely controlling the surface temperature of the carbon fiber bundle and improving the drying quality of the carbon fiber. Preferably, the power of the infrared radiation source can be steplessly adjusted, achieving high control precision.

[0049] According to one embodiment of the present invention, the infrared temperature measurement unit includes an infrared temperature sensor, and the imaging unit includes a camera.

[0050] According to one embodiment of this utility model, the temperature measuring module includes at least one set of infrared temperature measuring units, which are evenly distributed along the length of the cavity; each set of infrared temperature measuring units includes at least one temperature measuring point, which is evenly distributed along the width of the cavity. The number of infrared temperature measuring units and the number of imaging units can be adjusted according to the temperature control accuracy requirements of each heating area.

[0051] According to one embodiment of this utility model, the distance (i.e., the shortest distance) between the infrared temperature measuring unit and the carbon fiber bundle is 200~400mm, preferably 250~350mm. The temperature measurement accuracy of the non-contact infrared temperature measuring unit is affected by the temperature measuring distance. If the temperature measuring distance is too large, the infrared radiation energy emitted by the measured object will attenuate after being transmitted through the atmosphere, reducing the temperature measurement accuracy; if the temperature measuring distance is too small, the infrared radiation energy received by the infrared temperature measuring unit will be too strong, resulting in an excessively high temperature and affecting the service life of the infrared temperature measuring unit.

[0052] According to one embodiment of the present invention, the temperature measuring module includes at least one imaging unit, which is disposed at the outlet of the carbon fiber bundle and is evenly distributed in the cavity direction.

[0053] According to one embodiment of the present invention, the distance between the imaging unit and the carbon fiber bundle is 150~200cm, preferably 150~175cm. If the distance is too large, it will increase the volume of the infrared drying equipment; if the distance is too small, the imaging range will be limited, and the infrared radiation energy applied to the imaging unit will be too strong, resulting in excessively high temperature and affecting the service life of the imaging unit.

[0054] According to one embodiment of the present invention, the temperature measurement module is an infrared thermal imager, which includes an infrared temperature measurement unit and an imaging unit.

[0055] According to one embodiment of this utility model, the temperature measuring module includes at least one infrared thermal imager, which is disposed at the carbon fiber bundle outlet and is evenly distributed along the width direction of the cavity. The number of infrared thermal imagers can be adjusted according to the temperature control accuracy requirements of the infrared drying equipment.

[0056] According to one embodiment of this utility model, the distance between the infrared thermal imager and the carbon fiber bundle is 150~200cm, preferably 150~175cm. The temperature measurement accuracy of the non-contact infrared temperature measurement device is affected by the measurement distance. If the measurement distance is too large, the infrared radiation energy emitted by the object being measured will attenuate after being transmitted through the atmosphere, reducing the temperature measurement accuracy; if the distance is too small, the imaging range of the infrared thermal imager is limited, and the received infrared radiation energy is too strong, resulting in excessively high temperatures, which affects the service life of the infrared thermal imager.

[0057] According to one embodiment of this utility model, the reflective module is a mirror-finished stainless steel reflector. The area of ​​the reflective module is greater than or equal to the area of ​​the infrared radiation source's radiation region. The distance between the reflective module and the carbon fiber bundle is 100-200mm, preferably 125-175mm. During equipment operation, the carbon fiber bundle vibrates due to the influence of the exhaust module's fan. If the distance between the reflective module and the carbon fiber is too small, the bundle is prone to colliding with equipment components, affecting the normal passage of the bundle; if the distance is too large, some energy will diffuse outward, resulting in energy loss and reduced thermal efficiency. The reflective module is fixed to the opposite side of the heating module through elongated holes to prevent excessive deformation of the reflective module's surface due to temperature rise during operation, which would affect the passage of the carbon fiber bundle and the thermal efficiency of the infrared drying equipment.

[0058] According to one embodiment of the present invention, the heating module includes multiple sets of infrared radiation sources, which are evenly distributed along the length of the cavity; the infrared radiation sources are a combination of short-wave infrared radiation sources and medium-wave infrared radiation sources, which are alternately arranged along the width of the cavity.

[0059] Infrared radiation of different wavelengths possesses different properties. Short-wave infrared radiation has high energy density and strong penetrability, capable of heating the interior of carbon fiber bundles, while mid-wave infrared radiation can heat the surface of the carbon fiber bundles. This invention employs a combined radiation source comprising both short-wave and mid-wave infrared sources. This allows both the surface and interior of the carbon fiber bundles to reach high temperatures simultaneously, facilitating the evaporation of moisture within the bundles and effectively improving the thermal efficiency of the infrared drying equipment. It also avoids the problem of uneven drying between the surface and interior in traditional hot air circulating drying equipment. Preferably, multiple sets of infrared radiation sources are arranged along the length of the infrared drying equipment. For the first set of infrared radiation sources near the carbon fiber bundle inlet, the carbon fibers in its radiation area are in the early stage of drying. The power of the short-wave infrared radiation source accounts for 60-80% of the total power, preferably 60-70%, and the power of the medium-wave infrared radiation source accounts for 20-40% of the total power, preferably 30-40%, simultaneously drying the moisture on the surface and inside of the carbon fiber bundle. For the last set of infrared radiation sources near the carbon fiber bundle outlet, the carbon fibers in its radiation area are in the later stage of drying, and the moisture in the carbon fiber bundle is mainly concentrated on the surface. Based on the temperature data fed back by the temperature measurement module, the proportion of infrared radiation source power is appropriately reduced to 20-40%, preferably 30-40%, to prevent the high-energy-density short-wave infrared radiation from causing excessive drying inside the carbon fiber bundle. The proportion of medium-wave infrared radiation source power is increased to more than 60%, preferably 60-70%, which can effectively heat the surface of the carbon fiber bundle, achieve uniform drying, and improve energy utilization. On the other hand, the combined radiation source is suitable for drying large-tow carbon fibers. Compared to small-tow carbon fibers, the moisture inside large-tow carbon fibers is less likely to evaporate. Increasing the power of the short-wave infrared radiation source helps infrared radiation penetrate into the interior of the carbon fiber tow, thus improving drying efficiency. Preferably, in the early stage of drying, the proportion of short-wave infrared in the total power of the infrared radiation source is more than 60%, preferably 60-70%. In the later stage of drying, based on the temperature data fed back by the temperature measurement module, the proportion of short-wave infrared in the total power of the infrared radiation source is appropriately reduced to 20-40%, preferably 30-40%.

[0060] According to one embodiment of this utility model, the heating module includes multiple heating zones, each with independently controlled temperature. Preferably, based on production requirements, the process operating temperature of each heating zone is set in a gradient along the carbon fiber tow transport direction to ensure drying effect while minimizing energy consumption. Preferably, the process operating temperature for drying the carbon fiber tow is 150~200℃, the temperature gradient between any two adjacent heating zones is 10~20℃, and the temperature gradient between any two adjacent heating zones may be the same or different.

[0061] According to one embodiment of this utility model, the exhaust module is installed on the first side of the inner wall of the cavity. The ratio of the number of exhaust modules to the number of heating areas is 0.5 to 2. Preferably, each heating area corresponds to one exhaust module. The exhaust module includes an exhaust hood, a fan, and exhaust branch pipes. The number of exhaust hoods and exhaust branch pipes corresponds to the number of heating areas. The steam generated on the surface and inside of the carbon fiber bundle is extracted by the fan through the exhaust hood, and then flows into the exhaust main pipe through the exhaust branch pipes, and is discharged from the infrared drying equipment to prevent steam condensation and backflow, ensuring the heating effect, and at the same time preventing steam from overflowing into the factory.

[0062] According to one embodiment of the present invention, a heat preservation module is also provided inside the cavity of the infrared drying equipment. The heat preservation module is located on the second side of the inner wall, which can reduce energy loss and reduce energy consumption.

[0063] According to one embodiment of this utility model, the infrared drying equipment can be installed horizontally (e.g., depending on the layout requirements of the factory building). Figure 1 (as shown) or vertical (such as) Figure 2 As shown in the figure, the installation is highly flexible and conducive to the optimized layout of the factory.

[0064] The following detailed description of a specific embodiment of the present invention, with reference to the accompanying drawings, is provided by way of example.

[0065] Example 1

[0066] like Figure 1 As shown, this utility model provides a technical solution: an infrared drying device includes a cavity, a carbon fiber bundle channel disposed within the cavity, a heating module, a reflection module 9, a temperature measuring module 10, an exhaust module, a control module, and a heat preservation module 8. The infrared drying device is installed horizontally.

[0067] The carbon fiber tow channel has a carbon fiber tow inlet and a carbon fiber tow outlet. Driven by the guide roller 2, the carbon fiber tow 1 is fed into the cavity from the carbon fiber tow inlet and discharged from the cavity from the carbon fiber tow outlet. The carbon fiber tow 1 channel is located between the reflection module 9 and the heating module.

[0068] The heating module is an infrared radiation source 3, which is used to emit infrared radiation to heat and dry the carbon fiber bundles. The infrared radiation source 3 is installed on the top of the infrared drying equipment cavity. The total length of the infrared radiation source installation area is 4m and the width is 3m. There are 4 sets of infrared radiation sources, which are evenly distributed along the length of the cavity. The 4 sets of infrared radiation sources correspond to 4 heating areas. The infrared radiation sources are a combination of short-wave infrared radiation sources and medium-wave infrared radiation sources. The short-wave infrared radiation source 31 and the medium-wave infrared radiation source 32 are arranged alternately along the width of the cavity.

[0069] The reflective module 9 is a mirror stainless steel reflector used to reflect infrared radiation passing through the gaps in the carbon fiber bundles. The mirror stainless steel reflector is installed at the bottom of the cavity, and its perimeter is fixed to the bottom of the cavity through elongated holes. The distance between the mirror stainless steel reflector and the carbon fiber bundles is approximately 150mm.

[0070] The temperature measurement module 10 includes 5 sets of infrared temperature sensors and 3 cameras. The infrared temperature sensors are mounted on the top of the cavity and connected to the control module to detect the surface temperature of the carbon fiber bundle. A set of infrared temperature sensors is positioned at both ends of the infrared radiation source mounting area and between every two heating areas. Each set of infrared temperature sensors includes 3 temperature measurement points, evenly distributed along the width of the cavity. The distance between the infrared temperature sensors and the carbon fiber bundle is approximately 300mm. The cameras are connected to the control module and are used to capture images of the carbon fiber bundle channel plane. Cameras are positioned at the carbon fiber bundle outlet, evenly distributed along the width of the cavity, and approximately 150cm away from the carbon fiber bundle.

[0071] The input of the control module is connected to the infrared temperature measurement unit and the imaging unit, and the output of the control module is connected to the heating module. The control module includes a correction unit for correcting the interference of infrared radiation reflected by the reflection module on the infrared temperature measurement unit; and an adjustment unit for receiving the actual surface temperature data of the carbon fiber bundle from the temperature acquisition element and dynamically adjusting the heating power of the infrared radiation source. The correction unit includes an identification element for receiving the image from the imaging unit and identifying the carbon fiber bundle and the position of the bundle gaps on the image; a merging element for merging the temperature data from the infrared temperature measurement unit and the image from the imaging unit into a temperature distribution map; a first outlier acquisition element for identifying temperature data located in the gaps of the carbon fiber bundle in the temperature distribution map as outlier data; a second outlier acquisition element, which receives the user-set threshold based on the characteristics of the carbon fiber bundle and the set process drying temperature, and identifies temperature data exceeding the set threshold as outlier data; and an actual surface temperature acquisition element for receiving the temperature data from the infrared temperature measurement unit, the outlier data from the first outlier acquisition element and / or the second outlier acquisition element, and deleting the outlier data from the temperature data to obtain the actual surface temperature data of the carbon fiber bundle.

[0072] The exhaust module includes an exhaust hood 4, a fan 5, and an exhaust branch pipe 6. The exhaust hood 4, fan 5, and exhaust branch pipe 6 are installed on the same side of the infrared radiation source. Each heating zone corresponds to a set of exhaust hood 4, fan 5, and exhaust branch pipe 6. The steam generated on the surface and inside of the carbon fiber bundle 1 is extracted by the fan 5 through the exhaust hood 4, and then flows into the exhaust main pipe 7 through the exhaust branch pipe 6 and is discharged from the infrared drying equipment.

[0073] The bottom of the infrared drying equipment cavity is equipped with a heat preservation module 8.

[0074] The carbon fiber bundle 1 to be dried is a 50K large bundle of carbon fiber with a moisture content of about 50%. The carbon fiber bundle is dried using an infrared drying device. The carbon fiber bundle enters the infrared drying device through the guide roller 2 under the action of the drive, and the transmission speed is 10m / min.

[0075] Specifically, along the carbon fiber bundle transport direction, the process drying temperatures set for each heating zone are 180℃, 170℃, 150℃, and 140℃, respectively, and the total power of the infrared radiation source is 80kW, 75kW, 65kW, and 60kW, with short-wave infrared accounting for 70%, 60%, 45%, and 35%, and mid-wave infrared accounting for 30%, 40%, 55%, and 65%.

[0076] During the drying process, an infrared temperature sensor receives infrared radiation emitted by the carbon fibers and reflected by the reflection module, and outputs temperature data to the calibration unit of the control module. Simultaneously, a camera images the carbon fiber bundle channel, and the acquired image is output to the calibration unit of the control module. The control module then adjusts the power of the infrared radiation source based on the actual surface temperature of the carbon fiber bundle. When the actual surface temperature of the carbon fiber bundle deviates from the set process operating temperature by more than ±5℃, the control module responds promptly and outputs a signal to the infrared radiation source to adjust its power.

[0077] The dried carbon fiber bundles have a relatively uniform moisture content inside and on the surface, with a moisture content of 2.5% and a CV value of 4%.

[0078] Example 2

[0079] like Figure 2 As shown, this utility model provides a technical solution: an infrared drying device includes a cavity, a carbon fiber bundle channel disposed within the cavity, a heating module, a reflection module 9, a temperature measuring module 10, an exhaust module, a control module, and a heat preservation module 8. The infrared drying device is installed vertically.

[0080] The carbon fiber tow channel has a carbon fiber tow inlet and a carbon fiber tow outlet. Driven by the guide roller 2, the carbon fiber tow 1 is fed into the cavity from the carbon fiber tow inlet and discharged from the cavity from the carbon fiber tow outlet. The carbon fiber tow 1 channel is located between the reflection module 9 and the heating module.

[0081] The heating module is an infrared radiation source 3, which is used to emit infrared radiation to heat and dry the carbon fiber bundle. The infrared radiation source 3 is installed on the first side of the inner wall of the infrared drying equipment cavity. There are 4 sets of infrared radiation sources, which are evenly distributed along the length of the cavity. The 4 sets of infrared radiation sources correspond to 4 heating areas. The infrared radiation sources are a combination of short-wave infrared radiation sources and medium-wave infrared radiation sources. The short-wave infrared radiation source 31 and the medium-wave infrared radiation source 32 are arranged alternately along the width of the cavity.

[0082] The reflective module 9 is a mirror stainless steel reflector used to reflect infrared radiation passing through the gaps in the carbon fiber bundles. The mirror stainless steel reflector is installed on the second side of the inner wall of the cavity through elongated holes around its perimeter. The second side is opposite to the first side.

[0083] The temperature measurement module 10 includes three infrared thermal imagers, which are installed on the first side of the inner wall of the cavity. The infrared thermal imagers are connected to the control module. They receive infrared radiation emitted by the carbon fibers and reflected by the reflection module to form an infrared thermal image, used to capture an image of the carbon fiber bundle channel plane. The infrared thermal imagers are located at the carbon fiber bundle outlet and are evenly distributed along the width of the cavity.

[0084] The input end of the control module is connected to the infrared temperature measurement unit and the imaging unit, and the output end of the control module is connected to the heating module. The control module includes a correction unit, which is used to correct the interference of infrared radiation reflected by the reflection module on the infrared temperature measurement unit; and an adjustment unit, which is used to receive the actual surface temperature data of the carbon fiber bundle fed back by the temperature acquisition element and dynamically adjust the heating power of the infrared radiation source. The correction unit includes an identification element for receiving images fed back by the imaging unit and identifying the carbon fiber bundles and the locations of the bundle gaps on the images; a merging element for merging the temperature data fed back by the infrared thermometer and the images fed back by the imaging unit into a temperature distribution map; a first outlier acquisition element for identifying temperature data located in the gaps of the carbon fiber bundles in the temperature distribution map as outlier data; a second outlier acquisition element, which receives a threshold set by the user based on the characteristics of the carbon fiber bundles and the set process drying temperature, and identifies temperature data exceeding the set threshold as outlier data; and an actual surface temperature acquisition element for receiving temperature data fed back by the infrared thermometer, outlier data fed back by the first outlier acquisition element and / or the second outlier acquisition element, deleting the outlier data from the temperature data, and obtaining the actual surface temperature data of the carbon fiber bundles.

[0085] The exhaust module includes an exhaust hood 4, a fan 5, and an exhaust branch pipe 6. The exhaust hood 4, fan 5, and exhaust branch pipe 6 are installed on the same side of the infrared radiation source. Each heating zone corresponds to a set of exhaust hood 4, fan 5, and exhaust branch pipe 6. The steam generated on the surface and inside of the carbon fiber bundle 1 is extracted by the fan 5 through the exhaust hood 4, and then flows into the exhaust main pipe 7 through the exhaust branch pipe 6 and is discharged from the infrared drying equipment.

[0086] A heat preservation module 8 is installed on the second side of the inner wall of the infrared drying equipment cavity.

[0087] The carbon fiber bundle 1 to be dried is a 50K large bundle of carbon fiber with a moisture content of about 50%. The carbon fiber bundle is dried using an infrared drying device. The carbon fiber bundle enters the infrared drying device through the guide roller 2 under the action of the drive, and the transmission speed is 10m / min.

[0088] Specifically, along the carbon fiber bundle transport direction, the process drying temperatures set for each heating zone are 180℃, 170℃, 150℃, and 140℃, respectively, and the total power of the infrared radiation source is 80kW, 75kW, 65kW, and 60kW, with short-wave infrared accounting for 70%, 60%, 45%, and 35%, and mid-wave infrared accounting for 30%, 40%, 55%, and 65%.

[0089] During the drying process, an infrared thermal imager receives infrared radiation emitted by the carbon fibers and infrared radiation reflected by the reflection module, forming an infrared thermal image. This image is then output to the correction unit of the control module. The control module adjusts the power of the infrared radiation source based on the actual surface temperature of the carbon fiber bundle. When the actual surface temperature of the carbon fiber bundle deviates from the set process operating temperature by more than ±5℃, the control module responds promptly and outputs a signal to the infrared radiation source to adjust its power.

[0090] Comparative Example 1

[0091] The infrared drying equipment of Comparative Example 1 is the same as that of Example 1, except that the temperature measurement module is an infrared temperature sensor and does not include an imaging unit. The control module adjusts the heating power of the infrared radiation source according to the temperature measurement data output by the infrared temperature sensor.

[0092] The carbon fiber tow 1 to be dried is a 50K large-tow carbon fiber with a moisture content of approximately 50%. Driven by a guide roller 2, the carbon fiber tow enters the infrared drying equipment at a speed of 10 m / min. After drying, the moisture content of the carbon fiber tow is 3-4%, and the CV value is 8%.

[0093] The infrared drying equipment temperature measurement module in Comparative Example 1 only includes an infrared temperature sensor and does not include an imaging unit. The control module directly compares the carbon fiber surface temperature measured by the infrared temperature sensor with the set process operating temperature to further adjust the relevant process parameters. Because the interference from infrared radiation reflected by the mirrored stainless steel reflector is not corrected, the carbon fiber surface temperature measured by the infrared temperature sensor deviates from the actual surface temperature of the carbon fiber bundle. Compared to Example 1, the temperature detection and control accuracy of Comparative Example 1 is reduced, resulting in a larger CV value for the dried carbon fiber and a lower drying quality.

[0094] Comparative Example 2

[0095] The infrared drying equipment of Comparative Example 2 is the same as that of Example 1, except that the process drying temperature set in each heating zone is 180°C, the total power of the infrared radiation source is 80kW, the proportion of short-wave infrared is 70%, and the proportion of mid-wave infrared is 30%.

[0096] The carbon fiber tow 1 to be dried is a 50K large-tow carbon fiber with a moisture content of approximately 50%. Driven by a guide roller 2, the carbon fiber tow enters the infrared drying equipment at a speed of 10 m / min. After drying, the moisture content of the carbon fiber tow is 2.5%, and the CV value is 6.5%.

[0097] In Comparative Example 2, the process operating temperature, total power of the infrared radiation source, and ratio of short-wave infrared to mid-wave infrared were set for each heating zone. Compared with Example 1, the carbon fiber drying quality of Comparative Example 2 was reduced and the production energy consumption was increased.

Claims

1. An infrared drying device for carbon fiber production, characterized in that, The system includes a cavity, a carbon fiber bundle channel, a heating module, a temperature measuring module, a reflection module, and an exhaust module disposed within the cavity, as well as a control module connected to the heating module and the temperature measuring module. The carbon fiber bundle channel has a carbon fiber bundle inlet and a carbon fiber bundle outlet. The carbon fiber bundle is fed into the cavity from the carbon fiber bundle inlet and discharged from the cavity from the carbon fiber bundle outlet. The heating module is disposed on the first side of the inner wall of the cavity, and the heating module includes an infrared radiation source for emitting infrared radiation toward the carbon fiber bundle channel to heat and dry the carbon fiber bundle in the carbon fiber bundle channel. The reflective module is disposed on the second side of the inner wall of the cavity, with the first side opposite to the second side. The carbon fiber bundle channel is disposed between the heating module and the reflective module. The reflective module includes a reflective plate for reflecting infrared radiation emitted by the infrared radiation source. The temperature measuring module is disposed on the first side of the inner wall of the cavity and is used to detect the temperature of the surface of the carbon fiber bundle. The input terminal of the control module is connected to the temperature measuring module, and the output terminal of the control module is connected to the heating module. The control module controls the operation of the heating module according to the input of the temperature measuring module. The exhaust module is disposed on the first side of the inner wall of the cavity and is used to exhaust the steam generated on the surface and inside of the carbon fiber bundle from the cavity.

2. The infrared drying equipment according to claim 1, characterized in that, The temperature measurement module includes an infrared temperature measurement unit and an imaging unit. The infrared temperature measurement unit is connected to the control module and is used to detect the temperature of the surface of the carbon fiber bundle. The imaging unit is connected to the control module and is used to capture an image of the plane of the carbon fiber bundle channel. The control module includes a correction unit, which is used to correct the interference of infrared radiation reflected by the reflection module on the infrared temperature measurement unit in order to obtain the actual surface temperature of the carbon fiber bundle.

3. The infrared drying equipment according to claim 2, characterized in that, The infrared temperature measurement unit includes an infrared temperature sensor, and the imaging unit includes a camera. The infrared temperature sensor receives infrared radiation emitted by the carbon fiber bundle and infrared radiation reflected by the reflection module, and outputs temperature data to the correction unit of the control module. At the same time, the camera images the carbon fiber bundle channel and outputs the obtained image to the correction unit of the control module. Thus, the control module adjusts the power of the infrared radiation source according to the actual surface temperature of the carbon fiber bundle.

4. The infrared drying equipment according to claim 2, characterized in that, The temperature measurement module includes at least one set of infrared temperature measurement units, which are evenly distributed along the length of the cavity and the carbon fiber bundle channel; each set of infrared temperature measurement units includes at least one temperature measurement point, which is evenly distributed along the width of the cavity; the distance between the infrared temperature measurement unit and the carbon fiber bundle is 200~400mm.

5. The infrared drying equipment according to claim 2, characterized in that, The temperature measurement module includes at least one imaging unit, which is disposed at the outlet of the carbon fiber bundle and is evenly distributed along the width direction of the cavity and the carbon fiber bundle channel; the distance between the imaging unit and the carbon fiber bundle is 150~200cm.

6. The infrared drying equipment according to claim 2, characterized in that, The temperature measurement module is an infrared thermal imager.

7. The infrared drying equipment according to claim 1, characterized in that, The reflector is a mirror-finished stainless steel reflector, and the distance between the reflector and the carbon fiber bundle is 100~200mm; the area of ​​the reflector is greater than or equal to the area of ​​the radiation region of the infrared radiation source.

8. The infrared drying equipment according to claim 1, characterized in that, The heating module includes multiple sets of infrared radiation sources, which are evenly distributed along the length of the cavity and the carbon fiber bundle channel.

9. The infrared drying equipment according to claim 8, characterized in that, The infrared radiation source is a combination of a short-wave infrared radiation source and a mid-wave infrared radiation source, and the short-wave infrared radiation source and the mid-wave infrared radiation source are arranged alternately along the width direction of the cavity and the carbon fiber bundle channel.

10. The infrared drying equipment according to claim 1, characterized in that, The heating module includes multiple heating zones, each heating zone includes at least one set of infrared radiation sources, and each heating zone has independent temperature control.

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