A draw heat box

Abstract

The utility model discloses a kind of drafting hot boxes, comprising: cabinet, cabinet includes mutually separable heat preservation upper cabinet and heat preservation lower cabinet, and the between heat preservation upper cabinet and heat preservation lower cabinet is defined into the filament duct for filament passing;Circulating air system is set in cabinet, including at least one by circulating fan and heating unit and is composed of circulating air unit, it is characterized in that, circulating air system further includes one static pressure chamber and at least two paths from static pressure chamber to filament duct, with different flow ratio of air supply channel.This utility model is by the main air path, air supplement path and the anti-backflow air path and is constituted by multiple air supply channels, and cooperate with L type static pressure orifice plate and C shape deflector plate and other structures, accurately distribute and control heating airflow, while cooperate with liftable, detachable modular cabinet structure, effectively improve the temperature uniformity in cabinet, improve product quality, and enhance the process adaptability and transportation convenience of equipment.

Description

Technical Field

[0001] This utility model relates to the field of chemical fiber production equipment technology, and in particular to a drawing heating box. Background Technology

[0002] The drawing heat box is a key piece of equipment in the production of chemical fibers for heat setting of fiber bundles. The uniformity of its temperature and air velocity directly affects the physical properties and quality of the final finished fiber.

[0003] In existing technologies, drawing ovens typically employ either direct heating with electric heating plates or unidirectional hot air circulation heating. The electric heating plate approach suffers from uneven heating of the filaments due to varying distances between the filaments and the heating plate, as well as uneven temperature distribution within the heating plate itself. This negatively impacts product quality and makes cleaning after filament breakage difficult. The unidirectional hot air circulation approach, usually with a hinged lid, limits the oven's width, making it difficult to meet the ever-increasing demands for high production capacity. Furthermore, its air duct design is often simple, with the circulating fan typically using a fixed airflow design, unable to be adjusted according to process requirements. This can easily create "cold-hot clashes" or temperature dead zones within the oven, leading to air pressure loss and temperature fluctuations, ultimately affecting the uniformity and stability of filament drawing. In addition, with the increasing width of production lines, large-scale integrated drawing ovens face challenges in road transportation due to their excessive width and height. This not only necessitates the use of specialized vehicles, leading to a sharp increase in transportation costs, but also reduces equipment precision through repeated disassembly and reassembly, further impacting heating efficiency and uniformity.

[0004] Therefore, how to provide a drawing heat box that can achieve wide-range and efficient production, ensure uniform heating, has adjustable air volume, and is easy to transport and maintain has become a technical problem that urgently needs to be solved in this field. Utility Model Content

[0005] The purpose of this utility model is to provide a drawing heating box, which aims to solve the technical problems of uneven heating, unadjustable air volume, limited width, and inconvenient transportation and installation in the existing drawing heating boxes.

[0006] This utility model provides a drawing heating box, comprising:

[0007] The box body includes a separable upper insulated box body and a lower insulated box body, and a wire bundle passage is defined between the upper insulated box body and the lower insulated box body for the wire bundle to pass through.

[0008] A circulating air system is installed inside the box to generate heated airflow that circulates within the filament tunnel. The circulating air system includes at least one circulating air unit, and each circulating air unit includes a circulating fan and a heating unit.

[0009] The circulating air system also includes a static pressure chamber and at least two air supply channels with different flow ratios that connect the static pressure chamber and the fiber bundle channel.

[0010] Optionally, the enclosure also includes a lifting assembly for driving the upper insulation enclosure to rise and fall relative to the lower insulation enclosure.

[0011] Optionally, the lifting assembly includes a geared motor and a screw drive mechanism or lead screw lifting mechanism that is connected to the geared motor.

[0012] Optionally, at least two air supply channels include:

[0013] The main airflow path leads the airflow into the fiber bundle channel.

[0014] The supplementary air path allows airflow to enter the fiber bundle channel to compensate for the air volume of the main air path.

[0015] Optionally, an air regulating vent assembly is provided on the main air duct, which is used to adjust the airflow direction and / or air volume entering the filament duct.

[0016] Optionally, it also includes a first air volume regulating device connected to the air outlet assembly, the first air volume regulating device being used to drive the air outlet assembly to operate.

[0017] Optionally, at least two air supply channels also include a backflow prevention air path, which is equipped with a first make-up air box. The airflow enters the inlet or outlet of the fiber bundle channel through the first make-up air box to form an air curtain.

[0018] Optionally, it also includes a second airflow regulating device connected to the anti-backflow air path, the second airflow regulating device being used to regulate the airflow entering the first make-up air box.

[0019] Optionally, the main air path, the make-up air path, and the anti-backflow air path are all provided with openings to send airflow out of the static pressure chamber, and the ratio of the opening areas of the three air paths is 4:1:1.

[0020] Optionally, the housing is composed of multiple housing modules connected in series along the length of the filament channel, and each housing module is equipped with a circulating air unit of the circulating air system.

[0021] Based on the technical content disclosed in this utility model, the following beneficial effects are achieved:

[0022] The technical solution provided by this utility model, by designing the box as a separable insulated upper box and insulated lower box, and setting up a circulating air system including a static pressure chamber and at least two air supply channels with different flow ratios, brings significant beneficial effects. First, the design of multiple air supply channels, such as the main air channel, the supplementary air channel, and the anti-backflow air channel, allows the airflow from the static pressure chamber to be precisely distributed and controlled. Part of it serves as the main heating airflow, part is used to supplement and stabilize the air pressure, and another part can form an air curtain at the inlet and outlet, effectively preventing the intrusion of cold air from the outside or the leakage of internal hot airflow. This greatly improves the uniformity of the temperature field and wind speed field within the fiber bundle channel, ensuring that the fiber bundle is heated uniformly across its entire width, thereby significantly improving the quality and strength uniformity of the finished fiber. Second, by designing and adjusting the flow ratio of different channels, it can flexibly adapt to the production process requirements of different fineness and speed, achieving refined control of the airflow organization within the box, avoiding air pressure loss and the generation of local "weak stretching zones," and improving heating efficiency.

[0023] Other features and advantages of the present invention will become clear from the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the present invention and, together with their description, serve to explain the principles of the present invention.

[0025] Figure 1 This is a schematic cross-sectional view of the circulating air path and internal structure of this utility model;

[0026] Figure 2 This is a top view of the second-layer air duct of this utility model;

[0027] Figure 3 This is a top view of the first layer of the air duct of this utility model;

[0028] Figure 4 This is a schematic diagram of the lifting and transmission structure of this utility model.

[0029] Explanation of reference numerals in the attached drawings: 1. Air inlet assembly; 2. Insulated upper housing; 3. Fiber bundle duct; 4. Air supply plate; 5. First static pressure chamber; 6. Baffle plate; 7. Temperature sensor; 8. Fan intake; 9. Return air plate; 10. Return air filter; 11. First air supply box; 12. Second static pressure chamber; 13. Second air supply box; 14. Static pressure plate; 15. Insulated lower housing; 16. Equipment support leg; 17. Circulating fan; 18. Heating unit; 19. Air supply valve; 20. Lifting assembly; 21. First airflow regulating device; 22. Second airflow regulating device; 23. Inlet / outlet baffle; 24. Gear motor; 25. Air supply box channel; 26. First layer air duct guide plate. Detailed Implementation

[0030] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present invention.

[0031] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0032] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0033] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0034] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0035] Please see Figures 1 to 4 This utility model provides a drawing heating box, the overall concept of which is to solve the pain points of traditional heating boxes in terms of wide-range production, temperature uniformity, process adaptability and transportation convenience by using a modular and separable box structure combined with a refined and adjustable multi-path circulating air system.

[0036] I. Overall Structure and Modular Design

[0037] The drawing heat box of this utility model mainly includes a box body and a circulating air system installed inside the box body.

[0038] To address the transportation challenges posed by the excessive width of large integrated thermal boxes, this invention employs a modular splicing design for the box body. Specifically, a complete, long-length drawing thermal box is constructed by detachably splicing at least two independent box modules along the length of the wire bundle passageway 3.

[0039] Taking a heat box with a total length of 6 meters and a width of 4.7 meters as an example, this heat box can be composed of two box modules, each 3 meters long and 4.7 meters wide. During factory shipment, these two box modules are transported separately. During transport, the box modules can be rotated 90 degrees so that their 3-meter length corresponds to the width of the truck, and their 4.7-meter width corresponds to the length of the truck, thus ensuring that the transport width does not exceed 3 meters, meeting the requirements of conventional road transport. Upon arrival at the site, the two box modules are precisely joined and spliced ​​along their 4.7-meter width to form an integrated stretching heat box with a total length of 6 meters.

[0040] This modular splicing design along the length direction not only ensures the accuracy and performance of the equipment when it finally operates as an integrated structure, but also cleverly solves the problem of long-distance transportation of wide-width equipment, significantly reducing transportation costs and risks.

[0041] Each independent housing module includes a detachable, liftable structure. Specifically, it includes an upper insulated housing 2 and a lower insulated housing 15, both filled with insulation material. The upper insulated housing 2 can be driven by a lifting assembly 20 to achieve vertical lifting relative to the fixed lower insulated housing 15. Preferably, the lifting assembly 20 can be a screw drive mechanism or a lead screw lifting mechanism driven by a geared motor 24 (such as a worm gear reducer) to achieve smooth and precise start-stop control. When the upper insulated housing 2 and the lower insulated housing 15 are closed, they together define the core process area for the fiber bundle to pass through, namely the fiber bundle passage 3. This lifting and opening design greatly facilitates the threading of the fiber bundle, cleaning of broken fibers, and equipment maintenance, significantly improving operational efficiency and safety. The entire housing is stably supported by multiple equipment legs 16. Both the inlet and outlet of the box are equipped with adjustable gap inlet and outlet baffles 23, which are used to reduce heat loss during normal production and provide operating space during wire drawing.

[0042] II. Circulating air system and its working path

[0043] The circulating air system is the core component ensuring uniform heating of the filament bundle, and its main body consists of independent circulating air units located within each housing module. This embodiment demonstrates a structure composed of a first circulating air unit and a second circulating air unit, both of which have the same structure and working principle. The following will focus on the first circulating air unit ( Figure 1Taking the left half as an example, we will explain its structure and airflow circulation path in detail.

[0044] Phase 1: Return Air, Heating, and Pressurization

[0045] The circulating airflow first flows from the filament duct 3 to the return air area. Here, the airflow passes sequentially through the return air filter 10, which filters dust and broken filaments, and the return air perforated plate 9 with evenly distributed openings. Subsequently, the airflow is sent to the heating unit 18. The heating unit 18 can be equipped with an electric heater (such as a finned electric heating tube assembly) or a steam heater, as needed, and its function is to heat the circulating air to the temperature set by the process.

[0046] The heated high-temperature airflow is drawn into the circulating fan 17 through the fan intake 8. The circulating fan 17 is preferably a high-temperature resistant centrifugal or axial fan, providing power for the entire circulation and pressurizing the high-temperature airflow. The pressurized high-temperature airflow then enters the duct after the fan outlet and flows through the first-layer duct guide plate 26. Figure 3 As can be seen, the first-layer air duct guide plate 26 has a C-shaped or hook-shaped profile. Its function is to smoothly guide and disperse the airflow ejected at high speed from the fan outlet into a wider air duct, effectively avoiding airflow impact and eddy current generation, and achieving preliminary flow stabilization and uniform flow. This is the first step in reducing system pressure loss and improving efficiency.

[0047] Phase Two: Voltage Stabilization and Equalization

[0048] The pressurized, high-temperature airflow rises and enters a crucial pressure equalization structure, namely the static pressure orifice plate 14. For example... Figure 1 As shown, the static pressure orifice plate 14 is an L-shaped component consisting of a horizontally positioned plate and a vertically positioned plate, both of which are densely covered with small holes. The airflow must first pass through the horizontal plate, then turn 90 degrees within a confined space, and finally pass through the vertical plate. This design forces the airflow through two perforations and one turn, significantly increasing airflow resistance and eliminating directionality, thereby achieving efficient pressure equalization. This ensures that the airflow entering the first static pressure chamber 5 of the upper layer has a highly uniform pressure and velocity distribution across the entire chamber's cross-section, laying a solid foundation for subsequent precise air delivery and serving as a crucial guarantee for achieving final heating uniformity.

[0049] Phase 3: Three-way diversion and precise air supply

[0050] After the airflow enters the uniformly pressurized first static pressure chamber 5, it is cleverly divided into three air supply channels with different flow ratios, each performing a different function. In this embodiment, the flow distribution ratio is achieved by pre-setting the flow area of ​​different air channels. Specifically, the total opening area of ​​the main air channel, the makeup air channel, and the anti-backflow air channel is designed in a specific ratio (e.g., 4:1:1). Since the three air channels share the same air source in the static pressure chamber, the airflow will naturally be distributed in a ratio approximately proportional to the flow area, thereby achieving a basic flow distribution of about 2 / 3, 1 / 6, and 1 / 6.

[0051] Main airflow (red airflow, accounting for approximately 2 / 3 of the flow): This airflow serves as the primary heating source. The airflow is first guided by the baffle plate 6, and then blown towards the fiber bundle channel 3 through the air regulating assembly 1. The air regulating assembly 1 is preferably a multi-blade linkage regulating valve (i.e., a louvered air outlet), a rotary air valve, or a double-layer blade air outlet, and is connected to an external first airflow regulating device 21 (such as an electric actuator or a pneumatic actuator). The operator can precisely adjust the opening and even the angle of the blades through this device, thereby controlling the size and direction of the airflow blowing towards the fiber bundle from the main airflow, achieving "airflow following the fiber," ensuring direct and efficient heating, and avoiding burrs caused by improper airflow direction disrupting the fiber bundle.

[0052] Makeup air path (blue air path, accounting for approximately 1 / 6 of the flow): This airflow is first guided by a baffle plate 6 and then enters the second static pressure chamber 12 through the bottom inlets of two parallel second static pressure chambers 12 from the first static pressure chamber 5. It then enters the wire bundle channel 3 through the makeup air perforation plate 4 with fixed apertures at the top of the second static pressure chamber 12. Preferably, a baffle plate 6 is installed inside the second static pressure chamber 12 for guidance. It provides a constant and stable base airflow. Its beneficial effect is that when the main air path is reduced due to process requirements, this makeup airflow ensures that the total airflow and total pressure in the wire bundle channel 3 do not drop excessively, thereby maintaining the stability and temperature uniformity of the entire heating environment and avoiding the generation of local "weak stretching zones".

[0053] Backflow prevention airflow path (magenta airflow path, accounting for approximately 1 / 6 of the flow): This portion of the airflow is drawn out from the first static pressure chamber 5, and guided to the first makeup air box 11 located at the end of the box body through the makeup air box channel 25. In such a way... Figure 1 In the sectional view shown, because the first air supply box 11 and the air supply box channel 25 are located at the end of the equipment and their structure is obscured, their paths are schematically drawn with magenta dashed lines. The specific planar layout of this path is determined by... Figure 2The airflow is clearly shown, with magenta arrows indicating the direction of the airflow. After being redistributed within the first make-up air box 11, the airflow is blown out, forming a positive pressure "air curtain" at the end of the first circulating air unit (i.e., the module connection). The beneficial effect is that this air curtain, acting as an internal barrier, effectively prevents hot air about to enter the return air zone from flowing back, thus ensuring the unidirectionality and stability of the airflow organization within the module and avoiding interference with the temperature field of the next-level housing module. The airflow in this path can be adjusted via a second airflow regulating device 22 (such as a manual or electric regulating valve) connected to the make-up air box channel 25.

[0054] Phase 4: Combined Heating and Circulation

[0055] The three airflows converge within the fiber bundle channel 3, heating the fiber bundle uniformly and controllably from all directions. After heat exchange, the slightly cooled airflow returns to the return air zone, entering the next cycle.

[0056] Second circulating air unit ( Figure 1 The working principle of the right half is basically the same as that of the first circulating air unit, and it also has a corresponding structure such as the second static pressure chamber 12 inside. It is worth noting that the second makeup air box 13, located at the very end of the entire hot box, has a different function from the first makeup air box 11. The second makeup air box 13 also forms an "air curtain", but its main function is to act as an outlet barrier for the entire equipment, to prevent cold air from the outside environment from being drawn in at the fiber bundle outlet, thereby avoiding uneven temperature in the outlet area due to "cold and hot collision" and ensuring the stability of product quality.

[0057] In addition, the system is equipped with multiple temperature sensors 7 at key locations to monitor temperature distribution in real time and provide data support for closed-loop control. Specifically, such as Figure 1 As shown, at least one temperature sensor 7 has its probe inserted into the fiber bundle channel 3 to directly measure the actual temperature of the fiber bundle during the heating process, ensuring the accuracy of the process temperature. Other temperature sensors 7 can be arranged in the first static pressure chamber 5, the second static pressure chamber 12, or the return air path to monitor the supply air temperature and return air temperature, thereby evaluating the heating efficiency and temperature uniformity of the entire circulation unit. Simultaneously, the housing is also independently equipped with a makeup air valve 19. Adjustment of this valve allows for the supply of fresh air to the system when needed, maintaining a slight positive pressure inside the housing to prevent external contaminants from entering.

[0058] In summary, this utility model, through its unique split-type lifting box, modular design, and innovative three-way air circulation system, achieves precise and controllable management of the internal temperature and airflow fields of the heat box, effectively solving many technical bottlenecks of traditional drawing heat boxes and providing reliable equipment support for the production of high-quality, highly uniform chemical fiber products.

[0059] Although specific embodiments of the present invention have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A drawing heating box, characterized in that, include: The box body includes a separable upper insulated box body and a lower insulated box body, and a wire bundle passage is defined between the upper insulated box body and the lower insulated box body for the wire bundle to pass through. A circulating air system is provided inside the housing to generate heated airflow that circulates within the filament tunnel. The circulating air system includes at least one circulating air unit, and each circulating air unit includes a circulating fan and a heating unit. The circulating air system further includes a static pressure chamber and at least two air supply channels with different flow ratios connected to the static pressure chamber and the filament bundle channel.

2. The drawing heating box according to claim 1, characterized in that, The enclosure also includes a lifting assembly for driving the upper insulated enclosure to rise and fall relative to the lower insulated enclosure.

3. A drawing heating box according to claim 2, characterized in that, The lifting assembly includes a geared motor and a screw drive mechanism or lead screw lifting mechanism that is connected to the geared motor.

4. A drawing heating box according to claim 1, characterized in that, At least two of the aforementioned air supply channels include: The main airflow path leads to the entry of the fiber bundle channel. The supplementary air path allows airflow to enter the fiber bundle channel to compensate for the air volume of the main air path.

5. A drawing heating box according to claim 4, characterized in that, An air regulating vent assembly is provided on the main air path, which is used to adjust the airflow direction and / or air volume entering the filament channel.

6. A drawing heating box according to claim 5, characterized in that, It also includes a first airflow regulating device connected to the airflow regulating assembly, the first airflow regulating device being used to drive the airflow regulating assembly to operate.

7. A drawing heating box according to claim 4, characterized in that, The at least two air supply channels also include a backflow prevention air channel, which is equipped with a first make-up air box. The airflow enters the inlet or outlet of the filament channel through the first make-up air box to form an air curtain.

8. A drawing heating box according to claim 7, characterized in that, It also includes a second airflow regulating device connected to the anti-backflow air path, the second airflow regulating device being used to regulate the airflow entering the first make-up air box.

9. A drawing heating box according to claim 7, characterized in that, The main air path, the make-up air path, and the anti-backflow air path are all provided with openings to send airflow out of the static pressure chamber, and the ratio of the opening areas of the three air paths is 4:1:

1.

10. A drawing heating box according to claim 1, characterized in that, The housing is composed of multiple housing modules connected in series along the length of the filament channel, and each housing module is equipped with a circulating air unit of the circulating air system.

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