Tow band opening equipment

Abstract

The invention belongs to the technical field of cigarette making equipment, and discloses tow belt opening equipment which comprises a tow belt pre-opening assembly, a tow bag conveying and weighing device and a tow belt opening assembly, the tow pre-opening assembly is arranged at the top end of a tow bag protective cover, and a tow weighing assembly is arranged at the bottom of the tow bag protective cover; the tow band pre-opening assembly is innovatively introduced to solve the problem that the suction resistance of a filter stick fluctuates due to non-uniform opening of a tow band. The assembly firstly performs preliminary loosening on the tow band, and stores the remaining tow band in the tow storage box, so that the tension is kept constant when the tow band enters a subsequent opening section, and the tow band is ensured to be opened uniformly and stably. Meanwhile, the tow package weighing monitoring system records the weight change of the tow package in real time and quickly judges whether the opening amount meets the requirements of a filter stick forming process or not, so that the forming quality and the production speed of the filter stick are improved.

Description

Technical Field

[0001] This invention relates to the field of tobacco manufacturing equipment technology, specifically to a tow belt unwinding device. Background Technology

[0002] As a core component of cigarettes, the quality of the filter rod directly determines the filtration efficiency, smoking experience, and combustion stability of the cigarette. Tow opening is a crucial process in filter rod manufacturing, playing a vital role in transforming bundled raw material fibers into loose, uniform fiber bundles. Only by achieving sufficient, uniform, and gentle tow opening can the finished filter rod possess key indicators such as adequate hardness, suitable draw resistance, and a low coefficient of variation. These indicators are also core prerequisites for ensuring the consistency and high quality of cigarette products.

[0003] Existing fiber tow opening equipment has many shortcomings: Firstly, the lack of an effective pre-opening process means that when the filament bundle directly enters the main opening unit, the initial structure is tight and the tension fluctuates greatly, which can easily lead to local over-opening or insufficient opening, resulting in significant fluctuations in the filter rod's suction resistance and affecting product consistency. Secondly, the lack of tension buffering and dynamic adjustment mechanisms leads to unstable tension in the fiber bundle during the opening process, further exacerbating the uneven opening problem. In addition, the static electricity carried by the fiber bundle can easily cause fiber agglomeration, further worsening the opening effect. Third, there is a lack of real-time monitoring and closed-loop control of the fiber tow feed amount. The existing weighing device and conveying device are mostly set up separately, which cannot provide real-time feedback on the weight change of the fiber tow package. It is difficult to accurately match the requirements of the filter rod forming process for the opening amount, which can easily lead to waste of raw materials or unqualified products flowing into subsequent processes. Fourth, the overall adaptability of the equipment is insufficient, making it difficult to meet the requirements of continuous mass production for process stability and efficiency. The operation is complex and the adjustment flexibility is lacking.

[0004] The deficiencies of the existing technology make it difficult to effectively guarantee the quality of tow opening, and the production efficiency and raw material utilization rate are low, which cannot meet the technical requirements of tobacco companies for high-quality and high-stability production of filter rods. Therefore, developing a tow belt opening device that can solve the above problems has important practical significance and application value. Summary of the Invention

[0005] The purpose of this invention is to provide a filament tow unwinding device, which aims to solve the aforementioned technical problems existing in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a filament belt opening device, comprising a filament belt pre-opening component, a filament belt opening component, and a filament bundle conveying and weighing device, wherein the filament belt pre-opening component comprises a servo sliding module and a mast lifting device, wherein a filament storage box is fixedly installed on the slide surface of the servo sliding module, and a primary opener is fixedly installed on the lifting end of the mast lifting device; The top side of the wire storage box is provided with a drive roller and a driven roller assembly arranged side by side in the horizontal direction. The drive roller bearing is connected to the front of the wire storage box, and its end passes through the back of the wire storage box and is fixedly installed with the output shaft of the servo motor. The driven roller assembly includes a driven roller body and a cylinder. The driven roller body is bearing-connected to the front of the fixed base. The fixed base is fixedly installed on the front of the filament storage box via a linear slide rail assembly. The cylinder is fixedly installed on the front of the filament storage box in a horizontal direction. A connecting plate is fixedly installed on the telescopic end of the cylinder. An adjusting screw is bearing-connected to one end of the connecting plate. One end of the adjusting screw is threaded to one side of the fixed base. The driven roller body is driven by the cylinder to move closer to or further away from the driving roller. After the driven roller body and the driving roller clamp the filament bundle for pre-opening, it enters the filament storage box for temporary storage. The wire bundle conveying and weighing device includes a wire bundle protective cover. The servo sliding module and the mast lifting device are closely attached to each other and are fixedly installed on the frame surface of the wire bundle protective cover in the vertical direction. The filament bundle passes through the pre-loosening assembly and the first-stage loosener in sequence before entering the filament bundle loosening assembly, where it is further loosened under negative pressure.

[0007] Furthermore, the pre-opening assembly of the filament bundle also includes two sets of sensor assemblies respectively disposed on the left and right sides of the filament storage box, as well as a first guide roller and two second guide rollers disposed on the inner side and upper right side of the filament storage box. A filament bundle limiting post and a guide ring are arranged in sequence along the vertical direction on the right side of the filament storage box and below the active roller.

[0008] Furthermore, static eliminators are provided on the surface of the filament storage box and above the drive roller and the slave roller to eliminate static electricity carried by the filament bundle.

[0009] Furthermore, the mast lifting device includes a linear slide rail assembly and an electric telescopic rod. The linear slide rail assembly and the electric telescopic rod are sequentially fixedly installed on the frame surface of the yarn bundle protective cover in a vertical direction. The primary unloader is fixedly installed to the frame of the yarn bundle protective cover through the linear slide rail assembly. The telescopic end of the electric telescopic rod is fixedly installed to the primary unloader. The air inlet of the primary unloader is fixedly installed to one end of the air inlet pipe assembly. The other end of the air inlet pipe assembly is connected to an air source to provide stable positive pressure air to the primary unloader for primary unloading of the yarn bundle.

[0010] Furthermore, the tow package conveying and weighing device also includes three sets of sprocket conveyor belts arranged in a straight line. Each sprocket conveyor belt consists of a mounting base and a conveying structure fixedly installed on its upper part. The tow package weighing device is arranged between the mounting base and the conveying structure of the middle sprocket conveyor belt.

[0011] Furthermore, the tow package weighing device consists of four sets of weighing sensors, which are respectively located at the four corners of the mounting base and the conveying structure.

[0012] Furthermore, the tow package protective cover is mounted above the central sprocket conveyor belt, and the tow package protective cover is surrounded by a transparent dustproof curtain that automatically retracts or releases, with a vacuum cleaner with a filter device installed on its top.

[0013] Furthermore, the filament belt opening assembly includes a secondary opener, an opening roller, a tertiary opener, a glycerin spraying assembly, and an output guide roller mechanism; The glycerin spraying assembly evenly sprays triacetin onto the filament bundle after the three-stage opening process, and the output guide roller mechanism guides the sizing filament bundle into the forming unit.

[0014] The beneficial effects of this invention are: 1. More precise tension control and more stable operation The pre-opening assembly of the filament bundle adopts a collaborative design of master and slave roller assemblies to loosen the filament bundle structure in advance, forming a uniform pretension. Combined with the dynamic buffer storage function of the filament storage box, it provides double protection for the filament bundle to enter the next opening unit with constant tension, effectively suppressing tension fluctuations and ensuring a smooth and controllable opening process. 2. More precise weight control and more stable quality The fiber bundle weighing component integrates a high-precision weighing sensor to monitor the fiber feed rate of the fiber bundle in real time, and adjusts the fiber bundle traction speed instantaneously through a closed-loop feedback system to achieve dynamic stability of the weight of a single filter rod and significantly reduce quality fluctuations. 3. More efficient use of raw materials and lower scrap rate The opening process monitors the amount of filaments in real time, automatically identifies abnormalities and issues timely alarms, preventing unqualified filaments from entering the forming process, reducing raw material waste from the source and improving resource utilization.

[0015] 4. The system is more reliable and adaptable to continuous mass production. The mechanical pre-opening and electronic weighing systems work together to significantly improve process stability and meet the needs of high-intensity, continuous production. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall three-dimensional structure of the present invention; Figure 2 This is a schematic diagram of the installation structure of the fiber bundle pre-opening assembly and the primary opener; Figure 3 This is a three-dimensional structural diagram of the pre-opening assembly for the filament bundle; Figure 4 This is a rear view structural diagram of the filament bundle pre-opening assembly; Figure 5 This is a three-dimensional structural diagram of the driven roller assembly; Figure 6 This is a three-dimensional structural diagram of the wire bundle conveying and weighing device; Figure 7 This is a three-dimensional structural diagram of the tow package weighing device; Figure 8 This is a three-dimensional structural diagram of the filament tow unwinding assembly.

[0017] Reference numerals in the attached figures; wherein: 1. Fiber bundle pre-opening assembly; 11. Fiber storage box; 111. Sensor assembly; 12. Guide ring; 13. Fiber bundle limiting post; 14. Driving roller; 15. Driven roller assembly; 151. Driven roller body; 152. Fixed base; 153. Linear slide rail assembly; 154. Connecting plate; 155. Adjusting screw; 156. Cylinder; 16. First guide roller; 17. Second guide roller; 18. Static eliminator; 19. Servo motor; 2. Fiber bundle conveying and weighing device; 21. Sprocket conveyor belt; 211. Conveying structure; 212. Mounting base; 22. Tow bundle weighing device; 221. Weighing sensor; 23. Tow bundle protective cover; 3. Tow belt opening assembly; 31. Secondary opener; 32. Opening roller; 33. Tertiary opener; 34. Glycerin spraying assembly; 35. Output guide roller mechanism; 4. Servo sliding module; 5. Primary opener; 51. Air inlet pipe assembly; 6. Mast lifting device; 61. Linear slide rail assembly; 62. Electric telescopic mast. Detailed Implementation

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the present invention will be briefly introduced below in conjunction with the accompanying drawings and descriptions of the embodiments or the prior art. Obviously, the following description of the structure of the accompanying drawings is only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. It should be noted that the description of these embodiments is for the purpose of helping to understand the present invention, but does not constitute a limitation of the present invention.

[0019] Example: Please refer to the example below. Figure 1-8 As shown, this embodiment provides a yarn bundle opening device, including a yarn bundle pre-opening component 1, a yarn bundle opening component 3, and a yarn bundle conveying and weighing device 2. The yarn bundle pre-opening component 1 includes a servo sliding module 4 and a mast lifting device 6. A yarn storage box 11 is fixedly installed on the slide surface of the servo sliding module 4, and a primary opener 5 is fixedly installed on the lifting end of the mast lifting device 6. On one side of the top of the wire storage box 11, a drive roller 14 and a driven roller assembly 15 are arranged side by side in the horizontal direction. The drive roller 14 is bearing connected to the front of the wire storage box 11, and its end passes through the back of the wire storage box 11 and is fixedly installed with the output shaft of the servo motor 19. The driven roller assembly 15 includes a driven roller body 151 and a cylinder 156. The driven roller body 151 is bearing connected to the front of the fixed seat 152. The fixed seat 152 is fixedly installed on the front of the filament storage box 11 via a linear slide rail assembly 153. The cylinder 156 is fixedly installed on the front of the filament storage box 11 in a horizontal direction. A connecting plate 154 is fixedly installed on the telescopic end of the cylinder 156. An adjusting screw 155 is bearing connected to one end of the connecting plate 154. One end of the adjusting screw 155 is threaded to one side of the fixed seat 152. The driven roller body 151 is driven by the cylinder 156 to approach or move away from the driving roller 14. After the driven roller body 151 and the driving roller 14 clamp the filament bundle for pre-opening, it enters the filament storage box 11 for temporary storage. The wire bundle conveying and weighing device 2 includes a wire bundle protective cover 23, a servo sliding module 4 and a mast lifting device 6, which are closely attached to each other and fixedly installed on the frame surface of the wire bundle protective cover 23 in a vertical direction. The filament bundle passes through the pre-loosening assembly 1 and the first-stage loosener 5 in sequence before entering the filament bundle loosening assembly 3, where it is further loosened under negative pressure.

[0020] The pre-opening assembly 1 of the filament bundle also includes two sets of sensor assemblies 111 respectively disposed on the left and right sides of the filament storage box 11, as well as a first guide roller 16 and two second guide rollers 17 disposed on the inner side and upper right side of the filament storage box 11. A filament bundle limiting post 13 and a guide ring 12 are arranged in sequence along the vertical direction on the right side of the filament storage box 11 and below the active roller 14.

[0021] Static eliminator bars 18 are provided on the surface of the filament storage box 11, corresponding to the drive roller 14 and above the roller body 151, to eliminate static electricity carried by the filament bundle.

[0022] The mast lifting device 6 includes a linear slide rail assembly 61 and an electric telescopic rod 62. The linear slide rail assembly 61 and the electric telescopic rod 62 are fixedly installed on the frame surface of the yarn bundle protective cover 23 in a vertical direction. The primary unloader 5 is fixedly installed to the frame of the yarn bundle protective cover 23 through the linear slide rail assembly 61. The telescopic end of the electric telescopic rod 62 is fixedly installed to the primary unloader 5. The air inlet of the primary unloader 5 is fixedly installed to one end of the air inlet pipe assembly 51. The other end of the air inlet pipe assembly 51 is connected to an air source to provide stable positive pressure air to the primary unloader 5 for primary unloading of the yarn bundle.

[0023] Specifically, such as Figure 1-5 As shown, after the filament bundle is placed in the position of the filament bundle weighing device 22, the servo sliding module 4 is controlled by the human-machine interface to drive the filament belt pre-opening assembly 1 to accurately deliver it to the set height. The operator directly pulls out the filament bundle head and introduces it into the filament belt pre-opening assembly 1 to complete pre-stretching and static elimination. The filament belt entering the filament belt pre-opening assembly 1 first passes through the guide ring 12 for guidance, then winds upward around the filament belt limiting post 13 and is clamped between the drive roller 14 and the slave roller 151 to complete pre-stretching. Then it descends into the filament storage box 11, passing by the first guide roller 16 and two sets of second guide rollers 17 in sequence to achieve tension buffering and path correction. Finally, static electricity is removed by the static elimination rod 18. The yarn is fed into the first-stage opener 5 under stable low tension. The electric telescopic rod 62 of the mast lifting device 6, controlled by the human-machine interface, drives the first-stage opener 5 to move above the pre-opened yarn bundle. The yarn bundle is then passed through the second-stage opener 31 of the yarn bundle opening assembly 3 for further loosening. The upper and lower opening rollers 32 then extend laterally and stretch longitudinally simultaneously. The third-stage opener 33 precisely sets the width. Subsequently, the glycerin spraying assembly 34 evenly applies glycerin. The output guide roller structure 35 smoothly guides and conveys the yarn bundle to the forming unit. The process is smooth and the operation is efficient. The yarn bundle pre-opening assembly 1 and the first-stage opener 5 are equipped with independent lifting devices and one-button positioning, which realizes flexible positioning and adjustment of the equipment and saves time and effort in operation. At the same time, such as Figure 5 As shown, by setting the driven roller assembly, the cylinder 156 can be controlled through the human-machine interface to drive the driven roller body 151 to slide laterally closer to or away from the active roller 14, so as to realize the process action of the active roller 14 and the driven roller body 151 jointly clamping the filament belt. The active roller 14 is driven to rotate actively by the servo motor 19, and the filament belt is fed by friction through the driven roller body 151, while realizing the pre-opening clamping in the lateral and longitudinal directions. like Figure 2-4As shown, the filament bundle is guided by the filament bundle limiting post 13 and enters the filament storage box 11 under the tension of the drive roller 14 and the roller body 151, where it accumulates. The filament bundle is then pulled and guided by the first guide roller 16 and the second guide roller 17 into the first-stage opener 5. The sensor assembly 111 monitors the amount of filament bundle accumulation in the filament storage box 11 and provides a signal to the industrial control host control system. When the amount of filament bundle accumulation is lower than the set value, the control system drives the servo motor 19 of the drive roller assembly 14 to accelerate rotation, accelerating the pre-opening of the filament bundle. When the amount of filament bundle in the filament storage box 11 reaches the set value, the control system drives the servo motor 19 of the drive roller assembly 14 to decelerate or rotate at normal speed, slowing down the pre-opening speed of the filament bundle.

[0024] The tow package conveying and weighing device 2 also includes three sets of sprocket conveyor belts 21 arranged in a straight line. Each sprocket conveyor belt 21 consists of a mounting base 212 and a conveying structure 211 fixedly installed on its upper part. A tow package weighing device 22 is provided between the mounting base 212 and the conveying structure 211 of the middle sprocket conveyor belt 21.

[0025] The tow package weighing device 22 consists of four sets of weighing sensors 221, which are located at the four corners of the mounting base 212 and the conveying structure 211.

[0026] The tow package protective cover 23 is mounted above the central sprocket conveyor belt 21. The tow package protective cover 23 is surrounded by a transparent dustproof curtain that automatically retracts or releases, and a vacuum cleaner with a filter device is installed on its top.

[0027] Specifically, such as Figure 6-7 As shown, the tow bag weighing device 22 is set on the middle sprocket conveyor belt 21. The three sets form a straight conveyor chain, and each set operates independently. The tow bag is transported by the AGV to the front sprocket conveyor belt 21. The tow bag is then conveyed to the middle sprocket conveyor belt 21 and weighed by the tow bag weighing device 22. The weight of the tow bag is monitored by four sets of weighing sensors 221 and the data is fed back to the control system. When the total amount of the tow bag decreases to the set value or the preset reduction difference, it is moved forward one station into the rear conveyor belt 21. On the other hand, such as Figure 6 After the tow package is conveyed to the tow package weighing device 22 by the sprocket conveyor belt 21, the transparent roller shutters around the tow package protective cover 23 are lowered to the set height by the manual operation human-machine interface to fully wrap the tow package, and the vacuum cleaner is started at the same time to perform dust removal operation.

[0028] The filament belt opening assembly 3 includes a secondary opener 31, an opening roller 32, a tertiary opener 33, a glycerin spraying assembly 34, and an output guide roller mechanism 35; The glycerin spraying assembly 34 evenly sprays triacetin onto the filament bundle after the three-stage opening, and the output guide roller mechanism 35 guides the sizing filament bundle into the forming unit.

[0029] Working principle of this type of wire tow unwinding equipment: Press the roller shutter up button on the tow package protective cover 23, and the transparent roller shutter of the tow package protective cover 23 will rise to the set height; after the tow package is placed on the front sprocket drive assembly 21, start the tow package conveying and weighing device 2 through the human-machine interface to move the tow package to the middle set position, and then lower the transparent roller shutter of the tow package protective cover 23 to the set height to completely wrap the tow package. After the pre-opening assembly 1 of the controlled filament bundle descends to the set height, the filament bundle is manually pulled out and passes through the guide ring 12 upwards around the filament bundle limiting post 13. Under the lateral unfolding and longitudinal stretching of the drive roller 14 and the driven roller 151, the filament bundle is pre-opened and then temporarily stored in the filament storage box 11. The filament bundle head passes upwards through the first guide roller 16 and the second guide roller 17 and then enters the static elimination bar 18 to remove static electricity. After the servo sliding module drives the pre-opening assembly 1 of the controlled filament bundle to rise to the set height, the mast lifting device 6 drives the first-stage opener 5 to descend close to the set height of the filament bundle and pulls the filament bundle into the second-stage opener 31. After being stretched longitudinally and laterally by the opener roller 32, the filament bundle enters the third-stage opener 33 to loosen to the set width. Glycerin is then evenly sprayed and enters the forming machine through the guide output roller 35.

[0030] Finally, it should be noted that the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A fiber bundle opening device, comprising a fiber bundle pre-opening assembly (1), a fiber bundle opening assembly (3), and a fiber bundle conveying and weighing device (2), characterized in that, The pre-opening assembly (1) of the filament bundle includes a servo sliding module (4) and a mast lifting device (6). A filament storage box (11) is fixedly installed on the slide surface of the servo sliding module (4), and a first-stage opener (5) is fixedly installed at the lifting end of the mast lifting device (6). The top side of the wire storage box (11) is provided with a drive roller (14) and a driven roller assembly (15) arranged side by side in the horizontal direction. The drive roller (14) is connected to the front of the wire storage box (11) by a bearing, and its end passes through the back of the wire storage box (11) and is fixedly installed with the output shaft of the servo motor (19). The driven roller assembly (15) includes a driven roller body (151) and a cylinder (156). The driven roller body (151) is bearing connected to the front of the fixed seat (152). The fixed seat (152) is fixedly installed on the front of the filament storage box (11) via a linear slide rail assembly (153). The cylinder (156) is fixedly installed on the front of the filament storage box (11) in the horizontal direction. A connecting plate (154) is fixedly installed on the telescopic end of the cylinder (156). An adjusting screw (155) is bearing connected to one end of the connecting plate (154). One end of the adjusting screw (155) is threaded to one side of the fixed seat (152). The driven roller body (151) is driven to approach or move away from the driving roller (14) by the cylinder (156). After the driven roller body (151) and the driving roller (14) clamp the filament bundle for pre-opening, it enters the filament storage box (11) for temporary storage. The wire bundle conveying and weighing device (2) includes a wire bundle protective cover (23), the servo sliding module (4) and the mast lifting device (6) are closely attached and fixedly installed on the frame surface of the wire bundle protective cover (23) in the vertical direction; The filament bundle passes through the pre-loosening assembly (1) and the first-stage loosening device (5) in sequence before entering the filament bundle loosening assembly (3), and is further loosened under the action of negative pressure.

2. The fiber bundle unwinding device according to claim 1, characterized in that, The pre-opening assembly (1) of the filament bundle also includes two sets of sensor assemblies (111) respectively disposed on the left and right sides of the filament storage box (11), as well as a first guide roller (16) and two second guide rollers (17) disposed on the inner side and upper right side of the filament storage box (11). A filament bundle limiting post (13) and a guide ring (12) are arranged in sequence along the vertical direction on the right side of the filament storage box (11) and below the active roller (14).

3. The fiber bundle unwinding device according to claim 2, characterized in that, Static eliminator bars (18) are provided on the surface of the filament storage box (11) and above the drive roller (14) and the slave roller (151) to eliminate static electricity carried by the filament bundle.

4. The fiber bundle unwinding device according to claim 3, characterized in that, The mast lifting device (6) includes a linear slide rail assembly (61) and an electric telescopic rod (62). The linear slide rail assembly (61) and the electric telescopic rod (62) are fixedly installed on the frame surface of the wire bundle protective cover (23) in a vertical direction. The first-stage unloader (5) is fixedly installed on the frame of the wire bundle protective cover (23) through the linear slide rail assembly (61). The telescopic end of the electric telescopic rod (62) is fixedly installed on the first-stage unloader (5). The air inlet of the first-stage unloader (5) is fixedly installed on one end of the air inlet pipe assembly (51). The other end of the air inlet pipe assembly (51) is connected to an air source to provide stable positive pressure air to the first-stage unloader (5) for first-stage unloading of the wire bundle.

5. The tow belt unwinding device according to claim 1, characterized in that, The tow package conveying and weighing device (2) also includes three sets of sprocket conveyor belts (21) arranged in a straight line. The sprocket conveyor belt (21) consists of a mounting base (212) and a conveying structure (211) fixedly installed on its upper part. A tow package weighing device (22) is provided between the mounting base (212) and the conveying structure (211) of the middle sprocket conveyor belt (21).

6. The tow belt unwinding device according to claim 5, characterized in that, The tow package weighing device (22) consists of four sets of weighing sensors (221), which are located between the four corners of the mounting base (212) and the conveying structure (211).

7. The fiber bundle unwinding device according to claim 6, characterized in that, The tow package protective cover (23) is mounted on top of the sprocket conveyor belt (21) in the middle. The tow package protective cover (23) is surrounded by a transparent dustproof curtain that automatically retracts or releases, and a vacuum cleaner with a filter device is installed on its top.

8. The fiber bundle unwinding device according to claim 3, characterized in that, The filament belt opening assembly (3) includes a secondary opener (31), an opening roller (32), a tertiary opener (33), a glycerin spraying assembly (34), and an output guide roller mechanism (35). The glycerin spraying assembly (34) evenly sprays triacetin onto the filament bundle after the third-stage opening, and the output guide roller mechanism (35) guides the sizing filament bundle into the forming unit.

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