A single plate multi-orifice composite type spinneret assembly

Abstract

The present application relates to a kind of single board porous composite type spinneret assembly, and jet assembly includes cooling sleeve, outer sleeve, spinneret, heating plate, wherein spinneret and heating plate are fixed in outer sleeve, spinneret is located on the upside of heating plate, multiple adjusting chambers are arranged in diamond on spinneret, and heating plate is distributed with heater corresponding to adjusting chamber one by one in diamond, and there is a cooling sleeve corresponding below each heater, and each adjusting chamber is provided with a flow guide pipe;Cooling and shaping are carried out to filament bundle using airflow, and the injection direction of airflow is parallel with the axis of filament bundle, to ensure cooling effect;Based on the influence of temperature on melt, and the contact position of annular conductive sheet and adjusting resistance is adjusted based on the resistance generated during the flow of melt in flow guide pipe, so that the heating power of heater and the jet speed when melt passes through flow guide pipe form negative feedback mechanism to adjust jet speed, to maintain the stability of jet speed.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a single-plate multi-hole composite spinneret assembly. Background Technology

[0002] Melt spinning is generally carried out in a spinning machine. During spinning, a heat transfer medium is typically used to keep the melt at a constant temperature, ensuring that the melt temperature remains essentially the same throughout the flow as when the fibers are being spun. Since the melt needs to pass through the spinneret orifice at a low apparent viscosity during spinning, and the apparent viscosity of fiber-grade materials generally decreases with increasing temperature, the spinning temperature needs to be 20-30°C higher than the material's melting point to maintain the spinning rate. However, under normal circumstances, fiber-forming polymers have poor thermal stability above their melting point, and excessively high temperatures can damage the material structure, leading to thermal decomposition. Furthermore, excessively high temperatures can cause the filament bundle at the spinneret orifice to not fully cool and solidify immediately after being ejected. As the filament bundle length increases, its own weight can stretch and deform it, affecting the quality of the filament bundle.

[0003] In existing spinning assembly designs, spinnerets are mostly arranged in a uniform or traditional rectangular pattern, which has the following problems: conventional arrangement leads to insufficient cooling of the inner filaments, affecting the solidification and molding effect; in the current single-plate multi-hole spinning assembly, the guide holes cause flow resistance under high output, and the different spinneret rates of different guide holes affect the extrusion uniformity.

[0004] In view of the shortcomings of existing technology, technological improvements are needed based on the aforementioned deficiencies. Summary of the Invention

[0005] In view of this, the object of the present invention is to provide a single-plate multi-hole composite spinneret assembly to solve the above problems.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A multi-hole composite spinneret assembly for single-plate spinning includes a guide section, a filter section, and a distribution section sequentially arranged on the upper side of the spinneret assembly. A melt inlet is opened in the middle of the upper side of the guide section. The guide section, filter section, distribution section, and spinneret assembly are connected end to end by a sealing structure to form a complete spinneret end. The spinneret assembly specifically includes a cooling sleeve, an outer sleeve, a spinneret plate, and a heating plate coaxially assembled. The spinneret plate and the heating plate are vertically fixed to the inner wall of the outer sleeve by bolts, and an insulating heat insulation layer is provided between the spinneret plate and the heating plate. The spinneret plate is located directly above the heating plate. Multiple cylindrical adjustment chambers penetrating the plate are arranged in a diamond array on the surface of the spinneret plate. A plate-shaped heater is embedded in the surface of the heating plate corresponding to the center of each adjustment chamber. All heaters form a diamond distribution array on the surface of the heating plate that is consistent with the arrangement of the adjustment chambers.

[0007] Furthermore, a cooling sleeve is coaxially arranged directly below each of the heating elements, with the upper end face of the cooling sleeve tightly fitted to the bottom surface of the heating plate; a vertically penetrating drain tube is inserted into each of the adjustment chambers, and the heating area of ​​the heating element is directly opposite the upper end of the drain tube to achieve local radiant heating.

[0008] Furthermore, two strip-shaped regulating resistors are symmetrically embedded in the inner wall of each regulating chamber, and L-shaped conductive plates are fixed on both sides of the bottom of the regulating chamber; the upper end of the conductive plate is electrically connected to the top of the regulating resistor on the same side through a silver alloy wire, and the lower ends of the conductive plates on both sides are respectively connected to the positive and negative terminals of an external DC power supply through wires, and one of the conductive plates is also connected to the power supply terminal of the heater through a branch wire.

[0009] Furthermore, the lower end of the drainage tube is processed into an inwardly tapered structure, and an annular limiting protrusion is integrally formed on the upper outer wall of the drainage tube; a copper annular conductive sheet is tightly wrapped around the outer side of the limiting protrusion, and the outer circumferential surface of the annular conductive sheet maintains sliding electrical contact with the inner sidewalls of the two adjusting resistors.

[0010] Furthermore, a spiral positioning spring is sleeved on the outside of the drainage tube. The upper end of the positioning spring is welded and fixed to the bottom surface of the limiting protrusion, and the lower end of the positioning spring is fixedly connected to the upper surface of the heating plate through a snap-fit ​​structure. In its natural state, the positioning spring keeps the annular conductive sheet of the drainage tube and the regulating resistor at a constant contact pressure.

[0011] The beneficial effects of this invention are as follows: This invention utilizes airflow to cool and shape the filament bundle, and the direction of the airflow jet is parallel to the axis of the filament bundle, ensuring the cooling effect; simultaneously, when the airflow flows in the exhaust pipe, a negative pressure is formed at the constriction part of the exhaust pipe, making the air pressure in the area below the guide pipe lower than the ambient air pressure, creating a pressure difference that decreases as the air pressure gets closer to the guide pipe, reducing the pulling force on the filament at the lower end of the guide pipe, and preventing the filament from being stretched and deformed before it is fully cooled and shaped; based on the influence of temperature on the melt, and the resistance generated by the melt flowing in the guide pipe, the contact point between the annular conductive plate and the regulating resistor is adjusted, so that the heating power of the heater and the filament spinning rate when the melt passes through the guide pipe form a negative feedback mechanism to self-adjust the filament spinning rate and maintain the stability of the filament spinning rate; and the current of the circuit adjusted by the melt driving the guide pipe to form a feedback mechanism with the electromagnet, adjusting the cooling airflow size to ensure the cooling effect. Attached Figure Description

[0012] Figure 1 This is a structural diagram of the spinneret end; Figure 2 This is a diagram of the internal structure of the spinneret assembly; Figure 3 for Figure 2 Enlarged view of part A in the middle; Figure 4Diagram of the drainage tube structure; Figure 5 Here is a structural diagram of the cooling sleeve; Figure 6 This is a cross-sectional view of the lower end of the drainage pipe when there is only one nozzle.

[0013] The following numbers are labeled in the diagram: 1. Guide section; 2. Filter section; 3. Distribution section; 4. Spinneret assembly; 5. Cooling sleeve; 501. Negative pressure chamber; 502. Exhaust pipe; 503. Inlet; 504. Air inlet; 6. Outer sleeve; 7. Spinneret plate; 701. Adjustment chamber; 8. Heating plate; 9. Heater; 10. Drain tube; 1001. Limiting protrusion; 11. Adjusting resistor; 12. Conductive sheet; 13. Annular conductive sheet; 14. Positioning spring; 15. Plug; 16. Magnet block; 17. Electromagnet; 18. Limiting tension spring. Detailed Implementation

[0014] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: like Figure 1-6 As shown, a multi-hole composite spinneret assembly for a single-plate design is provided. The spinneret assembly 4 has a guide section 1, a filter section 2, and a distribution section 3 on its upper side. A melt inlet is provided in the middle of the upper side of the guide section 1. The guide section 1, filter section 2, distribution section 3, and spinneret assembly 4 are connected end to end to form a complete spinneret end, facilitating the melt to pass through the guide section 1, filter section 2, and distribution section 3 and finally enter the spinneret assembly 4. The spinneret assembly 4 includes a cooling sleeve 5, an outer sleeve 6, a spinneret 7, and a heating plate 8, wherein the spinneret 7 and the heating plate 8 are both fixed to the outer sleeve. Inside the spinneret 7, the spinneret 7 is located on the upper side of the heating plate 8. Multiple adjustment chambers 701 are arranged in a diamond pattern on the spinneret 7, and the heating plate 8 has heaters 9 that correspond one-to-one with the adjustment chambers 701 in a diamond pattern. Below each heater 9, there is a cooling sleeve 5. Each adjustment chamber 7 is provided with a guide tube 10. The heater 9 heats the guide tube 10, so that the melt is rapidly heated in the guide tube 10, reducing the viscosity of the melt and improving the fluidity of the melt to meet the requirements of spinnereting. The cooling sleeve 5 cools the filament bundle ejected from the guide tube 10.

[0015] In this embodiment, two regulating resistors 11 are symmetrically arranged on the side wall of the regulating chamber 701. Conductive plates 12 are symmetrically fixed at the lower end of the regulating chamber 701. The conductive plates 12 are connected to the upper end of the regulating resistor 11 on the corresponding side through wires. The two conductive plates 12 are connected to the power supply and the heater 9 through wires respectively. The drainage tube 10 contracts near the lower port, making the lower port of the drainage tube 10 smaller than the upper port. A limiting protrusion 1001 is provided near the upper end of the drainage tube 10. An annular conductive plate 13 is wrapped around the side of the limiting protrusion 1001. The annular conductive plate 13 contacts the regulating resistor 11, so that the power supply, regulating resistor 11 and heater 9 form a series closed circuit. The drainage tube 10 slides up and down to adjust the position of the annular conductive plate 13, thereby adjusting the size of the regulating resistor 11 connected to the circuit. A positioning spring 14 is sleeved on the drainage tube 10. The upper end of the positioning spring 14 is fixedly connected to the limiting protrusion 1001, and the lower end of the limiting spring 14 is fixedly connected to the heating plate 8.

[0016] In this embodiment, the cooling sleeve 5 has an annular structure, which facilitates the wire bundle to pass through the middle of the cooling sleeve 5. The upper side of the cooling sleeve 5 is provided with a threaded part to facilitate threaded connection with the heating plate 8. The cooling sleeve 5 includes two parts: an annular negative pressure cavity 501 and an exhaust pipe 502. The exhaust pipe 502 is evenly distributed around the outside of the negative pressure cavity 501. Multiple rows of suction holes 503 with gradually decreasing diameters from bottom to top are evenly distributed on the inner side of the negative pressure cavity 501. The exhaust pipe 502 has a constricted structure near the lower outlet, and the constricted part of the exhaust pipe 502 is connected to the negative pressure cavity 501. The exhaust pipe 502 has an air inlet 504 near the upper end, and the air inlet 504 is connected to an air pipe. A circular plug 15 is slidably connected inside the exhaust pipe 502, which is connected to the air pump. The height of the plug 15 is greater than the diameter of the air inlet 504. A magnet 16 is fixedly connected inside the plug 15 by a U-shaped bracket. The airflow entering the exhaust pipe 502 through the air inlet 504 flows downward through the gap between the magnet 16 and the side wall of the plug 15. An electromagnet 17 is correspondingly provided on the magnet 16. The electromagnet 17 is fixedly connected to the top of the exhaust pipe 502. A limit spring 18 is provided below the plug 15. The upper end of the limit spring 18 is fixedly connected to the plug 15, and the lower end of the limit spring 18 is fixedly connected to the exhaust pipe 502. The electromagnet 17, the power supply, and the regulating resistor 11 form a series circuit.

[0017] Working principle of the invention: In use, the melt is introduced into the melt inlet of the guide section 1. After entering the guide tube 10, the melt rapidly heats up under the heating action of the heater 9, reducing its viscosity and increasing its fluidity. The melt is then ejected from the lower end of the guide tube 10 to form a filament bundle. An air pump then draws air into the exhaust pipe 502 and ejects it through the lower port along the filament bundle axis. The airflow is used to cool and shape the filament bundle, and the direction of the airflow is aligned with the filament bundle axis. The lines are parallel to ensure the cooling effect. At the same time, when the airflow flows in the exhaust pipe 502, a negative pressure is formed at the constriction part of the exhaust pipe 502. The air below the drainage pipe 10 enters the exhaust pipe 502 from the air intake hole 503 through the negative pressure chamber 501 and is discharged. By drawing air from the area below the drainage pipe 10, the air pressure in the area below the drainage pipe 10 is lower than the ambient air pressure, forming a pressure difference that decreases as the air pressure gets closer to the drainage pipe 10. This reduces the pulling force of the wire at the lower end of the drainage pipe 10 and prevents the wire from being pulled before it is completely cooled and set.

[0018] As the temperature increases, the viscosity of the melt decreases, the melt flows faster, and the spinning rate increases. Conversely, as the temperature decreases, the viscosity of the melt increases, the melt flows slower, and the spinning rate decreases. During the melt flow, the friction between the melt and the side wall of the guide tube 10 causes the guide tube 10 to compress the positioning spring 14 and slide downward. Adjusting the contact point between the annular conductive sheet 13 and the regulating resistor 11, and adjusting the resistance value of the regulating resistor 11 in the circuit, adjusts the heating power of the heater 9. This creates a negative feedback mechanism between the heating power of the heater 9 and the spinning rate of the melt as it passes through the guide tube 10. A faster spinning rate triggers a decrease in the heating power of the heater 9, reducing the temperature of the melt inside the guide tube 10 and thus limiting the spinning rate. Conversely, a slower spinning rate triggers an increase in the heating power of the heater 9, increasing the temperature of the melt inside the guide tube 10 and thus accelerating the spinning rate. This allows for the regulation of the spinning rate and the maintenance of its stability. According to the principle that the greater the resistance in a series circuit, the smaller the current, the melt drives the guide tube 10 to slide while forming a feedback mechanism with the electromagnet 17. By adjusting the current, the magnetic force of the electromagnet 17 is adjusted. When the spinning speed increases, the current flowing into the electromagnet 17 decreases. Under the elastic force of the limiting spring 18, the plug 15 slides downward, increasing the air inlet 504, increasing the air intake, and increasing the airflow in the exhaust pipe 502, thus enhancing the cooling rate. Similarly, when the spinning speed decreases, the current flowing into the electromagnet 17 increases, and the force between the electromagnet 17 and the magnet block 16 increases. Under the elastic force of the limiting spring 18, the plug 15 slides upward, decreasing the air inlet 504, reducing the air intake, and decreasing the airflow in the exhaust pipe 502. By utilizing the feedback mechanism formed by the melt driving the guide tube 10 to slide and the electromagnet 17, the cooling airflow is adjusted by the spinning speed to ensure the cooling effect.

[0019] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A single-plate multi-hole composite spinneret assembly, characterized in that: The upper side of the spinneret assembly is provided with a flow guide, a filter and a distribution section in sequence. A melt inlet is opened in the middle of the upper side of the flow guide. The flow guide, filter and distribution section are connected to the spinneret assembly through a sealing structure to form a complete spinneret end. The spinneret assembly specifically includes a cooling sleeve, an outer sleeve, a spinneret, and a heating plate, all coaxially assembled. The spinneret and the heating plate are vertically fixed to the inner wall of the outer sleeve by bolts, and an insulating and heat-insulating layer is provided between the spinneret and the heating plate. The spinneret is located directly above the heating plate, and multiple cylindrical adjustment chambers penetrating the plate are arranged in a diamond array on the surface of the spinneret. A plate-shaped heater is embedded in the surface of the heating plate corresponding to the center of each adjustment chamber. All heaters form a diamond-shaped distribution array on the surface of the heating plate that is consistent with the arrangement of the adjustment chambers. A cooling sleeve is coaxially disposed directly below each of the heating elements, with the upper end face of the cooling sleeve tightly fitted to the bottom surface of the heating plate. Each of the regulating chambers is fitted with a vertically penetrating drainage tube, and the heating area of ​​the heater is directly opposite the upper end of the drainage tube to achieve localized radiant heating. Two strip-shaped regulating resistors are symmetrically embedded in the inner wall of each regulating chamber, and L-shaped conductive sheets are fixed on both sides of the bottom of the regulating chamber. The upper end of the conductive sheet is electrically connected to the top of the regulating resistor on the same side via a silver alloy wire. The lower ends of the conductive sheets on both sides are respectively connected to the positive and negative terminals of an external DC power supply via wires. One of the conductive sheets is also connected to the power supply terminal of the heater via a branch wire. The lower end of the drainage tube is machined into an inwardly tapered structure, and the upper outer wall of the drainage tube is integrally formed with an annular limiting protrusion. The outer side of the limiting protrusion is tightly covered with a copper annular conductive sheet, and the outer peripheral surface of the annular conductive sheet maintains sliding electrical contact with the inner sidewalls of the two adjusting resistors. Adjust the position of the annular conductive sheet by sliding the drainage tube up and down.

2. The spinneret assembly according to claim 1, characterized in that: The drainage tube is fitted with a spiral positioning spring. The upper end of the positioning spring is welded and fixed to the bottom surface of the limiting protrusion, and the lower end of the positioning spring is fixedly connected to the upper surface of the heating plate through a buckle structure. The positioning spring, in its natural state, maintains a constant contact pressure between the annular conductive plate of the drainage tube and the adjusting resistor.

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