Nonwoven fabric manufacturing apparatus and nonwoven fabric manufacturing method

Abstract

To provide a nonwoven fabric manufacturing apparatus and a nonwoven fabric manufacturing method which are ideal for the production of a large variety and small quantity of nonwoven fabrics, can easily switch resin materials, can suppress waste of materials, can reduce costs, can prevent generation of abnormal noise and poor supply of materials during production, and can easily and properly equalize the basis weight, fiber diameter, porosity, etc. of the nonwoven fabric.SOLUTION: The nonwoven fabric manufacturing apparatus includes: a die 2 having a nozzle row 21 for discharging a thermoplastic resin C in a molten state; resin supply means 3 for supplying the thermoplastic resin C to the die 2 in a molten state; hot air supply means 4 for supplying hot air to the thermoplastic resin discharged from the nozzle row 21 and stretching it into a fibrous shape; and a collector 5 for forming a nonwoven fabric by accumulating the fibrous thermoplastic resin on a conveyor belt 53, wherein the resin supply means 3 includes a cylinder 31 for storing the thermoplastic resin C; and a piston 32 for pushing the thermoplastic resin C in the cylinder 31 toward the die 2.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a meltblown nonwoven fabric manufacturing apparatus that discharges, stretches, and accumulates a thermoplastic resin in a molten state from a die to produce a nonwoven fabric, and a nonwoven fabric manufacturing method thereof.

Background Art

[0002] Conventionally, a resin supply stage having an extruder that extrudes a thermoplastic resin in a molten state, a filter that removes foreign matter, and a gear pump that continuously feeds a fixed amount of thermoplastic resin toward a die supplies the thermoplastic resin in a molten state to the die, and a meltblown nonwoven fabric manufacturing facility that generates a nonwoven fabric by supplying hot air to the thermoplastic resin extruded from the nozzle head of the die and stretching it into fibers is known (see, for example, Patent Document 1). Conventionally, a screw-type extruder that supplies a resin material or the like into a cylinder heated by a heater and melts the material while kneading it by the rotation of a screw and transfers it toward a nozzle has been used for the extruder of the thermoplastic resin.

[0003] The above screw-type extruder is generally designed as a device for continuously supplying a resin material and performing mass production, and is configured to sequentially feed the resin material introduced into the cylinder to the die by heating and melting it with a heater while rotating the screw.

[0004] On the other hand, for example, in the field of regenerative medicine, a bioabsorbable resin is used as a material for nonwoven fabrics. However, many of these bioabsorbable resins are still under development, extremely expensive, and often limited in the amount used. In addition, nonwoven fabrics used in the field of regenerative medicine are required to appropriately control and uniformize the fiber diameter, porosity, etc. of the nonwoven fabric in order to pursue an appropriate relationship with living tissues. In recent years, including other fields, there has been a tendency to produce such high-quality products in small quantities of multiple varieties.

[0005] When conducting multi-variety and small-batch production, if the above-mentioned screw-type extruder is used, when switching types, the resin material previously used remains in the extruder, and it is necessary to dispose of it or clean the screw, etc. There was a problem that waste of resin material and switching operation time became long. In addition, since the screw-type extruder does not come out until the inside is filled with a new resin material, a resin material more than the amount required for the original fibrillation is required. Thus, when conducting multi-variety and small-batch production with conventional devices, there were problems such as waste of materials and high costs.

[0006] In addition, in the above-mentioned screw-type extruder, depending on the conditions, there is a possibility of poor kneading, and there is also a concern that abnormal noise may occur because the resin material cannot be properly fed into the die, or poor supply of the resin material may occur. Furthermore, it is necessary to design the screw in a special shape in consideration of the physical properties of the resin material to be used, and the structure of the device inevitably becomes complicated.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] Therefore, in view of the above situation, what the present invention attempts to solve is to be optimal for multi-variety and small-batch production of non-woven fabrics, easy to switch resin materials, suppress waste of materials, reduce costs, and further, easily prevent the generation of abnormal noise and poor supply of materials during manufacturing, and provide a non-woven fabric manufacturing apparatus capable of easily and appropriately uniformizing the basis weight, fiber diameter, porosity, etc. of the non-woven fabric, and a method for manufacturing a non-woven fabric.

Means for Solving the Problems

[0009] The present invention provides a nonwoven fabric manufacturing apparatus including a die having a nozzle row for discharging a molten thermoplastic resin, a resin supply means for supplying the thermoplastic resin in a molten state to the die, a hot air supply means for supplying hot air to the thermoplastic resin discharged from the nozzle row to stretch it into a fibrous shape, and a collector for generating a nonwoven fabric by accumulating the fibrous thermoplastic resin on a conveyor belt. The resin supply means includes a cylinder for accommodating the thermoplastic resin and a piston for extruding the thermoplastic resin in the cylinder toward the die.

[0010] Here, it is preferable that the resin supply means includes a heating means for melting the thermoplastic resin accommodated in the cylinder.

[0011] Here, it is preferable that the cylinder is directly connected to the die.

[0012] Here, it is preferable that the resin supply means has an electric actuator for driving the piston at a constant speed.

[0013] Here, it is preferable that the inner diameter of the cylinder is 30 mm or less.

[0014] Here, it is preferable that a space portion for generating the nonwoven fabric is formed between the die and the collector, and a shielding plate for shielding the space portion from the outside is provided.

[0015] Here, it is preferable to further include a preforming means having a preforming die having an inner diameter smaller than the inner diameter of the cylinder, a heating portion for heating the pellet-shaped thermoplastic resin accommodated in the forming die to a temperature equal to or higher than the softening temperature, and a pressing portion for pressing the softened thermoplastic resin into a rod shape for preforming.

[0016] In addition, the non-woven fabric manufacturing method according to the present invention involves putting a certain amount of thermoplastic resin into a cylinder, using a piston to extrude a certain amount of the thermoplastic resin in the cylinder in a molten state toward a die, discharging the certain amount of the thermoplastic resin from a nozzle row of the die, supplying hot air to the certain amount of thermoplastic resin discharged from the nozzle row to stretch it into fibers, and accumulating the fibrous thermoplastic resin to produce a non-woven fabric.

[0017] Here, it is preferable to accommodate the pellet-shaped thermoplastic resin in a preform die having an inner diameter smaller than the inner diameter of the cylinder, heat the thermoplastic resin to a temperature equal to or higher than the softening temperature, pressurize the softened thermoplastic resin to preform it into a rod shape, and then put the rod-shaped preform into the cylinder.

Advantages of the Invention

[0018] According to the present invention, in the small-lot production of various types of non-woven fabrics, it is easy to switch resin materials, waste of materials can be suppressed, and cost reduction can be achieved. Also, unlike the case of using a screw-type extruder, there is no risk of poor kneading of materials, abnormal noise during feeding of the resin material, or poor supply of the resin material due to conditions, and the structure of the apparatus can be simplified.

[0019] Moreover, according to a non-woven fabric manufacturing apparatus in which the resin supply means includes a heating means for melting the thermoplastic resin accommodated in the cylinder, unlike the case of putting a thermoplastic resin heated to a molten state in a separate heating section into the cylinder, the inner wall surface of the cylinder is not adhered with the thermoplastic resin, and continuous feeding of the thermoplastic resin is possible.

[0020] Furthermore, when the cylinder is directly connected to the die, the cylinder can be easily removed from the die during resin change or the like, and its cleaning work can be easily performed. Also, unlike the case of connecting the cylinder to the die via a connecting pipe, no thermoplastic resin remains in the connecting pipe during resin change or the like, so waste of materials can be suppressed.

[0021] In addition, when the resin supply means has an electric actuator that drives the piston at a constant speed, it is possible to easily and surely prevent the driving speed of the piston from fluctuating and the discharge flow rate of the thermoplastic resin discharged from the die from becoming unstable, accurately control the discharge flow rate of the thermoplastic resin, and more appropriately uniformize the basis weight of the nonwoven fabric.

[0022] Furthermore, when the inner diameter of the cylinder is 30 mm or less, it is possible to easily and appropriately heat the thermoplastic resin accommodated in the cylinder and prevent the thermoplastic resin in an unmelted state from remaining in the central portion.

[0023] In addition, in the case where a shielding plate is provided to shield the space for forming the nonwoven fabric formed between the die and the collector from the outside, the molten thermoplastic resin discharged from the die is cooled by being affected by heat from the outside before being accumulated on the conveyor belt, resulting in insufficient adhesion force at the side edges of the nonwoven fabric, or the basis weight at the side edges of the nonwoven fabric is insufficient due to the influence of the air flow flowing in from the outside. This can be effectively prevented.

[0024] Furthermore, according to a nonwoven fabric manufacturing apparatus and a nonwoven fabric manufacturing method configured to accommodate pellet-shaped thermoplastic resin in a preforming die having an inner diameter smaller than the inner diameter of the cylinder, heat the thermoplastic resin to a temperature equal to or higher than the softening temperature, pressurize the softened thermoplastic resin to preform it into a rod shape, and then input the rod-shaped preform into the cylinder, it is possible to smoothly accommodate an appropriate amount of thermoplastic resin in the cylinder without causing a problem that the thermoplastic resin adheres to the inner wall surface of the cylinder heated to a temperature equal to or higher than the melting temperature of the thermoplastic resin, thereby hindering subsequent input operations.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0026] Next, embodiments of the present invention will be described.

[0027] As shown in FIGS. 1 to 4, the nonwoven fabric manufacturing apparatus 1 according to the embodiment of the present invention includes a die 2 having a nozzle head 20 that extrudes a molten thermoplastic resin in a filament form, a resin supply means 3 that supplies the thermoplastic resin C in a molten state to the die 2, a hot air supply means 4 that supplies hot air to the thermoplastic resin (filamentous resin) D discharged in a filament form from a nozzle row 21 provided in the nozzle head 20 to stretch it into thin fibrous form, a collector 5 that accumulates the fibrous thermoplastic resin to produce a nonwoven fabric 50, and a winding means 6 that winds up the produced nonwoven fabric 50.

[0028] The die 2 supplies the thermoplastic resin C supplied by the resin supply means 3 to the nozzles of the nozzle head 20 It is a T-die that uniformly distributes toward the nozzle row 21. The nozzle row 21 is formed by arranging a plurality of nozzle holes side by side in a direction perpendicular to the cross section of the die 2 (a direction perpendicular to the plane of the paper in FIG. 2). Hot air outlets 22, 22 in the shape of slits that extend parallel to the nozzle row 21 are opened at positions adjacent to the front and rear (front and rear in the transport direction of the collector 5) with the nozzle row 21 interposed therebetween.

[0029] The die 2 is provided with a hot air outlet passage 23 that guides the hot air supplied from the hot air supply means 4 to the hot air outlet 22. In this embodiment, an example in which the nozzle row 21 is a single row is illustrated, but of course, a plurality of rows may be used. Further, the hot air outlet 22 may be provided with a row of a plurality of holes spaced apart from each other in addition to the slit shape, parallel to the nozzle row 21. The die 2 is also provided with a resin supply passage 24 that supplies the molten thermoplastic resin C supplied from the resin supply means 3 to the nozzle row 21, a pressure gauge 25 that detects the pressure of the thermoplastic resin C supplied to the nozzle row 21, and a thermometer 26 that detects the temperature of the thermoplastic resin C supplied to the nozzle row 21.

[0030] The filamentous resin D (see FIGS. 1 and 3) made of the thermoplastic resin discharged in a filamentous form from the nozzle row 21 of the nozzle head 20 is stretched by the high-speed hot air blown out from the hot air outlet 22 to become thin fibrous, and then is accumulated on the conveyor belt 53 of the collector 5 to form a sheet-like nonwoven fabric 50.

[0031] As shown in FIG. 2 and the like, the resin supply means 3 includes a cylinder 31 that stores a fixed amount of the thermoplastic resin C, a heating means such as a band heater externally fitted to the cylinder 31 or a coil-shaped heater (not shown), a piston 32 that extrudes the thermoplastic resin C in the cylinder 31 heated by this heating means to a molten state, and an electric actuator 30 that drives the piston rod 33 continuously provided above the piston 32 to move up and down at a constant speed.

[0032] The cylinder 31 has a cylinder body 34 with an inner diameter of 30 mm or less, and a resin supply portion 35 provided at the lower end thereof. A resin outlet passage 36 communicating with the resin supply passage 24 of the die 2 is formed in the resin supply portion 35. Further, a male screw portion that is screwed onto a female screw portion formed on the upper portion of the die 2 is formed on the lower outer peripheral surface of the resin supply portion 35. Then, when the male screw portion of the resin supply portion 35 is screwed onto the female screw portion of the die 2, a flow path for the molten resin is formed in which the resin outlet passage 36 of the cylinder 31 and the resin supply passage 24 of the die 2 are directly connected. In FIG. 2, reference numeral 27 is a packing for sealing the connection portion between the resin supply passage 24 and the resin outlet passage 36.

[0033] The electric actuator 30 drives the piston 32 so as to extrude the thermoplastic resin C in the cylinder 31 toward the die 2 by moving up and down at a constant speed along a support frame (not shown) while holding the upper end portion of the piston rod 33, and a known mechanism can be widely adopted as its drive mechanism.

[0034] As shown in FIG. 1, the hot air supply means 4 includes a compressor 41 that compresses and discharges air, a heater 42 that heats the compressed air discharged from the compressor 41, and a hot air supply pipe 43 that supplies hot air composed of the compressed air heated by the heater 42 to the hot air outlet passage 23 (see FIG. 3) of the die 2.

[0035] The collector 5 has a mesh conveyor belt 53 that is driven to convey by conveyor rollers 51 and 52, and a suction box 55 that sucks the air on the upper surface side of the conveyor belt 53 from the back surface side by the suction force of a suction blower 54. Then, the filamentous resin D discharged from the nozzle row 21 of the die 2 is stretched into thin fibers by the hot air blown out from the hot air outlet 22 and is accumulated on the conveyor belt 53 of the collector 5 to form a non-woven fabric 50. This non-woven fabric 50 is wound into a roll shape by a winding means 6 after passing through calendar rolls (not shown).

[0036] Between the lower surface of the die 2 and the upper surface of the collector 5, as shown in FIG. 3, a space portion 80 for forming a nonwoven fabric is formed. Further, on both the left and right side surfaces of the die 2, as shown in FIGS. 3 and 4, shielding plates 8 and 8 are attached to shield the space portion 80 for forming a nonwoven fabric from the outside, thereby suppressing the heat influence from the outside and the inflow of air.

[0037] FIG. 5 shows a preforming means 7 having a bottomed cylindrical preforming die 71, a heating portion composed of a band heater or a coil-shaped heater (not shown) described later for heating the pellet-shaped thermoplastic resin A accommodated in the preforming die 71 to a temperature equal to or higher than the softening temperature and preferably equal to or lower than the melting temperature, and a pressing portion 72 having a pressing piston for pressing the thermoplastic resin A in a softened state in the preforming die 71. The inner diameter of the preforming die 71 is formed to be a value smaller than the inner diameter of the cylinder 31 of the resin supply means 3, for example, about 25 mm, preferably about 14 mm.

[0038] Then, a certain amount of the thermoplastic resin A introduced into the preforming die 71 is heated and softened by the heating portion, and the softened state of the certain amount of the thermoplastic resin A is pressurized and integrated by the pressing portion 72. By integrating the certain amount of the thermoplastic resin A introduced into the preforming die 71 in this way, a rod-shaped preform B is formed in the preforming die 71. After the rod-shaped preform B is taken out from the preforming die 71, it is introduced into the cylinder 31 of the resin supply means 3.

[0039] Note that when the pellet-shaped thermoplastic resin A accommodated in the preforming die 71 is heated to a temperature higher than the melting temperature, the surface of the preform B becomes in a molten state and easily adheres to the inner surface of the preforming die 71 and the inner surface of the cylinder 31, making the take-out operation and the introduction operation of the preform B difficult. For this reason, the heating temperature by the heating portion of the preforming means 7 is preferably set to be equal to or higher than the softening temperature and equal to or lower than the melting temperature of the thermoplastic resin.

[0040] Hereinafter, a manufacturing method using the nonwoven fabric manufacturing apparatus 1 will be described.

[0041] First, a rod-shaped preform B made of a certain amount of thermoplastic resin A is formed by the preforming means 7. Then, this is put into the cylinder 31 of the resin supply means 3 and heated to a temperature equal to or higher than the melting temperature to make the thermoplastic resin C in a molten state. This molten thermoplastic resin C is extruded in a certain amount toward the die 2 by the piston 32, and the certain amount of thermoplastic resin is discharged in a filamentous form from the nozzle row 21 of the die 2. Then, hot air supplied from the hot air supply means 4 is blown onto the filamentous resin D discharged from the nozzle row 21 to stretch it into thin fibrous form, and the fibrous thermoplastic resin is accumulated on the conveyor belt 53 of the collector 5 to produce the non-woven fabric 50.

[0042] According to the above non-woven fabric manufacturing apparatus 1, when performing resin replacement to change the resin material used, there is no remaining previous resin as in a screw extruder, waste of materials can be suppressed, cleaning of the cylinder etc. is much easier compared to a screw extruder, and the resin replacement work can be performed quickly and easily. Also, there is no need to fill the inside with resin until it comes out as in a screw extruder, and the corresponding waste can be omitted, which is efficient. The structure is also simpler than that of a screw extruder, and the cost is reduced. Furthermore, there is no worry about abnormal noise occurring or poor material supply occurring as in a screw extruder, and it is easy to uniformly make the basis weight, fiber diameter, porosity, etc. of the non-woven fabric 50 appropriate and uniform.

[0043] In this embodiment, since the cylinder 31 is configured to be directly connected to the die 2 by screwing the female screw portion of the resin supply portion 35 provided at the lower end portion of the cylinder 31 into the female screw portion formed on the die 2, the cylinder 31 can be easily removed from the die 2 during resin replacement etc. and its cleaning work can be easily performed. Moreover, since there is no remaining thermoplastic resin in the connecting pipe during resin replacement etc. as in the case of connecting the cylinder 31 to the die 2 via a connecting pipe (not shown), waste of materials can be minimized.

[0044] Further, although it is possible to omit the electric actuator 30 that drives the piston 32 of the resin supply means 3 at a constant speed and drive the piston 32 by manual operation, for example, in order to more uniformly control the discharge flow rate of the thermoplastic resin C and make the basis weight of the nonwoven fabric 50 more uniform, it is preferable to adopt a configuration in which an electric actuator 30 that drives the piston 32 at a constant speed is provided as described above. Also, if the inner diameter of the cylinder 31 is too large, there is a risk that not all of the thermoplastic resin C introduced into the cylinder 31 can be heated to an appropriate temperature, and an unmelted thermoplastic resin may remain in the central part. Therefore, in order to heat the thermoplastic resin A introduced into the cylinder 31 to an appropriate temperature and supply all of it to the die 2 in an appropriate state, it is preferable to set the inner diameter of the cylinder 31 to 30 mm or less, preferably about 16 mm, as described above.

[0045] When the left and right side portions of the space portion 80 for generating the nonwoven fabric formed between the lower surface of the die 2 and the upper surface of the collector 5 are open, depending on the conditions, the molten thermoplastic resin discharged from the die 2 may be cooled by receiving heat from the outside before it accumulates on the conveyor belt 53, resulting in insufficient adhesion at the side edges of the nonwoven fabric 50, or the basis weight at the side edges of the nonwoven fabric 50 may be insufficient due to the influence of the air flow flowing in from the outside. Therefore, as shown in FIGS. 3 and 4, it is desirable to provide shielding plates 8, 8 that shield the space portion 80 for generating the nonwoven fabric formed between the lower surface of the die 2 and the upper surface of the collector 5 from the outside, and suppress the intrusion of heat and air flow from the outside, thereby suppressing the generation of ears.

[0046] Further, it is preferable to form a rod-shaped preform B by a preforming means 7 having a preforming die 71 with an inner diameter smaller than the inner diameter of the cylinder 31, a heating section for heating and softening the thermoplastic resin accommodated in the preforming die 71, and a pressing section 72 having a pressing piston for pressing the softened thermoplastic resin, and to configure it to be put into the cylinder 31 of the resin supply means 3. Thereby, there is an advantage that adhesion of the thermoplastic resin to the inner wall surface of the cylinder 31 can be prevented and a fixed amount of the thermoplastic resin C can be smoothly accommodated in the cylinder 31.

Example

[0047] After forming a rod-shaped preform B made of a predetermined amount of polypropylene resin by the above-described preforming means 7, it is supplied to the die 2 by the resin supply means 3 and discharged from the nozzle row 21, hot air is supplied thereto to stretch it into a fibrous shape, and the fibrous thermoplastic resin is collected by the collector to generate a non-woven fabric 50 having a width dimension of 150 mm and a thickness of 0.46 mm. An example will be described below.

[0048] As the raw material polypropylene resin, the product name "PWH00N" manufactured by Sun Allomer Co., Ltd. was used. Further, as the preforming means 7, a preforming die 71 having an inner diameter of 14 mm was used, 5 g of polypropylene resin was put therein, and it was heated at a temperature of 200°C for 10 minutes to form a rod-shaped preform B.

[0049] As the cylinder 31 of the resin supply means 3, one having an inner diameter of 16 mm and a cylinder length of 150 mm was used, and the extrusion speed by the piston 32 was set to 1 mm / second. The temperature of the hot air supplied by the hot air supply means 4 was set to 230°C, and the air volume of the hot air was set to 340 L / second. The temperature of the die 2 was set to 230°C, and the discharge distance of the molten resin, which is the separation distance between the die 2 and the upper surface of the conveyor belt of the collector 5, was set to 250 mm. The suction negative pressure of the collector 5 was set to 0.4 Mpa, and the collector speed was set to 1 m / minute.

[0050] When the non-woven fabric 50 was manufactured under the above conditions, 51.3 g / m2 A nonwoven fabric 50 having a basis weight, an average wire diameter of 10.6 μm, and a length of about 1 m was formed. Further, it was confirmed that the above nonwoven fabric 50 can be continuously formed by continuously supplying the rod-shaped preform B to the die 2 by the resin supply means 3.

[0051] Figs. 6 and 7 show a preforming means 9 capable of simultaneously forming a plurality of preforms B. This preforming means 9 includes a die body 91 in which five resin injection holes 90 are formed, an air vent block 92 attached to the lower end thereof, a suction blower (not shown) connected to an air vent hole 93 formed in the air vent block 92 via an air vent pipe (not shown), a heating part composed of a band heater 94 externally fitted to the die body 91 to heat it, a compression piston 95 inserted above the resin injection hole 90 to pressurize the thermoplastic resin A, an air vent plate 96 inserted below the resin injection hole 90, and a packing 97 for sealing the connection part between the die body 91 and the air vent block 92.

[0052] The band heater 94 uses, for example, a nichrome ribbon wire insulated with heat-resistant mica as a heating element and has its outer periphery covered and protected with a heat-resistant metal plate. Since its structure is well-known, a detailed description is omitted. A seal ring 98 is provided on the outer peripheral surface of the compression piston 95 to contact the inner peripheral surface of the resin injection hole 90 and seal the upper part of the resin injection hole 90. Further, a plurality of through holes 99 (see Fig. 6) are formed in the air vent plate 96 to communicate the resin injection hole 90 with the air vent hole 93 of the air vent block 92 while preventing the fall of the thermoplastic resin A.

[0053] In the above configuration, a predetermined amount of pellet-shaped thermoplastic resin A is charged and accommodated in each resin charging hole 90 of the mold body 91. With the compression piston 95 inserted into the upper part thereof, the band heater 94 is energized to heat the thermoplastic resin A to a temperature equal to or higher than its softening temperature and lower than its melting temperature, and the suction blower is operated to discharge the air in the resin charging hole 90 to the outside. As a result, the inside of each resin charging hole 90 becomes negative pressure and the compression piston 95 is suctioned downward, and the thermoplastic resin A in a softened state in each resin charging hole 90 is pressurized by the compression piston 95, and a plurality of rod-shaped preforms B are formed simultaneously. By sequentially charging these preforms B into the cylinder 31 of the resin supply means 3, a certain amount of thermoplastic resin is continuously supplied to the die 2.

[0054] FIGS. 8 and 9 show another embodiment of the nonwoven fabric manufacturing apparatus of the present invention. In this embodiment, a temperature measuring means 37 composed of a thermocouple or the like for measuring the temperature of the thermoplastic resin A charged in the cylinder 31 is detachably provided on the upper part of the cylinder 31. Further, a distribution plate 39 having a plurality of through holes 38 formed in the outer peripheral part is provided in the lower part of the cylinder 31.

[0055] When it is confirmed by the temperature measuring means 37 that the central part of the thermoplastic resin A has been heated to an appropriate temperature and has become a molten state, after removing the temperature measuring means 37 from the cylinder 31, the piston 32 is inserted into the cylinder 31 to extrude the thermoplastic resin C to the die 2, whereby the properly melted thermoplastic resin C can be supplied. Further, by providing the above-described distribution plate 39 in the lower part of the cylinder 31, there is an advantage that it is possible to prevent the molten thermoplastic resin C located in the central part of the cylinder 31 from being supplied to the die 2.

Explanation of symbols

[0056] 1 Nonwoven fabric manufacturing apparatus 2 Die 3 Resin supply means 4 Hot air supply means 5 Collector 6 Winding means 7,9 Preforming means 8 Masking plate 20 Nozzle head 21 Nozzle row 22 Hot air outlet 23 Hot air discharge passage 24 Resin supply passage 25 Pressure gauge 26 Thermometer 27 Packing 30 Electric actuator 31 Cylinder 32 Piston 33 Piston rod 34 Cylinder body 35 Resin supply section 36 Resin discharge passage 37 Temperature measuring means 38 Through hole 39 Distribution plate 41 Compressor 42 Heater 43 Hot air supply pipe 50 Non-woven fabric 51, 52 Conveyor roller 53 Conveyor belt 54 Suction blower 55 Suction box 71 Preforming mold 72 Pressing section 80 Space section 90 Resin inlet hole 91 Mold body 92 Air vent block 93 Air vent hole 94 Band heater (heating section) 95 Compression piston 96 Air vent plate 97 Packing 98 Seal ring 99 Through hole

Claims

1. A die having a nozzle array for discharging a molten thermoplastic resin, Resin supply means for supplying the thermoplastic resin in a molten state to the die, Hot air supply means for supplying hot air to the thermoplastic resin discharged from the nozzle array and stretching it into fibers, A collector for generating a non-woven fabric by accumulating the fibrous thermoplastic resin on a conveyor belt, comprising: The resin supply means has a cylinder for accommodating the thermoplastic resin and a piston for extruding the thermoplastic resin in the cylinder toward the die. A non-woven fabric manufacturing apparatus.

2. The non-woven fabric manufacturing apparatus according to claim 1, wherein the resin supply means includes heating means for melting the thermoplastic resin accommodated in the cylinder.

3. The non-woven fabric manufacturing apparatus according to claim 1, wherein the cylinder is directly connected to the die.

4. The non-woven fabric manufacturing apparatus according to claim 1, wherein the resin supply means has an electric actuator for driving the piston at a constant speed.

5. The non-woven fabric manufacturing apparatus according to claim 1, wherein the inner diameter of the cylinder is 30 mm or less.

6. The non-woven fabric manufacturing apparatus according to claim 1, wherein a space portion for generating the non-woven fabric is formed between the die and the collector, and a shielding plate for shielding the space portion from the outside is provided.

7. A preforming die having an inner diameter smaller than the inner diameter of the cylinder, A heating unit for heating the pellet-shaped thermoplastic resin accommodated in the forming die to a temperature equal to or higher than the softening temperature, The non-woven fabric manufacturing apparatus according to claim 1, further comprising preforming means having a pressing unit for pressing the softened thermoplastic resin into a rod shape for preforming.

8. Put a certain amount of thermoplastic resin into the cylinder, Extrude a certain amount of the thermoplastic resin in the cylinder in a molten state toward the die by a piston, Discharge the certain amount of the thermoplastic resin from the nozzle array of the die, A non-woven fabric manufacturing method in which hot air is supplied to the certain amount of thermoplastic resin discharged from the nozzle array to stretch it into fibers, and the fibrous thermoplastic resin is accumulated to produce a non-woven fabric.

9. The pellet-shaped thermoplastic resin is accommodated in a preforming die having an inner diameter smaller than the inner diameter of the cylinder, the thermoplastic resin is heated to a temperature equal to or higher than the softening temperature, and the softened thermoplastic resin is pressed into a rod shape for preforming. Then, the rod-shaped preform is put into the cylinder. The non-woven fabric manufacturing method according to claim 8.

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