JP2019173217A - Apparatus for manufacturing reticular structure and method for manufacturing reticular structure - Google Patents

Abstract

To provide an apparatus and a method for manufacturing a reticular structure, which generate little cooling irregularities in a thickness direction of the reticular structure when the reticular structure is cooled, and has sufficient durability.SOLUTION: There is provided an apparatus comprising: a nozzle 10 having a discharge hole 11 for extruding a molten thermoplastic resin in a line shape; a water tank 20 arranged below the nozzle 10; a conveying device 30 which is provided in the water tank 20 and conveys a reticular structure 60 having a linear resin 12; and a gas release device 40 which is provided in the water tank 20 and releases a gas.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an apparatus for manufacturing a network structure and a method for manufacturing the network structure.

  Currently, net-like structures are being widely used as cushioning materials used in furniture, bedding such as beds, and seats for vehicles such as trains, automobiles, and motorcycles. The network structure has the same durability as the foamed-crosslinked urethane, has excellent moisture permeability and air permeability, and has an advantage that it is hard to be steamed because of low heat storage. Furthermore, since it consists of a thermoplastic resin, there are advantages that it is easy to recycle, there is no worry about residual chemicals, and it is environmentally friendly.

  As a production apparatus for a network structure, a pair having a plurality of extrusion holes for extruding and lowering a molten thermoplastic resin as a filament, a water tank for cooling the aggregate of the filament, and a pair below the extrusion hole Conveyors that are provided opposite to each other and that have endless members that are provided around the gap, and water that passes through the gap from the vicinity of the jet holes that are provided in an inner region of the conveyor and that jet cooling water from the gap toward the aggregate. A forced convection member including at least one of the suction holes for sucking the liquid, and the aggregate is taken up by a conveyor at a speed slower than the descending speed of the filament, and cooled in the water tank, so that the aggregate becomes a three-dimensional network structure. There is a three-dimensional network-structure manufacturing apparatus (see, for example, Patent Document 1).

  In addition, as a method for producing a network structure, an extrusion step in which molten thermoplastic resin is extruded downward as a plurality of filaments and lowered, and a collection of filaments in which the filaments contact the water surface or descend are sandwiched. A pair of guide members facing each other or a conveyor facing below the guide members, the loops are entangled irregularly, and the entangled portion is thermally welded, and the assembly is sandwiched by the conveyor A take-off step of taking the water into the water at a speed slower than the descending speed of the wire, and an endless member provided around the conveyor has a gap, and from the inner area of the conveyor toward the take-up area sandwiched between the pair of conveyors Forced convection of water occurs by ejecting cooling water or sucking water through the gap from the take-up area to the inner area of the conveyor, and collects in parallel with the take-off step The is method of producing a three-dimensional net-like structure characterized by comprising a cooling step of cooling in water (e.g., see Patent Document 1).

Japanese Patent Laying-Open No. 2015-155588

  However, the manufacturing apparatus and the manufacturing method of the network structure as disclosed in Patent Document 1 jet the cooling water toward the network structure when manufacturing the network structure, and the surface portion of the network structure directly hit with the cooling water. There is a difference in the degree of cooling between the inside and the inside where the cooling water is not applied, and cooling spots are generated in the thickness direction of the network structure. When there are cooling spots in the production of a network structure, the internal repeated compression residual strain that was insufficiently cooled is large, the hardness retention after repeated compression is small, and the durability of the network structure is extremely inferior. There is a problem that it ends up.

  The present invention was devised to solve the above-described problems of the prior art, and its purpose is to cool the network structure in the thickness direction when the network structure is cooled during the manufacture of the network structure. An object of the present invention is to provide a manufacturing apparatus and a manufacturing method for a net-like structure which is less likely to cause spots and has sufficient durability.

  The network structure manufacturing apparatus of the present invention that has solved the above problems includes a nozzle having a discharge hole for extruding a molten thermoplastic resin as a line, a water tank disposed below the nozzle, and a water tank. It is provided, It has a conveyance device which conveys the network-like structure which has resin of a line, and is provided in a water tank, It has a gas discharge device which discharges gas, It is characterized by the above-mentioned. .

  In the network structure manufacturing apparatus of the above invention, the gas release device is preferably provided below the transfer device.

  In the network structure manufacturing apparatus of the above invention, the gas discharge device preferably has a discharge hole for discharging a gas, and the normal direction of the discharge hole is preferably directed to the water surface of the water tank.

  In the network structure manufacturing apparatus according to the above invention, the transport device includes at least a first transport device and a second transport device, and there is a network structure between the first transport device and the second transport device, and the gas It is preferable that the discharge device has a discharge hole for discharging a gas, and the normal direction of the discharge hole is directed to a network structure between the transfer devices.

  In the network structure manufacturing apparatus according to the invention, it is preferable that the amount of gas released from the gas releasing device increases as the amount of resin extruded from the nozzle increases.

  In the network structure manufacturing apparatus of the above invention, the amount of gas released by the gas discharge device is preferably increased as the speed of the transfer device increases.

  In the network structure manufacturing apparatus according to the invention, it is preferable that the transport device has a mesh belt and a driving roller.

  In the network structure manufacturing apparatus according to the above invention, the network structure pulling device for pulling the network structure is provided on one side of the water tank, and the transport device includes at least a first transport device and a second transport device. The gas discharge device is preferably arranged on the network structure pulling device side of the vertical plane including the midpoint between the first transfer device and the second transfer device.

  In the network structure manufacturing apparatus according to the invention described above, the gas release device includes at least a first gas release device and a second gas release device, and the transfer device includes at least a first transfer device and a second transfer device. The first gas release device is preferably provided below the first transfer device in the vertical direction, and the second gas release device is preferably provided below the second transfer device in the vertical direction.

  In addition, the method for producing a network structure according to the present invention that has solved the above problems includes a step of extruding a molten thermoplastic resin as a filament, and a network having the filament resin by a conveying means. And a step of discharging gas into the water in the water tank by the gas discharge device.

  According to the present invention, the gas releasing device provided in the water tank releases the gas, so that convection can be caused in the water in the water tank, and the surface portion and the inside of the network structure can be easily cooled uniformly. In addition, it is difficult to generate cooling spots in the thickness direction of the network structure, and a network structure with sufficient durability can be manufactured.

The side view of the network-structure manufacturing apparatus in embodiment of this invention is represented.

  Hereinafter, the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the illustrated examples, and may be implemented with appropriate modifications within a range that can be adapted to the purpose described above and below. Any of these may be included in the technical scope of the present invention.

  A network structure manufacturing apparatus according to the present invention is provided in a nozzle having a discharge hole for extruding a molten thermoplastic resin as a line, a water tank disposed below the nozzle, and the water tank. It has the conveyance apparatus which conveys the net-like structure which has resin, and the gas discharge | release apparatus which is provided in the water tank and discharge | releases gas, It is characterized by the above-mentioned.

  The network structure of the present invention has a three-dimensional random loop joining structure in which a linear resin made of a thermoplastic resin is twisted to form a random loop, and the respective loops are brought into contact with each other in a molten state. It is a structure.

  FIG. 1 is a side view of a network structure manufacturing apparatus according to an embodiment of the present invention. The network structure manufacturing apparatus 1 includes a nozzle 10, a water tank 20, a transfer device 30, and a gas release device 40.

  The nozzle 10 has a discharge hole 11 for extruding a molten thermoplastic resin as a line. That is, the linear resin 12 is formed by extruding the thermoplastic resin melted by heating from the discharge hole 11 of the nozzle 10.

  The discharge holes 11 of the nozzle 10 may be arranged in one row, but are preferably in a plurality of rows. Since the nozzle 10 has the plurality of discharge holes 11, a plurality of linear resin 12 can be formed at the same time, and the production efficiency of the network structure 60 can be increased. The number of discharge holes 11 provided in the nozzle 10 can be adjusted according to the hardness and cushioning properties of the network structure 60 to be manufactured.

  The cross-sectional shape of the outlet of the discharge hole 11 is not particularly limited, and examples thereof include a circle, an ellipse, and a polygon. In particular, the cross-sectional shape of the outlet of the discharge hole 11 is preferably circular or elliptical. When the discharge hole 11 is configured in this manner, the cross-sectional shape of the resin 12 of the filaments extruded from the discharge hole 11 is also circular or elliptical, and when the above-described three-dimensional random loop bonding structure is formed, By increasing the area where the linear resins 12 are in contact with each other, it is possible to manufacture the network structure 60 having high elasticity and durability.

  Further, the cross-sectional shape of the linear resin 12 extruded from the discharge hole 11 may be solid or hollow. In order to make the cross-sectional shape of the resin 12 of the filaments hollow, for example, a configuration having a mandrel such as a mandrel inside the discharge hole 11 may be used. Specifically, the cross-sectional shape of the outlet of the discharge hole 11 is a so-called C-type nozzle in which the inner side and the outer side of the discharge hole 11 are partially communicated, or a bridge is provided in the discharge hole 11 so that the discharge hole 11 is formed. A so-called three-point bridge nozzle or the like divided in the circumferential direction can be used.

  The length in the major axis direction of the cross-sectional shape of the outlet of the discharge hole 11 is preferably 0.1 mm or more, more preferably 0.5 mm or more, and further preferably 1.0 mm or more. By setting the lower limit value of the length in the major axis direction of the cross-sectional shape of the outlet of the discharge hole 11 in this way, the network structure 60 is improved in durability, and the network structure 60 can withstand repeated compression. Can do. Further, the length in the major axis direction of the cross-sectional shape of the outlet of the discharge hole 11 is preferably 10 mm or less, more preferably 7 mm or less, and further preferably 5 mm or less. By setting the upper limit value of the length in the major axis direction of the cross-sectional shape of the outlet of the discharge hole 11 in this way, the network structure 60 with good cushioning properties can be manufactured.

  When the nozzle 10 has a plurality of discharge holes 11, the size of the cross-sectional shape of the outlet of each discharge hole 11 may be the same or different. If the size of the cross-sectional shape of the outlets of all the discharge holes 11 included in the nozzle 10 is the same, the network structure 60 in which the thickness of the resin 12 of the filaments is uniform can be obtained. Further, for example, when the size of the cross-sectional shape of the outlet of the discharge hole 11 at the center of the nozzle 10 is made smaller than the size of the cross-sectional shape of the outlet of the discharge hole 11 at the outer peripheral portion, the line inside the reticulated structure 60 is obtained. Since the resin 12 in the strip is thinner than the resin 12 in the strip on the surface portion of the network structure 60, the internal temperature of the network structure 60 is likely to be lower than the surface portion, and the cooling structure is less likely to cause cooling spots. The body 60 can be manufactured.

  Examples of the thermoplastic resin extruded from the discharge hole 11 include polyester-based thermoplastic elastomer, polyolefin-based thermoplastic elastomer, polystyrene-based thermoplastic elastomer, polyurethane-based thermoplastic elastomer, polyamide-based thermoplastic elastomer, ethylene vinyl acetate copolymer, and the like. Is mentioned. In particular, the thermoplastic resin preferably contains at least one of a polyester-based thermoplastic elastomer, a polyolefin-based thermoplastic elastomer, and a polystyrene-based thermoplastic elastomer. When the thermoplastic resin contains at least one of a polyester-based thermoplastic elastomer, a polyolefin-based thermoplastic elastomer, and a polystyrene-based thermoplastic elastomer, processability is improved and the production of the network structure 60 is facilitated. Moreover, it is more preferable that the thermoplastic resin contains a polyester-based thermoplastic elastomer. Since the thermoplastic resin contains the polyester-based thermoplastic elastomer, the repeated compression residual strain can be reduced, the hardness retention after repeated compression can be increased, and a highly durable network structure 60 is manufactured. be able to.

  The water tank 20 is disposed below the nozzle 10 and is configured to receive the linear resin 12 extruded from the discharge hole 11 of the nozzle 10. The water tank 20 has water for cooling the linear resin 12 extruded from the discharge hole 11 of the nozzle 10. The linear resin 12 extruded from the discharge hole 11 of the nozzle 10 forms a random loop by landing on the water surface in the water tank 20 and twisting, and comes into contact with adjacent random loops in a molten state. A structure in which random loops are joined in a three-dimensional direction is formed and simultaneously cooled by water to fix the structure. In this way, the network structure 60 is obtained.

  The conveyance device 30 is provided in the water tank 20 and conveys the network structure 60 having the linear resin 12. That is, the transport device 30 transports the network structure 60 having the linear resin 12 that is pushed out from the discharge hole 11 of the nozzle 10 and received in the water tank 20 in the water tank 20. The transport device 30 preferably transports the network structure 60 from the water surface of the water tank 20 toward the bottom of the water tank 20.

  The kind of the conveying apparatus 30 is not specifically limited, For example, conveyors, such as a belt conveyor, a net conveyor, a slat conveyor, are mentioned. Details of the transport device 30 will be described later.

  The gas discharge device 40 is provided in the water tank 20 and discharges gas. The gas discharged from the gas discharge device 40 is preferably a gas compressed by a device (not shown) for compressing the gas. When the gas release device 40 releases gas in the water in the water tank 20, convection can be generated in the water in the water tank 20. When convection occurs in the water in the water tank 20, not only the water in the vicinity of the surface portion of the network structure 60 in the water tank 20 but also the water in the network structure 60 is moved through the gaps in the network structure 60. And new water is supplied. Therefore, both the surface part and the inside of the network structure 60 in the water tank 20 can be uniformly cooled, and cooling spots are less likely to occur. By preventing the occurrence of cooling spots, it is possible to prevent an increase in repeated compression residual strain due to insufficient cooling and a decrease in hardness retention after repeated compression in the production of the network structure 60, and durability. A high network structure 60 can be manufactured. Examples of the gas include air, oxygen gas, nitrogen gas, and the like, and air is preferable.

  The gas discharge device 40 is preferably provided below the transport device 30. Since the water in the vicinity of the water surface where the linear resin 12 extruded from the discharge hole 11 of the nozzle 10 comes into contact with the water in the water tank 20 becomes the highest temperature, the gas discharge device 40 is provided below the transport device 30. Thus, the water below the conveying device 30 that is lower in temperature than the water near the water surface can be fed into the resin 12 in the vicinity of the water surface, and the resin 12 in the vicinity of the water surface can be efficiently cooled. it can. The gas discharge device 40 may be provided between the lower end of the transfer device 30 and the bottom of the water tank 20, or may be provided at the bottom of the water tank 20.

  The gas discharge device 40 has a discharge hole 43 for discharging a gas, and the normal direction of the discharge hole 43 is preferably directed to the water surface of the water tank 20. The normal line of the discharge hole 43 refers to a line perpendicular to the surface including the opening of the discharge hole 43. Since the normal direction of the discharge hole 43 is directed to the water surface of the water tank 20, water convection can be caused from the vicinity of the gas discharge device 40 toward the water surface where the water temperature is high, and the network structure 60 is efficiently cooled. Can be done automatically. In the case where the gas discharge device 40 has a plurality of discharge holes 43, it is preferable that the normal direction of at least one discharge hole 43 is directed to the water surface of the water tank 20.

  The number of discharge holes 43 included in the gas discharge device 40 may be one or plural. If the number of the discharge holes 43 is one, it becomes easy to adjust the direction of the gas discharged from the discharge holes 43. Further, if the number of the discharge holes 43 is plural, the gas discharged from the discharge holes 43 can be diffused, and the water in the water tank 20 can be greatly convected, thereby improving the cooling efficiency of the network structure 60. be able to.

  Further, as will be described later, the transport device 30 includes at least a first transport device 31 and a second transport device 32, and a net-like structure 60 is provided between the first transport device 31 and the second transport device 32. In this case, it is also preferable that the normal direction of the discharge hole 43 is directed to the network structure 60 located between the transfer devices 30. Since the normal direction of the discharge hole 43 is directed to the network structure 60 located between the transfer devices 30, it becomes easier to feed water into the network structure 60, and cooling tends to be insufficient. It becomes easy to cool the inside of 60.

  More preferably, the normal direction of the discharge hole 43 faces the water surface of the water tank 20 and the net-like structure 60 located between the transfer device 30. Since the discharge holes 43 are configured in this way, convection of water can be generated from the gas discharge device 40 through the inside of the network structure 60 toward the water surface of the water tank 20, and the network structure 60. Cooling spots are less likely to occur in the thickness direction.

It is preferable that the amount of gas discharged from the gas discharge device 40 increases as the amount of resin pushed out from the nozzle 10 increases. That is, the volume (m ³ / min) of gas discharged from the gas discharge device 40 (measured value at 1 atm and normal temperature) and the extrusion amount (g / min) of the resin extruded from the nozzle 10 are linked. Is preferred. For example, when the amount of the resin 12 of the filaments extruded from the nozzle 10 is increased in order to increase the resilience of the network structure 60, the temperature near the water surface of the water tank 20 tends to become higher. Cooling efficiency is deteriorated, and the inside of the network structure 60 is not easily cooled, and cooling spots are easily generated in the thickness direction of the network structure 60. Therefore, the convection of water in the water tank 20 is increased by increasing the gas discharge amount of the gas discharge device 40 with the increase in the amount of the linear resin 12 extruded from the nozzle 10. Cooling efficiency can be increased and cooling spots can be prevented.

It is more preferable that the volume (m ³ / min) of gas released from the gas release device 40 (measured value at 1 atm and normal temperature) is proportional to the extrusion amount (g / min) of the resin from the nozzle 10. . Since the volume of the gas discharged from the gas discharge device 40 and the extrusion amount of the resin from the nozzle 10 are in such a relationship, the cooling efficiency of the network structure 60 can be further increased, and cooling spots occur. It becomes difficult.

It is also preferable that the amount of gas released by the gas release device 40 increases as the speed of the transfer device 30 increases. That is, it is preferable that the volume (m ³ / min) of gas discharged from the gas discharge device 40 (measured value at 1 atm and normal temperature) and the transport speed of the network structure 60 by the transport device 30 are linked. When the speed of the transfer device 30 is increased for the purpose of reducing the density of the network structure 60 in order to reduce the hardness of the network structure 60, the next step is performed while the inside of the network structure 60 is not sufficiently cooled. There is a possibility that the network structure 60 having a large internal repeated compression residual strain, a low hardness retention after repeated compression, and an inferior durability will be obtained. Therefore, as the speed of the transfer device 30 increases, the amount of gas released from the gas release device 40 is increased, thereby increasing the convection of water in the water tank 20 and increasing the cooling efficiency of the network structure 60. Not only the surface portion of the structure 60 but also the inside can be sufficiently cooled.

It is more preferable that the volume (m ³ / min) of gas released from the gas release device 40 (measured value at 1 atm and normal temperature) is proportional to the speed (m / min) of the transfer device 30. Since the volume of the gas discharged from the gas discharge device 40 and the speed of the transfer device 30 are in such a relationship, the cooling efficiency of the network structure 60 can be further improved and the occurrence of cooling spots can be prevented. it can.

Further, it is more preferable that the amount of gas discharged from the gas discharge device 40 increases as the amount of resin pushed out from the nozzle 10 increases and increases as the speed of the transfer device 30 increases. That is, the volume (m ³ / min) of gas released from the gas releasing device 40 (measured value at 1 atm and normal temperature) is the amount of resin extruded from the nozzle 10 (g / min) and the speed of the conveying device 30. More preferably, it is proportional to (m / min). Since the amount of the gas released from the gas discharge device 40 is as described above, for example, the amount of the linear resin 12 extruded from the nozzle 10 is increased for the purpose of increasing the productivity of the network structure 60. Even when the speed of the transfer device 30 is increased, the reticular structure 60 can be sufficiently cooled by increasing the convection of the water in the water tank 20, and cooling spots in the thickness direction of the reticular structure 60 are less likely to occur. be able to.

  It is preferable that the upper end part of the conveying apparatus 30 exists above the water surface of the water tank 20. By arranging the transport device 30 in this way, when the linear resin 12 pushed out from the discharge hole 11 of the nozzle 10 comes into contact with the water in the water tank 20, the linear resin 12 is on the water surface. It is possible to prevent the network structure 60 from becoming excessively thick by preventing free movement.

  The conveying device 30 preferably has a conveyor belt 33. Conveyor belt 33 is a net conveyor belt meshed by continuously weaving or weaving rubber or resin flat belts or metal wires, or attaching metal plates to conveyor chains continuously. Slat conveyor belts.

  Among these, the conveyor belt 33 is preferably a net conveyor belt because it has good gripping performance and excellent water passage performance. That is, the conveying device 30 is preferably a net conveyor conveying device having a mesh belt and a driving roller 34. Since the transport device 30 is configured in this way, water and gas can pass through the transport device 30, and therefore the transport device 30 is unlikely to interfere with the convection of the water in the water tank 20 by the gas discharge device 40, and is a net-like shape. The cooling efficiency of the structure 60 can be increased.

  The conveyor belt 33 is preferably endless. Since the conveyor belt 33 is configured to be endless, the endless conveyor belt 33 can be rotated without interruption by the rotation of the driving roller 34, and the transport device 30 can be continuously operated. Transport can be performed efficiently.

  It is preferable that there are a plurality of driving rollers 34 provided at the upper and lower portions inside the endless conveyor belt 33. That is, it is preferable that the upper drive roller 34 a is provided at the upper part inside the conveyor belt 33 and the lower drive roller 34 b is provided at the lower part inside the conveyor belt 33. Since the driving roller 34 is configured in this way, it is difficult for the conveyor belt 33 to bend, and the rotation of the driving roller 34 can prevent the conveyor belt 33 from spinning and causing the conveyance device 30 to malfunction.

  The transport device 30 is composed of at least a first transport device 31 and a second transport device 32, and it is preferable that the network structure 60 is present between the first transport device 31 and the second transport device 32. Since the transport device 30 is configured in this manner, the mesh structure 60 can be transported in a state of being sandwiched between the first transport device 31 and the second transport device 32, so that the surface is prepared. The network structure 60 having a constant thickness can be obtained.

  The distance between the lower drive roller 34b of the first transport device 31 and the lower drive roller 34b of the second transport device 32 is the distance between the upper drive roller 34a of the first transport device 31 and the upper drive roller 34a of the second transport device 32. Is preferably smaller. That is, it is preferable that the distance between the 1st conveying apparatus 31 and the 2nd conveying apparatus 32 is smaller in the lower part than the upper part, and becomes narrow as it goes to the lower part. Since the transport device 30 is configured in this manner, the network structure 60 can be sandwiched between the lower portions of the transport device 30 and the linear resin 12 and the network structure 60 can be easily drawn into the water tank 20. It becomes easy to cool the network structure 60.

  The network structure manufacturing apparatus 1 preferably includes a network structure pulling apparatus 50 that pulls the network structure 60 and pulls it up from the water tank 20. Since the network structure manufacturing apparatus 1 includes the network structure pulling device 50, the network structure 60 is automatically pulled up from the water tank 20 after the network structure 60 is cooled, and the network structure 60 is dried. Since it can move, the productivity of the net-like structure 60 can be raised.

  A network structure pulling device 50 that pulls the network structure 60 is provided on one side of the water tank 20, and the transport device 30 includes at least a first transport device 31 and a second transport device 32, and gas It is preferable that the discharge device 40 is disposed closer to the network structure pulling device 50 than the vertical plane p1 including the midpoint P1 between the first transfer device 31 and the second transfer device 32. In the aquarium 20, since the mesh structure 60 exists on the mesh structure pulling device 50 side of the vertical plane p1, the vertical plane p1 is located on the vertical plane p1 on the opposite side of the mesh structure pulling device 50 side. In order to cool the network structure 60 efficiently, it is preferable to cause more convection of water toward the network structure pulling device 50 side. Therefore, by arranging the gas release device 40 in this way, convection can be caused more efficiently with respect to the water in the vicinity of the network structure 60, and the cooling efficiency of the network structure 60 can be improved. .

  The gas release device 40 includes at least a first gas release device 41 and a second gas release device 42, and the transfer device 30 includes at least a first transfer device 31 and a second transfer device 32. The first gas discharge device 41 is preferably provided below the first transfer device 31 in the vertical direction, and the second gas discharge device 42 is preferably provided below the second transfer device 32 in the vertical direction. By arranging the first gas release device 41 and the second gas release device 42 in this way, convection of water can be generated on both sides of the network structure 60, not only in the vicinity of the network structure 60, Water in the entire water tank 20 can be moved, and the cooling efficiency of the network structure 60 can be further improved.

  The normal direction of the discharge hole 43 of the first gas discharge device 41 may be the same as or different from the normal direction of the discharge hole 43 of the second gas discharge device 42. For example, the normal direction of the discharge hole 43 of the first gas discharge device 41 is the vertical direction toward the water surface, and the normal direction of the discharge hole 43 of the second gas discharge device 42 is also the vertical direction. In the direction toward the water surface, convection of water can be caused equally on both sides of the net-like structure 60 in the water tank 20, and convection is generated in a balanced manner between the first gas release device 41 and the second gas release device 42. be able to. Further, if the normal direction of the discharge hole 43 of the first gas discharge device 41 and the normal direction of the discharge hole 43 of the second gas discharge device 42 are different, the first gas discharge device 41 and the second gas discharge device. 42, water convection can be caused in different places, and convection can be preferentially caused in places where convection is desired.

  As shown in FIG. 1, the normal direction of the discharge hole 43 of the first gas discharge device 41 and the normal direction of the discharge hole 43 of the second gas discharge device 42 are the center of the upper drive roller 34 a of the first transport device 31. It is also preferable to be between the point and the center point of the upper drive roller 34 a of the second transport device 32. Since the first gas release device 41 and the second gas release device 42 are configured in this manner, the filaments pushed out from the discharge hole 11 of the nozzle 10, which is the place where the water temperature is highest in the water tank 20. Thus, convection can be efficiently generated at the place where the resin 12 and the water in the water tank 20 are in contact with each other, and the network structure 60 can be efficiently cooled.

  The distance from the first gas discharge device 41 to the bottom of the water tank 20 may be the same as or different from the distance from the second gas discharge device 42 to the bottom of the water tank 20. If the distance from the first gas discharge device 41 to the bottom of the water tank 20 is the same as the distance from the second gas discharge device 42 to the bottom of the water tank 20, the convection caused by the first gas discharge device 41 and the second gas discharge The convection generated by the device 42 can be of the same level, and the first gas releasing device 41 and the second gas releasing device 42 can generate convection in the water tank 20 with a good balance.

  Further, the distance from the first gas discharge device 41 to the bottom of the water tank 20 is different from the distance from the second gas discharge device 42 to the bottom of the water tank 20, and on the side where the net-like structure pulling device 50 is provided. When the first gas release device 41 is arranged and the distance from the first gas release device 41 to the bottom of the water tank 20 is larger than the distance from the second gas discharge device 42 to the bottom of the water tank 20, the first gas Since the discharge device 41 is provided at a location close to the resin 12 of the filaments, convection can be largely caused near the network structure 60, and the cooling efficiency of the network structure 60 can be improved.

  The amount of gas released by the first gas release device 41 may be the same as or different from the amount of gas released by the second gas release device 42. If the amount of gas released by the first gas release device 41 is the same as the amount of gas released by the second gas release device 42, the first gas release device 41 and the second gas release device 42 are in the water tank 20. The same level of convection can be generated in the water, and convection can be generated in a well-balanced manner in the water tank 20.

  In addition, the amount of gas released by the first gas release device 41 is different from the amount of gas released by the second gas release device 42, and the first gas release is performed on the side where the network structure pulling device 50 is provided. If the device 41 is disposed and the amount of gas released by the first gas release device 41 is larger than the amount of gas released by the second gas release device 42, the first gas release device 41 closer to the network structure 60 is obtained. The generated water convection can be increased, and the network structure 60 can be efficiently cooled.

  The water in the water tank 20 may be discharged, and new low-temperature water may be supplied to the water tank 20. Although not shown in the drawings, the water in the water tank 20 may be discharged by so-called overflow, in which water is discharged from a pipe or the like provided in the upper part of the water tank 20. Specifically, for example, new low-temperature water is supplied from the lower part of the water tank 20 to the water tank 20 to overflow the water whose temperature has increased.

  A method for producing a network structure according to the present invention includes a step of extruding a molten thermoplastic resin into a line, a step of conveying a network structure having a resin of a line in a water tank by a conveying means, and a gas releasing device And a step of releasing a gas into the water in the water tank.

  The thermoplastic resin used as the material of the network structure is heated and melted, and the resin is extruded so as to form a filament. In order to make the resin into a filament, the molten thermoplastic resin may be extruded from a nozzle or the like having a discharge hole.

  The extruded linear resin is received in a water tank in which water is stored. A structure in which a random loop is formed by landing and twisting the resin of the filament on the water surface in the water tank, and the adjacent random loops are in contact with each other in a molten state, thereby joining the random loops in a three-dimensional direction. At the same time, the structure is fixed by cooling with water to form a network structure.

  The network structure is transported in the water tank by the transport means. The conveying means preferably conveys the network structure downward from the water surface in the water tank. By transporting the net-like structure by the transport means in this way, the extruded linear resin is continuously formed into a sheet-like net-like structure, and has a size suitable as a cushioning material for bedding and seats. A network structure can be produced. As the conveying means, for example, a conveying device such as the aforementioned conveyor can be used.

  Gas is discharged into the water in the water tank by the gas discharge device. By releasing the gas in the water, convection is generated in the water in the water tank, and the hot water near the water surface moves to supply low-temperature water. As a result, the network structure is efficiently cooled so that not only the surface portion but also the inside of the network structure can be sufficiently cooled, cooling spots hardly occur, and a highly durable network structure is manufactured. Can do.

  The network structure after cooling can be produced by lifting the network structure from the water tank and drying it. Before and after drying the network structure, it is preferable to perform a pseudo crystallization treatment in which heating is performed for a predetermined time at a temperature lower than the melting point of the resin used for the material of the network structure. By performing pseudo-crystallization treatment on the network structure, the durability of the network structure can be increased. In the pseudo-crystallization treatment, the resin hard segments are rearranged by heating to form a metastable intermediate phase, and a pseudo-crystallization-like cross-linking point is formed, such as the heat resistance and sag resistance of the network structure. It is thought that the durability is improved.

  As described above, the network structure manufacturing apparatus of the present invention is provided in a nozzle having a discharge hole for extruding a molten thermoplastic resin as a line, a water tank disposed below the nozzle, and a water tank. And a transport device that transports the net-like structure having a linear resin, and a gas discharge device that is provided in the water tank and discharges a gas. With such a configuration, the gas release device provided in the water tank can release gas to cause convection in the water of the water tank, and it is easy to efficiently cool the surface portion and the inside of the network structure. Thus, it is possible to provide a manufacturing apparatus for manufacturing a network structure that is less likely to generate cooling spots in the thickness direction of the network structure and has sufficient durability.

DESCRIPTION OF SYMBOLS 1: Reticulated structure manufacturing apparatus 10: Nozzle 11: Ejection hole 12: Line resin 20: Water tank 30: Conveyance apparatus 31: 1st conveyance apparatus 32: 2nd conveyance apparatus 33: Conveyor belt 34: Drive roller 34a: Upper part Drive roller 34b: Lower drive roller 40: Gas discharge device 41: First gas discharge device 42: Second gas discharge device 43: Release hole 50: Reticulated structure pulling device 60: Reticulated structure P1: First transfer device and first 2 Midpoint with transfer device p1: Vertical plane including midpoint P1

Claims (10)

A nozzle having a discharge hole for extruding the molten thermoplastic resin as a line;
A water tank disposed below the nozzle;
A conveying device that is provided in the water tank and conveys a network structure having the resin of the filament;
A network structure manufacturing apparatus, comprising: a gas discharge device that is provided in the water tank and discharges gas.   The network structure manufacturing apparatus according to claim 1, wherein the gas release device is provided below the transfer device. The gas discharge device has a discharge hole for discharging gas,
The network structure manufacturing apparatus according to claim 1 or 2, wherein a normal direction of the discharge hole is directed to a water surface of the water tank. The transfer device is composed of at least a first transfer device and a second transfer device,
There is the mesh structure between the first transfer device and the second transfer device,
The gas discharge device has a discharge hole for discharging gas,
The network structure manufacturing apparatus according to any one of claims 1 to 3, wherein a normal direction of the discharge hole is directed to a network structure between the transport devices.   The network structure manufacturing apparatus according to any one of claims 1 to 4, wherein the amount of gas released from the gas release device increases as the amount of resin extruded from the nozzle increases.   The network structure manufacturing apparatus according to any one of claims 1 to 5, wherein the amount of gas released by the gas release device increases as the speed of the transfer device increases.   The said conveyance apparatus is a mesh-structure manufacturing apparatus as described in any one of Claims 1-6 which has a mesh-shaped belt and a drive roller. On one side of the water tank, it has a net-like structure pulling device that pulls the net-like structure,
The transfer device is composed of at least a first transfer device and a second transfer device,
The said gas discharge | release apparatus is arrange | positioned at the said network structure traction apparatus side rather than the vertical plane containing the midpoint of a said 1st conveying apparatus and a said 2nd conveying apparatus. The network structure manufacturing apparatus as described. The gas release device comprises at least a first gas release device and a second gas release device,
The transfer device is composed of at least a first transfer device and a second transfer device,
The first gas release device is provided below the vertical direction of the first transfer device,
The network structure manufacturing apparatus according to any one of claims 1 to 8, wherein the second gas release device is provided below the second transfer device in a vertical direction. Extruding the molten thermoplastic resin into a filament,
A step of transporting the network structure having the resin of the filament in a water tank by a transport means;
And a step of releasing a gas into the water in the water tank by a gas releasing device.

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