JP2015117447A - Spinning pack, method for producing spinning pack, and method for modification of spinning pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a retention of polymer in a spinning pack as much as possible in which a polygonal cross-section metallic short fiber filter is used instead of a granular filter medium.SOLUTION: A spinning pack 4 includes: a flow channel forming body 40 having a polymer filling space 49; a volume reduction body 57 accommodated in the polymer filling space 49; a filter 44 having a first filter layer 51 formed by sintering a metallic short fiber having a polygonal cross-section; and a spinneret 41 in which a plurality of nozzles 54 are formed for spinning molten polymer passed through the filter 44, respectively.

Description

  The present invention relates to a spin pack provided with a spinneret for spinning a molten polymer, a method for producing a spin pack, and a method for remodeling a spin pack.

  Conventionally, a melt spinning apparatus for spinning synthetic fiber yarn is known. A typical melt spinning apparatus includes a spinning pack having a spinneret. A melt polymer is supplied to the spin pack, and the melt polymer is spun from a plurality of nozzles of the spinneret to form a plurality of filaments.

  A typical spin pack includes a filter medium for filtering the molten polymer. Patent Documents 1 and 2 disclose a spinning pack having a particulate filter medium such as sand. These spin packs have, in order from the top, polymer introduction holes, granular filter media, filters, spinnerets, and the like. A space connected to the polymer introduction hole is provided inside the spinning pack, and the particulate filter medium is filled in this space. The molten polymer introduced into the space from the polymer introduction hole passes through the particulate filter medium and the filter, and is then spun from a plurality of nozzles of the spinneret.

JP 2002-266152 A Japanese Examined Patent Publication No. 62-1001

  The particulate filter material used in Patent Documents 1 and 2 is another important in that it melts the molten polymer and collects foreign substances contained in it, and further subdivides the gelled portion of the molten polymer. Have a role. Sand particles, metal sand, and the like constituting the particulate filter medium have sharp corners on their outer surfaces. When the molten polymer passes through the granular filter medium, the gelled portion of the molten polymer is divided by the acute angle portion of the granular filter medium. Since the gel-like part is a solid foreign substance that has a high viscosity and has lost its fluidity, if the gel-like part is not sufficiently trapped or subdivided, it will become a large gel in the molten polymer spun from the nozzle. The part will remain, which will be a major factor in yarn quality degradation and filament (single yarn) breakage.

  However, spinning packs using granular filter media have the following various problems. First, the particulate filter medium is locally opened or compressed locally by the pressure of the supplied molten polymer. Thereby, the porosity of a filter medium changes locally and filtration performance changes. As the porosity increases, the filtration performance decreases. Moreover, since the filtration pressure increases when the porosity decreases, it is necessary to replace the pack at an early stage. For this reason, generally, a spinning pack using a granular filter medium has a short pack life. Further, if the amount of openings or the amount of compression is biased in the filter medium, the porosity will vary, and the polymer will not flow uniformly in the granular filter medium. As a result, the amount of polymer spun from each of the plurality of nozzles becomes non-uniform, and physical properties such as thickness (fineness) differ between filaments. Furthermore, since it takes time to reuse the particulate filter medium, in many cases, the filter medium is discarded every time the spinning pack is replaced. Therefore, the amount of waste increases in combination with the short pack life.

  Therefore, the present inventor has developed a spinning pack that does not use a particulate filter medium. Specifically, a filter formed by sintering short metal fibers having a polygonal cross section (hereinafter referred to as “polygonal cross section metal short fiber filter”) is used instead of the granular filter medium. Polygonal cross-section metal short fiber filters are disclosed in, for example, Japanese Patent Application Laid-Open Nos. 5-253418 and 2005-256197. When the molten polymer passes through the polygonal cross-section metal short fiber filter, the gel-like portion in the polymer is divided by the acute angle portion of the metal short fiber having a polygonal cross section. That is, the polygonal cross-section metal short fiber filter has a function of subdividing the gel-like portion in the molten polymer, like the granular filter medium.

  By the way, as for the above-described spinning pack using a polygonal cross-section metal short fiber filter instead of the granular filter medium, it is possible to newly adopt a pack structure completely different from the spinning pack using the conventional granular filter medium. . However, if the spin pack can be used as a new spin pack by slightly modifying the inside of the spin pack that has already been used, costs can be saved, which is preferable for users of the melt spinning apparatus. If the size of the pack is greatly different between the conventional spinning pack and the new spinning pack, the position of each device of the melt spinning device must be adjusted accordingly. For example, when the vertical dimension of the spin pack changes, the distance between the spinning position of the polymer from the spinneret and the lower surface of the apparatus to which the spin pack is attached (the heating box in this embodiment corresponds to this) is Will change. Therefore, it is necessary to adjust the position of the spinneret by changing the spin pack mounting member of the apparatus. In this regard, if the main components such as the members with the polymer flow path are shared between the conventional spin pack and the new spin pack, the size of the new spin pack is made equal to that of the conventional spin pack, and a new spin pack is created. Even if a pack is used, the spinning position can be kept unchanged. In addition, it is possible to reduce the manufacturing cost of a new spin pack by sharing the main parts between the conventional spin pack and the new spin pack.

  In view of the above points, the inventor of the present application is studying to construct a new spin pack using the same parts as the conventional spin pack using the particulate filter medium. Specifically, in a part in which a polymer flow path is formed (flow path forming body), a polymer filling space formed inside is not filled with a granular filter medium, and instead of this granular filter medium, a polygonal cross-section metal is used. Install a short fiber filter. However, in this case, it has been found that the following problems occur.

  In the conventional spin pack, since the particulate filter medium is accommodated in the polymer filling space, the space in the polymer filling space where the molten polymer is actually filled is reduced accordingly. However, since a new spin pack does not use a particulate filter medium, a large amount of molten polymer is filled in the polymer filling space, and the residence time of the polymer becomes long. As a result, the polymer undergoes alteration due to thermal degradation, causing thread breakage and thread quality unevenness.

  An object of the present invention is to suppress the retention of a polymer in the pack as much as possible in a spin pack using a polygonal cross-section metal short fiber filter instead of a granular filter medium.

Means for Solving the Problems and Effects of the Invention

  A spinning pack according to a first aspect of the present invention includes a flow path forming body having an introduction portion into which a molten polymer is introduced, a polymer filling space connected to the introduction portion and filled with the molten polymer, and the flow passage formation body. A volume reduction body accommodated in at least a lower space of the polymer-filled space, and a metal short fiber disposed at a position below the volume reduction body in the flow path forming body and having a polygonal cross section is sintered. A filter having a first filter layer, and a spinneret formed on the lower side of the flow path forming body and formed with a plurality of nozzles for spinning the molten polymer that has passed through the filter. It is characterized by that.

  In the present invention, a filter having a first filter layer formed by sintering short metal fibers having a polygonal cross section is used instead of filling the polymer filling space of the flow path forming body with the particulate filter medium. The first filter layer of the filter ensures that the gel-like portion in the molten polymer is subdivided. In addition, if the lower part of the polymer filling space of the flow path forming body is not filled with the particulate filter medium, the volume of the actual filling space in the polymer filling space where the molten polymer is actually filled increases. The residence time of becomes longer. In this regard, in the present invention, the volume reducing body is accommodated in the lower space of the polymer filling space, and the volume of the actual filling space of the polymer filling space is reduced by the volume of the volume reducing body. Therefore, the residence time of the molten polymer in the polymer filling space is shortened, and the deterioration of the molten polymer due to thermal deterioration is suppressed.

  The spin pack of the second invention is characterized in that, in the first invention, the volume occupied by the volume reduction body in the polymer filling space is 60 to 90% of the total volume of the polymer filling space. Is. In the spin pack of the third invention, in the second invention, the volume occupied by the volume-reducing body in the polymer filling space is 75 to 90% of the total volume of the polymer filling space. It is what.

  If the volume occupied in the polymer-filled space of the volume reducing body is small, the effect of shortening the residence time is reduced. On the other hand, if the volume occupied by the volume-reducing body is too large, the space in the polymer filling space where the polymer is actually filled becomes too small and the flow resistance increases, and conversely, the polymer tends to stay. Therefore, the occupied volume in the polymer filling space of the volume reducing body is preferably in the range of 60 to 90%, and more preferably in the range of 75 to 90%.

  A spinning pack according to a fourth invention is characterized in that, in any one of the first to third inventions, a gap between a lower end of the volume reducing body and an upper surface of the filter is 1 to 3 mm. Is.

  If the gap between the lower end of the volume reducing body and the upper surface of the filter is too large, the residence time of the molten polymer before passing through the filter becomes long. On the other hand, if the gap is too small, the flow resistance when the polymer flows through the gap increases, and conversely, the polymer tends to stay. Therefore, the gap between the lower end of the volume reducing body and the upper surface of the filter is preferably within a range of 1 to 3 mm.

  A spinning pack according to a fifth aspect of the present invention is the spinning pack according to any one of the first to fourth aspects, wherein the filter is disposed below the first filter layer, and short metal fibers having a circular cross section are sintered. The second filter layer is further characterized in that the filtration particle size of the second filter layer is smaller than the filtration particle size of the first filter layer.

  By the first filter layer, the gel-like portion of the molten polymer is subdivided, and at the same time, a relatively large foreign matter contained in the molten polymer is collected. On the other hand, the small foreign matter which was not collected in the 1st filter layer is removed by the 2nd filter layer with small filtration particle size.

A spinning pack manufacturing method according to a sixth aspect of the present invention includes an introduction part into which a molten polymer is introduced, and a polymer filling space connected to the introduction part and filled with the molten polymer, and the polymer filling space is granular. A method for producing a second spin pack that does not use the particulate filter medium by using a flow path forming body that constitutes the first spin pack by containing the filter medium,
A volume reducing body for reducing the volume of the actual filling space in which the molten polymer is actually filled in the space in which the granular filter medium is accommodated in the first spinning pack in the polymer filling space of the flow path forming body. A filter having a first filter layer that is accommodated and sintered with a short metal fiber having a polygonal cross section is attached to a lower position of the volume reducing body in the flow path forming body. .

  According to the present invention, since a second spinning pack that does not use the granular filter medium is manufactured using the same flow path forming body as the first spinning pack that uses the granular filter medium, the flow path is formed by using two types of spin packs. The body is shared. Also, at this time, in the second spinning pack that does not use the particulate filter medium, the volume filling material is accommodated in the polymer-filled space, and in the first spinning pack, the particulate filter medium is accommodated in the first spinning pack. The space can be reduced to prevent the molten polymer from staying in the polymer-filled space.

According to a seventh aspect of the present invention, there is provided a spinning pack remodeling method comprising: a flow path forming body having an introduction portion into which a molten polymer is introduced; and a polymer filling space connected to the introduction portion and filled with the molten polymer; A particulate filter medium accommodated in the polymer-filled space of the passage forming body, a pre-remodeling filter disposed on the lower side of the granular filter medium in the flow path forming body, and a lower side of the flow path forming body. A first spinning pack comprising a spinneret having a plurality of nozzles for spinning each of the molten polymers that have passed through the pre-remodeling filter, and a second spinning pack that does not use a granular filter medium. Because
The particulate filter medium in the polymer filling space of the flow path forming body is removed, the pre-remodeling filter is removed from the flow path forming body, and the granular filter medium in the polymer filled space is accommodated in the molten state. A flow path forming body comprising a first filter layer containing a volume reducing body for reducing the volume of an actual filling space where the polymer is actually filled and sintered with short metal fibers having a polygonal cross section. It attaches to the lower position of the said volume reduction body, It is characterized by the above-mentioned.

  In the present invention, the first spin pack using the granular filter medium can be easily modified to the second spin pack not using the granular filter medium. In addition, when the second spinning pack is remodeled, the volume filling material is accommodated in the space in which the particulate filter medium in the polymer filling space is accommodated, thereby reducing the actual filling space of the molten polymer, and the polymer filling space. It is possible to suppress the retention of the molten polymer inside.

1 is a schematic configuration diagram of a melt spinning apparatus and a spinning take-up machine according to the present embodiment. It is sectional drawing of the pack mounting part of a spinning pack and a heating box. It is sectional drawing of a filter. (A) is a rough expanded sectional view of the A section of FIG. 3, (b) is a schematic expanded sectional view of the B section of FIG. It is sectional drawing of the spinning pack using a granular filter medium, and a pack mounting part. It is sectional drawing of the spinning pack which concerns on another modified form, and a pack mounting part.

  Next, an embodiment of the present invention will be described. FIG. 1 is a schematic configuration diagram of a melt spinning apparatus 1 and a spinning take-up machine 2 that winds a yarn Y spun from the melt spinning apparatus 1 according to the present embodiment. The vertical direction in FIG. 1 is defined as the vertical direction of the melt spinning apparatus 1 and the spinning take-up machine 2. First, schematic configurations of the melt spinning apparatus 1 and the spinning take-up machine 2 will be described.

  The melt spinning apparatus 1 includes a heating box 3 and a plurality of spinning packs 4 that are detachably attached to the heating box 3. The plurality of spin packs 4 are arranged side by side in the direction perpendicular to the paper surface of FIG. From each spinning pack 4, a yarn Y composed of a plurality of filaments f is spun downward. The configuration of the melt spinning apparatus 1 including the spinning pack 4 will be described in detail later.

  The spinning take-up machine 2 includes an oil guide 10, a guide roller 11, five godet rollers 12 to 16, a guide roller 17, and a winding device 18. The plurality of yarns Y spun downward from the plurality of spinning packs 4 of the melt spinning apparatus 1 are fed with the oil agent by the oil agent guide 10 and then sent to the five godet rollers 12 to 16 by the guide roller 11.

  Each of the five godet rollers 12 to 16 is a heating roller having a heater therein, and is housed in a heat insulation box 19. The lower three godet rollers 12 to 14 are heating rollers for preheating the plurality of yarns Y before drawing. On the other hand, the upper two godet rollers 15 and 16 are heating rollers for heat-setting a plurality of stretched yarns Y. Further, the yarn feeding speeds of the two godet rollers 15 and 16 located on the downstream side in the yarn feeding direction are faster than the three godet rollers 12 to 14 located on the upstream side in the yarn feeding direction.

  The plurality of yarns Y introduced into the heat insulation box 19 are first preheated to a temperature that can be stretched while being fed by the lower three godet rollers 12 to 14, and then the plurality of preheated yarns Y are The two godet rollers 14 and 15 are stretched by a difference in yarn feed speed. Further, the plurality of yarns Y are heated to a higher temperature while being fed by the upper two godet rollers 15 and 16, and the stretched state is heat set. The plurality of yarns Y drawn by the five godet rollers 12 to 16 in the heat insulation box 19 are sent to the winding device 18 by the guide roller 17.

  The winding device 18 includes a bobbin holder 20 and a contact roller 21. The bobbin holder 20 has a long shape extending in the direction perpendicular to the plane of FIG. 1 and is driven to rotate by a motor (not shown). A plurality of bobbins 22 are attached to the bobbin holder 20 along the axial direction. The winding device 18 rotates the bobbin holder 20 to simultaneously wind the plurality of yarns Y sent by the guide roller 17 around the plurality of bobbins 22 to form a plurality of winding packages 23. The contact roller 21 contacts the surface of the plurality of winding packages 23 and applies a predetermined contact pressure to adjust the shape of the winding package 23.

  Next, the melt spinning apparatus 1 will be described in detail. FIG. 2 is a cross-sectional view of the spinning pack 4 and the pack mounting portion 31 of the heating box 3. In FIG. 2, only the pack mounting portion 31 of the heating box 3 is indicated by a solid line, and other portions are indicated by a two-dot chain line.

  First, the heating box 3 to which the spinning pack 4 is mounted will be described. The heating box 3 distributes and supplies the molten polymer to the plurality of spinning packs 4. In this embodiment, a molten polymer such as polyester having a viscosity of 300 Pa · s or less is used to produce a yarn for clothing. The inside of the heating box 3 is filled with a heat medium vapor supplied from a boiler (not shown) and is kept at a high temperature (for example, about 300 ° C.). Thereby, the molten polymer which passes the inside of the heating box 3 is maintained within a certain appropriate temperature range. The heating box 3 has a plurality of storage recesses 30 on its lower surface. Each storage recess 30 has a cylindrical hole shape, and a pack mounting portion 31 is attached to the ceiling surface of each storage recess 30. The spinning pack 4 is also maintained at a high temperature by being inserted into the storage recess 30 of the high-temperature heating box 3.

  The pack mounting portion 31 is a member having a substantially T-shaped cross section including a disk-shaped fixing portion 32 and a shaft portion 33 extending directly from a substantially central portion of the lower surface of the fixing portion 32. In the pack mounting portion 31, a polymer flow path 34 penetrating vertically through the pack mounting portion 31 is formed from the fixed portion 32 to the lower end of the shaft portion 33. The fixing part 32 is fixed to the ceiling surface of the housing recess 30 of the heating box 3 by a bolt (not shown). At this time, the upper end of the polymer flow path 34 is connected to a polymer flow path (not shown) in the heating box 3. Further, a male screw portion 33 a is formed on the outer surface of the shaft portion 33.

  Next, the spinning pack 4 will be described. The spinning pack 4 is inserted into the storage recess 30 of the heating box 3 and is detachably mounted on the pack mounting portion 31. The spin pack 4 includes a flow path forming body 40, a spinneret 41, a case member 42, a lock ring 43, and the like. The flow path forming body 40 has a substantially cylindrical shape. The case member 42 has a cylindrical shape, and the flow path forming body 40 and the spinneret 41 are accommodated in the case member 42. A plurality of nozzles 54 provided on the lower surface of the spinneret 41 are exposed at the lower end opening 42 a of the case member 42. The lock ring 43 is attached to the upper portion of the case member 42 and prevents the flow path forming body 40 from dropping (disconnecting) from the case member 42.

(Channel formation body)
The flow path forming body 40 will be described. The flow path forming body 40 is a structure in which a polymer flow path in which a molten polymer flows, such as a polymer filling space 49 described later, is formed inside. As shown in FIG. 2, the flow path forming body 40 includes a first flow path member 40a, a second flow path member 40b, and a third flow path member 40c arranged in order from the top. The three flow path members 40a to 40c are each formed of metal.

  A bottomed cylindrical portion 46 is formed on the upper portion of the first flow path member 40a. A female screw portion 46 a is formed on the inner peripheral surface of the cylindrical portion 46. Further, an introduction portion 47 for introducing a molten polymer into the spinning pack 4 is formed at the bottom of the cylindrical portion 46. When the spinning pack 4 is rotated and inserted into the housing recess 30 of the heating box 3, the male threaded portion 33a of the shaft portion 33 of the pack mounting portion 31 and the female threaded portion 46a of the cylindrical portion 46 of the first flow path member 40a are screwed. By combining, the spinning pack 4 is mounted on the pack mounting portion 31. The pack mounting portion 31 is provided with a regulating member 35 for preventing the spinning pack 4 from rotating more than a predetermined angle with respect to the pack mounting portion 31. When the spinning pack 4 is mounted on the pack mounting portion 31, the lower end surface of the shaft portion 33 of the pack mounting portion 31 is pressed against the bottom of the cylindrical portion 46 of the first flow path member 40a, and the pack mounting portion 31 side is pressed. The polymer flow path 34 and the introduction part 47 of the first flow path member 40a are connected. A packing 48 is provided between the shaft portion 33 of the pack mounting portion 31 and the cylindrical portion 46 of the first flow path member 43 to seal the connecting portion between the polymer flow path 34 and the introduction portion 47. ing.

  A concave portion 55 opened downward is formed in the lower portion of the first flow path member 40a, and a concave portion 56 opened upward is formed in the upper portion of the second flow path member 40b below. A polymer filling space 49 is formed by the recess 55 of the first flow path member 40a and the recess 56 of the second flow path member 40b. The polymer filling space 49 is connected to the introduction part 47, and the polymer filling space 49 is filled with the molten polymer introduced into the spinning pack 4 from the introduction part 47.

  The polymer-filled space 49 does not contain conventionally used particulate filter media, and instead contains a volume reduction body 57. The molten polymer that has flowed into the polymer filling space 49 from the introduction portion 47 flows down to the lower side of the volume reducing body 57 through a gap formed between the inner surface of the polymer filling space 49 and the outer surface of the volume reducing body 57. The volume reducing body 57 will be described in detail later.

  A filter 44 is disposed at a position below the volume reducing body 57 in the polymer filling space 49. The filter 44 includes a first filter layer 51, a second filter layer 52, and a third filter layer 53, which are stacked in order from the top. The filter 44 collects foreign substances contained in the molten polymer. Further, as mentioned above, the spin pack 4 of the present embodiment does not use a granular filter medium, but the filter 44 is a fragmentation of a gel-like portion in a molten polymer, which is conventionally performed by a granular filter medium. It also has a function to do. Details of the filter 44 will be described later. A plurality of through holes 58 are formed in the lower portion of the filter 44 of the second flow path member 40b. The molten polymer that has passed through the filter 44 is rectified by the plurality of through holes 58.

  The third flow path member 40c is formed with a divergent distribution space 59 that expands downward. A filter 60 is disposed below the distribution space 59. The molten polymer flowing from the plurality of through holes of the second flow path member 40b spreads in the horizontal direction in the distribution space and then passes through the filter 60.

(Spinneret)
The spinneret 41 is disposed in contact with the lower surface of the filter 60. The spinneret 41 has a plurality of nozzles 54. The molten polymer that has passed through the two filters 44 and 60 is spun from the plurality of nozzles 54 to form a plurality of filaments f.

(Volume reduction)
Next, the volume reducing body 57 will be described in detail. The volume reducing body 57 is a substantially cylindrical member formed of a metal material. However, the lower end portion of the volume reducing body 57 has a conical shape protruding downward at the center portion thereof. The volume reduction body 57 is intended to reduce the volume of the actual filling space in which the polymer filling space 49 having a relatively large inner volume is actually filled with the molten polymer, thereby suppressing the retention of the molten polymer in the polymer filling space 49. Is provided.

  As shown in FIG. 2, the cross-sectional area of the upper space of the polymer filling space 49 is slightly larger than the lower space, and an annular step 49a exists between the upper space and the lower space. On the other hand, the volume reduction body 57 has a plurality of leg portions 57a provided at intervals in the circumferential direction on the outer peripheral portion thereof. The volume-reducing body 57 is accommodated in a state in which a narrow gap is left between the inner surface from the upper end portion to the lower end portion of the polymer filling space 49 by placing a plurality of leg portions 57a on the annular stepped portion 49a. Has been.

(filter)
Next, the configuration of the filter 44 will be described in detail. FIG. 3 is a cross-sectional view of the filter 44. As shown in FIG. 3, FIG. 4A is a schematic enlarged cross-sectional view of the first filter layer 51 at a portion A in FIG. 3. FIG. 4B is a schematic enlarged cross-sectional view of the second filter layer 52 at a portion B in FIG.

  The first filter layer 51 is a layer formed by sintering a large number of first metal short fibers 50a. More specifically, as shown in FIG. 4A, the first short metal fibers 50a constituting the first filter layer 51 have a polygonal cross section (for example, a triangular cross section) with an acute corner. As a metal material used as the raw material of the 1st filter layer 51, materials with high corrosion resistance, such as stainless steel, are preferable. The first short metal fibers 50a having the polygonal cross section can be generally manufactured by a chatter vibration cutting method. In the chatter vibration cutting method, while rotating a metal material as a raw material, a self-excited vibration (chatter vibration) is intentionally generated in the cutting tool to process the metal material, thereby producing ultrafine short fibers. The first metal short fiber 50a manufactured by this method has an acute polygonal cross section due to the chatter vibration. The first metal short fiber 50a has a fiber length of 1.0 to 3.0 mm, a diameter (in terms of a circular cross section) of 30 to 100 μm, and an aspect ratio of 10 to 100.

  The porosity of the first filter layer 51 is 60 to 80%, which is almost the same as the porosity of metal powder often used in conventional spinning packs. Moreover, since the fiber diameter of the 1st metal short fiber 50a is comparatively large as mentioned above, it is difficult to make the filtration particle size of the 1st filter layer 51 small, for example, is 20 micrometers or more. The filtration particle size (also referred to as filtration accuracy) is an index indicating how large foreign matter can be removed by the filter, and the filtration particle size of 20 μm means that 95% or more of foreign matters having a size of 20 μm or more are removed. It shows that.

  By the way, a part of the molten polymer supplied to the spinning pack 4 may be gelled. In this respect, since the first filter layer 51 is a layer formed by sintering the short metal fibers 50 having a polygonal cross section, the gel-like portion is contained in the molten polymer supplied from the heating box 3 to the spinning pack 4. Even if there is, the gelled portion is divided and subdivided so as to be chopped by the sharp corners of a large number of short metal fibers 50 when passing through the first filter layer 51. The granular filter medium used in the conventional spinning pack also has a function of subdividing the gel-like portion in the molten polymer, but omitting the granular filter medium by providing the first filter layer 51 instead of the conventional granular filter medium. It becomes possible to do.

  The second filter layer 52 is also a layer formed by sintering a large number of second metal short fibers 50b. In addition, the 2nd metal short fiber 50b which comprises the 2nd filter layer 52 is obtained by extending a wire-like metal. Therefore, as shown in FIG. 4B, the second short metal fibers 50b have a substantially circular cross-sectional shape in a cross section orthogonal to the fiber length. Here, the “circular cross section” includes not only a perfect circular shape but also a cross sectional shape close to an ellipse. The second filter layer 52 is also preferably formed of a material having high corrosion resistance such as stainless steel, like the first filter layer 51. The fiber length of the second short metal fibers 50b is 20 to 30 mm, and the fiber diameter is 10 to 30 μm.

  The porosity of the second filter layer 52 is the same as that of the first filter layer 51, and is, for example, 60 to 80%. The second filter layer 52 is a layer having a smaller filtration particle size than the first filter layer 51. Since the second metal short fibers 50b constituting the second filter layer 52 have a smaller fiber diameter than the first metal short fibers 50a, the filtration particle size of the second filter layer 52 can be reduced. Although the filtration particle size of the 2nd filter layer 52 is based also on the filtration particle size of the 1st filter layer 51 used together with this, it is 10-40 micrometers, for example. The second filter layer 52 removes small foreign matters that could not be collected by the first filter layer 51 having a relatively large filtration particle size.

  The third filter layer 53 is a wire mesh filter. The type of wire mesh is not particularly limited, and a general plain weave wire mesh or other wire meshes such as twill weave, plain tatami mat, twill tatami weave, and the like can also be used. The main purpose of providing the third filter layer 53 formed of a wire mesh is to reinforce the first filter layer 51 and the second filter layer 52.

  If the mesh of the metal mesh constituting the third filter layer 53 is too fine, the rigidity of the third filter layer 53 is low and a sufficient reinforcing effect cannot be obtained. Therefore, the number of meshes per inch (hereinafter also simply referred to as the number of meshes) indicating the fineness of the third filter layer 53 is 30 to 100 meshes. Since the third filter layer 53 is laminated on the first filter layer 51 and the second filter layer 52, the rigidity of the filter 44 is increased, and deformation of the filter 44 due to the pressure of the molten polymer is suppressed.

  The three filter layers 51 to 53 may be individually assembled to the flow path forming body 40, or may be integrated in a state where the three filter layers 51 to 53 are laminated in advance. Good. For example, three filter layers 51 to 53 may be joined by spot welding. Alternatively, the three filter layers 51 to 53 may be fixed to each other by ring-shaped fixing members (rims) attached to the outer peripheral portions of the three filter layers 51 to 53. In this case, since the gap between the outer peripheral portions of the three filter layers 51 to 53 is closed by the ring-shaped fixing member, the molten polymer is prevented from leaking from the gap. As described above, when the three filter layers 51 to 53 are integrated, it is easy to attach the filter 44 when the spin pack 4 is assembled or to remove the filter 44 when the spin pack 4 is disassembled. become.

  By the way, as described above, in the spinning pack 4 of the present embodiment, the volume reducing body 57 is accommodated in the polymer filling space 49. The reason will be supplementarily described below. First, the spin pack 4 of the present embodiment (corresponding to the second spin pack in the present invention) is a spin pack 100 in which a granular filter medium is used as shown in FIG. 5 (in the first spin pack in the present invention). Equivalent) and some main parts (the flow path forming body 40, the spinneret 41, the case member 42, the lock ring 43, etc.).

  In the spinning pack 100 shown in FIG. 5, the distribution member 101 is accommodated in the upper space of the polymer filling space 49 formed in the flow path forming body 40, and the granular filter medium 102 such as metal sand or sand is accommodated in the lower space. Contained. The main function of the particulate filter medium 102 is to subdivide the gel-like portion in the molten polymer. Further, a filter 103 is disposed below the granular filter medium 102. The main function of the filter 103 is to collect foreign matter, and a structure in which a sintered metal nonwoven fabric filter layer 112 (same as the second filter layer 52 in the spinning pack 4) is sandwiched between two wire mesh filter layers 111. It is. On the other hand, in the spinning pack 4 of this embodiment shown in FIG. 2, the particulate filter medium 102 is not accommodated in the polymer filling space 49. Furthermore, a filter 44 having a first filter layer 51 which is a polygonal cross-section metal short fiber filter is provided as a substitute for the granular filter medium 102.

  By the way, in the spinning pack 4 of this embodiment, since the particulate filter medium 102 is not filled in the space below the polymer filling space 49 of the flow path forming body 40, the molten polymer in the polymer filling space 49 is actually left as it is. The volume of the actual filling space filled with is increased, and the residence time of the polymer is increased. Therefore, in this spinning pack 4, a volume reducing body 57 is accommodated in a lower space of the polymer filling space 49 in which the particulate filter medium 102 is accommodated in the spinning pack 100 of FIG. The volume of the actual filling space of the polymer filling space 49 is reduced by the volume of the volume reducing body 57. Therefore, the residence time of the molten polymer in the polymer filling space 49 is shortened, and the deterioration of the molten polymer due to thermal deterioration is suppressed.

  If the volume occupied by the volume reduction body 57 in the polymer filling space 49 is small, the effect of shortening the residence time of the molten polymer in the polymer filling space 49 becomes low. On the other hand, if the volume occupied by the volume reducing body 57 is too large, the space in the polymer filling space 49 where the polymer is actually filled becomes too small and the flow resistance increases, and conversely, the polymer tends to stay. Therefore, the occupied volume in the polymer filling space 49 of the volume reducing body 57 is preferably in the range of 60 to 90%. Furthermore, in order to shorten the residence time of the molten polymer, the occupied volume in the polymer filling space 49 of the volume reducing body 57 is more preferably in the range of 75 to 90%.

  Similarly, if the gap between the lower end of the volume reducing body 57 and the upper surface of the filter 44 is too large, the residence time of the molten polymer before passing through the filter 44 will become long. On the other hand, if the gap is too small, the flow resistance when the polymer flows through the gap increases, and conversely, the polymer tends to stay. Therefore, the gap G between the lower end of the volume reducing body 57 and the upper surface of the filter 44 is preferably within a range of 1 to 3 mm.

  As can be understood from the above description, the spin pack 4 of the present embodiment has the same components (the flow path forming body 40, the spinneret 41, etc.) as those used in the spin pack 100 using the granular filter medium 102. And can be produced. That is, first, the volume reducing body 57 is arranged from the upper space of the polymer filling space 49 of the flow path forming body 40 to the lower space in which the particulate filter medium 102 is accommodated when used as the spin pack 100. Further, the filter 44 including the first filter layer 51 formed by sintering the first metal short fibers 50 a having a polygonal cross section is attached to a position below the volume reducing body 57 in the flow path forming body 40. Then, the flow path forming body 40 to which the volume reducing body 57 and the filter 44 are attached and the spinneret 41 are accommodated in the case member 42 and then the lock ring 43 is attached.

  Thus, in order to manufacture the spin pack 4 that does not use the granular filter medium 102 by using the same flow path forming body 40 as the spin pack 100 that uses the granular filter medium 102, the flow path is formed by using two types of spin packs 4 and 100. The body 40 can be shared. Further, when the flow path forming body 40 is shared, the spin pack 100 using the granular filter medium 102 does not use the granular filter medium 102 by storing the volume reducing body 57 in the space in which the granular filter medium 102 is stored. The actual filling space of the molten polymer in the spinning pack 4 can be reduced, and the retention of the molten polymer in the polymer filling space 49 can be suppressed.

  Alternatively, the spin pack 100 using the granular filter medium 102 of FIG. 5 can be modified to the spin pack 4 of the present embodiment that does not use the granular filter medium 102 of FIG. In this case, first, the lock ring 43 is removed, and the flow path forming body 40 is removed from the case member 42. Next, the distribution member 101 and the particulate filter medium 102 in the polymer filling space 49 of the flow path forming body 40 are removed. Further, the filter 103 (corresponding to the pre-remodeling filter of the present invention) is removed from the flow path forming body 40. Then, the volume reducing body 57 is disposed in the polymer filling space 49 from the upper space in which the distribution member 101 is accommodated to the lower space in which the particulate filter medium 102 is accommodated. Further, the filter 44 having the first filter layer 51 formed by sintering the first metal short fibers 50 a having a polygonal cross section is attached to the flow path forming body 40 at a position below the volume reducing body 57. Then, after the flow path forming body 40 to which the volume reducing body 57 and the filter 44 are attached is accommodated in the case member 42 again, the lock ring 43 is attached.

  In this way, the spin pack 100 using the granular filter medium 102 can be easily modified to the spin pack 4 not using the granular filter medium 102. Here, at the time of remodeling to the spinning pack 4, by storing the volume reducing body 57 in the lower space of the polymer filling space 49 in which the particulate filter medium 102 was accommodated, the actual filling space of the molten polymer is reduced, The retention of the molten polymer in the polymer filling space 49 can be suppressed.

  Next, modified embodiments in which various modifications are made to the embodiment will be described. However, components having the same configuration as in the above embodiment are given the same reference numerals and description thereof is omitted as appropriate.

1] The volume reducing body 57 may be any one that can reduce the actual filling space filled with the molten polymer in the polymer filling space 49, and the shape thereof is not limited to that of the above-described embodiment. For example, as shown in FIG. 6, the volume reducing body 57 may have a shape whose lower end surface is parallel to the filter 44. Moreover, although the volume reduction body 57 of the said embodiment was a solid member, the volume reduction body 57 may be a hollow member which has the sealed cavity part in the inside.

  Further, in the above embodiment, since the distribution member 101 is disposed on the granular filter medium 102 in the spinning pack 100 of FIG. 5, the volume reducing body 57 is the upper part of the polymer filling space 49 in the spinning pack 4 of FIG. 2. It is arranged from the space to the lower space. That is, the upper half of the volume reducing body 57 of the spin pack 4 has a function equivalent to that of the distribution member 101 of the spin pack 100. On the other hand, in the spinning pack 100 using the particulate filter medium 102, the distribution member 101 may be unnecessary depending on conditions such as the viscosity of the molten polymer. In this case, the volume reducing body 57 may be disposed only in the lower space of the polymer filling space 49 in which the particulate filter medium 102 is accommodated.

2] The spin pack 4 of the above embodiment spins one yarn Y composed of a plurality of filaments f, but the present invention is also applied to a spin pack that spins two or more yarns Y. Can be applied. Moreover, it is applicable also to what has the two or more introduction parts 47 into which a molten polymer is introduce | transduced. In these forms, a plurality of polymer filling spaces 49 may be provided according to the number of yarns Y spun from the spinneret 41 or the number of introduction portions 47. In that case, the volume reducing body 57 is arranged in each of the plurality of polymer filling spaces 49.

3] In the above embodiment, the filter 44 has a configuration in which three filter layers 51, 52, and 53 are laminated in order from the top. However, the filter 44 is at least a polygonal cross-section metal short fiber sintered filter. What is necessary is just to provide the certain 1st filter layer 51, and it is not restricted to the thing of the structure of the said embodiment. For example, a third filter layer 53 made of a wire mesh may be stacked on the upper side of the first filter layer 51. Alternatively, on the contrary, the third filter layer 53 may be omitted, and the filter 44 may be configured by only two layers of the first filter layer 51 and the second filter layer 52. Further, the second filter layer 52 having a small filtration particle size may be formed of a fine wire mesh (for example, about 400 mesh).

4 Spin pack (second spin pack)
40 Channel Forming Body 41 Spinneret 44 Filter 47 Introduction Portion 49 Polymer Filling Space 51 First Filter Layer 52 Second Filter Layer 57 Volume Reduction Body 100 Spin Pack (First Spin Pack)
102 Granular filter medium 103 Filter (filter before modification)

Claims (7)

A flow path forming body having an introduction part into which a molten polymer is introduced, and a polymer filling space connected to the introduction part and filled with the molten polymer;
A volume reducing body accommodated in at least a lower space of the polymer filling space of the flow path forming body;
A filter having a first filter layer that is disposed at a position below the volume-reducing body in the flow path forming body and in which short metal fibers having a polygonal cross section are sintered;
A spinneret formed on the lower side of the flow path forming body and formed with a plurality of nozzles for spinning the molten polymer that has passed through the filter;
A spinning pack characterized by comprising:   The spin pack according to claim 1, wherein the volume occupied by the volume reduction body in the polymer filling space is 60 to 90% of the total volume of the polymer filling space.   The spin pack according to claim 2, wherein the volume occupied by the volume reduction body in the polymer filling space is 75 to 90% of the total volume of the polymer filling space.   The spin pack according to any one of claims 1 to 3, wherein a gap between a lower end of the volume reduction body and an upper surface of the filter is 1 to 3 mm. The filter further includes a second filter layer disposed under the first filter layer and formed by sintering short metal fibers having a circular cross section.
The spinning pack according to any one of claims 1 to 4, wherein a filtration particle size of the second filter layer is smaller than a filtration particle size of the first filter layer. A first spinning pack having an introduction part into which a molten polymer is introduced, a polymer filling space connected to the introduction part and filled with the molten polymer, and a particulate filter medium being accommodated in the polymer filling space A method for producing a second spin pack that does not use the particulate filter medium, using a flow path forming body comprising:
A volume reducing body for reducing the volume of the actual filling space in which the molten polymer is actually filled in the space in which the granular filter medium is accommodated in the first spinning pack in the polymer filling space of the flow path forming body. Contain,
A method for manufacturing a spin pack, comprising: attaching a filter having a first filter layer formed by sintering metal short fibers having a polygonal cross section to a position below the volume reducing body in the flow path forming body. A flow passage forming body having an introduction portion into which a molten polymer is introduced, a polymer filling space connected to the introduction portion and filled with the molten polymer, and accommodated in the polymer filling space of the flow passage formation body And the pre-remodeling filter disposed on the lower side of the granular filter medium in the flow path forming body, and the molten polymer disposed on the lower side of the flow path forming body and passing through the pre-remodeling filter. A method of remodeling a first spinning pack comprising a spinneret having a plurality of nozzles each spinning into a second spinning pack that does not use granular filter media,
While removing the particulate filter medium in the polymer-filled space of the flow path forming body, removing the pre-modification filter from the flow path forming body,
A volume-reducing body for reducing the volume of the actual filling space in which the molten polymer is actually filled in the space in which the particulate filter medium in the polymer-filling space is accommodated;
A method for remodeling a spinning pack, comprising: attaching a filter having a first filter layer formed by sintering metal short fibers having a polygonal cross section to a position below the volume reducing body of the flow path forming body. .

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