Extrusion molding device

Abstract

To provide an extrusion molding device advantageous in view of reducing a size variation of moldings.SOLUTION: An extrusion molding device 1a includes: a die 10; a gear pump 20; a motor 30; and a power transmission mechanism 40. The die 10 is a component for forming a molding material. The gear pump 20 includes a drive gear 21. The gear pump 20 supplies the molding material to the die 10 by a rotation of the drive gear 21. The power transmission mechanism 40 transmits a power of the motor 30 to the drive gear 21. The power transmission mechanism 40 connects the motor 30 and the drive gear 21 so that a tilt angle θ of a second axis line A2 is variable to a first axis line A1. The first axis line A1 is an axis of rotation of the drive gear 21. The second axis line A2 is an axis of rotation of the motor 30.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an extrusion molding apparatus. [Background technology]

[0002] 2. Description of the Related Art Conventionally, an extrusion molding apparatus equipped with a gear pump for supplying molding material is known.

[0003] For example, Patent Document 1 describes a sheet manufacturing device that includes an extruder for melting a polymer, a gear pump, a die, a measuring device, and a computing device. The extruder melts the polymer, and the molten polymer is transported by a gear pump that is controlled to a constant rotation speed, and is extruded into a sheet from the die. The measuring device measures the properties of the sheet while it is being transported. The computing device controls the rotation speed of the screw of the extruder and / or the heater temperature of the extruder based on the measurement results of the measuring device.

[0004] Patent Document 2 describes a rubber extrusion molding system. This rubber extrusion molding system includes a rubber extrusion device, a rotating support, a thickness sensor, and a control unit. The rubber extrusion device includes a gear pump. The control unit sets the rotation speed of a gear in the gear pump based on the rubber extrusion speed of the rubber extrusion device.

[0005] Patent Document 3 describes a flexible tube manufacturing apparatus. This flexible tube manufacturing apparatus includes a first extruder, a second extruder, a molding device, a first gear pump, and a second gear pump. The first extruder extrudes a first resin. The second extruder extrudes a second resin that is softer than the first resin. The molding device has a first resin supply path through which the first resin is supplied from the first extruder and a second resin supply path through which the second resin is supplied from the second extruder, and extrudes the supplied resin onto the surface of the braid wire. The first gear pump is provided in the middle of the first resin supply path. The second gear pump is provided in the middle of the second resin supply path. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2014-193604 A [Patent Document 2] Patent Publication No. 2021-30618 [Patent Document 3] International Publication No. 2021 / 024794 Summary of the Invention [Problem to be solved by the invention]

[0007] As described in Patent Documents 1 to 3, in an extrusion molding device equipped with a gear pump, molding materials such as resin and rubber are supplied by the gear pump, and the supplied molding materials are molded into a predetermined shape. On the other hand, the techniques described in Patent Documents 1 to 3 have room for reexamination from the viewpoint of reducing dimensional variation of molded products when the power of a motor is transmitted to the gear pump to operate the gear pump to supply the molding material.

[0008] In view of the above circumstances, the present invention provides an extrusion molding device that is advantageous in terms of reducing dimensional variation of molded products while transmitting power from a motor to a gear pump to operate the gear pump to supply molding material. [Means for solving the problem]

[0009] The present invention relates to A die for molding the molding material; a gear pump including a drive gear and configured to supply molding material toward the die by rotation of the drive gear; A motor; a power transmission mechanism that transmits the power of the motor to the drive gear, The power transmission mechanism connects the motor and the drive gear such that an inclination angle of a second axis line, which is a rotation axis line of the motor, with respect to a first axis line, which is a rotation axis line of the drive gear, is variable. An extrusion apparatus is provided. Effect of the Invention

[0010] The above-described extrusion molding device is advantageous from the viewpoint of reducing dimensional variation of molded products while transmitting the power of the motor to the gear pump to operate the gear pump and supplying molding material. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a cross-sectional view that illustrates an example of an extrusion molding apparatus according to the present invention. [Diagram 2] FIG. 2 is an exploded perspective view showing a gear pump of the extrusion molding device shown in FIG. [Diagram 3] FIG. 3 is a cross-sectional view showing an extrusion molding apparatus according to a reference example. [Figure 4] FIG. 4 is a cross-sectional view that illustrates a schematic diagram of another example of the extrusion molding apparatus according to the present invention. [Diagram 5] FIG. 5 is a cross-sectional view that illustrates a schematic diagram of still another example of an extrusion molding apparatus according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the following description is for illustrative purposes only and is not intended to limit the present invention.

[0013] As shown in FIG. 1 and FIG. 2, the extrusion molding device 1a includes a die 10, a gear pump 20, a motor 30, and a power transmission mechanism 40. The die 10 is a component for molding a molding material. The gear pump 20 includes a drive gear 21. The gear pump 20 supplies the molding material toward the die 10 by the rotation of the drive gear 21. The power transmission mechanism 40 transmits the power of the motor 30 to the drive gear 21. As a result, the drive gear 21 rotates by the power of the motor 30, and the molding material is sent toward the die 10 by the gear pump 20. The power transmission mechanism 40 connects the motor 30 and the drive gear 21 so that the inclination angle θ of the second axis A2 with respect to the first axis A1 is variable. In other words, the inclination angle θ can be changed depending on the operating condition of the extrusion molding device 1a. The first axis A1 is the rotation axis of the drive gear 21. The drive gear 21 can rotate around the first axis A1. The second axis A2 is a rotation axis of the motor 30. The motor 30 is rotatable about the second axis A2.

[0014] FIG. 3 is a perspective view showing an extrusion molding apparatus 1x according to a reference example. The extrusion molding apparatus 1x is configured similarly to the extrusion molding apparatus 1a, except for the parts that will be particularly described. In the extrusion molding apparatus 1x, the power transmission mechanism 40 connects the motor 30 and the drive gear 21 so that the inclination angle θ of the second axis A2 relative to the first axis A1 is constant. The power transmission mechanism 40 is, for example, configured by a straight shaft extending parallel to the second axis A2. According to the study by the present inventors, it was newly found that in extrusion molding using the extrusion molding apparatus 1x, the dimensional variation of the molded product may become large. After further study, the present inventors thought that the inclination angle θ of the second axis A2 relative to the first axis A1 may affect the dimensional variation of the molded product. For example, if the inclination angle θ is large, the rotational power of the motor 30 is not normally transmitted, and the flow rate of the gear pump 20 may vary. Furthermore, the operation of the motor 30 may become overloaded, and depending on the degree of the overload, the motor 30 may break down or the power transmission mechanism 40 may be damaged.

[0015] In view of these circumstances, the inventors of the present invention have conducted extensive research into a method for reducing the dimensional variation of molded products while transmitting the power of a motor to a gear pump to operate the gear pump and supply molding material, and have newly discovered that the dimensional variation of molded products can be reduced by adopting a specific mechanism as the power transmission mechanism 40.

[0016] In the extrusion molding device 1a, the motor 30 and the drive gear 21 are connected by the power transmission mechanism 40 so that the inclination angle θ of the second axis A2 relative to the first axis A1 is variable. With this configuration, even if the inclination angle θ varies, the flow rate of the gear pump 20 is less likely to vary, and the dimensional variation of the molded product is likely to be reduced.

[0017] In the extrusion molding device 1a, the magnitude of the variable tilt angle θ is not limited to a specific value. The power transmission mechanism 40 is configured to allow the tilt angle θ to vary within a range of 8° or less (i.e., a range of ±8°), for example.

[0018] As shown in FIG. 1, the power transmission mechanism 40 includes a first shaft 43, a second shaft 44, and a coupler 45. The first shaft 43 is disposed on the first axis A1. The second shaft 44 is disposed on the second axis A2 or parallel to the second axis A2. The coupler 45 couples the first shaft 43 and the second shaft 44. The coupler 45 includes at least one ball bearing 46. With this configuration, even if the inclination angle θ varies, the flow rate of the gear pump 20 is less likely to vary, and the dimensions of the molded product are less likely to vary. The ball bearing 46 is configured, for example, so that a plurality of metal balls arranged at equal intervals around the axis can roll in a predetermined space in a direction parallel to the axis. The space in which the plurality of metal balls can roll is defined, for example, by an inner ring, a cage, and an outer ring.

[0019] The coupler 45 includes, for example, a pair of ball bearings 46, one of which is disposed near the first shaft 43 and the other of which is disposed near the second shaft 44. The coupler 45 includes, for example, an intermediate shaft 47, and the pair of ball bearings 46 are disposed near both ends of the intermediate shaft 47. For example, the coupler 45 includes at least three sets of pairs of ball bearings 46.

[0020] The coupler 45 couples the first shaft 43 and the second shaft 44, for example, so that the first shaft 43 and the second shaft 44 rotate at a constant speed regardless of the inclination angle θ. With this configuration, even if the inclination angle θ increases, the motor 30 and the drive gear 21 rotate at a constant speed, so that the amount of molding material supplied is less likely to vary, and the dimensions of the molded product are less likely to vary. The coupler 45 is configured, for example, as a constant velocity joint coupler.

[0021] 1, the gear pump 20 further includes, for example, a driven gear 22 and a casing 25. The casing 25 houses the drive gear 21. The drive gear 21 and the driven gear 22 are arranged in mesh with each other inside the casing 25. A first flow path 23 and a second flow path 24 are formed inside the casing 25. The first flow path 23 is a flow path for supplying the molding material toward the drive gear 21 and the driven gear 22, and the second flow path 23 is a flow path for supplying the molding material that has passed around the drive gear 21 and the driven gear 22 toward the outside of the gear pump 20.

[0022] As shown in FIG. 2, in the gear pump 20, the casing 25 includes, for example, a first plate 25a, a second plate 25b, and a third plate 25c. The second plate 25b is disposed between the first plate 25a and the third plate 25c in the thickness direction of the second plate 25b. The casing 25 is configured by fixing the first plate 25a, the second plate 25b, and the third plate 25c in a stacked state. The first plate 25a has a through hole 25h. The drive gear 21 includes a shaft 21a, which extends along the first axis A1. A groove 21r is formed at the tip of the shaft 21a. The shaft 21a protrudes toward the outside of the casing 25 along the through hole 25h. The tip of the shaft 21a is disposed outside the casing 25. A protrusion 41 formed to match the groove 21r is disposed at an end of the power transmission mechanism 40, and the power transmission mechanism 40 is connected to the drive gear 21 by engaging the protrusion 41 with the groove 21r. The driven gear 22 includes a stud 22a protruding along the rotation axis of the driven gear 22. A recess for accommodating the stud 22a is formed in the first plate 25a. In Fig. 2, the x-axis, y-axis, and z-axis are perpendicular to one another.

[0023] The second plate 25b has a through hole 25k for accommodating the drive gear 21 and the driven gear 22. For example, in a plan view of the second plate 25b, the through hole 25k is formed such that a pair of arcs facing each other are arranged on both sides of a portion where the drive gear 21 and the driven gear 22 mesh, and the through hole 25k has a constriction at a portion where the drive gear 21 and the driven gear 22 mesh between the pair of arcs. In the portion of the through hole 25k forming this constriction, a receiving portion 21m for receiving the molding material that has passed through the first flow path 23 and a discharging portion 21n for discharging the molding material toward the second flow path 24 are formed. The receiving portion 21m and the discharging portion 21n are partitioned by the meshing of the drive gear 21 and the driven gear 22.

[0024] The third plate 25c has a through hole 25p and a through hole 25q. The through hole 25p forms a part of the first flow path 23 and is formed at a position corresponding to the receiving portion 21m. The through hole 25q forms a part of the second flow path 24 and is formed at a position corresponding to the discharging portion 21n.

[0025] The arrows in Fig. 2 indicate the flow of the molding material. The rotational power of the motor 30 is transmitted to the drive gear 21 by the power transmission mechanism 40, and the drive gear 21 and the driven gear 22 rotate while meshing with each other. As a result, the molding material passes through the first flow path 23 and is supplied to the receiving portion 21m. Thereafter, the molding material moves through the gap between the inner wall of the through hole 25k and the drive gear 21 or the driven gear 22 as the drive gear 21 or the driven gear 22 rotates, and is discharged from the discharge portion 21n toward the second flow path 24. As a result, the gear pump 20 supplies the molding material toward the die 10. In the die 10, the molding material is molded into a predetermined shape, and a molded product is obtained.

[0026] The discharge amount of the gear pump 20 is not limited to a specific value. In the gear pump 20, the discharge amount per rotation of the drive gear 21 is, for example, 2.0 mL or less. In this case, for example, in the extrusion molding device 1x, if the inclination angle θ of the second axis A2 relative to the first axis A1 is large, the variation in dimensions of the molded product tends to increase. On the other hand, in the extrusion molding device 1a, the motor 30 and the drive gear 21 are connected by the power transmission mechanism 40 so that the inclination angle θ is variable, so that even if the discharge amount of the drive gear 21 is small, the variation in dimensions of the molded product tends to be small.

[0027] The discharge amount per one rotation of the drive gear 21 may be 3.0 mL or less, or may be 1.5 mL or less. The smaller the discharge amount, the smaller the allowable torque in power transmission to the drive gear 21 tends to be. The discharge amount is, for example, 0.03 mL or more. From the above, the discharge amount per one rotation of the drive gear 21 may be 0.03 mL or more and 3.0 mL or less, 0.03 mL or more and 2.0 mL or less, or 0.03 mL or more and 1.5 mL or less.

[0028] The molding material that can be used in the extrusion molding device 1a is not limited to a specific material. The molding material may be a thermoplastic resin, rubber, or other material that can be extruded. The molding material preferably includes a thermoplastic resin.

[0029] The shape of the molded product obtained by extrusion molding in the extrusion molding device 1a is not limited to a specific shape. The extrusion molding device 1a can mold the molding material into fiber, for example. In this case, the flow rate of the molding material supplied by the gear pump 20 often needs to be adjusted to be low, and the discharge amount of the gear pump 20 tends to be small. Even in such a case, the extrusion molding device 1a tends to reduce the dimensional variation of the molded product, which is fiber.

[0030] The molded article, the fiber, may be, for example, an optical fiber.

[0031] The shape of the molded product obtained by extrusion molding in the extrusion molding apparatus 1a may be a shape other than a fiber, such as a sheet shape, a rod shape, or a tube shape.

[0032] The extrusion molding apparatus 1a may include, for example, a heater (not shown). The type of heater and the installation location of the heater are not limited to a specific type and a specific location as long as the molding material can be molded. The heater can be disposed around the gear pump 20 and the die 10, for example.

[0033] The extrusion molding apparatus 1a further includes, for example, a controller (not shown). The controller is, for example, a digital signal processor (DSP) including an A / D conversion circuit, an input / output circuit, an arithmetic circuit, and a storage device. The controller stores a program for appropriately operating the extrusion molding apparatus 1a. In detail, the controller controls the operation of the motor 30. The controller may also control the heat generation of the heater.

[0034] In the extrusion molding device 1a, for example, the portion in contact with the molding material is made of a material that is corrosion-resistant to the molding material. In this specification, "corrosion resistance" means that the material is not substantially corroded even when it is heated in contact with the molding material. For example, when the material is heated at 300°C for 100 hours in a state in which it is in contact with the molding material, the corrosion resistance of the material is 1 cm. 2 This means that the amount of the material dissolved into the molding material per unit weight is 1 μg / g or less. By making the part in contact with the molding material out of a material having corrosion resistance, it is possible to further suppress impurities such as metals from being mixed into the molding material. The material having corrosion resistance against the molding material includes, for example, at least one selected from the group consisting of Hastelloy and Stellite. Hastelloy is an alloy containing nickel as the main component and further containing molybdenum, chromium, etc. Stellite is an alloy containing cobalt as the main component and further containing chromium, tungsten, etc. The term "main component" refers to the component that is contained most in the alloy in the mentioned alloy by mass ratio.

[0035] In the extrusion molding apparatus 1a, examples of the parts that come into contact with the molding material are the part in contact with the first flow path 23, the part in contact with the second flow path 24, the inner surface of the casing 25 of the gear pump, the surface of the drive gear 21, and the surface of the driven gear 22. Desirably, the inner surface of the casing 25, the surface of the drive gear 21, and the surface of the driven gear 22 are made of a material that is corrosion-resistant to the molding material. For example, these surfaces are formed of a coating or a thin layer made of a material that is corrosion-resistant to the molding material.

[0036] The casing 25, the driving gear 21, and the driven gear 21 may each be entirely made of a material having corrosion resistance against the molding material. The content of Hastelloy or Stellite in these members is, for example, 50% by mass or more, desirably 80% by mass or more, and more desirably 90% by mass or more. These members may be substantially made of Hastelloy or Stellite only.

[0037] The extrusion molding apparatus 1a can be modified from various viewpoints. For example, the extrusion molding apparatus 1a may be modified to an extrusion molding apparatus 1b shown in FIG. 4 or an extrusion molding apparatus 1c shown in FIG. 5. The extrusion molding apparatuses 1b and 1c are configured similarly to the extrusion molding apparatus 1a, except for the parts that will be particularly described. The components of the extrusion molding apparatuses 1b and 1c that are the same as or correspond to the components of the extrusion molding apparatus 1a are given the same reference numerals, and detailed description will be omitted. The description of the extrusion molding apparatus 1a also applies to the extrusion molding apparatuses 1b and 1c, unless there is a technical contradiction.

[0038] 4, in the power transmission mechanism 40 of the extrusion molding device 1b, the coupler 45 includes one ball bearing 46. Even with such a configuration, the inclination angle θ can be varied, and the flow rate of the gear pump 20 is less likely to vary, and the dimensions of the molded product are less likely to vary. The coupler 45 is configured as, for example, a Rzeppa type constant velocity joint coupler.

[0039] 5, the extrusion molding apparatus 1c can, for example, mold a molding material into a fiber 7. The fiber 7 has a cross section in which multiple layers are concentrically arranged. The cross section is perpendicular to the length of the fiber 7. The fiber 7 can be, for example, an optical fiber.

[0040] The extrusion molding apparatus 1c includes, for example, a first gear pump 20a, a second gear pump 20b, and a third gear pump 20c as the gear pumps 20. The extrusion molding apparatus 1c includes a motor 30 and a power transmission mechanism 40 corresponding to each of the first gear pump 20a, the second gear pump 20b, and the third gear pump 20c.

[0041] The fiber 7 has multiple layers, for example, a core 7a, a clad 7b, and a coating layer 7c. The coating layer 7c forms the outermost layer of the fiber 7, and the clad 7b is disposed inside the coating layer 7c. The core 7a is disposed inside the clad 7b. The first gear pump 20a supplies a molding material 3a for the core 7a toward the die 10. The second gear pump 20b supplies a molding material 3b for the clad 7b toward the die 10. The third gear pump 20c supplies a molding material 3c for the coating layer 7c toward the die 10.

[0042] At least one of the layers in the fiber 7 contains, for example, a fluororesin, which allows the fiber 7 to exhibit desired optical performance and durability. For example, the core 7a contains a fluororesin.

[0043] The fluororesin includes, for example, a fluorine-containing polymer (polymer (P)). From the viewpoint of suppressing light absorption due to the stretching energy of C-H bonds, the polymer (P) preferably does not substantially contain hydrogen atoms. More preferably, in the polymer (P), all hydrogen atoms bonded to carbon atoms are substituted with fluorine atoms. In this specification, "polymer (P) does not substantially contain hydrogen atoms" means that the content of hydrogen atoms in the polymer (P) is 1 mol % or less.

[0044] The polymer (P) has, for example, a fluorine-containing alicyclic structure. The fluorine-containing alicyclic structure may be contained in the main chain of the polymer (P) or in the side chain of the polymer (P). The polymer (P) has, for example, a structural unit (A) represented by the following formula (1).

[0045] [ka]

[0046] In formula (1), R ff 1 ~R ff 4R each independently represents a fluorine atom, a perfluoroalkyl group having 1 to 7 carbon atoms, or a perfluoroalkyl ether group having 1 to 7 carbon atoms. ff 1 and R ff 2 may be linked to form a ring. "Perfluoro" means that all hydrogen atoms bonded to carbon atoms are substituted with fluorine atoms. In formula (1), the number of carbon atoms in the perfluoroalkyl group is preferably 1 to 5, more preferably 1 to 3, and even more preferably 1. The perfluoroalkyl group may be linear or branched. Examples of the perfluoroalkyl group include a trifluoromethyl group, a pentafluoroethyl group, and a heptafluoropropyl group.

[0047] In the formula (1), the number of carbon atoms in the perfluoroalkyl ether group is preferably 1 to 5, and more preferably 1 to 3. The perfluoroalkyl ether group may be linear or branched. Examples of the perfluoroalkyl ether group include a perfluoromethoxymethyl group.

[0048] R ff 1 and R ff 2 When they are linked to form a ring, the ring may be a 5-membered ring or a 6-membered ring. Examples of the ring include a perfluorotetrahydrofuran ring, a perfluorocyclopentane ring, and a perfluorocyclohexane ring.

[0049] Specific examples of the structural unit (A) include structural units represented by the following formulas (A1) to (A8). [ka]

[0050] Of the structural units represented by the above formulas (A1) to (A8), the structural unit (A) is preferably the structural unit (A2), that is, the structural unit represented by the following formula (2). [ka]

[0051] The polymer (P) may contain one or more types of structural units (A). In the polymer (P), the content of the structural units (A) is preferably 20 mol% or more, more preferably 40 mol% or more, based on the total of all structural units. By containing 20 mol% or more of the structural units (A), the polymer (P) tends to have higher heat resistance. When the structural units (A) are contained in an amount of 40 mol% or more, the polymer (P) tends to have higher transparency and high mechanical strength in addition to high heat resistance. In the polymer (P), the content of the structural units (A) is preferably 95 mol% or less, more preferably 70 mol% or less, based on the total of all structural units.

[0052] The structural unit (A) is derived from a compound represented by the following formula (3), for example. ff 1 ~R ff 4 is the same as formula (1). The compound represented by formula (3) can be obtained by a known production method, for example, the production method disclosed in JP-A-2007-504125. [ka]

[0053] Specific examples of the compound represented by the above formula (3) include compounds represented by the following formulae (M1) to (M8). [ka]

[0054] The polymer (P) may further contain other structural units in addition to the structural unit (A). Examples of the other structural units include the following structural units (B) to (D).

[0055] The structural unit (B) is represented by the following formula (4). [ka]

[0056] In formula (4), R 1 ~R 3 Each independently represents a fluorine atom or a perfluoroalkyl group having 1 to 7 carbon atoms. 4 represents a perfluoroalkyl group having 1 to 7 carbon atoms. The perfluoroalkyl group may have a ring structure. Some of the fluorine atoms may be substituted with halogen atoms other than fluorine atoms. Some of the fluorine atoms in the perfluoroalkyl group may be substituted with halogen atoms other than fluorine atoms.

[0057] The polymer (P) may contain one or more types of structural units (B). In the polymer (P), the content of the structural units (B) is preferably 5 to 10 mol% based on the total of all structural units. The content of the structural units (B) may be 9 mol% or less, or may be 8 mol% or less.

[0058] The structural unit (B) is derived from a compound represented by the following formula (5), for example. 1 ~R 4 is the same as formula (4). The compound represented by formula (5) is a fluorine-containing vinyl ether such as perfluorovinyl ether. [ka]

[0059] The structural unit (C) is represented by the following formula (6). [ka]

[0060] In formula (6), R 5 ~R 8each independently represents a fluorine atom or a perfluoroalkyl group having 1 to 7 carbon atoms. The perfluoroalkyl group may have a ring structure. Some of the fluorine atoms may be substituted with halogen atoms other than fluorine atoms. Some of the fluorine atoms in the perfluoroalkyl group may be substituted with halogen atoms other than fluorine atoms.

[0061] The polymer (P) may contain one or more types of structural units (C). In the polymer (P), the content of the structural units (C) is preferably 5 to 10 mol% based on the total of all structural units. The content of the structural units (C) may be 9 mol% or less, or may be 8 mol% or less.

[0062] The structural unit (C) is derived from a compound represented by the following formula (7), for example: 5 ~R 8 is the same as formula (6). The compound represented by formula (7) is a fluorine-containing olefin such as tetrafluoroethylene and chlorotrifluoroethylene. [ka]

[0063] The structural unit (D) is represented by the following formula (8). [ka]

[0064] In formula (8), Z is an oxygen atom, a single bond, or -OC(R 19 R 20 )O-, R 9 ~R 20each independently represents a fluorine atom, a perfluoroalkyl group having 1 to 5 carbon atoms, or a perfluoroalkoxy group having 1 to 5 carbon atoms. Some of the fluorine atoms may be substituted with halogen atoms other than fluorine atoms. Some of the fluorine atoms in the perfluoroalkyl group may be substituted with halogen atoms other than fluorine atoms. Some of the fluorine atoms in the perfluoroalkoxy group may be substituted with halogen atoms other than fluorine atoms. s and t each independently represent an integer of 0 to 5, and s+t is an integer of 1 to 6 (with the proviso that Z is -OC(R 19 R 20 )O-, s+t may be 0.

[0065] The structural unit (D) is preferably represented by the following formula (9): The structural unit represented by the following formula (9) is the case where Z is an oxygen atom, s is 0, and t is 2 in the above formula (8). [ka]

[0066] In formula (9), R 141 , R 142 , R 151 , and R 152 each independently represents a fluorine atom, a perfluoroalkyl group having 1 to 5 carbon atoms, or a perfluoroalkoxy group having 1 to 5 carbon atoms. Some of the fluorine atoms may be substituted with halogen atoms other than fluorine atoms. Some of the fluorine atoms in the perfluoroalkyl group may be substituted with halogen atoms other than fluorine atoms. Some of the fluorine atoms in the perfluoroalkoxy group may be substituted with halogen atoms other than fluorine atoms.

[0067] The polymer (P) may contain one or more types of structural unit (D). In the above, the content of the structural unit (D) is preferably 30 to 67 mol % relative to the total amount of all structural units. The content of the structural unit (D) is, for example, 35 mol % or more, and may be 60 mol % or less, or may be 55 mol % or less.

[0068] The structural unit (D) is derived from a compound represented by the following formula (10): 9 ~R 18 , s and t are the same as in equation (8). The compound is a fluorine-containing compound which has two or more polymerizable double bonds and is capable of cyclopolymerization. [ka]

[0069] The structural unit (D) is preferably derived from a compound represented by the following formula (11): 141 , R 142 , R 151 , and R 152 is the same as equation (9). [ka]

[0070] Specific examples of the compound represented by formula (10) or formula (11) include the following compounds. CF2=CFCF2CF=CF2 CF2=CFOCF(CF3)CF=CF2 CF2=CF2CF2CF=CF2 CF2=CF0CF2CF(CF3)CF=CF2 CF2=CFFOCF(CF3)CF2CF=CF2 CF2=CFOCFClCF2CF=CF2 CF2=CFOCCl2CF2CF=CF2 CF2=CFOCF2OCF=CF2 CF2=CFOC(CF3)2OCF=CF2 CF2=CF2CF(OCF3)CF=CF2 CF2=CFCF2CF=CF2 CF2=CFCF2CF2CF=CF2 CF2=CFCF2OCF2CF=CF2 CF2=CFOCF2CFClCF=CF2 CF2=CFOCF2CF2CCl=CF2 CF2=CFOCF2CF2CF=CFCl CF2=CFOCF2CF(CF3)CCl=CF2 CF2=CFOCF2OCF=CF2 CF2=CFOCCl2OCF=CF2 CF2=CClOCF2OCCl=CF2

[0071] The polymer (P) may further contain other structural units besides the structural units (A) to (D), but preferably does not substantially contain other structural units than the structural units (A) to (D). Here, the polymer (P) being substantially free of structural units other than the structural units (A) to (D) means that the total of the structural units (A) to (D) is 95 mol % or more, and preferably 98 mol % or more, of the total of all structural units in the polymer (P).

[0072] The polymerization method for the polymer (P) is not particularly limited, and for example, a general polymerization method such as radical polymerization can be used. The polymerization initiator for polymerizing the polymer (P) may be a perfluorinated compound.

[0073] The glass transition temperature (Tg) of the polymer (P) is not particularly limited and is, for example, 100° C. to 140° C., and may be 105° C. or higher, or 120° C. or higher. In this specification, Tg refers to the midpoint glass transition temperature (T mg )

[0074] The molding material 3a may contain the polymer (P) as a main component, or may be substantially composed of only the polymer (P). The molding material 3a may further contain an additive such as a refractive index adjuster. The molding material 3a is, for example, solid at room temperature (25°C).

[0075] The refractive index of the clad 7b is, for example, lower than that of the core 7a. Examples of the molding material 3b for the clad 7b include fluorine-containing resin, acrylic resin such as methyl methacrylate, styrene resin, and carbonate resin. Examples of the molding material 3c for the coating layer 7c include polycarbonate, various engineering plastics, cycloolefin polymer, polytetrafluoroethylene (PTFE), modified PTFE, and perfluoroalkoxyalkane (PFA).

[0076] The outer diameter of the fiber 7 and the outer diameter of the core 7a are not limited to a specific value. The outer diameter of the fiber 7 is, for example, 100 μm or more and 1000 μm or less, and preferably 150 μm or more and 600 μm or less. The outer diameter of the core 7a is, for example, 5 μm or more and 100 μm or less, and preferably 10 μm or more and 80 μm or less.

[0077] As shown in FIG. 5, the extrusion molding apparatus 1c includes, for example, a first tank 2a, a second tank 2b, and a hopper 2c. Each of the first tank 2a and the second tank 2b is, for example, cylindrical. With the molding material 3a and the molding material 3b accommodated inside the first tank 2a and the second tank 2b, respectively, the first tank 2a and the second tank 2b are closed by a lid 2m. A pipe 2p is connected to the lid 2m. Gas is supplied to the inside of the first tank 2a and the second tank 2b through the pipe 2p. The gas is, for example, an inert gas such as nitrogen gas. The pipe 2p is, for example, connected to a high-pressure gas cylinder (not shown), and the pressure inside the first tank 2a and the second tank 2b can be adjusted by operating a pressure reducing valve.

[0078] The first tank 2a and the second tank 2b contain, for example, molding materials 3a and 3b molded into a rod shape, respectively. The rod-shaped molding materials 3a and 3b are softened and made flowable by, for example, being heated. When gas passes through the pipe 2p and is introduced into the inside of the first tank 2a and the second tank 2b, the flowable molding materials 3a and 3b are pressurized by the gas and flow toward the first gear pump 20a and the second gear pump 20b, respectively. When the first gear pump 20a and the second gear pump 20b are operated, the molding materials 3a and 3b pass through the first gear pump 20a and the second gear pump 20b, respectively, and are supplied to the die 10. The temperature at which the molding materials 3a and 3b are heated is not limited to a specific temperature as long as the fiber 7 can be obtained. The temperature is, for example, 100°C or higher and 250°C or lower. The viscosity of the molding materials 3a and 3b discharged from the first gear pump 20a and the second gear pump 20b is not limited to a specific temperature as long as the fiber 7 can be obtained. The viscosity is, for example, 1 Pa·s or more and 7000 Pa·s or less, desirably 500 Pa·s or more and 7000 Pa·s or less, more desirably 5000 Pa·s or less, and even more desirably 3000 Pa·s or less.

[0079] The pellet-like molding material 3c is fed into a hopper 2c and guided into the cylinder 2s. A screw 2t is disposed inside the cylinder 2s. The molding material 3c is kneaded and softened by the screw 2t while being heated inside the cylinder 2s, and becomes flowable. The softened molding material 3c passes through the cylinder 2s by the screw 2t. The molding material 3c that has passed through the cylinder 2s is discharged toward the die 10 through the third pump 20c by the operation of the third pump 20c.

[0080] In the die 10, the molding material 3a is molded into a fiber shape. The molding material 3b is supplied toward the molding material 3a molded into a fiber shape, and the molding material 3a molded into a fiber shape is surrounded by the molding material 3b. Then, the molding material 3c is supplied toward the molding material 3b, and the molding material 3b is surrounded by the molding material 3c. In this manner, the molding material 3a, the molding material 3b, and the molding material 3c are discharged from the die 10 in a state in which the layer of the molding material 3a, the layer of the molding material 3b, and the layer of the molding material 3c are concentrically arranged. The extrusion molding device 1c is provided with, for example, a cooling tube 4 in contact with the discharge port of the die 10. The molding material 3a, the molding material 3b, and the molding material 3c discharged from the die 10 are cooled by passing through the inside of the cooling tube 4. As a result, the fiber 7 is obtained. The fiber 7 is then wound at a predetermined speed.

[0081] 5, the extrusion molding apparatus 1c further includes, for example, a measuring device 5. The measuring device 5 measures, for example, the outer diameter of the fiber 7. The measuring device 5 measures, for example, the outer diameter of the fiber 7 immediately before being wound. The measuring device 5 is, for example, an optical dimension measuring device.

[0082] In the extrusion molding apparatus 1c, a three-layered fiber 7 having a core 7a, a clad 7b, and a coating layer 7c can be produced. The manufacturing apparatus 1c may be configured to produce a two-layered fiber consisting of a core and a clad. EXAMPLES

[0083] The present invention will be described in more detail below with reference to examples, although the present invention is not limited to the following examples.

[0084] <Example 1> An extrusion molding apparatus according to the embodiment having the same configuration as the extrusion molding apparatus 1c shown in FIG. 5 was prepared. In the extrusion molding apparatus according to the embodiment, the gear pump SDS-9-0.1 manufactured by Kyowa Finetech Co., Ltd. was used as the first gear pump 20a and the second gear pump 20b, and the HDS-18-1.2 manufactured by the same company was used as the third gear pump 20c. In the first gear pump 20a and the second gear pump 20b, the discharge amount per rotation of the drive gear 21 was 0.1 mL. In the third gear pump 20c, the discharge amount per rotation of the drive gear 21 was 1.2 mL. A constant velocity joint (model number: C0008D-B) manufactured by NKK Co., Ltd. was used as the power transmission mechanism 40 to connect the drive gear 21 and the motor 30 in the first gear pump 20a, the second gear pump 20b, and the third gear pump 20c. A motor HG-KR23 manufactured by Mitsubishi Electric Co., Ltd. was used as the motor 30. The cooling pipe 4 was kept at 10°C by cooling. In the extrusion molding apparatus according to the embodiment, a dimension measuring instrument LS-9006 manufactured by Keyence Corporation was used as the measuring instrument 5. In the extrusion molding apparatus according to the embodiment, the inclination angle θ of the rotation axis A2 of the motor 30 with respect to the rotation axis A1 of the drive gear was adjusted to 0.5°. This inclination angle θ was calculated using images of the gear pump 20 and the motor 30 taken from multiple fields of view.

[0085] As the molding material 3a, perfluoro-4-methyl-2-methylene-1,3-dioxolane, a fluororesin, was placed in the first tank 2a, and the inside of the first tank 2a was sealed with a lid 2m. The amount of the fluororesin placed in the first tank 2a was 300g. As the molding material 3b, a solid-state mixture of fluororesin AF1600 manufactured by Mitsui-Chemours Fluoroproducts and Fomblin (YR grade), a functionalized perfluoropolyether manufactured by SOLVAY, was placed in the second tank 2b, and the inside of the second tank 2b was sealed with a lid 2m. The amount of the mixture placed in the second tank 2b was 300g. The contents of the fluororesin AF1600 and Fomblin in the mixture were 70% by mass and 30% by mass, respectively. The extrusion molding apparatus according to the embodiment was heated for 12 hours, and each part was adjusted to a predetermined temperature. The first tank 2a and the first gear pump 20a were heated to 250°C by a heater. The second tank 2b and the second gear pump 20b were heated to 255°C by a heater. The cylinder 2s and the third gear pump 20c were heated to 240°C by a heater. The part of the die 10 through which only the molding material 3a passes was heated to 250°C by a heater. The part of the die 10 through which the molding material 3b is supplied was heated to 260°C by a heater. The part of the die 10 through which the moldable material 3a surrounded by the molding material 3b passes was heated to 260°C by a heater. The part of the die 10 through which the molding material 3c is supplied was heated to 250°C by a heater. The part of the die 10 through which the molding materials 3a, 3b, and 3c are discharged was heated to 240°C by a heater.

[0086] Compressed air was sent into the first tank 2a and the second tank 2b to pressurize them, and the molding material 3a and the molding material 3b were supplied to the first gear pump 20a and the second gear pump 20b, respectively. The pressure of the compressed air was adjusted to 0.2 MPa. Next, Xylex 7200 manufactured by Sabic, which had been dried in advance for 5 hours in an environment of 100°C, was put into the hopper 2c, nitrogen was supplied to the hopper 2c in a steady state, and the screw 2t was rotated at 3 revolutions per minute (rpm). The amount of Xylex 7200 put in was 5 kg. Xylex 7200 is a polymer blend containing polycarbonate (PC) and amorphous polyester.

[0087] Next, the first gear pump 20a, the second gear pump 20b, and the third gear pump 20c were rotated at rotation speeds of 0.3 rpm, 0.5 rpm, and 1.4 rpm, respectively, to supply the molding materials 3a, 3b, and 3c to the die 10. The molding materials 3a, 3b, and 3c discharged from the die 10 were passed through a cooling tube 4 to obtain the fiber according to Example 1. Thereafter, the fiber according to Example 1 was wound up at a speed of 40 m / min. Just before winding, the outer diameter of the fiber according to Example 1 was measured by a measuring device 5 at predetermined time intervals. As a result, the average value of the outer diameter of the fiber according to Example 1 was 230 μm. In addition, the load of the motor 30 when the gear pump 20 was rotating was evaluated by recording the current value for 1 second obtained from the load signal of the motor 30.

[0088] Based on data obtained by measuring the outer diameter of the fiber according to Example 1 at 1 second intervals for 3 hours, 3σ / Ave. and the difference obtained by subtracting the minimum value from the maximum value were calculated. σ is the standard deviation of the measurement data of the outer diameter of the fiber, and Ave. is the arithmetic mean value of the outer diameter of the fiber. The average value and the difference obtained by subtracting the minimum value from the maximum value of the load of the motor 30 corresponding to each gear pump 20 were calculated. The results are shown in Table 1.

[0089] <Example 2> A fiber according to Example 2 was obtained in the same manner as in Example 1, except that the inclination angle θ of the rotation axis A2 of the motor 30 relative to the rotation axis A1 of the drive gear in the extrusion molding apparatus according to the example was adjusted to 2°. The outer diameter and motor load of the fiber according to Example 2 were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0090] <Example 3> A fiber according to Example 3 was obtained in the same manner as in Example 1, except that the inclination angle θ of the rotation axis A2 of the motor 30 relative to the rotation axis A1 of the drive gear in the extrusion molding apparatus according to the example was adjusted to 3°. The outer diameter and motor load of the fiber according to Example 3 were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0091] <Comparative Example 1> An extrusion molding device according to a comparative example was prepared in the same manner as in Example 1, except that a straight shaft manufactured by the company was used instead of the constant velocity joint C00008D-B manufactured by NKK Corporation. The maximum diameter of the straight shaft was 20 mm, and the length of the straight shaft was 155 mm. In the extrusion molding device according to the comparative example, the inclination angle θ of the rotation axis A2 of the motor 30 with respect to the rotation axis A1 of the drive gear was 0.5°. A fiber according to Comparative Example 1 was obtained in the same manner as in Example 1, except that this extrusion molding device was used. The outer diameter of the fiber according to Comparative Example 1 and the load of the motor were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0092] <Comparative Example 2> A fiber according to Comparative Example 2 was obtained in the same manner as Comparative Example 1, except that the inclination angle θ of the rotation axis A2 of the motor 30 relative to the rotation axis A1 of the drive gear in the extrusion molding device according to the comparative example was adjusted to 2°. The outer diameter and motor load of the fiber according to Comparative Example 2 were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0093] As shown in Table 1, the 3σ / Ave. of the outer diameter of the fiber and the difference obtained by subtracting the minimum value from the maximum value in the examples 1 to 3 were small, and no clear correlation was observed between these values ​​and the magnitude of the inclination angle θ. On the other hand, the 3σ / Ave. of the outer diameter of the fiber in the comparative example 1 and the difference obtained by subtracting the minimum value from the maximum value were relatively small, whereas the 3σ / Ave. of the outer diameter of the fiber in the comparative example 2 and the difference obtained by subtracting the minimum value from the maximum value were relatively large. It is considered that the inclination angle θ in the comparative example 2 was larger than that in the comparative example 1, which resulted in the 3σ / Ave. of the outer diameter of the fiber and the difference obtained by subtracting the minimum value from the maximum value being relatively large. A comparison between the examples and the comparative examples suggested that it is advantageous to use a mechanism capable of varying the inclination angle θ, such as a constant velocity joint, as a power transmission mechanism in order to reduce the dimensional variation of a molded product such as a fiber.

[0094] [Table 1]

[0095] The first aspect of the present invention is A die for molding the molding material; a gear pump including a drive gear and configured to supply molding material toward the die by rotation of the drive gear; A motor; a power transmission mechanism that transmits the power of the motor to the drive gear, The power transmission mechanism connects the motor and the drive gear such that an inclination angle of a second axis line, which is a rotation axis line of the motor, with respect to a first axis line, which is a rotation axis line of the drive gear, is variable. An extrusion apparatus is provided.

[0096] A second aspect of the present invention is the power transmission mechanism includes a first shaft arranged on the first axis, a second shaft arranged on the second axis or parallel to the second axis, and a coupler connecting the first shaft and the second shaft, the coupling includes at least one ball bearing; According to a first aspect, an extrusion device is provided.

[0097] A third aspect of the present invention is the power transmission mechanism includes a first shaft arranged on the first axis, a second shaft arranged on the second axis or parallel to the second axis, and a coupler connecting the first shaft and the second shaft, The coupler couples the first shaft and the second shaft so that the first shaft and the second shaft rotate at a constant speed regardless of the inclination angle. According to a first aspect, an extrusion device is provided.

[0098] A fourth aspect of the present invention is The gear pump has a discharge volume of 3.0 mL or less per rotation of the drive gear. The present invention provides an extrusion molding device according to any one of the first to third aspects.

[0099] A fifth aspect of the present invention is The molding material includes a thermoplastic resin. The present invention provides an extrusion molding device according to any one of the first to fourth aspects.

[0100] A sixth aspect of the present invention is The die is capable of forming the molding material into a fiber. The present invention provides an extrusion molding device according to any one of the first to fifth aspects.

[0101] A seventh aspect of the present invention is The fiber is an optical fiber. According to a sixth aspect, there is provided an extrusion apparatus.

[0102] An eighth aspect of the present invention is the fiber has a cross-section with multiple concentrically arranged layers; the cross section is perpendicular to the length of the fiber; According to a sixth aspect, there is provided an extrusion apparatus.

[0103] A ninth aspect of the present invention is At least one of the layers contains a fluororesin. According to an eighth aspect, there is provided an extrusion apparatus. [Explanation of symbols]

[0104] 1a, 1b, 1c Extrusion molding device 7 Fiber 10 Die 20 Gear Pump 21 Drive gear 25 Casing 30 Motor 40 Power transmission mechanism 43 First Shaft 44 Second Shaft 45 Coupler 46 Ball Bearings

Claims

1. A die for molding the molding material; a gear pump including a drive gear and configured to supply molding material toward the die by rotation of the drive gear; A motor; a power transmission mechanism that transmits the power of the motor to the drive gear, The power transmission mechanism connects the motor and the drive gear such that an inclination angle of a second axis, which is a rotation axis of the motor, with respect to a first axis, which is a rotation axis of the drive gear, is variable. Extrusion molding equipment.

2. the power transmission mechanism includes a first shaft arranged on the first axis, a second shaft arranged on the second axis or parallel to the second axis, and a coupler connecting the first shaft and the second shaft, the coupling includes at least one ball bearing; 2. The extrusion molding apparatus of claim 1.

3. the power transmission mechanism includes a first shaft arranged on the first axis, a second shaft arranged on the second axis or parallel to the second axis, and a coupler connecting the first shaft and the second shaft, The coupler couples the first shaft and the second shaft so that the first shaft and the second shaft rotate at a uniform speed regardless of the inclination angle.

2. The extrusion molding apparatus of claim 1.

4. The gear pump has a discharge volume of 3.0 mL or less per rotation of the drive gear.

2. The extrusion molding apparatus of claim 1.

5. The molding material includes a thermoplastic resin. An extrusion molding apparatus according to any one of claims 1 to 4.

6. The die is capable of forming the molding material into a fiber.

6. The extrusion molding apparatus according to claim 5.

7. The fiber is an optical fiber.

7. The extrusion molding apparatus according to claim 6.

8. the fiber has a cross-section with multiple concentrically arranged layers; the cross section is perpendicular to the length of the fiber; 7. The extrusion molding apparatus according to claim 6.

9. At least one of the layers contains a fluororesin.

9. The extrusion molding apparatus of claim 8.

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