JP2668849C - - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a spinneret, and more particularly, to a spinneret having a spinneret which prevents stagnation in the spinneret and reduces pressure loss of the spinneret. It relates to a manufacturing method. 2. Description of the Related Art A spinneret is usually formed by providing a disk member made of steel, particularly stainless steel, with a large number of spinning holes of a predetermined shape. When the cross section of the yarn to be spun is round, the spinning hole is formed as shown in FIGS. 10 and 11, for example, and a modified cross section (cross section other than round, for example, Y, star, cross, triangle, etc.) In the case of ()), the spinning holes are formed as shown in FIGS. 12 and 13, for example. In FIGS. 10 and 12, reference numerals 101 and 111 denote partial longitudinal sections of a disk member constituting a spinneret, and a predetermined number of spinning holes 1 are formed in the disk members 101 and 111.
02 and 112 are formed. The arrows indicate the flow direction of the molten fluid, for example, the molten synthetic resin. The spinning holes 102 and 112 are, in order from the upstream side, introduction portions 103 and 113 having a circular cross section and a tapered inner peripheral surface, and introduction holes 104 and 114 formed of straight holes having a circular cross section. Throttle portions 105 and 115 each having a circular surface and an inner peripheral surface formed as a tapered surface; a discharge hole portion 106 having the same shape in the hole extending direction;
116. In the case of a round cross-section yarn, the cross section of the discharge hole 106 is formed in a circular shape as shown in FIG.
The section 6 is formed in a Y-shaped section, for example, as shown in FIG. [0004] Of the spinning holes 102, 112, in particular, the ejection holes 106, 116 require extremely high finishing accuracy, and have a hole diameter (hole maximum diameter) of 0.1 to 1.0 m.
Since the diameter must be as small as about m, and particularly in the case of a yarn cap with a modified cross section, the hole cross section has a modified cross section, so that the discharge holes 106 and 116 are usually formed by electric discharge machining. That is, machining and finishing are performed by drilling, reaming, and the like up to the narrowed portions 105 and 115, and the discharge holes 106 and 116 are formed by electric discharge machining. However, the conventional spinneret in which the spinning holes 102 and 112 are formed by the above-described processing method has the following problems. First, as for the yarn cap with a round cross-section shown in FIGS. 10 and 11, as shown in FIG. 10, since the vertical cross-sectional shape is a polygonal line, a smooth flow of the molten fluid is particularly observed at the bend. Is difficult to obtain, which leads to an increase in pressure loss and, in some cases, there is a possibility of local retention. [0006] In the case of the yarn cap with a modified cross-section shown in Figs. 12 and 13, such a problem becomes extremely large. That is, due to processing, the entrance of the discharge hole 116, that is, the discharge hole 11
A flat surface 117 is inevitably formed at the boundary between the diaphragm 6 and the throttle portion 115, and the flat surface 117 remains as shown in the figure even after the processing of the discharge hole portion 116. Since the flat surface 117 is a surface that is substantially perpendicular to the flow direction of the molten fluid, stagnation is likely to occur in this portion and causes a large pressure loss. [0007] When the stagnation occurs, there is a possibility that a production trouble such as yarn breakage of the spun yarn may be caused, or a problem in yarn quality may be caused. When the pressure loss increases, a higher pressure is required at the spinneret inlet, so that the spinneret portion and each component on the upstream side thereof need to have higher pressure resistance. In the conventional machining method described above, since the discharge holes 106 and 116 must be subjected to electric discharge machining one by one, it takes time and effort for machining, and the spinneret becomes expensive. At the same time, due to processing variations, the finished discharge holes 106 and 11
The hole accuracy of No. 6 may vary. When this variation increases, quality problems and troubles of the spun yarn are caused. It is an object of the present invention to provide a method for producing a spinneret having a spinning hole capable of substantially completely eliminating stagnation and suppressing pressure loss to an extremely low level. is there. Another object of the present invention is to provide a method for producing a spinneret which can be easily manufactured at a low cost and which can facilitate the boring and greatly reduce the processing time. [0011] According to the method of the present invention for producing a spinneret according to the present invention, there is provided an introduction hole into which a molten fluid is introduced, and the molten fluid is discharged from the introduction hole. In the method for manufacturing a spinning die having a large number of spinning holes having a discharge hole portion having a diameter smaller than the introduction hole portion, each spinning hole is viewed at least in the direction of the flow of the molten fluid, and at least the discharge hole on the inner surface of the spinning hole Connect to department entrance
A portion, formed into a three-dimensional curved surface substantially discharge hole inlet shape line does not appear, the respective spinning holes, thereby forming in each ceramic member, the ceramic member, is formed in the base body A pin-shaped mold having a curved surface portion corresponding to the three-dimensional curved surface at a predetermined outer peripheral portion is formed by fixing a spinning hole in each of the mounting holes and a spinning hole in each ceramic member. The method is characterized in that ceramic powder is formed into a predetermined member shape on a mold, and is formed by firing. In other words, the spinning hole inner surface, which has conventionally been formed in a polygonal line shape when viewed in the hole longitudinal section, has a smooth three-dimensional curved surface (curved in the vertical sectional shape) at least at a portion connected to the discharge hole entrance. The three-dimensional curved surface portion is smoothly connected to the discharge hole entrance so that the shape line of the discharge hole entrance does not substantially appear. In the spinneret, each spinning hole is formed in each ceramic member, and the ceramic member is attached to each mounting hole formed in a die body made of, for example, a metal disk member. By being respectively fixed inside, it can be manufactured practically and easily. That is, the spinneret body and the spinning hole forming section are made of members made of different materials, and both are joined. As the spinning hole forming member, a ceramic member is optimal in view of heat resistance, pressure resistance, and moldability. A pin-shaped molding die having a curved surface portion corresponding to the three-dimensional curved surface at a predetermined outer peripheral portion is manufactured, and ceramic powder is molded into a predetermined member shape (for example, injection molded) on the pin-shaped molding die, and then fired. This makes it possible to easily obtain a large number of ceramic members having a predetermined spinning hole shape without subjecting individual holes to electric discharge machining as in the related art. If necessary, a modification process for improving the hole accuracy may be performed. A target spinneret is obtained by fixing the ceramic member manufactured as described above in each mounting hole formed by machining a metal disc member as a base body, for example, a metal disk member. In the method for producing a spinneret according to the present invention, the inner surface of the spinning hole, particularly the inner surface of the spinning hole which is narrowed down to a small diameter and reaches the inlet of the discharge hole, is formed into a smooth three-dimensional curved surface. Since the curved surface portion is smoothly connected to the discharge hole portion so that the discharge hole portion entrance shape line does not appear, a bent portion as in the conventional structure, or a flat surface orthogonal to the flow of the molten fluid is not formed, The danger of stagnation is eliminated and the pressure loss is greatly reduced by the smooth flow. The present invention is, of course, also effective in a die for a round cross-section yarn, but a very remarkable effect can be obtained particularly when the present invention is applied to a die for a modified cross-section yarn. That is, as shown in FIGS. 12 and 13, the possibility of stagnation is extremely strong, and there is no flat surface immediately before the discharge hole portion that causes a large pressure loss, so there is no danger of stagnation in this portion. At the same time, the flow becomes extremely smooth despite being reduced to a small diameter at the three-dimensional curved surface portion, and the pressure loss is greatly reduced. In addition, each spinning hole is formed in each ceramic member, and the ceramic member is fixed in each mounting hole formed in the die body, and the spinning hole in each ceramic member is formed. Since a pin-shaped molding die having a curved surface portion corresponding to the three-dimensional curved surface at a predetermined outer peripheral portion is manufactured, a ceramic powder is formed on the pin-shaped molding die into a predetermined member shape, and it is formed by firing. Therefore, a ceramic member having a spinning hole of a predetermined shape can be easily and mass-produced in a short time by using the same pin-shaped forming die without relying on electric discharge machining as in the prior art. Can be easily manufactured. Preferred embodiments of the method for producing a spinneret according to the present invention will be described below with reference to the drawings. FIGS. 1 to 4 show a spinneret manufactured by the method according to the first embodiment of the present invention, and show a case where the present invention is applied to a nozzle with a modified cross-section. FIG.
In FIG. 2 and FIG. 2, 1 indicates the entire spinneret. The spinneret 1 has a metal disc member 2 as a spinneret main body, and a predetermined number (number of spinning holes) of the metal disc member 2 and a mounting hole 3 formed in a predetermined arrangement. And a ceramic member 5 having a spinning hole 4 fixed thereto. The material of the metal disk member 2 is not particularly limited as long as it has heat resistance, pressure resistance, corrosion resistance and the like required for the spinneret. Therefore, stainless steel conventionally used for a spinneret can be used. Further, in the present embodiment, the metal disc portion plate 2 is used as the base body, but the material of the base body is made of another material, for example, a ceramic member formed separately from the ceramic member 5 described below. You may comprise. The material of the ceramic member 5 is not particularly limited, and a ceramic material containing alumina and zirconia can be used. Among them, zirconia ceramics having high hardness and high rigidity are preferable. The ceramic member 5 has a spinning hole 4 inside, and in this embodiment, the outer peripheral surface is formed in a stepped shape as shown in FIG. The mounting hole 3 formed in the metal disk member 2 has a fitting portion 3a for fitting with the ceramic member 5 formed at the center in the plate thickness direction. The hole diameter is larger than the outer diameter of the hole. After each ceramic member 5 is fitted into the fitting portion 3a of each mounting hole 3, a heat-resistant inorganic material is provided in a gap formed between the outer peripheral surface of the ceramic member 5 and the inner peripheral surface 3b, 3c of the mounting hole. The adhesive 6 is filled and solidified. By filling and solidifying the heat-resistant inorganic adhesive 6, the ceramic member 5 is firmly fixed in the mounting hole 3, and a gap which causes stagnation or the like is formed on the upper and lower surfaces of the spinneret. Is prevented. The heat-resistant inorganic adhesive 6 is made of a mixture of an inorganic powder, for example, a glass powder or a ceramic powder, and a heat-resistant adhesive or a binder.
It is solidified by heat treatment in a thermostat, a baking furnace, or the like. In this embodiment, the ceramic member 5 is fixed in the mounting hole 3 by using the heat-resistant inorganic adhesive 6 as described above. However, the present invention is not limited to this, and the ceramic member 5 may be fixed by another method. .
For example, a method in which the mounting hole 3 is processed into substantially the same shape as the outer peripheral shape of the ceramic member 5 over substantially the entire length, and the ceramic member 5 is press-fitted, or
The metal disk member 2 as a base body is heated to expand the diameter of the mounting hole 3 by thermal expansion, and the ceramic member 5 at room temperature or after being heated to the same temperature as the base body is fitted to the disk member. 2, a method of fixing by lowering the temperature, etc. can also be adopted. The spinning hole 4 formed in the ceramic member 5 is formed in the shape shown in FIGS. 3 and 4 in this embodiment. As shown in FIG. 3, the spinning hole 4 has a circular cross-section and an inner peripheral surface that introduces the molten fluid into the hole from an upstream side when viewed in the flow direction (arrow direction) of the molten fluid, for example, the molten synthetic resin. An introduction portion 7 formed on the tapered aperture surface, connected to the introduction portion 7, an introduction hole portion 8 formed of a straight hole portion having a circular cross section, connected to the introduction hole portion 8,
A three-dimensional curved surface portion 9 having a smooth three-dimensional curved surface, the diameter of which is reduced toward the downstream side; It is formed. In this embodiment, the irregular cross-sectional shape of the discharge hole portion 10 is formed in a Y shape as shown in FIG. The three-dimensional curved surface portion 9 changes its surface shape smoothly, and when connected to the inlet 10 a of the discharge hole 10, smoothly changes such that the shape line of the inlet 10 a of the discharge hole 10 does not substantially appear. Connected. In FIG. 3, for convenience of description, the boundaries of the holes are indicated by broken lines, but these lines do not actually appear. In the present embodiment, the three-dimensional curved surface portion 9
The boundary between the hole and the introduction hole 8 is also in a connected state via a smooth curved surface, and no shape line appears at this portion. Further, in the present embodiment, R is also provided at the boundary between the introduction portion 7 and the introduction hole portion 8, and this portion also transitions smoothly. The irregular cross-sectional shape of the discharge hole portion 10 is not limited to the above-mentioned Y-shape, and a cross-sectional shape used for a known irregular cross-section yarn, for example, a star, a cross, a triangle, or the like can be adopted. In any cross-sectional shape, at least the introduction hole and the discharge hole may be smoothly connected by the three-dimensional curved surface so that the entrance shape line of the discharge hole does not appear. The discharge hole 10 usually has a hole diameter (maximum diameter) of about 0.1 to 1.0 mm,
The length is about 0.1 to 1.0 mm, and the diameter of the introduction hole 8 is 1.0 to 5.0 m.
m. Since the discharge hole portion 10 has an irregular cross-section, the hole diameter is small, and precision is required, conventionally, only the electric discharge machining has been performed as described above. However, in the present invention, a ceramic member 5 manufactured separately from the metal disk member 2 is used as the spinning hole 4 forming member, and the ceramic members 5 are substantially the same in the same process as follows. It is easily and accurately manufactured in a short time by the method. A pin-shaped mold having an outer shape substantially the same as the shape of the spinning hole 4 as described above is manufactured, and ceramic powder (or a binder is mixed with the ceramic powder) around the pin-shaped mold. Can be manufactured by molding (compression molding, injection molding, etc.) and finishing details as required. In the spinneret manufactured as described above, the molten fluid flowing from the introduction hole 8 into the discharge hole 10 flows along the three-dimensional curved surface 9. The three-dimensional curved surface portion 9 is smoothly connected to the discharge hole portion 10 having a Y-shaped irregular cross section so that the shape line of the entrance 10a of the discharge hole portion 10 does not appear. The flow that reaches inside is also a very smooth streamline flow. In other words, the flow does not flow in a broken line state as in the conventional shape, and in particular, since the flat portion as shown in FIGS. The pressure loss is greatly reduced by the smooth and smooth flow. In this embodiment, the boundary between the introduction portion 7 and the introduction hole 8 and the boundary between the introduction hole 8 and the three-dimensional curved surface 9 are also smoothly connected. These portions also have a smooth flow state, and the pressure loss is further reduced. Furthermore, the ceramic member 5 having the spinning hole 4 can be manufactured easily, accurately, and in large quantities independently of the metal disk member 2 without using any electric discharge machining. In addition, the spinneret 1 can be manufactured in a short time and at low cost. In the above-described embodiment, the length of the three-dimensional curved surface portion 9 is relatively shortened in the flow direction of the molten fluid. However, the length may be appropriately changed. For example, a three-dimensional curved surface portion 9 may be formed from the longitudinal central portion of the introduction hole portion 8, and the three-dimensional curved surface portion 9 may be lengthened and connected to the discharge hole portion 10. As shown in a modified example in FIG. 5, a three-dimensional curved surface portion 11 is formed over the entire length from the entrance of the introduction hole portion (that is, from the exit of the introduction portion 7) to the discharge hole portion 10. You may. Further, as shown in FIG. 6, another three-dimensional curved surface portion 1 extends from the entrance of the introduction portion, that is, from the entrance of the base to the discharge hole portion 10 over the entire length.
2 may be formed. In the examples shown in FIGS. 5 and 6, from the inlet of the introduction hole,
Further, the cross-sectional shape from the inlet of the introduction portion may be similar to or similar to that of the discharge hole. Furthermore, in each of the above examples, the shape line in the vertical cross section of the three-dimensional curved surface portion is formed to be a curve, but the shape line in the vertical cross section may be formed to be linear. The length of the three-dimensional curved surface portions 9, 11, and 12 and the shape of the curved surface are appropriately determined according to the viscosity of the molten fluid, the affinity with the spinning hole forming member, the spinning speed, and the like. I just need. FIGS. 7 to 9 show a spinneret manufactured by the method according to the second embodiment of the present invention, and show a case where the present invention is applied to a round cross-section yarn nozzle. In the drawing, reference numeral 20 denotes the entire spinneret. As in the first embodiment, the spinning nozzle 20 includes a metal disc member 21 as a nozzle body and a predetermined number of spinning hole forming members 22.
(The second embodiment is also made of a ceramic member). The fixing method of the ceramic member 22 conforms to the first embodiment. A spinning hole 23 is formed in the ceramic member 22, and the spinning hole 23 includes an introduction portion 24, an introduction hole portion 25, a three-dimensional curved surface portion 26 (taper narrowing portion), and a discharge hole portion 27. ing. The discharge hole 27 is formed in a circular cross section, and the introduction portion 24 and the introduction hole 2 are formed.
5. The three-dimensional curved surface portion 26 is also formed in a circular cross section. And the three-dimensional curved surface part 2
6 is such that the shape of the inlet 27a of the discharge hole 27 does not appear so smoothly that the discharge hole 2
7 is connected. Also in such a spinneret for a round cross-section yarn, by forming the inner surface of the hole reaching the discharge hole portion 27 in the three-dimensional curved surface portion 26, particularly at the entrance 27 a of the discharge hole portion 27, a broken line is formed. There are no bent parts, and an extremely smooth flow of the molten fluid is obtained. As a result, there is no site where there is a possibility of stagnation, and there is no site where a large pressure loss occurs, and an extremely smooth flow and a low pressure loss are realized despite being reduced to a small diameter. Further, the ceramic member 22 having the spinning hole 23 is a metal disc member 21.
Separately from the above, the spinneret 20 can be manufactured in a short time and at low cost because it can be manufactured simply, accurately and in large quantities without using electric discharge machining. In this spinneret for spinning round cross-section yarns, the same modifications as shown in FIGS. 5 and 6 are possible, and the shape and length of the three-dimensional curved surface portion may be appropriately set as necessary. Can decide. The melt fluid in the present invention is not particularly limited as long as it can be spun. The die according to the present invention is particularly a synthetic fiber die typified by nylon or polyester, that is, a comparatively complex die. Most suitable for spinnerets for spinning polymers at high pressure. Regenerated fibers typified by rayon and semi-synthetic fibers typified by acetate are often used with a thin base (for example, a simple one in which a plate of about 1 mm is punched with a punch). However, the present invention can be applied to such a fiber when a relatively thick ferrule is used. As described in detail above, when the method for producing a spinneret according to the present invention is used, the portion of the spinning hole reaching the discharge hole portion is formed into a three-dimensional curved surface, so that the stagnant portion is formed. Potentially possible portions can be substantially completely removed, and the pressure loss can be significantly reduced. As a result, the quality of the spun yarn can be improved, and as a result, it is possible to increase the pressure resistance of components upstream of the yarn including the die. In addition, the member having the spinning hole is a separate member from the spinneret main body, the member is formed of a ceramic member and fixed to the spinneret main body, and the spinning hole in the ceramic member is formed at a predetermined outer peripheral portion. By using a pin-shaped mold having a curved surface portion corresponding to a three-dimensional curved surface, a desired hole can be easily formed as described above, and a spinneret can be manufactured in a short processing time at low cost. . The effect of reducing the production cost is more remarkable as the number of holes for spinning increases, and a spinneret having a number of holes of several thousands can achieve a great cost reduction effect.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a spinneret by a method according to a first embodiment of the present invention. FIG. 2 is a partially sectional side view showing the spinneret of FIG. 1; FIG. 3 is an enlarged partial longitudinal sectional view of the spinneret of FIG. 1; FIG. 4 is an enlarged plan view of the spinning hole of FIG. 3; FIG. 5 is a schematic partial longitudinal sectional view showing a spinning hole shape of a spinneret according to a modification of FIG. 1; FIG. 6 is a schematic partial longitudinal sectional view showing a spinning hole shape of a spinneret according to another modification of FIG. 1; FIG. 7 is a plan view of a spinneret according to a second embodiment of the present invention. 8 is an enlarged partial longitudinal sectional view of the spinneret of FIG. 7; FIG. 9 is an enlarged plan view of the spinning hole of FIG. FIG. 10 is a longitudinal sectional view of a spinning hole of a conventional spinneret. FIG. 11 is an enlarged plan view of the spinning hole of FIG. 10; FIG. 12 is a longitudinal sectional view of a spinning hole of another conventional spinneret. FIG. 13 is an enlarged plan view of the spinning hole of FIG. DESCRIPTION OF SYMBOLS 1, 20 Spinneret 2, 21 Metal disc member as spinner body 3 Mounting hole 4, 23 Spinning hole 5, 22 Ceramic member 6 Heat resistant inorganic adhesive 7, 24 Introducing section 8, 25 Inlet hole 9, 11, 12, 26 Three-dimensional curved surface 10, 27 Discharge hole 10a, 27a Inlet of discharge hole

Claims (1)

Claims: 1. A spinning hole provided with an introduction hole through which a molten fluid is introduced, and a discharge hole smaller in diameter than the introduction hole through which the molten fluid is discharged from the introduction hole. In the method for producing a spinneret having a large number of spinning holes, each spinning hole is viewed in the flow direction of the molten fluid, and
At least a portion of the inner surface of the hole that is connected to the inlet of the discharge hole is formed on a three-dimensional curved surface in which the shape line of the inlet of the discharge hole does not substantially appear, and each spinning hole is formed in each ceramic member, The ceramic member is fixed in each of the mounting holes formed in the base body, and the spinning hole in each ceramic member has a pin shape having a curved surface portion corresponding to the three-dimensional curved surface at a predetermined outer peripheral portion. A method for producing a spinneret, characterized in that a forming die is manufactured, a ceramic powder is formed on the pin-shaped forming die into a predetermined member shape, and the shape is formed by firing. 2. The method for producing a spinneret according to claim 1, wherein a cross section of the discharge hole is an irregular cross section. 3. The method for producing a spinneret according to claim 1, wherein a cross section of the discharge hole portion is a round cross section. 4. The spinneret according to claim 1, wherein a heat-resistant inorganic adhesive is filled and solidified between an outer peripheral surface of the ceramic member and an inner peripheral surface of the mounting hole. Method. 5. The spinneret according to claim 1, wherein the three-dimensional curved surface is formed over substantially the entire length of the spinning hole up to the inlet of the discharge hole. Method. 6. The method for producing a spinneret according to claim 1, wherein the cross section of the spinning hole is a deformed cross section over substantially the entire length.