JPS62257412A - Device for producing thin yarn of synthetic resin in extrusion molding machine - Google Patents

Abstract

PURPOSE:To obtain thin yarn (monofilament) having desired thickness without requiring second processing treatment, by inserting a specific pipe having a small diameter into a hole of a die plate. CONSTITUTION:An engaging hole 9 wherein a step part hole 9a having a large diameter is communicated with an inserting hole 9b having a small diameter is bored through a die plate 4 for extrusion molding and a pipe 10 having a small diameter is inserted into the engaging hole. Optionally the pipe 10 fixed to the interior of the hole 9 with a ceramic adhesive. A pipe having a small diameter provided with a part 10c having a small diameter thinned by drawing the other end of a guide pipe 10b having an open flare 10a is used as the pipe 10 having a small diameter.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention relates to a die or T-die mold device in an extrusion molding machine for producing fine yarn, and in particular to a die or T-die mold device for producing fine yarn using an extrusion molding machine. The present invention relates to an apparatus configuration that can be obtained directly by molding without requiring secondary processing such as.

``Prior art'' In the early days, the use of this type of monofilament fine thread was limited to fishing lines, nets, brush bristles, etc., but now it is used in industries such as robes, fishing nets, industrial textiles, furniture textiles, etc. It is used as a material for a variety of purposes.

Then, this kind of fine yarn is produced by installing a die plate with an extrusion port consisting of 20 to 100 small holes at the tip of the extrusion molding machine, cooling the yarn extruded from there, and drawing it. Adjust the thickness and wind each one onto each bobbin.

Therefore, according to this type of conventional manufacturing method, the thickness of the yarn during extrusion may be about 5 to 40 times thicker than the final yarn thickness adjusted by the drawing. , were relatively easy to manufacture.

Incidentally, depending on the use of this type of product, it may be advantageous to mold the thin thread simultaneously with extrusion.

However, the limitation of this simultaneous molding method is that it does not use the drawing process of the monofilament manufacturing method, so when considering the expansion of the molded yarn due to the release of pressure during extrusion molding, the diameter of the molded yarn is smaller than that of the molded yarn. A die plate with an extrusion port must be prepared, and therefore, when the thickness of the thread in the product shape becomes thinner, it is extremely difficult to manufacture a mold for the extrusion port. That is, the die or T-die mold used in an extrusion molding machine usually requires drilling a large number of extrusion holes in a plate made of iron, stainless steel, or special steel with a wall thickness of 3031 JI to 15 JI. Therefore, it is extremely difficult to form a small diameter straight hole through the wall thickness. For this reason, in conventional devices, a method has been adopted in which a large-diameter inner hole or a funnel-shaped inner hole is drilled in the plate, and a small-diameter outer hole is bored in the center of the hole by sputtering.

``Problems to be Solved by the Invention'' However, according to the above-mentioned mold processing means, since the hole volume of the large diameter portion of the extrusion hole in the die plate is large, the resin whose molding temperature is kept at a high temperature is In some cases, internal convection may occur without being extruded uniformly in the part, resulting in a part of the resin remaining in the part for a long time and continuing to be heated. Then, thermal decomposition occurs in this retained resin, and as a result, the molded product may have different properties from the resin's original properties. Furthermore, once the decomposition begins in that part, a chain reaction occurs, and all subsequent molded products that come out of the extrusion port in that part will be of a decomposed nature. Moreover, this decomposition reaction cannot be stopped even if the resin molding temperature is lowered to the lowest moldable temperature. Therefore, the die that has undergone such thermal decomposition must be disassembled and cleaned after once stopping operation.
This requires a lot of work and time. That is,
When using vinyl chloride resin, the above thermal decomposition is usually done at a molding temperature of 150°C to 190°C, with the decomposition temperature being 190°C or higher, but depending on the molding conditions, the temperature range is very fluid. If the temperature exceeds ℃, thermal decomposition becomes noticeable.

Similarly, in the case of vinylidene chloride resin, thermal decomposition begins at 180°C and becomes noticeable in the 190°C range.

Similarly, when using chlorinated polypropylene resin, it is 18
Thermal decomposition occurs at temperatures between 0°C and 190°C.

When vinyl acetate resin is used, thermal decomposition occurs at 200°C.

As described above, since the processing and molding temperature and the thermal decomposition temperature are close to each other, it is extremely difficult to control and manage the molding temperature, and people who live here are accustomed to the occurrence of the decomposition reaction.

As a solution to this problem, it is essential to improve the flow of the resin within the die, and it is necessary to prevent the resin from stagnation within the die as much as possible.

Furthermore, according to the conventional die construction means, the plate surface has a large diameter inner hole or a funnel-shaped inner hole, and the hole spacing necessary to maintain the plate strength is maintained.
Since these nozzles are arranged, it is not possible to achieve a high nozzle arrangement density.

Under such circumstances, the present invention was made for the purpose of developing a practical device that enables simultaneous molding of synthetic resin filaments by extrusion molding means.

"Means to Solve the Problem" In order to achieve this objective, the present invention uses a die and a T-die in an extrusion molding machine by stretching the tip of an open and flared metal tube to form a small diameter tube (with an inner diameter of 1 mm). Attack to 0.
1 m), and the small diameter tube was directly press-fitted into a stepped fitting hole drilled on the die surface by drilling or the like.

"Function" According to the above means of the present invention, the nozzle for forming the fine thread is constituted by a small diameter tube separate from the die plate, and furthermore,
Since the reading tube is a straight small-diameter tube except for the flared part at the inlet, the resin that reaches the die plate by the pressurizing operation of the molding machine is extruded from the nozzle in the die and is directly molded into a small-diameter monofilament thread. Ru. At this time, since the nozzle is composed of a substantially straight hole that passes through the die plate, the inner opening of the plate (
Resin suppression between the resin injection side (resin injection side) and the outer port (resin extrusion side) acts evenly to uniformly extrude the resin that has reached the core, thereby preventing resin retention at the core.

Therefore, it is possible to prevent the resin from being heated for a long time in the die portion, and it is possible to prevent the thermal decomposition reaction of the resin in the core portion.

Moreover, this straight nozzle can be formed into a desired pore (with a diameter of 1 mm or less) by forming a small diameter tube in the shape of an injection needle by drawing a metal tube. As a hole for inserting the small diameter tube into the die plate, a hole that is at least as large as the hole diameter of the reading tube and the wall thickness can be easily drilled by drilling, so as a result, It is possible to machine small diameter straight holes in the die plate.

According to the nozzle configuration according to the means of the present invention, the diameter of the large diameter side of the stepped fitting locking hole drilled in the die surface is smaller than that of the conventional one. This is effective in increasing the hole installation density.

Preferred embodiments of the present invention will now be described with reference to the accompanying drawings.

``Example'' Figure 1 is a partially longitudinal side view showing an example of a thin yarn manufacturing apparatus comprising the apparatus of the present invention, in which compound long-fat material is directed from a hopper 1 to a head part 3 while being pressurized by a screw auger 2. It is fed out and guided to a die 4 attached to the head part 3, and a large number of nozzles 5, 5, and 5 are installed on the die 4.
. . . The molded yarn 6° 6 . . . is extruded and passed through the cooling water tank 7 and wound up. Others, 8
indicates a heating heater.

By the way, the molded yarn extruded from the nozzle 5 under pressure is
Due to the pressurizing force at this time, the nozzle 5 is formed in a shape that is thicker than the diameter of the nozzle 5. For example, a monofilament yarn extruded from a nozzle 5 with a diameter of 1 m is formed to have an outer diameter of 1.1 mm to 1.2 mm. Therefore, when it is desired to mold a thin thread with an outer diameter of 0.5 m, the nozzle 5 must have an inner diameter of at least 0.4 js to 0.35 m.

FIG. 2 shows a die plate for the nozzle configuration in the apparatus of the present invention, in which the die 4 has a large-diameter step hole 9a (for example, 2.121 mm) inside the plate and a small-diameter step hole 9a (for example, 1.2 mm wide) connected to this step hole 9a. A guide portion 10b (for example, an outer diameter of 2.1131 ml and an inner diameter of 1.692 mm) is opened and has a flared portion 10a.
8) is formed at one end, and the other end is stretched to form a small diameter hole 10c in the shape of a syringe needle (for example, an outer diameter of 0°85mm to 1mm).
．． A small diameter tube 10 machined to a diameter of 0.05 m and an inner diameter of 0.43 to 0.70 mb) is press-fitted. Note that this small diameter tube 10
Although it is preferable that the shape of the inlet edge of the engagement hole 9 and the shape of the open flare portion 10a match, for example, some gap may occur between the insertion of the engagement hole 9 and the small diameter tube 10. Even in such a case, subsequent resin leakage from the flared portion 10a etc. is naturally prevented. However, if necessary, these gaps may be filled with ceramic adhesive 11 to attach the small diameter tube 10 to the hole 9.
It may be fixed integrally inside.

3 and 4 are longitudinal cross-sectional views showing embodiments of the small diameter tube 10, respectively, and the one in FIG. Similarly, in the case shown in FIG. 4, approximately 2/3 of the total length is
It is formed into C. Then, the large diameter opening flare portion 1
A funnel opening with an inclination angle (approach angle) of 30° is formed between 0a and the small diameter hole 10C.

According to the embodiment having such a configuration, the thin tube (inner diameter I
A small diameter tube 10 (approximately 0.1 m to 0.1 m) is used by press-fitting it into the retaining hole 9 of the die plate, but in case of unforeseen circumstances, it may be molded into the set nozzles 5, 5... Since the thermal decomposition reaction of the resin has occurred, the forming operation using the die can be continued. It is also possible to use it interchangeably with a 1° narrow diameter tube of a different diameter.

Furthermore, since the lengths of the small diameter holes 10b are different as shown in FIGS. 3 and 4, the extrusion speed of the molded yarn from the nozzle 5 is made slower as the length becomes longer during extrusion molding under a predetermined pressure. Therefore, it is effective to selectively use these small diameter tubes 10 depending on the purpose of use of the resin material or molded thread. Since the nozzle placed on the T-die is formed through a straight hole of approximately the same shape across the inner and outer surfaces of the die plate, it is possible to prevent the molding resin from staying inside the nozzle and prevent the thermal decomposition reaction of the resin at the core, resulting in a small diameter mold. It is now possible to stably mold monofilament thread, and what's more, the tip of the open flared metal tube that makes up this small diameter nozzle is stretched! It is constructed into a small diameter tube (inner diameter length 1 meter to Q, 1 meter) by processing, and the small diameter tube is used by being directly pressurized into a stepped fitting locking hole drilled on the die surface by drilling etc. In addition to homogeneously mass-producing the small-diameter straight structure intended as this nozzle, by configuring the locking hole to the plate in a fixed shape, the locking hole can be filled with small-diameter tubes with different nozzle diameters. The die plate can be changed in many ways, such as being able to be used by replacing it as appropriate.Moreover, since the retaining holes drilled in the die plate have a relatively small diameter, the nozzle installation density on the die surface can be increased. The present singing device is extremely practical as it allows for efficient molding work.

[Brief explanation of drawings]

FIG. 1 is a partially vertical side view showing an embodiment of a manufacturing apparatus using the apparatus of the present invention, FIG. 2 is a longitudinal cross-sectional view of a die showing the configuration of the main parts of the apparatus of the present invention, FIG. 4 is a longitudinal cross-sectional view showing an embodiment of a small diameter tube in the device of the present invention. 4... Die 5... Nozzle 6... Molding thread 9... Engaging hole 9a... Step hole 9b... ...Insertion hole 10...Small diameter tube 10a...
...Opening flare part 10b...Guide part
11... Ceramic adhesive. 10C・・・Small hole patent applicant Lithrone Co., Ltd. 1, 2, 3, 4, 2

Claims (4)

[Claims] (1) The die and T die in the extrusion molding machine are made into small diameter tubes by stretching the tip of the open flared metal tube.
1. An extrusion molding machine characterized by having an inner diameter length of 1 mm to 0.1 mm), and having the small diameter tube directly press-fitted into a stepped fitting locking hole drilled on a die surface by drilling or the like. Equipment for manufacturing fine synthetic resin threads. (2) An apparatus for producing thin synthetic resin thread in an extrusion molding machine according to claim (1), wherein the lengths of the small diameter tube portions are different. (3) An apparatus for producing thin synthetic resin thread in an extrusion molding machine according to claim (1), wherein the small diameter tube is removably fitted into the locking hole. (4) An apparatus for producing thin synthetic resin thread in an extrusion molding machine according to claim (1), wherein the small diameter tube is integrally fitted into the locking hole with the interposition of a ceramic adhesive.