JPH0780178B2 - Strand cooling length adjustment method and apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention discharges a thermoplastic resin in a strand form from a die head having a plurality of nozzles, immerses the discharged strand in cooling water, and conveys the strand with cooling water up and down. The present invention relates to a method for adjusting a cooling length of a strand and an apparatus for adjusting the cooling length of a strand, which is sandwiched between belts and conveyed while being cooled and guided to a cutting machine to form chips.

[0002]

2. Description of the Related Art A strand is a thermoplastic resin discharged from a die head in a string shape. A large number of strands are arranged in a line and continuously cooled and solidified by using an appropriate means. At the same time, it is guided to a cutting machine and cut into chips, which are used as raw materials for synthetic fibers and synthetic resin products. By the way, a typical example of an apparatus that guides a strand discharged from a die head to a cutting machine while cooling and solidifying the strand is provided with a pair of upper and lower belts and is discharged from the die head as disclosed in JP-A-61-189908. The strand is sandwiched between the pair of belts together with the cooling water and cooled and conveyed. By the way, upon cooling the strand, it is necessary to cool the strand to a desired cooling temperature for the following reason.

If cooled too much, the strands become too hard, so that the strands are broken or cracked when they are cut, making the cutting process difficult. If the strand is cooled too much, the internal temperature of the strand will be lowered, so that the moisture adhering to the surface of the strand cannot be evaporated and removed by the heart heat while being conveyed to the cutting machine after the cooling treatment. On the other hand, if the cooling is not enough, the strand is not sufficiently solidified, so when the strand is cut,
The cut surface may be deformed or so-called beard may occur.
Also, the chip shape becomes distorted due to oblique cutting. Therefore, it is necessary to cool the strand so that it becomes a predetermined solidified state, and therefore it is necessary to adjust the cooling length of the strand according to the thermoplastic resin used.

In adjusting the cooling length of such a strand, in the above-mentioned conventional example, a belt having a length corresponding to the cooling length is replaced, or a belt row is connected in multiple stages.
However, in such a conventional example, the cutting machine also needs to be moved, which is troublesome and troublesome. Therefore, in order to solve the above problem, it may be considered to adjust the conveyor speed of the belt. That is, in the case of a strand having a large cooling length, the conveying speed is set low, and in the case of a strand having a small cooling length, the conveying speed is set high. However, if the transport speed is made variable in this way, a new problem occurs that the amount of chips manufactured changes. An object of the present invention is to provide a method for adjusting a cooling length of a strand and an apparatus therefor capable of solving the above problems.

[0005]

In order to solve the above-mentioned problems, the characteristic configuration of the method for adjusting the cooling length of a strand provided by the present invention is that a thermoplastic resin is discharged in a strand form from a die head having a plurality of nozzles. Then, the discharged strands are immersed in cooling water, and the strands accompanied by the cooling water are sandwiched between the upper and lower conveyor belts and conveyed while being cooled to be guided to a cutting machine to form chips. Is formed in a mesh shape with a large number of through holes in advance, and supports a lower conveyor belt and prepares a plurality of blind sealing plates. A sealing plate is inserted and installed side by side from the starting end side of the lower conveyor belt in the lower part of the stretched part, and the length from the start end of the upper stretched part to the final position sealed by the sealing plate is the thermoplastic used. Tree URN URN cooling length of strand in accordance with the types of the points as corresponding.

In addition to the sealing plate, a plurality of water-permeable members capable of discharging cooling water on the upper stretched portion and supporting the upper stretched portion are prepared, and at the bottom of the upper stretched portion, A water-permeable member may be inserted and installed side by side in the remaining part other than the side-by-side position of the sealing plate. The water permeable member may be a plate-shaped body having a plurality of drain holes for discharging cooling water. Further, the cooling water may be sucked by a suction device provided between the sealing plate at the final position of the sealing plates and the water-permeable member adjacent to the final sealing plate.
Further, the characteristic configuration of the strand cooling length adjusting device provided by the present invention is that a thermoplastic resin is discharged in a strand form from a die head having a plurality of nozzles, and the discharged strand is immersed in cooling water and cooled. A strand with water is sandwiched between upper and lower conveyor belts to be conveyed while being cooled and guided to a cutting machine to form chips, wherein the lower conveyor belt is formed in a mesh shape having a large number of through holes,
A plurality of sealing plates, which are blind plates and support the lower conveyor belt, are detachably attached to the lower portion of the upper stretched portion of the lower conveyor belt. In addition to the sealing plate, a water-permeable member capable of discharging cooling water on the upper stretched portion and supporting the upper stretched portion is detachably attached to a lower portion of the upper stretched portion of the lower conveyor belt. It may be attached. The water permeable member may be a plate-shaped body having a plurality of drain holes for discharging cooling water. Further, a suction device for sucking the cooling water may be provided between the sealing plate at the final position of the sealing plates and the water permeable member adjacent to the final sealing plate.

[0007]

According to the present invention, prior to the cooling and conveying of the strands, the sealing plate is inserted and juxtaposed from the starting end side of the lower conveying belt to the lower portion of the upper stretched portion of the lower conveying belt, The length from the starting end to the final position sealed by the sealing plate should be a length that substantially corresponds to the cooling length of the strand. As a result, when the strands discharged from the die head are conveyed while being sandwiched between the upper and lower conveyor belts together with the cooling water, the cooling water is not drained at the belt portion where the sealing plate is provided. Therefore, the strand is cooled in the belt portion. Moreover, since the length of the belt portion is adjusted in advance so as to substantially correspond to the cooling length of the strand according to the type of the thermoplastic resin used, the strand passing through the final sealing plate is desired. It becomes solidified. The cooling water is discharged from the subsequent water permeable member. Therefore, thereafter, the strand is guided to the cutting machine with a desired hardness without being cooled.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. 1 to 5 show a first embodiment of the present invention, FIG. 1 is an overall perspective view of the first embodiment of the present invention, FIG. 2 is an exploded perspective view of essential parts, FIG. 3 is a side view of essential parts, and FIG. 5 and 6 are diagrams for explaining the principle of the present invention. First, referring to FIG. 1, 1 is a die head, which is a batch-type polymerization kettle (not shown).
It is connected to the. The die head 1 has a large number of nozzle holes (not shown), and the molten resin is discharged in a string shape from each nozzle to form the strand row S. 2 in the figure
Although 0 strands are shown, it goes without saying that from 1 to several hundred strands are industrially formed as required, for example, the die head has 50 nozzles in 2 rows each, It is also possible to form 100 strands.

A chute 2 is provided close to the die head 1. The strand row S discharged from the die head 1 drops onto the chute 2 and flows out from a cooling water outflow portion provided on the chute 2. While being cooled by the cooling water, it flows down on the chute 2 together with the cooling water and reaches the inlet of the cooling and conveying section A. Die head 1 and shoot 2
Since a well-known technique is adopted, detailed description is omitted.

The cooling conveyance section A is an endless upper conveyance belt 3
A and 3B and an endless lower conveyance belt 4 are provided. The upper conveyor belt 3A is wound around the rollers 5 and 6, the upper conveyor belt 3B is wound between the rollers 7 and 8, and the lower conveyor belt 4 is wound between the rollers 9 and 10. . Low
The upper conveyor belt 3A is driven and driven in the arrow direction by the rotation of the rollers 5 and 6, and the upper conveyor belt 3B is driven and driven in the arrow direction by the rotation of the rollers 7 and 8 in the arrow direction. The lower conveyor belt 4 is driven to travel in the arrow direction by the rotation of the rollers 9 and 10 in the arrow direction.

By the running of the belts 3A, 3B, and 4 as described above, the strands that have reached the inlet of the cooling / transporting unit A are transported to the outlet of the cooling / transporting unit A together with the cooling water. During this conveyance, the strands are cooled and solidified to have a desired hardness and are guided between the feed rollers 11 and 12. Further, the strands pass between the feed rollers 11 and 12 and are guided to a cutting machine 15 composed of a fixed blade 13 and a rotary cutter 14 and cut into a predetermined length by the cutting machine 15 to form chips 16.

Next, with reference to FIGS. 2 and 3, the structure of the strand cooling mechanism in the cooling and conveying section A will be described in detail. The lower conveyance belt 4 is formed in a mesh shape having a large number of through holes 17 as shown in FIG. A plurality of first support plates 20 that are sealing plates and a plurality of second support plates 21 that are water-permeable members are provided below the upper stretched portion 4A of the lower conveyor belt 4 from the start side of the belt. These supporting plates 2 are arranged side by side in this order over the terminal side.
The upper stretched portion 4A is horizontally supported by 0 and 21. Therefore, when the strand passes over the upper stretched portion 4A, the upper stretched portion 4A is not bent, so that the strand is conveyed in a straight state without waviness.

Further, the first and second support plates 20 and 21
Is supported by a support member (not shown) and is detachable. Therefore, by appropriately attaching and detaching the first and second support plates 20 and 21, the first support plate 20 and the second support plate 21 can be arranged side by side in a desired arrangement state. In the present embodiment, the first support plate 20
The second support plate 21 and the second support plate 21 have the same size, and a plurality of them are prepared in advance. The first support plate 20 is shown in FIG.
As shown in FIG. 5, it is a so-called blind plate in which no drainage holes are formed, and a large number of drainage holes 22 for discharging the cooling water are formed in the second support plate 21. Therefore, in the upper stretched portion 4A of the lower conveyance belt 4, the through hole 17 is formed in the first support plate 20 in the region where the first support plate 20 is arranged.
Since it is sealed by the support plate 20, the cooling water is not discharged, and the cooling state of the strand by the cooling water is maintained. On the other hand, in the upper stretched portion 4A of the lower conveyor belt 4,
In the region where the second support plate 21 is arranged, the cooling water is discharged through the through holes 17 and the drain holes 22, so the strands are not cooled.

In cooling the strand, it is necessary to adjust the cooling temperature of the strand according to the thermoplastic resin because it is necessary to adjust the cooling temperature of the strand to the thermoplastic resin used in order to improve the quality of the chip. Occurs. In such a case, in the present invention, the desired cooling length can be adjusted by changing the arrangement state of the first and second support plates 20 and 21 in advance before the cooling and conveying of the strand. For example, assuming that the cooling length M (see FIG. 4) of the thermoplastic resin used in this example is three times the width length m (see FIG. 4) of the first support plate 20, the first support plate 20.
By arranging three in parallel, the cooling length M can be obtained. Therefore, in the example shown in FIGS. 1 and 2, as shown in FIG.
Support plate 20 and two second support plates 21 are arranged side by side.

When the cooling length M of the thermoplastic resin used is smaller than that in FIG. 4, for example, the cooling length M is the first support plate 20.
When the width m is twice the width m, the cooling length M of the thermoplastic resin used can be obtained by arranging two first support plates 20 side by side. Therefore, as shown in FIG.
From the start end side to the end side of the two first support plates 20
And the three second support plates 21 are arranged side by side. Thus, the first support plate 20 and the second support plate 21
In advance, a simple operation of changing the arrangement state of the first and second support plates 17 and 18 prior to the cooling and conveying of the strands can be performed to obtain a cooling length according to the thermoplastic resin to be used. Obtainable.

Incidentally, for reference, in this embodiment,
Although the second support plate 21 is used as the water permeable member, a support roller may be used as the water permeable member. That is, the support rollers may be arranged below the upper stretched portion 4A of the lower conveyance belt 4 with a space therebetween to discharge the cooling water. However, when the support roller is used in this way, the support roller must be moved when the cooling length is adjusted, and the operation is extremely troublesome. With respect to this point, in this embodiment, it suffices that the support plate be removed and replaced, and the operability is remarkably excellent.

FIG. 6 is a perspective view showing a simplified structure of a main part of the second embodiment of the present invention. In the second embodiment, the suction device 30 is provided between the final first support plate 20 and the first second support plate 21 adjacent thereto. As a result, the amount of cooling water discharged from the drain holes of the second support plate 21 can be reduced, so that the drainage efficiency of the cooling water can be improved, and the cooling and solidification state of the strands can be further highly accurate. Can be realized. In the first and second embodiments, the first support plate 20 and the second support plate 21 have the same shape, but if a large number of different widths are prepared respectively, Further, it becomes possible to adjust the cooling length in multiple stages. Further, although the first supporting plate 20 and the second supporting plate 21 are used in the first and second embodiments, the lower conveying belt 4 has such a hardness that the lower conveying belt 4 does not bend when passing the strand. If so, the second support plate 21 may be omitted. Also in this case, the cooling length of the strand can be made variable and the strand can be conveyed in a straight state.

[0018]

As described above, according to the present invention, in the case where the strands are transported by the vertical transport belt system for a cooling length and the belt length is constant, the cooling length can be adjusted by a simple operation. It can be realized with a simple structure. Therefore, the cooling length according to the thermoplastic resin used can be obtained, and the subsequent processing such as cutting of the strand can be smoothly performed.

[Brief description of drawings]

FIG. 1 is an overall perspective view of a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of a main part of the first embodiment of the present invention.

FIG. 3 is a side view of a main part of the first embodiment of the present invention.

FIG. 4 is a diagram showing an arrangement state of first and second support plates according to the first embodiment of the present invention.

FIG. 5 is a diagram showing an arrangement state of first and second support plates according to the first embodiment of the present invention.

FIG. 6 is a perspective view showing a simplified configuration of a main part of a second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Die head, 3A, 3B ... Upper carrying belt, 4 ... Lower carrying belt, 4A ... Upper carrying part of lower carrying belt, 15 ... Cutting machine, 16 ... Chip, 17 ... Through hole, 20 ... 1st support plate (Sealing plate), 21 ... Second support plate (water-permeable member), 22 ...
Drainage holes, A ... Cooling conveyance section, M ... Cooling length, m ... Width of first support plate 20, S ... Strand row.

Claims (8)

[Claims] 1. A thermoplastic resin is discharged in a strand form from a die head having a plurality of nozzles, the discharged strand is immersed in cooling water, and the strand accompanied by the cooling water is sandwiched between upper and lower conveyor belts. In the case of conveying while cooling and guiding to a cutting machine to form chips, the lower conveyor belt is previously formed in a mesh shape having a large number of through holes, and supports the lower conveyor belt and is a blind plate. Prepare a plurality of sealing plates, and insert the sealing plates from the starting end side of the lower conveyor belt side by side under the upper portion of the lower conveyor belt before the strands are cooled and conveyed. To the final position sealed by the sealing plate, the cooling length adjusting method of the strand, characterized in that it corresponds to the cooling length of the strand according to the type of thermoplastic resin used 2. In addition to the sealing plate, a plurality of water-permeable members capable of discharging cooling water on the upper stretched portion and supporting the upper stretched portion are prepared, and are provided under the upper stretched portion. The method for adjusting the cooling length of a strand according to claim 1, wherein a water-permeable member is inserted and arranged in parallel in the remaining portion other than the juxtaposed portion of the sealing plate. 3. The method for adjusting a cooling length of a strand according to claim 2, wherein the water permeable member is a plate-shaped body having a plurality of drain holes for discharging cooling water. 4. A sealing plate in a final position among the sealing plates,
The cooling water is sucked by a suction device provided between the final sealing plate and a water permeable member adjacent to the sealing plate.
Alternatively, the method for adjusting the cooling length of the strand according to item 3. 5. A thermoplastic resin is discharged in a strand form from a die head having a plurality of nozzles, the discharged strand is immersed in cooling water, and the strand accompanied by the cooling water is sandwiched between upper and lower conveyor belts. In what is conveyed while cooling and is guided to a cutting machine to form chips, the lower conveyor belt is formed in a mesh shape having a large number of through holes,
A cooling length adjusting device for a strand, characterized in that a plurality of blind sealing plates for supporting the lower conveyor belt are detachably attached to the lower portion of the upper stretched portion of the lower conveyor belt. . 6. In addition to the sealing plate, a water-permeable member capable of discharging cooling water on the upper stretched portion and supporting the upper stretched portion is a lower portion of the upper stretched portion of the lower conveyor belt. To
The cooling length adjusting attachment of the strand according to claim 5, which is detachably attached. 7. The cooling length adjusting attachment for a strand according to claim 6, wherein the water permeable member is a plate-like member having a plurality of drain holes for discharging cooling water. 8. A sealing plate in a final position among the sealing plates,
The strand cooling length adjusting device according to claim 6 or 7, wherein a suction device for sucking cooling water is provided between the final sealing plate and a water-permeable member adjacent thereto.