JP2001277337A - Method for manufacturing eave trough, cooling mold and apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an eave trough, capable of cooling the hollow solid body part of the resin extrudate extruded from a kneading extruder at the same cooling speed as the solid surface part of the extrudate and sliding the extrudate through a cooling mold without clogging the mold to mold the same, the cooling mold and an apparatus. SOLUTION: In the method for manufacturing the eave trough, the cooling mold and the apparatus 20, the resin extrudate 31 becoming the eave trough 31A, which is made of a thermoplastic resin and of which the cross section is constituted of the solid surface part 32 and the hollow body part 36, is extruded from the kneading extruder 21 and, in a cooling part consisting of a series of a first cooling mold 23, a second cooling mold 24 and a cooling water tank 29, the outer peripheral surface 33 of the resin extrudate 31 and the outer surface 33 of the hollow body part 36 are sucked under vacuum so as to be brought into close contact with the surfaces of the cooling molds to be cooled. In this case, a cooling mold constituted so as to cool at least a part of the hollow body part 36 by a liquid prior to the suction under vacuum is provided as the second cooling mold 24 in the cooling part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a rain gutter extruded from a thermoplastic resin, a cooling mold and an apparatus therefor.

[0002]

2. Description of the Related Art Conventionally, rain gutters are widely used because they are formed of hard vinyl chloride resin, which is one of thermoplastic resins. There is a possibility that the appearance may be deteriorated due to thermal deformation or brittleness and breakage in winter. For this reason, rain gutters using an olefin-based resin, which is one of thermoplastic resins, having high heat resistance and thermal stability are being adopted.

However, since this olefin resin is crystalline, the molding shrinkage during molding is large, and molding is difficult.

Therefore, when manufacturing a rain gutter of an olefin resin using the kneading extruder 1 as shown in FIG. 6 which is widely used, the resin extruded body 31 extruded from the kneading extruder 1 must be removed. If the cooling balance is not achieved, the amount of shrinkage will vary, resulting in deformation and uneven wall thickness, making it impossible to maintain the molding accuracy of the rain gutter 31A.

In order to cool the resin extruded body 31, a series of cooling of the first cooling mold 3, the second cooling mold 4, and the cooling water tank 5 is performed. The area is cooled to form the rain gutter 31A.

Then, in the series of cooling units 3, 4, and 5, a second cooling mold 4 that has the widest cooling temperature range.
Is a solid surface portion 32 of the resin extruded body 31 as shown in FIG.
A plurality of negative pressure portions Av are provided along the outer peripheral surface 33 of the resin extruded body, vacuum suction is performed, and the outer peripheral surface 33 of the resin extruded body 31 is cooled while being in close contact with the surface of the mold 4 so that the shape of the outer peripheral surface 33 can be regulated. I have to. Further, the cooling water Wa flows into the inner peripheral surface 34 to form a water film Wf, and the inner peripheral surface 34 of the resin extruded body 31 is formed.
So that it can be cooled.

As shown in FIG. 8, the cooling of the hollow body portion 36 by the second cooling mold 4 is performed on the outer peripheral surface 3 of the resin extruded body 31.
3 and a plurality of negative pressure portions Av are provided along both surfaces of the outer surface 37 of the hollow body portion 36, and the outer peripheral surface 33 of the resin extruded body 31 and the hollow body are sucked from the negative pressure portion Av by vacuum suction. The outer surface 37 of the portion 36 is brought into close contact with the surface of the mold 4 so that shape control and cooling can be performed.

[0008]

However, when the crystalline olefin resin shown in FIG. 5 is extruded using the second cooling mold 4 and the shape is regulated and cooled by vacuum suction, Table 4 is obtained. As shown in the conventional example, although the molding shrinkage of the resin extruded body 31 can be well controlled to +0.25 to -3%, the resin extruded body 31 often has a negative pressure portion Av of the second cooling mold 4. It was adsorbed on, and stopped working and jammed. On average, this trouble occurred seven times a day (see Table 4), resulting in a problem of reducing productivity.

Therefore, according to the present invention, the hollow body portion of the resin extruded body extruded from the kneading extruder is cooled in the same manner as the cooling speed of the solid surface portion, and slides without clogging in the cooling mold. It is an object of the present invention to provide a method for manufacturing a rain gutter that can be formed, a cooling mold and a device.

[0010]

Means for Solving the Problems To achieve the above object, an invention according to claim 1 is a method for manufacturing a rain gutter, comprising: a cross section comprising a solid surface portion and a hollow body portion; In a cooling mold in which a resin extruded body serving as a rain gutter is continuously formed while being extruded, vacuum suction is performed so that the outer peripheral surface shape of the resin extruded body and the outer surface of the hollow body part are in close contact with the cooling mold. And at least a part of the hollow body is liquid-cooled prior to the vacuum suction.

In such a case, the outer surface of the hollow body is liquid-cooled prior to vacuum suction.
By cooling the liquid having a large heat capacity, the cooling speed of the outer surface of the hollow body having a large heat storage amount can be made equal to that of the solid surface of the resin extruded body.

Here, the term "thermoplastic resin" is a general term for thermoplastic resins, and is not particularly limited as long as extrusion molding is possible. (PP), polyethylene (PE), polyethylene terephthalate (PET) and polyamide (P)
A) and polybutylene terephthalate (PBT).

According to a second aspect of the present invention, in the method for manufacturing a rain gutter according to the first aspect, the inner peripheral surface of the resin extruded body is pressed by the pressurized liquid refrigerant in the solid surface portion. Further, it is characterized in that the outer peripheral surface side is cooled while being brought into close contact with the surface of the cooling mold by vacuum suction.

In such a resin extruder, the outer peripheral surface of the resin extruded body is vacuum-sucked, and the inner peripheral surface is pressed by a liquid refrigerant. , The shape is more strongly regulated.

According to a third aspect of the present invention, in the cooling mold, in the hollow body portion of the resin extruded body, a liquid refrigerant can be filled between a front half of an outer surface thereof and a surface of the mold, and It is characterized in that the latter half of the outer surface can be brought into close contact with the surface of the mold by vacuum suction.

In such a device, the first half of the cooling mold is liquid-cooled, and the second half can be vacuum-sucked, so that the hollow body which is hardly cooled by heat storage is formed at the entrance of the cooling mold. In the above, it is rapidly cooled by the liquid refrigerant and easily enters the cooling mold, and is vacuum-sucked when cooled to an appropriate state in the filled mold, so that the outer surface of the hollow body portion is formed of the mold. It can be brought into close contact with the surface.

According to a fourth aspect of the present invention, in the apparatus for manufacturing a rain gutter, a resin extruded body having a cross section constituted by a solid surface portion and a hollow body portion and serving as a rain gutter made of a thermoplastic resin is formed by a kneading extruder. In an extruded and subsequent series of the first cooling mold, the second cooling mold and the cooling part of the cooling water tank, the outer peripheral surface shape of the resin extruded body and the outer surface of the hollow body part are formed on the surface of the cooling mold. A vacuum mold is cooled by vacuum suction so as to bring them into close contact with each other, and a cooling mold in which at least a part of the hollow body is liquid-cooled prior to the vacuum suction is placed in a second one of the cooling units.
It is characterized by being provided as a cooling mold.

In this case, the hollow body having a large heat storage amount is cooled at the entrance of the second cooling mold by a liquid refrigerant having a large cooling capacity, and the passage is easy because no vacuum suction is performed at the entrance. Then, since the vacuum is sucked after being appropriately cooled, the apparatus for manufacturing a rain gutter provided with the second cooling mold capable of suppressing the shape deformation of the hollow body is provided.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for manufacturing a rain gutter according to the present invention will be described below with reference to FIGS.

In FIG. 1, reference numeral 20 denotes, as an example, a resin extruder for melting and extruding a crystalline thermoplastic resin. The resin extruder is attached to the tip of the kneading device 21 and has a substantially U-shaped cross section as shown in FIG. Then, an extrusion die 22 for extruding a resin extruded body 31 composed of a solid surface portion 32 and a hollow body portion 36, and a refrigerant is blown toward the resin extruded body 31 extruded from the extrusion die 22 to maintain the shape. Possible thickening temperature (for PP: 1
(50-180 ° C.), the first cooling mold 23 which passes while cooling the resin, and the solid surface portion 32 of the resin extruded body 31 are cooled by vacuum suction of the outer peripheral surface 33, and the inner peripheral surface 34 holds the liquid refrigerant Wa. The liquid is cooled by press-fitting.
Is filled with a second cooling mold 24 configured to cool the outer surface 37 from a liquid cooling to a cooling by vacuum suction to a crystallization temperature range in two stages that change in the middle, and water or the like as a liquid refrigerant Wa. A series of cooling units with a cooling water tank 29 for causing the resin extruded body 31 to pass through the resin extruded body 31 and cool the solidified temperature or below are arranged in this order.

Each of the cooling units 22 and 2
A take-up machine 201 is installed at the rear of 3, 24, 29, and the cooled resin extruded body 31 is nipped and taken up by a rotating caterpillar 202 mounted on the take-up machine 201, and the cutter 203 is cut to a predetermined length. , And the rain gutter 30A is formed.

A second cooling mold 2 which is a cooling mold shown in FIG.
In the cross-sectional view of FIG.
A surface negative pressure portion 25 and a liquid cooling portion 26 are provided along the outer peripheral surface 33 and the inner peripheral surface 34 (see FIG. 5), respectively.

The surface negative pressure portion 25 has a plurality of surface negative pressure portions 25 in which a metal piece or the like having an air hole is buried flush with a mold surface portion 24A through which the resin extruded body 31 slides.
Is formed. Therefore, the outer peripheral surface 33 of the resin extruded body 31 is vacuum-sucked to the mold surface portion 24A from the surface negative pressure portion 25 via a vacuum pipe, closely contacted with the mold surface portion 24A, and cooled.

On the inner peripheral surface 34 of the resin extruded body 31,
A water cooling unit 26 is provided in connection with the water supply pipe.
From the plurality of holes toward the inner peripheral surface 34 of the solid surface portion 32, and the mold surface portion 24A and the inner peripheral surface 34 of the solid surface portion 32 are pressed.
And a water film 28 is formed between them.

Therefore, the solid surface portion 3 of the resin extruded body 31
2, the shape of the outer peripheral surface 33 can be regulated by vacuum suction of the solid surface negative pressure portion 25 of the mold surface portion 24A, and at the same time, it is cooled by the close mold surface portion 24A.

The inner peripheral surface 34 of the solid surface portion 32 is pressed by the water film 28 formed by press-fitting from the liquid cooling portion 26 and is also cooled by the water film 28 at the same time.
Is cooled while regulating the shape from both the outer peripheral surface 33 and the inner peripheral surface 34, and can pass through the second cooling mold 24 while sliding.

The cooling temperature in the second cooling mold 24 is as follows:
Cool to a temperature 5-20 ° C. above the crystallization temperature. That is, usually, 110 to 1 in polypropylene (PP).
40 ° C, 1 for polyethylene terephthalate (PET)
It is cooled to about 90 to 220 ° C.

In the sectional view of the second cooling mold 24 shown in FIG. 3, the solid surface 32 of the resin extruded body 31 is provided with a plurality of surface negative pressure portions 25 along the outer peripheral surface 33 to form a vacuum. Suction is possible as in the case of FIG.

The hollow body portion 36 of the resin extruded body 31
Is provided along the extrusion direction of the resin extruded body 31 on the outer surface 37 thereof, in the first half L1 from the inlet side, a liquid cooling section 26 connected to a water absorption pipe. Of the mold hollow body 24B and the outer surface 37 of the hollow body 36 to form a water film 28 so that liquid cooling can be performed.

In the second half L2 following the first half L1, a plurality of hollow body negative pressure portions 27 are provided, and the resin extruded body 31 cooled to a predetermined temperature in the first half L1 is provided.
Can be closely attached to the surface of the mold hollow body portion 24B by vacuum suction.

As described above, the outer surface 3 of the hollow body 36
Reference numeral 7 denotes the extrusion length of the resin extruded body 31 of the second cooling mold 24, in which liquid cooling is changed in two stages so that cooling is performed while suctioning the liquid from the middle.

FIG. 4 shows the cooling structure of the second cooling mold 24 in a cross section which intersects with the extrusion direction of the resin extruded body 31. Mold surface portion 24A for forming outer peripheral surface 33 of body 31
And a mold hollow body portion 24B for forming the inner peripheral surface 34 of the resin extruded body 31. Both mold surfaces 24A,
A die slit 24C for extruding the resin extruded body 31 is formed so as to be surrounded by 24B. The surface negative pressure portion 25 for regulating the outer peripheral surface shape of the resin extruded body 31 and the inner peripheral surface 34 (including the outer surface 37 of the hollow body portion 36) of the resin extruded body 31 are directly formed along the die slit 24C. A liquid cooling section 26 for liquid cooling is formed.

In the surface negative pressure portion 25, negative pressure sizings Aa, Ab and Ac are provided on the respective surfaces of the mold surface portion 24A along the outer peripheral surface 33 of the resin extruded body 31, and via a pipe. To allow vacuum suction.

The liquid cooling section 26 includes the resin extruded body 3
The cooling water Wd, We, Wfa, Wg is provided directly on each surface of the mold hollow body 24B along the inner peripheral surface 34 of the mold 1, and the liquid refrigerant Wa is press-fitted through piping.

The part of the liquid cooling part 26 into which the direct cooling water Wfa is injected is the first half of the length of the second cooling mold, and the latter part is switched to the negative pressure sizing Afb which is the hollow negative pressure part 27. Vacuum suction is performed, and die slit 2
The outer surface 37 of the hollow body 36 sliding on 4C is brought into close contact with the mold hollow body 24B so that the shape can be regulated.

Accordingly, since the hollow body portion 36 of the resin extruded molded body 31 which is difficult to cool by storing heat can be cooled with a liquid having a large heat capacity prior to vacuum suction, the same cooling as the solid surface portion 32 is achieved. The speed can be increased, and the hollow body 36 can be cooled while sliding without contacting the surface of the die slit 24C.

In FIG. 5, 31 is a sectional view of a resin extruded body 31 extruded as a rain gutter 31A, 33 is an outer peripheral surface thereof, and 34 is an inner peripheral surface thereof. A hollow body 36 having a substantially rectangular cross section is provided.

The portion of the hollow body 36 that protrudes into the inside of the inner peripheral surface 34 in an angular shape is referred to as an outer surface 37 of the hollow body 36.

[0039]

EXAMPLE 1 A gutter having a sectional shape shown in FIG. 5 was formed using the apparatus shown in FIGS. 1, 2, 3 and 4. The molding conditions at this time are shown in Table 1.

● Material for forming rain gutter ・ Crystalline thermoplastic resin: PP resin (manufactured by Mitsubishi Chemical Corporation, Polypropylene EA9) ・ Thickness of resin extruded body: about 1.5 mm ● Molding conditions:

[0041]

[Table 1]

Molding results (see Table 4): Molding shrinkage
It was +0.3 to -3% compared to the design dimensions, and there was no molding trouble. It can be judged as good.

(Embodiment 2) FIGS. 1, 2, 3 and 4
The rain gutter having the sectional shape shown in FIG. 5 was formed using the apparatus shown in FIG.
The molding conditions at this time are shown in Table 2.

● Material for forming rain gutter ・ Crystalline thermoplastic resin: PP resin (Polypro EA9 manufactured by Mitsubishi Chemical) ・ Carbon fiber chop (Vesfight HT manufactured by Toho Rayon)
B-C6-SR) was mixed in the PP resin at 5 vol%.

Thickness of resin extruded body: about 1.5 mm Molding method Kneading extrusion molding method Molding conditions:

[0046]

[Table 2]

● Molding results (see Table 4):
It was +0.5 to -1% compared to the design dimensions, and the number of molding troubles was not found at all. It can be judged as good.

[0048]

2. Description of the Prior Art A rain gutter having a sectional shape shown in FIG. 5 was formed by using the apparatus shown in FIGS. The molding conditions at this time are shown in Table 3.

● Material for forming rain gutter ・ Crystalline thermoplastic resin: PP resin (Polypro EA9 manufactured by Mitsubishi Chemical) ・ Thickness of resin extruded body: about 1.5 mm ● Molding conditions:

[0050]

[Table 3]

Molding results (see Table 4): Molding shrinkage
It was +0.25 to -3% compared to the design dimensions, and it could be determined that the shape was good. However, the number of troubles is seven times a day on average, which lowers the productivity, and thus needs to be improved.

Conclusion Table 4 shows the molding results of Examples 1, 2 and the conventional example.

[0053]

[Table 4]

[0054]

According to the method of manufacturing a rain gutter according to the present invention, the outer surface of the hollow body is liquid-cooled prior to vacuum suction, so that the liquid cooling having a large heat capacity is performed. Thereby, the cooling speed of the outer surface of the hollow body part having a large heat storage amount can be made equal to that of the solid surface part of the resin extruded body.
Therefore, the hollow body portion of the resin extruded body is not adsorbed on the surface of the cooling mold and clogging does not occur, thereby improving productivity.

Further, since the resin extruded body is cooled in a well-balanced manner, the width of the shrinkage ratio becomes narrow and the molding defects such as curving and warping do not occur irrespective of whether the resin material is reinforced or reinforced (Examples 1 and 2). , The commercial value of the gutter has improved.

According to the second aspect of the present invention, the outer peripheral surface of the resin extruded body is suctioned by vacuum, and the inner peripheral surface is pressed by the liquid refrigerant. Can be more strongly adapted to the surface. Therefore, the dimensional accuracy and the surface smoothness are improved, so that the merchantability can be improved.

According to the third aspect of the present invention, the first half of the cooling mold is liquid-cooled, and the second half can be vacuum-suctioned. Since the portion can be rapidly cooled by the liquid refrigerant and can be evacuated when it reaches an appropriate cooling state, the shape of the outer surface of the hollow body can be regulated without clogging in the cooling mold. Therefore, even if the extrusion was performed with insufficient cooling in the first cooling mold, the second cooling mold was cooled at the entrance of the mold to cover molding problems.

According to the fourth aspect of the present invention, the hollow body having a large heat storage amount is cooled at the entrance of the second cooling mold by the liquid refrigerant having a large cooling capacity, and the passage is easy because the entrance does not perform vacuum suction. In addition, since the vacuum is sucked after being appropriately cooled, the shape deformation of the hollow body can be suppressed, and the second cooling mold that improves the productivity and the commercial value is formed in a series of cooling units. A rain gutter manufacturing system was established.

[Brief description of the drawings]

FIG. 1 is a resin extrusion apparatus diagram showing a method for manufacturing a rain gutter according to the present invention.

FIG. 2 is a cross-sectional view of a main part showing a side surface of a mold surface of a second cooling mold of FIG. 1;

FIG. 3 is a sectional view of a main part showing a side surface of a mold hollow body of a second cooling mold of FIG. 1;

FIG. 4 is a cross-sectional view of a main part intersecting the extrusion direction of a second cooling mold of FIG.

FIG. 5 is a sectional view of a main part showing a resin extruded body according to the present invention.

FIG. 6 is a resin extrusion apparatus diagram showing a state of cooling a resin extruded body according to a conventional technique.

FIG. 7 is a cross-sectional view of a main part showing a side surface of a mold surface of the second cooling mold of FIG. 6;

8 is a cross-sectional view of a main part showing a side surface of a mold hollow body of the second cooling mold of FIG. 6;

[Explanation of symbols]

 REFERENCE SIGNS LIST 20 resin extruder 21 kneading extruder 23 first cooling mold 24 second cooling mold 29 cooling water tank 31 resin extruded body 31A rain gutter 32 solid surface part 33 outer peripheral surface 36 hollow body Department

Claims (4)

[Claims] An extruded resin mold having a cross section composed of a solid surface portion and a hollow body portion and serving as a rain gutter made of a thermoplastic resin is formed in a cooling mold that is continuously extruded. And vacuum cooling so that the outer surface of the hollow body portion is in close contact with the cooling mold and cooling, and prior to this vacuum suction, at least a part of the hollow body portion is liquid-cooled. A method for manufacturing a rain gutter, comprising: 2. In the solid surface portion, the inner peripheral surface of the resin extruded body is pressed by pressurized liquid refrigerant, and the outer peripheral surface side is vacuum-sucked so as to be in close contact with the surface of the cooling mold. The method for manufacturing a gutter according to claim 1, wherein the gutter is cooled. 3. The hollow portion of the resin extruded body can be filled with liquid refrigerant between the first half of the outer surface and the surface of the mold, and the second half of the outer surface can be filled with the surface of the mold by vacuum suction. A cooling mold characterized in that it can be brought into close contact with the cooling mold. 4. A resin extruded body having a solid surface section and a hollow body section, which is a rain gutter made of thermoplastic resin, is extruded from a kneading extruder, and is followed by a series of first cooling mold and second cooling mold. In the cooling part of the cooling mold and the cooling water tank, the outer peripheral surface shape of the resin extruded body and the outer surface of the hollow body part are vacuum-suctioned and cooled so that the outer surface of the hollow body part is in close contact with the surface of the cooling mold. An apparatus for manufacturing a rain gutter, comprising a cooling mold in which at least a part of the hollow body is liquid-cooled as a second cooling mold in the cooling section.