JPH09248849A - Sheet rolling method and apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform the rolling of sheet width exceeding the capacity of a single extruder when a plastic material is rolled into a sheet shape by the extruder. SOLUTION: When a plastic material is sent to a calender 16 from an extruder 11 to be rolled into a sheet shape, the plastic material is extruded from a plurality of screw extruders 11 parallelly arranged in the width direction of the rolls of the calender. The plastic material is extruded from the adjacent extruders to be formed into sheets and the side ends of the sheets are mutually fused in the calender 16 to obtain a wide plastic material sheet.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet rolling method and apparatus for rolling a plastic material such as rubber, thermoplastics and thermoplastic elastomers into a sheet having a large width.

[0002]

2. Description of the Related Art Conventionally, in order to produce a wide sheet from a plastic material such as rubber, thermoplastic resin, or thermoplastic elastomer, a plasticized material is placed between calender rolls in which three or four rollers are arranged in parallel. The sheet manufacturing method of uniformly feeding and rolling the entire surface of the roll was common, but in recent years, the discharge port of the screw type extruder is brought close to between calender rolls, and the sheet is directly fed while plasticizing the material. Rolling equipment has been developed and is in widespread use.

This sheet rolling apparatus has a structure as illustrated in FIGS. 5 and 6, and its extruder 1 is used.
Includes a feed unit 2, a screw cylinder 3, and a discharge port 4 of the head unit. The mouthpiece 4 of the head portion is provided with a flat slit-shaped discharge port 5b suitable for pushing out a sheet at the tip of a fishtail type (fishtail-shaped) discharge path 5a. Then, for example, when a ribbon-shaped rubber material as a plastic material is supplied to the extruder from the feed section 2, the rubber material is bitten by the rotating screw 3a in the feed section 2 and accompanying the rotation of the screw 3a. Screw cylinder 3
Sent in the direction of the base 4.

The sheet of plastic material extruded from the discharge port 5b is then sheeted by a calendar 6. This calendar 6 is a first roll 6a which is a heating roll,
The second roll 6b and the third roll 6c which is a cooling roll.
Etc. are arranged in an array, the first roll 6a and the second roll 6a
The sheet that has been caught between the rolls 6b is sequentially seated between the rolls.

In such a sheet rolling apparatus, for example,
Even if a plastic material is supplied by directly opening the discharge port of the extruder 1 having an inner diameter of the screw cylinder 3 of 90 mm between the rolls of the calender 6, there are many materials that cannot be rolled uniformly on the entire roll surface. Using a die 4 having a die discharge passage 5a, a plastic material is extruded from a discharge port 5b at the tip of the die 4 as a sheet having a width of 400 to 500 mm and a thickness of 7 to 10 mm between rolls of a calender 6, and the width of the calender 6 is reduced. A sheet S having a thickness of 600 to 700 mm and an arbitrary thickness is rolled.

However, when a plastic material such as rubber having a high viscosity and poor fluidity is extruded from the discharge port 5b to the calender 6 in the form of a flat sheet, the inner diameter of the screw cylinder 3 in the extruder 1 causes Even if the width of the flat sheet to be extruded is determined and the divergence angle of the fish tail type discharge passage 5a in the discharge mouthpiece 4 at the tip of the extruder 1 is increased, the discharge port exceeds the restriction due to the fluidity of the plastic material, The width of the sheet extruded from 5b cannot be increased. That is, there is a limit to the size of the opening width of the discharge port 5b of the mouthpiece 4 having the fish tail type discharge passage 5a with respect to the diameter of the screw cylinder 3. Further, naturally, the rolling width of the roll of the calender 6 that rolls the material extruded from the discharge port 5b of the extruder 1 is also restricted by the width of the material supplied from the extruder 1. That is, in order to roll a wider sheet with the calendar 6, the extruder 1 having a screw cylinder 3 with a large inner diameter must be equipped. Instead of the fish tail type discharge passage, there is also a means to push the inner tail of the cylinder into a tube with the outer tail and split it into two parts and open it smoothly to form a plate and supply it to the calender. It is extremely difficult to exceed the upper limit width of the tip of the outlet.

As described above, if a wide sheet is to be rolled, the extruder 1 having a large screw cylinder 3 inside diameter is required.
When the inner diameter of the extruder is increased, the whole extruder becomes very large and expensive, and the power for operating the extruder is also increased accordingly, and even if the production capacity is increased, the sheet This will significantly increase the manufacturing cost.

[0008]

DISCLOSURE OF THE INVENTION The technical problem to be solved by the present invention is to feed a plastic material from an extruder to a calender and roll the plastic material into a sheet in a sheet width exceeding the capability of a single extruder. Sheet rolling method and apparatus capable of rolling the sheet in the calender as much as possible compared with the inner diameter of the screw cylinder of the extruder. To do.

Further, the present inventor has found that when the side edges of the plastic material (rubber) extruded from the discharge ports of the two extruders arranged side by side are supplied to the calender so that they are joined to each other. It has been confirmed that the rolled sheets are fused with each other in the vicinity of the joining line and the surfaces have an integrated sheet surface. The present invention is based on such knowledge, and therefore, its specific technical problem is to increase the sheet width to be rolled by a calender and to adjoin the screw cylinder in an extruder without increasing the inner diameter. It is an object of the present invention to provide a sheet rolling method and a sheet rolling method capable of coping with a plurality of screw cylinders each having a small diameter by utilizing the fact that the sheets fuse with each other at their joints.

[0010]

In the sheet rolling method of the present invention for solving the above problems, a plastic material is flattened from an outlet of a die having a fish tail type outlet in a head portion of a screw type extruder. Sent to a calendar, when rolling the plastic material into a sheet in a calendar, the plastic material is extruded from a plurality of screw type extruders arranged side by side in the width direction of the roll in the calendar,
It is characterized in that the side edges of the plastic material sheets extruded from the adjacent extruders are fused with each other in a calender to obtain a plastic material sheet having a large sheet width.

Further, in the sheet rolling apparatus of the present invention, the plastic material is flattened from the outlet of the die having the fish tail type discharge passage in the head part of the screw type extruder and sent to the calender, and the plastic material is fed in the calender. In a sheet rolling apparatus for rolling into a sheet shape, a plurality of the screw type extruders, with a gap such that the side edges of the sheets of the plastic material extruded from the adjacent extruder are mutually joined in the calender, the width of the roll in the calender. It is characterized in that they are arranged side by side. The sheet rolling apparatus, adjusting means for adjusting the intervals of the plurality of extruders,
A means for rotating the screws of a plurality of extruders at a constant speed, or a pressure sensor for detecting the extrusion pressure of the plastic material in the heads of a plurality of extruders is provided, and the extrusion pressure of each extruder is equalized based on its output. The control means may be provided.

In the sheet rolling method and apparatus of the present invention described above, when the plastic material is flattened from the discharge port in the head portion of the extruder and sent to the calender and rolled into a sheet, the plastic material is fed into a plurality of screw types. When extruded from the extruder, the side edges of the sheets of the plastic material extruded from the adjacent extruder are joined to each other along with the rolling in the calender, and the vicinity of the joining line of both the rolled sheets becomes a fusion state with each other, It will present an integrated seating surface. Therefore, without increasing the inner diameter of the screw cylinder in the extruder, it is possible to increase the rolling sheet width in the calender compared to the inner diameter of the screw cylinder, and the device itself is inexpensive and the running cost is low. With a screw cylinder,
It is possible to obtain a sheet of a plastic material having a large sheet width.

[0013]

1 to 4 show an embodiment of a sheet rolling apparatus according to the present invention. This sheet rolling apparatus is roughly the same as the sheet rolling apparatus shown in FIGS. 5 and 6, in which a plurality of screw type extruders are arranged in parallel in the width direction of rolls in a single calender at predetermined intervals. . This sheet rolling apparatus is applied to rolling a sheet having a large width, but each screw type extruder does not have a large inner diameter according to the sheet width, and has a small inner diameter ( Generally, 60-90mm
φ) multiple screw cylinders are used.

The structure of this sheet rolling apparatus will be described more specifically. A plurality of extruders 11 for extruding a plastic material such as rubber, thermoplastics, or thermoplastic elastomers.
Are each provided with a feed section 12, a screw cylinder 13, and a discharge mouthpiece 14 of the head section. The mouthpiece 14 has a discharge passage 15a which is gradually flattened into a fish tail shape from the base end to the tip and at the same time widened.
A flat slit-shaped discharge port 15b suitable for sheet rolling is provided at the tip of the fish-tail type discharge path 15a. The necessary number of discharge ports 15b for sheeting the extruded plastic material. Rolls 16a-16c
The first roll 16a and the second roll 16b of the calendar 16 provided with are closely arranged to face each other. Each of the rolls 16a to 16c of the calender 16 has a roll size corresponding to the width of the sheet S to be rolled.

The screw cylinder 13 and the base 1
4, a porous breaker plate 17 equipped with a wire mesh strainer is provided. The breaker plate 17 supports a wire mesh strainer,
Adjust the extrusion pressure from the screw cylinder 13,
It has the functions of removing foreign substances and reducing pulsation in cooperation with the strainer. Further, the sheet rolling apparatus is provided with a temperature adjusting device 18, and the screw cylinder 13 is provided with a jacket 19 through which the heated water whose temperature is adjusted by the temperature adjusting device 18 flows through. The heated water from the temperature control device 18 is the first roll 1 of the calendar 16.
6a and the second roll 16b can also be used for heating, but these rolls can be provided with additional heating means.

An electric motor 20 for rotationally driving each screw 13a in a plurality of extruders 11 and a speed reducer 21 for reducing the rotation thereof are individually mounted on a base plate 23 together with each extruder 11. There is. These base plates 23 can be moved within a predetermined range in the width direction of the sheet rolling apparatus orthogonal to the sheet extrusion direction of the extruder 11 with respect to the substrate 25 by a slide mechanism having small wheels 24, and are not shown. It can be fixed at any position by the fixing device. This is an adjusting means for adjusting the distance D between the central axes of a plurality of extruders 11 arranged in parallel to an appropriate distance according to the plastic material to be rolled or the rolling conditions. It is what constitutes.

A plurality of the extruders 11 are arranged such that the widths of the rolls in the calender 16 are arranged such that the side edges of the sheets of the plastic material extruded from the adjacent extruding machines 11 and rolled by the calender 16 are joined together. It is installed in parallel in the direction. When the extruders 11 are juxtaposed at such intervals, the sheets of the plastic material extruded from the adjacent extruders are joined together in the vicinity of the joining line of the side ends thereof in a fusion state and the surfaces are integrated. The present inventor has already confirmed experimentally that a sheet S of a plastic material exhibiting a large width can be obtained. Therefore, when increasing the width of the sheet rolled by the calendar 16, it is possible to use a plurality of screw cylinders 13 having a small diameter in consideration of economical efficiency without increasing the inner diameter of the screw cylinder 13 in the extruder 11. In FIGS. 1 and 3,
Although the case where two extruders 11 using such screw cylinders 13 are arranged in parallel is shown, three or more extruders may be arranged in parallel.

An electric motor 26 is installed on the substrate 25, and the electric motor 26 allows the substrate 2 on the base pedestal 28 to be installed.
Wheels 27 for moving 5 in the direction of sheet extrusion in the extruder 11 can be rotationally driven. Therefore, by rotating the wheels 27 by the electric motor 26, the plurality of substrates 25 on which the extruder 11, the electric motor 20, and the speed reducer 21 are respectively mounted are separated from the calender 16 by the base 14 of the extruder 11 on the base pedestal 28. It is possible to facilitate maintenance such as moving in a direction in which the plastic material is moved and cleaning the plastic material when switching the type, and removing the screw 13a from the extruder 11.

In the above sheet rolling apparatus, in order to make the extrusion amount of the plastic material from the plurality of extruders 11 uniform and to evenly supply the material to the calender 16, the screws 13a of the plurality of extruders 11 are made uniform. It is possible to provide means for controlling so as to rotate at a constant speed. As the constant-velocity rotation control means, for example, the output (generated voltage) of a tachometer mounted on the rotation shaft of the screw 13a in each extruder 11 is compared, and each speed reducer 21 is adjusted so that they are constant.
It is also possible to use means for automatically finely adjusting the temperature, controlling the operation of each extruder 11 by a microcomputer, or the like.

Further, since the extrusion pressure influences the extrusion amount in the extruder, the pressure (extrusion pressure) in the die 14 at the tip of each screw cylinder 13 may be equalized to make the extrusion amount constant. it can. As a control means for controlling the extrusion pressure of the plastic material in the head portions of the plurality of extruders 11 to be equal pressure, a pressure sensor 30 for detecting the extrusion pressure is provided in the head portions of each extruder 11, and based on the output thereof. Means for finely adjusting the rotation speed of the extruder 11 via each speed reducer 21 can be used. Whichever of the above control means is adopted, instead of the electric motor 20 and the speed reducer 21, a continuously variable transmission motor whose rotation speed can be easily controlled can be provided to control the rotation thereof.

In the sheet rolling apparatus having the above structure, the screw 13a is decelerated by the rotation of the electric motor 20 and the plastic material is supplied from the feed section 12 of the extruder 11. The material is accompanied by the rotation of the screw 13a. From the screw cylinder 13 toward the mouthpiece 14 of the head portion, and has a fishtail type discharge passage 15a from the discharge outlet 15b of the mouthpiece 14 to the calendar 16
Is extruded as a flat sheet between the first roll 16a and the second roll 16b, and is rolled into a sheet through the space between the second roll 16b and the third roll 16c which is a cooling roll. Then, the sheet of the plastic material rolled by the calender 16 to have a predetermined sheet width and sheet thickness is guided to the winding device through the processing device at the next stage, for example, the trimming cutter.

In such a sheet rolling apparatus, for example,
Extruder 1 with screw cylinder 13 having an inner diameter of 90 mm
When the plastic rubber is extruded from the ejection outlet 15b at the tip end using the mouthpiece 14 having the fish tail type ejection passage 15a, it is extruded as a flat sheet having a width of 400 to 500 mm and a thickness of 7 to 10 mm, The calender 16 is rolled into a sheet having a width of 600 to 700 mm and an arbitrary thickness. When a plastic material having poor fluidity is extruded from the discharge port 15b to the calender 16 in the form of a flat sheet, the width of the extruded sheet is determined by the inner diameter of the screw cylinder 13 of the extruder 11. Even if the divergence angle of the fish tail discharge path 15a in the mouthpiece 14 at the tip of the machine 11 is increased, the width of the sheet extruded from the discharge opening 15b cannot be widened due to the restriction of the fluidity of the plastic material.

That is, there is a limit to the size of the opening width of the discharge port 15b of the mouthpiece 14 having the fish tail type discharge passage 15a with respect to the inner diameter of the screw cylinder 13. Also,
The rolling width by the roll of the calendar 16 for rolling the material extruded from the discharge port 15b of the extruder 11 is also the extruder 1
The material width supplied from 1 is restricted. That is, there is a limit to the rolling width of the sheet obtained by the single extruder 11. However, as described above, the side edges of the sheets of the plastic material extruded by the adjacent extruders 11 and rolled by the calender 16 are arranged so that the side edges of the sheets of the plastic material are joined to each other, and the extruder 11 is moved to the roll of the calender 16. When placed side by side in the width direction, the plastic material extruded from the adjacent extruder has a large width in which the side edges of the sheets of the plastic material are joined together in a fusion state in the vicinity of the joining line to form a sheet surface with an integrated surface. The sheet S can be obtained, and a sheet width exceeding the capability of a single extruder can be rolled.

Explaining this concretely, the width of the sheet that can be rolled with the discharge material from one extruder 11 is now 6
If it is 00 mm, when the distance S between the central axes of the two extruders 11 is properly adjusted and used, the width is 1200 mm.
Can be obtained, and when three extruders 11 are arranged in parallel, a sheet having a width of 1800 mm can be obtained. That is, a sheet with a large width that is extruded from a single extruder with a large cylinder inner diameter
It can be extruded by a screw cylinder with a small inner diameter considering economy.

Further, the extruder 11 using the screw cylinder having the small diameter described above enables delicate temperature control of the plastic material in the extrusion process as compared with the screw cylinder having the large diameter, and the actual thickness When a rubber sheet having a thickness of 0.2 mm was manufactured, the variation in the thickness of the rubber sheet at five points could be reduced to 1/100 mm or less. Further, in the above sheet rolling apparatus, as compared with the case of using a single extruder having a large diameter, the manufacturing cost of the apparatus is extremely low and the sheet forming capacity per hour is slightly small,
The manufacturing cost could be reduced to about 1/2. Moreover,
The power required for a plurality of extruders is about half that of an extruder having a large diameter, which is excellent in terms of energy saving.

[0026]

As described above, according to the sheet rolling method and apparatus of the present invention, when rolling a plastic material into a sheet, even if a plurality of screw cylinders having a small diameter are used, they are adjacent to each other in the calendar. The ability of the sheets to fuse together at their juncture enables the rolling of sheet widths beyond the capability of a single extruder, which results in the inner diameter of the screw cylinder of the extruder. In comparison with the above, the sheet width of rolling with a calendar can be made as large as possible. Therefore, the problem that occurs when the extruder becomes large, that is, the entire extruder becomes very large and expensive, and accordingly, the power for operating the extruder also becomes large, resulting in the production of the sheet. A wide sheet can be rolled while avoiding problems such as a significant increase in cost.

[Brief description of drawings]

FIG. 1 is a plan view showing the overall configuration of an embodiment of a sheet rolling apparatus according to the present invention.

FIG. 2 is a side view of the same.

FIG. 3 is a partially cutaway plan view showing a related configuration of a calender and heads of a plurality of extruders in the above-described embodiment.

FIG. 4 is a partial side sectional view showing the configurations of the extruder and the calender.

FIG. 5 is a plan view for explaining a configuration example of a conventional sheet rolling apparatus.

FIG. 6 is a side view of the same.

[Explanation of symbols]

 11 Extruder 13 Screw Cylinder 13a Screw 14 Base 15a Discharge Path 15b Discharge Port 16 Calendar

Claims (5)

[Claims] 1. A plastic material is flattened from a mouth of a mouthpiece having a fish tail type discharge passage in a head portion of a screw type extruder and sent to a calender, and when the plastic material is rolled into a sheet in the calender, The plastic material is extruded from a plurality of screw type extruders arranged side by side in the width direction of the roll in the calender, and the side edges of the sheets of the plastic material extruded from the adjacent extruders are fused with each other in the calender, and a plastic sheet with a large width A sheet rolling method, which comprises obtaining a sheet of material. 2. A sheet rolling apparatus for flattening a plastic material from a discharge port of a die having a fish tail type discharge passage in a head portion of a screw type extruder and sending it to a calender, and rolling the plastic material into a sheet in the calender. In the above, a plurality of the screw type extruders are arranged side by side in the width direction of the rolls in the calender with a gap such that the side edges of the sheets of the plastic material extruded from the adjacent extruders are joined to each other in the calender. Characteristic sheet rolling equipment. 3. The sheet rolling apparatus according to claim 2, further comprising adjusting means for adjusting the intervals between the plurality of extruders. 4. The sheet rolling apparatus according to claim 2, further comprising means for rotating the screws of a plurality of extruders at a constant speed. 5. A pressure sensor for detecting the extrusion pressure of the plastic material in the heads of a plurality of extruders is provided, and a control means for equalizing the extrusion pressures of the extruders based on the outputs thereof is provided. The sheet rolling apparatus according to any one of claims 2 to 4.