JPS60234818A - Method and device for manufacturing extruded web reinforced multilayer board consisting of thermoplastic plastic - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Industrial applications The invention is made of thermoplastic.

The present invention relates to a method and apparatus for manufacturing an extruded web-reinforced multilayer board having a web corrugated in the extrusion direction.

PRIOR ART A web-reinforced laminate consisting of two parallel plane outer walls, an inner wall optionally arranged parallel to these, and a web arranged in one piece between these outer walls (the laminate is a heat-insulating, lightweight and strong It is extremely important industrially as a window frame or roofing material.The web-reinforced multilayer board has a strong web reinforcement effect.
Self-supporting arrangements can be made in the web direction over large spans, although the stiffness transverse to the web direction is still insufficient. In fact, web-reinforced multilayer boards with webs corrugated in the extrusion direction have a high lateral stiffness. However, conventional multilayer boards have been industrially disadvantageous due to the high cost of equipment for manufacturing them.

From Swiss Patent Specification No. 457829.

A method is known for producing hollow profile plates with corrugated intermediate webs using special extrusion dies. The corrugated arrangement is obtained by periodically moving the cores between which the web is formed laterally within the die opening. As a result, the intermediate web inside the plate is extruded in a corrugated manner, and the web at the side edges is formed as a solid profile with varying widths, which leads to high material consumption and stresses in the material. .

Periodically moving the die core provided with the core bin is technically expensive.

Another principle for corrugating the web is apparent from DE 27 34 464 A1. In this case as well, a specially constructed extrusion die is required. During extrusion molding of hollow strands, by periodically varying the flow resistance of the molding material in the die hole, the portions of the outer wall of the web-reinforced multilayer board located between the rising positions of the webs are Thick and thin sections are alternately formed in such a way that the thick and thin sections are juxtaposed. Subsequently, the strand is stretched biaxially or triaxially in the thermoplastic state.

In this case, the thicker sections are stretched slightly more than the thinner sections. This causes the web to separate at various distances during stretching,
This results in undulations with a periodicity of successive thick and thin sections. In this case, adjacent webs are continuously corrugated in opposite directions.

OBJECT OF THE INVENTION It is an object of the invention to simplify the production of web-reinforced multilayer boards made of thermoplastics and having corrugated webs, and in particular to simplify this production process in a conventional manner without mechanically moving parts. The process was carried out using an extrusion die. Yet another object is to avoid the disadvantages of web-reinforced multilayer boards produced by known methods.

SUMMARY OF THE INVENTION The present invention provides a method for extruding thermoplastics into hollow strands through a slit die containing core bins in the die slits to form a web, and subsequently forming the extruded hollow strands. Die (Form
The starting point is a process for producing an extruded web-reinforced multilayer board by sizing and cooling in a molding die (Kana I) and drawing off the cooled hollow strand after exiting the forming die. According to the invention, in order to form a corrugated web in the extrusion direction, at least one side of the extruded hollow strand in the forming die, to the extent that the hollow strand is still above its softening temperature, is A friction force that periodically alternates in direction is applied by intersecting with the

For this purpose, at least one forming die wall is
special forming dies are used, in which the parts in the inlet region of the forming die are arranged movably in alternating cycles in a periodic manner transverse to the extrusion direction, and the subsequent parts on the forming die wall are fixedly arranged; Or conventional forming dies movably arranged in the same way as a whole are used.

In both cases, a lateral movement of the forming die or a movable member of the forming die wall applies a frictional force transverse to the extrusion direction to the extruded hollow strand. This causes the outer wall of the hollow strand, which is in contact with the moving forming die wall, to move together, so that the web connected to the outer wall has a path inclined in the direction of extrusion. When the direction of motion changes, the direction of the inclined path also changes. In this way, by periodically changing the direction of movement, a corrugated web path is obtained.

Slit dies without mechanically movable built-in parts, which are customary for the production of web-reinforced multilayer boards, can be used in the method according to the invention. Since the technical construction of a forming die is significantly simpler than that of an extrusion die, the incorporation of a movable part in the forming die wall requires less technical effort than the incorporation of a movable part into an extrusion die. . A laterally movable arrangement of the entire forming die is also a structurally simple solution.

The advantage that the web-reinforced multi-layer board according to the invention has over web-reinforced multi-layer boards produced according to the known technology using slit dies with vibrating core bins is that the peripheral webs have a uniform width, which reduces material consumption. Stresses due to significantly different web widths are reduced and avoided.

A corrugated path web results in the side edges and the outer wall members in the area between the rises of adjacent webs having a thickness that varies with the period of web corrugation. This variation thereby results in the outer wall region being such that the web initially placed inside the hollow profile extends farthest away from the side edges of the web-reinforced multilayer board and, conversely, the web contacts closest to the side line. This results in a compressed position. A similar thickness variation in the chamber located at one periphery for other reasons also occurs in the web-reinforced multilayer board produced according to DE 27 34 464 A1. In contrast to these, the webs in the web-reinforced multilayer board according to the invention are continuously and evenly corrugated, which results in an increased transverse stiffness and the outer wall area between the web rises is not stretched and evenly corrugated. It has a thickness.

Compared to conventional web-reinforced multilayer boards with linearly extending webs, the transverse stiffness of the board according to the invention is clearly greater. This effect increases with amplification of the corrugations.

EXAMPLE It is of practical importance in the process according to the invention that the hollow strand can still be formed at its softening temperature within the range of the frictional forces of the forming die transverse to the direction of extrusion, so that it can be formed in the thermoplastic state. It is to be. Deformation in the plastic region of the plastic material produces only a slight orientation and resiliency, so that structural variations once induced are well maintained without the application of external forces.

The method according to the invention can be carried out using all thermoplastics which can be extruded in the thermoplastic state into hollow strands of the shape in a slit die of conventional construction and sized and cooled in a forming die. . These plastics include extrusion molding materials made of 1-dimethyl methacrylate, polycarbonate, polyvinyl chloride, propylene, polystyrene, and the like.

The present invention will be explained in detail below with reference to drawings and embodiments.

In that case, in FIG. 8, the rising line from the upper outer wall of the web is represented by a solid line, and the rising line from the lower outer wall is represented by a broken line, and furthermore, in FIGS. 5, 6 and 7,
The dashed line represents the projected line of the rotating Queso toward the cross section.

In FIG. 1, 1 represents a slit die in which a series of core bins 3 are incorporated in the die slit 2 to form hollow chambers and webs dividing them from each other. Depending on the desired chamber shape, these core members can have a rectangular, triangular or frustoconical cross section. The extruder connected to this slit die is designated by 4.

The hollow strand 5 extruded from the slit die enters the forming die 6. The forming die is preferably a slit die with a diameter of several millimeters, generally 5 to 50, preferably 1
They are placed at a distance of 0-20 mm. The forming die can be cooled by a coolant flowing through the holes 7, for example. The hollow strand is supported in contact with the forming die by a gas pressure that is greater than the pressure in the forming die. It can be formed by reducing the pressure in a gas pressure of 1, 2, 1, 7, or 7.

In embodiments using movable parts of the forming die, which are fixed except for the movable parts, the side walls are invariably fixedly arranged. Advantageously used is a vacuum forming die which contains exhaust grooves 8 in the die wall and side walls.

These side walls are not shown in FIG. 1; they represent the connection of the upper and lower walls of the forming die.

At the inlet of the forming die, a movable member 9 of the forming die wall is placed on at least one side, preferably on both sides, of the hollow strand.
or 9' is arranged.

This direction of movement extends perpendicular to the cross section shown in FIG. Any drive device 1 that operates cyclically, for example a periodically controlled hydraulic device or an eccentric device, can be used to move the wall element 9 or 9'. an eccentric device induces a velocity of movement that increases or decreases according to a sinusoidal function;
This also results in the formation of a sinusoidal wavy curve. For example, if a periodically switchable rack mechanism is used and the rack is moved at a constant velocity, a wavy path with a zigzag shape is obtained. Optionally, the movement of the forming die wall member can also be interrupted at an end point or an intermediate point, so that multiple frame- or step-shaped undulating paths are obtained.

According to another embodiment of the method, the frictional force acting on the extruded strand is obtained by moving the entire forming die relative to the slit die.

In this case, the forming die is arranged movably in periodically alternating directions transverse to the extrusion direction. The method of this embodiment has the advantage that a conventional forming die without moving parts is sufficient.

The relative movement between the slit die and forming die is 1
Optionally, the slitting die is reciprocated in front of the forming die in a fixed position.

Alternatively, the slit die may be fixedly arranged and the forming die may be reciprocated.

The latter method is advantageous. Advantageously, the movably arranged device parts are moved on a roller mount using an eccentric drive. Generally, the slit die must be reciprocated as a unit with the extruder feeding it, a cooling grate connected to the cage, and a take-off device. If the extruded strand is not wider than 200 to 300 mm or is made of thin-walled elastic plastic, the pulling device is fixedly placed at a sufficient distance from the rear end of the forming die, and only the forming die is reciprocated. You may move it. On the other hand, if the strands are clearly wide, their elasticity in the brittle material and rugged rigid structure is insufficient to overcome the relative motion without breaking.

The lateral stiffness of the web-reinforced multilayer board is advantageous.

This is the case when the waveform amplitude A is 0.5 to 2 times the average interweb distance B, in fact at least 10 to 30 mm. Because there is a constant slippage between the movement of the forming die wall and the movement of the hollow strand.

The forming die wall or the forming die itself
Large distance 1 For example, the average distance between webs or the space between core parts in a slit die of 0-5 to 4
It is sufficient if it can be moved twice as much.

When the relative motion amplitude is large, the side edge of the hollow strand separates from the side wall of the forming die.

There is a concern that this can often result in the formation of unfavorable wavy edges. This risk can be counteracted by increasing the vacuum in the forming die or by expanding the slit die width. That is, if the slit die is wider than the forming die by half or the full height of the amplitude, peeling of the side edges can be almost completely prevented.

The hollow strand to be cooled is withdrawn from the forming die 6 using a withdrawing device 1, for example a roller set 10/11. The desired curved path is obtained by an advantageous ratio of the withdrawal speed and the period of alternation of direction of the forming die wall. A wavelength W of 1 to 20 times the average interweb distance B causes a periodic directional alternation of the frictional force after a strand section whose length corresponds approximately to 0.5 to 10 times the average interweb distance has been taken off. Obtained when implemented each time.

When frictional force is applied only to one side of the hollow strand,
The web rising line on this surface is formed into a wave shape, and
The web rise on the other side remains straight. In this way, a web reinforcing plate having the cross section shown in FIG. 7 is obtained. Advantageously, frictional forces are applied to both sides of the hollow strand. If frictional forces are applied continuously in the same direction, a web reinforcing plate having the cross section shown in FIG. 3 is obtained. This is achieved very simply by mechanically coupling the parts 9 and 9' and moving them cyclically with the same drive, or by moving the forming die as a whole cyclically. On the other hand, if the forming die wall is moved by a drive device constantly operating in opposite directions, as shown in plan view in FIG. 4 and in cross-section in FIGS. The web rise lines of the upper and lower outer walls are each oppositely corrugated.

Example A thermoplastic polycarbonate molding material is fed into a hollow profile die 1 from an extruder with a screw diameter of 60 x m. The material temperature is 270'C and the die temperature is 260C. The strand 5 is carried out at a speed of 1 m/min. The width of the hollow irregularly shaped strand is 250 m and the height is 1611L1L. This strand is.

It has 16 hollow chambers with a rectangular cross section. The outer wall and web thicknesses are approximately the same and approximately 1 inch thick. This material strand is 500 m long at 20 mm behind the die.
The sample is introduced into a sizing die 6 having a length of m. In the first 100 Il of this sizing die, a sizing surface is arranged movably relative to the outer wall of the hollow profile 5. These sizing surfaces are reciprocated in the same direction, transversely to the extrusion direction, by an eccentric drive.

Adjust the temperature of the movable sizing member to 100°C. The temperature of the other sizing die is 50'C. 500 dragon (water column) for the movable and fixed parts of the sizing die.
Apply a vacuum. Movable size:) y 1 side/7+14
'F4w1(IL ha+n-m5 +1M i'-+
- the amplitude of the movement is 15, corresponding to the eccentric plate diameter 301111
It's my friend. The hollow profile plate discharged from the sizing die has a sinusoidally corrugated web. The amplitude of the resulting sinusoidal function is 8 mrtr. Wavelength Wld, 10
It is 0 mm. The cross section of this hollow irregularly shaped plate is formed as shown in FIG.

The outer wall has one peripheral chamber 12.13 as shown in FIG.
Depending on the distance between the first inner web 14 or 15 and the peripheral web 16 or 17, it is thinner than the rest of the plate by stretching <'(18)4 or by compressing it. Thickness<(19) is formed.

In another embodiment of this method, the sizing die is movably arranged and reciprocated transversely to the extrusion direction by an eccentric drive. Other operating conditions were the same as above.

The hollow profiled plate discharged from the sizing die has a sinusoidally corrugated web shape as in the previous method.

A R1 art n) itself 86 →-YoH Rollo FIG. 1 is a longitudinal sectional view schematically showing an embodiment of an apparatus for carrying out the method according to the invention, FIG. 2 is an embodiment of a multilayer board according to the invention A plan view partially showing the example web structure, Figure 3 is the same as in Figure 2.
4 is a plan view partially showing the web structure of another embodiment, and FIGS. 5 and 6 are a cross-sectional view taken along the line XX and IV-IV in FIG. 4, respectively. A cross-sectional view, FIG. 7 is a cross-sectional view partially showing the web structure of another embodiment, and FIG. 8 illustrates the structure of the peripheral part of the multilayer board shown in FIGS. 2 and 3. FIG.

1...Slit die, 2...Die slit, 3...
・Core bin, cow...extruder, 5...hollow strand 6...forming die, 7...cooling pipe, 8...
...exhaust groove, 9...movable wall member, 10.11...take-up device.

12.13...peripheral chamber, 14.15...first
Inner web, 16.17...peripheral wafer, 18Ff
G, 4 FIG, 5 FIG, 6

Claims (1)

[Claims] 1. Extruding the thermoplastic into a hollow strand (5) through a slit die (1) containing core bins (3) in the die slits (2) to form a web;
Then, the extruded hollow strand (5) is sized and cooled in a forming die (6), and the cooled hollow strand (5) is taken off after being discharged from the forming die (6) to form a wave shape in the extrusion direction. In manufacturing a large reinforced multilayer board with a reinforced web,
In the forming die (6), the extruded strand (
5) from a thermoplastic, characterized in that a frictional force of alternating directions is applied in one cycle, transversely to the extrusion direction, on at least one side within a range in which it is still above its softening temperature. A method for manufacturing an extruded web-reinforced multilayer board consisting of: 2. The extruded web-reinforced multilayer board made of thermoplastic plastic according to claim 1, wherein the frictional force is generated by moving the surface of the forming die in a direction crossing the extrusion direction. Manufacturing method. 3. The method for manufacturing an extruded web-reinforced multilayer board made of thermoplastic plastic according to claim 2, characterized in that the frictional force is created by moving the entire forming die in the lateral direction. 4. A friction force was placed on the inlet side of the forming die. It is characterized in that it is formed by moving at least one member of the forming die surface in the lateral direction. Bf!
j. A method for producing an extruded web-reinforced multilayer board made of thermoplastic silastic according to claim 2. 5. A method for producing an extruded web-reinforced multilayer board made of thermoplastic plastic according to claim 1, characterized in that a frictional force is applied to both sides of the extruded strand. 6. A patent claim characterized by applying a frictional force that alternates at the same period and constantly acts in the same direction on both surfaces.''
A method for producing an extruded web-reinforced multilayer board made of the thermoplastic plastic according to item 5. 7. A method for producing an extruded web-reinforced multilayer board made of thermoplastic plastic according to claim 5, characterized in that frictional forces that alternate in the same period and constantly act in opposite directions are applied to both surfaces. . 8. From a thermoplastic according to any one of claims 1 to 7, characterized in that a periodic alternation of the direction of the frictional force is carried out in each case over its length. The extruded web reinforced multi-layer plate is manufactured using the % ship method. 9. A gas pressure is maintained in the chamber located at the periphery of the extruded hollow strand, which is greater than the pressure acting on the lateral interface of the strand in the forming die. A method for producing an extruded web-reinforced multilayer board made of the thermoplastic silastic according to any one of Items 1 to 8. 10. Extruding the thermoplastic into a hollow strand (5) via a slit die (1) containing core bins (3) in the die slits (2) to form a web and subsequently extruding the extruded hollow strand (5). ) is sized and cooled in a forming die (6) and the cooled hollow strand (5) is withdrawn after removal from the forming die (6), thereby producing a web-reinforced multilayer board with a web corrugated in the extrusion direction. In a forming die (6), the extruded strand (5
), in which a frictional force of alternating directions is applied in one period to at least one side within a range in which this is still above its softening temperature, transversely to the extrusion direction,
Extrusion type (4), connected to it. A slit die (1) containing core bins (3) in the die slit (2) for forming a web, and two parallel plane forming die walls arranged behind the slit die (1); In an apparatus consisting of a coolable forming die (6) containing fixed side walls forming the sides of the forming die (6), as well as a take-off device (10, 11) arranged behind the forming die (6), the forming die (6) ) are arranged movably as a whole in periodically alternating directions transverse to the extrusion direction, or at least one
The forming die of the wall. The member (9, '9') within the forming die entrance area is
It is characterized in that it is arranged movably in periodically alternating directions transverse to the extrusion direction and that the subsequent parts of the forming die wall (9, 9') are fixedly arranged. A manufacturing device for extruded web-reinforced multilayer plates made of thermoplastic plastic. 11. Extruded web reinforcement multilayer made of thermoplastic according to claim 10, characterized in that elements (9, 9') of the same size on the two forming die walls are movably arranged. Board manufacturing equipment. 12. The apparatus for producing an extruded web-reinforced multilayer board made of thermoplastic plastic according to claim 11, characterized in that these members (9, 9') are arranged movably in the same direction. 13. An apparatus for producing an extruded web-reinforced multilayer board made of thermoplastic plastic according to claim 11, characterized in that these members (9, 9') are arranged movably in opposite directions. 14. The heat according to any one of claims 10 to 13, characterized in that the forming die (6) is provided with exhaust grooves (8) on the die wall surface and side wall surface. A manufacturing device for extruded web-reinforced multilayer plates made of plastic plastic. 15. The movable members (9, 9') of the forming die wall are
Any one of claims 10 to 14, characterized in that it is movable by a distance of 0.5 to 4 times the average distance of the space between the core bins (3) in the slit die (1). An apparatus for producing an extruded web-reinforced multilayer board made of the thermoplastic plastic described in 2.