EP1140463A1

EP1140463A1 - Method and device for producing synthetic panels with undercut, one-piece extensions and a synthetic panel of this type

Info

Publication number: EP1140463A1
Application number: EP99955855A
Authority: EP
Inventors: Alfred Plammer
Original assignee: Alois Gruber GmbH
Current assignee: Alois Gruber GmbH
Priority date: 1999-10-19
Filing date: 1999-10-19
Publication date: 2001-10-10
Also published as: CA2351686A1; JP2003512200A; CA2351686C; AU1264400A; KR100587947B1; AU765123B2; WO2001028754A1; NO20012790L; US6908580B1; US7029265B2; NO318835B1; US20040109910A1; KR20010107990A; NO20012790D0; JP4409141B2; TW440516B; WO2001028754A8

Abstract

The invention relates to a device for the continuous and non-destructive production of synthetic panels which are provided with undercut anchor protrusions, profiled struts or other forms of extensions (28) on one or both sides. Said device comprises a temperature-regulated cooling roll (11) which contains peripheral cooling channels (15) in the roll body (17). The periphery of the roll body (17) is configured as a polygon with flat supporting surfaces (25) which lie against the moulding/demoulding slats (13) or are held above the latter. The moulding/demoulding slats (13) are displaced using pistons/cylinders (16) and piston rods (18). The piston rods (18) are displaced in transverse channels running through the roll body (17). The fused mass fills the moulds (27) of the moulding/demoulding slats (13) by means of the counter-pressure between the moulding roll (11) and a counter-roll (10) and is cooled. During the filling of the moulds (27), the moulding/demoulding slats (13) are pressed against the flat sections of the roll body (17). After cooling, the resultant synthetic panel (20) with anchor protrusions (28) or other extensions is released, without being damaged, by the opening of the moulding/demoulding slats (13). A synthetic panel which has been produced on a calender (3) of this type has undercut extensions (28) which are formed as one-piece with the synthetic panel (20).

Description

Method and device for producing plastic plates with undercut. one-piece approaches and such a plastic plate

The invention relates to a method for producing plastic sheets, preferably made of thermoplastic, which are provided on at least one side with undercuts, which are formed in one piece with them, the plastic being formed by extrusion from a flat die and then by at least one from two rollers formed nip is performed and at least one roller is provided with the undercut approaches corresponding shapes that are filled with the plastic. In addition, it also relates to a device for producing such plastic sheets and to these plastic sheets themselves.

Basically, the invention describes the continuous production of a plastic plate provided with anchor knobs or other shapes or approaches. The device according to the invention is used, for example, as part of an extrusion system for thermoplastics in order to extrude anchor plates, which, as a chemical-resistant lining or cladding for components such as pipes, pipelines, channels, basins, containers, columns, etc., are made of generally cement-bound materials, such as Concrete. The connection between the anchor knobs of the plastic plate and the component carrying the concrete achieves a positive connection.

The anchor plate is usually made from thermoplastic materials with high temperature and chemical resistance, such as polyethylene, polypropylene, PVC, PVDF, ETFE or E-CTFE in a continuous extrusion and calendering process. The plastic plate can be single-layer or in Co-extrusion processes can be extruded in multiple layers or laminated and coated as a single or multi-layer plastic sheet with aluminum or other substrates, fabrics or nonwovens made of polyester or glass fibers.

DE-296 15 818 U presents a device which mechanically squeezes trapezoidal elevations on a plastic plate in a second operation in such a way that an undercut shape is produced.

EP 0 436 058 B1 protects a mold that is created by pouring plastic melt into the wing-shaped mold nests of a roller. The molds are attached over the circumference of the roller and firmly connected to the roller. The melt fills an overall undercut wing-like shape, is cooled and removed from the roll in the cooled state. The individual sloping wings are not undercut. An undercut effect is achieved in that two wings are always assigned to one another in such a way that they are at an angle to one another.

DE 31 08 972 AI describes a method in which injection molds are connected by welding to a smooth plate to form an anchor plate. This process requires several operations: making the injection molds, making the plate, and welding the injection molds to the plate. This procedure causes high manufacturing costs compared to continuous extrusion.

Extrusion processes are also known from documents FR 1 102 294 A and US 2 816 323 and DE 29 34 799 AI, in which undercut web plates are extruded parallel to one another in the production direction. The products of these processes are suitable for the lining of cast concrete pipes, but show results in need of improvement in long-term creep tests. These multi-skin sheets are usually made from PVC in an extrusion process. The webs are shaped in a flat nozzle. The upper lip of the flat nozzle is made in the shape of the webs. The shear and Temperature sensitivity of the plastic PVC has so far made it possible to manufacture widths of up to approx. 1200 mm. When lining larger structures or concrete pipes with a larger diameter, several sections must therefore be welded together. These weld seams are weak points of the lining and cause additional manufacturing costs.

All of the above-described methods and devices for producing plates with undercut lugs lack the possibility of continuously producing lugs or anchors in the form of an upside-down cone or in the form of bar-shaped anchors transverse to the production direction in one operation. Some of the known methods impair the function of the anchor or knobbed plate due to subsequent deformation, damage or weakening of the anchor or plate or are not able to do so. In some cases, the processes are limited in the technically possible width or the minimum possible plate thickness.

The object of the invention is to provide a method and a device with which it is possible to create a continuous production of plastic plates of the type mentioned at the outset, that is to say anchor plates or knob plates, which have integrally formed undercut lugs or knobs , so that particularly non-positive anchor shapes can be provided in the intended installation in concrete structures, for example in the form of upside-down cones or pyramids or in the form of extruded cross-sections. These anchors or knobs should in no way weaken or damage the required connection between anchor and plastic plate.

This object is achieved in accordance with the invention in the proposed method in that the molds are provided in mold / demoulding strips arranged over the circumference of at least one roller, which are used for the non-destructive release of the undercut approaches formed Plastic plate are moved radially outward from the nip following the passage of the approaches. The proposed movement of the mold / final moldings can be obtained without a production delay in the manufacturing process when calendering the plastic sheet according to the invention. Following the passage of the dimpled plate dimensioned in terms of its thickness in the roll gap and the undercut approaches essentially formed there, the molding / demolding strips are moved in such a way that even sharp-edged undercut anchor knobs can be removed from the shaping roll without damage. After detaching the knobbed plate produced according to the invention, the molding / demolding strips are returned to their starting position in order to be available again for shaping the undercut lugs after the roller has rotated by almost 360 °.

According to the invention it is provided here that the molding / demolding strips are moved radially outwards. In this way, there is an uncomplicated release of the undercut anchor knobs after the passage of the plastic plate formed in the nip.

According to another feature of the invention, it is provided that the molds are each arranged approximately in half in adjacent mold / demoulding strips. In this way, a divisible shape is obtained, which further enables the non-destructive removal of the plastic plate provided with the undercut approaches from the roller provided with the shapes.

It is also within the scope of the invention that the plastic plate is extruded in one or more layers. In this way, substrates such as metal foils, fabrics or nonwovens can be incorporated into the plastic plate. It is also possible to provide the plastic plate according to the invention with, for example, a light-reflecting layer. In continuation of the basic idea of the invention, a modification of the method according to the invention is also proposed in such a way that the mold / demoulding strips are provided movably on the surface of a tempered flat plate and interact with a flat counter surface, the plastic being arranged between the plate and counter surface and is melted. In this embodiment, the method according to the invention is transferred to the plane. This modification is primarily used for the production of individual panels, primarily of smaller dimensions.

The device according to the invention for the production of plastic slabs with undercut, integrally formed lugs or knobs is distinguished from the prior art in that the molds for forming the undercut lugs are provided in mold / demoulding strips arranged over the circumference of at least one roller are, which are designed to be non-destructive release of the shaped undercut lugs of the plastic plate subsequent to the exit of the lugs from the nip. Just as in the method according to the invention, the movable mold / demoulding strips enable the undercut attachments and the plastic plate connected to them to be removed from the shapes of the attachments after passing through the nip without problems.

It is particularly advantageous here if, according to the invention, the molding / demolding strips are mounted such that they can be moved radially outwards and if the mold is also provided in each case about half in adjacent molding / demolding strips. In this way, a maximum opening area of the molds is achieved when they are moved outward from the surface of the roller or rollers having the molds.

A particularly advantageous development of the invention consists in that the molding / demolding strips can be moved hydraulically or pneumatically radially by means of piston / cylinder arrangements arranged in the rollers. With these Arrangements are proven mechanical components that ensure reliable operation of the device according to the invention.

The further feature according to the invention, namely that a roller shell of the rollers - in cross section - is designed as a polygon with flat partial surfaces, and that the mold / demoulding strips rest in the rest state over corresponding flat contact surfaces on the partial surfaces, serves the purpose of working reliably Contraption. The arrangement of flat partial areas over the circumference of the roll shell, against which the corresponding plane of the mold / demoulding strips rests in the resting or adjacent state, leads to a stable construction of the shaping roll.

As with the method according to the invention, the invention proposes as undercut approaches, in particular with respect to the flat plastic plate, upside down cones or pyramids. These can be provided as discrete or strip-shaped approaches. With the invention it is in particular possible to design web profiles arranged transversely to the production direction of the plastic slab as undercut approaches.

Finally, the invention also includes the plastic plate itself, which is produced according to one or more features of the method or the device according to the invention.

The roller in which the molds for forming the undercut approaches are provided is tempered. If the mold / demoulding strips are provided on a flat plate, this is heated.

The liquid plastic mass is filled by the pressure created in the nip between the shaping roller and a counter-roller, into the molds worked into the mold / demoulding bars, and then cooled and solidified. When filling the mold, the mold / demoulding strips lie on the tempered roller or the tempered plate. After the molds have cooled, the resulting anchor plate is released again non-destructively by lifting the mold / removal strips. The molds can be filled again after the rollers have rotated about 360 °.

With the invention, particularly non-positive anchor shapes can be produced economically, which could previously only be welded onto a smooth plate in several operations. By simply exchanging the movable mold release molds, different anchor shapes can be extruded without the time-consuming change of complete rolls on the same device and the same cooling roll. This means that different market segments and their different requirements can be served for multiple rollers without major investments. The previous limitation of the width of multi-wall sheets in the extrusion direction is overcome. This eliminates the expensive pre-assembly by welding.

Further details, features and advantages of the invention will become apparent from the following description of a preferred exemplary embodiment and from the schematic drawing and the claims. Show it:

1 shows an elevation of the device according to the invention, which is connected downstream of an extrusion system;

2 shows a cross section of three rollers for the continuous production of the knobbed plate according to the invention;

3 shows the roller provided with molding / demolding strips in a partial top view;

Fig. 4 is a partial section through the roller provided with the form / demolding strips in an enlarged view to show the drive of the movable strips or 5 to 10, partly in plan view and partly in section, different shapes of anchors and webs which, according to the invention, can be produced in one piece with the plastic plate carrying them in a particularly economical and non-destructive manner.

1 shows a known extrusion system with an extruder 1, a flat die 2, a three-roll calender 3, a take-off 4, a cooling section 5, an edge cutting device 6, a cross-cutting device 7, a winder 8 and a support table 9. In the extruder 1, the processed plastic is melted, homogenized and conveyed to the flat nozzle 2. It forms the melt into a liquid band. The shaped melt is poured from the flat die 2 into the first nip of the calender 3. It has rollers 10, 11 and 12, which are preferably arranged horizontally. The roller 11 is designed in the sense of the device according to the invention. The individual rollers 10 to 12 are individually driven and individually tempered. The task of the calender 3 is to shape and cool the melt into a plate or film with undercut attachments, anchor nubs or other attachment shapes. The trigger 4 immediately after the calender 3 is designed as a rubberized pair of rollers and is used for tension-free removal of the plastic plate or knob plate 20 produced, which is also referred to below as the anchor plate. On the subsequent cooling section 5, the plastic plate 20 cools further, and there is the edge cut 6. After a second take-off 4, the plastic plate 20 is cross-cut into the desired lengths 7. The winder 8 winds up thin plates, the support table 9 takes the rigid plates on.

2 shows the device according to the invention in use as a shaping cooling roll 11 and a counter roll 10 with a smooth surface in the horizontal three-roll calender 3. The device according to the invention consists of the roll 11 and a stable roll jacket 17 which has peripheral cooling bores 15 on the circumference over the entire bale length of the roller. The cooling holes 15 lead the roller 11 through the plastic melt supplied heat again. The temperature on the roll surface and in the shaping areas of the roll is kept constant. The outer surface of the roll shell 17 is designed in cross section as a polygon, for example with a division of 32 flat locations, ie flat bearing surfaces 25. The bearing surfaces 25 are arranged on the circumference in such a way that they alternate with the peripheral cooling bores 15. Therefore, the flat bearing surfaces 25 can be drilled through transversely to the roller jacket 17. Through these bores, strips 13 are moved up and down on the roller 11, which are used for forming and demolding anchor plates according to the invention and are referred to below as molding / demolding strips 13. They have in their long sides machined forms 27 for the lugs or anchor nubs 28 of the nub plate 20 and are provided in the area of the surface of the roller 11 parallel to the longitudinal axis of the roller.

The molding / demolding strips 13 are preferably opened and closed by means of hydraulic or pneumatic piston cylinders 16. The Forn demoulding strips 13 are pressed against the flat bearing surfaces 25 of the roll shell 17 when the molds 27 are filled. In the gap between the roller 10 and roller 11 there is a linear pressure which presses the liquid plastic melt from the flat nozzle 2 into the molds 27 of the mold / demoulding strips 13 resting on the roller shell 17. After the melt has cooled to form an anchor plate 20, the molding / demolding strips 13 are raised by means of the piston / cylinder 16 and the piston rods 18 arranged over the entire bale length, and the anchor plate 20 is released non-destructively and pulled off via the roller 12. The pistons of the piston / cylinder arrangements are provided with the reference number 29.

FIG. 3 shows a top view of the device according to the invention consisting of the film / demoulding strips 13 and molds 27 on the long side of the mold / demolding strips for shaping the armature 28. Fig. 4 illustrates in section the structure of the device according to the invention with the roller jacket 17 with the flat bearing surfaces 25 on the outer surface and the cooling bores 15, the mold-demolding strips 13, which are moved by piston rods 18 in cylinders 16. The opening / closing of the molding / demolding strips 13 is preferably carried out hydraulically or pneumatically. The time of opening and closing of the molding / demolding strips 13 via the piston rod 16 can be controlled mechanically via control disks or electrically via solenoid valves.

An anchor plate 20 installed in concrete 21 is shown in section in FIG. 5. It is used as formwork and the concrete is poured in liquid form behind the anchor plate. Fig. 5 shows the excellent non-positive connection between the anchor plate and the concrete.

The anchor plate 20 can be produced continuously in an extrusion process with the aid of the device according to the invention.

The shape of the lugs or anchors 28 or other shapes is determined by the shape 27 selected in the mold / demoulding strips 13. The forms 27 are incorporated according to the invention on the long side of the molding / demolding strips 13. This, together with the movable arrangement of the FornWEntform bars 13, enables the non-destructive demolding of undercut approaches 28. The shaping roller 15 can be used with differently designed shaping / demolding bars 13. This makes it flexible to use and can be quickly converted to new shapes by exchanging the FornWEntform moldings.

Fig. 6 shows a top view of the anchor plate 20 with round shapes such that the anchor 28 is like a cone turned upside down.

Fig. 7 shows the anchor 28 as an upside down pyramid. Fig. 8 shows the section of an anchor plate with webs 19, which is non-positively integrated in the concrete 21. In Fig. 9 the anchor plate 20 is provided with webs 19 which practically extend across the width of the plastic plate 20. The webs 19 can be extruded continuously and non-destructively across the production direction. The form / demolding strips 13 of an anchor plate 20 with webs 19 are shown in FIG. 10. Anchor plates 20 with webs 19 are preferably used for the lining of concrete pipes, in particular when the width of the anchor plate 20 corresponds to the length of the concrete pipe and is therefore expensive

Confectioning work for the anchor plates is eliminated. The cross-sectional shapes of the lugs, anchors or knobs 28 shown in FIGS. 4 and 10 can be both discrete lugs and continuous webs 19.

The forms 27 incorporated into the FornWEntform strips 13 can be positive or negative, i.e. protruding or recessed on the strips 13 or on the roller jacket 17. The shapes can be cylindrical, with a positive or negative cone, undercut, grooved in the longitudinal or transverse direction, pyramid-shaped or in combinations thereof. They can have a round, square, rectangular, oval or polygonal cross-section, T-shaped groove or a combination thereof. The surface of the molds can be smooth, grooved, polished, roughened, eroded, spirally milled, drilled, grooved, or a combination thereof. The dimensions of the molds depend on the height and width of the mold / demoulding strips 13 and on the stroke of the hydraulic or pneumatic cylinders. The distance between the molds depends on the width and length of the mold and demoulding strips. Radial or axial vents in the roll shell or in the mold and demoulding strips improve the continuous shaping of the mold.

An economical application of the device according to the invention is the continuous extrusion of anchor plates made of thermoplastic materials for corrosion protection and the insulation of buildings and structures made of concrete.

Claims

claims

1. A method for producing plastic plates (20), preferably made of thermoplastic, which are provided on at least one side with undercut, integrally formed lugs (28), the plastic being formed by extrusion from a flat die (2) and then through at least one roller gap formed from two rollers (10, 11, 12) is guided and at least one roller (11) is provided with molds (27) corresponding to the undercut projections, which are filled with the plastic, characterized in that the molds (27 ) in the at least one roller (11) arranged FornWEntform strips (13) are provided, which for the non-destructive release of the formed undercut lugs (28) of the plastic plate following the passage of the lugs (28) from the nip radially outwards be moved.

2. The method according to claim 1, characterized in that the FornWEntform strips (13) are moved radially outwards.

3. The method according to claim 1 or 2, characterized in that the radially outwardly moving mold / demoulding strips (13) after demolding the lugs (28) generated in them are moved back to their starting position.

4. The method according to at least one of claims 1 to 3, characterized in that the molds (27) are each arranged approximately half in adjacent mold / demoulding strips (13).

5. The method according to at least one of claims 1 to 4, characterized in that the plastic plate (20) is extruded in one or more layers.

6. The method according to claim 5, characterized in that the plastic plate (20) is coextruded with substrates such as metal plates, fabrics or nonwovens.

7. Modification of the method according to claims 1 to 6, characterized in that the FornWEntform strips (13) are movably provided on a substantially flat surface of a tempered plate, and cooperate with a corresponding counter surface, the plastic being between the plate and counter surface is arranged and melted.

8. Device for producing plastic plates (20), preferably made of thermoplastic, which are provided on at least one side with undercut, integrally formed with them approaches (28) with an extruder (1) and a flat die (2) through which melted plastic can be fed to a nip formed by two rollers (10, 11, 12), at least one of the rollers (11) being provided with molds (27) corresponding to the undercut projections (28), characterized in that the molds (27) In the at least one roller (11) arranged form / demoulding strips (13) are provided, which for the non-destructive release of the shaped undercut lugs (28) of the plastic plate (20) following the exit of the lugs (28) the nip are designed to be movable.

, Apparatus according to claim 8, characterized in that the shaped-molded strips (13) are mounted so as to be movable radially outward.

10. The device according to claim 8 or 9, characterized in that the molds (27) are each provided approximately half in adjacent mold / demoulding strips (13).

11. The device according to at least one of claims 8 to 10, characterized in that the FornWEntform strips (13) by means of the rollers (10, 11, 12) arranged piston / cylinder arrangements (16) are hydraulically or pneumatically movable radially ,

12. The device according to at least one of claims 8 to 11, characterized in that a roll shell (17) of the rolls (10, 11, 12) - in cross section - is designed as a polygon with flat partial surfaces (25), and that the FornWEntform- In the resting state, strips (13) rest on the partial surfaces (25) via corresponding flat contact surfaces (26).

13. The device according to at least one of claims 8 to 12, characterized in that the molds (27) incorporated into the FornWEntform strips (13) are designed as discrete upside down cones or pyramids.

14. The apparatus according to claim 13, characterized in that the conical or pyramidal shapes are provided as strip-shaped recesses arranged transversely to the direction of production of the plastic plate (20).

15. The device according to at least one of claims 8 to 14, characterized in that are designed as web profiles arranged transversely to the direction of production of the plastic plate (20).

16. Modification of the device according to claims 8 to 15, characterized in that for the intermittent production of individual plastic plates, the mold / demoulding strips (13) are provided on a flat plate, which interact with a flat counter surface, between the plate and Counter surface of the plastic, in particular as granules, is provided and can be melted.

17. plastic plate (20) with one-piece provided, undercut approaches, produced by the method at least one of claims 1 to 7.

18 plastic plate (20) with one-piece provided, undercut approaches, produced on the device according to at least one of claims 8 to 16.

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