DE2732866A1 - EXTRUSION PROFILES AND SHAPE HERE - Google Patents

Description

PATENT ADVOCATE DR. HANS-GUNTHER EGGERT, DIPLOMA CHEMIST

9 7 * 3 9 ft R R

5 COLOGNE 51, OBERLÄNDER UFER £ 90 / O £ O O

Cologne, July 19, 1977 93

Progress Plastics Ltd., 85 Keith Road, Winnipeg, Manitoba (Canada)

Extruded profiles and form therefor

The present invention relates to extruded profiles and, more particularly, to those having an expanded cellular shape Have thermoplastic core, which is covered by a thermoplastic coating practically at the same time together with any cross-section, as well as a method for the production thereof and an apparatus to carry out this process, the resulting product being useful for manufacture, for example of doors and panels as well as center posts for windows, door posts, decorations, panels, columns, accessories and the like is.

In the manufacture of any structure, it is preferred to use inexpensive material, the properties of which are suitable for the final formations are sufficient to reduce the number of manufacturing steps to incorporate this material into the to bring shaped desired end products. While many articles are initially made entirely of wood or metal usually a number of stages of manufacture

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was necessary, the greater cost of wood or metal made both less attractive to industry.

Furthermore, not all properties are shared by wood or a Possessing metal is desirable for the final product. Hence, the industry moved to the use of other materials over, which are either preferably used alone or together with other material.

One such material was PVC (polyvinyl chloride), which is abrasion resistant, is hard and is pleasant to the eye. However, it became less attractive because of its cost. Therefore It is not often used solely to make an article from it, but rather to make a to coat preformed wooden core. For example, U.S. Patent 3,432,885 describes an extruder for extrusion a plastic layer over a preformed wooden core. However, this structure is costly both in terms of that Material as well as in terms of manufacturing costs, which require at least two stages in the manufacturing process, pre-fabricating the wood core and extruding the plastic coating over the preformed wood core.

A less expensive material than PVC is foamed cellular or blown cellular PVC. However it is due to its softness, its destructibility by cold weather, and its loss of color if it is continuous Exposed to sunlight, solely for the purpose of extrusion of an article as a solid piece of foamed material PVC or unsuitable as a coating material.

It is therefore the object of the invention to provide extrusion products which are cheap to produce, but which are desired external properties in terms of hardness, good looks and

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Have weather resistance, but are still cheap.

The invention therefore relates to an extruded profile, consisting of a foamed, thermoplastic core covered by an outer thermoplastic coating predetermined cross-section is covered, wherein the foamed thermoplastic core in intimate compressed engagement with the inner wall of the outer coating during essentially simultaneous extrusion of the core and the outer Coating is expanded in that the foamed material is outwardly against the outer coating expanded during the extrusion process and exerts an outward force on the outer coating, which the outer coating has withstood.

The outer coating can be relatively thin and also made of rigid PVC, while the foamed core is made of foamed PVC can exist.

The invention also relates to a method for producing an extruded profile with the following stages:

a. substantially simultaneous separate supply of fluid, foamed, thermoplastic material to the Formation of the core and fluid thermoplastic material to form the coating in a separate one middle or an edge part of a channel of desired cross-section and adjacent by an extrusion die the entrance of the canal,

b. Fusion of the coating and the foamed core material between the inlet and the outlet, wherein the cellular core material expands and one after exerts an outward force against the outer coating material.

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A partition wall can be arranged in the entrance to separate the central and edge parts that lie between the Entry and exit ends and the formation of a coating before fusing with the foamed core, material enables. The partition wall can be evenly thick, with the outer surface running parallel to the wall, which forms the channel. The partition wall can on its inside adjacent to the middle part to the outside against the Edge part be formed inclined from the entrance to the exit. The wall can be adjacent to a thicker section have the inlet, which leads to a thinner section between the inlet and the outlet in the wall thickness is reduced by the fact that the inside adjacent the central part of the channel outwardly from the edge part Entrance is inclined in the direction of the exit.

The invention also relates to a method for producing extruded profiles with the following steps:

a. substantially simultaneous separate supply of fluid, foamed, thermoplastic material to the Formation of the core and fluid thermoplastic material to form the coating in a separate one middle or an edge part of a channel of desired cross-section and adjacent by an extrusion die the entrance of the canal,

b. Allowing the cellular, foamed material to expand evenly as it passes through the channel the mold is guided to the outlet and

c. Fusion of the coating and the expanded, foamed Core material between entry and exit, if the cellular core material continues, expand with an outward force being exerted through the foamed material.

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The uniform expansion of the cellular, foamed material can be achieved by continuously increasing the Cross-sectional area of the central part of the channel of the mold accompanied by the foamed material through guided the entry into the position between entry and exit and enables such a uniform expansion will.

The uniform expansion can be performed with any of the above Partition wall are made. The partition wall can have the same cross-sectional configuration as the canal exhibit.

The manufacture of such extrusions from thermoplastic After the steps described, material requires subsequent cooling and stripping in a known manner of the shape, if necessary, to maintain the cross-section of the product.

The invention also relates to a mold for an extruder which has inlet means for feeding in foamed Core material and coating material are selected. different Parts of the mold are provided for forming the core and the coating, the part for manufacture of the core lies within the part for making the coating, while exit means and a partition wall are provided in the mold, the latter separating the two parts and ending between the entry and exit means, to allow the coating part to fuse with the foamed core material, the foamed core material is expanded into engagement with the coating part.

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The expansion to fusing can be done in a controlled manner take place. The inside of the partition used to control the even expansion of the foamed core and is in contact with the core material as the core material is passed through the mold inclined outwardly from the core forming part and downwardly from the entrance end to the exit end and in one position end between the entry and exit ends.

Further refinements of the invention can be found in the following description and the subclaims.

The invention is described below with reference to the preferred embodiments shown in the accompanying drawings explained in more detail.

FIG. 1 shows, partially exploded, a mold according to the invention for use with an extruder.

FIG. 2 shows a section through part of an extruder with the shape of FIG.

Figures 3, 4 and 5 show in section extruded profiles, which can be produced according to the invention.

FIG. 6 shows, partly in section, a further embodiment of the mold according to the invention.

In FIGS. 1 and 2, a mold 10 according to the invention is shown, which has two mold plates 12 and 14. The shape 1o has an entry end 16 and an exit end 18 (the latter can only be seen in FIG. 2) and a channel 2o which runs through and is delimited by an annular wall 21. Adjacent the inlet end and within the channel 2o, a divider or partition 22 is arranged, which is connected to the mold plate 12 by connecting pieces 24 and 26 709884/1032

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connected is. As can be seen from Figure 2, the partition wall 22 extends from a position adjacent the inlet end 16 to a position lying between the inlet end 16 and the outlet end 18 in the channel 2o and has an inner side 28, which slopes outward and downward, and an outer side 3o that is substantially perpendicular to the outlet end 18 and runs parallel to the inner wall 21. Therefore, the partition wall 22 extends from a thicker upper end adjacent the inlet end 16 tapered to a thinner edge 34 between the inlet end 16 and the outlet end 18 and 14 divides the channel 2o adjacent the inlet end 16 into an outer edge part 2oA and a central inner part 2oB.

The mold plate 12 further comprises an L-shaped channel 36 which leads from an inlet 38 to an outlet 4o. A connector 42 is secured in inlet 38 of channel 36 and is for connection to a source of foamed thermoplastic Material (not shown).

In addition to the connection piece 42, the shape 1o is through a Chuck 44 (see FIG. 2) is attached to the extrusion device 46 and by a bridge 48. Bridge 48 is general M-shaped and has a channel 5o in the shape of an inverted U for connecting the central inner part 2oB of the channel 2o with the L-shaped channel 36 when the bridge 48 is attached to the mold 1o by bolts 5o and 52 through openings 54 and 56 in the Bridge 48 is fastened in corresponding bores 58 and 6o of the mold plate 12. Therefore, spaces 62 and 64 are of the M-shape Bridge 48 arranged over parts of the outer edge portion 2oA of the channel 2o.

The chuck 44 connects the mold 1o to the extrusion device 46 (only a part of which is shown in FIG. 2) and

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sits side walls 66, which surround a channel 68 of sufficiently large dimensions that the bridge 48 receive it can. The chuck 44 is at the inlet end 16 of the mold 1o at one end and at the pipe end 7o of the extruder 46 by one Spindle head 72 attached. The pipe end 7o has a channel 74 aligned with the channel 68 of the chuck 44 a grate-shaped shield 76 for controlling back pressure and keeping contaminants out.

After the chuck 44, the bridge 48 and the mold 1o are joined together, it becomes a thermoplastic in operation Sheath-forming PVC from extruder 46 through channel 74 via shield 76 into channel 68 of liner 44 into the openings 62 and 64 in the m-shaped bridge 48 and then into the outer edge part 20A which forms the envelope of the channel 2o and passed through the form 1o. Practically at the same time is a core-forming foamed PVC from an extruder, not shown, through the connector 42, the L-shaped channel 36, the channel 5o and guided into the inner part 2oB of the channel 2o. While the core-forming foamed PVC moves through the channel 2oB, it can move due to the partition 22 and in particular due to the inclined Expand inside 28 until it merges with the outer layer passing through channel 2oA at the end of the Partition 22 is guided where the foamed PVC exerts a radially outward force against the outer coating exercises that withstand this force.

According to Figure 6, the same devices are used as in Figure 1, only a pin 78 is through a Opening 8o in the m-shaped bridge 48 into the channel 5o and through the part 2oB of the channel 2o under the outlet end

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"ti"

arranged. The mode of operation is the same as in FIG. 2.

In Figure 3 is an extruded profile with a circular cross-section and relatively thin outer layer 8o of PVC and a foamed PVC core 82 shown, which are in intimate compression sealing engagement against the inner wall 84 of the thin outer layer 8o is expanded in that one the foamed material can be expanded radially outward against the inner wall 84 during the extrusion, which thereby exerts a radially outward force against the wall 84 which the layer 8o withstands so that a more uniform Molded body results. The extruded profile of Figure 5 differs from that of Figure 3 in that that the core 82 has a bore 86.

The extruded profile of Figure 4 is made according to Figure 2, but with the side wall 21, the channel 2o surrounds, and the partition wall 22 has a corresponding shape.

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Claims (1)

Claims 1. Extruded profile, characterized by a foamed thermoplastic core (82) surrounded by an outer thermoplastic coating (84) with a predetermined cross-section surrounded with the foamed thermoplastic core (84) in intimate compressed engagement against the Inner wall (84) of the outer layer (8o) during the simultaneous extrusion of the core and the outer layer is expanded, the foamed material being expanded against the outer layer during extrusion and exerting an outward force against the outer layer which the outer layer resists. 2. Profile according to claim 1, characterized in that the outer layer (8o) is relatively thin. 3. Profile according to claim 1 or 2, characterized in that the outer layer consists of hard PVC. 4. Profile according to claim 1, characterized in that the foamed core consists of foamed PVC. Process for the production of an extruded profile, characterized by the following steps: a. substantially simultaneous separate supply of fluid foamed thermoplastic material to the Production of the core and fluid thermoplastic material for the production of the coating in a separate one middle or edge section of a channel with the desired cross-section through an extrusion mold 70988Λ / 1032 adjacent to the inlet of the channel and b. Fusing the coating and the foamed core between the inlet and the outlet, which is called the cellular core material can expand and so an outward force against the outer coating exercises. 6. The method according to claim 5, characterized in that a wall is arranged in the inlet and the middle and separates the edge portion and ends between the inlet and the outlet and the formation of a coating before the Allows fusion with the foamed core material. 7. The method according to claim 6, characterized in that the wall is of uniform thickness, while the Outside of the wall runs parallel to the wall that forms the channel. 8. The method according to claim 6, characterized in that the inside of the wall is adjacent to the central part of the channel outwards to the edge part from the entrance to a position between the entrance and the exit is inclined. 9. The method according to claim 6, characterized in that the wall has a thicker portion adjacent the entrance which has a thinner section approximately in the middle between the inlet and the outlet, so that the inside adjacent the central part of the channel outwards to the edge part of the channel from the entrance is inclined to the position between the entrance and the exit. 709884/1032 273286b - vt - 10. A method for producing an extruded profile, characterized by the following steps: a. substantially simultaneous separate supply of fluid foamed thermoplastic material to the Production of the core and of fluid thermoplastic material for the production of the coating in a separate middle or edge section of a channel with the desired cross-section through an extrusion mold adjacent to the inlet of the channel and b. that you can expand the cellular foamed material evenly when it is through the Channel of the mold moved to the exit. 11. The method according to claim 1o, characterized in that the uniform expansion of the foamed material is accompanied by a gradual increase in the cross-section of the central area of the mold, wherein the foamed material moves from the entrance to the position between the entrance and exit, by one allow uniform expansion. 12. The method according to claim 1o, characterized in that the uniform expansion of the foamed core material is associated with the use of a wall that separates the middle and edge ta.1 in the inlet, wherein the wall ends in a position between the entrance and the exit, the coating and the expanded core material fuses while its inside outwardly adjacent to the central part inclined towards the edge part from the entrance to the exit and the outside of the wall parallel to the edge part outside bounding wall runs. 709884/1032 13. The method according to claim 12, characterized in that the wall has the same cross-section as the channel. 14. Mold for an extruder, characterized by inlet devices for the separate introduction of foamed Core material and coating material in separate parts of the mold to form the core and the coating, wherein the portion for forming the core is within the portion for forming the coating exit means is arranged, while a wall (22) is arranged between the two separate parts of the mold (1o) which ends between the inlet (16) and the outlet (18), in order to fuse the coating part with the foamed core material, the foamed core material engaging with the coating expands. 15. Mold for an extruder, characterized by means for supplying foamed core material and coating material in a separate manner in separate sections of the mold for forming a core and a coating, wherein the portion for forming the core is within the portion for forming the coating exit means and a wall (22) is arranged within the mold (1o) which divides the mold into two sections, the end between the inlet and the outlet to a controlled cell expansion of the foamed core material to allow for fusing with the coating. 16. Form according to claim 15, characterized in that the Inside of the wall (22), which is in contact with the core material, in the region of the core-forming section is tapered from the entry end to the exit end 709884/1032 and terminates in a position between the entry and exit ends. 17. Component for use in an extruder, marked by a front and a rear side as well as a Channel through it, the front side having an inlet for feeding foamed core material into one middle part of the channel and a separate inlet, which is the first inlet to the separate While supplying coating material in an edge portion of the channel to form a coating surrounds the back has an outlet, a partition between the two inlets, extending from one position in the channel adjacent the front to a position in the channel between the front and back extends with the inside of the partition wall outwards towards the edge portion and downwards from the entrance is inclined to allow controlled cell expansion of the foamed material when the foamed Material is moved through the central part of the channel to produce a controlled fusion with the essentially to allow simultaneously extruded coating material approximately in the middle of the component. 18. Component according to claim 17, characterized in that the outside of the partition (22) runs parallel to the surface which delimits the outer edge part. 19. Mold for an extruder, characterized by an opening, which extends from an entry end to an exit end of the mold and the shape of which corresponds to the outer circumference of the final product, with a partition (22) in the opening for dividing the opening 709884/1032 - 1-5- - in two parts, an outer edge part which surrounds an inner part, is arranged, wherein the partition wall is in the opening extends and ends approximately in the middle between the inlet and the outlet end and their Inside is inclined outwards and directed towards the outlet end, around the inner part with a continuous itself to provide enlarged cross-sectional area from the inlet end to the end of the partition. 20. Form according to claim 19, characterized in that the The shape of the partition (22) corresponds to the shape of the opening in the form (lo). 21. Form according to claim 19, characterized in that for feeding thermoplastic material to the mold (1o) means for continuously feeding a coating forming material in the outer edge part of the mold and means for the continuous supply of foamed material forming a core are provided through the inner opening, with a continuous controlled uniform expansion of the foamed core material through the partition wall (22) to the controlled Fusing of the two materials occurs adjacent to the end of the partition. 22. Form according to claim 21, characterized in that separate inlet channels from separate sources for the two materials are provided, the material forming the coating being the outer edge part of the Opening in the mold and the material forming the core is fed to the inner part of the opening. 709884/1032