DE2117229A1 - Compressed plastic mesh and process for its manufacture - Google Patents

Description

Registration: Company HETLOK 1IiTEISATIOIiAL LIMITED

Title:

Compressed plastic mesh and process for its manufacture

description

The ~ r'.findun. ;; relates to a pressed plastic net with three Layers of strands, with each layer having a plurality of spaced and parallel strands connected to the :; trMngen an adjacent layer or layers connecting Have crossing points or connection points, and the οtrMnge no layer parallel to the strands of a -other layer are.

It has already been proposed (British patent Eo. 583) to squeeze out plastic nets of this type with a hat head in the form of a hose, which is basically described in British patent 836 555, but which has been modified to include three concentric circular ..'.- jtrizen- LiTrpen, each of which is provided with a plurality of circumferentially spaced outflow openings, which rub the shape of slots or bores, ', the lips are held stationary and the

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the other two lips are rotated relative to it, each the lipnen is responsible for pressing out one of the three previously mentioned strand layers.

In the pending German patent application P 19 07 699.4 a method and a device for pressing a Two-strand plastic net described over a cylindrical mandrel, in which or which is caused that the net hose rotates around the axis of the mandrel as it moves axially, so that each strand of the one strand layer has a fixed one takes a helical course over the mandrel surface, the net tube by means of a cutting device between a pair is divided by adjacent strands of the other layer and the severed continuous web of mesh material thus produced in a direction tangential to the mandrel surface and is withdrawn inclined to the mandrel axis in a line with the helical course. With the withdrawal of the separated iietzbahn the rotation of the squeezed ITetzschlauciies around the

"Causes the mandrel axis.

It is an object of the invention, a method and an apparatus for pressing out a three-strand hose network according to British patent specification 936 588 in such a way that that the hose net can be cut helically in a continuous path by placing the net tube around the mandrel is rotated such that one of the three layers or groups of strands is parallel to the edge of the cut web, a layer forms a right angle with this edge and

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a layer with a predetermined angle, e.g. 45? about the Width of the network is arranged.

Preferably, the strands of the group arranged at an angle or obliquely inclined should be of a smaller caliber than the otrMnge of the other two groups, so that these groups make up the main elements of the network.

In particular, it is also an object of the invention to provide an improved Three-strand IT network in web form to create that through The following stretching is biaxially oriented, with the otrekff occurs in directions that are perpendicular to each other and one of which is parallel to the edges of the web. Preferably, the continuous H.etzbahn should only be in Be stretched lengthways and then across it.

lie invention provides a pressed plastic mesh of the beginning mentioned type with square or rectangular hooks, which is characterized in that all strands are oriented are, the strands of the two outer layers cross at a right angle without being directly connected to each other and the inner and outer strand layers are only coupled together by limited integral intersections or connection points with the third layer of strands, the three layers of strands not having a common junction at any point in the network. The main elements i.e. the strands of the network running at right angles have no mutual connection points, as a result of which.

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what is achieved is that the strands can be oriented substantially uniformly over their longitudinal extent. In this way, there are transition weaknesses between oriented and unoriented sections of the strand and, due to the absence of mutual joints, tear lines between the
two main elements avoided.

In addition, the main elements can move relative to one another and are not immobile by direct connections at their intersections, so that each strand can be diverted.

The invention also provides a method, which is characterized in that a three-strand hose network in three concentric layers, an inner, a middle and a
outer layer, is squeezed out, the squeezed .Netzschlauch is rotated about its axis in such a way that either the inner or the outer strand layer follows a spatially fixed helical course with which the outer or inner strand layer forms a right angle, with the one in between Strands chi ciit with the other strand layers: an angle, e.g. 45, is formed by the agitation tube between a pair of
Strands of the layer that follows the helical course
follows, is severed, the severed continuous mesh web thus formed in a direction tangential to the and
is in line with the angle of the helix of the helical course, is deducted, the continuous lietzbahn a
Subjected to stretching and molecular orientation in a direction parallel to the inner or outer strands

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becomes and finally the monoaxially oriented trajectory of a stretch; and is subjected to molecular orientation in a direction perpendicular to the first stretching and orientation #

Preferably, the continuous Uetzbahn is first in the direction of their longitudinal extension and then stretched transversely to it at a right angle. It is also useful to use the elongated Web immediately prior to transverse stretching of a preheat treatment to subjugate.

In the drawing are preferred embodiments of the invention exemplified and shows

Pig. 1 schematically shows the process steps that follow one another for the production of a biaxially oriented three-strand network with square meshes,

Pig. 2 a Fetζ on an enlarged scale compared to FIG. 2, Fin. * A section through part of a press head for pressing a three-strand network and

FIG. 4 shows a view of the lips of the press head according to FIG. 3 on a smaller scale than in FIG.

A tubular three-strand network 1 has two groups of Strands 2 and 3> which are the main elements of the ITnet and arranged in two layers at right angles to each other are «a third layer of strands 4> which are preferably of a lighter caliber, i.e. thinner diameter than the other severity 2, 3 are * is between the layers of ? and 3 and arranged at an angle of 45 ° to these = »

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net. This hose network 1 is from a Hatrizen head 5 in a Water bath 6 pressed over a cylindrical mandrel 7. The li-open of the die head 5 are described below.

The hose network 8 rotates around the axis of the dome in the direction an arrow 9 so that when the net tube is both in ' Direction of the axis and the circumference of the mandrel ver.schetzt, the strands 2 a fixed helical course around the Follow the mandrel surface.

In this course or this path, a cutter 10, ie, a driven rotating knife, is arranged between two adjacent strands 2, which separates the Hetzschlauch.6jLn a continuous path or a strip 11, which or the pulling means, not shown is deducted at a helix angle of 45 ° and tangential to the mandrel surface «

The shredded web 11 is then led to a stretching device 12 of a known type, which stretches and _{orients the longitudinal strands 2 and thus creates an intermediate product 1a: s} in which the longitudinal strands 2 are full, the cross strands 3 are not and the strands are inclined running Zwiaeheastr / än, ge 4 mur are stretched to one part. Palis a hate this: construction is desired _r then here is an end product

The monoaxially stretched network ta can then directly a cross Be subjected to stretching. If all of them are too strong of each other

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deviating linear working speeds are to be avoided, the net can be rolled into rollers that are used for this can be fed to the transverse stretching device; these The continuous process is interrupted the point 13 indicated.

The monoaxially stretched Hetz 1a then becomes a transverse stretching device 14 supplied per se known design. The network 1 a is preferably preheated in a device 15 before it is stretched transversely.

scrambled eggs AEE :: i now available biaxially stretched ITetz 1b are the previously stretched strands J stretched in the same manner and to the strands 3-oriented as the inclined strands 4. Thus, the quadratmaschige network structure 1, which was originally pressed, its proportions assumed again in a dimensionally corrected and oriented state 1b.

In the biaxially oriented network 1b (see Pig. 2), the longitudinal strands 2 and the transverse strands 3, which represent the main elements of the network, intersect at points _15f at which there is no connection or unification, ie reciprocal linking of the strands . The strands can thus bend and move independently and freely of one another, as indicated by arrows 16. The structure is held together by integral or connecting nodes 17 »18 of the strands 2 with the strands 4 or the strands 3 with the strands 4.

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The hose network, which has three strands, outer, inner and middle, is squeezed out by the die head 5 (s, FIGS. 3 and 4), which has three concentric tilts 20, 21 and 22, known per se, with the circumference spaced outflow openings 25) 26, 27 are provided, which are slit-shaped but can also be shaped as bores the slots 25 and 7.7 out.

In order to ensure that the three-strand mesh hose 8 rotates as desired around the axis of the dome 7, the strands 2 following a fixed helical course around the mandrel axis, the strands 3 extending at a right angle to the strands 2 and the strands 4 are arranged at a 45 ° V / angle to strands 2 and 3, either the inner lip 20 or the outer lip 21 is held stationary, the middle lip is rotated at 3/4 revolutions per minute and the other lip becomes 21 or 20 rotated in the same direction at 2x revolutions per minute. As shown in Fig. 1 and as it is preferred to simplify the die head, the outer lip 21, which squeezes out the strands following the fixed helical course, is stationary, and the middle lip 22, which squeezes out the strands 4, rotates at 3/4 revolutions per minute

and rotates the inner lip 20 expressing the strands 3 at 2χ revolutions per minute.

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Dan biaxially stretched Hetz 1b is parallel and in the direction dimensionally stable at right angles to the edge of the web. Its main elements, the severity 2 and 3, are mutually not mutually exclusive connected and oriented substantially uniformly. This creates tear lines between two groups of main elements and weak points along the length of the strand are avoided. This makes the Hetz particularly suitable between thin webs of material, preferably plastic film or Paper to be laid as reinforcement and stabilizer.

Since the main elements, strands 2 and 3, are not mutually connected and therefore, as previously described, can move and evade relative to each other, the Hetz 1b is suitable as a rough base material for piercing fibers, to make a mushroom or a blanket. The strands can move aside under the needle throat stitch.

To make strands of 4 finer caliber is the cross-sectional area the outflow openings 27 of the lips 22 smaller than those of the outflow openings 25, 26 of the lips 20, 21, from which the main element strands 2 and 3 are pressed out.

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Claims (2)

Claims 1. Pressed plastic mesh with three layers of strands, each layer comprising a plurality of spaced and parallel strands having intersections or junctions with the strands of the adjacent layer or layers, and the strands of no layer parallel to the Strands of another layer are characterized in that all strands (2,3,4) are oriented, the strands (2,3) of the two outer layers cross at right angles without being directly connected to one another and the inner ones and outer strand layers are only coupled to one another by limited integral junctions (17, 18) with the third layer of strands (4), the three layers of strands not having a common connecting point at any point in the network. > r Λ 2.! A method for producing a pressed plastic net according to claim 1, characterized «that a three-strand hose network is pressed out in three concentric layers, an inner, a middle and an outer layer, the pressed-out hose is rotated about its axis in such a way that either the inner or outer strand layer follows a spatially fixed helical course with which the outer or inner layer forms a right angle, the strand layer lying between them forming an angle, for example 45 °, with the other strand layers 10984771170 - 11 -. Mesh tube between a pair of strands of those Layer, which follows the helical course, is separated, the separated continuous ITetzbahn formed in this way in a direction that is tangential to and in line with the angle of the helix of the helical course, deducted becomes, the continuous .Netzbahn of a stretching and molecular orientation in one to the inner or the outer stretching is subjected to a parallel direction and finally monoaxially oriented path of stretching and is subjected to molecular orientation in a direction perpendicular to the first stretch and orientation. 109847/1170 Al Blank page