EP0472072B1 - Wire link-belt - Google Patents

Abstract

A wire-link belt 1, 41 comprises a first and second, opposite belt side 32, 34; 61, 64, the first side supporting a moving length of material or a web of paper 33, 62, said wire-link belt further comprising a plurality of interlinking wire coils 2, 3, 4, 5; 42,43 consisting alternatingly of end arcs 16, 17, 18, 19; 49, 50 and coil-turn legs 10, 11, 12, 13, 14, 15; 45, 46, 47, 48 connecting them and coupled in hinging manner by means of slip-through wires. To reduce slippage between the moving length of material or web of paper 33, 62 and the wire-link belt 1, 41 on one hand and buckling or elongation of said length of material on the other hand, the support of the wire coils 2, 3, 4, 5; 42, 43 at the slip-through wires is such that the wire coils 2, 3, 4, 5; 42, 43 each hinge about axes offset relative to the center plane of the wire-link belt 1, 41 towards its first belt side 32, 61.

Description

The invention relates to a wire link belt, in particular as a paper machine clothing, with a first, intended for the support of a web to be transported and a second, facing away from the band side, the wire link belt having a plurality of juxtaposed, intermeshed wire coils, which alternately consist of head bends and each connecting turn legs exist and are hinge-like coupled via plug wires.

Suggestions have been made at a very early stage to use wire link belts of this type as coverings for paper machines in order to guide and support the paper web through the paper machine. However, a wire link belt that can be used for paper machines was only created by the invention according to DE-OS 24 19 751. Such wire link belts are assembled from a plurality of wire coils made of heat-fixable plastic which are arranged next to one another in the running direction and extend transversely to the running direction by inserting the turns of a wire coil with their head bends into the gaps between the turns of the wire coil already attached to a piece of tape, the overlap is produced in such a way that a channel enclosed by head arches is formed, through which a plug-in wire is pushed for coupling the adjacent wire coils. In this way, an endless wire link belt can be produced which is characterized by good adaptability because of the hinge mobility between the adjacent wire coils.

The wire of a wire helix basically has a helical course, whereby the pitch can be quite different within one turn. In order to achieve a smooth surface, the wire coils on most wire link belts are flattened. In this way, straight stretch legs are formed on the flat, i.e. first and second band sides of the wire link band, which each connect two head arches. As a rule, the adjacent wire coils overlap with their head arches and loop around the plug wire running there.

Deviating from the basic type known from DE-OS 24 19 751, double wire helices can also be used in wire link belts, as they result from EP-A-0̸116,894. In these wire link belts, the turns are wrapped helically around two wire coils arranged next to one another in such a way that plug-in wires are not required there, but only for connecting the double wire coils. In this way, half of the plug wires can be omitted.

EP-A-0̸0̸18 20̸0̸ wire link tapes of various embodiments are disclosed. In this way, wire link belts can also be formed in two layers, the layers being connected by means of additional wire coils that wrap around both layers. This document also shows wire helixes which each extend over three adjacent plug wires and in which two adjacent wire helices overlap each other over two plug wires. From this publication it is also known to couple the adjacent wire coils with more than two plug wires.

To reduce the air permeability, it is proposed in EP-A-0̸ 128 436 and EP-A-0̸ 0̸50̸ 374 to introduce filler material into the cavities enclosed by the winding legs. Another attempt at air permeability To reduce the wire link band consists in flattening the winding legs at least on the side facing the paper web, ie making them wider than in the area of the head bends and thereby narrowing the spaces between the winding legs (cf. DE-PS 32 43 513).

In addition, it is known to provide such wire link belts with an additional layer at least on the side facing the paper web, for example in the form of a needled or glued-on nonwoven fabric (cf. DE-OS 24 19 751, FIG. 3, in the form of a fabric (cf. EP -B-0̸ 0̸80̸ 713) or in the form of perforated foils (cf. EP-B 0̸ 211 471) These additional layers are intended to produce a more uniform surface and additionally reduce the air permeability to a desired value.

The aforementioned wire link belts are sometimes very strongly deflected, in particular when used in a paper machine, when they run over guide rollers or drying cylinders. With each deflection process, the individual wire coils hinge around the connecting wires that connect them and are circular in cross section, the pivot axis being in the central axis of the connecting wires. This leads to a relative movement between the paper web and the wire link belt at their contact surfaces, partly connected with an expansion or compression of the paper web. This is undesirable in the production of high-quality and dust-free paper webs and, in extreme cases, can also result in web damage, especially when guided around said guide rollers.

In order to keep the influence described above low, the wire link belts are made as thin as possible, which can be achieved, for example, with the use of flat wires for the wire helices (cf. DE-PS 34 0̸2 620̸). There are limits to reducing the wire link strip strength, particularly with regard to strength requirements. Corresponding movements on contact surfaces between the paper web can be made accordingly and avoid the first side of the wire link belt.

The invention has for its object to design a wire link belt of the type mentioned so that a sliding movement between the web to be transported, in particular paper web, and the wire link belt and a compression or stretching of the same is reduced, without this particular to the thickness of the wire link belt Must be taken into account.

According to the basic idea of the invention, this object is achieved in that the support of the wire coils on the plug wires is designed such that the wire coils each pivot about hinge axes which are displaced with respect to the central plane of the wire link belt towards its first band side. Due to the inventive displacement of the hinge axes in the direction of the contact surface between the spell to be transported and the wire link belt, the relative movement of the wire link belt relative to the web is reduced when the wire helices are pivoted, and the more the smaller the distance between the hinge axes and the contact surface. In this way, upsetting or stretching as well as roughening of the web are largely or completely avoided. No special consideration has to be given to the thickness of the wire link belt. d. H. In this respect, it can be optimally designed according to the respective requirements.

The basic idea of the invention can be put into practice in different ways. In one possible embodiment, the plug-in wires each have two support edges which run parallel to one another in the longitudinal direction and against which the winding legs forming the first flat side rest, with free spaces in each case between the plug-in wire, the head bow and the winding legs forming the second band side. which allow the wire coils to pivot around one of the support edges. In this embodiment, the plug wires with two support edges lie on the first band side forming turn legs. When the wire link belt is deflected, the adjacent wire coils then each pivot around the support edge near the head arch. Since the support edges are considerably closer to the first flat side than the central axes of the plug-in wires, this has a significant reduction in the relative movement between the web to be transported and the first belt side.

The plug-in wires should preferably have a surface parallel to the underside of the adjacent winding legs between the two support edges, so that there is good support in this respect with a straight course of the wire link belt. The cross section of the plug-in wires should taper in the direction of the turn leg forming the second hinge side in order not to hinder the pivoting movement around the supporting edges or not significantly. Additional free spaces can be obtained in that the head arches are bulged on the inside in such a way that between the plug wires and the head arches there is increasing free space from the support edge near the head bend in the direction of the winding leg forming the second band side. Finally, it is recommended that the inside of the turn legs forming the second band side and the adjacent region of the plug wires are matched to one another in such a way that the plug wires remain in contact with these turn legs when the wire coils are pivoted to one another, apart from one which is present in most cases Game. This ensures optimal guidance of the wire coils with respect to the plug wires when pivoting.

The basic idea of the invention can also be realized in such a way that the plug wires and the transition regions of the turn legs forming the second band side to the head arches abut one another on supporting arches, the radius centers of which lie on the side of the median plane of the wire link band remote from the supporting arches, and in each case between the plug wire, the head arches and the one forming the first side of the tape There are free spaces in the winding legs that allow the wire coils to pivot relative to the plug wires by sliding movement on the support arches around the center of the radius. In this embodiment, the aforementioned transition areas and the plug wires form bearing shell-shaped support arches, the radii of which extend beyond the central axis of the plug wires in the direction of the first band side. In this way, the pivot axis coinciding with the radius centers lies close to the first hinge side and can even be placed in the plane of the first hinge side, depending on the design of the support arches. In this case there is practically no relative movement between the first side of the band and the web to be transported when the wire link belt is deflected. Clearances ensure that the pivoting movement on the support arches is not hindered within a desired pivoting angle.

The plug wires and the wire coils expediently abut one another via supporting arches which are complementary to one another, so that at least one linear support is provided by the mutually adapted course of the contact between the plug wires and the transition region between the top bow and the winding leg.

In order to create sufficient space for the swiveling of the wire coils, the plug wires should taper in cross-section in the direction of the winding leg forming the first band side. On the one hand, this can be done in that the side of the plug wires adjacent to the first band side has a convex contact bend, the radius of the support bends and contact bends being the same. A lenticular or oval cross section is then appropriate. On the other hand, the sides of the plug wires adjacent to the first band side can have a triangular cross-section, forming an abutting edge.

Incidentally, with the wire link belt according to the invention, basically all of the prior art can be used for conventional ones Realize wire link belts known embodiments. Thus, the invention is not subject to any restrictions with regard to the cross-sectional shape of the wires of the wire coils, ie flat wires can be used and wire shapes can also be realized, as they result from DE-PS 32 43 512 and EP-A-0̸ 211 471. Basically, multi-layer embodiments can also be implemented, similarly as can be found in EP-A-0̸0̸18 20̸0̸. As a material for the wire coils and plug wires are mainly thermoset plastics, for. B. polyamides or polyesters.

Furthermore, the wire link belt according to the invention can also be provided with a support in the form of a nonwoven fabric, fabric or a film (cf. DE-OS 24 19 751; EP-A-0̸ 0̸80̸ 713; EP-A-0̸ 211 471). If necessary, it is also not excluded to include additional filling material in the spaces of the wire link belt that are still free, for example in the form of foams, textile threads or profiled wires.

Figur (1)

eine Draufsicht auf ein erfindungsgemäßes Drahtgliederband;

Figur (2)

eine teilweise Seitenansicht des Drahtgliederbandes gemäß Figur (1);

Figur (3)

eine teilweise Seitenansicht eines anderen Drahtgliederbandes und

In the drawing, the invention is illustrated in more detail using exemplary embodiments. Show it:

Figure (1)

a plan view of an inventive wire link belt;

Figure (2)

a partial side view of the wire link belt according to Figure (1);

Figure (3)

a partial side view of another wire link belt and

The wire link belt (1) shown in detail in FIG. (1) has a longitudinal extension in the direction of a double arrow (A), in which it also rotates in a machine, for example a paper machine. It is endless in this direction. In the transverse direction it has a specific, the respective requirements adjusted width.

The wire link belt (1) has a multiplicity of wire helices (2, 3, 4, 5) which are arranged next to one another in the longitudinal direction (A) and extend axially in the transverse direction, with one wire helix (2, 4) alternating clockwise and one wire helix (3 , 5) are wound left-handed. In each case, two adjacent wire coils (2, 3, 4, 5) are inserted into one another with a gap so that they overlap and each form a channel extending in the transverse direction. Plug wires (6, 7, 8) are inserted into the channels, all plug wires (6, 7, 8) extending over the entire width of the wire link belt (1). The plug wires (6, 7, 8) practically form hinge joints between two adjacent wire coils (2, 3, 4, 5).

A cover strip (9) is inserted into the wire coil (4), specifically in the channel enclosed by the windings of this wire coil (4). As a result, the air permeability is reduced transversely to the plane of the wire link belt (1).

Figure (2) shows an enlarged side view of a detail of the wire link belt (1) with the wire helices (2, 3, 4) and the plug wires (6, 7). The turns of the wire helices (2, 3, 4) each consist of straight, upper-sided turn legs (10̸, 11, 12) and also straight, lower-sided turn legs (13, 14, 15), the ends of the turn legs (10̸, 11 , 12, 13, 14, 15) are alternately connected to one another via left-hand and right-hand headers (16, 17, 18, 19). As can be seen from FIG. (1), the wire coil (2) - viewed from the bottom upwards - is initially followed by an underside turn leg (14), a left-hand head bend (16), an upper-side turn leg (11) and a right-hand head bend ( 19) on top of each other. The winding legs (10̸, 13) and the head bow (18) belong to the wire helix (2), while the head bow (179 and Winding legs (12, 15) are part of the wire helix (13).

The head arches (16, 17, 18, 19) are not - as is known in the prior art - semicircular, although this would also be possible for the wire link belt (1) shown here. They each go obliquely downwards to the lower turn legs (13, 14, 15), each directed outwards, so that the lower turn legs (13, 14, 15) are correspondingly longer than the upper turn legs (10̸, 11, 12) .

The cross section of the plug wires (6, 7) is not circular - as in the previously known wire link belts. Rather, each plug wire (6, 7) has a flat upper side (20̸, 21) which is delimited on the sides by a left-hand support edge (22, 23) and a right-hand support edge (24, 25). The support edges (22, 23, 24, 25) run parallel to one another over the entire length of the plug wires (6, 7).

The cross-sections of the plug wires (6, 7) taper downwards, once semi-circular (plug wire (6)) and once triangular (plug wire (7)). Due to this design of the plug wires (6, 7) - of course only a single plug wire form is used for a certain wire link band - and in addition the head bends (16, 17, 18, 19) essentially arise between them and the plug wires (6, 7) triangular, left-hand free spaces (28, 29) and right-hand free spaces (30̸, 31), which become wider at the bottom.

The winding legs (10̸, 11, 12) on the top form a first hinge side (32) which is intended for the support of, for example, a paper web (33) - indicated by dashed lines. The lower turn legs (13, 14, 15) define a second hinge side (34).

If the wire link belt (1) around a drying cylinder in the dryer section of a paper machine in contact with the paper web (33) is guided on the heating roller, the first band side (32) is concavely bent. The wire coils (2, 3, 4) swivel around the plug wires (6, 7), the right-hand head bends (18, 19) around the right-hand support edges (24, 25) and the left-hand head bends (16, 17) swivel the left-hand support edges (22, 23). Due to the free spaces (28, 29, 30̸, 31) this pivoting is not hindered.

The pivoting is reversed accordingly when the wire link belt (1) runs with its second belt side (34) over a guide roller. In this case, the first hinge side (32) is convexly bent and consequently pivot the wire helices (2, 3, 4) over the support edges remote from the headbend, i.e. the right-hand headbends (18, 19) over the left-hand support edges (22, 23) and the left-hand head arches (16, 17) over the right-hand support edges (24, 25).

In both cases, the swiveling of the plurality of wire helices (2) takes place in a neutral plane (35) indicated by dash-dotted lines, which runs approximately in the area of the underside of the winding legs (10 (, 11, 12) on the top. In the previously known wire link belts with round plug wires, this neutral plane is located in the middle plane of the wire link belt (1) through which the axes of the plug wires pass. In the wire link belt (1) according to the figures (1) and (2), the neutral plane (35) is shifted closer to the paper web (33), i. H. the distance between paper web (33) and neutral plane (35) is much smaller. Because of this, the relative movement between the paper web (33) and the first band side (32) is also less when the wire link band (1) is deflected. This results in protection of the paper web (33), i.e. it is less compressed or stretched, and the roughening of the contact surface with the first hinge side (32) is also reduced.

A further wire link belt (41) is shown in FIG. (3), restricted to an enlarged side view in the area the coupling of two adjacent wire coils (42, 43). The basic structure of the wire link belt (41) corresponds to that of the wire link belt (1) according to the figures (1) and (2), only that the shape of the wire helices (42, 43) and the plug wires coupling the wire helices (42, 43) , of which only the one plug wire (44) is shown, are different.

Here, too, the turns of the wire coils (42, 43) each consist of straight, upper-sided turn legs (45, 46) and also straight, lower-sided turn legs (47, 48), the ends alternating via left-hand and right-hand head bends (49, 50̸ ) are connected. In the present case, the left-hand head bend (49) belongs to the winding legs (46, 48) of the wire helix (43) and the right-hand head bend (50̸) to the winding leg (45, 47) of the wire helix (42).

The top arches (49, 50̸) - seen from top to bottom - first have a sharp bend (51, 52) downwards and then merge into a quarter-circle arc (53, 54), which is then tangential in the subsequent underside winding leg (47 , 48) expires. The quarter arcs (53, 54) form support arches (55, 56) on the inside for the plug wire (44).

The plug-in wire (44) is symmetrical to the vertical plane and is delimited on the underside by an arch-shaped support arch (57). Its radius is essentially the same as the radii of the support arches (55, 56), so that between the support arches (55, 56, 57) a line contact with wire helixes (42, 43) that are round in cross section or a surface contact with wire helices that are rectangular in cross section ( 42, 43) is given.

On the side facing the winding legs (45, 46) on the upper side, the plug wire (44) is designed in a roof shape in cross section to form a contact edge (58) extending along the plug wire (44). Because of this roof-shaped Design results on both sides of the contact edge (58) triangular-shaped free spaces (59, 60̸) that increase in size towards the outside.

The radius of the support arches (55, 56, 57) is so large that its radius center lies approximately in a plane which is formed by the upper sides of the winding legs (45, 46) on the top and defines a first hinge side (61). This band side (61) is intended for supporting and transporting, for example, a paper web (62). All center points of the radius then lie in a neutral plane (63) indicated by dash-dotted lines, which coincides approximately with the first band side (61).

When the wire link belt (41) is passed around a drying cylinder in contact with the paper web (62) on the drying cylinder, the first belt side (62) is bent concavely. The wire coils (42, 43) then swivel around the respective plug wires (44), the support arches (55, 56) of the head arches (49, 50̸) in the manner of a bearing on the support arch (57) of the plug wire (47) expire. Depending on the radius of the support arches (55, 56, 57), the pivoting takes place about an axis lying in the neutral plane (63). Since this plane (63) lies practically in the plane of the paper web (62), there is no relative movement between the paper web (62) and the band side (61).

This also applies to the reverse case when the wire link belt (41) runs with its lower, second belt side (64) over a guide roller. In this case, the first band side (61) is bent convexly, the pivot axes then also lying in the neutral plane (63) or in the plane of the paper web (62). In both cases, the free spaces (59, 60̸) ensure that the pivoting movements of the wire helices (42, 43) to each other is not hindered within a certain angular range.

Instead of the roof-shaped profile of the top of the plug wire (44) there is the possibility of also designing this upper side as a convex circular arc - indicated by dashed lines in FIG. 3 - the circular arc having the same radius as that of the supporting arches (55, 56, 57). The result is a lenticular cross-section, whereby the edges of the arches that meet laterally can be rounded.

Claims (14)

1. A filamentary element belt (1, 41), particularly as a covering for a paper-making machine, having a first belt face (32; 61) intended to support a web (33, 62) to be conveyed, and a second belt face (34; 64) removed from the first, wherein the filamentary element belt (1, 41) has a plurality of helical filaments (2, 3, 4, 5; 42, 43) disposed side by side, which alternately consist of header ties (16, 17, 18, 19; 49, 50) and winding limbs (10, 11, 12, 13, 14, 15; 45, 46, 47, 48) connecting the latter in each case, and which are coupled in the manner of hinges via coupling filaments, characterised in that the support of the helical filaments (2, 3, 4, 5; 42, 43) on the coupling filaments is formed in such a way that the helical filaments (2, 3, 4, 5; 42, 43) each swivel about hinge axes which are displaced in relation to the central plane of the filamentary element belt (1, 41) towards the first belt face (32, 61) thereof.
2. A filamentary element belt according to claim 1, characterised in that the coupling filaments (6, 7, 8) each have two support edges (22, 24; 23, 25) which run parallel to each other in a longitudinal direction and are seated against the winding limbs (10, 11, 12) forming the first belt face (32), wherein free spaces (28, 29, 30, 31) exist in each case between the coupling filament (6, 7, 8), the header tie (16, 17, 18, 19), and the winding limb (13, 14, 15) forming the second belt face (34), which free spaces permit swivelling of the helical filaments (2, 3, 4, 5) about the support edges (22, 24; 23, 25).
3. A filamentary element belt according to claim 2, characterised in that the coupling filaments (6, 7, 8) each have a surface (20, 21) between the two support edges (22, 24; 23, 25) which is parallel to the underside of the adjacent winding limb (10, 11, 12).
4. A filamentary element belt according to claim 2 or 3, characterised in that the cross-sections of the coupling filaments (6, 7, 8) diminish towards the winding limb (13, 14, 15) forming the second belt face (34).
5. A filamentary element belt according to any one of claims 2 to 4, characterised in that the header ties (16, 17, 18, 19) bulge internally in such a way that a free space (28, 29, 30, 31), which increases from the support edge (22, 23, 24, 25) adjacent to the header tie towards the winding limbs (13, 14, 15) forming the second flat side (34), is present in each case between the coupling filaments (6, 7, 8) and the header ties (16, 17, 18, 19).
6. A filamentary element belt according to any one of claims 2 to 5, characterised in that the insides of the winding limbs (13, 14, 15) forming the second belt face (34) and the region of the coupling filaments (6, 7, 8) adjacent thereto are matched to each other in such a way that the coupling filaments (6, 7, 8) remain in contact with these winding limbs (13, 14, 15) when the helical filaments (2, 3, 4, 5) swivel in relation to each other.
7. A filamentary element belt according to claim 1, characterised in that the coupling filaments (44) and the transition regions from the winding limbs (47, 48) forming the second belt face (64) to the header ties (49, 50) are seated against each other on support curves (55, 56, 57), the centres of radii of which are situated on the side of the central plane of the filamentary element belt (41) remote from the support curves (55, 56, 57), and that free spaces (59, 60) are present between the coupling filament (44), the header ties (49, 50) and the winding limbs (45, 46) forming the first belt face (61), which free spaces permit swivelling of the helical filaments (42, 43) in relation to the coupling filaments (44) by a sliding movement on the support curves (55, 56, 57).
8. A filamentary element belt according to claim 7, characterised in that the centres of radii of the support curves (55, 56, 57) lie in the plane of the first belt face (61) of the filamentary element belt (41).
9. A filamentary element belt according to claim 7 or 8, characterised in that the coupling filaments (44) and the helical filaments (42, 43) are seated against each other via support curves (55, 56, 57) which are complementary to each other.
10. A filamentary element belt according to any one of claims 7 to 9, characterised in that the cross-section of the coupling filaments (44) diminishes towards the winding limbs (45, 46) forming the first belt face (61).
11. A filamentary element belt according to claim 10, characterised in that the side of the coupling filaments (44) adjacent to the first belt face (61) has a convex contact bend.
12. A filamentary element belt according to claim 11, characterised in that the radius of the support curves (55, 56, 57) is equal to that of the contact bends.
13. A filamentary element belt according to claim 12, characterised in that the coupling filaments (44) have a lens-shaped or oval cross-section.
14. A filamentary element belt according to claim 10, characterised in that the sides of the coupling filaments (44) adjacent to the first belt face (61) have a triangular cross-section with the formation of a contact edge (58).

Images