EP0472072A1 - 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 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, coiled wire coils, which alternately consist of head bends and these connecting turn legs exist and are hinge-like coupled via plug wires.

Suggestions were 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 large number of thermally fixable plastic wire helixes arranged next to one another in the running direction and extending transversely to the running direction, by inserting the turns of a wire helix with their head bends into the gaps between the turns of the wire helix 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.

In deviation 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-0 116 894. 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 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-0 018 200 discloses wire link belts of various embodiments. 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.

In order to reduce the air permeability, it is proposed in EP-A-0 128 436 and EP-A-0 050 374 to introduce filler material into the cavities enclosed by the winding legs. Another attempt to reduce the air permeability of a wire link belt is to flatten the winding legs at least on the side facing the paper web, i.e. H. to make wider than in the area of the head arches and thereby narrow 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-0 080 713) or in the form of perforated foils (cf. EP-B 0 211 471) These additional layers are intended to produce a more uniform surface and also to 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, particularly 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 02 620). However, decreasing the wire link tape thickness is limited zen set, especially with regard to strength requirements. Accordingly, relative movements at contact surfaces between the paper web The object of the invention is to design a wire link belt of the type mentioned at the outset in such a way that a sliding movement between the web to be transported, in particular paper web, and the wire link belt as well as compression or stretching of the same is reduced without that special attention must be paid to the thickness of the wire link belt.

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 shifted towards the first plane side of the wire link band with respect to the central plane. Due to the inventive displacement of the hinge axes in the direction of the contact surface between the web to be transported and the wire link band, the relative movement of the wire link band with respect to the web is reduced when the wire coils 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 supporting 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 being provided in each case between the plug-in wire, the head arc 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 against the winding legs forming the first band side. In the event of a deflection of the forming winding leg. When the wire link belt is deflected, the adjacent wire coils then pivot about 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 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 helices are pivoted relative to one another, apart from one that 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 areas of the turn legs forming the second band side to the head arches abut one another on support arches, the radius centers of which lie on the side of the median plane of the wire link band remote from the support arches, and in each case There are free spaces between the plug wire, the head arches and the winding legs forming the first band side, which allow the wire helices 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, when the wire link belt is deflected, there is practically no relative movement between the first belt side and the web to be transported. 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 are expediently located above one another mentary support arches to each other, so that there is at least a linear support by an adapted course of the contact between the plug wires and the transition region between the head bend and the turn 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-in wires adjacent to the first band side can have a triangular cross section with the formation of a contact edge.

Incidentally, all of the embodiments known in the prior art for the conventional wire link belts can basically be realized in the wire link belt according to the invention. Thus, the invention is not subject to any restrictions on the cross-sectional shape of the wires of the wire coils, i.e. H. Flat wires can be used and wire shapes can also be realized, as they result from DE-PS 32 43 512 and EP-A-0 211 471. Basically, multi-layer embodiments can also be implemented, similarly as can be found in EP-A-0 018 200. 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-0 080 713; EP-A-0 211 471). 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) is a plan view of an inventive wire link belt;
• Figure (2) is a partial side view of the wire link belt according to Figure (1
• Figure (3) is 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 certain width that is adapted to the respective requirements.

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 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-side turn legs (10, 11, 12) and also straight, lower-side turn legs (13, 14, 15), the ends of the turn legs (10, 11 , 12, 13, 14, 15) are connected to one another alternately 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 (10, 13) and the head bend (18) belong to the wire helix (2), while the head bend (179 and the winding leg (12, 15) are part of the wire helix (13).

The head arches (16, 17, 18, 19) are not semicircular, as is known in the prior art, 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 (10, 11, 12) .

The cross section of the plug wires (6, 7) is not - as with the previously known wire link belts - circular. Rather, each plug wire (6, 7) has a flat upper side (20, 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 (30, 31), which become wider at the bottom.

The winding legs (10, 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 winding legs (13, 14, 15) on the underside define a second hinge side (34).

When the wire link belt (1) is guided around a drying cylinder in the dryer section of a paper machine with the paper web (33) in contact with the heating roller, the first belt side (32) is bent concavely. The wire coils (2, 3, 4) swivel around the plug wires (6, 7), the right-hand head bends (16, 17) 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, 30, 31) this pivoting is not hindered.

The pivoting is reversed accordingly when the wire link belt (1) runs with its second belt side (17) 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 (16), i.e. it is less compressed or stretched, and the roughening of the contact surface with the first hinge side (15) is also reduced.

A further wire link belt (41) is shown in FIG. (3), specifically restricted to an enlarged side view in the area of 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, 50 ) 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 (50) to the winding leg (45, 47) of the wire helix (42).

The top arches (49, 50) - 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 to the subsequent underside winding leg (47 , 48) expires. The quarter circle arches (53, 54) form support arches (55, 56) on the inside for the plug wire (44).

The plug wire (44) is symmetrical with respect to the vertical plane and is delimited on the underside by a circular 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 top, 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, triangular shapes are formed on both sides of the contact edge (58), each toward the outside increasing open spaces (59, 60).

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 a paper web (62), for example. 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 guided 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 pivot about the respective plug wires (44), the support arches (55, 56) of the head arches (49, 50) 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 convexly bent, 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, 60) ensure that the pivoting movements of the wire helices (42, 43) to one another are not hindered within a certain angular range.

Instead of the roof-shaped profile of the upper side of the plug-in wire (44), it is also possible to design this upper side as a convex circular arc - indicated by dashed lines in FIG. 3 - it being possible for the circular arc to have 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 which meet laterally can be rounded.

Claims (14)

1. wire link belt (1, 41), in particular as paper machine clothing, with a first, for supporting a web to be transported (33, 62) and a second, facing away from the band side (32, 34; 61, 64), the wire link belt (1, 41) has a multiplicity of wire coils (2, 3, 4, 5; 42, 43) which are arranged next to one another and which alternately consist of head bends (16, 17, 18, 19; 49, 50) and winding legs connecting them in each case (10, 11, 12, 13, 14, 15; 45, 46, 47, 48) exist and are hinge-like coupled via plug wires, characterized in that the support of the wire coils (2, 3, 4, 5; 42, 43) is formed on the plug wires in such a way that the wire helices (2, 3, 4, 5; 43, 43) each pivot about hinge axes which are displaced relative to the central plane of the wire link belt (1, 41) towards its first band side (32, 61) are. 2. Wire link belt according to claim 1, characterized in that the plug wires (6, 7, 8) each have two support edges (22, 24; 23, 25) which run parallel to one another in the longitudinal direction and to which the first belt side (32) Forming winding legs (10, 11, 12) lie, with free spaces between the plug wire (6, 7, 8), the head bend (16, 17, 18, 19) and the winding legs (13, 14, 15) forming the second flat side (34) (28, 29, 30, 31) are present, which allow the wire coils (2, 3, 4, 5) to pivot around the supporting edges (22, 24 ,; 23, 25). 3. Wire link belt according to claim 2, characterized in that the plug wires (6, 7, 8) in each case between the two supporting edges (22, 24; 23, 25) a surface parallel to the underside of the adjacent winding legs (10, 11, 12) (20, 21). 4. Wire link belt according to claim 2 or 3, characterized in that the cross section of the plug wires (6, 7, 8) in the direction of the second strip side (34) forming winding legs (13, 14, 15) taper in cross section. 5. Wire link belt according to one of claims 2 to 4, characterized in that the head bends (16, 17, 18, 19) are bulged on the inside such that between plug wires (6, 7, 8) and head bends (16, 17, 18, 19) there is in each case a free space (28, 29, 30, 31) increasing from the support edge (22, 23, 24, 25) near the head arch in the direction of the winding legs (13, 14, 15) forming the second flat side (34). 6. wire link belt according to one of claims 2 to 5, characterized in that the inner sides of the second band side (34) forming winding legs (13, 14, 15) and the adjacent region of the plug wires (6, 7, 8) are adapted to one another in such a way that the plug wires (6, 7, 8) remain in contact with these winding legs (13, 14, 15) when the wire helices (2, 3, 4, 5) are pivoted relative to one another. 7. wire link belt according to claim 1, characterized in that the plug wires (44) and the transition regions of the second band side (64) forming winding legs (47, 48) to the head arches (49, 50) on support arches (55, 56, 57) abut one another, the radius centers of which lie on the side of the median plane of the wire link band (41) remote from the support arches (55, 56, 57), and that between the plug wire (44), head arches (49, 50) and the first band side (61) Winding legs (45, 46) are free spaces (59, 60) which allow the wire coils (42, 43) to pivot relative to the plug wires (44) by sliding movement on the support arches (55, 56, 57) around the center of the radius. 8. wire link belt according to claim 7, characterized in that the radius centers of the support arches (55, 56, 57) lie in the plane of the first band side (61) of the wire link belt (41). 9. wire link belt according to claim 7 or 8, characterized in that the plug wires (44) and the wire helices (42, 43) abut each other via complementary support arches (55, 56, 57). 10. Wire link belt according to one of claims 7 to 9, characterized in that the plug wires (44) taper in cross-section in the direction of the winding leg (45, 46) forming the first belt side (61). 11. Wire link belt according to claim 10, characterized in that the side of the plug wires (44) adjacent to the first belt side (61) has a convex contact arch. 12. Wire link belt according to claim 11, characterized in that the radius of the support arches (55, 56, 57) and the contact arches is the same. 13. Wire link belt according to claim 12, characterized in that the plug wires (44) have a lenticular or oval cross section. 14. Wire link belt according to claim 10, characterized in that the sides of the plug wires (44) adjacent to the first belt side (61) have a triangular cross-section to form a contact edge (58).

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