EP2358939B1 - Paper machine covering and method for the production thereof - Google Patents

Description

The invention relates to a paper machine clothing, in particular a press felt for a paper, board or Tissuemaschine, according to the preamble of patent claim 1 and a method for its production according to the preamble of claim 31.

Paper machine clothing, in particular press felts for paper, board or tissue machines, generally have a basic structure providing the dimensional stability of the felt, which is provided on both sides with one or more nonwoven layers.

In the past, developments of new press felts often succeeded in producing these by modular construction of individual components and replacing woven structures, since woven structures can only be produced with low productivity.

Thus, for example, in the WO89 / 03300 , which shows the state of the art formed from modules produced press felts. In this case, modules are proposed, which are composed of a nonwoven layer connected to a Längsfadengelege, as well as modules that consist of a connected to a nonwoven fabric layer Querfadengelege.

To simplify the production of such modular structured press felts is in the EP1837440A1 Furthermore, it is proposed to produce the tensile load-absorbing longitudinal reinforcement module from a nonwoven layer connected to Längsfadengelege in a winding process and to use the transverse stability to be used transverse reinforcement module of several only on a portion of the length of the press felt extending transverse reinforcement module sections, which in a first manufacturing step also be made over a winding process as the longitudinal reinforcement module and which are cut in a subsequent manufacturing step to width of the produced press felt and oriented with the threads transverse to the Längsfadengelege in the longitudinal direction of the felt are arranged one behind the other. A disadvantage of such transverse reinforcement structures is that they are produced from a longitudinal thread layer, which must be assembled and cut for use as a transverse reinforcement module and is composed of a plurality of individual sections arranged one behind the other in the longitudinal direction of the press felt.

The known modular press felt concepts here consist of longitudinal yarn layers and transverse yarn fabrics, the two fabrics being connected to one another only via a nonwoven fabric layer. The disadvantage of these structures is that such scrims often provide only a very limited internal volume in the press felt. Further, since the longitudinal and the transverse thread loops can move relative to each other, they diverge as they pass through the press nip, which can lead to a further reduction in the internal void volume and therefore a reduction in water absorption capacity.

In press felts with monofilament woven basic structures, there is often the problem of poor anchoring of the fiber fleece layers in the basic structure, since the fibers can often only be poorly anchored to the basic structure formed from the smooth monofilaments during needling.

Furthermore, woven basic structures are often much thicker than scrim due to threading at the crosshairs.

It is the object of the present invention to propose press felts, in which the abovementioned disadvantages no longer occur and which, moreover, are cheaper to produce than the press felts known from the prior art.

The object is achieved by a paper machine clothing, in particular press felt for a paper, board or tissue machine, with a load-absorbing basic structure which extends in the longitudinal and transverse direction of the fabric and which is formed from a dimensional stability in the longitudinal direction of the fabric substantially providing longitudinal reinforcement module and from a dimensional stability in the transverse direction of the fabric at least partially providing transverse reinforcement module, wherein the transverse reinforcement module and the longitudinal reinforcement module are arranged and connected to each other.

The invention is characterized in that the transverse reinforcement module is formed from at least one warp knit formed from at least one system of weft threads extending parallel to each other in length and at least one system of sewing threads forming stitches substantially perpendicular to the longitudinal extent of the weft threads in which the weft threads are integrated to form a textile fabric, wherein the weft threads extend obliquely in their length, in particular transversely, to the longitudinal direction of the fabric and have a greater flexural rigidity than the sewing threads.

For the purposes of the invention, the longitudinal reinforcement module and the transverse reinforcement module are produced here independently of one another. For the purposes of the invention, the dimensional stability of the fabric in its longitudinal direction is essentially provided by the longitudinal reinforcement module. Furthermore, the dimensional stability of the fabric in its transverse or width direction is at least partially provided by the transverse reinforcement module.

By the term "that the dimensional stability of the fabric in the longitudinal direction of the fabric is provided essentially by the longitudinal reinforcement module" is to be understood that more than 50% of the longitudinal stability of the fabric is provided by the longitudinal reinforcement module. It is also closed note that the longitudinal reinforcement module may also partially contribute to providing the dimensional stability of the fabric in the transverse or width direction of the fabric.

By the term "that the dimensional stability of the clothing in the transverse direction of the clothing is at least partially provided by the transverse reinforcement module" is to be understood that at least a part of the transverse stability of the clothing is provided by the transverse reinforcement module.

In this case, a textile fabric is to be understood as meaning a self-supporting textile structure which is of planar design, i. whose length and width is significantly greater than its height. It is conceivable in this connection that the width and length are greater than the height by more than a factor of 100, in particular by more than a factor of 1000.

The modular paper machine clothing according to the invention has a transverse reinforcement module which at least partially provides the transverse rigidity of the clothing. The transverse reinforcement module is constructed from at least one warp knit, which in turn is constructed from at least one weft thread system and from at least one stitch-forming thread system. Here, the warp knitted fabric is arranged such that the weft threads extend obliquely, in particular transversely, to the longitudinal direction of the fabric. The transverse rigidity of the transverse reinforcement module is essentially or almost completely provided by the weft threads, whereas the stitching threads forming stitches serve essentially only to hold the weft threads in position during the production of the fabric. The warp knit fabric can be produced inexpensively as a flat and one-piece warp knit fabric with any longitudinal extension in the direction of sewing threads by knitting process and subsequently be cut to length, for example, to the length of the papermachine fabric to be produced.

The warp knit fabric can thus be made in any desired length in its longitudinal direction, which is determined by the direction of the sewing threads. Since the warp knit invention can be produced in the direction of its sewing threads in almost any length and extend the dimensionally stable weft threads substantially perpendicular to the sewing threads, a textile structure is provided by the invention, in contrast to that of EP1837440A1 known solution, not to be rotated by 90 ° relative to its longitudinal direction to provide a transverse reinforcement.

The use of a nonwoven fabric for the cross reinforcing module to hold in position a Fadengeleges, as shown in EP1837440A1 known, can be eliminated by the inventive solution.

Furthermore, the solution according to the invention no longer requires a complex weaving process for producing a transverse reinforcement.

Further, since in the transverse reinforcing module according to the invention, the weft threads are incorporated in the stitching threads forming stitches, the distance between adjacent sewing threads can also be made relatively large, without negatively affecting the bond between the weft threads and the sewing threads. Since the threads are not meshed with one another in a woven structure, but are connected to one another only by thread creases, in this case the warp threads and weft threads must be arranged quite close to one another so as not to make the bond between them unstable.

Advantageous embodiments and further developments of the invention are specified in the subclaims.

The transverse reinforcement module may be arranged both on the longitudinal reinforcement module, as it may be arranged below the longitudinal reinforcement module, when in the paper machine clothing, the machine side is considered as down and its paper side as above.

Preferably, the dimensional reinforcement of the fabric in its transverse direction is substantially provided by the transverse reinforcement module. By the term "that the dimensional stability of the fabric in the transverse direction of the fabric is provided essentially by the transverse reinforcement module" is to be understood that more than 50% of the transverse stability of the fabric is provided by the transverse reinforcement module. It is conceivable in this connection that, for example, 70% and more or 85% and more of the transverse stability of the clothing is provided by the transverse reinforcement module.

Preferably, the longitudinal reinforcement module is produced as an endless belt.

In order to further simplify and lower the cost of the basic structure according to the invention, a particularly preferred embodiment of the invention provides that the longitudinal reinforcement module comprises a longitudinal thread loop or is formed by a thread scrim. In this case, it is particularly advantageous for the longitudinal thread layer to be formed from at least one longitudinal thread extending substantially in the longitudinal direction of the clothing and progressively wound helically in the transverse direction of the clothing. Preferably, in this case the at least one longitudinal thread is wound on the width of the basic structure.

If the longitudinal reinforcement module comprises or is formed from a scrim, the dimensional stability of the scrim in the longitudinal direction of the scrim is generally provided by the longitudinal reinforcement module. Furthermore, in this case, the dimensional reinforcement of the fabric in the transverse or width direction of the fabric is substantially provided by the transverse reinforcement module.

If the scrim is formed by only a single longitudinal thread, it extends substantially in the intended longitudinal direction of the felt and can be wound helically progressively in the direction of the intended width of the felt belt to the intended width of the felt. By the helical winding of the longitudinal thread, a Längsfadengelege can be formed, in which each winding of the longitudinal thread extends parallel to the preceding and subsequent winding of the longitudinal thread.

When the longitudinal thread layer is made up of a plurality of longitudinal threads, i. formed from a family of longitudinal threads, so the individual longitudinal threads extend substantially in the intended longitudinal direction of the felt and are juxtaposed in the direction of the intended width of the felt, in this case, the arrangement of the longitudinal threads in the direction of the intended width of the felt belt progressing helical to be wound to the intended width of the felt. By the helical winding of the longitudinal thread arrangement, a Längsfadengelege be formed, in which all longitudinal threads of the arrangement always parallel to each other and in which each winding of each longitudinal thread extends parallel to the preceding and subsequent winding of this longitudinal thread.

In the sense of the present invention, the term that the longitudinal thread (s) extend (s) substantially in the longitudinal direction of the strip should be understood to mean that the longitudinal thread (s) of the longitudinal thread layer and the longitudinal direction of the felt strip together include an angle of a maximum of 10 °, in particular a maximum of 5 °.

According to a further embodiment of the invention, it is provided that the longitudinal reinforcement module is formed by a woven and / or knitted fabric and / or spiral screen and / or knitted fabric. In this case, it is, for example, conceivable that the dimensional stability of the clothing in the longitudinal direction of the clothing is essentially provided by the longitudinal reinforcement module. Furthermore, in this case it is conceivable that in each case by the transverse reinforcement module and by the longitudinal reinforcement module, the dimensional stability of the fabric in the transverse or width direction of the fabric is partially provided. In this case, for example, 50% or more of the dimensional stability of the fabric in its transverse or width direction is provided by the longitudinal reinforcement module and, correspondingly, less than 50% by the transverse reinforcement module.

A development of the invention further provides that the at least one warp knitted fabric is formed from a single system of mutually parallel weft threads and from a single system of stitches forming stitching. This further simplifies the construction of the transverse reinforcement module.

The at least one warp knit fabric is produced in particular by a stitchbonding method in which the weft threads are fed during weft formation by means of weft insertion, in particular by means of parallel weft insertion. During parallel weft insertion, the weft threads are inserted parallel to one another and fixed by the stitches. When Parallelschusseintrag the relative speed between the transport speed of the weft feeder and the transport speed of the transport chain is compensated so that the weft threads come to lie parallel to each other.

The sewing threads also form, in particular, rows of stitches arranged parallel to one another and extending perpendicular to the weft threads, the weft threads being bound into the stitches. The rows of stitches extend in the longitudinal direction of the warp knitted fabric. In this case, the individual courses are in particular not meshed with each other, but merely connected to one another by the weft threads. Preferably, the rows of stitches extend in the longitudinal direction of the fabric.

Further, according to a further embodiment of the invention, it is provided that each sewing thread forms its own row of stitches, wherein in particular each weft thread is bound into a stitch of each stitch row.

In particular, the length of the mesh extending in particular in the longitudinal direction of the fabric is infinitely adjustable within wide limits, for example, preferably in the range between about 0.5 mm and 5.0 mm. Since the weft threads are integrated into the stitches of the sewing threads, the spacing between adjacent weft threads can be varied within further limits, according to the required or desired properties of the transverse reinforcement module and / or the required production output in the production of the transverse reinforcement module without the weft threads being held to vary the sewing threads greatly. A preferred embodiment of the invention therefore provides that the spacing of the weft threads from each other is determined by the length of the stitches in the courses.

Preferably, the distance between adjacent weft threads in the production of warp knitted fabric according to the invention is variable so that this can have a weft thread density in the range of about 40 to 200 threads / 10cm, preferably 80-150 threads / 10cm depending on the required properties.

Furthermore, it is conceivable that the sewing threads are thinner than the weft threads.

For example. to provide a sufficiently high internal void volume, it may be useful if the weft threads are formed by multifilament yarns.

The multifilament yarns can be formed, for example, by twisted monofilament yarns. It is conceivable in this context, for example, that the yarn forming monofilaments of polyamide (PA) are made. Here, for example, 4-ply threads or 10-ply threads as well as all intermediate levels are conceivable.

It is also conceivable to form the weft threads as staple fiber yarns.

The weft threads may also be formed by monofilament yarns. It is conceivable that the weft threads have a round or square cross-section. It is conceivable in the former case that the weft threads have a circular or oval cross-section. In the second case, the weft threads may have a trapezoidal or rectangular cross-section.

In today's seamable press felts with woven basic structure, the longitudinal threads form seam loops. In order to allow passage of a pintle through the seam loops, the longitudinal threads are formed as monofilaments. Furthermore, the transverse threads in such woven basic structures are formed as monofilaments, which is why an anchoring by needling of arranged on the base structure nonwoven layers is often difficult.

By providing the transverse reinforcement module according to the invention in which the weft threads are formed by multifilament yarns, the anchoring of the nonwoven fabric layers to the basic structure can be significantly improved by needling, since the fibers of the nonwoven fabric layer (n) become entangled in the multifilament yarns during the needling process. In addition to the aforementioned multifilaments, the weft threads may also comprise multi-component yarns. In this case, in particular, a component may be made of a material which has a lower melting temperature than the other component (s). It is conceivable, for example, to use as a low-melting component a thermoplastic material such as, for example, PA, PP, or PU, which is melted during a thermal treatment and effects an improved anchoring of the fibers of the nonwoven structure in the basic structure.

It is conceivable, for example, to use PU / PET bicomponent yarns as a multi-component yarn. As a result, a transverse reinforcement structure is produced, which has a high resilience after its compaction in the press nip. Of course it is not necessary that all the weft threads of the warp knit forming the transverse reinforcing structure are multi-component yarns. It is also conceivable to enter multi-component yarns and yarns of other materials alternately. It is also conceivable to enter multi-component yarns simultaneously with yarns of other materials. It is also conceivable to use doubled monofilament yarns, one of the monofilaments being a multicomponent yarn. It is further contemplated that the weft yarns comprise staple fiber yarns, with some of the staple fibers being of a material having a lower melting temperature than other fibers of the yarn.

Furthermore, conceivable as weft yarns contain the PU or are formed from these and to use PA yarns. In this case, for example, it is conceivable to use monofilament yarns of PU and a plurality of monofilament yarns of PA twisted together, for example 4-fold yarns of PA. In the production of the transverse reinforcement module, for example, PU yarns and PA yarns can be alternately entered. It is also conceivable to enter PU yarns and PA yarns at the same time.

In a transverse reinforcement module with PA yarns and PU yarns, the transverse reinforcement is essentially taken over by the PA yarns, the PU yarns essentially providing the resilience and damping properties of the transverse reinforcement module.

The twisted weft threads may have a fineness in the range of about 50-500 tex, especially about 100-400tex. In the sewing threads, for example, a fineness is conceivable which, for example, in the range of about 15-200tex, in particular about 48-120tex, is located.

The sewing threads can be formed as monofilament yarns, as staple fiber yarns or as multifilament yarns.

It is also conceivable that the sewing threads comprise multiple components yarns or are formed from these. The multi-component yarns may in this case comprise a component which has a lower melting temperature than the other component (s). The low melting component may be a hot melt adhesive component which is often a thermoplastic material. It is also conceivable that the sewing threads are made of a material which is lower melting than the materials of the weft threads and the nonwoven structure brought into contact with the basic structure. Through these measures, the anchoring of the fiber fleece structure in the basic structure in conjunction with a thermal treatment can be significantly improved. The thermal treatment can take place here with or without the action of pressure.

In order to increase the internal volume of the press felt, it may also be useful if at least some of the sewing threads are made of a material which can be removed from the material after completion of the paper machine clothing, for example with a solvent. As a possible solvent is, for example, water conceivable.

A further embodiment of the invention provides that changes the density of the sewing threads in the transverse direction of the fabric. It is conceivable, in particular, that the density of the sewing threads in the edge regions of the transverse reinforcement module running along the longitudinal edges of the basic structure is increased with respect to the middle region of the transverse reinforcement module arranged between the two edge regions. For example, it is possible to reduce effects such as "edge flipping" or "edge curl" due to the increased density of the sewing threads in the two edge regions viewed in the transverse direction of the fabric the basic structure can be significantly reduced.

The papermachine clothing according to the invention may, for example, be a press felt which is seamable in the machine. By providing an out At least one warp knit formed transverse reinforcement structure it comes when needling the nonwoven fabric structure to a significantly better anchoring of the nonwoven structure to the basic structure as in press felts with basic structures without knit structure, such as, for example, woven basic structures. As a result, the so-called "peel-back" effect in the seam area can at least be reduced if not completely prevented. If, in addition, hot-melt adhesive fibers are used in the transverse reinforcement module, the connection between the basic structure and the fiber-fleece structure is further improved.

In particular, to further simplify the production of papermachine clothing according to the invention, it may be useful if the warp knitted fabric is made flat.

The term "made flat" in this context is to be understood as a distinction from the terms "endless or round produced". In this case, the warp knit is limited in length by two transverse edges running transversely to the longitudinal direction of the papermachine fabric.

To adjust the warp knit, the warp knit can be cut in its length to about the length of the circumference of the fabric to be produced.

Preferably, the transverse reinforcement module comprises at least one warp knit extending along the length of the fabric. Preferably, the transverse reinforcement module is formed from a single warp knit extending along the length and width of the fabric. For particularly wide clothing, for example, for clothing broader 6-8 meters, it may also be useful if the transverse reinforcement module of several be. two, juxtaposed warp knitted fabric is constructed, which are placed at their mutually facing longitudinal edges on impact and, for example, are interconnected by a connecting strip, which covers the longitudinal edges laid on shock and thus connects the two warp knit together. A preferred Embodiment of the invention therefore provides, the transverse reinforcement module is formed of a plurality of each extending over the length of the fabric and only on a portion of the width of the fabric warp knitted fabric, which are juxtaposed in the transverse direction of the fabric, are arranged together complementary to the width of the fabric.

Alternatively, the transverse reinforcement module can also be formed from a single warp knit having a width smaller than the width of the fabric, which is wound helically progressively extending in the transverse direction of the fabric substantially in the longitudinal direction of the fabric.

The warp knit may be in the form of a roll which is cut to length in accordance with the requirement, for example the length of the fabric to be produced.

To make endless of extending over the length of the string warp, the transverse edges are preferably placed to each other in shock.

Furthermore, the warp knit is made in particular by means of a connecting strip endless by the connecting strip covers the two abutting transverse edges and is connected in the region of the two transverse edges with the warp knit.

Since the cut to the desired length warp knitted at the transverse edges, these present cut edges, tends to frazzle, a preferred embodiment of the invention provides that in the region of at least one of the transverse edges of a strip of material is connected to the warp knit, one edge flush with the Cross edge runs.

Preferably, a fraying of the respective transverse edge preventing material strands is attached to both transverse edges in this context.

In order to reduce the marking tendency of the fabric produced with the material strands and / or connecting strips, the connecting strip and / or the material strip is or are preferably formed from at least one film and / or a spunbonded nonwoven. This may be, for example, a film of polyamide (PA), polyamide copolymer (CoPA), polyethylene terephthalate (PET), polyethylene terephthalate copolymer (CoPET), polyurethane (PU), ethylene vinyl acetate (EVA), polypropylene (PP), thermoplastic polyurethane ( TPU) or polyvinyl acetate (PVA) act. The film may in this case have a basis weight in the range of 10-500 g / m ² , preferably 20-60 g / m ² . Also conceivable are films made of several components, such as PET-PU films, PA-PU films, PET-PA films. Such films may have a basis weight in the range of 20-500 g / m ² , preferably 20-60 g / m ² .

• CoPA, CoPET, PET, low density Polyethylen (LDPE) oder PA. Die Flächenmasse des Spinnvlieses kann hierbei im Bereich von ca. 10g/m²- 150g/m² liegen. Da zumindest bei einem Pressfilz die Grundstruktur bei der Herstellung mit einer oder mit mehreren Faservlieslagen vernadelt ist, ist es im Hinblick auf die Permeabilität der fertig gestellten Bespannung nicht notwendig, dass die Folien permeabel sind. Eine bevorzugte Ausgestaltung sieht daher vor, dass die Folie(n) ursprünglich, d.h. bei der Verbindung mit dem Kettengewirke, impermeabel ist bzw. sind und erst durch einen Vernadelungsprozess permeabel gemacht wurde.

The spunbonded fabric can be formed, for example, from one or more of the following polymers:

• CoPA, CoPET, PET, low density polyethylene (LDPE) or PA. The basis weight of the nonwoven web can in this case in the range of approximately 10 g / m ² - 150g / m ² are. Since, at least in the case of a press felt, the basic structure is needled during production with one or more nonwoven fabric layers, it is not necessary, in view of the permeability of the finished fabric, for the films to be permeable. A preferred embodiment therefore provides that the film (s) originally, ie in the connection with the warp knit, is or are impermeable and only made permeable by a needling process.

The connecting strip and / or the material strip is connected in particular due to the effect of pressure and / or temperature with the warp knit. For this purpose, it is particularly advantageous if the or the connection strip and / or the strip of material melt at a lower temperature than the sewing and weft threads of the warp knitted fabric. It is also conceivable in this connection that the connection strip (s) and / or material strips are connected to one another, for example, by hot-wire welding and / or ultrasonic welding and / or laser welding.

According to a further preferred embodiment of the invention, the longitudinal reinforcement module comprises, in addition to the already described Längsfadengelege arranged on the Längsfadengelege and connected thereto carrier layer. The carrier layer extends in this case, in particular like the longitudinal thread layer, over the entire width and length of the papermachine fabric.

The carrier layer may be formed alone or in combination by: a nonwoven fabric layer, a film layer.

The longitudinal thread layer is preferably embedded in the nonwoven layer. This can be achieved, for example, by needling the longitudinal thread layer with the carrier layer formed as a nonwoven fabric layer. By needling process, it is possible that the carrier layer is thereby largely destroyed. The carrier layer can in this case mainly take on the task of keeping the longitudinal threads of the longitudinal thread fabric during the further manufacturing process of the felt in position.

A concrete development of the invention provides that the transverse reinforcement module is arranged on the support layer of the longitudinal reinforcement module and connected thereto. In this case, the carrier layer, for example, be designed accordingly to be easily connected to the transverse reinforcement module can. It is conceivable, for example, in this context that the nonwoven layer comprises hot melt adhesive fibers, so that the transverse reinforcement module can be bonded to the carrier layer of the longitudinal reinforcement module by the action of heat. Simultaneously with the action of heat, the connection between the transverse reinforcement module and the longitudinal reinforcement module can be further improved by the assistance of pressure. In order to achieve this, it is conceivable, for example, for the longitudinal reinforcement module and the transverse reinforcement module to be jointly guided around a heated roller or through a heated press nip for the purpose of heat action.

Of course, other connection techniques are possible. It is conceivable, for example, that the transverse reinforcement module is connected to the longitudinal reinforcement module by needling them together and / or sewn and / or welded. It is conceivable in this context, for example, that the transverse reinforcement module is made endless and is subsequently connected to an endlessly made or endlessly produced longitudinal reinforcement module and to one or more nonwoven fabric layers in the needle machine by needling. Here, the connection can be made only by needling or in combination with another connection technique.

To further simplify the production of the fabric according to the invention, it is conceivable for the production of the carrier layer to use a prefabricated carrier web with a smaller width than the width of the fabric. In this case, it is conceivable, for example, for the carrier web to be formed from at least one carrier web which extends substantially in the longitudinal direction of the clothing and is wound spirally in the transverse direction of the clothing.

The carrier layer is thus produced in this case by a wound only on a part of the intended width of the paper machine clothing carrier web in the direction of the intended width of the paper machine clothing is wound helically progressively up to the intended width of the fabric.

In helical winding, for example, the mutually facing edges of the carrier web can be placed in abutting or overlapping regions.

1. a) einem sich auf der Breite und der Länge der Bespannung erstreckenden Längsverstärkungsmodul welches umfasst,
   • i) ein Längsfadengelege auf der Breite und der Länge der Bespannung, das gebildet ist aus zumindest einem sich im Wesentlichen in Längsrichtung der Bespannung erstrecken Längsfaden und
   • eine mit dem Längsfadengelege verbundene sich auf der Breite und der Länge der Bespannung erstreckende Trägerlage und/oder
   • ii) ein gewobenes oder spiralisiertes oder gewirktes textiles Flächengebilde, sowie
2. b) einem Querverstärkungsmodul gleicher Länge und Breite wie die Bespannung, wobei das Querverstärkungsmodul und das Längsverstärkungsmodul aufeinander angeordnet und miteinander verbundenen sind, und das Querverstärkungsmodul - durch zumindest ein Kettengewirke gebildet ist, das sich auf der Länge der Bespannung und auf der Breite der Bespannung erstreckt und gebildet ist aus zumindest einem System von sich in ihrer Länge zueinander parallel erstreckenden Schussfäden und zumindest einem im Wesentlichen senkrecht zur Längserstreckung der Schussfäden verlaufenden System aus Nähfäden, die Maschen bilden in welche die Schussfäden zur Ausbildung eines textilen Flächengebildes eingebunden sind, wobei sich die Schussfäden in ihrer Länge quer zur Längsrichtung der Bespannung erstrecken und eine größere Biegesteifigkeit haben als die Nähfäden.

According to a preferred embodiment of the invention, the fabric may comprise a basic structure, which is formed, for example

1. a) a longitudinal reinforcement module extending over the width and the length of the fabric comprising
   • i) a Längsfadengelege on the width and the length of the fabric, which is formed from at least one substantially in the longitudinal direction of the fabric longitudinal thread and
   • a carrier layer connected to the longitudinal thread layer and / or extending over the width and the length of the fabric
   • ii) a woven or spiral or knitted textile fabric, and
2. b) a transverse reinforcement module of the same length and width as the fabric, wherein the transverse reinforcement module and the longitudinal reinforcement module are arranged and interconnected, and the transverse reinforcement module is formed by at least one warp knit extending on the length of the fabric and on the width of the fabric and formed from at least one system of weft threads extending parallel to each other in their length and at least one system of sewing threads extending substantially perpendicular to the longitudinal extent of the weft threads, forming stitches in which the weft threads are integrated to form a textile fabric, the weft threads being extend in length transversely to the longitudinal direction of the fabric and have a greater flexural rigidity than the sewing threads.

It should be noted in this context that the fabric formed as a fabric may be either flat or round woven.

To provide a press felt, it is particularly useful if at least one, in particular a plurality of nonwoven fabric layer (s) is / are arranged on the side of the basic structure of the fabric facing the paper side and / or on the machine side.

1. a) Bereitstellen eines Längsverstärkungsmoduls mit einer Breite und einer Länge, die der Breite und Länge der herzustellenden Bespannung entspricht,
2. b) Bereitstellen eines Querverstärkungsmoduls mit einer Breite und einer Länge, die der Breite und Länge der herzustellenden Bespannung entspricht,
3. c) Anordnen von Längsverstärkungsmodul und Querverstärkungsmodul aufeinander und
4. d) Verbinden des Querverstärkungsmoduls mit dem Längsverstärkungsmodul.

A method for producing the fabric according to the invention, in particular a press felt for a paper machine, which has a length and a width, may comprise the following steps:

1. a) providing a longitudinal reinforcement module having a width and a length corresponding to the width and length of the fabric to be produced,
2. b) providing a transverse reinforcement module having a width and a length corresponding to the width and length of the fabric to be produced,
3. c) arranging longitudinal reinforcement module and transverse reinforcement module on each other and
4. d) connecting the transverse reinforcement module to the longitudinal reinforcement module.

1. i) Bereitstellen zumindest eines Kettengewirkes, das gebildet ist aus zumindest einem System sich zueinander parallel erstreckender Schussfäden und zumindest einem im Wesentlichen senkrecht zur Längserstreckung der Schussfäden verlaufenden System aus Nähfäden, die Maschen bilden in welche die Schussfäden zur Ausbildung eines textilen Flächengebildes eingebunden sind, wobei die Schussfäden eine größere Biegesteifigkeit haben als die Nähfäden und wobei das Kettengewirke eine Länge hat, die der Länge der herzustellenden Bespannung entspricht und
   dass der Schritt c) zumindest den Schritt umfasst;
2. ii) aufeinander Anordnen von Kettengewirke und Längsverstärkungsmodul derart, dass sich die Schussfäden des Kettengewirkes schräg oder quer zur Längsrichtung der Bespannung erstrecken.

The method according to the invention is characterized in that step b) comprises at least the steps;

1. i) providing at least one warp knit formed of at least one system of weft yarns extending parallel to each other and at least one system of sewing yarns extending substantially perpendicular to the longitudinal extent of the weft yarns, forming stitches in which the weft yarns are incorporated to form a fabric; the weft threads have a greater bending stiffness than the sewing threads and wherein the warp knit has a length which corresponds to the length of the fabric to be produced and
   that step c) comprises at least the step;
2. ii) stacking of warp knit fabric and longitudinal reinforcement module such that the weft threads of the warp knit extend obliquely or transversely to the longitudinal direction of the fabric.

If the warp knit originally is longer than the length of the fabric to be produced, then this can be shortened in a further step iii) by cutting the sewing threads of the warp knit fabric to the length of the fabric to be produced.

The order of steps i) -iii) is not specified here. Thus, for example, it is conceivable that first step i) then step ii) and then step iii) is carried out. However, it is also conceivable that step i) is carried out first, then step iii) and, as the last step, step ii).

Thus, it is conceivable that the at least one warp knit fabric providing the transverse reinforcement module is first cut to the length of the fabric before the transverse reinforcement module and the longitudinal reinforcement module are arranged on top of each other. Furthermore, it is therefore also conceivable that the warp knitted fabric, after being arranged on the entire length of the fabric on or under the longitudinal reinforcement module, is cut to the length of the fabric. This can happen, for example, if the warp knit is in the form of a roll and unwound from it during its placement on the longitudinal reinforcement module.

It is also conceivable that the transverse reinforcement module cut to the length of the fabric is first made endless, before it is arranged on the, for example, endlessly made or endlessly produced longitudinal reinforcement module and subsequently connected thereto.

The warp knit fabric and the longitudinal reinforcement module are preferably arranged on top of one another in such a way that the sewing threads extend in the longitudinal direction and the weft threads extending perpendicularly to the latter extend in the transverse direction of the fabric.

After cutting to length, the warp knit fabric can be laminated on each cut edge by means of the material strip already described in order to prevent fraying of the respective transverse edge. Before the subsequent needling, in which one or more non-woven fabric layers are to be needled on the side of the basic structure pointing to the paper side and / or on the machine side, the transverse reinforcement module must be made endless. This can, for example, be done by placing the two transverse edges of the transverse thread module in abutment against one another and connecting them to one another by means of the connection strips already described.

Figur 1

eine Ausführungsform eines erfindungsgemäßen Querverstärkungsmoduls für eine Grundstruktur eines Pressfilzes in Draufsicht;

Figur 2

eine Ausführungsform eines erfindungsgemäßen Pressfilzes mit dem Querverstärkungsmodul der Figur 1 im Querschnitt;

Figur 3

eine Ausführungsform eines erfindungsgemäßen Verfahrens zur Herstellung einer erfindungsgemäßen Papiermaschinenbespannung,

Figur 4

eine alternative Ausführungsform eines erfindungsgemäßen Verfahrens zur Herstellung einer erfindungsgemäßen Papiermaschinenbespannung.

The invention will be explained in more detail with reference to schematic drawings, not to scale. Show it:

FIG. 1

an embodiment of a transverse reinforcing module according to the invention for a basic structure of a press felt in plan view;

FIG. 2

an embodiment of a press felt according to the invention with the transverse reinforcement module of FIG. 1 in cross-section;

FIG. 3

An embodiment of a method according to the invention for producing a papermachine fabric according to the invention,

FIG. 4

an alternative embodiment of a method according to the invention for producing a papermachine fabric according to the invention.

The FIG. 1 shows an embodiment of a transverse reinforcement module 1 according to the invention for a basic structure of a press felt in plan view. The FIG. 1 shows the transverse reinforcement module in sections.

The transverse reinforcement module 1 is formed from at least one warp knit. That in the FIG. 1 shown warp knitted fabric is formed from a system of mutually parallel weft threads 2 and a substantially perpendicular thereto system of stitches forming sewing threads 3. To form a textile fabric, the weft threads 3 are incorporated in stitches 4 of the sewing threads 3.

Furthermore, the weft threads 2 extend in the transverse direction CMD of the clothing and have a greater flexural rigidity than the sewing threads 3. The sewing threads 3 extend in the longitudinal direction MD of the clothing.

The longitudinal direction L of the warp knitted fabric is determined by the longitudinal extent of the sewing threads 3, as the transverse direction Q of the warp knitted fabric is determined by the longitudinal extent of the weft threads 2. Consequently, the warp knit is oriented so as to extend in its longitudinal direction L in the longitudinal direction MD of the fabric.

In the present case, the weft threads 2 are formed by multifilament yarns, for example by four monofilaments of polyamide (PA) twisted together. The twisted weft yarns 2 have a fineness in the range of about 150tex, whereas the sewing yarns have a fineness in the range of about 6.7-14tex.

That in the FIG. 1 shown transverse reinforcement module 1 was prepared by a Nähwirkverfahren in which the weft yarns 2 were fed during stitch formation by means of parallel weft insertion.

As from the representation of FIG. 1 can be seen, form the sewing threads 3 parallel to each other and perpendicular to the weft threads 2 extending rows 5 of 4 mesh, the weft threads 2 are integrated into the mesh 4. In the present case, each of the sewing thread 3 of the system forms its own stitch row 5.

Furthermore, each weft thread 2 is incorporated into a stitch 4 of each stitch row 5.

As from the representation of FIG. 1 can be seen, the distance between the weft threads 2 to each other by the length of the stitches 4 in the courses 5 set.

That in the FIG. 1 shown transverse reinforcement module 1 was made flat.

The FIG. 2 1 shows an embodiment of a papermachine fabric 10 according to the invention in the form of a press felt in cross-section with the transverse reinforcement module 1 of FIG FIG. 1 ,

The fabric 10 has a load-bearing base structure 11 which extends in the longitudinal direction and in the transverse direction CMD of the fabric 10.

In the present case, the basic structure 11 consists of a longitudinal reinforcement module 12 which essentially provides the dimensional stability in the longitudinal direction MD of the clothing 10, and also in the longitudinal reinforcement module 12 FIG. 1 formed, the dimensional stability in the transverse direction CMD of the fabric 10 substantially providing transverse reinforcement module 1, wherein the transverse reinforcement module 1 is arranged on the longitudinal reinforcement module and connected thereto.

That in the FIG. 2 longitudinal reinforcement module 12 shown comprises a Längsfadengelege 13, which is formed of a plurality of substantially longitudinally extending in the longitudinal direction of the fabric 10 and in the transverse direction CMD of the string 10 helically progressively wound longitudinal thread 14.

Furthermore, the longitudinal reinforcement module 12 comprises a carrier layer 15 designed as a nonwoven fabric layer, in which the longitudinal thread layer 13 is embedded.

The nonwoven fabric layer 15 may comprise melt adhesive fibers. In the present case, the transverse reinforcement module 1 is connected to the longitudinal reinforcement module 11 by bonding to the melt fibers, i. the transverse reinforcement module 1 is arranged on the support layer 15 and connected thereto.

Furthermore, in the case of the fabric 10 formed as press felt, two nonwoven fabric layers 17, 18 are arranged on the side of the basic structure 11 facing the paper side 16 and connected to the basic structure 11 by needling. Here, the upper nonwoven fabric layer 17 providing the paper side 16 comprises finer fibers than the middle nonwoven fabric layer 18 arranged between the upper nonwoven fabric layer 17 and the basic structure 11.

Further, in the formed as a press felt covering 10 on the machine side 20 facing side of the base structure 11, a nonwoven fabric layer 19 is arranged, which is connected to the base structure 11 by needling and which provides the machine side 20 of the fabric 10.

The FIG. 3 shows an embodiment of a method according to the invention for producing a papermachine fabric according to the invention.

In the in the FIG. 3a The step shown is an endless trained longitudinal reinforcement module 12, as it is, for example, in the FIG. 2 in that at least one longitudinal thread 14 extending substantially in the longitudinal direction MD of the clothing is helically wound progressively between two rollers 21, 22 which are spaced apart from each other and are aligned in parallel in the transverse direction CMD of the clothing. The length of the longitudinal reinforcement module 12 is determined by the distance of the rollers 21, 22 to each other. The helically progressing winding of the at least a longitudinal thread 14 in the transverse direction CMD takes place up to the desired width of the longitudinal thread fabric. In addition, the longitudinal reinforcement module 12 may comprise a support layer formed as a nonwoven fabric layer 15, in which the scrim is embedded, for example. As a result, a longitudinal reinforcement module 12 is produced which has a width and a length corresponding to the width and length of the fabric to be produced.

In the in the FIG. 3b shown step is, for example, that from the FIG. 1 known transverse reinforcement module 1 is provided by arranging a warp knit forming the transverse reinforcement module 1 on the longitudinal reinforcement module 12 such that the weft threads of the warp knit extend in the transverse direction CMD and the sewing threads extend in the longitudinal direction MD of the fabric to be produced.

Subsequently, the warp knitted fabric is cut in MD and CMD such that the width and the length of the warp knitted fabric corresponds to the width and length of the fabric to be produced.

For cutting the warp knit into MD, the sewing threads of the warp knitted fabric are cut to length such that the length of the warp knit fabric corresponds to the length of the fabric to be produced.

Before cutting the warp knit in the longitudinal direction MD, a material strip 23, 24 is applied to the warp knit in the two areas, with which the cut edges produced subsequently during cutting correspond to the transverse edges, by which the length of the knitted fabric is limited - be laminated against fraying.

In the following in Figure 3c 1, the transverse reinforcement module 1 is made endless by abutting the two cutting edges or transverse edges produced when the fabric is cut to length in its longitudinal direction and joined together by a connecting strip 25 which covers the two transverse edges placed on the joint and is connected to the transverse reinforcement module 1 in the region of the two transverse edges.

For the connection between the longitudinal reinforcement module 12 and the transverse reinforcement module 1, it is conceivable to guide the sandwich of longitudinal reinforcement module 12 and transverse reinforcement module 1 through a heated press nip 28, which is formed from the roller 21 and a, for example, heated counter roll 28, so that the longitudinal reinforcement module 12 and the transverse reinforcement module 1 are connected to each other by the action of pressure and temperature.

After that, the basic structure is finished and can be found in the 3d figure shown step on both sides with one or more nonwoven fabric layers 17, 18, for example. Connected by needling means 27 by needling. For this purpose, it is conceivable to tension the basic structure between two rollers 21 ', 22' spaced parallel to one another and to guide them through the needling device 27.

An alternative possibility for producing a press felt according to the invention is in the Figures 4a-4c shown.

A longitudinal reinforcement module 33 is produced as an endless belt. This may be a like in the FIG. 3a shown Längsfadengelege act or as in the FIG. 4a represented by a fabric formed as a textile fabric which is suitable for substantially providing the longitudinal stability of the fabric. When endless, the fabric 33 can be stretched for this purpose between two mutually parallel spaced rollers 29, 30.

In a further production step, an inventive transverse reinforcement module 1 is provided. For this purpose, a warp knitted fabric is cut to the intended circumferential length of the press felt and, for example, by means of a Foil or spunbond formed connecting strip 25 or made endless by hot wire welding. When endless, the warp knit providing the transverse reinforcement module 1 can be tensioned about two parallel rolls 31, 32.

In the in the Figure 4c The production step shown, the endless longitudinal reinforcement module 33, the endless transverse reinforcement module 1, as well as above and / or below these arranged nonwoven fabric layers 37, 38 are interconnected by needling. For this purpose, the endless longitudinal reinforcement module 33 and the endless transverse reinforcement module 1 are placed on each other by being pulled over two rollers 34, 35 spaced parallel to one another. The longitudinal reinforcement module 33 and the transverse reinforcement module 1 deposited thereon, together with the nonwoven fabric layers 37, 38, are fed to a needling device 36, which needles the entire arrangement of longitudinal reinforcement module 33, transverse reinforcement module 1 and nonwoven fabric layers 37, 38.

Claims (30)

1. Paper machine clothing (10), in particular press felt for a paper, cardboard or tissue machine, having a load-bearing main structure (11) which extends in the longitudinal and transverse direction of the clothing (10) and which comprises, in particular is formed from

   a) a longitudinal reinforcement module (12, 33) that substantially provides dimensional stability in the longitudinal direction of the clothing (10), and

   b) a transverse reinforcement module (1) that at least partially provides dimensional stability in the transverse direction of the clothing (10), wherein the transverse reinforcement module (1) and the longitudinal reinforcement module (12, 33) are arranged one on top of another and are connected together,
   characterized
   in that the transverse reinforcement module (1) is formed from at least one warp knit that is formed from at least one system of weft threads (2) that extend parallel to one another lengthwise and at least one system, extending substantially perpendicularly to the longitudinal extent of the weft threads (2), of sewing threads (3) which form loops (4) into which the weft threads (2) are tied in order to form a textile fabric, wherein the weft threads (2) extend lengthwise in an inclined manner, in particular transversely, to the longitudinal direction of the clothing (10) and have greater flexural rigidity than the sewing threads (3).
2. Paper machine clothing according to Claim 1,
   characterized
   in that the longitudinal reinforcement module (12, 33) comprises a longitudinal cross-laid structure (13) which is formed from at least one longitudinal thread (14) that extends substantially in the longitudinal direction of the clothing (10) and is progressively wound in a helical manner in the transverse direction of the clothing (10).
3. Paper machine clothing according to Claim 1 or 2,
   characterized
   in that the at least one warp knit is formed from a single system of weft threads (2) arranged parallel to one another and a single system of sewing threads (3) forming loops (4).
4. Paper machine clothing according to one of the preceding claims,
   characterized
   in that the transverse reinforcement module (1) is produced by a stitch bonding process in which the weft threads (2) are fed during loop formation by means of weft insertion, in particular parallel weft insertion.
5. Paper machine clothing according to one of the preceding claims,
   characterized
   in that the sewing threads (3) form rows of loops (4) that are arranged parallel to one another and extend perpendicularly to the weft threads (2), and the weft threads (2) are tied into the loops (4).
6. Paper machine clothing according to Claim 5,
   characterized
   in that each sewing thread (3) forms a separate loop row (5).
7. Paper machine clothing according to Claim 5 or 6,
   characterized
   in that each weft thread (2) is tied into a loop (4) of each loop row (5).
8. Paper machine clothing according to one of Claims 6, 7 or 8,
   characterized
   in that the spacing of the weft threads (2) from one another is fixed by the length of the loops (4) in the loop rows (5).
9. Paper machine clothing according to one of the preceding claims,
   characterized
   in that the weft threads (2) are formed by multifilament yarns, in particular by twisted-together monofilaments.
10. Paper machine clothing according to one of the preceding claims,
    characterized
    in that the warp knit is produced in a flat manner.
11. Paper machine clothing according to one of the preceding claims,
    characterized
    in that the transverse reinforcement module (1) comprises a warp knit that extends along the length of the clothing (10).
12. Paper machine clothing according to one of the preceding claims,
    characterized
    in that the transverse reinforcement module (1) is formed from a single warp knit that extends along the length and over the width of the clothing (10).
13. Paper machine clothing according to one of the preceding Claims 1-12,
    characterized
    in that the transverse reinforcement module (1) is formed from a plurality of warp knits that each extend along the length of the clothing (10) and only over a part of the width of the clothing (10), said warp knits being located alongside one another in the transverse direction of the clothing (10) and being arranged in a manner coming together to form the width of the clothing (10).
14. Paper machine clothing according to one of the preceding claims,
    characterized
    in that the warp knit is bounded lengthwise by two transverse peripheries that extend transversely to the longitudinal direction of the paper machine clothing (10).
15. Paper machine clothing according to Claim 14,
    characterized
    in that the transverse peripheries are laid in a manner abutting one another in order to make the warp knit extending along the length of the clothing (10) endless.
16. Paper machine clothing according to Claim 14 or 15,
    characterized
    in that the warp knit is made endless by means of a connecting strip (25) which covers the two transverse peripheries that are laid in a manner abutting one another and is connected to the transverse reinforcement module (1) in the region of the two transverse peripheries.
17. Paper machine clothing according to one of Claims 14-16,
    characterized
    in that a material strip (23, 24) is connected to the warp knit in the region of at least one of the transverse peripheries, one edge of said material strip (23, 24) extending in a manner flush with the transverse periphery.
18. Paper machine clothing according to one of Claims 14-17,
    characterized
    in that the connecting strip (25) and/or the material strip (23, 24) is formed from at least one film and/or a spunbonded fabric.
19. Paper machine clothing according to one of Claims 14-18,
    characterized
    in that the connecting strip (25) and/or the material strip (23, 24) is connected to the warp knit by the action of pressure and/or temperature.
20. Paper machine clothing according to one of the preceding claims,
    characterized
    in that the longitudinal reinforcement module (12, 33) comprises a carrier layer (15) arranged on the longitudinal cross-laid structure (13) and connected thereto.
21. Paper machine clothing according to Claim 20,
    characterized
    in that the carrier layer (15) is formed on its own or in combination by: a fibrous nonwoven layer (17, 18), a film layer.
22. Paper machine clothing according to Claim 21,
    characterized
    in that the longitudinal cross-laid structure (13) is embedded in the carrier layer (15) configured as a fibrous nonwoven layer (17, 18).
23. Paper machine clothing according to Claim 21 or 22,
    characterized
    in that the fibrous nonwoven layer (17, 18) comprises thermally fusible fibres.
24. Paper machine clothing according to one of the preceding claims,
    characterized
    in that the transverse reinforcement module (1) is connected to the longitudinal reinforcement module (12, 33) in that these are adhesively bonded and/or sewn and/or welded together.
25. Paper machine clothing according to one of the preceding claims
    characterized
    in that the transverse reinforcement module (1) is arranged on the carrier layer (15) of the longitudinal reinforcement module (12, 33) and is connected thereto.
26. Paper machine clothing according to one of Claims 21 to 25,
    characterized
    in that the longitudinal cross-laid structure (13) is needled to the carrier layer (15) configured as a fibrous nonwoven layer (17, 18).
27. Paper machine clothing according to one of Claims 20-26,
    characterized
    in that the carrier layer (15) is formed from at least one carrier web that extends substantially in the longitudinal direction of the clothing (10) and is progressively wound in a helical manner in the transverse direction of the clothing (10).
28. Paper machine clothing according to Claim 27,
    characterized
    in that, in the case of helical winding, mutually facing peripheries of the carrier web are laid in a manner abutting one another or in a regionally overlapping manner.
29. Paper machine clothing according to one of the preceding claims,
    characterized
    in that at least one fibrous nonwoven layer (37, 38) is arranged on that side of the main structure (11) of the paper machine clothing (10) that faces the paper side (16) and/or on that side of the main structure (11) of the paper machine clothing (10) that faces the machine side (20).
30. A method for producing a clothing (10), in particular a press felt for a paper, cardboard or tissue machine, which has a length and a width, comprising the following steps of:

    a) providing a longitudinal reinforcement module (12, 33) having a width and a length which correspond to the width and length of the clothing (10) to be produced,

    b) providing a transverse reinforcement module (1) having a width and a length which correspond to the width and length of the clothing (10) to be produced,

    c) arranging the longitudinal reinforcement module (12, 33) and the transverse reinforcement module (1) one on top of the other, and

    d) connecting the transverse reinforcement module (1) to the longitudinal reinforcement module (12, 33),
    characterized
    in that step b) comprises at least the steps of:

    i) providing at least one warp knit that is formed from at least one system of weft threads (2) that extend parallel to one another lengthwise and at least one system, extending substantially perpendicularly to the longitudinal extent of the weft threads (2), of sewing threads (3) which form loops (4) into which the weft threads (2) are tied in order to form a textile fabric, wherein the weft threads (2) have greater flexural rigidity than the sewing threads (3) and wherein the warp knit has a length which corresponds at least to the length of the clothing (10) to be produced, and
    in that step c) comprises at least the step of:

    ii) arranging the warp knit on the longitudinal reinforcement module (12, 33) such that the weft threads (2) of the warp knit extend lengthwise in an inclined manner, in particular transversely, to the longitudinal direction of the clothing (10).

Images