KR20070019767A - Seam for multiaxial papermaking fabrics - Google Patents

Abstract

A method is disclosed for sewing an on-machine-seamable multiaxial papermaker fabric to prevent yarn migration. The multiaxial fabric 22 is in the form of an endless loop that flattens into two layers 40, 42 along the fold line 38. CD yarns 28 are removed from the fold line 38 to create an extended label area. This leaves MD yarns 26 not tied to the label area. Suture loops 56 are formed from machine direction threads 26 that are not tied to the fold line 38. Cross machine direction materials 82, 84 (ie, continuous cross machine direction yarns) are attached (weaved back into the fabric) along the edges of the label area at each fold line 38. The attached cross-machine direction materials bind the cross machine direction yarn tails along the edges of the label area to prevent the cross machine direction yarn tails from migrating into the seam area.

Multi-Axis, Papermaker's Fabric, Cross Machine Directional Yarn, Machine Directional Yarn, Label Area, Seal Area, Suture Loop

Description

Seam for multiaxial papermaking fabrics

The present invention is directed to sewing multiaxial fabrics on paper machines.

During the papermaking process, a cellulose fibrous web is formed by depositing a fibrous slurry, ie, an aqueous dispersion of cellulose fibers, on a moving forming fabric in the forming section of the paper machine. A large amount of water is then drained from the slurry through the forming fabric, leaving behind a cellulose fiber web on the surface of the forming fabric.

The newly formed cellulose fiber web runs from the forming portion to the press portion comprising a series of press nips. The cellulosic fibrous web passes through the press nips supported by one press fabric or, as is often the case, between two press fabrics. In press nips, the cellulosic fibrous web is pressurized, which forces the water from the web and adheres the cellulose fibers in the web to each other to convert the cellulosic fibrous web into a paper sheet. This water is received by the press fabric or fabrics and ideally does not return to the paper sheet.

The paper sheet finally proceeds to the dryer section, which includes at least one series of rotatable dryer drums or cylinders which are internally heated by steam. The newly formed paper sheet proceeds along a winding path sequentially around each of the series of drums by a dryer fabric that adheres the paper against the surface of the drum. The heated drums reduce the moisture content of the paper sheet to the desired level through evaporation.

It should be appreciated that the forming fabrics, press fabrics and dryer fabrics all take the form of circulation loops in the paper machine and function like a conveyor. It should also be appreciated that the papermaking process is a continuous process that proceeds at a significant speed. That is, even while the newly produced paper is continuously wound onto a roll after exiting the dryer section, the fiber slurry is continuously deposited onto the forming fabric in the forming section.

The present invention relates generally to fabrics used in the press section, commonly known as press fabrics, which are not only used as bases for paper industrial process belts coated with polymers, for example elongated nip press belts, It can be applied to the fabric used in the dryer section.

Press fabrics play a crucial role during the paper manufacturing process. One such role is to support and transport paper products made through press nips, as highlighted above.

Press fabrics contribute to the surface finish of the paper sheet. That is, the press fabrics are designed to have structures that are smooth and evenly elastic so that a smooth, unmarked surface is imposed on the paper during the passage through the press nips.

Most importantly, the press fabric contains a large amount of water extracted from the wet paper in the press nip. In order to fulfill this function, a space must be provided within the press fabric, referred to as void volume, and the fabric must have adequate water permeability for the entire useful life. Finally, the press fabric should be able to prevent the water received from the wet paper from returning to the wet paper and re-wetting as the paper exits the press nip.

Modern press fabrics are manufactured in a variety of styles designed to meet the requirements of papermaking equipment that is fitted to the paper grade to be manufactured. Generally, press fabrics include woven base fabrics that are sewn into batts of fine nonwoven fibrous material. The base fabrics are woven from single, twisted, single, or multi-threaded yarns and take the form of a single layer or multiple layers or laminates. The yarns are extruded from any of several synthetic polymer resins such as polyamide and polyester resins commonly used for this purpose by those skilled in the papermaking garment art.

Woven base fabrics take many different forms. For example, they are either woven in the form of endless fabrics, or converted into endless forms with flat woven and incidentally woven seams. Alternatively, they are usually produced as endless woven fabrics modified by known processes. At this time, the widthwise edges of the base fabric have seaming loops made using its MD yarns. In this process, the machine direction yarns are woven continuously back and forth between the widthwise edges of the fabric and are turned at each edge to form a suture loop. The base fabrics produced in this way take an endless form during installation on paper machines and for this reason are referred to as on-machine-seamable fabrics. In order to place such fabric in an endless form, the two widthwise edges contact each other, the suture loops entangle each other at the two edges, and a suture pin or pintle is passed through a passage defined by the entangled suture loops. .

In addition, the woven base fabrics are laminated by placing one base fabric into an endless loop formed by another fabric and sewing the main fiber batt through both the base fabrics to join the base fabrics and the main fiber batt. One or two woven base fabrics take on-machine-seamable type.

In some cases, the woven base fabrics are in the form of endless loops, sewable in a shape having a specific length when measured in the longitudinal direction and having a specific width when measured in the transverse direction. As paper machine configurations vary, paper machine clothing manufacturers need to manufacture fabrics and belts to dimensions that match specific locations in their paper machines. Needless to say, these requirements make it difficult to streamline the manufacturing process as each fabric must be made to order.

In modern papermaking machines, fabrics have a width of 5 to 33 feet, a length of 40 to 400 feet and a weight of about 100 to 3,000 pounds. These fabrics wear out and require replacement. The replacement of the fabrics requires a stop of the mechanism, such as the removal of the woven fabric, the setting for the installation of the fabric and the installation of a new fabric. Some Paper Industry Process Belts (PIPBs) are contemplated to have a mechanical seal capability, such as some transfer belts known as Transbelt®. Installation of the fabric involves pulling the fabric body over the mechanism and joining the fabric ends to form an endless belt.

In accordance with the need to rapidly and efficiently produce fabrics of various lengths and widths, it is here necessary to manufacture press fabrics using a spiral winding technique as disclosed in US Pat. No. 5,360,656 to Rexfelt et al., Which is incorporated by reference. Recently proposed.

Press fabrics according to US Pat. No. 5,360,656 include a base fabric having one or more layers of major fiber material sewn into the base fabric. The base fabric comprises at least one layer consisting of a spirally wound strip of woven fabric having a width less than the width of the base fabric. The base fabric has an infinite shape in the longitudinal or machine direction. The longitudinal sewing threads of the spirally wound strip are at an angle in the longitudinal direction of the press fabric. Strips of woven fabrics are woven flat on a loom, narrower than those typically used in the manufacture of paper machine clothing.

The base fabric includes a plurality of spirally wound and joined turns of a relatively narrow woven fabric strip. Fabric strips are woven from longitudinal yarns (warp) and transverse yarns (weft). Adjacent turns of the spirally wound fabric are adjacent to each other, and the spiral continuous seams are sewing, stitching, melting, welding (i.e., ultrasonic welding). ) Or by gluing. In contrast, adjacent longitudinal edge portions of the helical turning portions adjoining one another are arranged overlapping as long as they have a reduced thickness so as not to cause an increase in thickness in the overlapping region. In contrast, the space between the longitudinal yarns increases at the edges of the strip, so that the helical turns facing each other are arranged overlapping, creating a space that does not change between the longitudinal yarns in the overlap region.

In all cases, a basic fabric is obtained that takes the form of an endless loop and has an inner face and is woven in the longitudinal (machine) and transverse (cross-machine) directions. Lateral edges of the base fabric are cut out parallel to the longitudinal (machine) direction. The angle between the machine direction of the base fabric and the spirally continuous seams is relatively small, typically less than 10 °. Likewise, the longitudinal threads (warms) of the fabric strip are equally small in angle with respect to the longitudinal direction of the base fabric. Similarly, the wefts of the fabric strip, which are generally perpendicular to the warp yarns, make an equally small angle with respect to the transverse (cross-machine) direction of the base fabric. In the fabric strips, the weft and warp deflect not always perpendicular to each other. In short, the warp and weft of the fabric strip are not aligned with the longitudinal (machine) or transverse (cross-machine) direction of the base fabric.

Press fabrics having such a base fabric are referred to as multiaxial press fabrics. Standard press fabrics according to the prior art have three axes. One is the machine direction (MD), the other is the cross-machine direction (CD), and the last one is the Z direction through the thickness of the fabric. Multiaxial press fabrics have these three axes as well as at least two axes defined by the direction of the yarn systems in a spirally wound layer or layers. There are also multiple flow paths in the Z direction of the multiaxial press fabric. As a result, the multiaxial press fabric has at least five axes. Due to the multiaxial structure, multiaxial press fabrics having more than one layer are pressed against the nesting and / or during the papermaking process as compared to having a base fabric layer with yarn systems parallel to each other. Excellent resistance to collapse in response to compression at.

Until recently, multiaxial press fabrics of the type described above have only been produced in an infinite form. As such, their use has been limited to press sections with cantilevered press rolls and other parts allowing endless press fabric to be installed from the side of the press section. They are easy to manufacture and have an excellent resistance to compaction, which is of increasing interest, and there is an increasing need for multiaxial press fabrics that can be sewn in an infinite fashion during installation in the press section, thereby increasing such presses. Fabrics are useful for use in paper machines without cantilevered parts. On-machine-seamable multiaxial press fabrics developed to meet this need are described in US Pat. No. 5,916,421 to Yook, which is incorporated herein by reference; 5,939,176; And 6,117,274.

U.S. Patent No. 5,916,421 discloses a machine-sewable multiaxial press fabric for the press section of a paper machine, which is assembled by spirally winding a fabric strip in a plurality of adjacent turnings attached adjacent to each other. Made from a layer of fabric The resulting infinite foundation fabric layer is flattened to produce first and second strands that are joined to each other at the overlapped portions in their widthwise edges. The wefts are removed from each turn of the fabric strip at the nested portions in the widthwise edges to create untied sections of the weft. A sealing element having suture loops along one of the widthwise edges is disposed between the first strand and the second strand at each of the nested portions in the two widthwise edges of the flattened base fabric layer. . The suture loops extend outwards between the unstretched sections of the warp from between the first strand and the second strand. The first and second strands are layered on each other by sewing the staple fiber elastic material passing between them. The press fabric is joined indefinitely during installation on the paper machine by passing the pintle through the passage formed by the interdigitation of the suture loops at the two widthwise edges.

U. S. Patent No. 5,939, 176 also discloses on-machine-seamable multiaxial press fabrics. The press fabric is made from a base fabric layer assembled by spirally winding the fabric strip in a plurality of adjacent turnings attached adjacent to each other. The resulting infinite foundation fabric layer is flattened to produce first and second strands that are joined to each other at the overlapped portions in their widthwise edges. Wefts are removed from each turn of the fabric strip at the nested portions in the widthwise edges to create the suture loops. The first and second strands are layered on each other by sewing the staple fiber elastic material passing between them. The press fabric is joined indefinitely during installation on the paper machine by passing the pintle through the passage formed by the interdigitation of the suture loops at the two widthwise edges.

Finally, US Pat. No. 6,117,274 also discloses on-machine-seamable multiaxial press fabrics. The press fabric is made from a base fabric layer assembled by spirally winding the fabric strip in a plurality of adjacent turnings attached adjacent to each other. The resulting infinite foundation fabric layer is flattened to produce first and second strands that are joined to each other at the overlapped portions in their widthwise edges. Wefts are removed from each turn of the fabric strip at the nested portions in the widthwise edges to create untied sections of the warp yarns. Incidentally, the sewable base fabric on the machine with suture loops along the width rims is disposed between the first and second fabric strands of the flattened fabric layer. The suture loops extend outwardly between the untied sections of the warp from between the first and second fabric strands. The first fabric strand, the base fabric sewn on the machine and the second fabric strand are layered on each other by stitching the staple fiber elastic material therebetween. The press fabric is joined indefinitely during installation on the paper machine by passing the pintle through the passage formed by the interdigitation of the suture loops at the two widthwise edges.

Seams are generally a critical part of the sewn fabric, and due to the uniform paper quality, low marking and good runability, seams similar to the rest of the fabric are required for properties such as thickness, strength, permeability, etc. . The sealing area of the workable fabric behaves under load and, like the rest of the fabric, exhibits the same permeability to water and air, thereby preventing periodic markings of the paper product from being made by the sealing area. Despite the considerable technical difficulties encountered by these sealing requirements, it is desirable to develop sewable fabrics because they are relatively easy to install and safe.

As described with reference to US Pat. No. 5,939,176, the CD area of the multiaxial fabric comes out, and the fabric then folds over this area to form a suture loop. The drawback of this solution of seaming in multiaxial fabric structures is that the cross-machine direction tails remain in the suture area. This cross machine direction yarn tail is a function of the cross machine direction yarn angle associated with panel width, fabric length and panel warpage. Such cross-machine direction tails are not fixed into the base fabric and are free to move or "migrate" into the seam area. This problem is known as real migration. When this real migration occurs, the cross-machine direction yarn ends move into the seal area and interfere with the seal (sometimes seriously). In addition, these unthreaded threads do not provide adequate even support for the fibrous elastic material in the sealing region.

Attempts have been made to use certain adhesives to bind these yarns and prevent yarn migration, but with limited success. Therefore, there is a need for the development of improved seams to prevent yarn migration in multiaxial fabrics.

The present invention seeks to provide improved seams for multiaxial fabrics. The method of the present invention provides a solution to the problem of real migration in the sealing area. In addition, the improved seam provides adequate even support for the fiber ball material in the sealing area.

Therefore, it is an object of the present invention to overcome the above mentioned problems when sewing a paper machine fabric.

Accordingly, the present invention relates to a method for sewing a papermaker's fabric and a fabric seam made according to the method.

The present invention is a method of sewing a multiaxial papermaker fabric sewable on a machine. This fabric takes the form of an endless loop that is laid flat into two layers along the first nested portion and the second nested portion. Cross machine direction yarns are removed from the first nested portion and the second nested portion to create label regions. This leaves machine direction yarns untied in the label area. The suture loops are formed from machine direction yarns not tied to the first nested portion and the second nested portion. Cross machine direction yarn materials (ie, continuous cross machine direction yarns) are attached, rewoven, or sewn into the fabric along the edges of the label area at each nested portion. The attached cross machine direction yarn materials act to join the yarn segments along the cross machine direction yarn edges of the label regions. The fabric is sealed by overlapping the suture loops from the first nested portion and the second nested portion with each other and inserting a pintle into the resulting product.

The method further includes weaving at least one additional cross-machine direction yarn into the label area to impart desired properties to the seam area of the fabric. Such additional cross-machine direction yarns are yarn or yarns or string materials, such as those disclosed in US Pat. No. 5,476,123, referred to as Albany International's trade name "Circumfles." The attached cross-machine direction yarn material is made of a yarn having a pre-attached layer of heat-fusible cover or heat-fusible yarn or a braided yarn of heat-fusible material. The diameter of the attached cross machine direction yarn material is smaller than the diameter of the cross machine direction yarn in the fabric, thereby reducing the plane difference in the seam. In addition, the label area is made wider than normal to accommodate the attached cross-machine direction yarn material woven again in the suture loops.

According to another embodiment of the present invention, the yarns of the fabric are at an angle to the cross machine direction yarns and the machine direction yarns, and some of the yarns removed from the cross machine direction yarns along the edges of the label area have the full width of the fabric. It does not extend across and leaves the yarn and the small segments that are problematic when migrating into the suture loop area completely in the cross machine direction yarn. The fabric is formed from a woven fabric strip having a width less than the width of the fabric, and the lateral edges are formed adjacent or overlapping each other to form spiral seams when the fabric strip is wound in a continuous spiral to form the fabric.

According to another embodiment of the invention, the fabric is a multiaxial press fabric sewable on a machine for the press section of the paper machine. At least one layer of staple fiber batting material is sewn into the fabric. At least some of the yarns are one of polyamide, polyester, polybutylene terephthalate (PBT), or other resin used to form the yarn used in the manufacture of papermaking fabrics. Certain of the yarns have a circular cross-sectional shape, rectangular cross-sectional shape or non-circular cross-sectional shape.

The present invention will become apparent from the following detailed description of the invention with reference to the accompanying drawings.

1 is a plan view of a multiaxial foundation fabric in a flattened state;

2 is a plan view of a portion of the surface of the multiaxial foundation fabric layer;

3 is a schematic cross-sectional view of the flattened base fabric layer shown along lines 6-6 of FIG. 1;

FIG. 4 is a view similar to FIG. 3, showing a schematic cross sectional view along the label area;

FIG. 5 is a view showing a state in which wefts are removed to form a label area, and a plan view of a part of the surface of the base fabric layer shown in FIG. 2; FIG.

FIG. 5A is a top view of a label area in the multiaxial base fabric layer as shown in FIG. 5; FIG.

6 shows a state in which a suture loop is formed along a nested portion, a schematic cross-sectional view of a flattened base fabric;

7 is a view showing a state in which a sealed multiaxial press fabric is installed on a paper machine, a schematic cross-sectional view;

FIG. 8 is a plan view of the seaming area of a closed multiaxial press fabric as shown in FIG. 7; FIG.

9 is a schematic enlarged cross sectional view of a suture loop region of a flattened base fabric;

10 is a schematic enlarged cross-sectional view of a suture loop region of a flattened base fabric, showing a continuous cross machine direction yarn woven back to prevent yarn migration in accordance with the present invention;

FIG. 11 is a plan view of a portion of the surface of the base fabric layer similar to that shown in FIG. 5, showing a state of reweaving a continuous cross machine direction yarn in the label area to prevent yarn migration in accordance with the present invention; FIG.

12 is a plan view of a multiaxial foundation fabric layer having threads sewn into a label area in a zigzag pattern to prevent thread migration in accordance with one embodiment of the present invention;

FIG. 13 is a view showing a thread sewn to cover along a suture rim to prevent thread migration, in accordance with another embodiment of the present invention, a plan view of the suture loop rim of a multiaxial foundation fabric layer; FIG.

14 is a plan view of a suture loop rim of a multiaxial foundation fabric layer having threads sewn into a suture rim in a zigzag pattern to prevent thread migration in accordance with another embodiment of the present invention;

FIG. 15 is a plan view showing a low melting nonwoven layer inserted into a nested area of a multiaxial foundation fabric layer prior to heat setting the suture loops to prevent thread migration in accordance with another embodiment of the present invention; FIG.

FIG. 16 is a plan view of a multiaxial foundation fabric layer having Circumflex yarns sewn into vertical label closure areas and secured in place in a zigzag pattern by fine single thread in accordance with the present invention; FIG.

FIG. 17 is a plan view of a multiaxial foundation fabric layer having Circumflex yarns stitched into a zigzag pattern in place by fine single thread yarns, in accordance with the present invention, into the rim of a vertical label stitching region; FIG.

18 is a plan view of a multiaxial foundation fabric layer having fine fine single thread or micro sheath / core yarns sewn into a vertical label closure region in accordance with the present invention;

19 is a plan view of a multi-axial foundation fabric layer having two different threads sewn into the rim of a vertical label stitching area by two rows of stitching in accordance with the present invention;

20 is a plan view of a multiaxial foundation fabric layer having two different threads sewn into a vertical label stitching area by a row of stitchings performed in a two-stage zig-zag pattern in accordance with the present invention;

Figure 21 is a plan view of a multiaxial foundation fabric layer having Circumflex yarns sewn into the edges of a vertical label closure area and secured in place in a different sewing pattern by fine single thread in accordance with the present invention;

FIG. 22 is a plan view of a multiaxial foundation fabric layer having Circumflex yarns sewn on top of a vertical label closure area and secured in place in a zigzag pattern from the rear by fine single thread in accordance with the present invention; And

FIG. 23 is a plan view of a multiaxial foundation fabric layer having Circumflex yarns sewn into the rear of the vertical label closure area and secured in place at the top and bottom by single thread using twin needles in accordance with the present invention.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

Preferred embodiments of the present invention will be described with reference to FIG. 1. 1 is a plan view of a multiaxial foundation fabric in a flattened state. Once the base fabric 22 is assembled, US Patent Nos. 5,916,421 to Yook and set in common name with the applicant; 5,939,176; And 6,117,274, as shown in plan view in FIG. This consists of the base fabric layer 22 in the form of a two-ply fabric of length L and width W equal to one-half the total length C. The seam 20 between adjacent turns of the woven fabric strip 16 is inclined in one direction at the top of the two strands and in the opposite direction at the bottom strand, as indicated by dashed lines in FIG. 1. The flattened base fabric 22 has two widthwise edges 36.

3 is a schematic cross-sectional view taken along line 6-6 of FIG. According to the present invention, the fabric strip (1) produces a first fabric strand (40) and a second fabric strand (42) bonded to each other at widthwise edges (36) by untied sections of warp (26). Multiple wefts 28 and segments of fabric strip 16 of 16 are removed from adjacent nested portions 38. FIG. 4 is a view similar to FIG. 3, showing a schematic cross-sectional view of one of the two widthwise edges 36 of the flattened base fabric layer 22, with the wefts removed. Untied sections of the warp yarns 26 have suture loops for use in joining the papermaker's fabric to make it infinitely flat from the base fabric layer 22 during installation on the paper machine, as disclosed in Yook's' 176 patent. Form.

2 shows a portion of the surface of the multiaxial foundation fabric layer at a point in one of the overlapped portions 38 near the helical continuous seam 20 between two adjacent spiral turns of the fabric strip 16. Top view. The weft yarn 26 and the warp yarn 28 make a slight angle with respect to the machine direction MD and the cross machine direction CD.

The overlapped portion 38 flattened while removing the neighboring warp 28 is shown in broken lines in FIG. 2. Indeed, the base fabric layer 22 is flattened as described above, and the overlapped portion 38 in the two widthwise edges 36 is displayed in the same manner, and its position becomes apparent when it is flattened. In order to provide the necessary unbound sections of weft 26 at nested portion 38, it is necessary to remove the weft 28 from the area defined by dashed lines 46 and 48, and on the opposite side the nested portion. It is necessary to equally separate from (38). This process is labeling to create a label area of the fabric.

FIG. 5 is a view showing the state in which wefts are removed from the area around the overlapped portion 38, which is a plan view of a part of the surface of the base fabric layer shown in FIG. Untied sections 44 of the wefts 26 extend between dashed lines 46, 48 in the region of the overlapped portion 38. A portion of the weft yarn 50 extending beyond the broken line 46 is removed as described above.

The installation of the untied sections of the warp 26 at the two widthwise edges 36 of the flattened base fabric layer 22 is complicated by two factors. First, because the fabric strip 16 has a smaller width than the base fabric layer 22, the weft 28 does not extend over the entire width of the base fabric layer 22. Secondly, and more importantly, because the fabric strip 16 is spirally wound to create the base fabric layer 22, the wefts do not lie in the cross-machine direction of the base fabric layer 22, resulting in a nested portion ( 38 not parallel. Instead, the weft 28 makes a slight angle, typically less than 10 degrees, relative to the cross-machine direction of the base fabric layer 22. Thus, in order to provide the untied sections of the warp 26 in the overlapped portion 38, the wefts 28 overlap the width W of the base fabric layer 22. It must be removed step by step from.

In other words, since the warp yarns 28 are not parallel to the overlapped portion 38 or the broken lines 46, 48, in order to clarify the space between the broken lines 46, 48 of the weft yarn 28. In a multiaxial fabric, it is necessary to remove only a portion of a given weft 28, as in the case of weft 50 as shown in FIG.

FIG. 5A is a top view of a label area of the multiaxial foundation fabric layer as shown in FIG. 5. Cross-machine direction yarns (horizontal in this figure) along the edges of the label area do not extend across the entire fabric and appear short at some points as they bend into the label area. Since the tails of the cross-machine direction yarns do not extend completely across the fabric, they are likely to migrate into the label / sealing loop area.

6 shows an example of a ball invention in which a suture loop is formed along a nested portion, a schematic cross-sectional view of a flattened base fabric. In this particular method, a loop forming cable 52 is provided for the untied sections of the warp 26 between the first fabric strand 40 and the second fabric strand 42. Sew to connect the first fabric strand 40 and the second fabric strand 42 adjacent the loop forming cable 52 to form, for example, suture loops 56 from the untied sections of the warp 26. 54 is made. Alternatively, the first fabric strand 40 is connected to the second fabric strand 42 adjacent to the loop forming cable 52 by other means used for that purpose to those skilled in the art. The loop forming cable 52 is removed leaving the suture loops 56 formed in the manner described above at the two widthwise edges 36 of the base fabric layer 22.

7 is a view showing a state in which a sealed multi-axial press fabric is installed on a paper machine, a schematic cross-sectional view. FIG. 7 is a laminated fabric with protruding suture loops and comprising a flattened base fabric layer 22 indicated at two nested portions, showing a state in which a sewable fabric 60 is finally formed on the machine. The ends of the sewable fabric 60 on the machine sew one or more layers of staple fiber batting material 80 into the base fabric 60 to perfect the manufacture of the sewn base fabric layer on the machine. By coupling to each other. The staple fiber batting material 80 is made of a polymer resin material, preferably made of polyamide or polyester resin.

FIG. 8 is a plan view of the seaming area of a closed multiaxial press fabric as shown in FIG. As noted above, the major drawback of making seams in multiaxial structures is the occurrence of cross-machine direction tails in the suture area. 8 shows the cross machine direction yarn tail 100 migrating into the suture region. The cross machine direction yarn tail is a function of the cross machine direction yarn angle associated with the panel width, fabric length and panel warp of the multiaxial fabric base. Such cross-machine direction tails are not fixed into the base fabric and are free to move or "migrate" into the seam area. Certain adhesion systems are applied to secure the threads in place, but only within a limited range. When migration occurs, the cross-machine direction yarn ends move into the seaming area and (in some cases seriously) interfere with the seaming.

9 is a schematic enlarged cross-sectional view of a seaming loop area of a flattened base fabric. The cross machine direction yarns or tails 70, 72 are not tied and migrate into the seaming loop area. In particular, the cross-machine direction yarn 70 freely migrates into the suture loop 56 and does not interfere with the suture. In addition, the cross machine direction yarns 72 move around in the seam area, resulting in inconsistent support for the batting material in the seam area. These migrating threads or thread tails create a lot of difficulty when sewing the fabric on a paper machine.

10 is a schematic enlarged cross-sectional view of a suture loop region of a flattened base fabric, showing a continuous cross machine direction yarn woven back to prevent yarn migration in accordance with the present invention. To prevent yarn migration, one embodiment of the present invention weaves a continuous cross machine direction yarn 82 across the width of the fabric along each rim of the label area. Once the fabric is folded and suture loops are formed, this continuous cross machine direction yarn 82 prevents the untied cross machine direction tail yarns from migrating into the suture loop 56. Additional successive cross machine direction yarns 82 may be woven into the label area to impart the desired characteristics to the fabric in the seam area. For example, after allowing a continuous cross-machine direction yarn to provide the ball support in the seam area, thread, thread or string material will be added, among others.

The present invention uses a cross machine direction yarn material attached along the edges of the label area to prevent yarn migration. Cross machine direction yarns include continuous cross machine direction yarns, cross machine direction yarn segments, cross machine direction strips of material, and other suitable materials commonly used in the prior art. The materials are closed by reweaving, sewing / stitching, stapling, gluing, melting, or by techniques known to those skilled in the art. In these embodiments employing a woven material, the cross-machine direction yarn material is again woven using high / low adverbs on either side of the base fabric. In addition, various cross-machine materials are attached in different orders and / or patterns.

FIG. 11 is a plan view of a portion of the surface of the base fabric layer similar to that shown in FIG. 5, with one or more consecutive crossings without leaving tails on the roll and sheet sides of the label area to prevent thread migration in accordance with the present invention. FIG. The machine direction yarn 55 is a figure which shows the state which weaves back into a textile main body. In addition, the Circumflex seal 57 is woven into the body on one or both sides of the label area. This embodiment of the present invention essentially takes advantage of conventional weaving techniques to weave the yarns back into the sealing region of the multiaxial article. In order to prevent migration of cross-machine direction tails while retaining the desired features that are present in woven sutures, the present invention weaves several yarns back into the suture loop area of the multiaxial fabric. First, to accommodate the cross machine direction yarn material, an additional label area is provided that is wider than usual. The width of the label is easily adjusted as understood by those skilled in the art. The new label width is set to the desired width to accommodate the sealing improvement of the present invention. At the minimum width, the label area increases to the width of at least two cross machine direction yarns, which can be applied as many yarn widths as needed. A shed is opened in the label area (the meaning of this is because it is not considered as part of the present invention, because it is performed manually or with full mechanization across the entire width of the fabric). Once the shed is open, the desired weave pattern is selected (does not have the same pattern as the body weave in the sealed multiaxial base). For example, in the phase change where the last cross-machine direction yarn ends or tails appear, two shed fabrics are used to insert two consecutive full width yarns across the border of the label area. Both chambers are inserted and placed simultaneously on either side of the label. Current cross-machine direction tails do not migrate from yarns to these weaves.

12 is a plan view of a multiaxial foundation fabric layer having low melting thread 120 sewn into both sides of a label sealing area in a zigzag pattern to prevent thread migration in accordance with one embodiment of the present invention. "Low melt" is defined as a yarn with a component material having a lower melting point than the polymer used in fabric yarns. The label area is folded during suture forming, stapling and line sewing processes. When the entire fabric is set in a row to stabilize the fabric dimensions, the low melting thread yarns are fused together, thereby fixing the crossmachine direction end threads and tail in place. Alternatively, the sewn zigzag thread can be ultrasonic spot welded against the fabric at various locations.

After the seam is formed, clamped and sewn along the alignment lines, other embodiments of the invention apply. As shown in FIG. 13, the yarn 130 is sewn into a sheath along the suture loop of the multiaxial foundation fabric to prevent thread migration. As shown in FIG. 14, in another embodiment of the present invention, the thread 140 is sewn in a zigzag phantom along the suture loop rim of the multiaxial foundation fabric layer to prevent thread migration. Further, the yarn 130 of FIG. 13 and the yarn 140 of FIG. 14 become low melting point yarns similar to the yarn 120 described above with reference to FIG. 12.

Another embodiment of the present invention inserts a low melting point nonwoven strip 150 into the fold / label area of the multiaxial foundation fabric layer before heat setting the suture loop to prevent thread migration as shown in FIG. 15. When the loops are heat set, the strip forms an adhesive when it is cooled to hold the cross machine direction yarns in place, thereby preventing thread migration. Alternatively, before the fabric is folded to form a seam, a low melting nonwoven strip 150 is attached over one side of the label area so that when the fabric is folded to form a seam loop, the nonwoven strip is located inside the seam area. (Ie by ironing or by glue).

The seal material is any material suitable for reducing seam wear, seam protruding or noise in the uhle box and / or reducing seam plane differences to improve sealing time and the like. The seal diameter is smaller than the cross machine direction yarn body diameter, thereby reducing the plane difference imposed on the seam. The yarns may be made of a heat-fusible cover or heat-fusible fiber pre-attachment layer with much smaller diameters, braided yarns of heat-fusible material, or simply made of standard single thread material. These rewoven yarns can be fused into place.

As described herein, the added yarns are inserted, woven and / or sewn as necessary, either manually or by machine to prevent thread migration. In addition, these threads may be added and / or sewn in a variety of patterns, including but not limited to zigzag stitch patterns or cover stitch patterns as described herein.

If desired, additional cross machine yarns may be inserted in succession on each side of the label to produce a fabric having the desired fabric properties and width. For example, it is desirable to insert other seals as Circumflex seals as described above to reduce seam wear, marking and noise. These Circumflex yarns are optional and can be inserted in the same way to improve the sealed product.

As noted above, the improved seam is made to ensure adequate uniform support for the fiber ball material in the sealing area. This is accomplished through the addition of one or more additional yarns in the label area. Essentially, additional threads serve as replacements for the different calipers, and the properties of the seam area are at least partially caused when the original cross machine direction yarn body is removed to produce a label. These yarns are a suitable combination of Circumflex and other types of yarns. In addition, various sewing and other techniques are used to secure the threads. 16 to 23 illustrate a number of exemplary suitable combinations in accordance with the present invention. Each figure shows a top view of a multiaxial foundation fabric layer with vertical label closure regions. In FIG. 16, the Circumflex yarn 160 is sewn into the label stitching area and sewn in a zigzag pattern by the fine single thread 170 to be fixed in place. The Circumflex thread is placed at a predetermined position between the edges of the label area. In FIG. 17, the Circumflex yarn 160 is sewn into the rim of the label stitching area. FIG. 18 shows a thin short or fine cover / core thread 180 stitched into a label closure area. This thread is placed at a predetermined position between the edges of the label area. 19 shows two different threads that are sewn into the rim of the label stitching area by two rows of stitching 190. Different yarns have different coarseness, size and material. 20 shows two different threads sewn into the label stitching area by one row of stitching performed with the two-stage zig-zag pattern 200. 21 shows additional yarns that are sewn into the rim of the label stitching area and secured in place with another stitching pattern 210 by fine shorty yarns. Appropriate form of stitching is used. FIG. 22 shows a Circumflex yarn sewn on top of the label stitching area and secured in place in a zigzag pattern 220 using twin needles (not shown) at the back by fine single threaded yarns. Likewise, FIG. 23 shows a Circumflex thread that is sewn into the rear of the label closure area and secured in place at the top and bottom by single thread using twin needles.

The present invention not only prevents cross-machine direction migration that impedes the stitching of the fabric, but the width of the label area and the weaving pattern of the inserted yarns are inherently present in the woven suture product although previously not possible in multiaxial suture products in the suture area May be selected to impose various characteristics. Therefore, the present invention provides the ability to combine the inherent advantages of multiaxial base fabrics with the inherent advantages of woven suture fabrics.

For example, heat fusion single yarns are not desirable as cross-machine direction yarns for fabric bodies (especially before bonding), and cover / core heat fusion capable yarn technology is expensive. However, heat fusion capable or adhesive activating seals can provide advantages and cost effectiveness when introduced into the sealing area prior to heat setting the loop. The melting point of these materials can be chosen so that these yarns are not activated during the loop heat setting process, but are activated during the final curing process, and all cross machine direction yarn ends are joined and joined before cutting the seam and conveying the fabric to the consumer. Prepare for fixation.

Woven fabrics to provide a machine sewable fabric form a single layer or multiple layers and are woven from single, multi-ply or multi-threaded synthetic polymer resins such as polyester or polyamide. The yarns forming the suture loop 56 and forming the weft yarn are preferably single thread yarns.

Fabrics according to the present invention include yarns made of polyester, polyamide, polybutylene terephthalate (PBT), or other polymers as known to those skilled in the art. Bicomponent or sheath / core seals may be employed. Combinations of polymers for the yarns are distinguished by those skilled in the art. Cross-machine direction yarns and machine direction yarns have a circular cross-sectional shape with one or more different diameters. Further, in addition to the circular cross-sectional shape, one or more cross machine direction yarns, machine direction yarns, or rewoven / sewn yarns may have other cross-sectional shapes, such as rectangular cross-sectional shapes or circular cross-sectional shapes.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be able to variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. It will be appreciated.

Claims (41)

A method of sewing an on-machine-seamable multiaxial papermaker's fabric that is sewn on a machine in the form of an endless loop that is flattened into two layers along a first nested portion and a second nested portion. Removing cross-machine direction yarns from the first and second nested portions to form level regions, wherein the machine direction yarns are not tied in the label region; Forming suture loops from machine direction yarns not tied to the first nested portion and the second nested portion; Attaching a cross machine direction yarn material along the edges of the label area at each nested portion, whereby the threads are bound along the cross machine direction yarn edges of the label area; And Sewing the fabric by overlapping the suture loops from the first nested portion and the second nested portion and inserting a pintle therebetween. 2. The method of claim 1, further comprising weaving at least one additional cross machine direction yarn into the label area to impart desired features to the seam of the fabric. 3. The method of claim 2, wherein said additional cross machine direction yarn is a Circumflex yarn. The method of claim 1 wherein the cross-machine direction yarn material to be attached is yarns having a thermofusible sheath / core or a preadhesive layer of heat fusionable fibers or braided threads of heat fusionable material. How to sew. The method of claim 1 wherein the cross machine direction yarn material to be attached is a flat strip material. 2. The method of claim 1 wherein the adhering cross machine direction yarn material is an attached cross machine direction yarn, wherein the diameter of the adhering cross machine direction yarn is smaller than the diameter of the cross machine direction yarn in the fabric, thereby reducing the plane difference of the seam. The sewing method characterized by. 2. The yarn of claim 1 wherein the threads in the fabric are at an angle to the cross machine direction yarns and the machine direction yarns, such that at least some of the cross machine direction yarns removed along the edges of the label area are of the fabric. Sewing method characterized in that it does not extend across the full width. The woven fabric strip of claim 1, wherein the fabric is formed of a woven fabric strip having a width less than the width of the fabric, the woven fabric strip having two lateral edges, wherein the lateral edges are formed of the woven fabric strip. And when adjacent spiral edges of the woven fabric strip are overlapped to form a spiral wound seam. 2. The method of claim 1, further comprising stitching at least one layer of staple fiber batting material into the fabric. 10. The method as claimed in claim 9, wherein the fabric is a thin plate-shaped multiaxial press fabric sewable on a machine for the press section of the paper machine. The method of claim 1 wherein the adhering cross-machine direction yarn material is yarns and at least some of the yarns are polyamide, polyester, polybutylene terephthalate (PBT), or dual component sheath / core yarns. Sewing method. The method of claim 1 wherein the cross machine direction yarn material to be attached has a circular cross-sectional shape, a rectangular cross-sectional shape or a non-circular cross-sectional shape. 2. The method of claim 1, wherein said attaching comprises weaving successive cross machine direction yarns along the edges of said label area. 14. The method of claim 13 wherein the label area is made wide to accommodate continuous cross machine direction yarns woven again in the suture loops. As a papermaker's fabric, (Iii) a multiaxial fabric base in the form of an endless loop that is flattened in two layers along a first nested portion and a second nested portion, the multiaxial fabric base being the first nested portion and the second nested portion; Along the nested portion there are suture loops formed from machine direction yarns not tied to the label area, the label area being formed by removing the yarns from the cross machine direction yarns, thereby forming a machine direction yarn not tied to the label area. A multiaxial fabric base, where threads are left; And (Ii) cross-machine direction yarn materials attached to the fabric base along the edges of the label area at each nested portion, thereby binding the threads along the cross machine direction yarn edges of the label areas; Papermaker weaving. 16. The papermaker's fabric according to claim 15, wherein the fabric is sewn by overlapping suture loops from the first and second nested portions and inserting a pintle therebetween. 16. The papermaker's fabric according to claim 15, further comprising at least one additional cross-machine direction yarn woven back into the label area to impart desired features to the seam of the fabric. 18. The papermaker's fabric according to claim 17, wherein said additional cross machine direction yarn is Circumflex yarn. 16. The papermaker according to claim 15 wherein the attached cross-machine direction yarn material is yarns having a thermofusible sheath, a prebonded layer of heat fusionable fiber, or a braided thread of heat fusionable material. textile. 16. The papermaker's fabric according to claim 15, wherein the attached cross-machine direction yarn material is a flat strip material. The method of claim 15 wherein the attached cross machine direction yarn material is attached cross machine direction yarns, the diameter of the attached cross machine direction yarns being smaller than the diameter of the cross machine direction yarns at the fabric base, thereby reducing the plane difference of the seam. Papermaker's fabric characterized in that. 16. The yarn of claim 15 wherein the yarns in the fabric base are at an angle to the cross machine direction yarns and machine direction yarns, such that at least some of the threads removed from the cross machine direction yarns along the edges of the label area are Papermaker's fabric, characterized in that it does not extend across the entire width of the fabric. The fabric base of claim 15, wherein the fabric base is formed of a woven fabric strip having a width less than the width of the fabric, the woven fabric strip in the form of a multilayer fabric having two lateral edges, wherein the lateral edges are Wherein the woven fabric strip is formed when it is continuously spiral wound to form a fabric base, wherein adjacent lateral edges of the woven fabric strip overlap to form a spiral wound seam. 16. The papermaker's fabric according to claim 15, wherein the fabric is a thin plate-shaped multiaxial press fabric sewn on a machine with respect to the press section of the paper machine. 16. The papermaker's fabric according to claim 15, comprising at least one layer of staple fiber batting material stitched into the fabric. 16. The papermaker's fabric according to claim 15, wherein the attached cross-machine direction yarn material is yarns and at least some of the yarns are polyamide, polyester, polybutylene terephthalate (PBT) yarns. 16. The papermaker's fabric according to claim 15, wherein the attached cross-machine direction yarn material is yarns and at least some of the yarns have a circular cross-sectional shape, rectangular cross-sectional shape or non-circular cross-sectional shape. 16. The papermaker's fabric according to claim 15, wherein the cross machine direction yarn materials attached to the fabric base are continuous cross machine direction yarns woven back into the fabric base. 29. The papermaker's fabric according to claim 28, wherein the label area is made wide to accommodate continuous cross machine direction yarns woven again in the suture loops. 2. The papermaker's fabric according to claim 1, wherein the cross machine direction yarn materials are attached along the edges of the label area using a zigzag stitch pattern. 2. The papermaker's fabric according to claim 1, wherein the cross machine direction yarn materials are attached along the edges of the label area using a cover stitch pattern. 16. The papermaker's fabric according to claim 15, wherein the cross machine direction yarn materials are attached along the edges of the label area using a zigzag stitch pattern. 16. The papermaker's fabric according to claim 15, wherein the cross machine direction yarn materials are attached along the edges of the label area using a cover stitch pattern. A method of sewing a multiaxial papermaker's fabric sewable on a machine having the form of an endless loop that is flattened into two layers along a first nested portion and a second nested portion, Removing cross-machine direction yarns from the first and second nested portions to form level regions, wherein the machine direction yarns are not tied in the label region; Forming suture loops from machine direction yarns not tied to the first nested portion and the second nested portion; Attaching the edges of the label area at the cross machine direction yarns using a stitching pattern at each nested portion, whereby the threads are tied along the cross machine direction yarn edges of the label area; And Sewing the fabric by overlapping the suture loops from the first nested portion and the second nested portion and inserting a pintle therebetween. 35. The papermaker's fabric according to claim 34, wherein said stitching pattern is a zigzag stitching pattern. 35. The papermaker's fabric according to claim 34, wherein the stitch pattern is a cover stitch pattern. 35. The papermaker's fabric according to claim 34, wherein the cross machine direction yarn materials are attached along the edges of the label area using a sewing pattern. As a papermaker's fabric, A multiaxial fabric base in the form of an endless loop flattened into two layers along the first and second nested portions, The multiaxial fabric base has suture loops formed from machine direction yarns not tied to the label area along the first and second nested portions, the label area having yarns in the cross machine direction yarns. Formed by removal, which leaves threads in machine direction yarns not tied to the label area, The cross machine direction yarn edges of the label areas in the cross machine direction yarns are attached at each nested portion using a stitching pattern, whereby the yarns are bound along the cross machine direction yarn edges of the label areas. textile. 39. The papermaker's fabric according to claim 38, wherein said stitching pattern is a zigzag stitching pattern. 39. The papermaker's fabric according to claim 38, wherein said stitching pattern is a cover stitching pattern. 39. The papermaker's fabric according to claim 38, wherein the cross machine direction yarn materials are attached along the edges of the label area using a sewing pattern.

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