Spirally wound press felt with orthagonal SEAM loops and method

Abstract

A seamed industrial fabric includes a base fabric formed from a material strip having a width that is less than a CD base fabric width. This strip includes longitudinal edges that are bonded to adjacent longitudinal edges to define an overall base fabric width. The strip includes generally MD oriented yarns held together by a fabric material component. Ends of the strip are joined along a CD join path to form a fabric loop with the generally MD oriented yarns being arranged in a true MD. The loop is collapsed so the MD oriented yarns form superimposed layers joined by bent-back regions of the MD oriented yarns that form seam loops that extend in the true MD at each fabric end. A pintle extends through intermeshed seam loops from the opposing ends to form a seam. The CD join path may be located on an internal surface of the base fabric.

Description

SPIRALLY WOUND PRESS FELT WITH ORTHAGONAL SEAM LOOPS AND METHODCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority from U.S. Provisional Application No. 63 / 586,138 filed September 28, 2023, which is incorporated herein by reference as if fully set forth.FIELD OF THE INVENTION

[0002] The invention generally concerns seamed industrial fabrics, and more particularly press felts for use in the manufacture of paper and similar products in a papermaking or like machine. It is particularly concerned with spiral bonded felts.BACKGROUND

[0003] In the manufacture of paper products, a stock slurry consisting of about 1% papermaking fibers and other solids dispersed in about 99% water is delivered at high speed and precision from a headbox slice onto a rapidly moving forming fabric, or between two forming fabrics, in the forming section of a papermaking machine. The stock is subjected to agitation and is dewatered by various means through the forming fabrics, leaving behind a loosely cohesive and wet web of fibers. This web is then transferred to the press section where a further portion of water is removed by mechanical means as the web, supported by one or more press felts, passes through at least one, and usually a series, of press nips where water is essentially squeezed from the nascent sheet and into the press felt. The water is accepted by the press felt and, ideally, does not return to the web. The resulting sheet is then passed to the dryer section which includes a series of rotatable dryer drums, or cans, that are heated by steam. The sheet is directed around and held in contact with the periphery of these drums by one or more dryer fabrics so that the majority of the remaining water is removed by evaporation.

[0004] Press felts play a critical role in the manufacture of paper products. The known press felts are produced in a wide variety of styles designed to meet the requirements of the papermaking machines on which they are installed, and the paper grades being manufactured. They are generally assembled using a woven or nonwoven base fabric structure into which is needled one and usually multiple layers of a fibrous nonwoven batt. The batt provides a smooth surface upon which the paper product is conveyed, acts as a reservoir to trap water expressed at the press nip, and provides a measure of resiliency to the press felt as it passes through the nip. The base fabrics are typically woven from monofilament, cabled monofilament, multifilament or similar multicomponent yarns; they may also be arranged as nonwoven planar arrays. Thecomponent yarns are usually comprised of an extruded polymeric resin, typically a polyamide.

[0005] The base fabrics may be of single layer or multilayer construction, or they may be formed from two or more layers which are laminated together.

[0006] “Multiaxial fabrics” are known for the production of press felts. Multiaxial press felts are described in US 5,360,656; US 5,268,076; US 5,785,818 and others. The base fabrics of these press felts are comprised of a plurality of spirally wound and edgewise joined turns of a material strip including at least machine direction (MD) oriented yarns. The material strip is usually a flat woven fabric which is narrower than the width of the intended base fabric of which it is a component. It has also been proposed to use nonwoven arrays of MD yarns as the material strip component. Regardless of whether the component is woven or nonwoven, during assembly each turn of the material strip is directed about two opposing rollers such that its component MD yarns are canted at a small angle that is from about 10to about 8° to the intended MD of the finished fabric; see prior art Figure 1 . Each successive turn of the material strip is edgewise bonded to the adjacent turn of the material strip so as to build up a continuous tube-like base fabric of desired width and length. When removed from the assembly rollers and laid flat, the tube has continuous top and bottom surfaces joined at cross-machine direction (CD) oriented fold regions at each of the two opposing ends; see prior art Figure 2. The completed multiaxial base fabrics are typically one of a two, three or four layer construction comprising the top and bottom surfaces of the spirally wound continuous tube, and optionally at least one additional flat fabric layer, located either interior to the flattened tube, or on top of one or both exterior surfaces. The assembled base fabrics may later be provided with a seam to facilitate their installation on the machine for which they are intended.

[0007] Figure 3 shows the two opposing edge regions of a spirally wound prior art double layer woven structure with a portion of the CD oriented yarns removed at the opposing fold regions. This exposes the MD oriented yarns of the structure so that the yarn loops may be used to form a seam in the fabric as illustrated in Figure 4. This Figure shows a double layer fabric that has been seamed by intermeshing the yarn loops formed by the MD yarns at the fold region and inserting a pintle across the length of the channel thus provided.

[0008] For the seamed press felt, and particularly in the case of multiaxial fabricbased press felts, there are several seam related issues. These include differences in the physical characteristics of the fabric in the seam area resulting in different resiliency and different air permeability, which can result in sheet break due to lower strength of the paper sheet at the seam mark, as well as marking of the finished paper. The seam region is thus usually recognized as the most critical area of the finished fabric.

[0009] Further issues present in these seam constructions include loop stretching and poor seam loop stability, as well as the MD seam loops being canted in the multiaxial constructions resulting in non-uniformities and more difficult seaming.

[0010] It would be desirable to provide a base fabric construction which improves upon the known issues particularly for multiaxial press felt constructions.SUMMARY

[0011] In one aspect, a seamed industrial fabric is provided that includes a base fabric formed from at least one material strip having a width that is less than a CD width of the base fabric. The at least one material strip includes longitudinal edges that are bonded to adjacent ones of the longitudinal edges of the at least one material strip in order to define an overall base fabric width. The at least one material strip includes generally MD oriented yarns that are held together relative to one another by an additional fabric material component, and the at least one material strip has cut ends that are joined along a CD join path in order to form a fabric loop with the generally MD oriented yarns being arranged in a true MD. The fabric loop is collapsed such that the MD oriented yarns are arranged in the base fabric as two superimposed layers joined by bent-back regions of the MD oriented yarns at CD oriented fold regions at each of the two opposing ends thereof. The additional fabric material component is removed from the MD oriented yarns in the CD oriented fold regions to form seam regions having seam loops formed of the MD oriented yarns extending in the true MD. A pintle extends through a channel defined by intermeshing the seam loops from the two opposing ends to form a seam. Additionally, the CD join path is preferably located on an internal surface of the base fabric, preferably spaced apart from the seam regions. In applications such as press felts for papermaking, locating this CD join path on the internal surface reduces the likelihood of sheet marking of a paper or cardboard sheet supported on a paper support surface of the fabric. This can also have advantages in other applications.

[0012] With this arrangement, several issues with the known multiaxial constructions are addressed. First, density differences in the seam region are reduced in comparison to the prior multiaxial constructions. Additionally, the seam loop length is more uniform, and the sawtooth gap with pickets (cut CD yarn ends) is reduced or eliminated. Further, the seam loops are aligned straight and do not lean, allowing for easier seaming. Overall, this improves the properties of the base fabric in the seam region.

[0013] In one embodiment, batt material needled to at least one of an inner surface or an outer surface of the base fabric. More preferably, batt material is needled to both the inner and outer surfaces. It is also possible to insert batt material, non-woven material, and / or an additional woven material layer within the fabric loop prior to the fabric loop beingcollapsed to adjust properties, such as air permeability, caliper, etc. of the seamed industrial fabric.

[0014] In one embodiment, the fabric is a press felt and the outer surface is a paper support surface.

[0015] In one arrangement, the at least one material strip is a spirally wound material strip, and the generally MD oriented yarns are initially arranged canted at an angle to the true MD. Here, the cut ends are realigned prior to being joined along the CD join path in order to arrange the generally MD oriented yarns of the spirally wound material strip in the true MD.

[0016] In one embodiment, the at least one material strip comprises a woven material, and the additional fabric material component comprises generally CD oriented yarns interwoven with the generally MD oriented yarns. Alternatively, the generally MD oriented yarns can be held together by a bonded or adhered scrim or non-woven material(s).

[0017] In one embodiment, the seam regions each include at least one stuffer yarn located adjacent to the seam loops formed by the MD oriented yarns at the CD fold regions. The one or more stuffer yarns are used depending on the particular application to adjust permeability and / or caliper in the seam regions.

[0018] In one embodiment, the generally MD oriented yarns are stacked generally MD oriented yarns. Here, the MD oriented yarns on the inner and outer surfaces of the are generally arranged as stacked pairs in the base fabric.

[0019] In another aspect, a method of producing a seamed industrial fabric is provided. The method includes:

[0020] A) forming a base fabric from at least one material strip including generally MD oriented yarns that are held together relative to one another by an additional fabric material component, the at least one material strip having a width that is less than a CD width of the base fabric, by bonding adjacent longitudinal edges of the at least one material strip in order to define an overall base fabric width;

[0021] B) joining cut ends of the at least one material strip along a CD join path in order to form a fabric loop with the generally MD oriented yarns being arranged in a true MD;

[0022] C) collapsing the fabric loop such that the MD oriented yarns are arranged in the base fabric as two superimposed layers joined by bent-back regions of the MD oriented yarns at CD oriented fold regions at each of the two opposing ends thereof;

[0023] D) removing the additional fabric material component from the MD oriented yarns in the CD oriented fold regions to form seam regions having seam loops formed of the MD oriented yarns extending in the true MD; and

[0024] E) intermeshing the seam loops from the two opposing ends and inserting a pintle through the intermeshed seam loops to form a seam.

[0025] In one embodiment, step A of the method further includes spirally winding the at least one material strip to form a spirally wound material strip, and then cutting across the spirally wound material strip, realigning the cut ends such that the generally MD oriented yarns extend in the true MD, prior to joining the cut ends in order to form the fabric loop.

[0026] In one embodiment, the method further includes needling batt material to at least one of an inner surface or an outer surface of the base fabric.

[0027] In a preferred embodiment, the method is used to form a seamed industrial fabric which is a press felt, and the outer surface is a paper support surface. Preferably, the CD join path is located on an internal surface of the base fabric. This reduces the likelihood of sheet marking of a paper or cardboard sheet supported on a paper support surface of the fabric.

[0028] In one embodiment, the at least one material strip comprises a woven material, and the additional fabric material component comprises generally CD oriented yarns interwoven with the generally MD oriented yarns.

[0029] In one embodiment, the generally CD oriented yarns adjacent to the seam loops extend in a true CD and therefore extend uncut across the width of the at least one material strip.

[0030] In another embodiment, the method further includes inserting at least one stuffer yarn adjacent to the seam loops formed by the MD oriented yarns at the CD fold regions.

[0031] In another embodiment, the method includes providing the at least one material strip with the generally MD oriented yarns with a stacked arrangement, and removing a portion of inner ones of the stacked MD oriented yarns in the seam regions.

[0032] The above-noted features may be used separately or in combinations with other ones of the noted features.BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The foregoing Summary and the following detailed description and claims will be best understood when read in conjunction with the drawings which show the presently preferred embodiments of the invention. In the drawings:

[0034] Figure 1 is an illustration showing a known spiral winding process in which a strip of relatively narrow fabric 10 is spirally wound from a feed source 20 around two opposed rolls 22, 24 to produce a desired width and length of base fabric. Each successive turn of strip 10 is bonded to that to which it is laid adjacent in the process to provide the base fabric.

[0035] Figure 2 is a view of a known continuous tube-like base fabric 30 including opposing fold regions 32 and 34; fabric 30 may be made from successive turns of the narrow fabric 10 in the manner illustrated in Figure 1 , or it may be produced by a modified endless weaving process, a flat weaving process where opposing ends of the flat woven cloth are joined to provide a continuous tube, or it may be a nonwoven cohesive assembly of yarns oriented in the length direction around the tube.

[0036] Figure 3 is an enlargement of the two fold regions 32, 34 of the base fabric 30 presented in Figure 2 which form the seam region in the prior art fabrics shown in Figures 1 and 2.

[0037] Figure 4 is a schematic illustration of the seam region in a prior art base fabric 30 such as presented in Figures 1 to 3 including a pintle 18 to join the seam loops of the fold regions 32, 34. This is shown prior to needling of one or more batt layers to the base fabric 30.

[0038] Figure 5 is a top view of a seam area 40 of a multiaxial base fabric 30 of the prior art, prior to the tube being folded and then collapsed to form seam loops.

[0039] Figure 6 is a side view of a double layer seam gap of a multiaxial base of the prior art.

[0040] Figure 7 is a side view of the seam area of a folded double layer multiaxial base fabric of the prior art with the two ends joined and a pintle inserted in the channel formed by the seam loops.

[0041] Figure 8 is a view similar to Figure 7 following the needling of batt to both surfaces of the press felt according to the prior art.

[0042] Figure 9 is a view of Figure 8 depicting cumulative filament stretch and filament slippage inside the batt and weft at the seam loops in the press felt according to the prior art.

[0043] Figure 10 is afront view of the seam loops as seen from the running direction in application of a multiaxial base fabric of the prior art.

[0044] Figure 11 is a top view similar to Figures of a seam area 40 of a multiaxial base fabric 30 of the prior art in a region where successive turns of the strip 10 are bonded and stitched together, prior to the tube being collapsed to form seam loops according to the prior art.

[0045] Figure 12 is a front view similar to Figure of the seam loops as seen from the running direction in the area where successive turns of the strip 10 are bonded and stitched together in a base fabric of the prior art.

[0046] Figure13 is a top view of the seam region at one end of the base fabric shown in Figure 11 after the tube has been collapsed in a base fabric according to the prior art.

[0047] Figures 14A-14F are a series of views showing the steps in the construction of a base fabric according to the present disclosure.

[0048] Figure 15 is a top view similar to Figure 1 1 showing the base fabric according to the present disclosure prior to the fabric loop or tube formed from at least one material strip that has the longitudinal edges bonded or connected together to an adjacent portion of the at least one material strip being collapsed.

[0049] Figure 16 is a side view of a double layer of the generally MD oriented yarns in the material strip that are generally stacked in the seam region.

[0050] Figure 17 is a side view similar to Figure 16 in which a portion of inner ones of the stacked MD oriented yarns in the seam region are removed.

[0051] Figure 18 is a side view of the seam area of a folded double layer base fabric according to the disclosure with the two ends joined and a pintle inserted in the channel formed by the seam loops.

[0052] Figure 19 is a top view of the seam region of the folded double layer base fabric according to the disclosure shown n Figure 18.

[0053] Figure 20 is a front view of the seam loops as seen from the running direction in application of the folded double layer base fabric of Figures 18 and 19.DETAILED DESCRIPTION

[0054] Certain terminology is used in the following description for convenience only and is not limiting. The words "top," "bottom," "upper" and "lower" designate directions in the drawings to which reference is made. A reference to a list of items that are cited as "at least one of a, b, or c" (where a, b, and c represent the items being listed) means any single one of the items a, b, or c, or combinations thereof. “A” or “an” refer to one or more of the item noted. “MD” refers to a machine direction in the papermaking machine from the headbox to the dryer section and is the longitudinal direction of the press felt. “CD” refers to the cross-machine direction, or a direction perpendicular to the machine direction in the plane of the fabric. The term “PS” refers to the paper side surface of the fabric, which is the surface upon which the paper product is carried through the papermaking machine. “MS” refers to the machine side of the fabric and is the surface opposite to the PS. Unless otherwise specified, the term “yarn” or “yarns” refers to a continuous length of either single or cabled polymeric monofilament such as would be used in the manufacture of the base fabrics, while the term “fiber” or “fibers” refers to relatively small diameter polymeric materials such as those commonly used in batt or scrim materials which fibers have a very small dtex (mass in grams per 10,000 meters of fiber). The terms “left”, “right”, “up”, “down” are used in relation to the drawings and have the meanings usually assigned. The terms “about” and “generally”, unless otherwise noted, means + / - 10% of the noted value.Reference to a “true” direction, such as a “true MD direction” means within less than 1 ° of the actual direction referenced. Additional definitions for terms used herein are as follows:

[0055] Additional Definitions:

[0056] “Press felt base fabric” or “base fabric”: a woven or nonwoven assembly of yarns provided as an endless structure or continuous loop including two superimposed layers joined (when laid flat) at two opposing fold regions, including continuous MD yarns passing around the folds. The assemblies can take the form of: a) an endless woven structure, b) a modified endless woven structure, c) a flat woven fabric folded at two locations to provide a double layer assembly, d) a fabric formed according to a multiaxial assembly process, or e) a multiaxial or non-multiaxial nonwoven structure assembled to provide any of the previous assemblies. The present invention is applicable to all of the above, but it is particularly suitable for use in both woven and nonwoven multiaxial base fabric constructions. All of the base fabrics are post processed to provide seam loops formed by bent-back regions of the MD oriented component yarns allowing the fabric to be joined and thus rendered endless. These base fabrics provide the finished press felt with the physical properties (strength, void volume, resiliency) necessary for it to survive the rigors of the machine environment in which it will be used, while providing a rugged carrier for the batt fibers.

[0057] Referring to Figures 1-4, one construction of a press felt base fabric 30 in accordance with the prior art is shown, in this case a multiaxial construction. Figure 1 shows a strip of material, which can be woven or non-woven and including generally MD oriented yarns 12 and generally CD oriented yarns 16, being unwound from a source 20 and wrapped around two rolls 22, 24. The longitudinal edges of the strip are joined together to form a fabric tube. Figure 2 shows the fabric tube collapsed to form the press felt base fabric 30 having two fold regions 32, 34, that define the fabric ends 36, 38. As shown in Figure 3, continuous ones of the generally MD yarns 12 form loops 14 at each of the fold regions 32, 34 at the fabric ends 36, 38 that can be intermeshed in a known manner to form a pintle channel 19 in which a pintle 18 is inserted, as shown in Figure 4, to form an endless base fabric 30. In the prior art these generally MD oriented yarns are canted from about 10to about 8°, but are not in the true MD due to the spirally wound construction.

[0058] In the case of a multiaxial press felt base fabric 30, as well as other double layer base fabrics, the double layer formed by collapsing the fabric tube is connected together in a needling process in which one or more layers of a nonwoven fibrous batt material are attached to the base fabric 30 in a needling process to form the press felt.

[0059] Referring to Figures 5-13, a further embodiment of a multi-axial press felt base fabric 30 is shown. Here, the base fabric 30 is again produced from a fabric strip 10; however, the fabric strip 10 includes two systems of MD yarns 12a, 12b that are providedin a stacked arrangement, as shown in Figure 6. These two systems of MD yarns 12a, 12b are connected together by a system of CD oriented yarns 16 and, as shown in Figure 5, are arranged at a canted angle to a true MD based on the multi-axial construction of the spirally wound base fabric 30. As shown in Figures 5 and 6, the CD oriented yarns 16 as well as a portion of the lower system of MD yarns 12b are removed in a seam area 40. As shown in Figure 5, this results in uneven end portions of the CD oriented yarn 16 at the edges of the seam area 40. Figure 11 is a view similar to Figure 5 and shows the longitudinal edges of the strip 16 are joined together by stitching 17 as well as bonding.

[0060] As shown in Figure 7, and in a similar manner to Figures 2-4 as discussed above, the fabric tube is collapsed to form the press felt base fabric 30 with the two seam or fold regions 32, 34 that define the fabric ends. These fold regions 32, 34 have seam loops 14 formed by bent-back regions of continuous ones of the MD yarns 12a of the upper (now outer) system of MD yarns 12a. These seam loops 14 are intermeshed in a known manner to form a pintle channel 19 into which a pintle 18 is inserted in order to form an endless base fabric 30.

[0061] As shown in Figure 8, one or more layers of a non-woven fibrous batt material 50 are attached to the base fabric 30 via a needling process in order to form the prior art press felt.

[0062] As shown in Figure 9, due to the tensile load applied to the press fabric in use, seam loop elongation can occur resulting in seam marking on the paper sheet being carried by the press felt as well as premature failure of the press felt.

[0063] Figure 10 is an end view of the prior art base fabric 30 which shows the seam loops also at a canted angle relative to true horizontal plane defined by the press felt due to the multiaxial spirally wound construction of the base fabric 30 with the yarns canted from 1 ° to 8° from the true MD and CD. Figure 12 is a similar view taken in the region where the longitudinal edges of the strip 10 are joined together via stitching 17 and bonding. Figure 13 is a top view of the seam region 32 at one end of the base fabric 30 shown in Figures 11 and 12 after the tube has been collapsed to form the base fabric 30 that illustrates how the seam loops 14 become canted. This makes seaming / pintle 18 installation for the known multiaxial press felt more difficult when installing the press felt onto a paper making machine.

[0064] Referring now to Figures 14A-14F and 15 - 20, a seamed industrial fabric 100 (fabric 100) in accordance with the present disclosure as well as its method of manufacture is described in detail. The fabric 100 is includes a base fabric 130 that is formed of at least one material strip 1 10 that includes generally MD oriented yarns 112 that are held together relative to one another an additional fabric component, which could be generally CD oriented yarns 116 or a nonwoven material, a scrim, or mesh. In the illustratedembodiment, the fabric strip 110 is a woven fabric strip which includes the generally MD oriented yarns 112 interwoven with the generally CD oriented yarns 1 16 The at least one material strip 110 has a width that is less than a CD width of the fabric 100 and adjacent longitudinal edges of the at least one material strip 110 are connected together, for example by bonding, fusing and / or stitching 117, in order to define an overall base fabric width.

[0065] In one embodiment, as shown in Figure 14A, the method includes spirally winding the at least one material strip 110 to form a spirally wound material strip 110 in which the MD yarns are canted from 1 ° to 8° from the true MD, and then cutting across the spirally wound material strip 1 10, realigning the cut ends 11 1A, 1 11 B such that the generally MD oriented yarns 1 12 extend in the true MD as shown in Figures 14B, 15, and 19, and then joining the ends 11 1A, 11 1 B together, for example by fusing, bonding, and / or stitching, along a CD join path 126, as shown in Figure 14C to form a fabric loop. Alternatively, more than one of the material strips 110 can be assembled directly into the configuration shown in Figure 14B, with the longitudinal edges being joined to the longitudinal edges of adjacent ones of the material strips 110 in order to define an overall base fabric width without spiral winding. Here, the generally MD oriented yarns 1 12 would be oriented in the true MD as shown in Figures 14B, 15, and 19, and the endsl 1 1A, 111 B are joined together, by fusing, bonding, and / or stitching in order to form the CD join path 126 as noted above and shown in Figure 14C to form the fabric loop.

[0066] As shown in Figures 14 D and 14E, the fabric loop is collapsed such that the MD oriented yarns 112 are arranged in the base fabric 130 as two superimposed layers (shown in Figures 18 and 19) joined by bent-back regions of the MD oriented yarns 112 at CD oriented fold regions 132, 134 at each of the two opposing ends 136, 138 of the base fabric 130. The additional fabric material component, such as the generally CD oriented yarns 1 16 (now oriented in the true CD) are removed from the MD oriented yarns 1 12 in the CD oriented fold regions 132, 134 to form seam regions having seam loops 114 formed by bent-back regions of continuous ones of the MD oriented yarns 112 which extend in the true MD. In the illustrated embodiment, the fabric strip 110 has stacked generally MD oriented yarns 112A, 112B, and as shown in Figures 16 and 17, portions of the generally MD oriented yarns 112B (now oriented in the true MD) that are on the inside of the fabric loop are also removed such that the seam loops 1 14 are formed by only the generally MD oriented yarns 112A (now oriented in the true MD) that are on the outside of the fabric loop.

[0067] As shown in Figures 14F, 18, and 19, these seam loops 114 are intermeshed in a known manner to form a pintle channel 1 19 into which a pintle 1 18 is inserted in order to form the endless base fabric 130. In one embodiment, as shown in Figure 14F, the CD join path 126 can be located on an internal surface of the base fabric 130. This has advantages in press felt applications for the fabric 100. It is also possible forthe CD join path 126 to be located on the external surface. The pintle 118 can be a single or multi-filament yarn. Additionally, one or more stuffer yarns 115 may be arranged in the areas between the opposing fabric ends 136, 138 outside of the pintle channel 119 to improve the consistency of the base fabric 130 properties in the seam region.

[0068] In one application, the fabric 100 is a press felt and the outer surface is a paper support surface. Here, as schematically represented in Figure 20, non-woven fibrous batt material 150 is needled to at least one of an inner surface or an outer surface of the base fabric 130, and specifically, at least to the outer surface which forms the paper support surface.

[0069] As shown in Figures 19 and 20, several issues with the prior known multiaxial constructions are addressed. First, density differences in the seam region are reduced in comparison to the prior multiaxial constructions due to the generally CD oriented yarns 1 16 (now oriented in the true CD) adjacent to the seam loops in the present fabric 100 extending in a true CD such that they can extend uncut across the width of the at least one material strip 110. In comparing Figure 15 to prior art Figure 11 , and Figure 19 to prior art Figure 13, the cut CD ends adjacent to the seam loops 14 result in yarn density differences along the CD width of the seam. Additionally, the prior art cut CD yarns 16 leave “pickets” which are loose ends that can protrude out from the base fabric 30 as the fabric loop is collapsed.

[0070] Additionally, as can be seen from a comparison of prior art Figure 13 to Figures 18 and 19 according to the present invention, the seam loop length of the seam loops 114 is more uniform as there is no (or minimal) sawtooth gap due to the pickets (cut CD yarn ends of the prior art) since in the present fabric 100, the generally CD oriented yarns extend in the true CD.

[0071] Further, as can be seen from a comparison of Figures 18 - 20 of the present invention to prior art Figures 10 - 13, the seam loops 114 are aligned straight and do not lean, allowing for easier seaming. Overall, this improves the properties of the base fabric 100 in the seam region while still maintaining the advantages of a multiaxial construction.

[0072] Further benefits of the present invention are the resistance to tension stretching of the seam loops 114 based on the true orientation of the seam loops 114 in the MD while the prior known multiaxial press felts typically have seam loops oriented at about 85° to 95° from the cross direction defined by the seam due to the spiral winding of the MD yarns which can result in stretching (see prior art Figures 8 and 9).

[0073] Having thus described the present invention in detail, it is to be appreciated and will be apparent to those skilled in the art that many physical changes, only a few of which are exemplified in the detailed description of the invention, could be made without altering the inventive concepts and principles embodied therein. It is also to be appreciatedthat numerous embodiments incorporating only part of the preferred embodiment are possible which do not alter, with respect to those parts, the inventive concepts and principles embodied therein. The present embodiment and optional configurations are therefore to be considered in all respects as exemplary and / or illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all alternate embodiments and changes to this embodiment which come within the meaning and range of equivalency of said claims are therefore to be embraced therein.

Claims

AMENDED CLAIMS received by the International Bureau on 19 February 2025 (19.02.2025)

1. A seamed industrial fabric, comprising: a base fabric formed from at least one material strip having a width that is less than a CD width of the base fabric, the at least one material strip including longitudinal edges that are bonded to adjacent ones of the longitudinal edges of the at least one material strip in order to define an overall base fabric width; the at least one material strip including generally MD oriented yarns that are held together relative to one another by an additional fabric material component, and the at least one material strip has cut ends that are joined along a CD join path in order to form a fabric loop with the generally MD oriented yarns being arranged in a true MD; the fabric loop is collapsed such that the MD oriented yarns are arranged in the base fabric as two superimposed layers joined by bent-back regions of the MD oriented yarns at CD oriented fold regions at each of the two opposing ends thereof, the additional fabric material component being removed from the MD oriented yarns in the CD oriented fold regions to form seam regions having seam loops formed of the MD oriented yarns extending in the true MD; and a pintle extending through a channel defined by intermeshing the seam loops from the two opposing ends to form a seam; wherein the at least one material strip is a spirally wound material strip, and the cut ends are realigned in order to arrange the generally MD oriented yarns of the spirally wound material strip in the true MD.

2. The seamed industrial fabric of claim 1 , further comprising batt material needled to at least one of an inner surface or an outer surface of the base fabric.

3. The seamed industrial fabric of claim 2, wherein the fabric is a press felt and the outer surface is a paper support surface.

4. The seamed industrial fabric of claim 1 , wherein the CD join path is located on an internal surface of the base fabric.

5. (Canceled).

6. The seamed industrial fabric of claim 1 , wherein the at least one material strip comprises a woven material, and the additional fabric material component comprises generally CD oriented yarns interwoven with the generally MD oriented yarns.

7. The seamed industrial fabric of claim 1 , wherein the seam regions each include at least one stuffer yarn located adjacent to the seam loops formed by the MD oriented yarns at the CD fold regions.

8. The seamed industrial fabric of claim 1 , wherein the generally MD oriented yarns include stacked generally MD oriented yarns.

9. A method of producing a seamed industrial fabric, the method comprising: forming a base fabric from at least one material strip including generally MD oriented yarns that are held together relative to one another by an additional fabric material component, the at least one material strip having a width that is less than a CD width of the base fabric by bonding adjacent longitudinal edges of the at least one material strip in order to define an overall base fabric width, the forming of the base fabric including spirally winding the at least one material strip to form a spirally wound material strip; cutting across the spirally wound material strip to form ends; realigning the ends which were cut such that the generally MD oriented yarns extend in the true MD; joining the ends of the at least one material strip along a CD join path in order to form a fabric loop with the generally MD oriented yarns being arranged in a true MD; collapsing the fabric loop such that the MD oriented yarns are arranged in the base fabric as two superimposed layers joined by bent-back regions of the MD oriented yarns at CD oriented fold regions at each of the two opposing ends thereof; removing the additional fabric material component from the MD oriented yarns in the CD oriented fold regions to form seam regions having seam loops formed of the MD oriented yarns extending in the true MD; andintermeshing the seam loops from the two opposing ends and inserting a pintle through the intermeshed seam loops to form a seam.

10. (Canceled).

11. The method of claim 9, further comprising needling batt material to at least one of an inner surface or an outer surface of the base fabric.

12. The method of claim 11 , wherein the seamed industrial fabric is a press felt and the outer surface is a paper support surface.

13. The method of claim 9, wherein the CD join path is located on an internal surface of the fabric.

14. The method of claim 9, wherein the at least one material strip comprises a woven material, and the additional fabric material component comprises generally CD oriented yarns interwoven with the generally MD oriented yarns.

15. The method of claim 14, wherein the generally CD oriented yarns adjacent to the seam loops extend in a true CD and extend uncut across the width of the at least one material strip.

16. The method of claim 9, further comprising inserting at least one stuffer yarn adjacent to the seam loops formed by the MD oriented yarns at the CD fold regions.

17. The method of claim 9, further comprising providing the at least one material strip with the generally MD oriented yarns with a stacked arrangement, and removing a portion of inner ones of the stacked MD oriented yarns in the seam regions.BRIEF STATEMENT UNDER PCT ARTICLE 19Pursuant to PCT Article 19, Applicant submits herewith an amendment to Claims 1 and 37. Applicant has amended each of independent Claims 1 and 9 to incorporate claims 5 and 10, respectively.RemarksThe Written Opinion indicates that claims 1-17 meet the PCT Requirements for novelty and industrial applicability. However, only claims 5 and 10 met the requirements for inventive step. The present amendment incorporates claim 5 into claim 1 , and cancels claim 5. Also, claim 9 has been amended to incorporate claim 10.Based on these amendments, claims 1 - 4, 6 - 9, and 11 - 17 should now meet the PCT requirements for novelty, inventive step, and industrial applicability.Respectfully submitted,

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