BASIC STRUCTURE OF A GARMENT FOR A MACHINE TO PRODUCE OR PROCESS A FABRIC OF FIBROUS MATERIAL AND A METHOD FOR THE PRODUCTION THEREOF
Patent Information
- Authority / Receiving Office
- MX · MX
- Patent Type
- Patents
- Current Assignee / Owner
- VOITH PATENT GMBH
- Filing Date
- 2022-02-02
- Publication Date
- 2026-05-19
Smart Images
Figure MX433864B0
Abstract
Description
The invention relates to the basic structure of a garment for a machine for producing or processing a fabric of fibrous material according to the pre-characterization clause of claim 1, to a garment according to the pre-characterization clause of claim 9, and to a method for producing a basic structure according to the pre-characterization clause of claim 10. Garments for paper machines or similar equipment often have a basic structure that provides stability and withstands the forces, particularly tensile forces, that act on the garment during equipment operation. A large proportion of the basic structures used today consist entirely or partially of woven fabrics. A conventional method for producing the required endless fabric loops is circular knitting. In this case, the endless structure is produced directly within the loop itself and is seamless. However, circular knitting is very slow and is used as a production method. Furthermore, it is essential to know precisely during knitting the desired length of the garment. Since each position on a paper machine requires a very specific length of garment loop, the production of such basic structures is only possible to order. As an alternative that overcomes these two difficulties, it was proposed some time ago to produce seamless garments using plain-woven fabrics. These are described, for example, in EP 0 425 523 or EP 2 788 545. In this case, the ends of the plain-woven fabric are folded to form a two-layer textile. The pleat locations can be created by removing CD threads that correspond to the weft threads in the loop—to create sewing loops. The two front ends of the double-layer textile can be joined by means of interlocking sewing loops connected by a pin wire. This concept has proven highly successful in recent years because it allows for the rapid production of flat-woven fabrics and their storage on rolls. When an order is placed, the desired length is removed from the rolls and then cut to the required width. For some applications, however, this concept proved disadvantageous because it is relatively inflexible. The two layers of the two-ply textile consist of the same woven fabric. This leads, on the one hand, to the so-called Moiré effects due to overlapping. On the other hand, the different requirements of the back and paper sides cannot be taken into account. To avoid these problems, document DE102016111769 proposes modifying the weave pattern of the flat nonwoven fabric during the weaving process, so that the two layers of the two-ply textile have different weave patterns. Although the moiré effects can therefore be reduced, the change in weave pattern must take place at the fold, so the garment length must be known beforehand during the production of the basic structure. Therefore, one objective of the present invention is to overcome the problems of the prior art. In particular, one objective of the present invention is to provide a basic structure and its method of production, which allows both great flexibility in the design of the garment and the components of which nevertheless are available to be produced substantially independently of the dimensions of the garment. These objectives are fully achieved by means of a basic structure in accordance with the characterizing part of claim 1 and by means of a method for producing a basic structure in accordance with the characterizing part of claim 10. The advantageous modalities are described in the dependent claims. With regard to the basic structure, the objective is achieved by means of a basic garment structure for a machine for producing or processing a network of fibrous material, in particular paper, cardboard, or woven netting. The basic structure comprises at least one flat woven fabric of type A and a second flat woven fabric of type B.The basic structure is characterized in that it further comprises two loop elements, these loop elements respectively formed from a portion of flat woven fabric having a first section of woven fabric of type A and a second section of woven fabric of type B, and wherein the first section is placed in the second section such that the place of the fold is formed at a distance of less than 5cm, in particular less than 1cm, from the place of change between woven fabric of type A and woven fabric of type B, and wherein the two flat woven fabrics are arranged one on top of the other and the two loop elements are respectively arranged at a front end. The basic structure, therefore, comprises at least four elements. The first and second flat-woven fabrics in this case usually constitute the majority of the basic structure. They are configured substantially as a homogeneous woven fabric and advantageously can be produced as a roll commodity regardless of the dimensions of the future garment, and are cut accordingly from the roll during garment production. The change between woven fabrics of type A and woven fabrics of type B in the basic structure takes place at the fold, as in document DE102016111769. In contrast to this prior art, the basic structure of the present invention comprises its own loop element, at which the fold occurs. These loop elements are substantially independent of the length of the final garment and can be produced and stored in standardized formats. Therefore, the basic structure can be produced from elements that can be pre-produced either as rolled merchandise or as standardized loop elements. However, the invention allows the flexibility to produce the two-layer textile using different types of woven fabrics. Moiré effects can therefore be avoided or at least reduced, and the different requirements on the paper side and the back side can be taken into account. As described, to form a loop element, a portion of flat woven fabric is folded. A fold is therefore formed at one end of the loop element. The two front edges of the original flat woven fabric portion come to rest at the other end of the loop element. In this case, one front edge is a woven fabric of type A and the other front edge is a woven fabric of type B. The first and second sections in this case can be the same length. However, it is often advantageous for these two sections to have different lengths. The preferred length ratio is 40% / 60% and 30% / 70%. For example, in the case of a piece of plain woven fabric that is 2m long, the first section could be 1.20m long and the second section could be 0.80m long. The different lengths have the advantage that the front edges do not rest directly on each other in the future fold, but are offset. Plain woven fabrics and portions thereof are commonly used to create fabrics made of yarns that consist entirely or partially of a polymer material. Polyamides, polyesters, and polyethylenes are typical examples. It is particularly advantageous that in the first loop element and / or the second loop element, the front edge of the woven fabric of type A is connected, in particular i Qé Lnn / zznz / E / YiA welded, to the first flat woven fabric and the front edge of the woven fabric of type B is connected, in particular welded, to the second flat woven fabric. Connecting the loop elements to the first and second flat-knitted fabrics creates a continuous basic structure. This facilitates further garment formation. Furthermore, this basic structure not only provides lateral stability but also resists tensile forces. It is very convenient in this type of connection, exclusively for woven fabrics of type A, to be present on one side of the basic structure and exclusively for woven fabrics of type B, to be present on the other side. Such a connection is also referred to as a bond. To achieve a basic structure and a garment with properties that are as homogeneous as possible, it is usually useful for properties such as permeability or thickness in the bond region to substantially match the external properties of the connection zone, so that they are particularly in the range between 80% and 120% of the corresponding external values of the connection zone. The possibilities for producing such bonds are described, for example, in WO 2019 / 063518. Furthermore, in the region of the fold locations of the loop elements, the CD threads can be advantageously removed to form sewing loops, in particular 3 to 8 CD threads are removed per fold location. If such stitching loops are formed on both sides of the two-layer textile, they can be fed one inside the other and connected by means of a bolt wire so that the basic structure, or the entire garment, can be made endlessly. To allow simple spinning of the bolt wire, the internal diameter of the stitching loops should ideally be as large as possible. To determine the inner diameter of a sewing loop, the largest circle that can be inserted into the sewing loop is determined. The diameter of this circle is then considered the inner diameter of the sewing loop. However, a very large diameter leads to a very thick stitching loop that can potentially leave marks on the fibrous material. It has been found that the inner diameter of the stitching loop is advantageously between 0.8 mm and 2.2 mm, preferably between 1 mm and 1.6 mm. The size of the internal diameter of the stitching loop is primarily influenced by the number of CD threads removed to form the stitching loops. Advantageously, the internal diameter described is usually achieved simply by removing 3-8 CD threads. When only one or two CD threads are removed, the stitching loop will have a smaller diameter in many applications. When more than 8 threads are removed, the risk of the stitching loop diameter being too large increases. The inner diameter of the loop also depends on the diameter of the flat yarn in the MD yarns. The range [0.8–2.2 mm] in this case is particularly applicable to MD yarns with a diameter between 0.3 mm and 0.6 mm. Such MD yarns are typical for basic woven fabrics used in paper machine garments. With different diameters of flat yarns, inner loop diameters outside the specified range are also possible. Furthermore, it can be advantageous to use CD yarns (special yarns), which are neither Type A nor Type B woven fabrics, directly near the stitching loops. These special yarns can be either woven within the woven fabric portion or added subsequently during the formation of the stitching loops. Since the location of the stitching loop on the future loop element is already established by the loop elements when the flat woven fabric portion is made—that is, at the transition between Type A and Type B woven fabric—it is possible to weave the special yarns during the production of the flat woven fabric portion. Examples of possible special yarns include cords, multifilaments, or yarns with a non-round cross-section, such as flat yarns. Special yarns can also be provided in the form of absorbent yarns.In particular, special yarns can correspond in material and shape to other CD yarns of the woven fabric type, but with corresponding modifications, such as the addition of a light-absorbing additive for a specific wavelength range—particularly in a section of the NIR range between 780 nm and 1200 nm. Such absorbent CD yarns can be welded to MD yarns using laser transmission welding. This provides a degree of stability to the stitched loops. Since MD yarns—particularly those made of polyimide—do not absorb laser light, they are heated during welding only through contact with the CD yarns. In this way, their strength is not substantially compromised. Alternatively or in addition, such special yarns can also be provided in other locations on the flat nonwoven fabric portions or loop elements. Such special yarns in the form of absorbent yarns can be highly advantageous, particularly in or within the immediate vicinity of the front edges. In this way, the connection of the loop elements to the flat woven fabrics by welding can be simplified. Again, it has been advantageously proven that the location where the joining connection will occur is already known for the stitching loop during the weaving of the flat woven fabric portions. The special yarn—usually more expensive—therefore needs to be woven only in the locations where it is required. A fabric woven by weaving or otherwise provides individual brand yarns or other special yarns - in particular less than 10 - within a woven fabric of type A (or B) in this case should still be considered as a woven fabric of type A (or B). Advantageously, it can be shown that the woven fabrics of types A and B can differ in at least one parameter, in particular, in a different weave pattern or a different yarn density (CD). This allows for particularly high flexibility in garment design. However, it is not absolutely necessary. In alternative embodiments, it can also be provided that the woven fabrics of type A are the same as the woven fabrics of type B. Such basic structures are also possible according to one aspect of the present invention. In many forms, it may be advantageous for the basic structure to comprise a variety of flat woven fabrics of type A and / or a variety of flat woven fabrics of type B. In particular, a basic structure can be formed from six elements, namely, two flat woven fabrics of each of the types of woven fabric A and B and two loop elements. Preferably, it can be provided that the woven fabric of type A and / or the woven fabric of type B have an MD yarn density of between 30% and 45%, particularly between 34% and 42%, especially between 36% and 40%. Ideally, both types of woven fabric should have either completely or substantially the same MD yarn density. This is advantageous in terms of production technology. For example, the plain weave fabric for looped elements can be produced in a loop, and both types of woven fabric can use the same warp yarns, which then provide the MD yarns in the basic structure. At the point where the two types of woven fabric change, the weave pattern or the weft yarn material can be modified relatively easily. Modifying the weft yarns, however, is only possible with considerable difficulty. Furthermore, the stitching loops formed by MD yarns at the pleat locations can therefore be more easily inserted into one another, so that the basic structure can be more easily made without overlocking. i Qfr Lnn / zznz / E / YiA Yarn density (MD) specifies the proportion of the width of the woven fabric that is taken up by the yarns (MD). For example, if 8 threads per cm are provided and a thread has a diameter of 0.4mm, the thread density is (8*0.4) / 10 = 32%. The specified MD yarn density range allows, on the one hand, for a reasonably simple supply of stitching loops within one another. It should be noted that in this stitching region, the MD yarns of the two stitching loops carry a loop density that corresponds to twice the MD yarn density. With an MD density of 45%, this gives a loop density of 90%. This is already close to the theoretical maximum density of 100%. Loop densities even greater than 90% can only be handled with great difficulty and are therefore not advantageous. An MD yarn density of less than 30%, on the other hand, is not critical in terms of loop density. However, the properties of the woven fabric, for example, tensile strength, usually suffer so much that the value should not fall below this level without risking other disadvantages. Garments for paper or pulp machines, and their basic structures, are often subjected to heat treatment in a process called temperature control. Usually, the warp yarn density in the finished garment or basic structure is higher than the density before temperature control due to the resulting shrinkage. The specified ranges for MD yarn density are advantageous for the garment before and after temperature control in this case. With respect to the garment, the objective is achieved by means of a garment, in particular a sewing felt, for a machine for producing or processing a network of fibrous material, in particular a paper, cardboard or woven net, wherein the garment comprises at least one basic structure in accordance with an aspect of the invention. The garment may also include additional components. Often, the garment is also designed with additional elements, such as non-woven overlays, woven components, film, or foam. This depends on the intended use of the garment as assembled. One or more layers of nonwoven fibers may be provided, particularly on one side of the garment that is in contact with the fibrous material. They may also be provided on the back side of the nonwoven fibers. Nonwoven fibers are usually attached to the basic structure by means of needle punching. This is particularly advantageous since the individual components i Qfr Lnn / zznz / E / YiA of the basic structure are therefore also connected to each other, thus further increasing the strength of the garment. With respect to the method, the objective is achieved by means of a method for producing a basic structure in accordance with an aspect of the invention, wherein the method comprises the following steps: a) provide a first flat woven fabric of type A woven fabric and a second flat woven fabric of type B woven fabric, b) provide two portions of plain woven fabric, having a first section of woven fabric of type A and a second section of woven fabric of type B, and forming loop elements by placing the first section in the second section so that the place of the pleat is formed at a distance of less than 5cm, in particular less than 1m, from the place of change between woven fabric of type A and woven fabric of type B, and c) arrange the first flat woven fabric and the second flat woven fabric above one on top of the other and the two loop elements respectively at a front end. In advantageous modalities, the method may also include the step: d) connect the loop elements to the first flat woven fabric and the second flat woven fabric in such a way that in the first and second loop element, the front edge of the woven fabric of type A is connected, in particular welded, to the first flat woven fabric and the front edge of the woven fabric of type B is connected, in particular welded, to the second flat woven fabric. When carrying out the method, it should be noted that the order of the steps can be optionally interchanged. For example, the connection of the loop elements, or of the portions of flat woven fabric, to the first / second flat woven fabric is possible before folding and forming the subsequent loop elements. Furthermore, one or more heat control steps are provided in advantageous versions of the method. Many variations can be considered here. For example, the first flat woven fabric may be subject to heat control before and / or after the arrangement in step a). In addition or as an alternative, the second flat woven fabric may be subject to heat control before and / or after the arrangement in step a). In addition or as an alternative, the portions of flat woven fabric from which the loop elements are formed can also be subject to heat control before and / or after the arrangement in step b). For example, it may be advantageous for the woven fabric of the flat woven fabric portions i Qfr Lnn / zznz / E / YiA to be pre-produced in the form of roll merchandise and these roll merchandise are already subject to heat control, i.e., before separating the individual portions of flat woven fabric. The additional advantageous features of the invention will be explained with the help of exemplary embodiments with reference to the schematic figures. Figures 1a and 1b show a portion of flat woven fabric, or a loop element, in accordance with an aspect of the invention Figure 2 shows a basic structure in accordance with one aspect of the invention Figure 2a shows a basic structure in accordance with a further aspect of the invention Figure 3 shows a woven fabric for use in a method in accordance with a further aspect of the invention. The figure shows a portion of plain woven fabric 6 that can be used as a basis for producing a loop element 2. The portion of plain woven fabric 6 consists of a first section 6a, which is fabric of type A, and a second section 6b, which is woven fabric of type B. The woven fabric of type A and the woven fabric of type B can be advantageously provided in that they differ in at least one parameter, in particular a different weave pattern or a different yarn density CD. In terms of production technology, it is highly advantageous for the two types of woven fabric to have the same yarn density MD. Sometimes, it can also be provided that the woven fabric of type A is the same as the woven fabric of type B. To allow for high flexibility in the production of basic structures 1, or garments, the flat-knitted fabric portion should be short in MD – compared to the basic structure. In particular, the flat-knitted fabric portion 6 can be configured to be shorter than 5m, preferably 2m or shorter. The first section 6a and the second section 6b in this case can have the same length. However, it is often advantageous for these two sections 6a and 6b to have different lengths. The length range is preferably between 40% / 60% and 30% / 70%. In the case of a portion of plain woven fabric 6 having a length of, for example, 2 m, the first section 6a could be 1.20 m long and the second section 6b could be 0.80 m long. The different lengths have the advantage that the front edges 3a, 3b do not rest directly on each other in the future fold, but are offset. To form a loop element 2 from a portion of woven fabric 6, the portion of woven fabric can be folded and placed on itself. This is shown in Figure 1b. The fold location 4 in this case is located in the region of the change point 60, specifically at change point 60. To form sewing loops 5, which serve to make the subsequent basic structure 1, or the garment, endless, the CD threads can be removed at the fold location. Often, it is sufficient to remove between 3 and 8 CD threads. The CD threads can be removed from both type A and type B woven fabric. If, for example, removal from one type of woven fabric is more complicated than from the other, however, it is also possible to remove the CD threads from only one type of woven fabric.If, as depicted in Figure Ib, the two sections 6a, 6b have different lengths, the front edges 3a, 3b do not rest on each other, which may be advantageous for subsequent further processing. The two layers of loop element 2 can be advantageously connected to each other. Such a connection can, for example, be made using one or more connections 7. Such a connection or stitching is advantageous, among other things, because the two layers of loop element 2 cannot be displaced relative to each other during further processing. The connection in the region of the sewing loop 5, for example at a distance of less than 2 cm from the sewing loop 5, can be advantageous to fix the sewing loop 5 and subsequently allow easier insertion of the two sewing loops 5 into each other to make the basic structure 5 endless. Figure 2 shows a basic structure 1 according to an aspect of the invention. This basic structure is formed from a first flat woven fabric 10 of type A woven fabric and a second flat woven fabric 20 of type B woven fabric, also as two loop elements 2a, 2b. The loop elements 2a, 2b in particular can be configured as described in Figures 1a, 1b. The first flat-knitted fabric 10 and the second flat-knitted fabric 20 are arranged one on top of the other in this case. In a similar way for the loop elements 2, 2a, 2b, these two layers 10, 20 can be connected, in particular sewn, to each other. These sewn connections 7 are not explicitly represented in Figure 2, but they may nevertheless be present. To form a continuous basic structure 1, the four components in the figure are connected to one another. In this case, in loop elements 2a and 2b, the front edge 3a of the woven fabric of type A is connected to the first flat woven fabric 10, and the front edge 3b of the woven fabric of type B is connected to the second flat woven fabric 20. Connection 8, in particular i Qfr Lnn / zznz / E / YiA, can be made in the form of a welded seam 8. The welding can be carried out, for example, by laser welding, in particular by laser transmission welding, or by ultrasonic welding. Alternatively, connection 8 can be made as an adhesive or sewn connection. The basic structure 1 formed in this way has two stitching loops 5a, 5b. By inserting these stitching loops 5a, 5b one inside the other and subsequently inserting the pin wire, the basic structure 1 can be made endlessly. Often, before (or after) making it endless, the basic structure 1 is also provided with additional elements, for example, non-woven overlays, additional woven elements, films, or foam elements. This depends on the intended use of the garment formed in this way. While a basic structure 1 consists of four woven elements, as depicted in Figure 2, is generally advantageous, it is possible and provided for the basic structure to be constructed from more elements. An example of this is shown in Figure 2a. Basic structure 1 differs from the basic structure in Figure 2 in that, in addition to the first flat-woven fabric 10 and the second flat-woven fabric 20, it comprises an additional first flat-woven fabric 11 and an additional second flat-woven fabric 21. The two respective flat-woven fabrics of the same type can also be connected to each other in a suitable manner, for example, by means of a welded seam 8a. This can be advantageous, for example, if the flat-woven fabric is not in the form of an almost endless commodity, but rather of prefabricated portions of woven fabric of a fixed length.In such case, in addition to the first (second) plain woven fabric 10 (20) and the additional first (second) plain woven fabric 11 (21), even more plain woven fabrics may also be required in a similar manner to build the basic structure in this way. With reference to the example in Figure 3, one of the advantages of the garment, in accordance with an aspect of the invention, will be explained again. By separating the loop elements 2, 2a, 2b from the plain woven fabric 10, 20, it is possible to produce these woven parts of the basic structure 1 without needing to know the dimensions of the future garment required. In this respect, Figure 3 shows a woven fabric, with the weft direction of the loom corresponding to the CD direction of the future garment, and the warp direction to the MD direction. In the CD direction, the woven fabric can be produced with the maximum width of the available loom, so as to meet all the width requirements of the future garment as much as possible. If smaller garments are desired, this can be achieved by cutting accordingly.Therefore, the difficulty created also occurs in current production methods, and does not represent a specific disadvantage of the present concept. In direction MD, the woven fabrics of type A and B alternate in a regular pattern. This is based on the length of the flat-woven fabric portions 6 subsequently required for the loop elements, along with the desired length interval of the woven fabrics of types A and B. For example, the flat-woven fabric portions 6 can be 2m long, the first section 6a has a length of 1.2m, and the second section 6b has a length of 80cm. The flat-woven fabric portions 6 and sections 6a and 6b can be longer or shorter. In each case, the woven fabric of Figure 3 can be pre-produced as a roll commodity with the regular alternation of the type A and B weaves. To produce a basic structure 1, two flat-woven fabric portions 6 can be taken from this roll, and the loop elements 2, 2a, and 2b can be formed there.The length required for the specific order, or basic structure 1, can then be independent of the loop elements by means of a suitable length of the first flat woven fabric 10 and the second flat woven fabric 20. I heard? Lnn / zznz / E / YiA Reference List i Qé Lnn / zznz / E / YiA basic structure, 2a,2b loop element 3a,3b front edge fold location sewing loop portion of flat woven fabric 6th first section 6b second section sewn connection weld seam, 11 first flat woven fabric, 21 second flat woven fabric change location
Claims
1. A basic structure for a machine for producing or processing a network of fibrous material, in particular paper, cardboard, or woven netting, comprising at least a first flat woven fabric of type A and a second flat woven fabric of type B, characterized in that the basic structure further comprises two loop elements, the loop elements being formed from a portion of flat woven fabric having a first section of type A and a second section of type B, and wherein the first section is positioned on the second section such that the place of the pleat is formed at a distance of less than 5 cm, in particular less than 1 cm, from the change of position between the type A and type B woven fabric.and wherein the first flat-woven fabric and the second flat-woven fabric are arranged one on top of the other and the two loop elements are arranged respectively at a front end.
2. The structure as claimed in claim 1 characterized in that in the first loop element and / or the second loop element, the first front edge of the woven fabric of type A is connected, in particular welded, to the first flat woven fabric, and the front edge of the woven fabric of type B is connected, in particular welded, to the second flat woven fabric.
3. The basic structure as claimed in one of the preceding claims, characterized in that in the region of the fold locations of the loop elements, the CD threads are removed to form sewing loops, in particular 3 to 8 CD threads are removed per fold location.
4. The basic structure as claimed in claim 3, characterized in that the CD threads (special threads), which are not in the woven fabric of type A nor in the woven fabric of type B, are provided in close proximity to the sewing loops.
5. The basic structure as claimed in one of the preceding claims, characterized in that the woven fabric of type A is the same as the woven fabric of type B.
6. The basic structure as claimed in any one of claims 1 to 4 characterized in that the woven fabrics of type A and B differ in at least one parameter, in particular a different weaving pattern or a different yarn density CD.
7. The basic structure as claimed in one of the preceding claims, characterized in that the basic structure comprises a variety of flat woven fabrics of type A and / or a variety of flat woven fabrics of type B.
8. The basic structure as claimed in one of the preceding claims, characterized in that the woven fabric of type A and / or the woven fabric of type B have a yarn MD density of between 30% and 45%, in particular between 34% and 42%.
9. A garment, in particular a sewing felt, for a machine for producing or processing a network of fibrous material, in particular paper, cardboard or woven netting, characterized in that the garment comprises at least one basic structure as claimed in one of the preceding claims.
10. A method for producing a basic structure as claimed in any one of claims 1 to 8, wherein the method comprises the steps: a) providing a first flat woven fabric of type A and a second flat woven fabric of type B, b) providing two portions of flat woven fabric, each having a first section of type A and a second section of type B, and forming loop elements by placing the first section on the second section so that the pleat location is formed at a distance of less than 5 cm, in particular less than 1 cm, from the changeover location between type A and type B woven fabric, and c) arranging the first flat woven fabric and the second flat woven fabric one on top of the other and the two loop elements respectively at a front end.
11. The method as claimed in claim 10, characterized in that the method further comprises the step: d) connecting the loop elements to the first flat woven fabric and to the second flat woven fabric such that, in the first loop element and the second loop element, in each case the front edge of the woven fabric of type A is connected, in particular welded, to the first flat woven fabric and the front edge of the woven fabric of type B is connected, in particular welded, to the second flat woven fabric.