Abstract
A forming fabric tape for a machine for producing or processing a fiber web, the forming fabric tape including an upper fabric layer including upper longitudinal threads and upper transversal threads woven with the upper longitudinal threads; and a lower fabric layer including lower longitudinal threads and lower transversal threads woven with the lower longitudinal threads, wherein the upper fabric layer and the lower fabric layer are arranged above one another so that the upper fabric layer is oriented towards the fiber material web and the lower fabric layer is oriented away from the fiber web, wherein the upper fabric layer is connected with the lower fabric layer by binding threads (B1-B2) running in a transversal direction of the fabric tape, wherein a weaving pattern of the forming fabric tape is repeated in pattern repeats, wherein the pattern repeats are formed from plural longitudinal thread supergroups.
Claims
1. A forming fabric tape for a machine for producing or processing a fiber web, the forming fabric tape comprising: an upper fabric layer including upper longitudinal threads and upper transversal threads woven with the upper longitudinal threads; and a lower fabric layer including lower longitudinal threads and lower transversal threads woven with the lower longitudinal threads, wherein the upper fabric layer and the lower fabric layer are arranged above one another so that the upper fabric layer is oriented towards the fiber material web and the lower fabric layer is oriented away from the fiber web, wherein the upper fabric layer is connected with the lower fabric layer by binding threads running, in a transversal direction of the fabric tape, wherein a weaving pattern of the forming fabric tape is repeated in pattern repeats, wherein the pattern repeats are formed from plural longitudinal thread supergroups respectively including the upper longitudinal threads and the lower longitudinal threads, wherein each of the longitudinal thread super groups includes two first groups and a second group, wherein each first group) is formed respectively from an upper longitudinal thread and a lower longitudinal thread arranged below the upper longitudinal thread and each second group is formed respectively from an upper longitudinal thread and two lower longitudinal threads arranged below the upper longitudinal thread, wherein each binding thread in the pattern repeat forms at least one multiple binding with the upper transversal threads in the pattern repeat, and wherein the pattern repeat includes at least six longitudinal thread super groups that include the upper longitudinal threads and the lower longitudinal threads.
2. The forming fabric tape according to claim 1, wherein the pattern repeat includes exactly six longitudinal threads super groups including the upper longitudinal threads and the lower longitudinal threads.
3. The forming fabric tape according to claim 1, wherein the upper fabric layer is connected with the lower fabric layer in the pattern repeat exclusively by multiple bindings of the binding threads with the upper longitudinal threads.
4. The forming fabric tape according to claim 1, wherein a first binding thread in the pattern repeat forms two double bindings with the upper longitudinal threads, and wherein a second binding thread forms a double binding and a triple binding with the upper longitudinal threads.
5. The forming fabric tape according to claim 1, wherein the binding threads are always arranged in binding thread pairs, and wherein the two binding threads of a respective binding thread pair are woven in an alternating pattern with the upper longitudinal threads and the lower longitudinal threads and intersect in intersection points when switching from being woven with the upper longitudinal threads to being woven with the lower longitudinal threads.
6. The forming fabric tape according to claim 1, wherein the binding threads form a plain weave of the upper fabric layer with the upper transversal threads and the upper longitudinal threads.
7. The forming fabric tape according to claim 1, wherein the lower fabric layer includes a 6-shaft repeat binding of the lower longitudinal threads or a 8-shaft repeat binding of the lower longitudinal threads or a 12-shaft repeat binding of the lower longitudinal threads.
8. The forming fabric tape according to claim 7, wherein a lower transversal thread only switches over one or at the most two directly adjacent lower longitudinal threads and otherwise floats below the remaining lower longitudinal threads per shaft repeat of the lower longitudinal threads.
9. The forming fabric tape according to claim 1, wherein the upper longitudinal threads and the lower longitudinal threads in each group are not offset relative to each other in an orthogonal view of the fabric layers or only slightly offset relative to each other in the orthogonal view of the fabric layers so that a clear space of half a diameter of an upper longitudinal thread is formed at the most between the upper longitudinal threads and the lower longitudinal threads of each group or there is no free space.
10. The forming fabric tape according to claim 1, wherein a diameter of the lower longitudinal threads is greater than a diameter of the upper longitudinal threads.
11. The forming fabric tape according to claim 1, further comprising: more upper transversal threads than lower transversal threads.
12. The forming fabric tape according to claim 11, further comprising: 1.5 times an amount of upper transversal threads compared to an amount of lower transversal threads.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The invention is subsequently described based on advantageous embodiments with reference to drawing figures, wherein:
[0021] FIG. 1 illustrates a longitudinal thread super group that is used in webbing according to the invention;
[0022] FIG. 2 illustrates the longitudinal threads of a pattern repeat of the webbing according to the invention formed from six longitudinal thread super groups;
[0023] FIG. 3 illustrates a first embodiment of a run of a binding thread pair according to the invention;
[0024] FIG. 4 illustrates a second embodiment of a run of a binding thread pair according to the invention;
[0025] FIG. 5 illustrates a third embodiment of a run of a binding thread pair according to the invention;
[0026] FIG. 6 illustrates a first variant of the third embodiment of the invention according to FIG. 5 including a 6-shaft repeat binding of the lower longitudinal threads;
[0027] FIG. 7 illustrates a second variant of the third embodiment of the instant invention according to FIG. 5 including an 8-shaft repeat binding of the lower longitudinal threads;
[0028] FIG. 8 illustrates a third variant of the third embodiment of the instant invention according to FIG. 5 including a 12-shaft repeat binding of the lower longitudinal threads;
[0029] FIG. 9 illustrates a complete pattern repeat of the 8-shaft repeat binding of the lower longitudinal threads according to FIG. 7, and
[0030] FIG. 10 illustrates a complete pattern repeat of the 12-shaft repeat binding with respect to the lower longitudinal threads according to FIG. 8.
DETAILED DESCRIPTION OF THE INVENTION
[0031] FIG. 1 schematically illustrates a detail of the fabric tape according to the invention showing a longitudinal thread super group WE which can also be designated as a repeat unit WE including three upper longitudinal threads O1-O3 and four lower longitudinal threads U1-U4. These longitudinal threads are arranged in three groups, namely two first groups I which are respectively formed by an upper longitudinal thread O2-O3 and a lower longitudinal thread U3-U4 arranged below the upper longitudinal thread and a second group II that is formed by an upper longitudinal thread O1 and two lower longitudinal threads U1-U2 arranged below the upper longitudinal thread. Due to this specific arrangement of the longitudinal threads the upper longitudinal threads O1-O3 can be supported particularly well by the lower longitudinal threads U1-U4 which helps flatness of the upper fabric layer and thus reduces a propensity of the fabric tape to produce hydraulic markings. The upper fabric layer includes the upper longitudinal threads O1-O3 and upper transversal threads and thus transports and/or dries the fiber material web when the fabric tape is being used for producing the fiber material web. This positive effect with respect to the support of the upper longitudinal threads O1-O3 is already described in more detail in the printed document DE 10 2013 218 465A1 recited supra which is incorporated by reference regarding additional details.
[0032] The schematic representation of FIG. 1 shows the upper longitudinal threads O1-O3 centered precisely above the lower longitudinal threads U1-U4 of the respective groups. In practical applications, however, there can be some deviation. These deviations are caused by the fact that the longitudinal threads bind with the transversal threads and binding threads which can lead in particular to a movement to the left and to the right relative to the lower longitudinal threads in particular when using thinner upper longitudinal threads. Overall, however, these deviations are typically minor and do not render the individual groups in the fabric unrecognizable.
[0033] The fabric tape includes a weaving pattern that is repeated in pattern repeats R according to the invention. The pattern repeat R is formed from at least six longitudinal threads super groups with respect to the upper longitudinal threads and the lower longitudinal threads of the fabric tape. In particular, the pattern repeat can be formed from precisely six longitudinal thread super groups WE as schematically illustrated in FIG. 2. Thus, the pattern repeat R includes 63=18 upper longitudinal threads and 64=24 lower longitudinal threads, thus in total 42 longitudinal threads.
[0034] Since the pattern repeat R includes at least six, advantageously exactly six longitudinal thread super groups WE, each binding thread B1, B2 according to the invention can form at least one multiple binding with the upper longitudinal threads in the pattern repeat R and the binding threads B1, B2 can continue a plain weave of the upper fabric layer in pairs without rendering the fabric tape too thick. Corresponding embodiments for the path of the binding threads B1-B2 are schematically illustrated in FIGS. 3-5. Thus, the upper longitudinal threads are pulled down less compared to fabric tapes where the binding threads only form single bindings with the upper longitudinal threads so that depressions in the upper fabric layer are prevented or at least reduced. Since the binding threads contribute to the plain weave in the upper fabric layer in pairs, the upper fabric layer can support the fiber material web transported and/or dried thereon particularly well.
[0035] FIG. 3 illustrates a first embodiment of the invention with respect to the binding threads B1, B2 showing the upper and lower longitudinal threads of the six longitudinal thread super groups WE in the pattern repeat R like in FIG. 2. Additionally an upper transversal thread OQF from the pattern repeat R is shown which is run in an alternating pattern below and above adjacent upper longitudinal threads in order to form a plain weave in the upper fabric layer. Furthermore, the path of a first binding thread B1 and a second binding thread B2 is shown in sections where the path is part of the upper fabric layer. The two binding threads B1, B2 form a binding thread pair that is directly adjacent to the upper transversal thread OQF wherein the binding thread pair also contributes to the plain weave of the upper fabric layer since each second upper longitudinal thread is bound by one of the two binding threads B1, B2, thus the respective binding thread B1, B2 runs above the upper longitudinal thread, whereas this does not apply to the other upper longitudinal threads arranged there between. In the instant embodiment according to FIG. 3, the dashed first binding thread B1, forms a quadruple binding with the upper longitudinal threads of the pattern repeat R, this means the first binding thread B1 that switches from a bottom left from the lower fabric layer into the upper fabric layer is run overall above four upper longitudinal threads before switching to the bottom right into the lower fabric layer. On the other hand side the dash-dotted second binding thread B2 forms a quintuple binding with the upper longitudinal threads of the pattern repeat R, this means the second binding thread switching from the left from below from the lower fabric layer into the upper fabric layer is run overall over five longitudinal threads before switching to the bottom right into the lower fabric layer again. This embodiment is characterized in that the upper longitudinal thread are hardly pulled down by the binding threads B1, B2 so that excellent flatness of the upper fabric layer can be achieved.
[0036] However, this embodiment is not necessarily optimum with regard to strength of the connection of the upper fabric layer with the lower fabric layer through the binding threads B1, B2. This is caused by the fact that this embodiment provides only very few switches of the binding threads B1, B2 from the upper fabric layer into the lower fabric layer in the pattern repeat R.
[0037] In order to increase strength of the connection between the two fabric layers it is advantageous to let the binding threads B1, B2 switch in the pattern repeat from the upper fabric layer into the lower fabric layer more often. The second embodiment according to FIG. 4 shows a rather large number of these switches. Subsequently only differences over the first embodiment according to FIG. 3 are addressed and otherwise the description of the first embodiment is being referred to. The same applies accordingly for the additional embodiments. Differently from the first embodiment, the first binding thread B1 and the second binding thread B2 do not only switch from the lower fabric layer into the upper fabric layer once in the pattern repeat R but switch three times respectively. Accordingly, the connection between the two fabric layers is stronger. In return the number of bindings is reduced. Thus, the first binding thread B1 in the pattern repeat R forms a single binding with the second upper longitudinal thread counted from the left and forms a first double binding with the 6.sup.th and the 8.sup.th upper longitudinal thread and forms a second double binding with the 12.sup.th and the 14.sup.th upper longitudinal thread whereas the second binding thread B2 forms a first single binding with the 4.sup.th upper longitudinal thread, a second single binding with the 10.sup.th upper longitudinal thread and a double binding with the 16.sup.th and 18.sup.th upper longitudinal thread. In particular, the upper longitudinal threads of the single binding, thus the second, fourth and tenth upper longitudinal thread are pulled down rather strongly by the binding threads B1, B2 since these upper longitudinal threads switch directly before from the lower fabric layer into the upper fabric layer and directly thereafter back again into the lower fabric layer. This is not optimum with respect to flatness of the upper fabric layer.
[0038] The embodiment according to FIG. 5 shows a balanced compromise between sufficient strength of the connection of the upper fabric layer at the lower fabric layer on the one hand side and avoiding depressions in the upper fabric layer caused by the single bindings. In this embodiment the two binding threads B1, B2 respectively switch two times per pattern repeat from the lower fabric layer into the upper fabric layer. Thus, single bindings are completely prevented. Therefore, the first binding thread B1 in the pattern repeat R forms a first double binding with the second and fourth upper longitudinal thread and a second double binding with the 10.sup.th and 12.sup.th upper longitudinal thread, whereas the second binding thread forms a double binding with the 6.sup.th and 8.sup.th upper longitudinal thread and a triple binding with the 14.sup.th, 16.sup.th, and 18.sup.th upper longitudinal thread.
[0039] Three different variants of the third embodiment illustrated in FIG. 5 are schematically illustrated in FIGS. 6-8. The three variants different from each other with respect to number of shafts of the lower longitudinal threads. In the first variant according to FIG. 6 the lower fabric layer has a 6 shaft repeat binding with respect to the lower longitudinal threads. Therefore, the weaving pattern of the lower fabric layer that is defined by the lower longitudinal threads and the lower transversal threads is always repeated after six lower longitudinal threads with respect to the respective lower transversal thread UQF. As illustrated in FIG. 6, the lower transversal thread UQF can run over the 7.sup.th, 13.sup.th, and 19.sup.th lower longitudinal thread in the pattern repeat R and can otherwise float below the remaining lower longitudinal threads. These flotations of the lower transversal thread UQF represent a wear volume for a machine side of the fabric tape oriented away from the fiber material web when the fabric tape is being used.
[0040] In the second variant according to FIG. 7, the lower fabric layer has an 8-shaft repeat binding with respect to the lower longitudinal threads. Therefore, the weaving pattern of the lower fabric layer which is defined by the lower longitudinal threads and the lower transversal thread always repeats after 8 lower longitudinal threads with respect to a respective lower transversal thread UQF. As illustrated in FIG. 7, the lower transversal thread UQF can run above the first, ninth, and 17.sup.th lower longitudinal thread in the pattern repeat R, and can otherwise float under the remaining lower longitudinal threads. These flotations of the lower transversal thread UQF represent a wear volume for the machine side of the fabric tape that is oriented away from the fiber material web when the fabric tape is being used as. Compared to the first variant according to FIG. 6, the flotations are longer in total so that more wear volume can be provided.
[0041] In the third variant according to FIG. 8, the lower fabric layer has a 12-shaft repeat binding with respect to the lower longitudinal threads. This has the effect that the weave of the lower fabric layer which is defined by the lower longitudinal threads and the lower transversal threads, repeats after 12 lower longitudinal threads with respect to a lower transversal thread UQF. As illustrated in FIG. 8 the lower transversal thread UQF can run over the first and second and over the 13th and 14th lower longitudinal thread in the pattern repeat R and can otherwise float below the remaining lower longitudinal threads. These flotations of the lower transversal thread UQF represent a wear volume for the machine side of the fabric tape that is oriented away from the fiber material web when operated. Compared to the first variant according to FIG. 6 and the second variant according to FIG. 7, the flotations are longer in total so that more wear volume can be provided.
[0042] FIG. 9 schematically illustrates the complete weave of a pattern repeat of the second variant illustrated in FIG. 7 having the 8-shaft repeat binding with respect to the lower longitudinal threads showing 8 pairs of a respective upper transversal thread and a lower transversal thread switching above one another and 8 pairs respectively including two binding threads which are shown in dashed lines and how these run above the upper and lower longitudinal threads. Since each pair of two respective binding threads completes the weaving pattern of the upper fabric layer together with the upper transversal threads and the lower longitudinal threads to form a plain weave the respective pair of binding threads can be counted as one upper transversal thread. According to this count, the fabric tape has twice the number of upper transversal threads compared to the lower transversal threads.
[0043] FIG. 10 schematically illustrates the complete weaving pattern of a pattern repeat of the third variant illustrated in FIG. 8 and shows the 12-shaft repeat binding of the upper longitudinal threads, showing the 12 pairs respectively including an upper transversal thread and a lower transversal thread above one another in an alternating pattern and the 12 pairs respectively including 2 binding threads, one of them shown in dashed lines and how these run above an below the upper and lower longitudinal threads.
REFERENCE NUMERALS AND DESIGNATIONS
[0044] B1, B2 first binding thread, second binding thread [0045] O1-O3 upper longitudinal threads of longitudinal thread super group [0046] OQF upper transversal thread [0047] R pattern repeat of a weaving pattern of the fabric tape according to the invention [0048] U1-U4 lower longitudinal threads of a longitudinal thread supergroup [0049] UQF lower transversal thread [0050] WE longitudinal thread super group or repeat unit
