Papermaker's forming fabric with cross-direction yarn stitching and ratio of top machined direction yarns to bottom machine direction yarns of less than 1
View Patent ↗A triple layer papermaker's fabric includes: a set of top MD yarns; a set of top CMD yarns interwoven with the top MD yarns to form a top fabric layer; a set of bottom MD yarns; a set of bottom CMD yarns interwoven with the bottom MD yarns to form a bottom fabric layer; and a set of stitching yarn pairs that interweave with the top MD yarns, wherein at least one of the yarns of each stitching yarn pair interweaves with the bottom MD yarns. The top MD yarns and the top CMD yarns are interwoven in a series of repeat units and the bottom MD yarns and the bottom CMD yarns are interwoven in a series of corresponding repeat units. The set of top MD yarns comprises a first number of top MD yarns in each repeat unit, and the set of bottom MD yarns comprises a second number of bottom MD yarns in each repeat unit, wherein the second number being greater than the first number. Each bottom MD yarn follows a different interweaving pattern than that followed by each of its two immediate neighboring bottom MD yarns.
1. A triple layer papermaker's fabric, comprising:
a set of top machine direction (MD) yarns;
a set of top cross machine direction (CMD) yarns interwoven with the top MD yarns to form a top fabric layer;
a set of bottom MD yarns;
a set of bottom CMD yarns interwoven with the bottom MD yarns to form a bottom fabric layer; and
a set of stitching yarn pairs that interweave with the top MD yarns, wherein at least one of the yarns of each stitching yarn pair interweaves with the bottom MD yarns;
wherein the top MD yarns and the top CMD yarns are interwoven in a series of repeat units and the bottom MD yarns and the bottom CMD yarns are interwoven in a series of corresponding repeat units;
wherein the set of top MD yarns comprises a first number of top MD yarns in each repeat unit, and the set of bottom MD yarns comprises a second number of bottom MD yarns in each repeat unit, and wherein the second number is greater than the first number; and
wherein each bottom MD yarn follows a different interweaving pattern than that followed by each of its two immediate neighboring bottom MD yarns.
2. The triple layer papermaker's fabric defined in claim 1 , wherein a stitching yarn pair is positioned between each adjacent pair of top CMD yarns.
3. The triple layer papermaker's fabric defined in claim 1 , wherein the set of top CMD yarns comprises a third number of top CMD yarns in each repeat unit, and wherein the set of bottom CMD yarns comprises a fourth number of bottom CMD yarns in each repeat unit, and wherein the third number is twice as large as the fourth number.
4. The triple layer papermaker's fabric defined in claim 1 , wherein each stitching yarn of each pair interweaves with the bottom MD yarns.
5. The triple layer fabric defined in claim 4 , wherein each of the stitching yarns passes below one bottom MD yarn.
6. The triple layer papermaker's fabric defined in claim 1 , wherein together the top MD yarns, the top CMD yarns, and the stitching yarns form a plain weave pattern on a top surface of the fabric.
7. The triple layer papermaker's fabrics defined in claim 1 , wherein each of the bottom MD yarns passes under a different number of bottom CMD yarns as its two immediate neighboring bottom MD yarns.
8. The triple layer papermaker's fabric defined in claim 1 , wherein each of the bottom MD yarns passes under at least two bottom CMD yarns that one of its immediate neighboring bottom MD yarns passes under.
9. The triple layer papermaker's fabric defined in claim 7 , wherein each of the bottom MD yarns passes under at least two bottom CMD yarns that one of its immediate neighboring bottom MD yarns passes under.
10. The triple layer papermaker's fabric defined in claim 1 , wherein the mesh ratio of a top surface of the fabric is between about 20×30 and 30×50 epcm to ppcm.
11. The triple layer papermaker's fabric defined in claim 1 , wherein each of the stitching yarns of a pair forms the same number of top side CMD knuckles as the other stitching yarn of that pair.
12. The triple layer papermaker's fabric defined in claim 1 , wherein the second number is twice as great as the first number.
13. The triple layer papermaker's fabric defined in claim 1 , wherein the first number is eight, and the second number is sixteen.
14. The triple layer papermaker's fabric defined in claim 3 , wherein the third number is thirty-two, and the fourth number is sixteen.
15. A triple layer papermaker's fabric, comprising:
a set of top machine direction (MD) yarns;
a set of top cross machine direction (CMD) yarns interwoven with the top MD yarns to form a top fabric layer;
a set of bottom MD yarns;
a set of bottom CMD yarns interwoven with the bottom MD yarns to form a bottom fabric layer; and
a set of stitching yarn pairs that interweave with the top MD yarns, wherein at least one of the yarns of each stitching yarn pair interweaves with the bottom MD yarns;
wherein the top MD yarns and the top CMD yarns are interwoven in a series of repeat units and the bottom MD yarns and the bottom CMD yarns are interwoven in a series of corresponding repeat units;
wherein the set of top MD yarns comprises a first number of top MD yarns in each repeat unit, and the set of bottom MD yarns comprises a second number of bottom MD yarns in each repeat unit, and wherein the second number is twice as great as the first number; and
wherein each bottom MD yarn follows a different interweaving pattern than that followed by each of its two immediate neighboring bottom MD yarns.
16. The triple layer papermaker's fabric defined in claim 15 , wherein a stitching yarn pair is positioned between each adjacent pair of top CMD yarns.
17. The triple layer papermaker's fabric defined in claim 15 , wherein the set of top CMD yarns comprises a third number of top CMD yarns in each repeat unit, and wherein the set of bottom CMD yarns comprises a fourth number of bottom CMD yarns in each repeat unit, and wherein the third number is twice as large as the fourth number.
18. The triple layer papermaker's fabric defined in claim 15 , wherein each stitching yarn of each pair interweaves with the bottom MD yarns.
19. The triple layer papermaker's fabric defined in claim 18 , wherein each of the stitching yarns passes below one bottom MD yarn.
20. The triple layer papermaker's fabric defined in claim 15 , wherein together the top MD yarns, the top CMD yarns, and the stitching yarns form a plain weave pattern on a top surface of the fabric.
21. The triple layer papermaker's fabric defined in claim 15 , wherein each of the bottom MD yarns passes under the same number of bottom CMD yarns.
22. The triple layer papermaker's fabrics defined in claim 15 , wherein each of the bottom MD yarns passes under a different number of bottom CMD yarns as its two immediate neighboring bottom MD yarns.
23. The triple layer papermaker's fabric defined in claim 15 , wherein each of the bottom MD yarns passes under at least two bottom CMD yarns that one of its immediate neighboring bottom MD yarns passes under.
24. The triple layer papermaker's fabric defined in claim 22 , wherein each of the bottom MD yarns passes under at least two bottom CMD yarns that one of its immediate neighboring bottom MD yarns passes under.
25. The triple layer papermaker's fabric defined in claim 15 , wherein the mesh ratio of a top surface of the fabric is between about 20×30 and 30×50 epcm to ppcm.
26. The triple layer papermaker's fabric defined in claim 15 , wherein each of the stitching yarns of a pair forms the same number of top side CMD knuckles as the other stitching yarn of that pair.
27. A method of making paper, comprising the steps of:
(a) providing a papermaker's fabric, the papermaker's fabric comprising:
a set of top machine direction (MD) yarns;
a set of top cross machine direction (CMD) yarns interwoven with the top MD yarns to form a top fabric layer;
a set of bottom MD yarns;
a set of bottom CMD yarns interwoven with the bottom MD yarns to form a bottom fabric layer; and
a set of stitching yarn pairs that interweave with the top MD yarns, wherein at least one of the yarns of each stitching yarn pair interweaves with the bottom MD yarns;
wherein the top MD yarns and the top CMD yarns are interwoven in a series of repeat units and the bottom MD yarns and the bottom CMD yarns are interwoven in a series of corresponding repeat units;
wherein the set of top MD yarns comprises a first number of top MD yarns in each repeat unit, and the set of bottom MD yarns comprises a second number of bottom MD yarns in each repeat unit, and wherein the second number is greater than the first number; and
wherein each bottom MD yarn follows a different interweaving pattern than that followed by each of its two immediate neighboring bottom MD yarns;
(b) applying paper stock to the papermaker's fabric; and
(c) removing moisture from the paper stock.
28. A method of making paper, comprising the steps of:
(a) providing a papermaker's fabric, the papermaker's fabric comprising:
a set of top machine direction (MD) yarns;
a set of top cross machine direction (CMD) yarns interwoven with the top MD yarns to form a top fabric layer;
a set of bottom MD yarns;
a set of bottom CMD yarns interwoven with the bottom MD yarns to form a bottom fabric layer; and
a set of stitching yarn pairs that interweave with the top MD yarns, wherein at least one of the yarns of each stitching yarn pair interweaves with the bottom MD yarns;
wherein the top MD yarns and the top CMD yarns are interwoven in a series of repeat units and the bottom MD yarns and the bottom CMD yarns are interwoven in a series of corresponding repeat units;
wherein the set of top MD yarns comprises a first number of top MD yarns in each repeat unit, and the set of bottom MD yarns comprises a second number of bottom MD yarns in each repeat unit, and wherein the second number is twice as great as the first number; and
wherein each bottom MD yarn follows a different interweaving pattern than that followed by each of its two immediate neighboring bottom MD yarns;
(b) applying paper stock to the papermaker's fabric; and
(c) removing moisture from the paper stock.