GB2102730A

GB2102730A - Improvements relating to pin seams

Info

Publication number: GB2102730A
Application number: GB08220859A
Authority: GB
Inventors: Chester J Skubel
Original assignee: Albany International Corp
Current assignee: Albany International Corp
Priority date: 1981-07-31
Filing date: 1982-07-19
Publication date: 1983-02-09
Also published as: IT8248905A0; AU8639182A; FI822662A0; DE3227433A1; NZ201383A; NL8202968A; FR2510621A1; FI822662L; GB2102730B; SE8204525D0; SE8204525L; BE894000A; BR8204416A

Abstract

The two ends of a length of fabric such as a papermaker's dryer belt 10 are joined together by a sewn loop pin seam which comprises two series of loops 20, 20a which are meshed with each other and interconnected by a pin 24 which passes through all the loops. The loops 20, 20a are formed by flat monofilaments 16, 16a interwoven with the ends of the fabric. The use of flat filaments 16, 16a which have a thickness substantially less than that of circular filaments of equal strength and less than that of the filaments forming the fabric, decreases the overall thickness of the pin seam and this makes it much less subject to wear when the belt is in use. <IMAGE>

Description

SPECIFICATION Improvements relating to pin seams This invention relates to pin seams for joining together the ends of a length of fabric, such as a papermaker's dryer belt or forming wire.

The seam comprises a row of loops projecting from each end of the fabric, the loops at the two ends being meshed and fixed together by a pin which passes through all the loops.

A number of seam constructions are known for joining the ends of fabrics such as dryer belts and forming wires. The loops of the seams may be formed integrally with the fabrics or made separately for attachement at a later time. U.S. Patent Nos. 3,436,041, 3,653,097, 4,006,760, 4,026,331, 4,123,022 and 4,186,780 disclose various seam constructions for joining the ends of fabrics. Many are applicable to the forming or pressing sections of papermaking machines.

A pin seam has been defined as a seam including opposing sets of projecting loops which are connected by means of a pin when intermeshed. The loops may be provided by weaving a yarn into a fabric such that loops are formed near the end edges thereof. Such a seam is known as a sewn loop seam. Since the yarn extends both above and below the surfaces of the fabric which is to be joined and thus made endless, there tends to be extensive wear in the area of the seam. The loop yarns eventually wear out causing failure.

The thickness of the seam portion is a major factor in contributing to this problem.

The present invention is directed to an improved sewn loop pin seam which has superior wearability in comparison with those presently known.

According to this invention, a substrate fabric is provided with a series of projecting loops forming one half of a sewn loop pin seam, said half pin seam comprising a substantially flat monofilament yarn interwoven with said substrate fabric, said monofilament yarn forming said series of loops projecting from an edge of said substrate fabric and being spaced apart along said edge so that when meshed with a similar series of loops, a pin can be inserted through all said loops to form a pin seam.

The monofilament yarn has an opposing pair of large flat surfaces and a pair of smaller opposing edges. The flat surfaces together with the upper and lower planar surfaces of the substrate fabric define a relatively flat profile and a smoother, more uniform seam than previous sewn loop seams. A substantial reduction in caliper is obtained as compared with seams manufactured with monofilament yarns having a round cross section. Higher caliper seams tend to wear out more rapidly.

Seams made in accordance with the invention minimize the loss of fibres in the papermaking process and prevent marking of the product being conveyed.

An example of a fabric having its ends joined by a pin seam comprising two half pin seams in accordance with the invention is illustrated in the accompanying drawings in which: Figure 1 is a perspective view of a portion of the endless fabric; Figure 2 is a plan view to a larger scale of a portion of the sewn loop seam of the fabric shown in Fig. 1; Figure 3 is a sectional view as seen in the direction of the arrows on the line 3-3 of Fig.

2.

A belt 10 composed of interwoven monofilament warp 1 2 and weft 1 4 yarns is shown in the figures. The yarns are made from a polymeric material and are interwoven in a desired pattern. The illustrated pattern is similar to that shown in U.S. Patent No. 3,436,041 wherein each weft yarn passes alternatively above and then below each succeeding warp yarn. Each yarn has a round cross section, but other cross-sectional configurations may be employed.

A first polymeric monofilament yarn 1 6 is woven into one edge portion of the belt 1 0.

The yarn has a rectangular cross section and is woven such that the opposing large substantially flat surfaces 1 8 thereof form part of the upper and lower surfaces of the resulting seam.

The opposing ends of the flat yarn 1 6 are secured to the belt in any suitable manner. In the structure disclosed herein, one end of the flat yarn is wrapped around the first and second warp yarns defining one edge portion belt and secured thereto by a thermoplastic sealing material 1 7. The opposite end of the flat yarn 1 6 may be secured to the belt 10 in a similar manner.

Each of the loops 20 of the seam are substantially the same size. Adjacent turns of the flat yarn pass, respectively, between the third and fourth weft yarns 14c, 1 4d and the fourth and fifth weft yarns 14d, 14e. The turns are held in place by adjacent warp yarns. A series of loops 22 formed by the flat yarn 1 6 opposite loops 20 engage the weft yarns of the belt in a desired sequence. In the seam shown in the drawings, adjacent loops 22 engage the seventh, eighth, ninth, and eighth weft yarns, respectively. The sequence is repeated for the width of the belt 10.

The opposite edge portion of the belt is also provided with a plurality of loops formed by interweaving a flat polymeric monofilament yarn 16a. It is woven in the same manner to the belt as yarn 1 6. Similar structural features as described with respect to this edge portion are designated by numerals 16-22a.

The opposing edges of the belt are joined by intermeshing loops 20, 20a and inserting a pin 24 therethrough. The resulting seam is 25% smaller in thickness than a similarly manufactured seam having round cross sectional yarns forming the loops. Flat monofilament yarns are of equal tensile strength to round yarns and are better able to resist distortion when the belt is used in the papermaking process. The relatively flat profile of the belt including the seam results in superior guiding of the belt within a papermaking machine. In addition, the flat profile will close up the seam area to minimize loss of product being conveyed or filtered.

The above advantages are obtained by weaving the flat yarns 1 6, 1 6a such that opposing large flat surfaces 18, 1 8a thereof form part of the upper and lower surfaces of the seam. The large flat surfaces accordingly contact a number of the weft yarns of the belt as well as the pin 24.

It will be appreciated that the invention may be used in conjunction with belts of various constructions and materials. The flat monofilament yarns can be interwoven with the belt in a number of different weave patterns. A number of separate flat monofilament yarns can be used for forming loops along the width of the belt.

Claims

1. A substrate fabric provided with a series of projecting loops forming one half of a sewn loop pin seam, said half pin seam comprising a substantially flat monofilament yarn interwoven with said substrate fabric, said monofilament yarn forming said series of loops projecting from an edge of said substrate fabric and being spaced apart along said edge so that when meshed with a similar series of loops, a pin can be inserted through all said loops to form a pin seam.

2. A fabric according to Claim 1, wherein said flat monofilament yarn includes a pair of opposing relatively large flat surfaces interconnected by relatively small edge portions, said large flat surfaces and the surfaces of said substrate fabric forming upper and lower surfaces of said seam half, and the inner and outer portions of said loops being defined by said opposing large flat surfaces.

3. A fabric according to Claim 1 or Claim 2, wherein both said substrate fabric and said flat monofilament yarn are of polymeric material.

4. A fabric according to Claim 3, wherein said substrate fabric includes weft yarns passing alternatively above and below successive warp yarns.

5. A fabric according to any one of the preceding Claims, in which two similar series of the loops project from opposing end edges of the fabric, the two series of loops are meshed with each other and a pin extends through all the meshed loops to form a pin seam joining the two ends of the fabric together.

6. A sewn loop pin seam comprising portions of first and second portions of substrate fabric; first and second substantially flat mo nofila ment yarns interwoven, respectively, with said first and second portions of substrate fabric, said monofilament yarns forming a first series and a second series of loops projecting, respectively, from respective edges of said first and second portions of substrate fabric, said first series of loops meshing with said second series of loops and a pin extending through said meshed loops thereby joining together said first and second portions of substrate fabric.

7. A seam according to Claim 6, wherein said first and second portions of substrate fabric are opposing edge portions of a belt.

8. A seam according to Claim 6 or Claim 7, wherein said first and second flat monofilament yarns each include a pair of opposing relatively large flat surfaces interconnected by relatively small edge portions, said large flat surfaces and the surfaces of said first and second portions of the substrate fabric forming upper and lower surfaces of said seam, and the inner and outer portions of said series of loops being defined by said large flat surfaces.

9. A seam according to any one of Claims 6 to 8, wherein the portions of the substrate fabric and the flat monofilament yarns are of polymeric material.

1 0. A seam according to any one of Claims 6 to 9, in which the flat monofilament yarns are of rectangular cross section.

11. A fabric according to Claim 1, substantially as described with reference to the accompanying drawings.

1 2. A seam according to Claim 6, substantially as described with reference to the accompanying drawings.