The present invention relates to a protective cover intended to provide abrasion protection, primarily but not exclusively, for lifting slings, ropes and other elongate load-bearing members such as mooring and towing cables and the like. However, the cover may have wider application in the protection of other elongate structures such as telecommunication cables, electrical cables and the like from abrasion, cutting or sawing.

Protective textile covers are already known and are primarily used to protect the fibre ropes that are used extensively in marine applications and in soft lifting slings. In both of these fields, the fibre ropes suffer from the same weaknesses, namely their low resistance to cutting and abrasion because of the nature of their predominantly textile construction. The protective covers used to protect the fibre ropes in these fields comprise seamless sleeves that are usually woven in one piece from man-made fibres _^

However, in many applications it is often a requirement that two or more ropes or slings are used in tandem with one another, for example to provide a single wide and/or heavy load-carrying sling. In these circumstances it is advantageous if each rope or sling element is separately contained in its own sleeve to prevent tangling and to prevent the rope or sling elements abrading one another. To date, conventional covers designed to do this are manufactured by the creation of a seam down the middle of a tubular cover after the ropes or sling elements have been inserted into the cover. The seam is created by stitching or stapling between the ropes or sling elements, by fusing the upper and lower parts of the material of the cover together, or by using a hot melt adhesive. None of these methods is satisfactory for producing a strong seam and there is always the danger that during creation of the seam one or more of the fibres of the ropes or sling elements may be caught up in the seam or otherwise damaged. Also, in some applications, bundles of single, untwisted yarns are used as these provide a greater load-bearing capacity than a twisted rope but the capacity for tangling of the yarns of such bundles is considerable. Hence, the use of separate sleeves to keep each yarn bundle separate from the others is advantageous. One object of the present invention is to provide a protective cover that provides the aforementioned advantages whilst overcoming the aforementioned disadvantages caused during seam production. Another object of the present invention is to provide an improved cover for use with load-bearing members comprising untwisted yarn bundles.

According to the present invention there is provided a protective cover for lifting slings, ropes and other elongate structures used in tandem comprising a multi-ply woven tubular structure openable in use to provide at least two adjacent, woven-in sleeves that are each adapted to accommodate one of the elongate structures and that are separated from one another by a seam formed by at least one serpentine stitcher thread that is woven between the plies of the structure during weaving of the structure.

The serpentine stitcher thread or threads are warp threads that are additional to the weave pattern of the tubular structure and that are incorporated into the weave to form a seam during weaving of the cover. The stitcher thread or threads are woven with a serpentine path in the region of the seam. Preferably, each serpentine stitcher thread weaves an S-shaped path between corresponding picks in adjacent plies of the tubular structure. This means that in the region of the seam the weft yarns of each ply are pulled together to prevent separation of the plies.

Preferably also, the serpentine stitcher thread or threads are warp yarns that are woven with a higher tension than the other warp yarns.

Preferably also, the or each seam formed by the stitcher threads is located at an appropriate position across the width of the woven structure to create sleeves of predetermined diameters. Preferably also, each serpentine stitcher thread interlocks the plies of the structure along the length of the cover and weaves an S-shaped path between picks in the plies forming an upper wall part of each sleeve and corresponding picks in the plies forming a lower wall part of each sleeve.

In some embodiments preferably at least one inner ply of the woven structure forms a dividing wall that splits at least one sleeve into upper and lower sleeves.

In another embodiment preferably the woven structure of the cover also comprises a woven-in outer protective tube in which the tubular structure defining the at least two tubular sleeves is located. Other preferred but non-essential features of the invention are described in the dependent claims.

The present invention will now be described by way of example with reference to the accompanying drawings, in which :-

Figs, l and 2 are schematic transverse cross-sections of first and second embodiments of protective cover in accordance with the present invention; Fig. 3 is a schematic longitudinal section showing the weave structure at a seam location, labelled A in Figs, l, 2, 6, 7 and 8, of a seam in the covers shown in Figs. 1 and 2;

Fig. 4 is an example of a weave pattern diagram for the weave structure shown in Fig. 3; Fig. 5 is a longitudinal section of an upper or lower wall part of a sleeve of a modified protective cover in accordance with the present invention; Fig. 6 is a schematic transverse cross-section of a third embodiment of protective cover in accordance with the present invention;

Fig. 7 is a schematic transverse cross-section of a fourth embodiment of protective cover in accordance with the present invention; and

Fig. 8 is a schematic transverse cross-section of a fifth embodiment of protective cover in accordance with the present invention.

When reading the following description, it should be appreciated that the encircled numerals shown in Fig. 3 relate to the pick and shaft numbers respectively being the "horizontal" and "vertical" lines of the weave pattern diagram shown in Fig. 4 only and are not related to the reference numerals used for parts of the invention that are shown without encirclement in the drawings.

With reference to Figs. 1 and 2, the present invention comprises a protective cover 1, 2 that comprises a multi-ply woven structure that is openable in use to provide at least two adjacent, woven-in sleeves 3 that are separated from one another by one or more seams A formed during the weaving process. In Figs. 1 and 2 structures with two and three sleeves 3 respectively are shown but any required number can be created during weaving. These structures can be opened out to form the sleeves 3 by virtue of their multi-ply weave pattern and are woven from warp yarns 4 and weft yarns forming picks 5, as shown in Fig. 3 wherein the warp yarns 4 are shown by the unbroken lines.

In Fig. 3 is shown a longitudinal section of the protective cover shown in Fig. 1 or in Fig. 2 at one of the seam locations A. The warp 4 is shown as solid lines and the weft 5 is shown in cross-section to a significantly increased scale for ease of interpreting the diagram. In both of the covers 1 and 2 the warp 4 and weft 5 are arranged to form four plies 6a, 6b, 6c, 6d. The first and second plies 6a and 6b are connected by binder yarns 7 (shown as dotted lines) that comprise additional yarns which are crossed between the plies 6a and 6b. Similarly, the third and fourth plies 6c and 6d are connected by binder yarns 8 (also shown as dotted lines) that also comprise additional yarns which are crossed between the plies 6c and 6d. The second and third plies 6b and 6c are unconnected by binder yarns 7, 8 so that there is an interior space between the plies 6b and 6c that allows the structure to be opened up in use whereby each sleeve 3 comprises upper and lower wall parts, ga and 9b respectively, of at least two ply thickness. However, the plies 6b and 6c may be connected along the edges of the structure, for example by selvage edges, and are also connected by one or more stitcher threads 10, 11 (shown by dot-dashed lines) that are woven as special threads between all the plies 6a to 6d of the structure to form seams 12 at one or more locations A (see Figs. 1, 2, 6, 7 and 8) across the width of the structure relative to the weft yarns 5 to create the sleeves 3. It will be appreciated that the spacing of the seams 12 at predetermined positions across the structure creates sleeves 3 of predetermined widths or diameters, which may be the same or different as required. However, away from the seams 12 the structure is woven as shown in Fig. 3 with the omission of the stitcher threads 11, 12.

In contrast, at the seams 12 the stitcher threads 10, 11 interlock the plies 6a to 6d of the structure together along the length of the cover. Each stitcher thread 10 , 11 is woven in a serpentine path which means that each stitcher thread 10, 11 weaves an S-shaped path between corresponding picks in adjacent plies of the tubular structure. In the embodiment shown in Fig. 3 the stitcher threads 10, 11 are woven with an S-shaped path between the wefts yarns 5 in the plies 6a, 6b forming the upper wall part 9a of each sleeve and their corresponding weft yarns 5 in the plies 6c, 6d forming the lower wall part 9b of each sleeve 3. The use of a serpentine weave pattern for the stitcher threads 10, 11 tightly pulls the plies 6a to 6d together longitudinally along the length of the structure and across its depth to define the sleeves 3. Also, the stitcher thread or threads 10, 11 are preferably woven with a higher tension than the other warp yarns 4 to ensure tight seams 12. Although a single serpentine stitcher thread can be used to create each seam, preferably there are at least two serpentine stitcher threads 10, 11 in each seam 12. Each stitcher thread 10, 11 is woven in an S-shaped path between adjacent picks in the plies 6a, 6b forming the upper wall part 9a of each sleeve 3 and the corresponding picks in the plies 6c, 6d forming the lower wall part 9b of the sleeve 3 whereby the stitcher yarns 10, 11 cross each other, as shown at 13 between two adjacent picks 5 in the upper and lower wall parts 9a, 9b respectively. An example of such a weave pattern is shown in the weave diagram of Fig. 4, which corresponds to the repeating weave pattern shown in Fig. 3, both Fig. 3 and Fig, 4 showing one round of weave. This weave pattern is used at the locations A shown in Figs. 1, 2 and 7. In the weave diagram of Fig. 4, in conventional fashion, the "vertical lines" represent the shaft number of the warp insertions comprising the warp 4, the binder yarns 8 and the stitcher threads 10, 11 and the "horizontal" lines represent the picks. The "vertical lines", numbering 1 to 14, correspond to the encircled numbers 1 to 14 down the left-hand side in Fig. 4 and the "horizontal lines", numbering 1 to 16, correspond to the encircled numbers 1 to 16 in the weft yarns 5 in Fig. 4 indicating each of the picks. In the weave diagram at each intersection between the warp and the weft a crossed square indicates that the warp is placed above the weft whereas the squares with circles indicate that the weft is above the warp. In the covers shown in Figs. 6 and 8, the number of plies in the structure at the seam locations A differs from that shown in Fig. 3, as is described below. However, the seams at locations A in these embodiments are also formed from one or more stitcher threads which are woven between the plies in the same way, that is by one or more serpentine stitcher threads that follow an S-shaped path between the picks in the ply or plies forming the upper wall part of each sleeve and corresponding picks in the ply or plies forming the lower wall part of each sleeve. It will be appreciated from the foregoing that the serpentine stitcher thread or threads 10, 11 are warp threads that are additional to the weave pattern of the tubular structure, which weave pattern comprises the warp yarns 4, the weft yarns 5 and the binder yarns 7. The stitcher thread or threads 10, 11 are incorporated into the weave solely to form the seam 12 during weaving and their serpentine path pulls the weft yarns 5 of each ply tightly together to prevent separation of the plies in the region of the seam 12.

The sleeves 3 are adapted so that in use each accommodates one of the ropes, slings or other elongate structures that are to be used in tandem with one another. Unlike conventional covers, the seams 12 of the covers of the present invention are formed during weaving of the cover and not after ropes, sling elements or other elongate structures have been inserted into cover. Hence, in some embodiments it is advantageous for a pull cord 14 to be provided for each sleeve 3, for example as shown in Figs. 1 and 2. Each pull cord 14 runs longitudinally within but is not connected to its sleeve 3 and is incorporated into the sleeve during weaving of the cover 1, 2 by the addition of additional warp yarns that are not interwoven with the weft 5 or stitcher threads 10, 11. The pull cords 14 run along the full length of the sleeves 3 so that, in use, they can each be attached at one end to one of the elongate members to be protected by the cover 1. The pull cords 14 are then withdrawn from the cover 1, 2 thereby pulling the attached elongate members into the sleeves 3.

In the embodiments shown in Figs., 1 and 2 the wall parts 9a, 9b of each sleeve 3 are of 2-ply construction although it is possible for these wall parts 9a, 9b to be of single ply construction, in which case the tubular structure would be woven with only two plies. In a modified arrangement (not shown) the tubular structure may be woven with four plies and opened to provide upper wall parts 9a that are a single ply and lower wall parts 9b that are 3- ply. However, preferably for strength and durability both of the wall parts 9a, 9b are of at least 2-ply construction and in some embodiments may be made of 3-ply construction. In embodiments with wall parts 9a, 9b of two or more plies, each upper and/or lower wall part 9a, 9b may be woven using a binderless weave pattern, as shown in Fig. 5. The stitcher threads are omitted from Fig. 5, which shows only the construction of either an upper or a lower wall part, 9a or 9b respectively, away from a seam 12 so that no stitcher threads are present. A binderless weave is also used to form the sleeves of the embodiment shown in Fig. 8 and similar embodiments where each sleeve 3 is effectively split into two or more additional sleeves, as is described in more detail below.

A third embodiment of cover 15 is shown in Fig. 6. Here, the cover 15 comprises a woven-in outer protective tube 16 in which the tubular structure defining at least two tubular sleeves 3 is located. Such a cover 16 is woven using a 4-ply weave wherein the first and fourth plies form the outer tube 16 and the second and third plies form an inner tube that is provided with a seam 12 at location A formed by stitcher threads as described above. Each of the sleeves 3 has wall parts 9a, 9b of only a single ply. However, it will be appreciated that covers 15 with an outer protective tube 16 may be woven by adding two additional plies to the top and bottom of the weave that forms the cover 1 as shown in Fig. 1 to provide sleeves 3 with wall parts 9a, 9b that are each of 2 ply construction. In all cases the outer tube 16 and the inner tubular structure are connected at a selvage 17 by binder yarns along at least one side but are otherwise unconnected. This enables the outer tube 16 to move around and slide relative to the sleeves 3 of the inner tubular structure. An advantage of the outer tube 16 when the inner cover 15 is used on a lifting sling or similar is that it protects the inner cover 15 from wear and abrasion caused by load being lifted. In another embodiment of cover 18 as shown in Fig. 7, the woven structure comprises an additional seam 19 adjacent one longitudinal edge of the cover 18 that is also formed by serpentine stitcher threads as described above. However, the upper and lower plies of the cover 18 are not joined at the edge of the cover adjacent the seam 19 so that it is provided with upper and lower flaps 20, 21 that run along the length of the cover adjacent one of the sleeves 3. These flaps 20, 21 are useful in some embodiments for wrapping around fixed items. To this end, the flaps 20, 21 may be provided with respective parts of a hook and loop fastener 22 such as Velcro® whereby the flaps 20, 21 may be wrapped around an item and then secured together. Connecting means other than Velcro® may also be used.

In a further more complex embodiment of cover 23 is shown in Fig. 8. The cover 23 is similar to the cover 2 shown in Fig. 2 but each of the three sleeves produced by the seams at locations A is split to provide upper, lower and intermediate sleeves 3a, 3b and 3c respectively. Such a cover 23 is produced by weaving the 4-ply structure in a binderless weave so that the two inner plies can be used as dividing wall parts 24a and 24b between upper and intermediate sleeves 3a, 3c and lower and intermediate sleeves 3b, 3c respectively. Hence nine separate sleeves are formed in a 3 x 3 x 3 pattern. However, it will be appreciated that many variations can be produced using a similar weave principle. In particular, if a 5-ply structure is woven, then a cover with sleeves having 2-ply upper and lower wall parts 9a, 9b and an intermediate single-ply dividing wall can be produced to form sleeves in a 2 x 2 pattern. It will be appreciated that any number of split sleeves can be produced by appropriate location of the seams. Also, covers can be produced wherein some of the sleeves are split into intermediate sleeves and others are not. Covers 23 and similar covers are is advantageous when in use covering some load-bearing members as the closer the latter are arranged the greater the load-bearing strength of the structure.

In all embodiments, the woven-in sleeves 3 may be formed predetermined distances from one and/or both ends of a cover, the ends beyond the edges of the sleeves being tubular. This enables the cover to be used on load-bearing structures, in particular lifting slings that are conjoined and then split into separate elements. The cover is preferably woven from a tough, cut-resistant, high- strength yarn. These are typically made from man-made fibres, for example ultra-high molecular weight polyethylene (UHMwPE) yarns, liquid crystal polymer yarns, thermoset liquid crystalline polyoxazolet yarns, polyethylene terephthalate (PET) polymer yarns, polyamide fibre yarns, polypropelyene (PP) and polyethylene (PE) polyolefm yarns, aramid yarns, carbon fibre yarns and fibreglass yarns. Mixtures or combinations of these yarns or other suitable man-made fibre yarns may also be used. However, dependent on the intended use of the cover, it may be woven from any appropriate yarn or yarns including yarns incorporating metal strands or comprising metal wires. Such a cover can be made in appropriate dimensions as required, with any number of sleeves 3 each of which can be of any desired width and with split sleeves if required. If the cover is to be used in the open air, as will most likely be the case, the outer plies or the outer protective tube may be woven from ultra-high molecular weight polyethylene (UHMwPE) yarns as these are resistant to ultra-violet radiation. Alternatively or in addition, the outer surface of the cover may be covered by a protective coating, as proposed below. Also, in conventional fashion at least some of the warp and/or weft in the inner plies may be coloured differently from the warp and weft in the outer plies. This provides an indicator of wear of the cover, which should be replaced if any of the coloured warp or weft threads become visible from the exterior of the cover.

After weaving, any of the covers as described above may be further treated to enhance its performance, for example to improve its abrasion- resistant properties, increase its cut-resistance and to increase its resistance to ultra-violet radiation. Such treatments may include coating the outer surface of the cover with latex or gel materials and gel-coated yarns may also be included in the weave of the cover for similar purposes.