Fabric (woven – knitted – or nonwoven textile or cloth – etc.) – Woven fabric – Woven fabric is characterized by a particular or...
Reexamination Certificate
2002-06-07
2004-09-07
Morris, Terrel (Department: 1771)
Fabric (woven, knitted, or nonwoven textile or cloth, etc.)
Woven fabric
Woven fabric is characterized by a particular or...
C442S185000, C442S187000, C442S208000, C442S269000, C442S213000, C442S229000, C428S137000, C428S193000, C428S195100, C139S136000
Reexamination Certificate
active
06787491
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a woven composite fabric, comprising metal elements. Further, the present invention relates to the use of such woven fabric to provide flexible reinforced tubes and/or hoses.
BACKGROUND OF THE INVENTION
Flexible reinforced tubes and hoses are widely known in the art.
A method to produce such reinforced tubes and hoses, comprises the steps of winding reinforcing material round a polymer tube or hose or round a mandrel. E.g. U.S. Pat. No. 3,930,091 shows such method to provide a reinforced tube, winding glasfibers round a mandrel.
When metal elements, being metal wires, bundles of metal wires, metal cords or metal strands are to be used to reinforce a tube or hose, a polymer strip, comprising metal elements running essentially in the longitudinal direction of the strip may be used. Such strips are wound round a polymer tube or on a mandrel. Afterwards, after providing the reinforcing layers, the polymer is to be heated to ensure the adhesion of the polymer layers to each other and eventually to the polymer tube supporting the reinforcing layers.
The advantage of the use of such strips is that only one or a few strips are to be controlled during production of the reinforced tube or hose, rather than controlling individually a large set of metal elements during production.
The present invention relates to disadvantages, which may be met using such polymer strips, comprising metal elements in longitudinal direction. These disadvantages are mainly that no polymer material can make contact with a metal element of an adjacent layer, when two (or more) layers of such strips are wound on top of each other. Further, due to the necessary thickness of the polymer material surrounding the metal elements, a minimum thickness of the reinforcing layer is provided, which for some applications still is too thick. Too much than necessary polymer material may be present between different layers of metal elements.
SUMMARY OF THE INVENTION
As subject of the present invention, a woven composite fabric is provided, comprising metal elements and polymer elements. These polymer elements are, according to the present invention, polymer tapes.
In the scope of the present invention, metal element is to be understood as a metal wire, a bundle of metal wires, a metal strand or a metal cord.
In the scope of the present invention, polymer tape is to be understood as a small tape of polymer sheet. Such polymer tapes have a substantially rectangular cross-section. The width of such tape is preferably less than 10 mm, e.g. less than 5 mm, e.g. 3 mm. The thickness of such tape is preferably less than 100 &mgr;m, e.g. less than 150 &mgr;m, preferably less than 100 &mgr;m, most preferably less than 30 &mgr;m such as 15 &mgr;m. It is clear that the finer the metal element, the thinner the preferred polymer tapes.
Different weaving structures and different weaving densities may be used to provide several alternative woven composite fabrics as subject of the invention. Weaving structures such as plain woven structures, reinforced plain woven structures (with double or multiple warps and/or wefts), twill woven structures, reinforced twill woven structures (with double or multiple warps and/or wefts), satin woven structures, reinforced satin woven structures (with double or multiple warps and/or wefts) may be used.
A weaving density of a woven composite fabric as subject of the invention may be very high. Especially when metal elements are present in only one direction of the woven composite fabric, both polymer tapes and/or metal elements may be present side-by-side in the woven composite fabric. This mainly because of the high flexibility of the polymer tapes. Further, due to the high flexibility of the polymer tapes, the metal elements may run substantially straight in a woven composite fabric as subject of the invention, in case the metal elements are present in only one direction of the fabric. In the opposite direction, in which only polymer tapes are present, these tapes will be bent around the circumference of the metal elements. Since the metal elements are substantially straight, its inweaving factor may be equal to 1.
The inweaving factor is to be understood as the ratio of the length of the element, compared to the length of the fabric, in which the element is present, measured in the direction in which the element runs through the fabric.
In a woven composite fabric as subject of the invention, in which the metal elements are present in only one direction, the polymer tapes in the opposite direction of the fabric will take all inweaving.
Polymer tapes may be present in both directions of the woven fabric (being warp direction and weft direction). However, preferably, polymer tapes are only present in weft direction.
Preferably, the metal elements are only present in either warp or weft direction. Preferably, metal elements are only present in warp direction.
Different weaving processes may be used to provide a woven composite fabric as subject of the invention. A woven composite fabric may be woven on a tape loom, providing strips or bands up to approximately 20 cm width. Alternatively, a woven composite fabric may be woven on a broad loom, as known in the art. Afterwards, such broad woven composite material may be slit in appropriate widths, e.g. 50 cm. When metal elements are only present in warp direction, such fabric as subject of the invention may e.g. be slit by warm cutting of the weft elements, being polymer tapes, so preventing selvedges to unravel.
A woven composite fabric as subject of the invention with metal elements only in warp or weft direction has several advantages. The metal elements run substantially straight in the fabric, since the relatively low thickness of the polymer tapes gives these polymer tapes a high flexibility. This results in an inweaving factor of 1 from the metal elements, whereas all inweaving is done by the polymer tapes. Further, the density of metal elements may be extremely high, since the distance between the circumference two adjacent metal elements can be kept substantially equal to the thickness of the polymer tape. The thickness of a woven composite fabric as subject of the invention with metal elements only in warp or weft direction substantially equals to the thickness of the metal element. If relatively simple weaving structures are used, e.g. plain woven structures, reinforced plain woven structures (with double or multiple warps and/or wefts), twill woven structures, reinforced twill woven structures (with double or multiple warps and/or wefts), satin woven structures, reinforced satin woven structures (with double or multiple warps and/or wefts), the metal elements will always be partially present at both sides of the woven composite fabric, although this may be influenced by the used woven structure.
For certain applications however, it may be preferred to have more polymer material at one side of the woven composite fabric. This may be obtained by weaving a metal element and a polymer tape simultaneously into the woven composite fabric. They behave so to say as twins, while the metal element engages the polymer tape over its whole length at the same long side of the polymer tape. The metal element lies ‘on top of’ the polymer tape. The polymer tape is oriented towards the side of the woven composite fabric, where more polymer material is required.
In other applications, the use of only metal elements and polymer tapes may not provide enough polymer material to the woven composite fabric. In order to obtain a woven composite fabric comprising enough polymer material, some of the polymer tapes and/or metal elements may be replaced by polymer filaments or polymer yarns. Another alternative to provide more polymer material to the fabric is to coat the metal element with a polymer layer, e.g. by extrusion.
Alternatively, a woven composite fabric as subject of the invention may further comprise other reinforcing elements, such as glassfiber yarn or filaments or carbon fiber yarns or filaments.
The eventua
Foley & Lardner LLP
Morris Terrel
N.V. Bekaert S.A.
Salvatore Lynda
LandOfFree
Woven composite fabric does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Woven composite fabric, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Woven composite fabric will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3226626