Wrappable end fray resistant protective textile sleeve and method of construction thereof

A wrappable textile sleeve and method of construction includes an elongate wall having warp yarns extending generally parallel to a longitudinal central axis of the sleeve and fill yarns extending circumferentially about the sleeve. The warp yarns and the fill yarns are woven in an overlying and underlying weave pattern with one another. The warp yarns are arranged in discrete groups alternating about a circumference of the wall with adjacent groups having a different number of the warp yarns. As such, the wall is provided with groups of increased numbers of warp yarns that provide the sleeve with enhanced rigidity and abrasion resistance, while also being provided with groups of decreased numbers of warp yarns that provide the sleeve with enhanced flexibility along the longitudinal central axis.

BACKGROUND OF THE INVENTION

1. Technical Field

This invention relates generally to protective sleeves for elongate members, and more particularly to woven textile sleeves.

2. Related Art

Elongate members, such as wires or wire harnesses, are commonly protected against abrasion and contamination by wrappable textile sleeves. It is known to construct wrappable textile sleeves from woven yarns. In order to form the desired sleeve length, and to avoid fraying the ends of the sleeve, it is known to use lasers, ultrasonic cutting devices, and the like, which melt the material of the sleeve wall during the cutting process, thereby reducing the likelihood of causing the material of the sleeve wall to fray. In addition, it is known to apply a chemical coating agent to the sleeve wall prior to cutting the sleeve wall to reduce the likelihood of fraying the material of the sleeve wall during the cutting process. Although the aforementioned mechanisms can be effective in reducing the likelihood of fraying the material of the sleeve wall, they require specialized cutting devices or processes, and thus, they come at an added cost.

SUMMARY OF THE INVENTION

A wrappable, end fray resistant textile sleeve for protecting elongate members is provided. The sleeve includes an elongate wall having warp yarns extending generally parallel to a longitudinal central axis of the sleeve and fill yarns extending circumferentially about the sleeve. The warp yarns and the fill yarns are woven in an overlying and underlying weave pattern with one another. The warp yarns are arranged in discrete groups alternating about a circumference of the wall with adjacent groups having a different number of the warp yarns. As such, the wall is provided with groups of increased numbers of warp yarns that provide the sleeve with enhanced rigidity and abrasion resistance, while also being provided with groups of decreased numbers of warp yarns that provide the sleeve with enhanced flexibility along the longitudinal central axis.

In accordance with another aspect of the invention, the overlying and underlying weave pattern is formed as one of a plain, rib, basket or twill weave pattern.

In accordance with another aspect of the invention, the overlying and underlying weave pattern is formed as a plain weave pattern. As such, static friction between each of the warp and weft yarns better retains their intended locations within the wall while being cut and during use.

In accordance with another aspect of the invention, each of the warp yarns in each of the discrete groups is woven in the plain weave pattern with the fill yarns, thereby further enhancing the warp and fill yarns being maintained in their intended locations while being cut and during use.

In accordance with another aspect of the invention, the different numbers of the warp yarns in the adjacent groups are X and Y, wherein X is greater than Y.

In accordance with another aspect of the invention, the warp yarns are monofilaments heat-set in a wavy, curly, sinusoidal configuration about the fill yarns. As such, the warp yarns act to grip and hold the fill yarns, thereby facilitating the warp and fill yarns being maintained in their intended locations while being cut and during use.

In accordance with another aspect of the invention, the fill yarns are multifilaments. As such, the wall is provided with enhance protection coverage and the full multifilaments act to grip the warp monofilaments, thereby preventing relative movement between the warp and fill yarns while being cut and during use.

In accordance with another aspect of the invention, the multifilaments have an air texturized finish.

In accordance with another aspect of the invention, the wall has opposite edges extending along the central longitudinal axis wherein the opposite edges are configured for overlapping relation with one another.

In accordance with another aspect of the invention, a method of constructing a wrappable, end fray resistant textile sleeve for protecting elongate members is provided. The method includes forming an elongate wall by weaving warp yarns and fill yarns with one another in an overlying and underlying weave pattern. The method further weaving the warp yarns in discrete groups alternating about a circumference of the wall with adjacent groups having a different number of said warp yarns.

In accordance with another aspect of the invention, the method further includes forming the overlying and underlying weave pattern as one of a plain, rib, basket or twill weave pattern.

In accordance with another aspect of the invention, the method further includes weaving each of the warp yarns in each of the discrete groups with the fill yarns in the plain weave pattern.

In accordance with another aspect of the invention, the method further includes arranging the different number of warp yarns in the adjacent groups having X and Y numbers of respective warp yarns, wherein X is greater than Y.

In accordance with another aspect of the invention, the method includes configuring X to equal 4 and configuring Y to equal 1.

In accordance with another aspect of the invention, the method includes providing the warp yarns as monofilaments and heat-setting the warp yarns to take on a sinusoidal shape.

In accordance with another aspect of the invention, the method includes heat-setting the warp yarns in a calendaring process after weaving the wall.

In accordance with another aspect of the invention, the method includes providing the fill yarns as multifilaments.

In accordance with another aspect of the invention, the method includes providing the fill yarns having an air texturized finish.

In accordance with another aspect of the invention, the method includes weaving the wall as a flat fabric.

DETAILED DESCRIPTION OF PRESENTLY PREFERRED EMBODIMENTS

Referring in more detail to the drawings,FIG. 1illustrates a wrappable, end fray resistant textile sleeve10constructed in accordance with one presently preferred embodiment of the invention. The sleeve10is particularly useful for protecting an elongate member12disposed therein, such as a wire harness, for example. The sleeve10has an elongate wall14having warp yarns16extending generally parallel to a longitudinal central axis17of the sleeve10and fill yarns18extending transversely to the warp yarns16and circumferentially about the wall14. The warp yarns16and fill yarns18are woven with one another in an overlying and underlying weave pattern, such that they undulate over and under one another, such as in a plain, rib, basket or twill weave pattern, for example. In accordance with the invention, the warp yarns16are arranged in discrete groups A, B that alternate with one another about a circumference of the wall14, wherein the groups A, B have a different number of the warp yarns16from one another, shown as group A having an increased number of warp yarns16in comparison to group B. Accordingly, the adjacent groups A, B have different warp yarn densities, although the groups A, B can span the same or substantially the same circumferentially extending width. The relatively increased density group A warp yarns16provide the sleeve10with an overall tightly woven structure. This is because a relatively high number of warp yarns16are contained within close, abutting or substantially abutting relation with one another. As a result of the relatively high density of warp yarns16in groups A, the end fray resistance of the wall14is enhanced when it is cut, such as in a cold-cutting process. Further, the relatively increased density groups A of warp yarns16provide the wall14with enhanced rigidity and abrasion resistance. These results provided by the increased density warp groups A result from the tightly interlocked warp yarns16within the groups A. Meanwhile, the relatively decreased density groups B of warp yarns16provide the sleeve10with enhanced flexibility. This enhanced flexibility is facilitated by gaps provided between the relatively low density groups B and the adjacent increased density groups A.

The sleeve wall14is initially woven as a flat sheet of material19that is further processed after weaving in a heating operation while flat, such as via a calendaring process (FIG. 4). Upon being heated and then cooled, the flat material19is then further processed in a cutting operation, such as via cold-cut operation, though a hot-cut or laser-cut operation can be used, for example, while flat to provide the desired length L of the finished sleeve10, with each of the “as cut” ends forming opposite ends24,26of the sleeve10. The wall14is initially woven having a predetermined width extending between opposite parallel or substantially parallel edges20,22, wherein the edges20,22extend generally parallel to the central longitudinal axis17between the opposite ends24,26. Upon being cut to length L, preferably via cold-cutting for low cost reasons, the opposite edges20,22are configured to be wrapped about the axis17into overlapping relation with one another to form a circumferentially enclosed central cavity28for receipt of the elongate members12.

The warp yarns16are provided mostly or entirely as monofilaments of a heat-formable material, such as poly(ethylene) terephthalate (PET) or poly(phenylene) sulfide (PPS), by way of example and without limitation, and the fill yarns18are provided mostly or entirely as relatively soft yet bulky multifilaments (such as having an air texturized finish, for example). The soft and bulky properties of the fill yarns18provide an increased amount friction against the warp yarns16, thereby acting to stabilize and maintain the warp and fill yarns16,18in their respective “as woven” locations. The warp yarns16are woven in their respectively varying tight and loose density groups A, B by varying the number of warp yarns16in adjacent dents (space between two wires in the loom through which the warp yarns16are drawn). For example, as shown in the resulting woven fabric ofFIG. 2, one dent can receive a single warp yarn16, thereby forming groups B, while an adjacent dent can receive four warp yarns16, thereby forming groups A, with this pattern being repeated in alternating fashion across each of the dents of the loom. With the dents being of equal width, and the number of warp yarns being different within the adjacent dents, the density of warp yarns within adjacent dents is different, as discussed above with regard to the different groups A, B. Of course, this is just an example of the number of warp yarns16can be provided in the adjacent dents, wherein the number of warp yarns per dent can be other than 4 for groups A and 1 for groups B. What is important is that the number X of warp yarns16in groups A is greater than the number Y of warp yarns16in groups B, such that X is greater than Y (FIG. 2A).

Upon weaving the sheet of fabric, the fabric is heat processed while flat (heated and then cooled) to soften and shrink the warp yarns16lengthwise, thereby causing the warp yarns16to take on and retain a high level of crimp that takes a permanent set sinusoidal shape (FIG. 3). As such, the weave, such as a plain weave, of the resulting heat processed fabric is tightened, wherein the heat processed warp yarns16act to hold the weave structure tightly, which in turn facilitates preventing the fill yarns18from fraying (unraveling) during the cutting operation and while the sleeve10is in use. The same mechanism can prevent the warp yarns16from fraying (unraveling) during and after being cold cut along the axial length direction17of the fabric. The heating process can be performed in a calendaring process, wherein the woven flat fabric19is fed from a feed roll30about a surface of a heated roll32, cooled and then stored on a take-up roll34. Of course, the heating process can be a continuous, in-line process with the weaving process. Then, after heat forming the warp yarn16via the calendaring process, the fabric is cut to individual, desired length segments L, such as in a cold cut process, thereby not requiring specialized cutting devices, such as lasers, ultrasonic cutting devices, and the like, or processes, such as use of bonding agents or other chemicals, though they can be used if desired. Then, the “as cut” segments can be wrapped about the elongate members12to provide protection thereto. Of course, any suitable fastening mechanism can be used to retain the edges20,22in their overlapped relation.

Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims and any ultimately allowed claims, the invention may be practiced other than as specifically described and shown.