Abstract:
A textile sleeve for routing and protecting elongate members and method of construction thereof is provided. The textile sleeve has an elongate textile wall constructed from interlaced yarn. An emulsion of acrylic binder and water-based silicon resin is applied to coat the interlaced yarn, with the acrylic binder providing resistance to end fray of the textile sleeve at temperatures below 150° C., and the silicone resin providing resistance to end fray between about 150-500° C.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application Ser. No. 61/249,326, filed Oct. 7, 2009, which is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Technical Field 
         [0003]    This invention relates generally to tubular sleeves for protecting elongate members, and more particularly to flexible textile sleeves. 
         [0004]    2. Related Art 
         [0005]    It is known to wrap wires and wire harnesses in protective textile sleeves to provide protection to the wires against abrasion, fluid and thermal effects. The textile sleeves are typically first woven, braided, or knit, and then subsequent to being formed, the textile material is cold cut to a desired length, whether in manufacture or in the field. Unfortunately, upon cold cutting the textile sleeve material to the desired length, the yarn or yarns used to construct the sleeve typically fray at the cut ends. Thus, the cut ends become unsightly, and further, tend to be a source of degradation, such as by unraveling. 
         [0006]    In an effort to avoid the aforementioned unsightly, problematic cold cut phenomenon, it is known to coat the textile sleeves with a silicone rubber prior to the cutting operation, which allows the sleeve to remain flexible and to be cut with minimal end fray. However, the silicone rubber coating prevents the sleeve from being used in relatively high temperature applications, such as above 150 degrees Celsius (° C.). Thus, there remains a need for a textile sleeve that can be cold cut to length without concern of end fray, with the sleeve being useful at temperatures above 150° C. 
       SUMMARY OF THE INVENTION 
       [0007]    One aspect of the invention provides a textile sleeve for routing and protecting elongate members. The textile sleeve has an elongate textile wall constructed from interlaced yarn. An acrylic binder and water-based silicon resin coating is applied to the interlaced yam, with the acrylic binder providing resistance to end fray of the textile sleeve at temperatures below 150° C., and the silicone resin providing resistance to end fray between about 150-500° C. 
         [0008]    In accordance with another aspect of the invention, a method of constructing a flexible textile sleeve is provided. The method includes interlacing one or more heat-formable yams to form a textile fabric. The method further includes applying an emulsion of water-based silicon resin and acrylic binder to the textile fabric. Then, the method includes heating the coated emulsion at a temperature sufficient to drive off the water from the emulsion without curing the silicon resin. Further, the method includes heat forming the heat-formable yarns at a temperature that is sufficient to form a wall of the sleeve as a self-wrapping tubular wall curling about a longitudinal axis of the sleeve, wherein the temperature is insufficient to cause the silicon resin to cure. 
         [0009]    Accordingly, the invention provides a textile sleeve that remains flexible while applying the textile sleeve about elongate members to be protected. Further, the textile sleeve can be cold cut without causing yams of the textile sleeve to fray. Further yet, the sleeve can withstand temperatures above 150° C. without affecting the protective integrity of the sleeve. In addition, the acrylic binder can be driven off and the silicon resin can be cured at temperatures above about 200° C., with the presence cured silicon resin maintaining protective properties to the sleeve. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    These and other aspects, features and advantages will be readily apparent to those skilled in the art in view of the following detailed description of presently preferred embodiments and best mode, appended claims, and accompanying drawings, in which: 
           [0011]      FIG. 1  is a schematic perspective partial view of a flexible, self-wrapping textile sleeve constructed in accordance with one aspect of the invention shown carrying and protecting elongate members therein; and 
           [0012]      FIG. 2  is an exemplary series of steps used to construct a textile sleeve in accordance with one aspect of the invention. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0013]    Referring in more detail to the drawings,  FIG. 1  illustrates a schematic view of self-wrapping textile sleeve, referred to hereafter as sleeve  10 , constructed in accordance with one aspect of the invention. The sleeve  10  has a elongate wall  12 , such as self-wrapping, for routing and protecting elongate members, such as wires or a wire harness  14 , for example. The elongate wall  12  is constructed from at least one or more yarns  16 , wherein the yam or yams are interlaced to form the wall  12 . At least some of the yarns  16  in the self-wrapping embodiment are provided as heat-settable yams, wherein the heat-settable yarns are heat-set subsequent to being interlaced to bias the wall  12  into a self-wrapping tubular configuration. Accordingly, the wall  12  is self-curled about a central longitudinal axis  18  to provide an enclosed or substantially enclosed tubular inner cavity  20  when the wall  12  is in its relaxed state without an external force acting to uncurl the wall  12  from its self-curled configuration. The cavity  20  is readily accessible along the longitudinal axis  18  of the sleeve  10  so that the elongate members  14  can be readily disposed radially into the cavity  20 , and conversely, removed radially outwardly from the cavity  20 , such as during service. To allow the wall  12  to be cold cut to length without concern of end fray of the yarns  16 , the interlaced yarns  16  have a coating  22  of an emulsion applied thereto, with the emulsion including or consisting of an acrylic binder and water-based silicon resin. The finished coating  22  allows the sleeve  10  to remain flexible up to about 200-250° C., and allows the sleeve  10  to withstand an operating environment temperature up to about 500° C. without degrading. Accordingly, the sleeve  10  is useful in a wide variety of extreme temperature applications to protect the elongate members  14  therein, while at the same time being economical in manufacture and light weight relative to other high temperature, non-textile tubing, such as metal or plastic tubing. 
         [0014]    The wall  12  can be constructed having any suitable size, including length, diameter and wall thickness. The wall  12  has opposite sides  24 ,  26  that extend parallel to the axis  18 . The sides  24 ,  26  terminate at opposite ends  28 ,  29  that are cold cut to a desired length, such as during manufacture or in the field of application. When the wall  12  is in its self-wrapped tubular configuration, generally free from any externally applied forces, the sides  24 ,  26  preferably overlap one another at least slightly to fully enclose the cavity  20  circumferentially. Accordingly, the wall  12  of the sleeve  10  extends circumferentially about the wires  14  to provide full circumferential protection to the wires  14  contained in the cavity  20 . The longitudinally extending sides  24 ,  26  of the sleeve  10  are readily extendable away from one another under an externally applied force to at least partially open and expose the cavity  20 . As such, the wires  14  can be readily disposed radially into the cavity  20  during assembly or removed radially from the cavity  20  during service. Upon releasing the externally applied force from the sides  24 ,  26 , the sides  24 ,  26  return automatically to their relaxed or substantially relaxed, overlapping self-wrapped position under the bias imparted from being heat-set. 
         [0015]    The wall  12  can be constructed from multifilament and/or monofilament yarns  16 , with at least one or more of the yarns  16  in the self-wrapping embodiment being heat-settable. For example, one or more of the yarns  16  can be provided as a heat-settable polymeric material, such as polyphenylene sulfide (PPS), for example, which can be heat-set at a temperature between about 200-225° C. The yarns  16  forming the wall  12  can be interlaced using a variety of interlacing processes, such as weaving, knitting, or braiding, as desired, shown schematically in  FIG. 1  as being woven. 
         [0016]    Upon forming the textile wall  12  with the interlaced yarns  16 , whether using a braiding, knitting or weaving process, the emulsion is applied the yarns  16 , whereupon the coating  22  is formed on the wall  12  and/or impregnated in the yarns  16 . The coating  22  is initially applied on the yarns  16  as an emulsion liquid coating, such as by a spraying, brushing, dipping or roll coating process, for example. The coating  22  is provided as an emulsion of an acrylic binder, such as a carboxylated elastomeric emulsion having a content of about 15-18% by wt., for example, and a water-based silicon resin, such as a methyl phenyl polysiloxane emulsion of about 15-18% by wt, for example. Upon applying the emulsion to the yarns  16 , the water in the emulsion is driven off, such as by application of heat, for example. The heat applied is sufficient to cause the water to be driven off and to provide the wall  12  with a substantially dry feel, however, the silicon resin remains uncured, as the heat is not sufficient to cause the silicon resin to cure. Accordingly, the wall  12  remains freely flexible in an uncured state. 
         [0017]    Then, the wall  12  is wrapped into a tubular configuration, preferably with the opposite sides  24 ,  26  being overlapped relative to one another, and a sufficient heat, such as a temperature between about 200-225° C., is applied to the wall  12  to cause at least some of the heat-settable yarns  16  to be heat-shaped to cause the wall  12  to remain in the wrapped configuration. Accordingly, the wall  12  takes on its self-wrapping tubular form, though the heat applied does not cause the silicone resin to cure. As such, the wall  12  remains freely flexible and uncured so that it can be readily routed about sharp bends and corners in use. Further, with the coating  22  remaining uncured, and the wall  12  remaining flexible, the opposite sides  24 ,  26  can be readily separated via an externally applied force to allow the elongate members to be serviced, as necessary. 
         [0018]    Then, upon forming the wall  16  in the desired configuration, the desired length is established by cold cutting at least one of the ends  28  without the yarns  16  becoming frayed. The lack of fraying is directly attributable to the coating  22  of acrylic binder and silicon resin. 
         [0019]    In use, the sleeve  10  can withstand temperatures to between about 150-200° C. before the acrylic binder in the coating  22  is driven off, however, the silicon resin in the coating  22  remains on the sleeve wall  12 , and may even cure at more elevated temperatures. If the silicon resin cures, the sleeve  10  remains operable to protect the elongate members therein up to temperatures of about 500° C., though it loses its flexibility if the silicon becomes cured. Accordingly, the sleeve  10  is useful over a wide range of temperatures to protect the elongate members  14  therein without having adverse affects on the elongate members  14  or surrounding surfaces, such as can be the case with sleeves having rubber-based coatings that melt. 
         [0020]    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, the invention may be practiced otherwise than as specifically described.