Patent Application
20250075382
This invention relates generally to tubular protective sleeves for providing protection to elongate members contained therein, and more particularly to knitted tubular protective sleeves and to their method of construction.
Single wall tubular sleeves are known for protecting elongate members against thermal conditions. The sleeves are commonly constructed from heat resistant yarns, such as silica, fiberglass, ceramic, basalt, aramid or carbon, to withstand relatively high temperatures. Although the sleeves are generally effective at providing a thermal barrier, the heat-resistant yarn that forms the outer wall of the sleeves is generally susceptible to damage. Accordingly, if protection against abrasion, impact or crush resistance is needed, an additional sleeve(s) is typically disposed in a separate operation about the single wall sleeve. Although this can prove helpful, it is generally labor intensive, bulky and costly.
In accordance with one aspect of the invention, a tubular sleeve for providing thermal protection about an elongate member, such as a bus bar of an electric vehicle battery pack, contained therein is provided. The tubular sleeve includes a knitted inner wall having a circumferentially continuous outer surface and a circumferentially continuous inner surface. The circumferentially continuous inner surface bounds a cavity that extends lengthwise along a longitudinal central axis between opposite inner ends of the knitted inner wall. The tubular sleeve further includes a knitted outer wall having a circumferentially continuous outer surface and a circumferentially continuous inner surface. The knitted outer wall extends lengthwise about the longitudinal central axis between opposite outer ends and overlies the knitted inner wall. Further, an intermediate yarn extends back and forth between the knitted outer wall and the knitted inner wall to connect the knitted outer wall and the knitted inner wall to one another.
In accordance with another aspect of the invention, the knitted inner wall is knitted entirely with a first yarn forming interlinked inner knitted stitches and the knitted outer wall is knitted entirely with a second yarn forming interlinked outer knitted stitches, the inner knitted stitches not knitted to the outer knitted stitches.
In accordance with another aspect of the invention, the intermediate yarn is the sole connection of the knitted inner wall to the knitted outer wall.
In accordance with another aspect of the invention, the intermediate yarn is knitted with a tuck stitch.
In accordance with another aspect of the invention, the inner knitted stitches and the outer knitted stitches are formed using weft knitted stitches.
In accordance with another aspect of the invention, the weft knitted stitches are jersey stitches.
In accordance with another aspect of the invention, the first yarn and the second yarn are multifilaments.
In accordance with another aspect of the invention, the first yarn and the second yarn can be provide as different types of material to optimized the desired performance attributes of the inner and outer walls.
In accordance with another aspect of the invention, the multifilaments consist of at least one of, fiberglass, ceramic, basalt, silica, slate, slag, aramid and carbon.
In accordance with another aspect of the invention, the intermediate yarn is a monofilament.
In accordance with another aspect of the invention, the monofilament is heat-set to impart a bias on both the knitted inner wall and the knitted outer wall to maintain the knitted inner wall and the knitted outer wall, and the cavity bounded by the inner wall, having a predetermined shape.
In accordance with another aspect of the invention, the opposite inner ends are radially aligned with the opposite outer ends in substantially flush relation.
In accordance with another aspect of the invention, a method of constructing a tubular textile sleeve for providing thermal protection about an elongate member is provided. The method includes knitting an inner wall having a circumferentially continuous outer surface and a circumferentially continuous inner surface, with the circumferentially continuous inner surface bounding a cavity extending lengthwise along a longitudinal central axis between opposite inner ends of the knitted inner wall, on two separate beds of a four-bed weft knitting machine. Further, knitting an outer wall in overlying relation with the inner wall, and knitting the outer wall having a circumferentially continuous outer surface and a circumferentially continuous inner surface, with the knitted outer wall extending lengthwise about the longitudinal central axis between opposite outer ends, on two separate beds, different from the two separate beds used to knit the inner wall, of the four-bed weft knitting machine. Further yet, knitting an intermediate yarn back and forth between the outer wall and the inner wall to connect the outer wall and the inner wall to one another.
In accordance with another aspect of the invention, the method can further include knitting the intermediate yarn using tuck stitches.
In accordance with another aspect of the invention, the method can further include knitting the inner wall and the outer entirely with multifilament yarns.
In accordance with another aspect of the invention, the method can further include providing the multifilament yarns consisting of at least one of, fiberglass, ceramic, basalt, silica, slate, slag, aramid and carbon.
In accordance with another aspect of the invention, the method can further include using monofilament yarns for the intermediate yarn.
In accordance with another aspect of the invention, the method can further include knitting the inner wall and the outer entirely with jersey stitches.
In accordance with another aspect of the invention, the method can further include knitting the intermediate yarn on all four beds of the four-bed knitting machine.
In accordance with another aspect of the invention, the method can further include shaping the inner wall and the outer wall to form the cavity having a desired shape, and then heat-setting the intermediate yarn to impart a bias on the inner wall and the outer wall to maintain the cavity in the desired shape.
These and other aspects, features and advantages of the present invention will become more readily appreciated when considered in connection with the following detailed description of presently preferred embodiments and best mode, appended claims and accompanying drawings, in which:
Referring in more detail to the drawings,
As best shown in
The knitted outer wall 14a is seamless and circumferentially continuous, having an outer surface 26 and an inner surface 28. The knitted outer wall 14a extends lengthwise about the longitudinal central axis 22 between opposite outer ends 30a, 30b, in overlying relation with the knitted inner wall 14b. The outer ends 30a, 30b are knitted being radially aligned with the opposite inner ends 24a, 24b in flush or substantially flush (meaning that to the naked eye, they appear flush, but could be a few millimeters different) relation with one another. The outer wall 14b is knitted entirely with a second yarn Y2 forming interlinked outer knitted stitches 38. The second yarn can be the same type of yarn as the first yarn, or a different type of yarn, as desired for the application. Accordingly, the yarn used to knit the outer wall 14a can have the same resistance to heat or less resistance to heat than the yarn used to knit the inner wall 14b, depending on the application needs. As such, it is contemplated that a yarn more well suited to withstand abrasion and impact from external debris can be used to construct the outer wall 14a, thereby resulting in the sleeve 10 being both able to withstand abrasion and debris from external sources via the outer wall 14a with significant damage thereto, while also being resistance to extreme heat, while providing dielectric protection. Some yarns believed to be suitable for providing increased abrasion resistance to the outer wall 14a include polyester, nylon, polypropylene, polyethylene, acrylic, cotton, rayon, and fire retardant (FR) versions of all the aforementioned materials, as desired for the intended application. In addition to the aforementioned materials, if desired, it is contemplated that the same mineral fiber yarn(s) used to construct the inner wall 14b, or different mineral fiber yarn(s), could be used to construct the outer wall 14a.
During the knitting process, the outer wall 14a is knitted integrally with the inner wall 14b via an intermediate yarn 40 extending back and forth between the knitted loops of the outer wall 14a and the knitted loops of the inner wall 14b via a tuck stitch to connect the knitted outer wall 14a and the knitted inner wall 14b to one another. The intermediate yarn 40, extending through loops of the outer wall 14a and the inner wall 14b is the sole connection of the outer wall 14a to the inner wall 14b, thereby physically coupling and preventing separation of the outer wall 14a from the inner wall 14b. Accordingly, in the absence of the intermediate yarn, the outer wall 14a and the inner wall 14 would be separable from one another. The intermediate yarn 40 can be provided as a monofilament yarn having an increased stiffness relative to the multifilament yarn used for the outer and inner walls 14a, 14b. Having an increased relative stiffness facilitates maintaining the wall 14 having a cylindrical shape. In accordance with another aspect, the intermediate yarn 40 can be provided as a heat-settable yarn, such that upon forming the wall 14 into a desired cylindrical shape, whether a right circular cylinder, rectangular cylinder, or other prismatic-shaped cylinder, the heat-settable yarn can be heat-set to impart of bias on the knitted outer wall 14a and inner wall 14b to maintain the wall 14 having the desired shape and contour along its length, extending uniformly from one end to the opposite end of the wall 14.
The type of knit stitches used to construct the outer and inner walls 14a, 14b can be varied, as desired, for the intended application, but regardless of the type of knit stitch, the stitches are formed via weft knitted stitches. Accordingly, the wall 14 can be knit using any type or combination of knit stitches, e.g. jersey, interlock, rib forming stitches, or otherwise, such that the outer and inner walls 14a, 14b may be knit using a single or multiple knit stitch types, wherein the types of knit stitches used to form the outer and inner walls 14a, 14b can be the same or different from one another. Further, the wall 14 can be constructed having any suitable length and diameter. As will be evident to one possessing ordinary skill in the art, the diameter of the outer wall 14a is controlling, as the inner wall 14b is constrained by the inner surface 28 of the outer wall 14a.
In accordance with another aspect of the disclosure, a method of constructing a tubular sleeve 10 for providing thermal protection about an elongate member 12 is provided. The method includes knitting an inner wall 14b having a circumferentially continuous outer surface 16 and a circumferentially continuous inner surface 18, with the circumferentially continuous inner surface 18 bounding a cavity 20 extending lengthwise along a longitudinal central axis 22 between opposite inner ends 24a, 24b of the knitted inner wall 14b on two separate beds 32b, 32c of a four-bed weft knitting machine 15. Further, knitting an outer wall 14a having a circumferentially continuous outer surface 26 and a circumferentially continuous inner surface 28 in overlying relation with the inner wall 14b, with the knitted outer wall 14a extending lengthwise about the longitudinal central axis 22 between opposite outer ends 30a, 30b, on two separate beds 32a, 32d, different from the two separate beds 32b, 32c used to knit the inner wall 14b, of the four-bed weft knitting machine 15. Further yet, knitting an intermediate yarn 40 back and forth between the outer wall 14a and the inner wall 14b to connect the outer wall 14a and the inner wall 14b to one another.
Many modifications and variations of the present invention are possible in light of the above teachings, as will be readily appreciated by one possessing ordinary skill in the art. It is contemplated that all features of all claims and of all embodiments can be combined with each other, so long as such combinations would not contradict one another. It is, therefore, to be understood that the invention may be practiced otherwise than as specifically described, and that the scope of the invention is defined by any ultimately allowed claims.
