FIELD OF THE INVENTION
The invention concerns a tool for aligning flexible elongated items being drawn from a supply.
BACKGROUND OF THE INVENTION
In the laying of communication lines, for example, optical fiber networks or conventional copper wire lines, as well as power cables, it is often convenient to position the lines or power cables below ground within a duct that isolates and protects the lines from moisture, dirt, corrosion, rot, attack from animals and other hazards. Ducts carrying communication lines and the like may have exceedingly long runs and are accessible only at isolated points along their length, for example, at points where they are connected to components of the network, such as amplifiers or transformers or installations to which they provide a service, such as power or communications.
Due to the limited accessibility to the ducts, the lines must be pulled through the ducts from one access point to another. It is advantageous to first install a plurality of flexible, protective, tubular sleeves within the ducts. The sleeves are preferably woven of polymeric material having adequate tensile strength to withstand the stresses encountered when pulled through a long duct during installation. The sleeves are also preferably abrasion resistant so as to withstand any friction generated during installation between the sleeves and the duct as well as other sleeves or lines within the duct. Each sleeve has a pre-positioned pull cord within its bore. When it is desired to install an optical fiber cable, for example, the cable is attached to one end of a pull cord and the other end of the pull cord is drawn through the sleeve within the duct. The sleeves protect the cables within the duct from abrasion when cables or lines are installed and also help organize the space within the duct.
It is convenient to install three to four sleeves simultaneously in a duct. The sleeves are provided from a supply reel and are attached to one another at one end. This end is drawn through the duct. However, because the sleeves are flexible and are being drawn from a spool, they may occasionally twist, kink, tangle or become otherwise misaligned with one another. It is desirable to have multiple sleeves lie neatly atop one another during the pull through a duct, both to conserve space in what may be a crowded duct, and to keep the tension force of the pull as low as possible. Knots, twists, kinks, tangles or other irregularities which may form during the pull are to be avoided since they will occupy otherwise useable space and may cause increased drag during the pull. Increased drag may lead to over-stressing of the sleeves and their parting. This is especially inconvenient for long pulls because the sleeves must be recovered from the duct and another pull then attempted.
It is desirable to prevent misalignments such as tangles, twists, kinks and other irregularities during the installation of protective sleeves in ducts.
SUMMARY OF THE INVENTION
The invention concerns a tool for aligning a plurality of flexible elongated items being pulled from a supply. The tool comprises a body defining a plurality of openings adjacent to one another. The openings receive the elongated items drawn through the tool. The body is angularly adjustable relatively to the elongated items about an axis extending widthwise across the elongated items. Adjustment of the body's angular orientation varies the apparent size of the openings to accommodate elongated items having a varying thickness. The body guides the elongated items into alignment with one another when the elongated items are drawn through the openings.
In one embodiment, the body comprises a plate having a plurality of openings arranged adjacent to one another.
In another embodiment, the tool comprises first and second elongated frame members positioned in spaced apart relation to one another. A plurality of elongated cross pieces are engaged with the first and second frame members and extend between them. The cross pieces are positioned in spaced apart relation to one another and define a plurality of openings for receiving the elongated items. The frame members are angularly adjustable relatively to the elongated items about an axis parallel to one of the cross pieces so as to vary the apparent size of the openings to accommodate the elongated items having varying thickness. The cross pieces and the frame members guide the elongated items into alignment with one another when the elongated items are drawn through the openings.
The invention also concerns a method of positioning a plurality of elongated items in a duct. The method comprises the steps of:
- (A) positioning a tool proximate to an entrance of the duct, the tool defining a plurality of openings for receiving and aligning the elongated items;
- (B) threading the plurality of elongated items through the openings;
- (C) drawing the elongated items through the tool and the duct, the items being aligned with one another upon passage through the openings; and
- (D) adjusting the orientation angle between the tool and the elongated items, thereby changing the apparent size of the openings engaged by the elongated items to accommodate items of varying thickness.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of elongated protective sleeves being drawn into a duct;
FIG. 2 is a front view of an alignment tool according to the invention;
FIG. 2A shows an alignment tool used with a cross bar;
FIG. 2B shows and alignment tool mounted on support stanchions;
FIG. 3 is a front view of the alignment tool shown in FIG. 2 in an open configuration;
FIGS. 4 and 5 are side views of the alignment tool of FIG. 1 in use; and
FIGS. 6 and 7 are front views of an alternate embodiment of an alignment tool according to the invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
FIG. 1 illustrates an installation operation wherein multiple protective sleeves 10 are pulled from a supply, such as one or more spools 12, and drawn through a duct 14. Each sleeve 10 is biased into a flat, collapsed configuration so that it occupies a minimum of space within duct 14 and presents as little drag as possible. This uses the limited space within duct 14 efficiently and keeps the pulling force required to draw the sleeves through the duct as low as possible so as not to induce significant stress on the sleeves, possibly causing them to part. Each sleeve 10 has a pull cord within it to facilitate drawing optical fiber cables, copper wire telephone lines, or power cables through the sleeves once they are positioned within the duct 14. Sleeves 10 expand flexibly to accommodate the cable or wires positioned within them.
For efficiency and convenience, multiple sleeves 10 are drawn simultaneously by attaching the sleeves together at one end and drawing them together through the duct 14. Because of the manner in which the sleeves are wound onto the spool 12, from time to time, certain of the sleeves 10 will become slack while others remain taut. The slack sleeve or sleeves may twist, kink or tangle and thereby enter the duct 14 misaligned in relation to the taut sleeves. It is desirable to avoid misalignments between the sleeves 10 during installation in the duct 14 because it is difficult, and sometimes impossible, to draw the optical fibers, copper wires or power cables through a kinked, tangled or twisted sleeve using the pull cord. Furthermore, misaligned sleeves occupy more space than aligned sleeves and cause more drag during the pull, thereby inducing higher stresses on the sleeves. To prevent misalignment of sleeves 10 when entering duct 14, an alignment tool 18 is used. The tool 18 is positioned between the spool 12 and the duct 14, generally proximate to the duct. As described in detail below, the sleeves are fed continuously through the alignment tool 18 which eliminates any twists, kinks, tangles or other misalignments between the sleeves 10 before they enter the duct.
An embodiment of alignment tool 18 is shown in detail in FIG. 2. Tool 18 has a pair of frame members 20 and 22 positioned in spaced apart relation to one another. Preferably, the frame members 20 and 22 are substantially co-planar and parallel to each other and spaced apart such that the distance 24 between them is substantially equal to the width of the widest of the items being drawn. In this example, sleeves 10, shown in phantom line, are all of equal width, but tool 18 may also be used with items of different width. A plurality of cross pieces 26 is engaged with the frame members 20 and 22. The cross pieces 26 extend between the two frame members 20 and 22 and define a plurality of openings 28 that receive the sleeves 10. Preferably, at least three openings 28 are defined between the frame members 20 and 22.
When multiple sleeves are drawn simultaneously through a duct, the ends of the sleeves are joined together. Thus, to enable the sleeves 10 to be threaded into the openings 28 of tool 18 without access to the free ends of the sleeves, it is convenient to provide the capability for disengaging one of the frame members, such as 20, from the cross pieces 26 in order to provide access to openings 28. One method of doing this is to fixedly attach all of the cross pieces 26 to frame member 22, and releasably attach the cross pieces to frame member 20. This may be done in any number of ways, for example, by welding or bonding the cross pieces to frame member 22 and using threaded fasteners or quick-release detent mechanisms to attach the cross pieces to frame member 20.
While practical, the above-described configuration leads to a two-piece tool. This is disadvantageous for field use as one of the frame members 20 or 22 could become separated from the other and lost. Therefore, the tool embodiment shown in FIGS. 2 and 3 and described below, which does not suffer from this disadvantage, is preferred.
As shown in FIG. 3, in the presently preferred embodiment, all but one of the cross pieces 26 are fixedly attached to frame member 22. One cross piece, denoted as 26a, is fixedly attached to frame member 20 and releasably attached to frame member 22. Attachment of cross piece 26a to frame member 22 is preferably effected by mounting a threaded shaft 30 on the end of cross piece 26a that engages frame member 22. Threaded shaft 30 extends outwardly through frame member 22 and is engaged by a compatibly threaded nut 32 having a knurled knob 34 to facilitate manual turning of the nut. As shown in FIG. 2, nut 32 bears against frame member 22 upon tightening and, being fixedly attached to frame member 20, draws and holds that frame member into engagement with cross pieces 26.
Conversion of the tool 18 between the closed configuration, shown in FIG. 2, and the open configuration of FIG. 3, is effected by manually loosening nut 32 using knob 34. This will allow frame member 20 to be moved away from frame member 22 and disengaged from cross pieces 26, except for cross piece 26a, to which it is fixedly attached. The frame member 20 may then be rotated about cross piece 26a relative to frame member 22 to provide free access to openings 28. This position of frame member 20 is shown in FIG. 3. Once the sleeves 10 are threaded into openings 28, the tool 10 may be brought back to the closed configuration by rotating frame member 20 parallel with frame member 22, engaging frame member 20 with cross pieces 26, and tightening nut 32. To facilitate engagement of the cross pieces 26 with frame member 20, a plurality of holes 36 are positioned in spaced apart relation along the length of the frame member, the spacing of holes 36 corresponding to the spacing of the cross pieces 26.
As shown in FIG. 2, tool 18 has a pair of handles 38 and 40 to provide a gripping region allowing manual control of the tool. Preferably, handles 38 and 40 are attached to respective frame members 20 and 22 via a reverse bend portion 38a and 40a respectively. The reverse bend allows the handles 38 and 40 to be angularly oriented with respect to the frame members 20 and 22.
Preferably, tool 18 includes a pair of stabilizer bars 41 and 43. Bar 41 extends between handle 38 and frame member 20, and bar 43 extends between handle 40 and frame member 22. As shown in FIGS. 2A and 2B, the stabilizer bars facilitate mounting the tool 18 on support means such as the cross bar 45, which passes through an aperture defined between the stabilizer bars and the reverse bends 38a and 40a of handles 38 and 40. FIG. 2B shows the stabilizer bars providing a mount for attachment of the tool to stanchions 47. Such mountings may be used to reduce operator fatigue when long pulls are necessary.
Use of tool 18 to align sleeves 10 being pulled from a supply and drawn into a duct is illustrated in FIGS. 4 and 5. As shown in FIG. 4, sleeves 10 are pulled in the direction indicated by arrow 42 through openings 28 defined by cross pieces 26. The angular orientation of tool 18, as measured by the angle 44 between the frame members 20 or 22 and the sleeves 10, is manually adjusted using handles 38 and 40 so as to vary the apparent size of openings 28 relative to the thickness of the sleeves 10. Normally, with the sleeves 10 being biased into a flat configuration as noted above, the orientation angle 44 is relatively acute so as to present small apparent openings 28 to the sleeves 10. This allows the cross pieces 26 and the frame members 20 and 22 to act as guides, engaging the sleeves 10 and straightening any twists, kinks and tangles and thus align the sleeves 10 with one another before they enter the duct. However, occasionally there will be a variation in the thickness of a sleeve 10, as illustrated by the bulge 46. Bulge 46 may be caused, for example, by a splice in the pull cord positioned within each sleeve 10, the splice requiring a knot which manifests itself as a bulge in the thickness of the sleeve. To accommodate this bulge, the tool 18 is rotated in the direction indicated by arrow 48 as shown in FIG. 5, so that the apparent size of openings 28, as seen by the sleeves 10, is larger than when the orientation angle 44 is more acute. Rotating the tool 18 allows the bulge 46 to pass through the opening 28. Once the bulge has passed, the tool 18 may be rotated back to the more acute angle 44 shown in FIG. 4 until the next bulge 46 approaches.
It is observed that if the tool 18 is positioned with the handles 38 and 40 above the sleeves 10 and the reverse bend portions 38a and 40a are tilted in the direction of motion 42 of sleeves 10 (see FIG. 4), then the natural rotational motion of the tool 18, induced when a bulge 46 encounters a cross piece 26, will be in the direction of arrow 48 (see FIG. 5) and tend to increase the orientation angle 44 and consequently increase the apparent size of openings 28 to allow the bulge 46 to pass through. Reversing either the direction of motion 42 or the orientation angle 44 will result in contact between a bulge 46 and a cross piece 26 tending to rotate the tool 18 in a direction that will decrease the apparent size of the openings 28 and thereby snag the tool on the sleeves 10. It is desirable to avoid this situation by proper use of the tool 18 as illustrated in FIGS. 4 and 5.
FIGS. 6 and 7 show another embodiment 50 of the alignment tool according to the invention. Tool 50 comprises a body, preferably in the form of a plate 52 having a plurality of openings 54 for receiving the sleeves 10, shown in phantom line. The plate 52 has additional openings 56 positioned along opposite edges and sized to allow the plate to be manually held during sleeve installation. Similar to the embodiment 18 described above, the plate 52 may be angularly oriented with respect to the sleeves to vary the apparent size of the openings 54 to accommodate the thickness of sleeves 10.
As shown in FIG. 7, a portion 58 of the plate 52 may be attached to the plate by a hinge 60 to permit disengagement of the portion and thereby provide access to the openings 54 and allow sleeves 10 to be threaded through the openings without access to free ends of the sleeves.
Alignment tools as described above facilitate the installation of protective sleeves within duct work and ensure the efficient use of space within the duct.
Patent Application
20050127237
