Abstract:
During the stringing of fiber optic cable on utility poles, there is a need for making splices of that cable at each pole where a terminal is to be located for connection of that cable to, e.g., a house. Cable slack is needed for those splices, and certain lengths of slack are optimum. Apparatus and methodology for enabling a lineman to make accurate and convenient optimum length measurements of a slack portion of fiber optic cable during the stringing of the cable on utility poles is disclosed.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to installation of fiber optic cable on poles elevated above ground and, more particularly, relates to a safe and convenient technique for providing accurate cable slack lengths at certain locations along the path of that installation. 
         [0003]    2. Description of Prior Art 
         [0004]    In this modern world of improved communication, it is commonplace to see cables strung on utility poles, high above ground. These cables can be used for TV, telephone, fax, and/or Internet communication, etc. The latest kind of cable to be used for these communication purposes may be a fiber optic cable. 
         [0005]    When fiber optic cable is used for this purpose, cable splicing is generally required at certain locations where the cable is to be communicatively-connected to a terminal, typically at the location of each utility pole and elevated above ground. To accomplish this, a certain amount of cable slack is required to be positioned at the top of each utility pole to enable the cable stringer (lineman or technician or installer), positioned high above ground, to make the appropriate splice. Based on experience, a certain amount of cable length slack is optimum for this splicing purpose, e.g., five feet of slack for a particular kind of fiber-optic cable. 
         [0006]    Currently, the lineman merely guesses at this length or, if he/she has a tape measure, ruler, or other measuring device, attempts to make an accurate five-foot measurement of the cable while positioned high above ground in an aerial bucket or while hanging from the pole. These prior art techniques are problematical. For example, if the guesstimate of the slack is too long, cable is wasted and, if a sufficient number of cable slack guesstimates are too long, there may not be sufficient overall cable length to finish the stringing of the cable along the poles of the intended installation route. On the other hand, if the guesstimate is too short at any particular terminal location, then there may not be sufficient slack cable to allow the subsequent splice to be properly made; the splice may be prone to failure because the glass fiber strands may break if the cable needs to be bent to, or beyond, its bending limits in order to accomplish the splice. Moreover, juggling a measuring device to measure a length of cable while hovering in an aerial bucket, or while hanging from a utility pole, may not be safe or convenient under all conditions. A better way of making a cable slack measurement under aerial installation conditions is needed. Applicant provides a solution to this problem of the prior art. 
       SUMMARY OF THE INVENTION 
       [0007]    Embodiments of the present invention include methodology and apparatus for accurately and conveniently providing a pre-determined length of slack of a fiber optic cable. 
         [0008]    The method includes wrapping the cable around a template which has receptacles for the cable. The template is pre-adjusted to provide the pre-determined length when the cable is wrapped a pre-determined number of times through the receptacles, providing a wrapped cable length. The wrapped cable length is clamped to the receptacles and tied in a manner to preserve that length when the clamps are removed. The clamps are removed thereby providing the pre-determined length of fiber optic cable slack. In a particular embodiment, the predetermined number of times is one time—i.e., one wrap. This methodology is particularly useful when the fiber optic cable is being strung from one utility pole to another, the slack of the fiber optic cable being deposited atop a utility pole. 
         [0009]    The apparatus enables a lineman to make an accurate and convenient length measurement of a slack portion of a fiber optic cable during the stringing of the cable on utility poles, generally high above ground. The apparatus includes a centralized hub and a number of spokes or arms emanating from the hub in directions which are substantially coplanar. In other words, the spokes or arms lie in a plane, generally speaking. There are an equal number of clamps for clamping the cable in place, each one of the clamps being positioned at the end of a different one of the spokes. The lengths of all of the spokes with their respective clamps are equal to each other and are pre-determined to provide a suitable length of the slack portion of the fiber optic cable when all of the clamps engage the cable. As a result, a portion of the fiber optic cable is formed into a generally circular shape while being held by the clamps and the axial circumference of the portion is equivalent to the suitable length of the slack portion. 
         [0010]    In further features of the present invention, the portion of fiber optic cable is tied in a manner to fix its length at the suitable length after removing the clamps from the cable, and that portion is stored at the top of one of the utility poles. The centralized hub includes a handle arranged to be grasped by the lineman while positioning the cable in the clamps. Or, the apparatus can be temporarily fastened to one of the poles, while the lineman is positioning the cable in the clamps, by a threaded bolt and nut combination, either the bolt or the nut being affixed to the pole and the other being affixed to the centralized hub. The length of each of the spokes can be adjusted. For example, the spokes can telescope, whereby the length of the spokes can be held in place by a pin inserted through holes in the telescoping spoke or by friction force as may be applied by a wing-nut on the telescoping spoke. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  depicts a series of utility poles supporting fiber optic cable in which the present invention is particularly useful; 
           [0012]      FIG. 2  is a perspective view of the apparatus of the present invention showing clamps at the ends of the extendible arms of the apparatus in an open condition; 
           [0013]      FIG. 3  is an edge view of one clamp of  FIG. 2  in an open state; 
           [0014]      FIG. 4  is an edge view of the clamp of  FIG. 3  in a closed state; and, 
           [0015]      FIG. 5  is the apparatus of  FIG. 2  shown supporting a fiber optic cable with clamps in their closed state. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0016]    Referring to  FIG. 1 , fiber-optic cable system  100  depicts a series of utility poles  101 ,  102  and  103  supporting fiber optic cable  105  above ground line  104 , with which the present invention is particularly useful. It is to be understood that many utility poles can be used and is not limited to three in number. As can be seen at the top of each of the poles, there is a loop of cable slack shown, i.e., loops  106  atop pole  101 , loop  107  atop pole  102  and loop  108  atop pole  103 . The slack is needed for splicing purposes, to splice cable  105  with another cable (not shown) and thereby communicatively connect cable  105  to, e.g., house  109  via that other cable which is operatively-connected to the house. 
         [0017]    The detail of how each slack loop is fastened to the pole top is not shown, but in a particular embodiment, there may be another cable or bare strand (not shown) used specifically for support. The support cable may also run from pole-top to pole-top in a manner similar to fiber optic cable  105  and, in such a case, would then be used to support fiber optic cable  105  in each span between adjacent poles. Alternatively, the support cable may be individually deployed at each pole-top. The slack loop may be direct lashed to this support cable. A lineman, or technician, or cable installer either climbs each pole or uses an aerial bucket to achieve pole-top height and access. 
         [0018]    Referring to  FIG. 2 , a fiber-optic cable slack measuring device  200  is depicted in perspective view. Centralized hub  201  is formed from fixed-length arms or spokes  202   203 ,  204  and  205 . Handle  206  is affixed to centralized hub  201 . Slideable spokes or arms  207 ,  208 ,  209  and  210  nest or telescope into and out from fixed arms  202 ,  203 ,  204  and  205  respectively. Slideable spokes can be held in place by pins inserted in holes, such as pins  202 A,  203 A,  204 A and  205 A, inserted in holes  202 B,  203 B,  204 B and  205 B, respectively. 
         [0019]    Permanently affixed to the ends of slide-able spokes  207 ,  208 ,  209  and  210  are cable clamping mechanisms  211 ,  212 ,  213  and  214 . Each cable clamping mechanism comprises a square-shaped or rectangular -shaped aperture when closed shut and includes two hinged axes of rotation. That is, clamping mechanism  211  includes hinges  215 A and  215 B, clamping mechanism  212  includes hinges  216 A and  216 B, clamping mechanism  213  includes hinges  217 A and  217 B and clamping mechanism  214  includes hinges  218 A and  218 B. Using clamping mechanism  212  at the top of  FIG. 2  as an illustrative example, there is rotational motion of a portion of clamping mechanism  212  around the axis formed by hinge  216 A. There is also rotational motion of a portion of clamping mechanism  212  around the axis formed by hinge  216 B. 
         [0020]    Referring to  FIGS. 3 and 4 , clamping mechanism  212  is shown schematically in edge view in open and closed states or positions, respectively. In  FIG. 3 , clamp floor  301  and clamp wall  302  are fixedly connected to each other and to extendible arm  208 . They can all be formed from one-piece metal or hard plastic construction. Clamp ceiling  303  and clamp wall  304  are also fixedly connected to each other and can also be formed from one piece metal or hard plastic construction and they rotate about hinge  216 A. Rotatable latch  305  is hinged to clamp wall  304  at hinge  216 B and rotates about the axis of that hinge. 
         [0021]    Referring to  FIG. 4 , clamping mechanism  212  is shown in a closed position, as it might be used in holding fiber optic cable  105  in place. Optical fiber  105  is shown in cross section within clamp  212 . In this closed position, the inner dimensions of clamping mechanism  212  are proper for snugging cable  305  therein without crushing or damaging the cable. The cable can fall within the clamping mechanism along a clamping mechanism diagonal as shown, (or the clamping mechanism can be configured to snug the cable in a non-diagonal manner, as shown in  FIG. 5 , to be discussed hereinbelow). 
         [0022]    Rotatable latch  305  closes against clamp floor  301  as shown to hold clamping mechanism  212  in a closed state by any one of several techniques. Latch  305  can be magnetic if clamping mechanism  212  is constructed from metal, whereby magnetic force can hold clamping mechanism  212  in a closed state. Alternatively, latch  305  can be spring-loaded to apply friction force to hold clamping mechanism  212  in a closed state. As another alternative, a tongue and groove (not shown) can be used between latch  305  and clamp floor  301  to keep latch  305  in place. If constructed from plastic, a button snap could be fashioned on latch  305  to connect with a mate on clamp floor  301  to keep latch  305  in place. Other means can also be used. 
         [0023]    Referring to  FIG. 5 , fiber optic cable  105  is shown in the circular shape that it would naturally form when engaging template or apparatus  200 . In this Figure, the clamping apertures when in a closed state are only large enough for cable  105  to be held in a side-by-side configuration, as contrasted with the diagonal configuration of  FIG. 4 . Temporary fastening means  501  is shown centrally-located in the centralized-hub portion of apparatus  200 , and can represent, a threaded bolt for connection to a like threaded nut on the pole, or some other fastening mechanism, like a hook or an eye for operation with a hook and eye mechanism. Handle  206  is not visible in this view. In clamping mechanism  212 , the edge of latch  305  and hinge  216 B are visible in this view in the closed state. The other clamps show hinges  215 B,  217 B and  218 B. 
         [0024]    Referring to  FIG. 2  and  FIG. 5  together, the pole to which cable slack measuring device  200  is temporarily connected is located on the side opposite handle  206 . Therefore, if temporary mounting to the pole is used by the technician, in order to provide easy access to open and close clamping mechanisms  212  and  214 , device  200  can be affixed to the pole in a manner so that it is oriented relative to the vertical pole, e.g., approximately forty-five degrees, so that spokes  203  and  205  are not vertical and not obstructed by the pole. The hook and eye mechanism can be configured a manner to automatically provide that approximate forty-five degree orientation for the device. 
         [0025]    In operation, a lineman (not shown in the Figures) would position himself or herself at the top of a utility pole, such as pole  107  and would either hold apparatus  200  by handle  206  or would fasten apparatus  200  to the utility pole by any of the temporary fastening means discussed above. Then the lineman would wrap cable  105  once through clamps  211 ,  212 ,  213 , and  214  to achieve the configuration shown in  FIG. 5 . Then the lineman would close all four clamps, with only clamp  212  containing two thicknesses of cable  105  as shown in cable cross-section in  FIG. 4 . The pressure or friction imposed on cable  105  by clamp  212  prevents the cable from moving while the lineman then tightly lashes or tapes the circular configuration together and then lashes or tapes it to either the pole atop which this activity is taking place or to a support cable attached to the top of this pole. After these lashings, the lineman removes template  200  by opening up all four clamps, leaving behind a length of cable slack which is optimum for splicing purposes for the particular cable being strung. It is not important that the configuration maintains a circular shape after template  200  is removed, although the resilience and flexibility of the cable tends to keep the slack in a generally circular shape. 
         [0026]    In a particular instance, a five ( 5 ) foot cable slack length is optimum, and this is achieved by adjusting movable arms  207 ,  208 ,  209  and  210  to positions where the distance from the middle of clamp  212  to the middle of clamp  214 , and where the distance from the middle of clamp  211  to the middle of clamp  213 , is approximately nineteen ( 19 ) inches. The familiar theorem for the circumference of a circle is relied upon where the circumference is equal to “ΠD.” “Π” is the familiar Greek letter identifying a constant relating to circles and having value of approximately 3.14, and where “D” is the diameter of the circle. This would produce an approximate sixty (60) inch (i.e., five foot) circumference which would then provide the sought-after five foot length of slack. 
         [0027]    Variations and alternative embodiments of this fiber optic cable slack measuring device informally dubbed the “Coilbeeler” are contemplated, and can be made without departing from the spirit and scope of the present invention as defined in the appended claims. The present embodiments are to be considered in all respects as illustrative and not restrictive. The scope of the invention, therefore, is indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.