Abstract:
A tool for adjusting a grip. The tool includes a tubular section for containing the grip while receiving a cable. A first stop is positioned in or near a first end of the tubular section to provide an opening for introducing the cable into the tubular section while the grip is contained in the tool. One of first and second stops is arranged for displacement along the longitudinal axis with respect to the other stop. With the grip positioned between the first and second stops, when one of the stops is displaced toward the other stop a force is applied against the grip, causing the size of the bore to increase and the length of the grip to be contracted.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates generally to cable grips of the type adapted to be expanded and contracted radially by endwise compression and extension and, more specifically, to methods and equipment for operating such grips. This application claims priority to and is a Divisional of U.S. application Ser. No. 13/176,116 filed Jul. 5, 2011, which is a Continuation of Ser. No. 12/581,313 filed Oct. 19, 2009, now U.S. Pat. No. 7,997,843 issued Aug. 16, 2011, and incorporated herein by reference in its entirety. 
       BACKGROUND 
       [0002]    Cable grips are used extensively in many industries to pull cable segments through conduit, along and between overhead towers, or in structural applications. Such grips are important tools for installation of both electrical and mechanical cables in, for example, bridge structures, hoisting and conveyor cables. Contemporary designs of cable grips were advanced during the first half of the twentieth century by Edgar Kellems, as described in part in U.S. Pat. Nos. 1,670,543, 1,886,026, and 2,664,609, each of which is incorporated herein by reference. 
         [0003]    Commonly, a grip has a bore at one end and an eye portion at a distal end. With a cable which is to be pulled or secured placed in the bore, the grip is tightened about the cable and the eye portion is attached to a hook, or another cable or another type of mechanical linkage, in order to place the grip under tension. Such grips are generally fashioned as woven wire tubes with meshes of wire much smaller in gauge than the size of the cable inserted within the bore. Commonly, such grips are available in a large variety of sizes for application to mechanical cable and electrical wire varying in radial dimension from relatively small sizes such as used in residential electrical applications to large dimensions on the order of about two inches (5.08 cm) or greater. Cable grips are useful for pulling, positioning, routing and providing for strain relief of cables. 
         [0004]    When attaching a grip to a cable, the grip is contracted along a longitudinal axis in order to enlarge the radial dimension of the bore about the longitudinal axis and thereby permit entry of the cable into the grip bore. Once the cable is positioned in the bore, the diameter of the bore opening is reduced to tighten the grip about the cable. Grips of this type are designed for limited ranges of cable size to assure that the grip can be used to reliably pull or secure the cable. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0005]    According to one embodiment of the invention a tool is provided for adjusting a grip to secure a cable within a bore in the grip surrounded by interlaced wiring. The grip is of the type which is extendable in length along a longitudinal direction so that, as the length of the grip is extended or contracted, the size of the bore is adjusted to a relatively large size in a radial direction to receive the cable or to a relatively small size in a radial direction to position the wiring against the cable. The grip has a characteristic external size in the radial direction when the bore is the relatively large size. The tool includes first and second tubular sections for containing the grip while receiving the cable into the bore, with each section having first and second ends. The second section is sized for positioning within the first section in a telescopic arrangement so that the sections provide an assembly extendable in length along a longitudinal axis. The first section has an interior dimension, in a radial direction transverse to the longitudinal axis, at least as large as the characteristic external size of the grip. The first section includes a first stop providing an opening that permits introducing the cable through the first end and into the first tubular section while the grip is contained in the tool so that movement of the grip out of the first tubular section through the first end is blocked. The second tubular section includes a second stop positioned in the second tubular section. With the grip positioned in the first and second tubular sections and between the first and second stops, when the second tubular section is displaced along the longitudinal axis and toward the first stop, a force is transferred against the grip, causing the size of the bore to increase. 
         [0006]    A related method is also provided for adjusting a grip to secure a cable within a bore in the grip. With the grip bore surrounded by interlaced wires, the grip is characterized by an extended length in a longitudinal direction when in a relaxed state and a contracted length in the longitudinal direction when in a compressed state. The grip has a characteristic external dimension, measureable in a radial direction transverse to the longitudinal axis. When the grip is in the compressed state, with the bore having a characteristic first relatively large dimension, the first relatively large dimension is of sufficient size that the cable can be received into the grip bore. The method includes providing first and second tubular sections each having first and second ends, with the second section sized for positioning within the first section in a telescopic arrangement so that the combination of sections provides an assembly extendable in length along a longitudinal axis. The first section has an interior dimension, in a radial direction transverse to the longitudinal axis, at least as large as the characteristic external dimension of the grip in the compressed state with the bore configured to the characteristic first relatively large dimension at which the cable can be received into the grip bore. With the second tubular section positioned within the first tubular section, the second tubular section is extended telescopically from the first tubular section so that the first and second sections additively provide an interior length along the longitudinal axis at least as long as the extended length of the grip when the grip is in the relaxed state. A first opening is provided at a first end of one of the tubular sections of such dimension as to permit entry of the grip into said one of the tubular sections. The grip is inserted through the first opening, into said one of the tubular sections and into the other of the tubular sections until the grip reaches a stopping point. The size of the first opening is reduced to confine the grip within said one of the tubular sections when a compressive force is applied to the grip from the first end of said one of the tubular sections. The second tubular section is displaced within the first tubular section to reduce the interior length additively provided by the first and second sections to less than the extended length of the grip when the grip is in the relaxed state. This displacing results in application of the compressive force to reduce the length of the grip. According to an embodiment of the method, with the length of the grip so reduced, the cable is inserted into the grip bore. 
         [0007]    In still another embodiment, a tool is provided for adjusting a grip to secure a cable within a bore in the grip surrounded by interlaced wiring. The grip is extendable in length along a longitudinal direction so that, as the length of the grip is extended or contracted, the size of the bore is adjusted in a radial direction transverse to the longitudinal direction to a relatively large size to receive the cable or to a relatively small size to position the wiring against the cable. The grip is of the type having a characteristic external size in the radial direction when the bore is the relatively large size. The tool includes a tubular section for containing the grip while receiving the cable into the bore. The tubular section has a length along a longitudinal axis and an interior dimension, in a radial direction transverse to the longitudinal axis, at least as large as the characteristic external size of the grip. A first stop is positioned in or near a first end of the tubular section to provide an opening that permits introducing the cable through the first end and into the tubular section while the grip is contained in the tool. Movement of the grip out of the first tubular section through the first end is thereby blocked. A second stop is positioned along the longitudinal axis wherein one of the first and second stops is arranged for displacement along the longitudinal axis with respect to the other stop. With the grip positioned in the tubular section and between the first and second stops, when one of the stops is displaced toward the other stop a force is applied against the grip, causing the size of the bore to increase and the length of the grip to be contracted. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout, and wherein: 
           [0009]      FIG. 1  is a simplified view of an adjustment tool, taken along a longitudinal axis, for insertion of cable into a grip according to one embodiment of the invention; 
           [0010]      FIG. 2  is a view in cross section of the tool shown in  FIG. 1 , taken along a direction transverse to the longitudinal axis; 
           [0011]      FIG. 3  is a perspective view of the tool shown in  FIG. 1  illustrating an exemplary plate mounted to partially close off an end of a section of the tool; 
           [0012]      FIGS. 4A-4C  illustrate one embodiment of a first stop in the form of a removable cap positioned at an end of a first section of the tool shown in  FIG. 1  wherein: 
           [0013]      FIG. 4A  is a view of the removable cap taken along the longitudinal axis of the tool; 
           [0014]      FIG. 4B  is a view in cross section taken along a direction perpendicular to the longitudinal axis, and 
           [0015]      FIG. 4C  is a perspective view of the installed cap; 
           [0016]      FIGS. 5A-5E  illustrate a second embodiment of a first stop positioned at an end of the first section of the tool shown in  FIG. 1  wherein: 
           [0017]      FIG. 5A  is a perspective view of the first stop in a closed configuration; 
           [0018]      FIG. 5B  is a second view of the first stop shown in  FIG. 5A , taken along the longitudinal axis of the tool, positioned about the end of the first section of the tool; 
           [0019]      FIG. 5C  is an end view of the first stop shown in  FIG. 5A , in a closed configuration, taken along a direction perpendicular to the longitudinal axis of the tool; and 
           [0020]      FIG. 5D  is a perspective view of the first stop in an open configuration, taken along the longitudinal axis of the tool, illustrating two ring halves  72 ,  74  hinged to a collar; and 
           [0021]      FIG. 5E  illustrates a pair of locking pins, each formed at an end of a segment of coiled wire; 
           [0022]      FIG. 6  is a second longitudinal view of the tool shown in  FIG. 1 , illustrating rigging cord and pulleys which effect movement of one section of the tool with respect to another section of the tool; 
           [0023]      FIG. 7A  is a longitudinal view of a grip in a straight configuration, extending along an axis A; 
           [0024]      FIG. 7B  illustrates the grip of  FIG. 7A  in a view taken along a direction perpendicular to the axis A; 
           [0025]      FIG. 8A  is a longitudinal view of a straight length of cable extending along an axis A, which may be inserted into the grip of  FIGS. 7 ; 
           [0026]      FIG. 8B  is a view in cross section of the cable shown in  FIG. 8A  taken along line  8 B- 8 B shown in  FIG. 8A  in a direction perpendicular to the axis; 
           [0027]      FIG. 9A  is a longitudinal view of the grip of  FIGS. 7  adjusted to a first length; 
           [0028]      FIG. 9B  is a view of the grip of  FIGS. 7  taken along line  9 B- 9 B shown in  FIG. 9A  in a direction perpendicular to the axis A when the grip is adjusted to the first length shown in  FIG. 9A ; 
           [0029]      FIG. 10A  is a longitudinal view of the grip of  FIGS. 7  adjusted to a second length; 
           [0030]      FIG. 10B  is a view of the grip of  FIGS. 7  taken along line  10 B- 10 B shown in  FIG. 10A  in a direction perpendicular to the axis A when the grip is adjusted to the second length shown in  FIG. 10A ; 
           [0031]      FIG. 11A  is a view in cross section of a tool according to another embodiment; 
           [0032]      FIG. 11B  is a view of the tool shown in  FIG. 11A  taken along a longitudinal axis; 
           [0033]      FIG. 11C  is a view of a stop shown in  FIG. 11A ; and 
           [0034]      FIG. 12  is a view in cross section of another embodiment of a tool according to the invention. 
       
    
    
       [0035]    In accordance with common practice, the various described features are not drawn to scale, but are drawn to emphasize specific features relevant to the invention. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0036]      FIG. 7A  illustrates a generic grip  2  exemplary of the type used to pull cable, including electrical wire, such as the segment of cable  4  shown in  FIGS. 8A and 8B . Grips of this type may be referred to as a multi-weave style. They are available from numerous providers including Brenco, Inc. of Harrison Ohio USA. In the view of  FIG. 7A  the grip  2  is positioned to extend longitudinally along a straight axis A. The grip has at a first end an integrally formed eye loop  3  into which a hook may be placed to pull the grip when the cable is attached to the grip. As more fully described herein, the portion of the grip extending from the eye loop to the opposing end is tubular. The exemplary segment of cable  4  is a straight length as shown in  FIG. 8A  which extends longitudinally along the straight axis A for insertion into the grip  2 . The segment of cable has a substantially circular profile in cross section with radius R as indicated in  FIG. 8B . As is well known, grips of this type comprise a number of individual cables or wires  8  which are interlaced with one another to fit around the cable segment. By interlaced it is meant that the wires  8  of the grip are crossed, passing over or under one another, or woven together, e.g., braided, or otherwise intertwined. The wires  8  may each be formed of a series of smaller gauge wires which are wound together in, for example, a spiral configuration. As shown in the view of  FIG. 7B , taken along a direction perpendicular to the axis A, the grip is essentially a tubular shaped sheath defining an interior bore, B, into which the cable  4  may be slid. Generally, the interlacing arrangement of the wires  8  to form the grip  2  provides an adjustable assembly that can be configured to provide a variable radial dimension to the bore B with a corresponding variable outside diameter OD 2  to the grip  2 . 
         [0037]    For example, as shown in  FIGS. 9A and 9B , the grip  2  may be adjusted to have a first length L 1 , as measured along the longitudinal axis A, for which length the bore B has a more or less circular shape extending a radial distance B 1  from the axis A. Referring next to  FIGS. 10A and 10B , the grip  2  may be contracted to a second, shorter length L 2 , also measured along the axis A, for which length the bore B again has a more or less circular shape. When the grip length is reduced to L 2  the bore expands from the radial dimension B 1  to a larger radial distance B 2  from the axis A. Compare  FIGS. 9B and 10B . Generally, so long as L 1  is greater than L 2 , the radial dimension B 2  is greater than the radial dimension B 1 . 
         [0038]    For a cable radius R, on the order of the radial dimension B 1 , when the grip bore is adjusted to the larger radial dimension B 2 , the cable  4  can be inserted into the bore. When the grip length is extended to reduce the bore size to the radial dimension B 1 , the interlaced wires can press against the inserted cable to firmly attach the grip to the cable as the grip is pulled with a force directed along the longitudinal axis A. 
         [0039]    According to an example embodiment of the invention, a partial and simplified view of an adjustment tool  10  for insertion of cable into a grip is shown in  FIG. 1 . The tool  10  comprises a pair of tubular sections  14  and  16 . The wall  18  of the section  14  has a cylindrically shaped inner surface  22 , within which the section  16  can be slid to extend and contract the tool  10  in a telescoping manner. Thus the length of the tool  10  is adjustable as measured along an axis  20  which is more or less central to the two sections  14  and  16 . The first tubular section  14  includes first and second opposing ends  26  and  28 , and the second tubular section includes first and second opposing ends  32  and  34 . The first end  26  of the section  14  has an opening  30 , the size of which may be defined by the inner wall surface  22  or which may be reduced relative to the diameter of the cylindrical shaped surface  22 . In the illustrated embodiments the opening  30  is sized such that when the bore B of the grip  2  is expanded to the larger radial dimension B 2 , the opening  30  is large enough to permit the grip  2  to pass through the opening  30 . 
         [0040]    According to one feature of the invention, the size of the effective opening, permitting entry of the grip  2  into or out of the section  14  through the end  26 , can be reduced. For example, a second opening, of reduced size relative to the opening  30 , can be formed at or about the end  26  of the section  14  by placement of a cap over the end  26 . The cap includes an opening of such reduced size as to permit insertion of the cable  4  through the cap and into the grip bore. The cap also confines movement of the grip after the grip is placed within the tool  10 . In the following example, the opening in the cap is smaller than the outside dimension B 1  of the grip  2 . Accordingly, when the bore B of the grip  2  is configured to the radial dimension B 1 , which is smaller than the dimension B 2 , the cap opening is of such reduced size relative to the opening  30  that the grip cannot pass through the cap. 
         [0041]    For the illustrated embodiments the sections  14  and  16  are cylindrically shaped lengths of pipe, e.g., comprising galvanized steel, aluminum or plastic. The section  16  has an outside diameter OD 16  smaller than the inside diameter ID 14  of the wall  18  of the tubular section  14 . With this arrangement the section  16  can slide along the inner wall surface  22  of the section  14 . See, also, the view in cross section of  FIG. 2  which illustrates this nested arrangement along a direction transverse to the axis  20 . The section  16  may have, for example, an outside diameter OD 16  of approximately 3.5 inches (8.8 cm) and an inside diameter ID 16  of approximately 3.25 inches (8.3 cm). The section  14  may have, for example, an outside diameter OD 14  of approximately 4 inches (10.2 cm) and an inside diameter ID 14  of approximately 3.75 inches (9.5 cm). 
         [0042]    As per the example embodiments illustrated in  FIGS. 3 ,  4 A- 4 C and  5 A- 5 E, the tool  10  includes a first stop  40  mounted at or near the first end  26  of the section  14  and a second stop  46  positioned along the second section  16  at or near the second end  34 . The first stop  40  can be placed at a variety of positions near the end  26  of the section  14  and the second stop can be placed at a variety of positions near the end  34  of the section  16 . The tool  10  is shown in  FIG. 1  with the first end  32  of the second section  16  extending through the second end  28  and partly into the first section  14 . When the section  16  is further displaced toward the first end  26 , the second stop  46  is also displaced toward the first end  26  thereby reducing the distance between the first stop  40  and the second stop  46 . The second stop  46  may be a plate  48  covering the opening  47  of the pipe section  16  at the second end  34 . When the section  16  is formed of steel pipe, the plate  48  forming the stop can be welded to close off the end  34 . See, for example, the perspective view of the section  16  shown in  FIG. 3 , which illustrates a plate  48  mounted to partially or completely close off the opening  47  at the end  34  of the section  16 . In other embodiments the plate  48  may be attached to the end of the section  16  with removable fasteners or may be a threaded end cap. More generally, the stop  46  is positioned to prevent the grip  2  from passing through the second end  34  of the section  16 . For example, with the grip  2  expanded to the length L 2  and inserted into the tool through the opening  30 , when the section  16  is displaced toward the first end  26  of the first section  14 , the second stop  46  can transfer forces along the direction of the axis  20  from the section  16  to the grip as the second stop  46  moves toward the first end  26 . 
         [0043]    With the sections  14  and  16  each formed in accord with cylindrical pipe geometries, the first stop  40  may be a threaded end cap  50  such as shown in the cross sectional view of  FIG. 4A , taken along the axis  20 . The exemplary cap  50  has an inside diameter ID 50  slightly larger than the outside diameter OD 14  of the section  14  and includes threads  52  along an interior surface  54  thereof so that the cap can be threaded over mating threads  56  formed on the exterior surface  60  of the section  14  along the end  26 . The cap  50  includes an aperture  66  of reduced size relative to the opening  30 . See, also, the cross sectional view of  FIG. 4B  taken along a direction perpendicular to the axis  20  and along the aperture  66 . 
         [0044]    With the cap  50  threaded on the section end  26 , as shown in the perspective view of  FIG. 4C , and with the grip  2  positioned within the tool  10  (not shown), the aperture  66  provides an effective opening size which permits insertion of the cable  4  into the grip bore while at the same time confining movement of the grip within the tool  10 . With the cap  50  removed from the end  26  of the section  14 , the grip can be moved in or out of the tool  10  through the larger opening  30  at the end  26  of the section  14 . In this example, the aperture  66  is circular in shape with a diameter D 66  larger than the outside dimension,  2 R, of the cable  4 , but is smaller than the inside diameter ID 14  of the tubular section  14 . 
         [0045]    For the illustrated embodiments, the aperture diameter D 66  is also smaller than the outside radial dimension of the grip  2  (measured from the axis A in a plane perpendicular to the axis A) when the grip bore extends the radial distance B 2  from the axis A, i.e., when the grip is reduced to the shorter length L 2 . Also for the illustrated embodiments, when the grip bore is configured to extend only to the smaller radial distance B 1 , the cap aperture  66  is then also too small to permit the grip to pass through the cap. 
         [0046]    According to an alternate embodiment of the first stop  40 ,  FIGS. 5A-5E  illustrate a two piece end cap  70  attached to the end  26  of the section  14 . The cap  70  comprises a ring-like structure formed in two ring halves  72  and  74  which are each hinged to a first collar  78 . The collar  78  is of cylindrical shape having an inside diameter slightly larger than the outside diameter, OD 14 , of the tool section  14  so that the collar  78  can be mounted on the exterior surface  60  of the section  14  along the end  26 . By way of example, with the section  14  and the collar  78  each fabricated from segments of cylindrically-shaped steel pipe having different diameters, the collar can be welded to the section  14  or may be attached to the section  14  with fasteners. Each of the ring halves  72  and  74  is also of cylindrical shape (e.g., in the shape of a half cylinder), and can also be fabricated from a section  82  of pipe having the same inside diameter as the collar  78 . Each section  82  may be cut from the cylindrically-shaped pipe to provide a half cylinder shape as shown in  FIGS. 5 . A flat plate  84  having the contour of a half of a ring, e.g., the shape of a letter “C”, is welded to an end of each section  82 . As now described, with the cap installed along the end  26  of the section  14 , and with a section  82  and a plate  84  forming each of the ring halves  72 ,  74 , the ring halves are brought together by means of hinge mechanisms, and the plates provide the first stop  40 . An aperture  86  is formed in the first stop through which the cable  4  can be inserted into the tool section  14 . 
         [0047]    Each of two hinges  80  connects one of the two ring halves  72 ,  74  to the collar  78 . See the perspective view of  FIG. 5A  and the elevation view of  FIG. 5B , taken along the axis  20 . The ring halves  72 ,  74  are shown in a closed configuration wherein the plates  84  have reduced the effective opening to the end  26  of the section  14 . In the closed configuration of  FIGS. 5A and 5B , the ring halves have come together to form the complete ring cap  70  with the reduced effective opening. When the cap  70  is closed the pair of plates  84  meet to form a complete, but segmented ring having a circular cap aperture  86  with a diameter D 86  larger than the outside dimension,  2 R, of the cable  4 . The diameter D 86  is smaller than the inside diameter ID 14  of the tubular section  14  and smaller than the largest outside radial dimension of the grip  2  (again measured from the axis A in a plane perpendicular to the axis A) when the grip is reduced to the shorter length L 2 . Preferably, when the grip bore, B, is configured to the smaller radial dimension B  1 , the cap aperture  86  formed by the two piece end cap  70  is also too small to permit the grip  2  to pass through the cap  70 . 
         [0048]    The ring halves  72 ,  74  can be secured in the closed configuration by inserting a pair of locking pins  90  through each ring half and into the wall  18  of the section  14 . In the example shown in the figures, a pair of ring apertures  92  are formed in each of the ring halves. See  FIG. 5C  which provides an end view of the two ring halves  72 ,  74  in the closed configuration of  FIGS. 5A and 5B  mounted on the tool section  14 . The view of  FIG. 5C  is taken through a portion of the axis  20  within the section  14  without showing the section wall  18 . Each hinge  80  is mounted about a point of symmetry  88  along each half cylinder shape of a section  82 . Each section  82 , being in the shape of a half cylinder, is an arc extending from the point of symmetry  88  some ninety degrees about the axis  20  in each direction with respect to the point of symmetry  88 . The ring apertures  92  of each section are formed about  80  degrees from the point of symmetry  88 , near an end of the arc of the half cylinder shape. In other embodiments the cylindrically shaped sections need not be identical and the cap  70  need not have symmetrically formed components. 
         [0049]    The locking pins  90  can each be reversibly placed through one of the ring apertures  92  formed in the sections  82  and further into wall apertures  94  (shown in  FIG. 5D ) formed in the wall  18  along the end  26  of the section  14 . The wall apertures  94  are each formed in the tool section  14  along the end  26 . The wall apertures are positioned in the section  14  for alignment with the corresponding ring apertures  92  formed in the sections  82  when the two ring halves  72 ,  74  are in the closed configuration of  FIGS. 5A and 5B . 
         [0050]    A pair of the ring apertures  92  and a pair of the wall apertures  94  are shown in the perspective view of  FIG. 5D  which illustrates the ring halves  72 ,  74  in an open configuration. In this open configuration the ring halves  70 ,  72  have been swung outward and away from the larger opening  30  of the section  14  so that the grip  2  can be moved in or out of the tool  10  through the opening  30 . In this example, with the cap aperture  86  being circular in shape, the aperture  86  has a diameter D 86  which is larger than the outside dimension of the cable  4  but smaller than the inside diameter ID 14  of the tubular section  14  and smaller than the outside dimension of the grip  2  when the grip is reduced to the shorter length L 2 . Preferably, even when the grip bore is configured to the smaller radial dimension B 1 , the cap aperture  86  is too small to permit the grip to pass through the cap. Generally, for both of the disclosed embodiments of the stop  40  (i.e., see  FIGS. 4A-C  and  5 A-E), with the grip  2  having an approximately circular shape about the bore and a length L 2 , the aperture  66  of the cap  50  and the aperture  86  of the cap  70  are, preferably, sized such that the outside diameter OD 2  of the grip is too large to fit through the cap apertures. 
         [0051]    When the two piece end cap  70  is swung from the open configuration of  FIG. 5D  to the fully closed position shown in  FIGS. 5A and 5B , the first and second ring halves  72 ,  74  of the end cap  70  are securely positioned about the opening  30  by placement of the locking pins  90  through the ring apertures  92  and into the wall apertures  94 . The locking pins  90  may, as illustrated in  FIG. 5E , be formed in pairs as opposing ends  96 ,  98  of a segment of stiff coiled wire  100  providing spring resilience. The gauge of the coiled wire and the size of the apertures are selected so that the wire ends  96 ,  98  are insertable within the ring apertures and the wall apertures to provide a snug fit. The segments of coiled wire  100  can be tethered to the first collar  78  with a clamping cable assembly that is fastened to both the collar and the coiled wire  100 . 
         [0052]    In the configuration of  FIGS. 5A ,  5 B and  5 C, the “C” shaped flat plates  84  have come together to form a complete ring-shaped cover which reduces the effective opening at the section end  26  to the diameter D 86  of the aperture  86 . Generally, when the first and second ring halves  72 ,  74  of the end cap  70  are in the closed position over the opening  30 , the flat plates  84  are positioned to extend inward from the surface  20  of the wall  18  of the tubular section  14  to provide an opening at or near the first end  26  which is smaller in diameter than ID 14 . 
         [0053]    Next, referring to  FIG. 6 , the tool  10  is shown to also include tackle comprising rigging cord and pulleys to effect movement of the tubular section  16  with respect to the tubular section  14 .  FIG. 6 , a longitudinal view of the tool  10  along the axis  20 , illustrates a first pair of pulley blocks  102 ,  104  positioned along the end  26  of the section  14  and a second pair of pulley blocks  106 ,  108  positioned along the end  34  of the section  16 . 
         [0054]    Noting that the second section  16  can be rotated about the axis  20  with respect to the first section  14 , the pulley block  102  of the first pair is rotationally aligned with the pulley block  106  of the second pair for movement of a first cord segment  114 . Similarly, the pulley block  104  of the first pair is rotationally aligned with the pulley block  108  of the second pair for movement of a second cord segment  116 . Along the second end  28  of the section  14  a second collar  118  is formed over the outside surface  22  of the section  14 . The second collar  118 , like the first collar  78 , is of cylindrical shape having an inside diameter approximately equal to the outside diameter, OD 14 , of the section  14 . 
         [0055]    The collar  118  is mounted on the exterior surface  60  of the section  14  along the end  28  of the section  14 . By way of example, with the section  14  and the second collar  118  each fabricated from segments of steel cylindrically-shaped pipe having different diameters, the second collar  118  can be welded to the section  14  or may be attached to the section  14  with fasteners. On the mounted second collar  118  there are positioned a pair of eyelets  120 ,  122 . The eyelet  120  is rotationally aligned about the axis  20  with the pulley blocks  102 ,  106  so that the cord segment  114  can be extended in a more or less straight path from the eyelet  120 , the cord segment  114  passing through the pulley block  106  and then through the pulley block  102 . Similarly, the eyelet  122  is aligned about the axis  20  with the pulley blocks  104 ,  108  so that the cord segment  116  can be extended in a more or less straight path from the eyelet  122 , the cord segment  116  passing through the pulley block  108  and then through the pulley block  104 . The cord segment  114  may be tied to the eyelet  120 . Similarly, the cord segment  116  may be tied to the eyelet  122 . In an alternate design, the cord segments  114  and  116  may be part of one continuous cord length with each cord segment passing through one of the eyelets, then around a portion of the second collar  118  to the other cord segment. 
         [0056]    The cord segment  114  extends from the eyelet  120 , through the pulley block  106 , through the pulley block  102  and to a tie point  124 . Similarly, the cord segment  116  extends from the eyelet  122 , through the pulley block  108 , through the pulley block  104  and to the tie point  124 . At the tie point  124  the two cord segments  114  and  116  may be braided together to form one pull segment. In an alternate arrangement as shown in  FIG. 6 , the two cord segments  114  and  116  may be tied to a ring  128  at the tie point  124 . A first end of a pull cord  130  is also tied to the ring  128  to provide a single pull line that can be used to exert a force against the eyelets  120  and  122  and against the second end  128 , which force causes movement of the tool section  16  toward the first stop  40 , e.g., the cap  70 . During use of the tool  10  the pull cord  130  extends from the tie ring  128  along both of the sections  114  and  116  toward and beyond the end  34  of the second section  16 . A grip handle  136  is attached to a second end of the pull cord opposite the first end which is tied to the ring  128 . With this arrangement, when the pull cord  130  is tensioned by applying a force to the grip handle  136  in the direction of the tool axis  20 , the tie point  124  and the ring  128  are centrally located along the tool section  14  between the pairs of pulley blocks  102 ,  104  and  106 ,  108 . 
         [0057]    An exemplary tool  10  has been described for adjusting a grip of the type used to firmly hold a cable for purposes of pulling or tensioning the cable. According to one embodiment, a method for adjusting the grip begins with adjusting the tool to extend the section  16  outward from the section  14  so that the length of the tool  10 , as measured between the first stop  40 / 56  and the second stop  46  is at least as long as the grip  2  when the grip is in a relaxed state. The end  26  of the tool section  14  is opened to a dimension which permits entry of the grip  2  into the tool. In accord with the embodiment shown in  FIGS. 4A-4C , for which the first stop  40  is a threaded cap  50 , the cap is removed from the tool  10  to expose the opening  30  and make the effective diameter for entry of the grip equal to the inside diameter ID 14  of the section  14 . In accord with the second embodiment shown in  FIGS. 5 , for which the first stop is the two piece end cap  70  attached to the end  26  of the section  14 , the ring halves  72  and  74  are positioned in an open configuration to expose the opening  30  and make the effective diameter for entry of the grip equal to the inside diameter ID 14  of the section  14 . The grip  2  is then slid through the opening  30  and into the tool sections  14  and  16  until it reaches the second stop  46 . 
         [0058]    Next, in the method for adjusting the grip, the end  26  of the tool is closed, e.g., partially blocked, with the first stop  40 , either by threading the cap  50  on to the end  26  of the section  14  or by closing the two piece end cap  70  by configuring the two ring halves  72  and  74  in a closed configuration. In accord with the embodiments comprising a two piece end cap, ring halves are secured in the closed configuration by inserting the locking pins  90  through each ring half and into the wall  18  of the section  14  so that the ring halves cannot rotate about the hinges  80 . With the stop  40  so secured at the end  26  of the tool section  10 , the end of the grip  2  opposite the eye loop  3  may be manually spread to a larger radial dimension. This can assure that the outside dimension of the portion of the grip positioned against the first stop  40  is larger than the aperture  66  or  86 , i.e., so that the grip is positioned against the cap and does not pass through the aperture. 
         [0059]    To effect contraction of the grip when placed between the stops  40  and  48 , the pull cord  130  is tensioned, thereby tensioning the cord segments  114  and  116 . Consequently a pulling force is exerted against the eyelets  120 ,  122 . With both the eyelets  120 ,  122  and the pulley blocks  102 ,  104  fixed to the tool section  14 , as the pulling force increases, forces exerted via the cord segments  114 ,  116  against the pulley blocks  106 ,  108  displace the tool section  16  toward the end  26  of the tool section  14 . In the process of so displacing the tool section  16  the distance between the stops  40  and  46  decreases, thereby transferring a compressive force along the longitudinal axis of the grip  2 . As the length of the tool  10  contracts, the grip is forced into a contracted state and the radial dimension of the grip bore, B, increases. The process of contracting the grip continues until the diameter of the grip bore increases beyond the outside dimension, e.g., diameter, of the cable  4 . 
         [0060]    Once the grip bore dimension is larger than the outside dimension of the cable  4 , the cable is inserted through the aperture  66  or  86  of the first stop and into the grip bore. as is typical, the cable may be inserted substantially or entirely into the full length of the bore to assure that sufficient surface area of the grip wire mesh is in contact with the outside surface of the cable. Once the cable is inserted the tension imposed via the pull cord  130  is released and the cable is secured by the grip. 
         [0061]    In other embodiments of the invention a tool  100  may consist of a single major tubular section  114  with a first end  126  having a first stop  40 , e.g., such as described for the tool  10  where a cap  50  or  70  is attached thereto.  FIG. 11A  is a view in cross section taken along a longitudinal axis  120  of such an exemplary tool  100  having the combination of the cap  70  and collar  78 . The tubular section may be a steel pipe but other materials (e.g., Aluminum) and shapes are contemplated. In lieu of the tool  100  comprising a second tubular section extendable in and out of the first section in a telescoping manner, the first section  114  includes a displaceable stop  146 , generally of a circular shape, near the second end  134  of the first section. In one embodiment, movement of the second stop  146  may be controlled through use of tackle similar to arrangements described for the tool  10 . The second stop  146  may be displaced along the longitudinal axis  120  of the tool  100  with the aid of one or more tracks in the form of slots  150  formed in the single tubular section. The slots  150  may be positioned at ninety degree intervals about the axis  120 , in which case the second stop  134  includes four tabs  152 A,  152 B,  152 C and  152 D which extend from the circular shape for insertion into the slots  150 . See  FIGS. 11B and 11C . 
         [0062]      FIG. 11B  is a plan view of the tool  100 , taken along the longitudinal axis  120  and  FIG. 11C  is a view taken along a major surface of the stop  146 , illustrating the four tabs  152 A- 152 D. When positioned in the tube  114  the tabs extend through the slots  150  formed in the tubular section  114 . Cord segments of the rigging may be attached to portions of the tabs that extend through the slots. Attachment of the cord segments may be fixed or may be via pulley blocks attached to tabs of the second stop along the outside of the single tubular section  114 . Generally, the slots  152 A- 152 D are of a sufficient length, L, to provide a predetermined distance through which the stop  134  can be displaced in order to adjust a grip  3  which has been inserted within the tubular section  114 . The slots terminate at the second end  134  of the section  114 . A fixed or removable third end stop  160  is positioned at the second end  134  to terminate the slots. Numerous other arrangements will be apparent to those skilled in the art to form the first, second and third stops  50 ,  146  and  160  for operation of a tool according to the invention. 
         [0063]    In still other embodiments of tools according to the invention, operation may be effected with powered assistance such as electric or pneumatic devices which displace one of the stops in the direction of the other stop. For example, the tool  10  may be driven with an actuator coupled to one of the sections  14  or  16  to expand the bore of the grip  2 . In other example embodiments of powered operation, the tool may consist of a single major tubular section as shown in  FIGS. 11  with a first end  126  having a first stop  40  wherein the displaceable stop  146  is actuator driven. With reference to  FIG. 12  a tool  200  is shown in cross section along a longitudinal axis  220 . The tool  200  comprises numerous components as described for the tool  100 , wherein like components are described with like reference numbers. For the tool  200  the displaceable stop  146  may be a piston or, as shown, may be coupled to a piston  170  which is positioned within the tubular section  114  to apply a force against a grip  2  positioned between the stops  40  and  146  to reduce the grip length. Movement of the actuator piston may be controlled to limit the extent to which the actuator driven stop  146  is displaced toward the first stop  40 . The piston  170  is displaced with the force of a conventional pneumatic or hydraulic actuator  174 . In other designs the piston may be coupled to an electric actuator or other type of powered device. With such arrangements the tool  200  can be adjusted with powered assistance to reliably control the radial dimension of the grip bore to accommodate grips and cables of varied sizes. 
         [0064]    Numerous embodiments of a tool have been described which can controllably modify the length of a grip in order to place a cable therein for pulling or tensioning. The tool is useful in a wide variety of applications where is desirable to use a grip to pull or tension cables for a variety of applications. The invention may be advantageously used in applications where grips are attached to large diameter cable, e.g., on the order of about two inches or larger. Those skilled in the art will recognize that use of the tool can at times also be advantageous when attaching smaller grips to cable. The examples used to describe operation of the invention have described cable having a circular shape, a grip having a circular shaped bore and pipes having cylindrical shapes. The invention is not so limited. Numerous additional modifications to the disclosed embodiments will be apparent to those skilled in the art. Accordingly the scope of the invention is only limited by the claims which now follow.