Abstract:
A method and apparatus for transferring the ends of power lines between first and second supports including a frame having a pair of independently operable hoist mechanisms which each include a tension line with an attachment element at the end thereof, with the drums being rotatable by respective ratchet mechanisms for enabling the transfer of the end of a tension line from one support location to a different support location.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This patent application claims the benefit of U.S. Provisional Patent Application No. 61/593,929 filed Feb. 2, 2012, which is incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to hoists which have particular utility in the transfer of ends of power lines between support posts, and more particularly, to an apparatus and method for transferring the ends of power lines from one support post to a different nearby support post or location of support. 
       BACKGROUND OF THE INVENTION 
       [0003]    Power lines are supported in the field by support posts, or cross arms of such support posts, at elevations of 60 feet or more above the ground. It often is necessary to transfer the ends of such power lines from one support post to another due to damage, aging, or rotting of the post material. This commonly is done by hand operated hoists operated by linemen positioned at the elevation of the power line. Typically one hoist is used whereby a hook on the end of a retractable tensioning line of the hoist, such as a strap, chain, or the like, is hooked to an eyelet of a dead end connector of the power line, and an eyelet of the hoist is coupled to a first wire clamp that is secured to the power line. The retractable tensioning line of a second hoist is connected to a newly-installed dead end connector mounted on the new support post and an eyelet of the second hoist is connected to a second wire grip mounted on the power line to be transferred. Cranking movement of a crank arm of the first hoist draws the first wire grip in a direction toward the dead end connector of the power line, relieving tension so as to enable disconnection of the power line from the existing dead end connector. Through operation of the second hoist, the disconnected end of the power line then is moved into proximity for connection to the dead end connector on the new post, while it remains in a relaxed condition by the second hoist. After reconnection of the power line to the dead end connector on the new post, the second hoist is operated in a loosening direction, leaving the power line supported in the new dead end connector, whereupon both wire grips are then disconnected from the power line. Since the power lines typically are maintained in high tension, the handling of separate hoists by a workman high on the support post can be highly cumbersome, difficult, and dangerous. 
       OBJECTS AND SUMMARY OF THE INVENTION 
       [0004]    It is an object of the present invention to provide a unitary hoist having a multiplicity of tensioning lines for moving the ends of power lines between different support locations. 
         [0005]    Another object is to provide a unitary hoist as characterized above which may be more efficiently, easily, and safely used in transferring the ends of power lines between different support locations. 
         [0006]    A further object is to provide such a hoist of the above kind which eliminates the need for a separate second hoist in the transfer of power lines between support locations. 
         [0007]    Yet another object is to provide a hoist of the foregoing type that can be used in transferring power lines between support posts while utilizing a single wire grip. 
         [0008]    Still a further object is to provide a method for more efficiently and safely transferring the ends of power lines from one support location to another. 
         [0009]    Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings, in which: 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a perspective of an illustrated multiple action hoist in accordance with the present invention usable in the transfer the end of a power line from one support location to a new support location; 
           [0011]      FIG. 2  is an enlarged perspective of the hoist shown in  FIG. 1 ; 
           [0012]      FIG. 3  is still a further enlarged perspective of the hoist shown in  FIG. 1 ; 
           [0013]      FIG. 4  is an enlarged underside perspective of the illustrated hoist; 
           [0014]      FIG. 5  is an top perspective of the illustrated hoist; 
           [0015]      FIGS. 6-9  are depictions illustrating a method of disconnecting an end of a power line at an original support location; 
           [0016]      FIG. 10  depicts the end of the power line upon disconnection from the original support location, and 
           [0017]      FIGS. 11 and 12  depict use of the hoist in moving the disconnected end of the power line to a new support location. 
       
    
    
       [0018]    While the invention is susceptible of various modifications and alternative constructions, a certain illustrative embodiment thereof has been shown in the drawings and will be described below in detail. It should be understood, however, that there is no intention to limit the invention to the specific form disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention. 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0019]    Referring now more particularly to the drawings, there is shown an illustrative multiple action hoist  10  in accordance with the invention, which is effective for efficiently transferring the end of a power line  11  from one support post to second newly-installed post in relatively closely displaced relation to the original post, or from one support position on a support post to a different support position on the post either vertically or horizontally offset from the original position. As in known in the art, the end of the power line  11  commonly is connected to a support post, or a cross arm of the support post by a dead end connector  12  of a conventional type within which the terminal end of the power line  11  is clamped. The dead end connector  12  in turn is coupled to an insulator  14 , again of a known type, which is coupled to the support post or cross arm thereof in a conventional manner, such as by a sister eye bolted to the cross arm. 
         [0020]    For transferring the end of the power line from the dead end connector  12  on the original post to a dead end connector mounted on the new support post, heretofore the lineman typically uncouple the line from the existing dead end connector and secure it to a dead end connector mounted on the new post. As indicated above, this has required two hoists which must be individually operated by a lineman, which often can be difficult and cumbersome to operate by a lineman working at a high elevation above the ground. 
         [0021]    In accordance with the invention, the hoist  10  has a unitary multi-action construction that is adapted for more efficient, safer, and easier transfer of a power line from an existing support to a new support post or support location. More particularly, the hoist  10  has a pair of independently operable hoist mechanisms  20   a , 20   b  adapted for easier operation in effecting the transfer of the end of a power line to a new support location. The hoist  10  in this case includes a frame  21  comprising a pair of hollow elongated hoist supports  22   a , 22   b  fixedly secured together by an end plate  23  bolted to a rear end of the hoist supports  22   a , 22   b  and side connectors  25 , 26  interconnecting adjacent sides of the hoist supports  22   a , 22   b.  An outwardly extending hook  27  is bolted to the connecting flange plate  23  and eyelets  28   a , 28   b  are secured in forwardly extending fashion to the opposite ends of the hoist supports  22   a , 22   b,  respectively. A central shaft  29  extends transversely through the frame supports with adjusting wheels  30   a , 30   b  fixed at opposite ends thereof. 
         [0022]    In carrying out the invention, the hoist mechanisms  20   a , 20   b  each have a respective tension line receiving drum  35   a , 35   b  supported on the transverse shaft  29  with a ratchet wheel  36   a , 36   b  on a respective outer side thereof. The respective tensioning lines  38   a , 38   b,  which may be a strap, chain, cable, rope, or the like each have a hook  39   a , 39   b  at its outer end and is secured to the respective drum  35   a , 35   b  for winding and unwinding about the drum. Each hoisting mechanism  20   a , 20   b  further includes a crank arm  40   a , 40   b  supported adjacent a respective outer side of each hoist support  22   a , 22   b  for pivotable movement about the shaft  29 . The basic construction and operation of each of the hoist mechanisms  20   a , 20   b  may be of a conventional type, such as the Series 300A Lineman&#39;s hoist sold under the tradename Little Mule® by Columbus McKinnon Corporation. A dual pawl mechanism is provided comprising pawls  41   a , 41   b  and  42   a , 42   b  having respective levers  43   a , 43   b  and  44   a , 44   b  in a known type for controlling the direction of ratchet rotation, and hence, and drum rotation, as an incident to cranking movement of the arms  40   a , 40   b.  Adjustment of the levers  43   a , 43   b  and  44   a , 44   b  in one direction causes the ratchet wheels  36   a , 36   b  to move the drums  35   a , 35   b  in a direction for drawing the tension line  38   a , 38   b  into and about the respective drum, responsive to cranking movement of the arms  40   a , 40   b  and adjustment of the levers  43   a , 44   a  and adjustment in an opposite direction causes movement of the ratchet wheels  36   a , 36   b  and drums  35   a , 35   b  to rotate in a direction for unwinding the tensioning lines  38   a , 38   b  from the respective drums. 
         [0023]    In use of the hoist  10  in accordance with the invention, when the end of the power line  11  is to be relocated from one support post, or cross arm thereof, to a closely adjacent new support post or cross arm, or from a different location on the same support post a wire clamp  50  is first positioned on the power line  11  a short distance from the end of the power line  11 , and the hook  27  of the hoist is secured to a U-hook or eyelet  51  of the wire clamp  50 . As in known in the art, pushing movement inwardly of the U-hook  51  of the wire clamp  50  opens the jaws of the wire grip for receiving the line, and movement of the U-hook  51  in an opposite direction, and under the pull of the hoist hook, secures the wire grip in engaging relation about the power line  11 . The hook  39   a  of one of the tensioning straps  38   a  can be drawn out to a position for hooking onto an eyelet of the dead end connector  12 , or alternatively, can be secured to the post at the original support position. 
         [0024]    The hook  39   b  of the tensioning line  38   b  of the other hoist mechanism  22   b  can be secured to an eyelet of a dead end connector  12  pre-mounted, together with an insulator  14 , at the new support position, either on the same support pole or on a different support pole. Again, alternatively, the tensioning line  38   b  can be secured to the support post at the new location. Using one of the crank arms  40   a,  the tensioning line  38   a  is drawn into about the drum  35   a,  drawing the wire clamp  50  and the end of the power line  11  into closer proximity to the original support for relieving the tension in the power line  11 . At the same time, the crank arm  40   b  of the other hoist mechanism  22   b  may be operated to allow the tensioning line  38   b  of that hoist mechanism  22   b  to be drawn out as necessary, as depicted in  FIGS. 6-9 . 
         [0025]    In the relieved condition, the power line  11  is disconnected from the original dead end connector  12 , and upon operation of the crank arm  40   b  of the other hoist mechanism  22   b,  the drum  35   b  can be ratcheted in to draw the disconnected end of the power line  11  into close proximity to the new support location for enabling the end of the power line to be secured to the new dead end connector  12 . In lieu of disconnecting the dead end connectors from the end of the power line  11 , it will be understood that the dead end connector  12  may be disconnected from the original insulator  14  (See  FIG. 10 ), and reconnected to the newly-installed insulator  14  at the new support position. 
         [0026]    From the foregoing, it can be seen that a unitary multi-action hoist is provided which is adapted for easier, more efficient, and safe transfer of the ends of power lines between different support locations. The unitary hoist eliminates the necessity for cumbersome handling of separate hoists, and can be more simply used to transfer the ends of power lines with a single wire clamp. It will be understood that while the hoist has been described in connection with handling of the end of a single power line, it can also be used for simultaneously handling two power lines, such as in a downed condition or the like, with considerable time saving. Moreover, while the hoist has been shown for use in transferring and handling of power lines, it will be understood that the hoist would have additional uses which require synchronized handling and movement of a multiplicity of items.