Patent Publication Number: US-7588224-B2

Title: Universal clamp

Description:
FIELD OF THE INVENTION 
   The present invention relates to a universal clamp assembly for receiving electrical conductors of various diameters without interchanging parts. More particularly, the invention relates to a clamp assembly having a support fitting with two arms, a threaded bolt mounted to the arms and a clamp member rotatably mounted on the bolt allowing rotation of the clamp member. A keeper is threadedly mounted on the bolt and partially received in a guide opening of the clamp. The keeper moves back and forth along the track of the bolt towards and away from a saddle portion of the clamp member. The bolt allows the saddle and keeper to swivel about the axis of the bolt for horizontal and vertical mounting of the clamp assembly. 
   BACKGROUND OF THE INVENTION 
   Conventional clamp and insulator assemblies are unable to accommodate a variety of sizes without interchanging parts. Common mechanical clamps used in conjunction with insulators as a multi-piece system present a number of problems, including wasting time and material. Another issue is the difficulty of performing line maintenance with separate insulators and clamps because the use of removable bolts and washers increases the chances of a lineman dropping parts during installation or losing parts during storage and handling operations. 
   The requirement for different insulators for horizontal and vertical mountings leads to an increase in the number and types of clamps. Sometimes as many as three different clamp sizes may be required for securing conductors of different diameters. Typical insulator and clamp arrangements require repairs that replace both the clamps and the insulator. Using a multi-piece clamp and insulator assembly, a lineman must be extremely cautious to avoid dangerous consequences. 
   Accordingly, a need exists for providing a universal clamp mounted on a support fitting atop an insulator that can swivel about the longitudinal axis of a bolt without passing completely through the support fitting to accommodate horizontal and vertical mounting. Further, a need exists for providing a universal clamp that can accommodate more than one size conductor between a clamp member and a keeper without changing parts. 
   SUMMARY OF THE INVENTION 
   Accordingly, an object of the present invention is to provide a universal clamp assembly having a threaded keeper mounted on a bolt for moving back and forth with bolt rotation towards a clamp member having two outwardly facing ends and a saddle disposed therebetween. 
   Another object is to provide a universal clamp assembly for securing a conductor between a keeper and the saddle section of a clamp member such that conductors of various diameters can be accommodated. 
   A further object is to provide a universal clamp assembly having the clamp member mounted on a support fitting and a threaded bolt mounted to first and second arms of the support fitting allowing rotation about a longitudinal axis of the bolt and retaining the bolt against axial movement along the longitudinal axis. 
   Still another object is to provide a universal clamp with a bolt allowing the clamp to swivel about the axis of the bolt without passing completely through the support fitting. 
   Accordingly, yet another object is to provide a universal clamp for both horizontal and vertical mounting. 
   Yet another object is to provide a universal clamp having a clamp member with the two outwardly flaring and curved ends that face away from the conductor to minimize corrosion and prevent abrasion of the conductor. 
   The foregoing objects are basically attained by providing a clamp assembly having a support fitting with first and second arms and a threaded bolt mounted to the arms for rotation about a longitudinal axis of the bolt. The bolt is retained against axial movement along the longitudinal axis. A clamp member is rotatably mounted on the bolt between the arms for rotation of the clamp member relative to the support fitting about the longitudinal axis. The clamp member is restrained against axial movement relative to the support fitting and the bolt along the longitudinal axis. The clamp member includes a guide opening through which the bolt extends. A keeper is threadedly mounted on the bolt and partially received in the guide opening. The keeper slides in the guide opening along the longitudinal axis and is restrained against rotation about the longitudinal axis relative to the clamp member. The keeper is rotatable along the longitudinal axis concurrently with the clamp member. 
   As used in this application, the terms “top”, “bottom”, and “side” are intended to facilitate the description of the invention, and are not intended to limit the present invention to any particular orientation. 
   Other objects, advantages, and salient features of the present invention will become apparent from the following detailed description, which, taken in conjunction with the annexed drawings, discloses a preferred embodiment of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Referring to the drawings which form a part of this disclosure: 
       FIG. 1  is a front perspective view of the universal clamp according to an embodiment of the present invention; 
       FIG. 2  is a front perspective view of the universal clamp according to  FIG. 1  with an electrical conductor received in the clamp member and the keeper disposed in the clamping position; 
       FIG. 3  is a front perspective view of the universal clamp according to  FIGS. 1 and 2  with an electrical conductor received in the clamp member and the keeper disposed in the clamping position with a full view of the support fitting atop an insulator; 
       FIG. 4  is a front perspective view of the universal clamp according to  FIGS. 1-3  with the clamp member swiveled away from the horizontal, while clamping the conductor between the saddle and the keeper; 
       FIG. 5  is a side elevational view of the universal clamp of  FIG. 4  with the clamp member, keeper, and electrical conductor swiveled away from the horizontal axis and towards the vertical axis; 
       FIG. 6  is a side elevational view in cross section of the universal clamp taken along line  6 - 6  of  FIG. 1 ; and 
       FIG. 7  is a front perspective view of the universal clamp according to  FIG. 1  illustrating the bolt secured by a nut adjacent to the second washer. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   As seen in  FIGS. 1-3 , a universal clamp assembly  1  includes a support fitting  16  with first and second arms  24  and a threaded bolt  20  mounted to the arms  24  for rotation about a longitudinal axis of the bolt  20 . The bolt  20  is retained against axial movement along the longitudinal axis. The clamp assembly  1  further includes a clamp member  10  rotatably mounted on the bolt  20  between the arms  24  for allowing rotation of the clamp member  10  relative to the support fitting  16  about the longitudinal axis. The clamp member  10  is restrained against axial movement relative to the support fitting  16  and the bolt  20  along the longitudinal axis. The clamp member  10  includes a guide opening  34  through which the bolt  20  extends. A keeper  14  is threadedly mounted on the bolt  20  and partially received in the guide opening  34 . The keeper  14  slides in the guide opening  34  along the longitudinal axis and is restrained against rotation about the longitudinal axis relative to the clamp member  10 . The keeper  14  is rotatable along the longitudinal axis concurrently with the clamp member  10 . 
   The support fitting  16  is disposed atop an insulator  18  and crimped onto one of the insulator  18  ends. Both the support fitting  16  and the insulator  18  are of a conventional design. First and second arms  24  of the support fitting  16  branch out from the upper portion of the insulator  18  and project towards the outer first end  11  and second end  15  of the clamp member  10 . 
   The universal feature of the clamp assembly  1  to contain a variety of electrical conductors  12  having multiple diameters d 1  is captured by the variable distance d 2  between the inside surface  26  of the keeper  14  and the saddle  36  of the clamp member  10 . Both surfaces are concavely curved and oriented against the exterior walls  13  of the conductor  12 . The back and forth movement traveled by the keeper  14  between the saddle  36  and second end  15  is controlled by rotating the bolt  20 . 
   Rotating the bolt  20  increases, or decreases, the distance between the axially fixed position clamp member  10  and the adjustable position keeper  14 . As the keeper  14  moves along the longitudinal axis of the bolt  20  within the guide opening  34 , the distance between the keeper  14  and the clamp member  10  is adjusted to accommodate the electrical conductor  12  therebetween. 
   Distance d 2  is directly proportional to the diameter d 1  of the conductor  12  received therebetween. For example, as the size of the conductor  12  diameter d 1  increases so too does the distance d 2  between the keeper  14  and the saddle  36 . The distance d 2  is equivalent to the diameter of the conductor  12  or distance d 1 . 
   The clamp member  10  is substantially J-shaped having a first longitudinal end  11  and a substantially rectangular-shaped second longitudinal end  15  adjacent to first and second arms  24  with the guide opening  34  therebetween. The clamp member  10  is further defined by a concavely curved saddle  36  disposed at the first end  11  and sandwiched between contoured ends  38 . The contoured ends  38  flare outwardly and are curved to face away from the conductor  12  to provide secure clamping of the conductor  12 , while simultaneously preventing and eliminating any abrasion of the conductor  12 . 
   The clamp member  10  is restrained against axial movement along the bolt  20  by arms  24 , with the bolt extending between the first end  11  and second end  15  and through the guide opening  34  of the clamp. The guide opening  34  is the passageway for the keeper  14  along the longitudinal axis of the threaded bolt  20 . Guide opening  34  receives both the threaded bolt  20  and keeper  14 . 
   Turning now to  FIG. 6 , the size of the keeper  14  is substantially smaller than that of the clamp member  10 . The inside surface  26  of the keeper  14  is concavely curved for fitting smoothly against the conductor  12  at the side of the conductor opposite the saddle  36 . The keeper  14  includes a rectangular bottom end  28  having a threaded bore  44  receiving the threads  30  of the bolt  20 . The bottom end  28  is received in the guide opening  34  such that its sides prevent relative rotation of the clamp member  10  and the keeper  14  about the longitudinal axis of the bolt  20 . This restriction of rotation causes the keeper  14  to move along the longitudinal axis upon rotation of the bolt  20 , specifically along the threads  30  of the bolt  20  towards the saddle  36  for securing the conductor  12 . 
   Together, the connection between the support fitting  16  and the threaded bolt  20  secures the electrical conductor  12  to the clamp assembly  1  and retains the axial position of the clamp member  10  until the keeper  14  moves away from the clamp member  10 . The arrangement of the bolt  20  enables the clamp member  10  to swivel along the longitudinal axis of the bolt  20  without passing completely through the support fitting  16 . (This relationship is discussed in further detail below.). 
   Best seen in  FIG. 6 , the bolt  20  extends entirely through both arms  24  of the support fitting  16 . The end of the bolt  20  closest to the saddle  36  is defined by a hex head  40  adjacent to a washer  42  surrounding the body of the bolt  20 . Optionally, a bolt with an eye can be disposed adjacent to the washer  42  for use with a hot-stick tool. The washer  42  prevents the bolt  20  from moving too far from the first end  11  and jamming the hex head  40  into an arm  24  of the support fitting  16 . This way, the threads  30  of the bolt  20  are always engaged with the keeper  14  while having enough space between the guide opening  34  to allow for movement of the keeper  14  relative to the diameter of the conductor  12 . 
   The opposite end of the bolt  20  is secured with a second washer  45  and a pin  46  to prevent the bolt  20  from separating from the assembly. This configuration ensures that the bolt  20  is fixed against axial movement, but can be rotated with a tool inserted into an opening  48  in the pin  46 . Additionally, turning to  FIG. 7 , the bolt  20  could be secured with a nut  50  adjacent to the second washer  45 . The nut  50  is rotated over the end  52  of the bolt  20 . Specifically, a castle nut or a jam nut would be locked with a pin. Jam nuts are preferred because they are thinner than conventional nuts and consequently occupy less space. 
   As seen in  FIGS. 4 and 5 , the unique shape of the clamp member  10  and orientation of the clamp member  10  and keeper  14  to the bolt  20  atop the support fitting  16  allows for horizontal as well as vertical mounting of the clamp member  10 . The orientation of the saddle  36  and its depth allows the clamp member  10  to restrain the conductor  12  when the clamp member  10  is horizontally or vertically attached to the end-fitting  16 . This adjustability is advantageous because the clamp member  10  is universally adaptable to accommodate conductors  12  of various diameters d 1  as well as conductors  12  oriented at various angles with respect to the longitudinal axis of the insulator  18 . By rotating the clamp member  10  vertically 90° and swiveling about the bolt  20 , the conductor  12  will be vertically mounted, as seen in  FIGS. 5 and 6 . This alignment ensures the conductor  12  is retained between the saddle  36  and first end  11 , securely between the clamp member  10  and the keeper  14 . 
   In this manner, it is possible for the clamp member  10  to pivot relative to the end fitting  16  without passing entirely through the distance between the top of the end fitting  16  and the bottom of the clamp member  10 . The clamp member  10  shape prevents a total 360° revolution of the clamp member  10  and keeper  14  with the conductor  12  wedged therebetween. 
   While a particular embodiment has been chosen to illustrate the invention, it will be understood by those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention as defined in the appended claims.