Patent Publication Number: US-11648648-B2

Title: Concrete pressure wrench

Description:
BACKGROUND OF DISCLOSURE 
     The present disclosure relates to a wrench for opening and closing a clamp, such as a clamp used to join sections of pipe in a concrete dispensing system. 
     A typical concrete dispensing system includes a concrete mixer and one or more pipes that direct concrete from the concrete mixer to a site where the concrete is to be placed. On large construction sites, a plurality of pipes are joined together to direct concrete from the concrete mixer to the site where the concrete is to be placed. At a joint between the two pipes, a clamp is used to secure a first pipe to a second pipe. 
       FIG.  1    shows an exemplary embodiment of a clamp, generally indicated at  10 , that is used to join two sections of pipe for delivering concrete to a site. The clamp  10  includes a first clamshell portion  12  and a second clamshell portion  14  that are joined at a first pin  16  and are capable of being tightened together around the joint of a first pipe and a second pipe. In some embodiments of the clamp  10 , the first clamshell portion  12  and the second clamshell portion  14  can be biased to a closed position, such as by a spring bias. The clamp  10  includes a lever  18  that can be rotated about a second pin  20 . The lever  18  can be manipulated to rotate the second clamshell portion  14  towards the first clamshell portion. Clockwise rotation of the lever  18  about the pin  20 , indicated by arrow A in  FIG.  1   , fastens the first clamshell portion  12  and the second clamshell portion  14  of the clamp  10  onto the first pipe and the second pipe at the joint of the two pipes. Counterclockwise rotation of the lever  18  about the pin  20 , in a direction opposite arrow A in  FIG.  1   , loosens the first clamshell portion  12  and the second clamshell portion  14  of the clamp  10  with respect to the pipes so the joint of the first pipe and the second pipe may be disconnected. 
     Typically, opening and closing of such a clamp having a five-inch diameter requires two or three people to rotate the lever with a tool because the people must overcome a spring force when opening the clamp  10  and when closing the clamp  10 . 
     SUMMARY OF DISCLOSURE 
     One aspect of the disclosure is directed to a wrench for opening and closing a clamp having a lever. The wrench comprises a handle section, a leverage section, and a locking assembly. The leverage section is coupled to the handle section. The leverage section includes an engagement surface to engage the clamp and an opening formed therein. The opening is configured to receive the lever of the clamp therein. The locking assembly is coupled to the leverage section. The locking assembly is configured to releasably secure the leverage section to the lever of the clamp when the lever is received within the opening of the leverage section. 
     In some embodiments, the handle section includes an upper portion and a lower portion. In some embodiments, the leverage section includes an upper portion secured to the upper portion of the handle section and a lower portion secured to the lower portion of the handle section, the lower portion of the leverage section having the opening that is configured to receive the lever of the clamp. In various embodiments, the lower portion of the leverage section is curved. In various embodiments, the wrench further comprises a strut having a first end and a second end each secured to the curved lower portion of the leverage section. In various embodiments, the locking means includes a threaded bolt that extends through a threaded hole in a wall of the lower portion of the leverage section so that an end of the threaded bolt is configured to secure the lever between the threaded bolt and an inner surface of the leverage section. In various embodiments, the wrench further comprises a platform extending laterally from an outer surface of the leverage section. In various embodiments, the handle section is linear. 
     In some embodiments, the handle section includes an upper portion and a lower portion; the leverage section includes an upper portion secured to the upper portion of the handle section and a lower portion secured to the lower portion of the handle section, the lower portion of the leverage section having the opening that is configured to receive the lever of the clamp; and the lower portion of the leverage section is curved. In various embodiments, the handle section is linear. In various embodiments, the wrench further comprises a platform extending laterally from an outer surface of the leverage section. 
     In some embodiments, the handle section and the leverage section are welded together. 
     In some embodiments, the handle section is substantially tubular and the leverage section is substantially tubular. In various embodiments, the upper portion of the leverage section is nested in the upper portion of the handle section. 
     In some embodiments, the wrench further comprises two arms extending from the lower portion of the handle section, wherein the two arms are welded to the lower portion of the second member. 
     In some embodiments, the locking assembly includes a threaded bolt that extends through a threaded hole in a wall of the leverage section so that an end of the threaded bolt is configured to secure the lever between the threaded bolt and an inner surface of the leverage section. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures is represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. In the drawings: 
         FIG.  1    is a schematic side view of a prior art clamp for joining pipes in a concrete dispensing system; 
         FIG.  2    is a perspective view of an exemplary embodiment of a wrench according to the present disclosure; 
         FIG.  3    is a side view of the wrench of  FIG.  2   ; 
         FIG.  4    is a front view of the wrench of  FIG.  2   ; 
         FIG.  5    is a back view of the wrench of  FIG.  2   . 
         FIG.  6    is a plan view of disassembled components of the wrench of  FIG.  2   ; 
         FIG.  7    is a perspective view of the components of the wrench of  FIG.  2    partially assembled; 
         FIG.  8 A  is a cross-sectional view of the wrench operating the clamp; and 
         FIG.  8 B  is a cross-sectional view of the wrench operating the clamp. 
     
    
    
     DETAILED DESCRIPTION 
     This disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” “having,” “containing,” “involving,” and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. 
     The present disclosure provides a wrench configured for opening and closing a clamp that is used to join two pipes in the concrete dispensing system, such as the clamp  10  of  FIG.  1   . The wrench is designed to engage the lever of the clamp so that manual rotation of the wrench results in rotation of the lever of the clamp. The wrench includes a curved portion to receive the lever of the clamp, a handle to apply leverage, and a lock to ensure that the wrench does not slip off of the lever when leverage is applied to the handle. 
     Embodiments of the wrench of the present disclosure may be operated by a single user to open and close the clamp. For example, embodiments of the wrench of the present disclosure can be used by a single person to open or close the clamp to connect or disconnect pipe joints in the concrete dispensing system. 
     Embodiments of the wrench of the present disclosure can increase the efficiency of installation and removal of clamps by between 40% and 60%, in terms of the amount of time needed to open and close the clamps. 
     Embodiments of the wrench of the present disclosure limit or prevent bodily injury during operation of a five-inch diameter clamp in a commercial liquified concrete dispensing system. The safety factor is improved because the user&#39;s hands are not near the lever of the clamp, such as clamp  10  of  FIG.  1   , so the user&#39;s fingers are less likely to be pinched. In some embodiments, the user can apply foot pressure to the wrench to close the clamp. 
     In some embodiments, the wrench is configured to be secured to the lever of the clamp when the wrench is in use so the wrench will not slip off of the lever of the clamp. The user slides the wrench onto the lever and then locks the wrench onto the lever during usage. 
     In some embodiments, the wrench is at least partially hollow. In some embodiments, the wrench is made of tubing. In some embodiments, the wrench is made of electrical metal tubing. In some embodiments, the tubing is welded together for reinforcement. Hollow embodiments of the wrench of the present disclosure are lighter and easier for a user to manipulate. 
     Referring now to  FIGS.  2 - 5   , an embodiment of a wrench, generally indicated at  30 , is configured for use in opening and closing clamps that have levers that are used to join pipes to deliver mixed concrete in the concrete dispensing system. In some embodiments, wrench  30  is configured for opening and closing clamp  10 . 
     The wrench  30  has an upper end  32  and a lower end  34 . The lower end  34  of the wrench  30  is configured to engage the lever  18  on the clamp  10  ( FIG.  1   ), and the upper end  32  of the wrench  30  is configured to be gripped by a user so the user can rotate the upper end  32  relative to the lower end  34  about a pivot point  36  of the wrench  30  so the lower end  34  rotates the lever  18  of the clamp  10 . 
     The wrench  30  includes a first member, generally indicated at  40 , sometimes referred to as a handle section, and a second member, generally indicated at  42 , sometimes referred to as a leverage section, that are secured together. In some embodiments, the first member and the second member are integrally formed with one another to create a unitary member. In some embodiments, the first member  40  and the second member  42  are secured together by welds. In some embodiments, the first member  40  and the second member  42  are secured together in another way, such as by threaded fasteners, clamps, or other fastening means. 
     In some embodiments, the first member  40  and the second member  42  are formed as a single piece. In some embodiments, the single piece is at least partially hollow. In some embodiments, the single piece is substantially hollow. 
     The wrench  30  may be assembled from the component parts shown in  FIG.  6   . A partially assembled perspective view of the wrench is shown in  FIG.  7   . 
     Referring to  FIG.  7   , in the embodiment of the wrench  30 , the first member  40  extends linearly from a first end  50  of the first member  40  to a second end  52  of the first member  40 . The first member  40  includes an upper portion  54  and a lower portion  56 . 
     With reference to  FIGS.  6  and  7   , the first member  40  of the wrench  30  can be seen disassembled from the second member  42  ( FIG.  7   ) of the wrench  30 . The upper portion  54  of the first member  40  is a half-pipe portion near the first end  50  of the first member  40 . The upper portion  54  of the first member  40  has a semicircular cross-section. The upper portion  54  is configured to receive a portion of the second member  42  so the second member  42  is at least partially nested within the upper portion  54  of the first member  40 . 
     The lower portion  56  of the first member  40  is tubular and is configured to be near the second end  52  of the first member  40 . Because the lower portion  56  of the first member  40  is tubular, the lower portion  56  of the first member  40  has increased rigidity relative to the upper portion  54  of the first member  40 . 
     The second end  52  of the first member  40  includes two arms, each indicated at  58 , that are configured to extend over a portion of the second member  42  near the pivot point  36  of the wrench  30  to stabilize the second end  52  of the first member  40  with respect to the second member  42 . The two arms  58  extend longitudinally so that the second member  42  can be received between the two arms  58  and secured to the two arms  58 . In some embodiments, the arms  58  are configured to be secured to the second member  42  by one or more welds. 
     In some embodiments, the first member  40  is made from metal tubing. In some embodiments, the first member  40  is made of electrical metal tubing. In the embodiment of  FIG.  2   , the first member  40  is made from electrical metal tubing having a diameter of 1.25 inches and a length L 1  of 44.25 inches. 
     The second member  42  is configured to be secured to the first member  40 . The components of the disassembled wrench  30  are shown in the plan view of  FIG.  6   , and various components of the wrench are assembled to form the second member  42  as shown in  FIG.  7    prior to securing the second member  42  to the first member  40 . 
     The second member  42  includes a tubular member  44  having a first end  60  and a second end  62 . The first end  60  of the tubular member  44  of the second member  42  is configured to be gripped by a user. The second end  62  is configured to receive the lever  18  of the clamp  10  ( FIG.  1   ) and to be secured to the lever  18  of the clamp  10 , as described in more detail below. 
     In some embodiments, the tubular member  44  of the second member  42  is made from metal tubing. In some embodiments, the tubular member  44  of the second member  42  is made of electrical metal tubing. As shown in  FIG.  6   , the tubular member  44  is formed from a linear section of electrical metal tubing having a diameter of 1 inch and a length L 2  of 61.5 inches. 
     The linear section of electrical metal tubing is subsequently bent before assembling the second member  42  shown in  FIG.  7   . As shown in  FIG.  7   , the tubular member  44  of the second member  42  includes a linear upper portion  64 , a middle portion  66 , and a curved lower portion  68 . 
     The upper portion  64  of the tubular member  44  is a linearly extending portion of the tubular member  44 . The upper portion  64  of the tubular member  44  has an outer surface  70  that is configured to be received in the half-pipe upper portion  54  of the first member  40 . The upper portion  64  of the tubular member  44  may be secured to the upper portion  54  of the first member  40 , such as by one or more welds. 
     A handle, generally indicated at  80 , is secured to the upper portion  64  of the tubular member  44  and located near the first end  60  of the tubular member  44 . The handle  80  includes a bar  82  that extends transversely with respect to a longitudinal axis  84  of the upper portion  64  of the second member  42 . A user may grip the handle  80  to rotate the second member  42  about an axis perpendicular to the longitudinal axis  84  of the upper portion  64  of the tubular member  44 . 
     In the exemplary embodiment, the bar  82  of the handle  80  is a threaded rod that is received in holes defined in the upper portion  64  of the tubular member  44  near the first end  60  of the tubular member  44 . The threaded rod is secured to the tubular member  44  of the second member  42  by two threaded nuts  86 . In some embodiments, the nuts are 6.375 inch nuts. 
     In some embodiments, a gripping surface extends over the bar  82 . In some embodiments, the gripping surface is an ergonomic gripping surface. 
     The middle portion  66  of the tubular member  44  is a substantially linear portion that joins the upper portion  64  to the lower portion  68  of the tubular member  44  of the second member  42 . 
     As shown in  FIG.  7   , the middle portion  66  of the tubular member  44  meets the upper portion  64  of the tubular member  44  at a bend  90  in the tubular member  44 . Referring momentarily back to  FIG.  3   , the bend  90  is located a distance L 3  of 23 inches below the upper end  32  of the wrench  30 . The bend  90  in the tubular member  44  is in a first direction. In some embodiments, the bend  90  has an angle α in the range of 45 degrees to 75 degrees. In some embodiments, the angle α is in the range of 55 degrees to 65 degrees. In some embodiments, the angle α is about 60 degrees. 
     The lower portion  68  of the tubular member  44  is curved in a second direction that is opposite to the direction of the bend  90  between the upper portion  64  and the middle portion  66  of the tubular member  44 . In some embodiments, the lower portion  68  includes a segment that has a diameter of curvature of 13 inches and a central angle of 160 degrees. The curved lower portion  68  terminates at the second end  62  of the tubular member  44  so the lever  18  of the clamp  10  can be easily aligned with and received in an opening  92  of the tubular second end  62  of the tubular member  44 , as described in more detail below. 
     As shown in  FIGS.  6  and  7   , a platform  94  is secured to an outer surface of the lower portion  68  of the second member  42 , and is provided to add additional leverage to the wrench  30  when closing the clamshell portions  12 ,  14  of the clamp  10 . The platform  94  is located at a distance L 4  of 15 inches below the bend  90  in the tubular member  44 . Referring momentarily back to  FIG.  3    and to  FIG.  5   , the platform  94  is located a distance L 5  of 38 inches below the upper end  32  of the wrench  30 . As shown in  FIG.  7   , the platform  94  extends laterally from an outer surface of the lower portion  68  of the tubular member  44 . For some clamps, such as clamp  10 , the spring force of the lever  18  of the clamp  10  is sufficiently high that the user needs an additional mechanical advantage to rotate the lever  18  of the clamp  10 . For such clamps, a user can place one of their feet on an upper surface of the platform  94 . Application of the user&#39;s weight to the upper surface of the platform  94  via the user&#39;s foot facilitates rotation of the wrench  30  about the pivot point  36  of the wrench  30 . 
     In some embodiments, the platform  94  has dimensions of 3.5 inches by 1.5 inches by 0.375 inches. 
     The second member  42  of the wrench  30  further includes a strut  98  that reinforces the curved lower portion  68  of the tubular member  44 . The strut  98  improves the rigidity of the curved lower portion  68  so that the curved lower portion  68  can withstand the forces necessary to rotate the lever  18  to open or close the clamp  10 , such as when a user applies their weight to the platform  94 . As shown in  FIG.  6   , the strut  98  has a length L 6  of 14 inches. 
     As shown in  FIG.  7   , when the strut  98  is secured to the lower portion  68  of the tubular member  44 , the strut  98  spans an arc length of the curved lower portion  68  of the tubular member  44 . As shown in  FIG.  3   , a first end  100  of the strut  98  is secured to the lower portion  68  and is located at the height of the platform  94 . Referring momentarily back to  FIG.  3   , a second end  102  of the strut  98  is secured to the lower portion  68  and is located a distance L 7  of 6 inches from the front end of the wrench  30 . 
     The strut  98  may be a tubular member. In some embodiments, the strut  98  is a piece of metal tubing. In some embodiments, the strut  98  is a piece of electrical metal tubing. In the embodiment of  FIG.  6   , the strut  98  is made from electrical metal tubing having a diameter of 1.25 inches. 
     The strut  98  is configured to be secured to the lower portion  68  of the tubular member  44 . In some embodiments, the first end  100  of the strut  98  and the second end  102  of the strut  98  are welded to the lower portion  68  of the tubular member  44 . 
     A locking means, generally indicated at  106  in  FIG.  2   , is secured to the tubular member  44 . In some embodiments, the locking means  106  is configured to capture the lever  18  of the clamp  10  to prevent removal of the lever  18  of the clamp  10  ( FIG.  1   ) from the wrench  30 . The locking means  106  is configured to secure the lever  18  of the clamp  10  within the second end  62  of the tubular member. In some embodiments, when the second member  42  is assembled, the locking means  106  is configured to secure the lever  18  of the clamp  10  within the opening  92  of the curved lower portion  68  of the tubular member  44 . 
     In some embodiments, the locking means  106  is a locking assembly. The locking assembly has a reinforcing plate  110  ( FIG.  6   ) configured to be secured to the tubular member  44 , a threaded bolt  112 , a wingnut  114  at one end of the bolt  112  for turning the bolt  112 , and a position limiting nut  116  secured to an opposite end of the bolt  112 . 
     When the locking means  106  is secured to the tubular member  44  as shown in  FIG.  7   , the reinforcing plate  110  is secured to an upper surface of the lower portion  68  of the tubular member  44  and the threaded bolt  112  is received by the reinforcing plate  110  and the lower portion  68  of the tubular member  44 . The threaded bolt  112  extends through a threaded hole  108  in the wall of the lower portion  68  of the tubular member  44  so that position limiting nut  116  at the second end of the threaded bolt  112  secures the lever  18  between the position limiting nut  116  and an inner surface of the second member  42 . 
     The reinforcing plate  110  is configured to be secured to the lower portion  68  of the tubular member  44 . In particular, the reinforcing plate  110  has a curved lower surface configured to be secured to a curved upper surface of the lower portion  68  of the tubular member  44 . In some embodiments, the reinforcing plate  110  is welded to the upper surface of the lower portion  68  of the tubular member. 
     In some embodiments, the reinforcing plate  110  of  FIG.  6    has dimensions of 1.875 inches by 4.5 inches. 
     As shown in  FIG.  7   , the reinforcing plate  110  extends partially over a surface of the lower portion  68  of the tubular member  44  at the second end  62  of the tubular member  44  to help the tubular member  44  resist deformation due to rotational forces when the opening  92  of the tubular member  44  engages the lever  18  of the clamp  10  to rotate the lever  18 . The reinforcing plate  110  includes a threaded hole  118  aligned with the threaded hole defined in the lower portion  68  of the tubular member  44 . 
     The threaded bolt  112  is received in the threaded hole  118  in the reinforcing plate  110  and the threaded hole  108  in the second member  42 . A first end of the threaded bolt  112  is configured to engage the lever  18  received in the second member  42  and a second end of the threaded bolt  112  is configured to be rotated by a user to tighten or loosen the threaded bolt  112 . To secure the lever  18  within the second end  62  of the tubular member  44 , a user inserts the lever  18  into the opening  92  in the second end  62  of the tubular member  44  and tightens the threaded bolt  112  so the lever  18  is firmly secured between the first end of the threaded bolt  112  and an inner surface of the second member  42 . To release the lever  18  from the second member  42 , the user loosens the threaded bolt  112  and slides the lever  18  out of the opening  92  at the second end  62  of the tubular member  44 . 
     In some embodiments, the threaded bolt  112  is automatically adjusting. In some embodiments, the wrench  30  includes a control system and an actuator to automatically adjust the threaded bolt  112  to be tightened on or loosened from the lever  18  of the clamp  10 . 
     When the lever  18  is secured within the opening  92  of the tubular member  44 , a user can rotate the wrench  30  about the pivot point  36  of the wrench  30  to rotate the lever  18  of the clamp  10 . The user grips the handle  80  and rotates the wrench  30  about the pivot point  36 . 
     In some embodiments, the threaded bolt  112  has a length of 4 inches and a diameter of 0.375 inches. 
     In some embodiments, the wingnut  114  is welded to the threaded bolt  112 . 
     In some embodiments, the position limiting nut  116  ensures that the wrench  30  does not slip off of the lever  18  of the clamp  10 . 
     The position limiting nut  116  is secured to the first end of the threaded bolt  112 . In some embodiments, the position limiting nut  116  is secured to the first end of the threaded bolt  112  by a weld. 
     In some embodiments, the position limiting nut  116  is a nut measuring 1 inch by 0.375 inches. 
     Once the components of  FIG.  6    are assembled to form the first member  40  and the second member  42  shown in  FIG.  7   , the first member  40  and the second member  42  are secured together to form the wrench  30 . 
     The upper portion  64  of the tubular member  44  is longitudinally aligned with the upper portion  54  of the first member  40  so the convex outer surface of the upper portion  64  of the tubular member  44  is nested in the concave inner surface of the half-pipe upper portion  54  of the first member  40 . The lower portion  68  of the tubular member  44  near the second end  62  of the tubular member  44  is slid between the arms  58  located at the second end  52  of the first member  40 . 
     As shown in  FIG.  3   , the upper portion  54  of the first member  40  and the upper portion  64  of the tubular member  44  are welded together at three spaced apart locations  120 ,  122 ,  124 . In some embodiments, the welds  120 ,  122 ,  124  at each spaced apart location is one inch in length. Another weld  128  is formed between the first member  40  and the tubular member  44  of the second member  42  at the bend  90  in the tubular member  44  of the second member  42 . Two more welds  130  are formed between the lower portion  68  of the tubular member  44  of the second member  42  and the two arms  58  of the first member  40 . 
     Referring to  FIGS.  8 A and  8 B , a person can use the wrench  30  to engage the lever  18  of the clamp  10  ( FIG.  1   ) and open or close the clamp  10 . The user moves the wrench  30  towards the lever  18  of the clamp so that the opening  92  of the tubular member  44  at the lower portion  68  of the tubular member  44  slides over the lever  18  along the direction of arrow B in  FIG.  8 A . In  FIG.  8 A , the lever  18  extends through the opening  92  and is received in the tubular member  44  of the second member  42 . 
     The lever  18  is held in place within the tubular member  44  by a friction fit with the tubular member  44 . Because of the curvature of the tubular member  44 , the lever  18  is wedged within the tubular member  44 , as shown in  FIGS.  8 A and  8 B . A lower surface  132  of the lever  18  engages an engagement surface  134  and an upper surface  136  of the lever  18  engages the engagement surface  134 . In some embodiments, the user then uses the wrench  30  as described below to rotate the lever  18  without using the locking means  106  to secure the lever  18  within the tubular member  44  of the wrench  30 . In some embodiments, before using the wrench  30  to rotate the lever  18 , the user adjusts the locking means  106  so that the position limiting nut  116  engages the lever  18 . The user rotates the wingnut  114  so that the threaded bolt  112  advances downward along a direction shown by arrow C. Downward movement of the threaded bolt  112  along the direction of arrow C results in the position limiting nut  116  moving toward and engaging the lever  18  of the clamp  10 . The user advances the threaded bolt  112  until the lever  18  is firmly secured between the position limiting nut  116  and the inner surface of the tubular member  44  of the second member  42 . Once secured, the engagement surface  134  of the lower portion  68  of the tubular member  44  and the position limiting nut  116  engage the lever  18  of the clamp  10 . 
     If a user wishes to rotate the lever  18  in a counterclockwise direction to close the clamshell portions  12 ,  14  of the clamp  10 , the user may apply their weight to the platform  94  by placing one of their feet on the platform  94 . The user shifts their weight onto the foot that is placed on the platform  94  and applies their weight to the platform along arrow D. Then the user pulls the handle to cause the wrench  30  to rotate in a counterclockwise direction. Counterclockwise rotation of the wrench  30  causes the lever  18  to rotate in a counterclockwise direction as shown by arrow E in  FIG.  8 B  to close the clamp  10 . 
     If a user wishes to rotate the lever  18  in a clockwise direction to open the clamshell portions  12 ,  14  of the clamp  10 , the user may push the handle of the wrench  30  to cause the wrench  30  to rotate in a clockwise direction. Clockwise rotation of the wrench  30  causes the lever  18  to rotate in a clockwise direction, opposite to arrow E, to open the clamp  10 . 
     The user then disengages the wrench  30  from the lever  18 . For embodiments in which the user has adjusted the locking means so the position limiting nut  116  secures the lever  18  within the tubular member  44 , the user then advances the bolt  112  in a direction opposite to the direction of arrow C until the position limiting nut  116  disengages the lever  18 . The user overcomes the frictional fit of the lever  18  within the tubular member by sliding the tubular member  44  relative to the lever  18  in a direction opposite to arrow B in  FIG.  8 A   
     Having thus described several aspects of at least one embodiment of this disclosure, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and scope of the disclosure. Accordingly, the foregoing description and drawings are by way of example only.