Abstract:
A tube joining and loop formation device that aligns and pre-positions two ends of a synthetic resin tubular work piece for insertion onto a single internal joining plug by frictional interference thereon. The joining device clamps the tubes inwardly from its free ends in independent fixtures which are then simultaneously driven towards coupling temporarily held in a movable aligned fixture for internal engagement therewith.

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     This device relates to tube fitting devices that secure tubes on fittings using movable jaw configurations in aligned relation to one another. 
     2. Description of Prior Art 
     Prior art devices of this type have been directed to hydraulic assembly fitting tools that hold fitting components to be joined to one another by imparting mechanical force. Such assembly tools can be seen for example in U.S. Pat. Nos. 4,189,817, 5,305,510, 5,483,731 and 6,430,792. 
     In U.S. Pat. No. 4,189,817 a hydraulic assembly tool for tubular fittings is disclosed having a fixed jaw and a movable jaw for a pair of fittings to be joined together. 
     U.S. Pat. No. 5,305,510 is directed to a hydraulic assembly tool that has a fixed jaw and a movable jaw with pre-positioning devices associated therewith. 
     A universal hydraulic tool can be seen in U.S. Pat. No. 5,483,731 in which a pair of jaws, fixed and movable, are provided for positioning and engaging a tube fitting onto a tube. 
     U.S. Pat. No. 6,430,792 claims a hydraulic tool with a fixed and movable jaw defining a swaging tool with wide shaped jaws. 
     SUMMARY OF THE INVENTION 
     A tube joining device for aligning, holding and transporting oppositely disposed flexible tubular ends of a tube to be joined together to form a loop by use of frictional engagement onto an internal fitting. The device of the invention pre-positions respective ends of a flexible synthetic resin tube section, engages and aligns and pneumatically clamps onto the tube ends. Secondary pneumatically cylinders draw the respective clamped tube ends to be joined to one another and engagement on the corresponding ends of an internal plug fitting selectively held until tube engagement occurs then the plug holder retracts out of the way and final tube joining thereon occurs in abutting relationship. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of the tube joining device of the invention; 
         FIG. 2  is an enlarged side elevational view of the jaw portion associated therewith; 
         FIG. 3  is an enlarged partial side elevational view thereof with a tube engaged in said lines and partly inserted in broken lines; 
         FIG. 4  is an enlarged end elevational view of a central jaw fitting retainment portion broken away for illustration; 
         FIG. 5  is an enlarged partial side elevational view showing tube ends inserted for and joining; and 
         FIG. 6  is an enlarged partial side elevational view with tube end joined. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG. 1  of the drawings, a tube joining device  10  of the invention can be seen having a support and positioning frame  11  with a central product positioning jig  12  extending therefrom. The jig  12  is an upstanding element having a first and second vertically spaced bracket extensions  13  and  14  respectively onto which a tubular product  24  shown in broken lines to be joined in selective position as will be described in greater detail hereinafter. 
     The tube joining device  10  has an upper support bracket frame  16  shown partially in dotted lines onto which a pair of movable jaw assemblies  17  and  18  are mounted. Each of the respective jaw assemblies  17  and  18  has a fixed gripping jaw  19  and a vertically aligned movable gripping jaw  20  thereon as best seen in  FIG. 2  of the drawings. The gripping jaws  20  have pneumatic drive cylinders  21  which upon activation will advance the gripping jaws  20  vertically on the assemblies as indicated by directional force arrows and broken lines in  FIG. 2  of the drawings towards the fixed jaws  19 . Each of the respective jaws  19  and  20  have tube engagement channels  22  formed therein and secondary preliminary product engagement guides  23  thereon. The preliminary product engagement guides  23  are positioned on oppositely disposed ends of the corresponding respective jaw pairs  19  and  20  for initial engagement outboard of the jaw  20  and inboard of the fixed jaws  19  as illustrated in the jaw assembly  17  in broken lines with the tubular work product  24  positioned therein. 
     Each of the jaw assemblies  17  and  18  are mounted on brackets  25  which are movable horizontally towards and away from one another by respective independent pneumatic cylinder activation assemblies  26  and  27  secured to the upper support bracket frame  16  as hereinbefore described and best seen in  FIG. 1  of the drawings. 
     A tube plug holder assembly  28  is movably secured to the upper support frame  16  for reciprocation for and aft between the respective jaw assemblies  17  and  18 . The tube plug holder assembly  28  has a pair of spaced parallel tube engagement end guide plates  29  and  30  which extend from a support fitting  31  which has a pair of resilient plug retainment clips  32 A and  32 B, best seen in  FIGS. 2 and 3  of the drawings. The tubular engagement end guide plates  29  and  30  each have a notch  33  therein inwardly of one end thereof with tapered edge surfaces  34  thereabout. The notches  33  are in aligned orientation with the hereinbefore described resilient retainment clips  32 A and  32 B and the respective closed jaw pairs  19  and  20  of the jaw assembly  17  and  18  during use. 
     The tube engagement end guide plates  29  and  30  are of sufficient longitudinal length to extend vertically beyond the plug retaining clips  32 A and  32 B to correspond with the respective jaw elements  20  when in open pre-activated position as illustrated in  FIG. 2  of the drawings. The tube plug holder assembly  28  is secured to its own pneumatic activation cylinder assembly  35 , best seen in  FIG. 4  of the drawings, for trans-lateral for and aft movement between the hereinbefore described movable jaw assemblies  17  and  18 . 
     A control activation console  36  has interdependent dual activation buttons  37  which require simultaneous depression to begin the tube joiner operational sequence as will be disclosed in greater detail hereinafter. 
     A source of pneumatic pressure is provided as well as a sequential control circuit for activation sequence of the hereinbefore described multiple piston and cylinder assemblies  21 ,  26 ,  27  and  35  to achieve the required coordinated interdependent jaw assembly activation and movement. 
     A master emergency stop button  38  is provided on the control console  36  for emergency stop required in accordance with machine operator safety protocol established within the industry as will be well known to those skilled in the art. 
     In operation, the tubular product  15  which is of a loop configuration, in this example, to be formed requires a specific length of tubular work product  24  to be joined together at its respective free ends  24 A and  24 B. The length of tubing product  24  is pre-cut to a pre-determined length which is dependent as to the desired loop size to be so formed. The tubular work product  24  in this application is preferably made of synthetic resin material of suitable walled thickness for its intended use. 
     In order to effectively join the free ends  24 A and  24 B of the tube work product  24  together, a tube joining plug  39  preferably of molded synthetic resin material is formed having a plurality of annular tapered engagement flanges  40  thereon and a central upstanding tube end engagement stop rib  41  as best seen in  FIG. 3  of the drawings. The plug  39  is manually inserted by the operator (not shown) into and held by the respective retainment clips  32 A and  32 B of the plug holder assembly  28  in longitudinal alignment with the hereinbefore described notches  33  in the tube engagement guide plates. 
     The pre-cut tubular work product  24  is then loaded into the tube joining device  10  of the invention by placing same onto the positioning jig  12  and is specifically so chosen bracket extension  13  or  14  which is determined by the diameter of loop to be formed. The respective free ends  24 A and  24 B of the tube are then placed between the jaws  19  and  20  in the respective jaw assemblies  17  and  18 . The tubular work product  24  is engaged and held in place initially by the secondary preliminary product engagement guides  23 , the bracket extension position so chosen  13  or  14  and by their respective abutting of the corresponding guide plates  29  and  30  surfaces illustrated at  29 A and  30 A respectively. 
     The operator (not shown) begins the tubular joining sequence by depressing simultaneously the hereinbefore described dual start buttons. The movable jaws  20  descend gripping the tube ends  24 A and  24 B between the so engaged jaw pairs  19  and  20  shown sequentially in  FIGS. 2-5  of the drawings. Once so gripped, the closed jaw assemblies  17  and  18  are driven horizontally towards one another by the respective hereinbefore described pneumatic cylinder assembly drives  26  and  27  forcing the respective free ends  24 A and  24 B of the tubular work product  24  partially onto the longitudinally aligned ends of the plug  39  simultaneously. Once initially engaged to a pre-determined depth, limit switches pause the pneumatic cylinders  26  and  27  and activate the pneumatic cylinder assembly  35  of the plug holder assembly  28  withdrawing same, releasing the plug  39  which is now firmly held within the respective ends of the tubular work product  24 A and  24 B as hereinbefore described. 
     Once the tube plug holder assembly  28  has cycled back, as noted, the pneumatic cylinder assemblies  26  and  27  are reactivated completing the insertion of the free tube ends  24 A and  24 B onto the plug  39  as best seen in  FIG. 6  of the drawings. 
     Respective jaws  20  are then vertically retracted by their corresponding piston and cylinder assemblies  21  releasing the tubular product  24  which is now completed into a close loop configuration and is then ejected by the re-engagement return of the tube plug holder assembly  28  from its jaw orientation with the respective jaw assemblies  17  and  18  being repositioned for the next cycle use. 
     It will be evident from the above description that the coordinated control activation sequence of the jaw assembly closure and tube  24  end insertion onto the plug  39  is achieved by independent multiple positional element input criteria indicated by the primary operator activation once the tubular work product  24  is positioned (loaded) into the tube joiner  10  of the invention as hereinbefore described. 
     It will thus be seen that a new and novel tube joining device has been illustrated and described and it will be apparent to those skilled in the art that various changes and modification may be made thereto without departing from the spirit of the invention.