Patent Publication Number: US-2016245449-A1

Title: Irrigation Pipe Coupling

Description:
TECHNICAL FIELD 
     The present invention relates generally to a device for coupling two pipes; more particularly to a device for coupling thin-walled pipes such as irrigation pipe; and most particularly to a device for coupling irrigation pipes in the field while requiring only the use of simple tools. 
     BACKGROUND OF THE INVENTION 
     Farmers historically have had to fight the elements in order to harvest their crops and sell them at the highest possible price. One part of the growing equation is watering the fields. This may be done by any of a number of methods including water delivery via aluminum pipes. These pipes are generally about 20 to 40 feet in length and have diameters that range from 1½ to 12 inches depending upon the application and amount of water needed. Typically, successive pipes are joined by a spigot and bell coupling with the bell housing a rubber gasket to make a water-tight joint between the two pipes. As these pipes are long and cumbersome to move, the aluminum wall of the pipe is very thin in order to make each pipe as light as possible. However, thin-walled pipes pose a significant problem as the wall of the pipe may be so thin that it is readily damaged. Indeed, damage can occur simply from ordinary use, careless handling and deployment of the pipes or even due to vehicles driving over the pipes once the pipes are lying on the ground during use in the field. 
     When damage occurs there are generally three alternatives to remedy the situation. The first is to simply discard the damaged pipe and replace it with another. While this may solve the immediate problem, this solution is wasteful and would become cost prohibitive due to the additional costs needed to purchase or rent replacement pipes. 
     A second alternative is to weld the damaged portion of the pipe. However, this requires removal of the pipe from the field so that a highly skilled welder may repair the damaged portion off site. As the aluminum wall is extremely thin, such welding is typically beyond the skill possessed by most farmers. Also, water flow will need to be paused while repairs are made, thus incurring the cost problems associated with the first alternative. 
     Lastly, a damaged pipe may be repaired by using a specialized tool known in the art as a Henry Pipe Press. The Henry Pipe Press is a hydraulic machine that runs either on electricity or gas and is designed to be operated either in a repair shop or in the field depending on the power source. The press needs to be operated by a trained individual that possesses the required skill acquired through extensive training and practice in the art of making water tight joints. Specifically, the process of making the watertight joint entails placing the ends of the pipe to be repaired into the machine and having the machine make a series of rolled grooves and outward bends and then using the hydraulic pistons on the machine to make a series of bends and rolls to join the two pipes. This procedure is laborious and difficult to perform, especially with longer pipe sections, as the two sections of the pipe must be held straight while the machine performs the work. Thus, to do this in the field is quite difficult and time consuming as the machine takes one skilled operator and two individuals to hold the opposite ends of the pipe being repaired. Moreover, repairs using the Henry Pipe Press cannot be accomplished in the field while the ground is wet or when crops are growing. 
     In view of the above, it is clear that what is needed in the art is a coupling that can be utilized by one individual in a matter of minutes without the need for specialized training, expensive equipment or transportation of the damaged pipe from the field. The coupling should be light and assemble with very few hand tools and virtually no training. 
     SUMMARY OF THE INVENTION 
     Briefly described, the present invention is directed to a coupling for joining pipe ends of opposing first and second pipes in end-to-end relation. In accordance with an aspect of the present invention, the coupling generally comprises a tubular member and a pipe retainer. The tubular member has opposing first and second ends and a sidewall of an intermediate extent thereby defining a hollow interior having a first internal diameter. The first end is adapted to receive and surround the pipe end of the first pipe while the second end is adapted to receive and surround the pipe end of the second pipe. The pipe retainer is configured to secure each respective pipe end within the tubular member. The tubular member may also include an internal annular projection wherein each of the opposing first and second pipe ends may be inserted within the tubular member until each respective tube end abuts the internal annular projection. The tubular member may further include respective first and second annular grooves located proximate respective first and second ends of the tubular member. Each annular groove may be configured to receive a respective pipe seal and the pipe seal may be comprised of an elastomeric material. The tubular member may also have a respective step portion proximate respective first and second ends of the tubular member. Each step portion may define a second internal diameter which is larger than the first internal diameter. 
     In accordance with an aspect of the present invention, the pipe retainer may comprise a first pipe clamp adapted to be releasably secured to the first pipe, a second pipe clamp adapted to be releasably secured to the second pipe, and a clamp retainer bar having opposing ends with a first bar end removably secured to the first pipe clamp and a second bar end removably secured to the second pipe clamp. Each pipe clamp may further include a flange member wherein respective bar ends are secured to respective flange members. Each bar end may also include an aperture therein wherein each bar end is secured to its respective flange member via a bolt and nut. One or both apertures may be configured as an elongated slot so as to accommodate expansion of the tubular member, the first pipe, the second pipe or any combination thereof. With this embodiment it will become apparent that different pipe materials can be used such as PVC&#39;s, high density polyethylene, low density polyethylene and all metals. Additionally, with this it will also become apparent that different fittings such as 90 degree and 45 degree offsets as well as tees and reducers can be formed as part of the tubular member. 
     In accordance with a further aspect of the present invention, the pipe retainer may comprise a plurality of threaded compressive members threadably inserted within corresponding threaded holes within the tubular member. The threaded compressive members are adapted to exert a compressional force upon the first and second pipes to releasably secure the pipes within the tubular member. The threaded compressive members may be set screws. The outer surface of the tubular member may also include a flattened portion wherein the threaded holes are located within the flattened portion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The detailed description of some embodiments of the present invention is made below with reference to the accompanying figures, wherein like numerals represent corresponding parts of the figures. 
         FIG. 1  shows a perspective view of a tubular member amenable for use within a pipe coupling in accordance with an embodiment of the present invention; 
         FIG. 2  shows an end view of the tubular member shown in  FIG. 1 ; 
         FIG. 3  is a cross sectional view of the tubular member shown in  FIG. 1 , taken generally along line  3 - 3  in  FIG. 2 ; 
         FIG. 4  is an end view of a pipe coupling according to an embodiment of the present invention; 
         FIG. 5  is a cross sectional view of the pipe coupling shown in  FIG. 4 , taken generally along line  5 - 5  in  FIG. 4 ; 
         FIG. 6  shows a perspective view of a tubular member amenable for use within an alternative pipe coupling in accordance with an embodiment of the present invention; 
         FIG. 7  shows an end view of the tubular member shown in  FIG. 6 ; and 
         FIG. 8  is a cross sectional view of the tubular member shown in  FIG. 6 , taken generally along line  8 - 8  in  FIG. 7 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     By way of example, and referring to  FIGS. 4 and 5 , an embodiment of the present invention comprises a pipe coupling  10  for joining pipe ends  12 ,  14  of opposing first and second pipes  16 ,  18 . In accordance with an aspect of the present invention, pipe coupling  10  is meant to offer a simple and efficient alternative to repairing broken or damaged irrigation pipes or pipes designed for other above ground uses employed within the field. As such, first and second pipes  16 ,  18  may include cut and de-burred ends  12 ,  14  of a previously singularly whole length of pipe. To that end, pipe coupling  10  generally includes a tubular member  20  and a pipe retainer  22  adapted to join the two cut lengths of pipe so as to remove the damaged portion and reconstitute the previously water-tight length of pipe. 
       FIGS. 1-3  are various views of tubular member  20  which may be included within pipe coupling  10 . As shown, tubular member  20  has opposing first and second ends  24 ,  26  and a sidewall  28  of an intermediate extent thereby defining a hollow interior  30  having an internal diameter W 1 . First end  24  of the tubular member is adapted to receive and surround first pipe  16  while second end  26  is adapted to receive and surround second pipe  18  (see  FIG. 5 ). In accordance with an aspect of the present invention, hollow interior  30  has a diameter W 1  that is proportioned so as to snuggly receive pipes  16 ,  18 . That is, internal diameter W 1  is selected to be slightly larger than the external diameter D 1  of pipes  16 ,  18 . Hollow interior  30  may also include a chamfered face  32  so as to aid passage of pipe  16 ,  18  into tubular member  20 . Additionally or alternatively, to further aid in insertion of pipes  16 ,  18  tubular member  20  may be configured to include a step portion  34  wherein sidewall  28  has a reduced thickness thereby creating an expanded hollow interior portion  30 A having an internal diameter W 2  being larger than internal diameter W 1 . Step portion  34  may also include a chamfered face  36  between the step and tubular member ends  24 ,  26 . 
     To prevent, or at least minimize the possibility for leakage of fluid, tubular member  20  may be further adapted to receive and house seals  38 . It should be noted that tubular member  20  is shown with only one seal in  FIG. 3  for illustrative purposes. It is envisioned that, in use, a seal  38  would be inserted proximate each end  24 ,  26  of tubular member  20  (as seen in  FIG. 5 ) to maximize sealing efficiency between the coupling and the pipes while minimizing the potential for leakage. Seal  38  may be constructed of any suitable material, such as but not limited to an elastomeric material such as a natural or synthetic rubber or a thermoplastic. Specific examples not to be limited thereto include butadiene rubber, polytetrafluoroethylene rubber and silicon rubber. Tubular member  20  may include an annular groove  40  proximate each end  24 ,  26  within which seal  38  is seated. In this manner, lateral movement of seal  38  is prevented or minimized as pipe  16 ,  18  is slidably inserted into (or removed from) tubular member  20 . Seal  38  is selected to have a thickness T 1  such that seal  38  forms a ring-shaped member having an internal diameter W 3  which is equal to or slightly smaller than internal diameter W 1  of tubular member  20  and/or external diameter D 1  of pipe  16 ,  18 . In any event, seal  38  is selected to have a thickness and internal diameter so as to create a fluid-tight seal between seal  38  and pipe  16 ,  18 . 
     Tubular member  20  may further include an internal annular projection  42  wherein, in one aspect of the invention, annular projection  42  is located approximately half way along the length of sidewall  28  so as to divide hollow interior  30  in generally equal portions. The position of annular projection  42  may vary to accommodate tees, offsets and reducers that may be formed as part of tubular member  20 . Annular projection  42  may be configured to have a thickness T 2  which is generally equal to the wall thickness of the irrigation pipe (pipes  16 ,  18 ) so as to form a hollow portion having a reduced interior diameter W 4  which is generally equal to the internal diameter D 2  of pipe  16 ,  18  (see  FIG. 5 ). In this manner, annular projection  42  provides a hard stop for pipe ends  12 ,  14  when inserting pipes  16 ,  18  within tubular member  20  while also minimizing any flow restrictions/turbulence experienced by the water or other fluid flowing within pipes  16 ,  18  and through pipe coupling  10 . 
     Returning now to  FIGS. 4 and 5 , pipe coupling  10  includes a pipe retainer  22  configured to secure pipes  16 ,  18  within tubular member  20 . Pipe retainer  22  generally includes a first pipe clamp  44 , a second pipe clamp  46  and a clamp retainer bar  48 . Pipe clamps  44 ,  46  may be substantially identical and therefore for illustrative purposes, reference will be made hereinafter only to pipe clamp  44 . Pipe clamp  44  includes a body portion  50  having a generally circular cross section which is selected to define an internal diameter substantially equal to or slightly smaller than outer diameter D 1  of pipe  16  such that, which secured under clamping pressure, lateral travel of pipe  16  within pipe clamp  44  is prevented. Pipe clamp  44  may include a pair of outwardly projecting flanges  52 ,  54  at opposing ends of the clamp body portion  50 . Clamping pressure may be generated by drawing the flanges  52 ,  54  toward one another to thereby decrease the internal diameter defined by the body portion  50  until pipe clamp  44  is secured to pipe  16  as described above. To that end, flanges  52 ,  54  may include a hole (not shown) which is adapted to allow a bolt  56  to pass therethrough. Nut  58  can then be threaded onto bolt  56  and tightened until the desired clamping pressure is generated. It should be understood by those skilled in the art that, while clamp  44  has been shown and described as a single piece pipe clamp with a bolt/nut fastener, alternative clamps and fasteners may be utilized which produce satisfactory clamping pressures when secured to pipe  16  and that such alternatives are to be considered to be incorporated within the present teachings. 
     Secured between opposing pipe clamps  44 ,  46  is clamp retainer bar  48 . Bar  48  is selected to have a length at least equal to the length of sidewall  28  of tubular member  20  and the combined width W 5  of clamps  44 ,  46 . Bar  48  includes an aperture  60  proximate each end wherein each aperture  60  is configured to coincide with the holes within flanges  52 ,  54  such that bolt  56  passes through a first flange  52  or  54 , bar  48 , and emerges out of the other of flange  52  or  54  such that nut  58  can be threaded onto bolt  56  so as to sandwich bar  48  between flanges  52  and  54 . Alternatively, bar  48  may be positioned on the outward face of either flange  52 ,  54  before passage of bolt  56  and threading of nut  58  thereto such that the apertures within the bar and the holes within each of flanges  52 ,  54  may be oriented such that bar  48 , when secured to pipe clamps  44 ,  46  rests along the outer surface of tubular member  20 . Using either orientation, clamping pressure of pipe clamp  44  on pipe  16  and pipe clamp  46  on pipe  18  prevent lateral movement of the respective pipes within the individual clamps. Securing bar  48  between the two pipe clamps  44 ,  46  prevents withdrawal of either pipe  16  or pipe  18  from tubular member  20 . In this manner, pipes  16  and  18  are secured in an end-to-end orientation within the tubular member. 
     Bar  48  may also provide additional support to tubular member  20  to minimize (or more preferably, prevent) flexing of tubular member  20  and joined pipes  16 ,  18  so as to maintain a fluid-tight fitting between the pipe ends. The apertures within bar  48  may also be formed as elongated slots  60 A such that bar  48  is able to accommodate expansion/contraction of tubular member  20 , first pipe  16 , second pipe  18  or combinations thereof when pipe coupling  10  and pipes  16 ,  18  are deployed in the field and subject to the various temperature changes experienced during the growing season. 
     Turning now to  FIGS. 6-8 , an alternative embodiment of a pipe coupling in accordance with the present invention is generally indicated by reference number  10 ′. Pipe coupling  10 ′ is adapted to join pipe ends  12 ,  14  of opposing first and second pipes  16 ,  18  within a tubular member  20 ′ similar to that described above with regard to embodiment 10 shown in  FIGS. 1-5 . Similar to tubular member  20 , tubular member  20 ′ has opposing first and second ends  24 ′,  26 ′ and a sidewall  28 ′ of an intermediate extent thereby defining a hollow interior  30 ′ with the first end  24 ′ being adapted to receive and surround first pipe  16  and second end  26 ′ being adapted to receive and surround second pipe  18 . Unlike tubular member  20 , tubular member  20 ′ has a figured outer surface of sidewall  28 ′ wherein sidewall  28 ′ includes one or more flattened surfaces  29 ′. The internal surface of tubular member  20 ′ may be substantially identical to that of tubular member  20  and may include such features as seals  38 , annular groove  40  and annular projection  42 . 
     Coupling  10 ′ includes a pipe retainer  22 ′ in the form of a threaded compressive member  44 ′, such as a set screw, adapted to be threadably inserted within corresponding threaded hole  46 ′ within sidewall  28 ′ of tubular member  20 ′. Set screw  44 ′ is threaded within hole  46 ′ until the screw impacts pipe  16 ,  68  to thereby generate a compressional force upon the pipe  16 ,  18  to thereby prevent lateral movement of the pipe  16 ,  18  within tubular member  20 ′. Any number of set screws  44 ′ may be used so long as these screws generate the requisite compressional force needed to prevent unwanted movement of pipe  16 ,  68  within tubular member  20 ′. It should be understood by those skilled in the art that, while described as a set screw, compressive member  44 ′ may be any suitable device such as, but not limited to, a thumb screw, a machine screw, a bolt, a pipe nipple or the like. Compressive member  44 ′ may also be a pipe nipple. Similarly, while sidewall  28 ′ is shown and described as having flattened surfaces  29 ′, those skilled in the art should recognize that a tubular member having cylindrical sidewalls similar to those shown in  FIGS. 1-5  with regard to embodiment 10 may include threaded holes  46 ′ so as to receive respective compressive members  44 ′ as described above. 
     Persons of ordinary skill in the art may appreciate that numerous design configurations may be possible to enjoy the functional benefits of the inventive systems. Thus, given the wide variety of configurations and arrangements of embodiments of the present invention the scope of the present invention is reflected by the breadth of the claims below rather than narrowed by the embodiments described above.