Abstract:
A pipe coupling apparatus adapted to allow for the connection of older, common sewer or drain pipe made of concrete, clay or the like to that of the newer style polymers such as ABS, CPCV, PVC and the like. It accomplishes this through a novel connection method that eliminates having to cut off the bell end of the older sewer or drain pipe and provides for a method of stabilizing the alignment of the two connected pipes. The apparatus incorporates a pipe coupling and a flexible polymer sleeve, and depending on the dimensions of the pipes involved, may require an optional seal ring. The assembly time is greatly reduced over the prior art methodologies and the coupled pipes are less likely to leak.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates to a pipe coupling adapted to allow for the adaptation of underground common bell and spigot sewer or drain pipe generally of the same nominal diameter (although of different actual inner and outer diameters) made of concrete, clay or the like to that of the newer style polymers such as ABS, CPCV, PVC and the like. More particularly, to a multi component apparatus that can be used to repair older, broken sewer lines of varying dimensions, and in close quarters where an air and water tight seal is required by municipal regulation. 
         [0002]    As the drainage piping under cities age, repairs or replacement of the existing clay, concrete, black iron piping is imminent. Unlike today&#39;s piping materials which are lightweight, inexpensive and made within tight dimensional tolerances, the older piping is heavy, expensive and more importantly, not subject to a standardized dimensional fabrications. While pipe sizing has been standardized for decades and is based on the internal diameter of the pipe, the internal and external dimensions of the bell ends of the pipe vary dramatically even within like material pipes. This is very problematic as the conventional repair of broken lines or replacement of line sections necessitates the removal of the bell and connection with the new pipe by butting together the old and new pipes and connecting them with a steel banded rubber sleeve, a bedding of mortar or fiber tape. This is undesirable as often there is not enough room to utilize a rubber sleeve, and it leaves the connection susceptible to misalignment. Additionally, often the removal of the bell end is not an option. Misalignment does not leave a smooth path for debris to flow down, and creates a spot where the potential for the development of blockages is high. 
         [0003]    Henceforth, a pipe coupling apparatus that allows the air and water tight pipe connection of modern polymer piping to the bell or hub end of older style concrete, clay or similar sewer piping and that aligns these pipes in a sheer proof manner, would fulfill a long felt need in the plumbing industry. This new invention utilizes and combines known and new technologies in a unique and novel configuration to overcome the aforementioned problems and accomplish this. 
       SUMMARY OF THE INVENTION 
       [0004]    The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a pipe coupling apparatus which is a transition fitting that is able to allow older style clay, concrete and iron sewage pipes to connect to the newer, (standardized dimension) polymer pipes in a manner that does not require the removal of the variable dimensioned bell end of the older style pipes and leaves a smooth bottomed flow path for the sewage traversing the piping system. In accordance with the invention, an object of the present invention is to provide an improved pipe coupling capable of a leak-proof connection with any of the conventional older style pipes in close quarters. This novel design goes against all of the conventional piping wisdom in that it has non-dimensionally mated piping (I.E. different materials, from different manufactures, from different eras, with different design specifications and tolerances) being inserted into each other rather than butted together and sealed. 
         [0005]    It is another object of this invention to provide an improved pipe coupling apparatus capable of quickly connecting older style sewer pipe with the newer style polymer pipes in a manner that forms a leak tight seal. 
         [0006]    The pipe coupling apparatus detailed herein, has many of the advantages mentioned heretofore and many novel features that result in a new pipe coupling apparatus which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art, either alone or in any combination thereof. 
         [0007]    The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation, together with further advantages and objects thereof, may best be understood by reference to the following description taken in connection with accompanying drawings wherein like reference characters refer to like elements. Other objects, features and aspects of the present invention are discussed in greater detail below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a perspective view of the bell end transition coupling; 
           [0009]      FIG. 2  is a side view of the bell end transition coupling; 
           [0010]      FIG. 3  is an end view of the bell end transition coupling; 
           [0011]      FIG. 4  is a bell end view of the bell end transition coupling; 
           [0012]      FIG. 5  is perspective view of the transition gasket; 
           [0013]      FIG. 6  is a side view of the transition gasket; 
           [0014]      FIGS. 7 and 8  are an end view of the transition gasket; 
           [0015]      FIG. 9  is a perspective view of the transition gasket spacer ring; 
           [0016]      FIG. 10  is a side view of the transition gasket spacer ring; 
           [0017]      FIGS. 11 and 12  are end views of the transition gasket spacer ring; 
           [0018]      FIG. 13  is a perspective view of the straight transition coupling; 
           [0019]      FIG. 14  is a side view of the straight transition coupling; 
           [0020]      FIGS. 15 and 16  are end views of the straight transition coupling; 
           [0021]      FIG. 17  is a cross sectional view of the straight transition coupling inserted into the bell end of a clay pipe using a transition gasket spacer ring in a transition gasket to accomplish a leakproof seal; 
           [0022]      FIG. 18  is a cross sectional view of the straight transition coupling inserted into the bell end of a clay pipe using a transition gasket to accomplish a leakproof seal; and 
           [0023]      FIG. 19  is a cross sectional view of the bell end transition coupling inserted into the bell end of a clay pipe using a transition gasket to accomplish a leakproof seal. 
       
    
    
     DETAILED DESCRIPTION 
       [0024]    The above description will enable any person skilled in the art to make and use this invention. It also sets forth the best modes for carrying out this invention. There are numerous variations and modifications thereof that will also remain readily apparent to others skilled in the art, now that the general principles of the present invention have been disclosed. There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. 
         [0025]    In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of descriptions and should not be regarded as limiting. 
         [0026]    The pipe coupling apparatus of the present invention goes against all conventional concepts of connecting pipes that are designed for leak-proof mating engagement (water tight and air tight). Such couplings are common with the repair of underground sewage/drainwater pipes where the existing system consists of old clay, cement or black iron piping must be mated to the newer polymer pipes. There were no industry standards the inner and outer diameters of the old clay, cement or black iron piping, so the traditional method of connecting the non-standardized pipe to the newer style standardized polymer pipe was to butt the connecting ends together (regardless of the profile) and fabricate a leak-proof seal over this interface. This seal may be with tape, cement/mortar, rubber sleeves or any combination thereof. The seal is also what held the two pipes aligned. 
         [0027]    The pipe coupling apparatus herein does not butt the pipes together, rather is partially inserted into the older pipes and consists of either two or three components, a rigid pipe coupling (generally fabricated of a polymer adapted for connection with conventional polymer sewage pipe), a flexible sleeve (banded on either side of the sleeve&#39;s midpoint with compression straps), and an optional seal ring to go between the outer bell of the old pipe and the flexible sleeve. When installed, this system results in a pipe aligning, sheer proof, airtight and watertight repair. The latter seal ring is utilized depending upon the particulars of the dimensions of the bell end of the pipe being connected to. Since the outer dimensions of the bells differ, the seal ring may or may not be needed. Because it is partially inserted into the older pipes the sleeve does not maintain the pipes in alignment, and a flexible sleeve may be made thinner, as it only need create a watertight seal and it is not used as a structural component of the assembly. It is to be noted that although the pipe coupling must be of a smaller cross sectional outer diameter than the cross sectional inner diameter of the older pipe, flow restriction is not an issue as the polymer pipe is much smoother on the inside and generates lower friction. As a result although the pipe diameter decreases, the resistance to flow is so much lower than that of the older style clay, black iron or cement pipe, there is an actual increase in the flow rate. 
         [0028]    Since the pipes being connected carry solids or slurried material with them, there cannot be any cross sectional elevation differences between the pipes that create an area for the collection of debris. If any debris is allowed to collect, it will only exacerbate the problem and eventually clog the pipe. Hence, the conventional theory of connecting the pipes at the ends of their faces. The present pipe coupling apparatus allows for the partial insertion of the polymer pipe into the flow line area of the bell end of the older non-standardized pipe where the ends of the pipe coupling are of different diameters and are eccentric, however the bottom of the pipe coupling has linear outer and inner surface, thereby eliminating the collection of debris when the direction of flow is from the polymer pipe coupling into the older, non-standardized pipe. 
         [0029]    There are two styles of couplings, a plain end coupling  2  as seen in  FIGS. 13-16 , and a bell end coupling  4 , as seen in  FIGS. 1-4 . Either style connects identically by the insertion of their tapered end into the bell end of an older pipe. (See  FIGS. 17-19 .) The difference is dependant on what type of fitting is on the new pipe that the coupling will mate the old pipe to. Each length of newer polymer sewer pipe has a bell end and a plain end that fits inside the bell end of another length of pipe. This design maintains a common bottom line of the connected pipes so that at no point along the section of connected pipe lengths will there be any obstructions along the bottom of the joined pipes that may obstruct the flow of sewage. Although discussed and disclosed as linear couplings in an alternate embodiment it is known that these may be fabricated in 90, 45, 22.5, 60, and 30 degree or similar fittings. 
         [0030]    Looking at both of the styles of the pipe coupling, it can be seen that the pipe couplings are each linear couplings (connecting pipes in a straight line) made up of different sized and shaped sections at either end corresponding to its method of connection with the next sequential pipe. Typically, one end of the pipe coupling will be connected to either the plain end or the bell end of a dimensionally corresponding polymer pipe length while the other end will be inserted into a clay, concrete, black iron (or the like) pipe beyond the uncut bell end. The inlet section at one end of the pipe coupling will have a round inlet end with a diameter of X units and the outlet section at the other end of the pipe coupling will have a smaller round outlet end with a diameter of less than X units, wherein the ends are eccentric, such that the inlet and outlet sections do not share a common longitudinal (linear) axis running though the midpoint of the ends. The outlet section and the inlet section always have bottom edges that are parallel (the bell end pipe coupling  4 ) or that are parallel and collinear (straight end pipe coupling  2 .) The pipe couplings are only of a uniform diameter in the inlet sections, from their inlet end to approximately one half their length (up to the approximate midpoint of the pipe couplings where the inlet section ends.) 
         [0031]    In the case of the straight pipe coupling  2 , from the approximate linear midpoint of the pipe coupling, beginning at the outlet section, it narrows in cross sectional diameter while the pipe coupling&#39;s inlet section and outlet section bottom edges share a common co-linear axis along their lengths. 
         [0032]    It is to be noted that both the straight and bell end couplings bear the same eccentric ends design where their outlet end is designed for insertion into a bell end of the older style clay, concrete or iron pipes. The pipe couplings have but one orientation, wherein their outlet section linear bottoms are parallel and adjacent to the linear bottom of the pipe they are to be coupled with and inserted into. This allows for a smooth transition for the one-way flow of sewage along the length of the assembled pipe system from the residence to the main sewer. 
         [0033]    Although not illustrated, where the graded environment of the piping system is critical, the eccentric nature of the design of the pipe coupling is replaced with an concentric design, wherein the outlet end of the pipe coupling forms a frusticonocal configuration such that the pipe coupling retains a common linear axis along its entire length. 
         [0034]    Looking at a bell end coupling  4 , as seen in  FIGS. 1-4  it can be seen that the bell end coupling  4  has a round inlet end  6  at the edge of the round cylindrical inlet section  8  of the coupling  4 . Adjacent the inlet end  6  is an internal “O” ring groove  10  for the retention of a polymer “O” ring (not illustrated) that provides a watertight seal when a straight pipe end of a matingly engageable identical section of pipe is connected therein. At the other end of the round cylindrical inlet section  8  at the approximate longitudinal center of the bell end coupling  4  is a transition section  12  that tapers down uniformly from all sides into the outlet section  14 . The outlet section  14  tapers, narrowing in diameter along its length, however its bottom linear edge  18  remains parallel with the bottom linear edge  20  of the inlet section  8 . All other linear edges taken about the rest of the outlet section  14  will not lie parallel with a similar linear edge taken about the inlet section  8 . The outlet section  14  also has a tapered outer edge  22  to ease the entry of the bell end coupling  4  into the bell end of the older style pipe. 
         [0035]    The interface between the transition section  12  and the round inlet section  8  has a circular cross section that is concentric with the circular cross section of the round inlet edge  6 , however the interface between the transition section  12  and the round outlet section  14  has a circular cross section that is eccentric with the circular cross section of the round outlet edge  16 . Similarly, the circular cross section of the round inlet edge  6  is eccentric with the circular cross section of the round outlet edge  16 . This is best reflected in  FIGS. 3 and 4 . 
         [0036]    Looking at a straight coupling  2  as seen in  FIGS. 13-16 , it can be seen that the straight coupling has a round inlet end  24  at the edge of the round cylindrical inlet section  26  of the coupling  2 . The inlet section  26  extends to the approximate midpoint of the straight coupling  2  where it interfaces with the outlet section  28 . The outlet section  28  tapers, narrowing in diameter along its length, however its bottom linear edge  30  remains colinear with the bottom linear edge  32  of the inlet section  26 . All other linear edges taken about the rest of the outlet section  28  will not lie parallel with a similar linear edge taken about the inlet section  26 . The outlet section  28  has a round outlet end  34 . 
         [0037]    Similar to the bell end coupling  4 , on the straight coupling  2  the inlet section  26  has a circular cross section that is eccentric with the circular cross section of the outlet section  28 . This is best reflected in  FIGS. 15 and 16 . 
         [0038]    In operation, the outlet sections  14  or  28  of the bell end or straight coupling are inserted beyond the bell end of the old style, non-standardized pipe a short distance, until there is a snug friction fit between the outer surface of the tapered outlet sections and the inner surface of the older pipe  40  as illustrated in  FIGS. 17-19 . As can be seen, there is a straight flow path along the bottom of the couplings  2  and  4  that lies parallel to the flow path of the bottom of the old pipe. This prevents the accumulation of any debris provided that the flow direction is from the couplings  2  and  4  and into the older pipe  40 . 
         [0039]    To ensure that there is no leakage from the engagement area there is a flexible polymer seal created. This uses one or both of a flexible sleeve  42  ( FIGS. 5-8 ) and an optional seal ring  50  ( FIGS. 9-12 ). 
         [0040]    The flexible sleeve  42  is a polymer sleeve that covers the zone of transition from the bell end of the old style pipe to the coupling&#39;s outlet section  14  or  28 . The sleeve  42  has a bell end cover  44  connected to a smaller diameter coupling cover  46  by a transition region  48  that is tapered to accommodate the difference in their respective diameters. The bell end cover  44  and the coupling cover  46  have a large groove  50  and a small groove  52  formed thereon their exterior circular peripheries. This allows for the retention of a pair of exterior gear clamps or other tightenable, size adjustable, compression means to be banded on either side of the sleeve&#39;s midpoint. The compression means are capable of drawing in the interior surface of the bell end cover  44  into a leak tight contact with the bell end of the older style pipe and capable of drawing in the interior surface of the coupling cover  46  into a leak tight contact with the outlet section  14  or  28  of the coupling  2  or  4 . The inner diameter of the coupling cover  46  is dimensionally sized slightly larger than the outer diameter of the outlet section (approximately 0.020″) so that a minimum of elastic deformation is needed before compression to a full seal is accomplished. This close tolerance sizing may or may not exist with respect to the bell end cover  44  and the bell end of the old style pipe as the old style pipe varied considerably in their dimensions. 
         [0041]    If the outer diameter of the bell end of the old style pipes is significantly smaller than the inner diameter of the bell end cover  44 , compression of the bell end cover  44  with a compression means will not accomplish a leak tight seal. In this situation an optional seal ring  50  ( FIGS. 9-12 ) is placed onto the bell end of the old style pipe and is used to take up the extra space between the outside surface of the bell end of the old style pipe and the inner face of the bell end cover  44 . The seal ring  50  is made of a flexible, stretchable polymer having an outside diameter less than the inside diameter of the bell end cover  44 . The wall thickness of the seal ring  50  will be approximately ¼ inch in the preferred embodiment although the seal ring may be fabricated with any dimensions. The seal ring  50  has an outer peripheral raised flange  52  that acts as a stop for the placement of the bell end cover  44  on top of the seal ring and gives a visual indication of the alignment of the two parts before the compression means tightens down the aligned pair onto the bell end of the old style pipe. 
         [0042]    Looking at  FIG. 17  the use of the seal ring  50  between the bell end cover section of the flexible sleeve  42  and the bell end of the old style pipe is best illustrated. 
         [0043]    Looking at  FIG. 18  the seal ring  50  is eliminated, as the outer dimension of the bell end of the older style pipe is larger than that of its counterpart in  FIG. 17 . 
         [0044]      FIG. 19  merely illustrated the substitution of a bell end coupling  4  for the straight end coupling of  FIG. 17 . 
         [0045]    As discussed herein, this novel pipe coupling apparatus allows a simple leak tight “insertion style” connection of modern polymer piping to older style non standardized pipes eliminating the need to cut the bell off of the older style pipes to accomplish the outdated industry standard “butt together” style connection. With the optional seal ring, virtually all the various different sizes of older sewer/drainage pipe can be connected in the method outlined herein. 
         [0046]    As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.