Abstract:
A reinforced fitting and pipe is provided that has increased durability during installation and service. The fitting and pipe may be formed with reinforcement ribs along a portion of the body and an annular reinforcing ring spaced inwardly from each end of the pipe and fitting. The reinforcement ribs and annular rings increase the durability and resistance to stress of the fitting and pipe, thereby avoiding the expense and time normally required for replacement or repair of a fitting and pipe that quickly fails. The fitting and pipe may have a tapered portion to further increase the stiffness of the bell portion. The bell portion of a fitting and pipe may further have a substantially Z-shaped configuration to further increase the stiffness of the bell portion.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional No. 60/629,980, filed Nov. 23, 2004. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to a reinforced pipe or fitting. More particularly, the present invention relates to a fitting and pipe having a reinforced bell portion. Still more particularly, the present invention relates to a fitting and pipe having reinforcement ribs along a portion of the body of the fitting and pipe and annular reinforcing rings disposed proximal each end of the bell portions. The reinforced fitting and pipe has increased strength and durability during installation and service.  
       BACKGROUND OF THE INVENTION  
       [0003]     Pipe and pipe fittings are often required to be buried and run underground. For example, plastic sewer pipe is normally buried at depths varying from a few feet to, in some cases, thirty feet. During installation, depending on the site condition, soil type, and other factors, the nature of the bedding for fittings and pipe may place undue stress on the pipe and pipe fittings causing them to break. Other conditions, such heavy traffic, including trucks and tractors, driving over the area in which the pipe and pipe fittings are buried further increases the undue stress exerted on the fittings and pipe. Thus, buried pipe and fittings are subjected to various degrees of static and dynamic loads and stresses depending on the type of installation, soil and site conditions, and other factors.  
         [0004]     After fittings and pipe have been installed and are in service, they are still subjected to further undue stresses. For example, settling of the soil may place the fittings and pipe under further stress, which also causes fittings and pipe to break, thereby requiring repair or replacement. Repairing or replacing buried fittings and pipe that are in service is a difficult and time consuming task, as well as being inconvenient to those relying on the service being provided by the pipe system. Furthermore, if the fittings and pipe are buried under a roadway, that must be disturbed as well. This provides a further inconvenience to those relying on commuting over the roadway.  
         [0005]     Thus, there is a continuing need to provide an improved reinforced fitting and pipe having increased strength and durability during installation and service.  
       SUMMARY OF THE INVENTION  
       [0006]     A reinforced fitting and pipe is provided that has increased durability during installation and service. The reinforced fitting and pipe of exemplary embodiments of the present invention takes into account the possible variations of site conditions and various overstressing conditions the fitting and pipe may be subjected to during installation and its service life.  
         [0007]     In accordance with one exemplary embodiment of the present invention, a fitting and pipe is formed with reinforcement ribs along a portion of the body and an annular reinforcing ring spaced inwardly on a bell portion at each end of the fitting and pipe. Thus, the reinforcement ribs and annular rings of the present invention increase the durability and resistance to stress of the fitting and pipe, thereby avoiding the expense and time normally required for replacement or repair of fittings and pipe that quickly fail.  
         [0008]     In accordance with another exemplary embodiment of the present invention, a reinforced bell member increases the stiffness at each end of the fitting and pipe. Thus, the reinforced bell member increases the durability and resistance to stress of the fitting and pipe, thereby avoiding the expense and time normally required for replacement or repair of fittings and pipe that quickly fail.  
         [0009]     In accordance with still another exemplary embodiment of the present invention, a reinforced bell member has a substantially Z-shaped configuration to further increase stiffness of the bell member.  
         [0010]     Other objects, advantages and salient features of the invention will become apparent from the following detailed description, which, taken in conjunction with annexed drawings, discloses a preferred embodiment of the present invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     The above and other aspects, features and advantages of the present invention will be more apparent from the following detailed description taken with reference to the accompanying drawings, in which:  
         [0012]      FIG. 1  is a front elevational view of a reinforced pipe fitting according to an exemplary embodiment of the present invention;  
         [0013]      FIG. 2  is a right side elevational view of the pipe fitting of  FIG. 1 ;  
         [0014]      FIG. 3  is a left side elevational view of the pipe fitting of  FIG. 1 ;  
         [0015]      FIG. 4  is a rear elevational view of the pipe fitting of  FIG. 1 ;  
         [0016]      FIG. 5  is an elevational view in cross section along line  5 - 5  of a bell portion of the pipe fitting of  FIG. 1 ;  
         [0017]      FIG. 6  is an elevational view in cross section of a bell portion of a pipe fitting having a rounded annular ring;  
         [0018]      FIG. 7  is an elevational view in cross section of a bell portion of a pipe fitting having an annular ring with a substantially L-shaped cross-sectional configuration; and  
         [0019]      FIG. 8  is a front elevational view of a reinforced pipe according to an exemplary embodiment of the present invention. 
     
    
       [0020]     Throughout the drawings, like reference numerals will be understood to refer to like parts, components and structures.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0021]      FIGS. 1-4  show a reinforced pipe fitting  11  in accordance with exemplary embodiments of the present invention. Although  FIGS. 1-4  show a “wye” fitting, the present invention is equally applicable to any suitable fitting and pipe ( FIG. 8 ), including a “tee” fitting or an elbow. Furthermore, the present invention is suitable to any shape that has a bell portion, including, but not limited to, wyes; tee-wyes; sanitary tees; combination tees of 45 and 60 degrees; bends of 1/16, ⅛, ⅙, ¼ and ¼ long sweep; reducing wyes; reducing tees; reducing tee-wyes; double tees; double wyes; double reducing tees; double reducing wyes; crosses; bushings; and bend of 22.5, 45, 60 and 90 degrees.  
         [0022]     As shown in  FIGS. 1-4 , a reinforced fitting  11  has a first body portion  13  having an outer surface  15 , a first end  17  and a second end  19 . A first passageway  25  extends between a first opening  21  disposed at the first end  17  and a second opening  23  disposed at the second end  19 .  
         [0023]     The first body portion  13  has a central portion  14 , a first bell portion  16  and a second bell portion  18 . The majority of the central portion  13  has an outer diameter less than the outer diameter of the first and second bell portions  16  and  18 . Ends of the central portion  14  slope outwardly, as shown in  FIG. 1 , to the first and second bell portions  16  and  18 .  
         [0024]     The first and second bell portions  16  and  18  are substantially similarly configured. A first tapered portion  51  of the first bell portion  16  tapers outwardly to a first annular reinforcing ring  41 . The first tapered portion  51  is highlighted by the line  56  added to the first bell portion  16  of  FIG. 5  to  6  merely illustrate the taper of the first bell portion  16  and is not additional structure. A second tapered portion  53  of the second bell portion  18  tapers outwardly to a second annular reinforcing ring  43 . The first and second tapered portions  51  and  53  increase the thickness at each bell portion of the fitting  11 , as shown in  FIGS. 5-7 , thereby increasing the stiffness of the bell portion.  
         [0025]     The first and second end portions  83  and  85  of the first and second bell portions  16  and  18  between the first and second annular rings  41  and  43  and the first and second ends  17  and  19 , respectively, have a substantially constant outer diameter. As shown in  FIGS. 5-7 , a first lip  81  extends inwardly at the first end  17  of the fitting  11 . Although not shown, a second lip extends inwardly at the second end  19  of the fitting  11 . The first annular ring  41 , the end portion  83  of the first bell portion  16  and the first lip  81  has a substantially Z-shaped cross-sectional configuration, as illustrated by the Z  FIG. 58  added to the first bell portion  16  of  FIG. 5 , that further stiffens the first bell portion  16  of the fitting  11 . The Z  FIG. 58  of  FIG. 5  merely illustrates the substantially Z-shaped configuration as it not additional structure of the first bell portion  16 . The second annular ring  43 , the second end portion  85  of the second bell portion  18  and the second lip has a substantially Z-shaped configuration that further stiffens the second bell portion  18  of the fitting. The first and second bell portions  16  and  18  of the fitting  11  are adapted to receive spigot portions of a mating fitting or pipe. The Z-shaped configuration of the bell portion increases the strength and durability of such a joint formed between the bell and spigot portions of mating fittings.  
         [0026]     The first annular reinforcing ring  41  extends outwardly from the outer surface  15  of the first bell portion  16  of the first body portion  13 . The first annular ring  41  is spaced inwardly from the first end  17  and is proximal thereto, as shown in  FIG. 1 . The second annular reinforcing ring  43  extends outwardly from the outer surface  15  of the second bell portion  18  of the first body portion  13 . The second annular ring  43  is spaced inwardly from the second end  19  and is proximal thereto, as shown in  FIG. 1 . The first and second annular rings  41  and  43  preferably extend substantially continuously circumferentially on the first body portion  13 . The first and second annular rings  41  and  43  stiffen the first and second bell portions  16  and  18  of the fitting  11 , respectively, in the area where a mating fitting and pipe is connected.  
         [0027]     A first set of ribs  61  extend outwardly from the outer surface of the first body portion  13 , as shown in  FIGS. 1-4 , substantially parallel to a longitudinal axis  60  ( FIG. 2 ) of the first body portion  13 . Each of the axial ribs  61  of the first set of ribs is preferably equidistantly spaced around the circumference of the first body portion  13 , such as spacing four ribs 90 degrees apart. Preferably, the majority of each rib  61  of the first set of ribs extends along the central portion  14  of the first body portion  13 .  
         [0028]     A second set of ribs  71  extend outwardly from the outer surface of the first body portion  13  around the circumference of the first body portion, as shown in  FIGS. 1-4 . Preferably, the second set of ribs  71  are substantially perpendicular to the first set of ribs  61 .  
         [0029]     The fitting  11  may have a second body portion  31  extending outwardly from the first body portion  11  to a third end  33  having a third opening  35 . For a tee fitting (not shown), the second body portion  31  extends outwardly from the first body portion  13  at an angle of approximately 90 degrees. For a wye fitting, the second body portion  31  extends outwardly from the first body portion  13  at an acute angle, such as 45 degrees. A second passageway  99  is formed extending between the first passageway  25  and the third opening  35 .  
         [0030]     The second body portion  31  has a main portion  93  having a substantially constant outer diameter. A distal end (the end not connected to the first body portion) of the main portion  93  tapers outwardly to define the third bell portion  95 . The majority of the main portion  93  has an outer diameter less than the outer diameter of the third bell portion  95 . A third tapered portion  96  of the third bell portion  95  tapers outwardly to a third annular reinforcing ring  45 . The third tapered portions  96  increases the thickness of the third bell portion  95  of the second body portion  31  of the fitting  11 , as shown in  FIGS. 1-4 , thereby increasing the stiffness of the fitting inwardly of the third end  33 .  
         [0031]     Preferably, the third bell portion  95  is formed substantially similarly to the first bell portion  16 , as shown in  FIGS. 5-7 . The third end portion  97  of the third bell portion  95  between the third annular ring  45  and the third end  33  has a substantially constant outer diameter. A third lip  98  ( FIG. 1 ) extends inwardly at the third end  33  of the second body portion  31  of the fitting  11 . The third annular ring  45 , the end portion  97  of the third bell portion  95  and the third lip  98  has a substantially Z-shaped configuration that further stiffens the third bell portion  95  of the fitting  11 . The Z-shaped configuration increases the strength and durability of such a joint formed between the bell and spigot portions of mating pipes and fittings.  
         [0032]     The third annular reinforcing ring  45  extends outwardly from the outer surface of the third bell portion  95  of the second body portion  31 . The third annular ring  45  is spaced inwardly from the third end  33  and is proximal thereto, as shown in  FIGS. 1-3 . The third annular ring  45  preferably extends substantially continuously circumferentially on the first body portion  13 . The third annular ring  45  stiffens the third bell portion  95  of the pipe member  11 , respectively, in the area where a mating fitting and pipe is connected.  
         [0033]     A third set of ribs may extend outwardly from the outer surface of the second body portion  33 , as shown in  FIGS. 1-3 , substantially parallel to a longitudinal axis  70  ( FIG. 2 ) of the second body portion  31 . As shown, a single rib  91  extends substantially parallel to longitudinal axis  70  on the portion of the main portion  93  of the second body portion  31  having the largest length, as shown in  FIG. 3 .  
         [0034]     A fitting  11  having reinforcement ribs, annular reinforcing rings and substantially Z-shaped bell portions according to the exemplary embodiments of the present invention assist the fitting and pipe to counteract possible bending moments that may develop between the first and second ends  17  and  19 , as well as counteracting flattening along the longitudinal axis  60 . The second set of ribs  71  counteract direct deflection from radically oriented direction at the mid-plane.  
         [0035]     The third rib  91  on the second body portion  31  counteracts loads trying to separate the second body portion  31  from the first body portion  13 . Additionally, the third rib  91  protects the second body portion from bending due to localized loads.  
         [0036]     In the exemplary embodiment shown in  FIGS. 1-4  of a wye fitting, the first set of ribs  61  includes three ribs spaced approximately 90 degrees apart on the bottom, left and right sides of the pipe member  11 . In this exemplary embodiment, there is no fourth axial rib on the first body portion  13  of the pipe member  11  due to the presence of the second body portion  31 . In the exemplary embodiment shown in  FIG. 8 , pipe  11  has four axial ribs  61  spaced approximately 90 degrees apart along the circumference of the pipe. Although not shown, one or more annular or transverse ribs may be placed along the length of pipe  11  in the manner of rib  71  of  FIG. 4 . A majority of each axial rib  61  of the first set of ribs extends along the central portion  14  of the first body portion  13  and may terminate on the bell portion, as shown in  FIGS. 1-4 . The second set of ribs  71  includes one rib extending circumferentially around the central portion  14  starting and ending at the second body portion  31 , as shown in  FIG. 1 . The third set of ribs  91  includes one rib extending substantially parallel to the longitudinal axis  70  along the portion of the second body portion  31  having the largest length. Annular rings  41 ,  43  and  45  are spaced inwardly from and proximal to the first, second and third ends on the first, second and third bell portions  16 ,  18  and  95 , respectively. The annular rings extend substantially circumferentially around the first, second and third bell portions of the fitting  11 . First, second and third outwardly tapered portions  51 ,  53  and  96  are disposed inwardly of the first, second and third annular rings, respectively. Each bell portion of the fitting  11  has a substantially Z-shaped configuration formed by the annular ring, the outer portion and the inwardly extending lip.  
         [0037]     The annular rings may be formed to have any suitable shape, including, but not limited to, square, square with small radiuses to substantially prevent sharp corners, circular ( FIG. 6 ), T-shaped ( FIG. 7 ), and L-shaped ( FIG. 7 ). As shown in  FIG. 6 , the annular ring  41  is substantially rounded. As shown in solid lines in  FIG. 7 , the annular ring  41  has a substantially L-shaped cross-sectional configuration. As shown in dashed lines in  FIG. 7 , the annular ring  41  has a substantially T-shaped cross-sectional configuration. The width of the stem of the annular ring is identified as “X.” The width of the base of the L-shaped annular ring is identified by “P” and of the T-shaped annular ring by “Z.” The height of the base of the annular ring is identified by “Q.” Preferably, for an L-shaped annular ring, the width of the base “P” is at least approximately twice as large as the height of the base “Q” (i.e., P≧2Q). Preferably, for a T-shaped annular ring, the width of the base Z is at least approximately twice as large as the width of the stem X (i.e., Z≧2X). Preferably, for a T-shaped annular ring, the height of the base Q is at least as large as the width of the stem X (i.e., Q≧X).  
         [0038]     The fitting and pipe may be made of any material suitable for the intended use of the fitting and pipe. For example, the fitting and pipe may be made of plastic, such as such as poly(vinyl chloride), polyethylene, or the like, and may be used in sewer and pressure (potable) pipe applications. Conventional techniques, such as extrusion and injection molding, may be used to make fittings and pipe according to the exemplary embodiments of the present invention.  
         [0039]     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 may be made therein without departing from the scope of the invention as defined in the appended claims.