Abstract:
A plumbing test fitting for insertion in a plumbing drain or pressure fluid distribution system includes a body with two spaced-apart lateral ports formed thereon and opening into a central bore of the body. One of the ports is adapted for receiving a hose bib for connection to a source of test fluid and the other port is provided for withdrawing a flexible diaphragm from the interior of the body with a pull member extending through the other port. The flexible diaphragm is retained in the body during a pressure or leakage test of the plumbing system and is removed after completion of the test by tearing the diaphragm away from a supporting rim part. The flexible diaphragm is foldable to be withdrawn through the other port which may be of a diameter smaller than the normal unfolded diameter of the flexible diaphragm.

Description:
BACKGROUND OF THE INVENTION 
     In the installation and repair of various plumbing systems, it is usually necessary to pressure test the system for leaks before the system is placed in service or returned to service. In this regard, it is known to install in the plumbing system a test fitting which provides for introducing pressure water or the like into the system to pressure test the various fittings of the system for leakage. 
     Certain prior art types of test fittings are available which provide for filling and pressurizing the system upstream of the fitting using a so-called hose bib, faucet or valve connected to the fitting and connectable to a source of pressure water. Certain types of prior art fittings are also known which require relatively large and complicated structures and large ports for removing plugs, bladders or diaphragms of types which are substantially rigid or operable to be pressurized to block the plumbing system so that fluid may be introduced into the system for the leakage test. Releasing fluid to flow out of the plumbing system after the test is complete can be somewhat difficult with prior art systems and may result in the likelihood of fluid spillage before the port through which the rigid plug, diaphragm or bladder is removed can be closed. 
     Accordingly, there has been a need to provide an improved plumbing system test fitting of the general type discussed hereinabove. It is to these ends that the present invention has been developed. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention provides an improved test fitting for leakage testing of plumbing systems. In particular, the invention provides a test fitting which is inexpensive, relatively compact, is left intact as part of the plumbing system and which does not cause any restriction to fluid flow through the system nor add any substantial expense to the system. 
     In accordance with one aspect of the present invention, a plumbing system test fitting is provided which includes a body for receiving respective ends of plumbing conduits in sealed relationship therewith, the body including two spaced-apart, lateral, closable ports. One of the ports is adapted for connection to a faucet or so called hose bib for filling the plumbing system with fluid, usually water, and the other port is adapted for removal of a flexible, collapsible diaphragm which closes over a through passage or bore of the fitting and blocks the flow of fluid out of the system during leakage testing. The second port may be of relatively small diameter and is easily closeable with a small diameter threaded plug once the diaphragm has been removed. During installation of the test fitting, the diaphragm is placed within the fitting and is retained therein by a sleeve member. A generally flexible lanyard or pull member is attached at one end to the diaphragm, extends through the relatively small diameter lateral port and is preferably connected to a pull ring at its opposite end. 
     In accordance with further aspects of the present invention, several embodiments of flexible diaphragms are provided which are configured to be relatively easy to rupture when a lanyard or pull member is forcibly pulled to remove the diaphragm from the test fitting. However, the diaphragms are able to withstand substantial hydrostatic pressure to enable leakage testing of the plumbing system upstream of the fitting. Still further, the test fitting may be installed either horizontally, vertically or at any inclination needed for testing a plumbing system. 
     In accordance with yet a further aspect of the present invention, a plumbing system test fitting is provided which is configured such that, upon rupture of the flexible diaphragm and withdrawal of the diaphragm from the fitting, an insignificant amount of fluid at most is “spilled” through the lateral diaphragm exit port. 
     Those skilled in the art will further appreciate the above mentioned features and advantages of the plumbing system test fitting of the invention together with other important aspects thereof upon reading the detailed description which follows in conjunction with the drawings. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     FIG. 1 is a somewhat simplified schematic view of a typical plumbing system including the test fitting of the present invention disposed therein; 
     FIG. 2 is a longitudinal central section view of the plumbing system test fitting of the present invention; 
     FIG. 3 is a plan view of one preferred embodiment of a diaphragm for the test fitting of the present invention; 
     FIG. 4 is a section view taken along the line  4 — 4  of FIG. 3; 
     FIG. 5 is a plan view of a first alternate embodiment of a diaphragm for the test fitting of the invention; 
     FIG. 6 is a plan view of a second alternate embodiment of a diaphragm for the test fitting; 
     FIG. 7 is a plan view of a third alternate embodiment of a diaphragm for the test fitting; 
     FIG. 8 is a plan view of a fourth alternate embodiment of a diaphragm for the test fitting of the present invention; 
     FIG. 9 is a plan view of a fifth alternate embodiment of a diaphragm for the test fitting of the present invention; 
     FIG. 10 is a section view taken generally along the line  10 — 10  of FIG. 9; and 
     FIG. 11 is a detail section view similar to FIG. 10 on a larger scale. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the description which follows, like parts are marked throughout the specification and drawings with the same reference numerals, respectively. The drawing figures are not necessarily to scale and certain features may be shown in somewhat generalized or schematic form in the interest of clarity and conciseness. 
     Referring to FIG. 1, there is illustrated a plumbing system  10  including a vertically extending drain conduit section  10   a  connected to feeder or branch drain conduits  10   b  and  10   c.  A test fitting  14  in accordance with the invention is shown disposed in vertical conduit section  10   a,  but could be disposed in a horizontal orientation in conduit  10   d  also. Plumbing system  10  is disposed in a multi-story structure  12 , as shown in FIG.  1 . Test fitting  14  is typically used in drainage plumbing systems, although a test fitting in accordance with the present invention may also be utilized on pressure or supply plumbing systems to leakage test same. 
     Referring now to FIG. 2, test fitting  14  comprises an elongated, generally cylindrical tubular body  16  having a first end  16   a  and a second end  16   b.  A cylindrical bore  17  extends within body  16  and includes a first enlarged counterbore  17   a  opening to end  16   a,  a short intermediate counterbore  17   b  and a third enlarged counterbore  17   c  opening to the end  16   b.    
     A first, integral, laterally extending boss  18  is formed on body  16  spaced from a second, integral, laterally extending boss  19 . Boss  18  is provided with an internally threaded port  18   a  and boss  19  is also provided with an internally threaded port  19   a,  the ports  18   a  and  19   a  opening into the bores  17   c  and  17 , respectively, as shown in FIG. 2. A so-called hose bib or faucet  20  is threadedly connected to boss  19  and is operable to be connected to a conduit, not shown, for supplying test fluids, such as water, to the interior of the plumbing system to which the fitting  14  is connected. Faucet  20  includes a manual operating handle  22  for opening and closing a closure member, not shown, of the faucet  20 . 
     Referring further to FIG. 2, the fitting  14  includes a diaphragm assembly  24  including a generally cylindrical rim part  25 , dimensioned to be a snug fit within counterbore  17   b,  and a relatively thin, flexible, rupturable diaphragm part  26 . Referring briefly to FIGS. 3 and 4, rim part  25  is delimited by opposed cylindrical recesses  25   a  and  25   b,  see FIG. 4, whereby relatively thin circular diaphragm part  26  delimits the opposed recesses. Diaphragm assembly  24  may be suitably molded of a polymer material, such as polyethylene, polyvinylchloride, or similar polymers and providing the diaphragm  26  to be substantially flexible. 
     As shown in FIGS. 2,  3  and  4 , diaphragm  26  is connected to a pull member or lanyard  28  comprising a somewhat flexible strap-like member which may integrally joined to the diaphragm at one end  28   a,  chemically bonded thereto, or secured thereto by a mechanical fastener, not shown. In a preferred embodiment, the pull member  28  is secured to the diaphragm  26  near the juncture of the diaphragm with the rim part  25  and offset from the central axis  29  of the diaphragm assembly  24 . Axis  29  is coincident with the central axis of bores  17 ,  17   a,    17   b  and  17   c  when diaphragm assembly  24  is disposed in body  16 , as shown in FIG.  2 . The opposite end  28   b,  FIG. 2, of pull member  28  is preferably connected to a suitable pull ring  30  or other member which may be easily grasped to pull the diaphragm  26 , at will, so that the diaphragm will tear away from the rim part  25  at its juncture therewith. In this regard, the diaphragm  26  may be of sufficient thickness relative to the rim part  25  as to easily rupture at its juncture therewith. Alternatively, the diaphragm  26  may be scored or provided with suitable rupture lines or reduced wall thickness at its juncture with rim part  25 , or provided as described in conjunction with alternate embodiments herein. 
     When the diaphragm assembly  24  is placed in the counterbore  17   b,  pull member  28  and the pull ring  30  are first inserted through the bore  17   c  and then through port  18   a  to the exterior of the fitting  14  as the diaphragm assembly is placed within the bore  17   b.  The diaphragm assembly  24  is retained in the bore  17   b  by a tubular sleeve part  30  which may be secured in bore  17   c  and is provided with a radially extending port  31  aligned with the port  18   a.  The sleeve part  30  may be secured in the bore  17   c  in any suitable manner including being retained therein by the distal end  10   d ′ of conduit  10   d,  FIG. 2, which is insertable within the bore  17   c.  Conduit end  10   a ′ is also, as shown in FIG. 2, insertable in bore  17   a  and may be secured therein in any manner associated with conventional piping systems. For example, if the fitting  14  is adapted for use with polyvinylchloride (PVC) piping, the conduit ends  10   a ′ and  10   d ′ may be suitably adhesively secured to the body  16 . Alternatively, the bores  17   c  and  17   a  may be threaded for receiving correspondingly threaded pipe members comprising the conduit members  10   a  and  10   d,  as shown in FIG.  2 . 
     The test fitting  14  enjoys several advantages in the art of plumbing system test fittings. The diameter threaded port  18   a  may be made substantially smaller than the diameter of the diaphragm  26 , as well as ports provided in prior art plumbing test fittings, and is preferably disposed relatively closely adjacent to the bore  17   b  which supports the diaphragm assembly  24 . Accordingly, when the plumbing system  10  has been filled with liquid via the hose bib or faucet  20  so that liquid resides in the drainage piping  10   a,    10   b  and  10   c,  a certain hydrostatic pressure head exists at the diaphragm part  26 . The diaphragm part  26  is of sufficient strength to withstand at least a predetermined hydrostatic pressure head suitable for testing the plumbing system  10 . Once the plumbing system  10  has been tested and found suitable, or otherwise, water used for the hydrostatic test may be drained through port  19   a  and hose bib  20 . Alternatively, such water may be released to flow out of the system through conduit  10   d  by pulling firmly on the pull member  28  to rupture the diaphragm assembly  24 , tearing the diaphragm part  26  away from the rim part  25  at its juncture therewith and pulling the diaphragm out through the port  18   a.  Initially, the diaphragm part  26  will tend to tear away from the rim part  25  at the point of connection of the pull member  28  with the diaphragm, whereby as the diaphragm part is pulled downwardly and laterally, viewing FIG. 2, it will tend to cover the ports  31  and  18   a  to prevent fluid that has been released to flow through the conduit  10   d  to not splash out through the relatively small diameter port  18   a.    
     Once the fluid has drained away, the pull member  28  may be again pulled firmly to tear the diaphragm part  26  completely away from the rim  25  and out through the reduced diameter port  18   a.  Thanks to the flexibility of the diaphragm  26 , it may be easily folded or deformed, as required, to extract it through the ports  31  and  18   a  whereby the port  18   a  may then be closed with a conventional externally threaded pipe plug  33 , FIG. 2, and the plumbing system  10  is then ready for use. The hose bib  20  may be left in place or replaced by a similar plug threadedly joined to the body  16  at the port  19   a.    
     Accordingly, the configuration of the diaphragm assembly  24  and the body  16  is such that minimal spillage of test liquid occurs, if such test liquid is not drained through hose bib  20 , when the diaphragm part  26  is ruptured and pulled out of the fitting through the port  18   a.  Moreover, as previously mentioned, by providing the diaphragm assembly  24  of a molded polymer material, whereby the diaphragm  26  is relatively thin, and joined about its periphery to the rim part  25 , the diaphragm  26  exhibits sufficient strength to pressure test the plumbing system, but may also be easily torn away from rim part  25  at its juncture therewith, pulled intact out of the body  16  through the port  18   a  and discarded. The fitting  14  may, if desired, be reused by inserting a new diaphragm assembly  24  in the bore  17   b  in place of the diaphragm assembly which has been ruptured. 
     Looking now at FIG. 5, a first alternate embodiment of diaphragm assembly in accordance with the invention is illustrated and generally designated by numeral  40 . Diaphragm assembly  40  includes a peripheral rim part  42  similar to the rim part  25  and a relatively thin circular diaphragm part  44 , preferably integrally joined with the rim part in the same manner as for the diaphragm assembly  24 . FIG. 5 illustrates a connection part  45  for connecting a pull member, not shown, such as the pull member  28 , to a relatively thin diaphragm comprising opposed, generally semi-circular parts  46  and  48 . In response to a pulling effort on the connection part  45  by the aforementioned pull member, diaphragm parts  46  and  48  may be torn away from the rim  42  to form a substantial opening through a fitting in which the diaphragm assembly  40  has been installed. 
     Referring to FIG. 6, another embodiment of a diaphragm assembly for use with test fitting  14  is illustrated and generally designated by the numeral  50 . Diaphragm assembly  50  includes a relatively rigid peripheral rim part  52  and a flexible, thin, circular disc diaphragm part  54  configured in transverse section view to be similar to diaphragm  26 . However, diaphragm  54  includes a spiral score or tear line  56  extending substantially from the rim part  52  to a centrally disposed connection part  58  to which a pull member, not shown, may be attached. Connection part  58  is substantially centered along the central axis  59  of diaphragm assembly  50 . A pulling action on part  58  by the aforementioned pull member will cause separation and rupture of the diaphragm along the score line  56  to substantially remove the diaphragm  54  from the rim part  52  by a firm pulling action. The configuration of the diaphragm  54  lends itself to causing it to be reconfigured as a relatively long, thin strip as the diaphragm ruptures along the line  56  to further facilitate pulling the flexible diaphragm completely free of rim part  52  and through a lateral port in the main body of the fitting, such as the port  18   a.  In this way, the port  18  can be made even smaller than that required for extracting diaphragms, such as the diaphragms  26  and  46 ,  48 . 
     Referring to FIG. 7, a further modified diaphragm assembly  60  includes a circular rim part  62  and a flexible, thin circular disc diaphragm part  64  joined to the rim part in substantially the same manner as the arrangement of FIGS. 3 and 4. A laterally offset connection part  66  is secured to the diaphragm part  64  and a plurality of diverging score lines  67   a  through  67   h  are shown radiating from the connection part. Accordingly, with a pull member, not shown, attached to the diaphragm  64  at the connection part  66 , the diaphragm  64  will rupture when pulled at the juncture of the diaphragm with the rim  62  and also along the score or tear lines  67   a  through  67   h  to facilitate withdrawal of the diaphragm through a relatively small diameter exit port, such as the port  18   a.  In this way, the diaphragm part  64  may be made relatively thicker than the diaphragm part  26  to withstand higher pressures while also being easily foldable to be extracted from a relatively small diameter exit port. 
     Referring to FIG. 8, another embodiment of a diaphragm assembly in accordance with the invention is illustrated and generally designated by the numeral  70 . The diaphragm  70  has a peripheral rim part  72  similar to the rim  25  and a relatively thin circular disc diaphragm part  73  formed integral with the rim part  72 , and in generally the same manner as the diaphragm  24  assembly. However, the diaphragm assembly  70  includes a central connection part  76  which is substantially coincident with a central axis  29  of the diaphragm and which is also the central axis of the body  16 . The diaphragm member  73  is also sufficiently flexible when torn away from the rim part  72  to be extracted through the port  18   a.    
     Referring now to FIGS. 9 through 11, still another preferred embodiment of a diaphragm assembly in accordance with the invention is illustrated and generally designated by the numeral  80 . The diaphragm assembly  80  includes a cylindrical peripheral rim part  82  similar to the rim part  25  including opposed transverse faces  83  and  84 . The rim part  82  is integrally joined to a generally hemispherical or dome shaped diaphragm part  86  having a generally cylindrical annular disk portion  88  joined to the rim part  82  at a relatively thin cylindrical tear line  89 , see FIG. 11, and integrally joined to a generally hemispherical dome portion  90 . As shown in FIG. 9 the diaphragm assembly  80  also includes a radially offset connection part  92  for connecting the diaphragm part  86  to the lanyard or pull member  28 , for example. 
     The diaphragm assembly  80  may be fabricated of the same materials as mentioned previously for the diaphragm assembly  24 , for example, and is preferably installed in the fitting  14  in place of the diaphragm assembly  24  with the hemispherical portion  90  extending toward the conduit section  10   a  so that test fluid in the system acts on the diaphragm in such a way that the hemispherical portion  90  is stressed generally in compression. However, if there is a sufficient static pressure head to force the flexible hemispherical portion  90  to invert and face in the other direction, thereby placing the diaphragm part  86  substantially in tension, the diaphragm assembly  80  may still operate satisfactorily. In fact, the diaphragm assembly  80  may be initially installed in the fitting  14  with the hemispherical or dome shaped diaphragm part  86  facing in the opposite direction or toward the conduit  10   d,  if desired. 
     The construction and operation of the test fitting  14  is believed to be understandable to those skilled in the art based on the foregoing description. The components of the test fitting  14 , including the body  16  and the sleeve  30  may be formed of one of a variety of materials including polyvinylchloride, cast iron, steel, or other materials normally used for plumbing fittings. As mentioned previously, the diaphragm assembly  24  as well as the diaphragm assemblies  40 ,  50 ,  60 ,  70  and  80 , may be formed of molded polyethylene, polyvinylchloride or other flexible polymer material with sufficient strength to withstand the test pressures that the fitting will be subjected to, but also constructed such that the diaphragm members or parts  26 ,  46 ,  48 ,  54 ,  64 ,  73  and  86  may be easily torn away from their respective rim parts when it is desired to unblock a plumbing system in which the fitting  14  is disposed. 
     Although preferred embodiments of the present invention have been described in detail herein, those skilled in the art will recognize that various substitutions and modifications may be made without departing from the scope and spirit of the appended claims.