Abstract:
A drain adapter assembly for joining an overflow pipe to a side wall of a bathtub for permanently sealing the overflow pipe to the tub prior to the installation of a suitable overflow trim plate. The present assembly is capable of compressing the overflow pipe to the side wall of the tub while compressibly capturing a foam gasket, thus effectively preventing water seepage between the bathtub side wall and gasket and thereby enabling the tub to be filled above its overflow opening for suitable water testing.

Description:
[0001]    The present application claims priority from U.S. Provisional Patent application serial No. 06/117,781, filed Jan. 29, 1999, entitled “BATHTUB DRAIN ADAPTER.” 
     
    
     
       TECHNICAL FIELD OF INVENTION  
         [0002]    The present invention deals with an adapter for incorporation in a bathtub overflow for the permanent connection of the overflow assembly to the overflow outlet of the bathtub. When the overflow is secured to the bathtub with the adapter, a test plug is inserted into the overflow outlet, and a test plug is inserted into the drain outlet in the bottom of the bathtub. Likewise, all of the other drain outlets in the building, such as showers, sinks and lavatories, will be plugged to allow the entire waste system to be filled with water to the level required. At this time, water can be added to the bathtub to a point that is above the overflow, to test the permanent connection of the overflow assembly to the bathtub overflow outlet for leaks.  
         BACKGROUND OF THE INVENTION  
         [0003]    When plumbing a structure such as a house, the piping is subjected to at least two waste water tests, and inspection by a building official. The first test is done after the under floor or slab rough in is completed and requires ten feet of head pressure. A second test is required on “top out” before close in, meaning that after the plumbing vents are piped through the roof, and the bathtubs are set, the waste system must be filled to the level required and inspected for leaks by the building official before insulation, sheetrock or plaster can be installed. Changes to the building code over the years regarding test procedures for plumbing waste systems now require the vents as well as the drainage piping be tested. The current system of testing does not allow the overflow to be secured to the bathtub while it is plugged off to allow testing of the building waste system. The only way of securing the current design is by installing the overflow trim plate. The present invention alleviates the problem and allows for a leak proof overflow connection where there was no mechanical connection before.  
           [0004]    As further background, reference is made to FIG. 1 which shows, in perspective, the cutaway of a typical bathtub installation including water service lines  1  and  2  feeding hot and cold service and selector knob  15  for directing water either through tub spigot  16  or, optionally, through pipe  3  to a shower overhead outlet (not shown).  
           [0005]    To drain water from tub  10 , assembly  11  is provided including down pipe  19  and tee  19 A which in turn is fed both from tub drain assembly  17  and overflow elbow  18 .  
           [0006]    As further background, reference is made to FIG. 2 which shows, in perspective, an assembly employed by the prior art for temporarily blocking overflow elbow  18  during those water tests as described above. In use, foam gasket  9  is applied to elbow  18 . Elbow  18  is typical of such products offered by AB+A characterized by having pegs  4  symmetrically disposed upon face  26  on elbow  18  for centering foam gasket  9  thereon. Once the gasket is in place, test plug  8  having center screw  5  and wing nut  7  are applied to mating threads  6  to temporarily block elbow  18  and prevent the passage of water therethrough.  
           [0007]    Despite the seeming acceptability of the assembly shown in FIG. 2, the prior art cannot maintain water-tight integrity of the overflow assembly to the tub during testing. Specifically, once the assembly has been completed, it is the assembly trim plate (not shown) which is employed to draw elbow  18  to the inner side wall of tub  10 . It is virtually impossible to install a trim plate while test plug  8  is in place. As such, one cannot test the water integrity of a tub installation including not only inspecting the installation for leakage through elbow  18  but also between the inner wall of tub  10  and foam gasket  9 .  
           [0008]    It is thus an object of the present invention to provide a means of permanently creating a water impervious seal between an overflow pipe tub side wall in order to enable water testing of the tub plumbing during a suitable waste water test.  
           [0009]    This and further objects of the present invention will be more readily appreciated when considering the following disclosure and appended drawings.  
         SUMMARY OF THE INVENTION  
         [0010]    The present invention broadly is directed to an adapter assembly for joining an overflow pipe to the side wall of a bathtub for permanently sealing the overflow line to the tub prior to the installation of a suitable overflow trim plate. The present expedient is capable of compressing the overflow pipe elbow to the side wall of the tub while compressibly capturing a foam gasket thus effectively preventing water seepage between the bathtub side wall and gasket enabling the tub to be filled above its overflow opening for suitable water testing.  
           [0011]    In a first embodiment, the pipe elbow can be configured with a threaded length which could be threadably joined to a nut capturing the tub side wall and gasket. In a second embodiment, a standard, unmodified pipe elbow can be fit with an adapter which again can be made to threadably receive a capture nut for compressibly joining a suitable gasket with a bathtub side wall. In a second embodiment, the adapter can be solvently welded to the elbow. In each instance, once the capture nut has been tightened, an effective water-tight seal is created between the gasket and tub side wall without the need for installation of the decorative overflow plate at that time. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    [0012]FIGS. 1 and 2 represent perspective views of prior art as discussed above.  
         [0013]    [0013]FIG. 3 a  is an exploded view of one embodiment of the present invention.  
         [0014]    [0014]FIG. 3 b  depicts, in perspective, the assembly of FIG. 3 a  in use.  
         [0015]    [0015]FIGS. 4 and 5 are perspective views of two embodiments of the present invention, again, in exploded view.  
         [0016]    [0016]FIG. 6 is a side plan view of the present invention.  
         [0017]    [0017]FIG. 7 is a cross-sectional view of the assembly of FIG. 6 shown in use.  
         [0018]    [0018]FIG. 8 is a perspective view of an alternative embodiment of the present invention in exploded view.  
         [0019]    [0019]FIG. 9 is an illustrative view showing the hand operation of the alternative embodiment. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0020]    Turning first to FIG. 3 a , down pipe  19  is shown being connected to overflow elbow  20  modified to enable the practice of the present invention. In comparing elbow  20  with elbow  18  of the prior art, it is seen that threaded member  23  is shown protruding from elbow  20  within the confines of protrusions  4  emanating from elbow  20  as shown. Threads  23  can be produced by extruding elbow  20  as a single unitary plastic part or, alternatively, an insert such as shown in FIGS.  4  and  5  as element  41  can be solvent welded to element  20  as desired. In continuing the practice of the present invention, foam gasket  9  is then placed upon elbow  20  being centered by protrusions  4  located thereon. As noted in FIG. 3 b , foam gasket  9  is intended to reside on the backside of tub  30  which, in turn, is provided with an opening enabling access to threaded member  23 . Working from the inner side wall of tub  30 , capture nut  21  can then be screwed down upon threaded member  23  using threads  22  to match therewith. Alternatively, the threaded member  23  could be formed with interior threads, and the capture nut  21  with outer threads.  
         [0021]    As further noted in reference to FIG. 3 a , capture nut  21  is provided with flange  24  further optionally being configured with holes  25  enabling a suitable wire tool (not shown) to be inserted within holes  25  for increasing torque rotation of capture nut  21  to enable the capture nut to compressively draw elbow  20  to tub  10  as shown in FIG. 3 b  to, in effect, tightly draw foam gasket  9  to the side wall of tub  10  creating, for the first time, a waterproof seal prior to the attachment of the later to be installed trim plate. In completing the assembly, test plug  8  is then screwed down upon elbow  20  as shown and described with reference to FIGS. 3A and 3B.  
         [0022]    [0022]FIGS. 4 and 5 show variations to the assembly of FIGS. 3 a  and  3   b.    
         [0023]    [0023]FIGS. 4 and 5 differ only in the configuration of elbow  40  (FIG. 4) and elbow  80  (FIG. 5). The remaining elements being virtually identical between the embodiments of the two figures and thus have been numbered with like numerals.  
         [0024]    Elbow  80  shown in FIG. 5 is provided with protrusions  4  such as those shown in the previously discussed figures. Elbow of this nature are commercially available from AB+A. By contrast, elbow  40  of FIG. 4 is provided with flange  46  emanating from face  48 . Elbows of this nature are commercially available from Watco, Rapidfit, New Style AB+A (January, 1999).  
         [0025]    In operation, threaded insert  41  is provided for insertion within either elbow  40  or elbow  80 . Threaded insert  41  is shown having reduced diameter section  43  which is inserted within inner side wall  44  (FIG. 4) or  84  (FIG. 5) and the ridge created thereby acts as a natural stop for threaded insert  41 . As noted previously, threaded insert  41  can be solvent welded.  
         [0026]    Once threaded insert  41  has been applied to a suitable elbow, foam gasket  9  is placed upon the elbow and centered. As shown in FIG. 5, gasket  9  would reside upon face  26  and be centered by protrusions  4 . Similarly, gasket  9  could be placed upon elbow  40  and centered by flange  46 . As noted previously, foam gasket  9  is inserted to reside behind the side wall of tub  10  as best shown by reference to FIG. 7.  
         [0027]    Once the assembly comprising down pipe  19 , threaded insert  41  and foam gasket  9  have been installed behind the side wall of tub  10 , capture nut  21  is compressively screwed down mating screw threads  22  with threads  42  and tightened by use of a suitable wire wrench whose ends are inserted within holes  25  configured within flange  24  of capture nut  21 . In so doing, down pipe  19 , and elbows  40 - 80  are compressively drawn to the side wall of tub  10  compressing foam gasket  9  thus preventing leakage of water  60  (FIG. 7) when the tub is filled above its overflow line. To complete the assembly, test plug  8  is inserted such that threaded screw  5  is caused to mate with threaded opening  51  (FIG. 6) and tightened by the application of wing nut  7 .  
         [0028]    As noted previously, FIG. 6 shows the present invention in side plan view. In reference thereto, elbow  40 , being of a standard off the shelf configuration, is provided with face  48  and flange  46  for accepting and centering foam gasket  9  thereon. Threaded insert  41  is fit within elbow  40  at opening  52  whereby reduced cross-sectional section  43  can be solvent welded to elbow  40 . Capture nut  21  is then screwed down upon the threaded section of threaded insert  41  to draw foam gasket  9  against the inner side wall of tub  10 . Such an assembly, once in place, is shown in FIG. 7 creating a water-tight installation through the application of test plug  8  screwed down within elbow  40  by mating screw  5  within threaded opening  51  supported within elbow  40  by extruded protrusion  50 .  
         [0029]    Once water testing has been completed, test plug  8  can be removed by counter-clock rotation of wing nut  7 . Thereupon, a suitable trim plate (not shown) can be inserted against the finished surface of tub  10  without disturbing any of the remaining components as described above. In use, none of the additional elements employed to create a water-tight installation will be visible to the user in light of the decorative application of the trim plate.  
         [0030]    Another alternative embodiment of the present invention is shown in FIG. 8. FIGS. 8 and 3 a  differ only in the configuration of the capture nut. The remaining elements being virtually identical between the embodiments of the two figures and thus have been numbered with like numerals. As discussed with reference to FIG. 3 a , the capture nut  21  may optionally be configured with holes  25  enabling a suitable wire tool (not shown) to be inserted within holes  25  for increasing torque rotation of capture nut  21  to enable the capture nut to compressively draw elbow to tub  10  as shown in FIG. 3 b  to, in effect, tightly draw foam gasket  9  to the side wall of tub  10 . As shown in FIG. 8, the capture nut  100  may alternatively be configured with thumb tabs  101 ,  102  to allow for easy assembly and disassembly. As illustrated in FIG. 9, an installer can use the thumb tabs  101 ,  102  to tighten or loosen the capture nut  100 , with no special tools required. Additional thumb tabs or configurations may be added as desired.  
         [0031]    Upon reading the subject application, various alternative constructions and embodiments will become obvious to those skilled in the art. These variations are to be considered within the scope and spirit of the subject invention. The subject invention is only to be limited by the claims and their equivalence.