Patent Publication Number: US-2004055084-A1

Title: Method and apparatus for sealing a bathtub overflow port for testing purposes

Description:
CROSS REFERENCE TO RELATED APPLICATION  
     [0001] This application is a continuation-in-part of U.S. Ser. No. 10/247,247 filed Sep. 19, 2002. 
    
    
     
       BACKGROUND OF THE INVENTION  
       [0002] In new building construction, the plumbers prefer not to put the finished closure valves in the bottom of tubs, or the finished decorative plate over the overflow outlet at the end of the tub until the project is finished because these elements will be often damaged as the construction project is brought to a close. Further, the piping for both of the outlets need to be checked for leaks before the inspection process is completed. The test involves running water down the vent for the drain until it reaches a level above the tub and the tester then determines whether any of the piping leaks. Thus, when the testing operation arrives, a plug is put in the bottom drain of the tub and some sort of a seal plate is placed at the end of the tub on the overflow outlet.  
       [0003] Existing overflow plates have a center opening therein. There are either two or four small screw holes in the plate adjacent the center opening wherein two of the holes are used to hold the plate to the plumbing fixture. In some cases there is a fitting so that the screw hole is located directly in the middle of the access hole. In that case, that hole is in the way when the testing procedure is implemented. In any event, the testing procedure usually involves stuffing a balloon through the large center opening into the pipe in the wall and the pipe is sealed when the balloon is inflated. Further, existing seal plates normally have to be removed when the decorative plate is put on. The decorative plate is typically held by two screws which either use the screw openings of the plate or two additional openings in the case that four holes are provided.  
       [0004] Some efforts have been made to seal the overflow ports of bathtubs with a diaphragm, and then cut the diaphragm when the test is completed. (See U.S. Pat. No. 5,890,241). However, the system for including the diaphragm sometimes involves screws and tools, and is not always convenient to install or to remove after testing.  
       [0005] It is therefore a principal object of this invention to provide a seal for a bathtub overflow port that is very easy to install for testing purposes, and is easily made operable for overflow purposes when the testing is finished.  
       [0006] A further object of the invention is to provide a seal for a bathtub overflow port that is very economical to manufacture.  
       [0007] These and other objects will be apparent to those skilled in the art.  
       SUMMARY OF THE INVENTION  
       [0008] A temporary closure means for a bathtub overflow port, comprising extending through the overflow port an expandable non-threaded plug which can be expanded to seal the overflow port during the testing of the water system, and which can be moved to a non-expandable condition for easy removal from the port after the testing has been completed. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION  
     [0009]FIG. 1 is a partial perspective view of a conventional bathtub environment utilizing the invention of this application;  
     [0010]FIG. 2 is an enlarged scale sectional view taken on line  2 - 2  of FIG. 1;  
     [0011]FIG. 3 is an exploded large scale view of the expandable plug used in this invention;  
     [0012]FIG. 4 is an exploded large scale sectional view of an open overflow port about to receive the assembled plug of FIG. 2; and  
     [0013]FIG. 5 is a still larger scale sectional view similar to that of FIG. 4 showing the plug of FIG. 3 installed in a sealing condition in the overflow port of a bathtub. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION  
     [0014] With reference to FIGS. 1 and 2, a conventional bathroom structure  10  has a floor  12 , and a hollow wall  14  with a wall opening  16  therein. A conventional bathtub (“tub”)  18  has a base  20  which rests upon floor  12 . Sidewalls  22  extend upwardly from base  20  as does an end wall  24 . A bottom  26  dwells in spaced relation to the floor  12 .  
     [0015] A conventional drain port  28  is located in bottom  26 . A conventional overflow port  30  is located in the end wall  24  (FIG. 2). A vertical drain pipe  32  extends downwardly from drain port  28 , and overflow drain pipe  34  extends downwardly from overflow port  30 . A horizontal pipe  36  connects pipes  32  and  34 . A drain pipe  38  extends downwardly from the junction between pipes  34  and  36 .  
     [0016] A conventional vertical vent pipe  40  is located within the hollow wall  14 . Pipe  42  interconnects vent pipe  40  and the upper end of overflow drain pipe  34  (FIG. 2). Conventional water pipes  44  extend through hollow wall  40  and are connected to valve  46  which is interconnected to conventional control member  48  and faucet  50 .  
     [0017] With reference to FIGS.  3 - 5 , a conventional expandable plug  52  is shown which does not of itself comprise this invention. However, its use and application in conjunction with this invention is deemed to be novel.  
     [0018] The plug  52  is comprised of bolt  54  which includes head  56  and a threaded shank  58 . A cup shaped washer  60  has tapered side walls  60 A, a bottom  60 B and a square center aperture  60 C.  
     [0019] Similarly, a cup shaped washer  62  has tapered side walls  62 A, a bottom  62 B, a square center aperture  62 C, and a flat perimeter flange  62 D.  
     [0020] A resilient expandable washer  64  has a circular center aperture  64 A, tapered side walls  64 B, and an outer perimeter surface  66 .  
     [0021] Sealing washers  68  with center openings  70  are located adjacent the bottoms  60 B and  62 B of cup-shaped washers  60  and  62 , respectively.  
     [0022] As shown in FIG. 5, a washer  68  is positioned against bolt head  56 , and the cup shaped washers  60  and  62  are placed on bolt shank  58  with resilient washer  64  therebetween. A second sealing washer  68  is then placed on bolt shank  58  to be located between wing nut  72  and cup shaped washer  62 .  
     [0023] In its non-expanded condition of FIG. 4, resilient washer  64  is in a non-compressed condition, and the diameter of the washer  64  is equal to or less than the interior diameter of the overflow port  30  as shown in FIG. 4, thus permitting the plug  52  to be slidably moved into the interior of port  30  in the position shown in FIG. 5. While in that position, the wing nut  72  is rotated inwardly on threaded shank  58  to compress all the components of the plug  52  on shank  58  together so as to compress resilient washer  64  tightly between the cup-shaped washers  60  and  62 , thus expanding the perimeter  66  of washer  64  tightly against the interior surface of port  30  (FIG. 5). The deformation of the perimeter  66  against the interior of port  30  is shown in FIG. 5.  
     [0024] With the port  30  so sealed, the water testing procedure can be completed. When it is finished, the wing nut  72  is rotated outwardly on bolt shank  58  to decompress resilient washer  64 . The plug  52  can then be slidably removed from port  30  to permit a conventional cover to be placed on the port.  
     [0025] This invention eliminates the need for threads in port  30  to affix a seal plug therein, thus saving some costs in manufacturing. Further, the plug  52  is easily inserted into and removed from port  30 , which expedites the water testing procedure. This invention therefore achieves its stated objectives.