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CROSS-REFERENCE TO RELATED APPLICATIONS 
   Not applicable 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not Applicable 
   REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX 
   Not Applicable 
   BACKGROUND OF THE INVENTION 
   In modern society, a bathtub is becoming more frequently a walk-in bathtub having a hinged door and having a compressible door seal closing and sealing the door in a bather entryway through a side tub wall. The bather entryway is used by a bather to enter and exit the bathtub. 
   The present invention a walk-in bathtub adjustable door latch assembly employs a novel adjustably positionable closing lever to secure and to adjustably move and adjustably pressure a hinged door into a close sealing position in a bather entryway to guard against water leakage through the bather entryway. 
   BRIEF SUMMARY OF THE INVENTION 
   An object of the present invention is to provide a walk-in bathtub adjustable door latch assembly incorporating a novel adjustably positionable closing lever to secure and to adjustably move and adjustably pressure a door into a close sealing watertight position in a bather entryway that passes through a side tub wall. 
   Another object is to provide a latch assembly having a closing lever that engages the edge of the hinged door before the door seal begins to compress and thus makes the door easier to close and secure by a bather limited to using one hand either by choice or disability. 
   A further object is to provide easy and simple adjustment of the closing lever that is integral with the structure that incorporates the lever into the door latch assembly. 
   A further object is to provide a rugged and durable latch assembly that is aesthetically pleasing to a bather. 
   The present invention incorporates a secure, uncomplicated relatively unbreakable and inexpensively produced closing lever and thereby provides an improved door latch assembly. 
   Additional and various other objects and advantages attained by the invention will become more apparent as the specification is read and the accompanying figures are reviewed. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       FIG. 1  is a perspective view of a walk-in bathtub having a hinged door; 
       FIG. 2  is a perspective partial view from above of the preferred embodiment of a walk-in bathtub adjustable door latch assembly in an intermediate position during closing and securing of a hinged door and showing an uncompressed door seal; 
       FIG. 3  is a perspective partial view from above of the preferred embodiment of a walk-in bathtub adjustable door latch assembly showing the hinged door and the latch assembly in a closed condition and showing a compressed door seal; 
       FIG. 4  is a top plan view of a base friction disc; 
       FIG. 5  is a top plan view of a slotted rotating disc; 
       FIG. 6  is a side view of a center post; 
       FIG. 7  is a top view of a slotted rotating disc assembly; 
       FIG. 8  is a cross-sectional view of the slotted rotating disc assembly as viewed in direction  8 - 8  in  FIG. 7 ; 
       FIG. 9  is a top plan view of a top friction disc; 
       FIG. 10  is a side view of a closing lever (ball end not shown); 
       FIG. 11  is an exploded perspective view of the door latch assembly of the preferred embodiment (escutcheon not shown); 
       FIG. 12  is a perspective view of the door latch assembly of the preferred embodiment (escutcheon not shown); 
       FIG. 13  is a side view of the door latch assembly showing the closing lever in a closed position showing a maximum closure position of a bowed portion of the closing lever and showing the closing lever in an alternative open position (ball end not shown); 
       FIG. 14  is a perspective partial view from above and inside the bathtub of the preferred embodiment of a walk-in bathtub adjustable door latch assembly in an open position, showing an alternative closed position (escutcheon not shown), showing an arrow A that indicates a movement arc of the closing lever, showing a dashed line B that indicates an arc of path of contact point of a middle bowed portion of the closing lever on a lever contact strike plate, and showing the hinged door ajar; and 
       FIG. 15  is a perspective partial view from above and inside the bathtub of the preferred embodiment of a walk-in bathtub adjustable door latch assembly in a closed condition (escutcheon not shown) and showing the hinged door in a closed position. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to  FIGS. 1 through 15 , the present invention is a novel walk-in bathtub adjustable door latch assembly  20 . 
     FIG. 1  shows a walk-in bathtub  2  preferably made of molded fiberglass reinforced plastic having a bathtub side wall  4 . The side wall  4  has a bather entryway  8  that allows a bather to enter and exit the bathtub  2 . An inwardly swinging entryway hinged door  10  has a hinge  11  that mounts the door in the bather entryway  8 . An entryway door seal  12  is attached along portions of the door  10  that are interstitially positioned and compressed between the door and the edges of the bather entryway  8  during closing and sealing of the door in the entryway. 
     FIG. 2  shows an inward facing door surface  14  of the hinged door  10  that faces towards the interior of the bathtub and shows a portion of the uncompressed door seal  12  interstitially between a swinging end  16  of the door (away from the hinge) and a portion of the entryway  8 .  FIG. 2 , further shows the door latch assembly  20  attached to an inward facing surface  6  of a bathtub sidewall near an inner opening side edge  18  of the entryway  8 , shows the latch assembly in an intermediate position during closing and securing of the door  10 , and shows a middle portion  74  of the latch assembly in contact with a lever contact strike plate  86 . Preferably, the strike plate  86  is made of high density polyethylene plastic and is attached to the inward facing door surface  14  and along the edge of the door nearest the latch assembly to cooperate with the middle bowed portion  74 . 
     FIG. 3  shows the door  10  in a closed position with the latch assembly  20  pressuring and securing the door in the closed position and compressing the door seal  12 . Preferably, the door seal  12  is a silicone bulb seal. 
     FIG. 4  shows a base friction disc  22  preferably made of  360  brass alloy and having three angularly and radially spaced transverse base friction disc mounting bores  24 . Each base friction disc mounting bore  24  may have a base friction disc counterbore  26 . 
     FIG. 5  shows a slotted rotating disc  32  that in the latch assembly  20  is rotatably centered on the base friction disc  22  (see  FIG. 11 ), the slotted rotating disc preferably is made of stainless steel, is sized to overlay the base friction disc, and has three angularly and radially spaced equal radius slots  34  sized and located to cooperate with the base friction disc mounting bores  24  and sized to receive and slidingly retain three spacer bushings  54  respectively with one bushing within each slot. Preferably, a center post mounting bore  36  is transverse through the slotted rotating disc  32  at its center. 
     FIG. 6  shows a center post  40  preferably made of stainless steel having a free end  42  and a mounting end  44  with the mounting end preferably having a mounting nub  46 . The center post  40  has a transverse lever bore  48  near its free end  42 , and a set screw receiving bore  50  intersecting said lever bore  48  near its midlength. 
     FIG. 7  shows a top view of a slotted rotating disc assembly  30  comprising the slotted rotating disc  32  and the center post  40 . 
   As best seen in  FIG. 8 , the center post  40  at its mounting end  44  is fixed perpendicularly to the center of the slotted rotating disc  32  preferably by welding. In the disc assembly  30 , the center post  40  has a transverse lever bore  48  spaced from and parallel to the slotted rotating disc  32 . Preferably, the mounting nub  46  is sized to fit within the center post mounting bore  36  of the slotted rotating disc  32  to facilitate the fixing of the center post  40  to the slotted rotating disc. In the assembled latch assembly  20 , a set screw  52  is removably fixed in the set screw receiving bore  50 . 
   As best seen in  FIG. 11 , three spacer bushings  54  are sized to slidingly fit and be retained respectively with one said bushing within each slot  34 . 
     FIG. 9  shows a top friction disc  60  preferably made of  360  brass alloy having a center post receiving bore  62  at its center sized to closely and rotatably receive the center post  40  during assembly of the latch assembly  20 . The top friction disc  60  has three angularly and radially spaced transverse top friction disc mounting bores  64 , said top friction disc is sized to overlay the slotted rotating disc  32 , and the top friction disc mounting bores in the assembled latch assembly  20  are coaxial respectively to the base friction disc mounting bores  24 . Each top friction disc mounting bore  64  may have a top friction disc upper counterbore  66 . 
     FIG. 10  shows a closing lever  70 . Preferably, the closing lever  70  has a first straight portion  72  transitioning into a middle bowed portion  74  and the middle bowed portion transitioning into a free straight portion  76  and preferably the first straight portion has an annular set screw receiving groove  78  located near the midlength of the first portion. During assembly of the latch assembly  20 , the lever  70  is rotatably and adjustably mounted in the lever bore  48  (see  FIGS. 2 ,  3 , and  11  to  15 ). 
     FIG. 11  is an exploded view of the components of the latch assembly  20  of the preferred embodiment. During assembly of the latch assembly  20 , three mounting screws  82  are inserted and retained respectively with one said screw through each top friction disc mounting bore  64 , each spacer bushing  54 , each slot  34 , and each base friction disc mounting bore  24 . 
     FIG. 12  shows an assembled latch assembly  20 , shows the center post  40  received in said center post receiving bore  62 , and shows a ball end  80  attached to the free straight portion  76  at its free end. 
   In the preferred embodiment of the latch assembly  20 , the longitudinal axis of the first straight portion  72  and the longitudinal axis of the free straight portion  76  are coaxial.  FIG. 13  shows with an double ended arrow marked on the end of the free straight portion  76  how the closing lever  70  can be rotated around the longitudinal axis of the first straight portion  74  to vary the lateral distance of the contact point of the middle bowed portion  74  relative to the lever contact strike plate  86 , shows a position of maximum displacement of the lever contact strike plate, and shows an alternative position of the closing lever. 
   The mounting screws  82  are used to attach the latch assembly  20  to the inward facing surface  6  of a bathtub side wall (as best seen in  FIGS. 14 and 15 ) adjacent to the bather entryway  8  and the latch assembly positioned to cooperatively interact with a swinging end  16  of an inwardly swinging entryway hinged door  10 . 
   Preferably, in the assembled latch assembly  20 , the spacer bushings  54  are retained within the slots  34  of the slotted rotating disc  32  and sized to space the base friction disc  22  from the top friction disc  60  and thereby limit the amount of tension that can be applied to the slotted rotating disc by the mounting screws  82  and thereby allowing the slotted disc assembly  30  to rotate between the friction discs  22  and  60 . 
     FIGS. 2 ,  3 , and  13  show an escutcheon  84  having an escutcheon center bore mounted over and concealing the base friction disc  22 , the slotted disc assembly  30 , the spacer bushings  54 , and the mounting screws  82 . 
   Preferably the spacer bushings  54  are made from stainless steel tubing. Preferably, the slotted rotating disc  32 , the center post  40 , the closing lever  70 , the set screw  52 , the mounting screws  82 , and the escutcheon  84  are made from stainless steel. 
   Alternatively, the middle bowed portion can comprise a descending segment having a longitudinal axis angling obliquely away from the longitudinal axis of said first straight portion, said descending segment transitioning into a zone of maximum lateral displacement away from the longitudinal axis of said first straight portion, and said zone transitioning into an ascending segment having a longitudinal axis angling obliquely back towards the longitudinal axis of said first straight portion. 
   Alternatively, the middle bowed portion can comprise a curved portion that first curves away from the longitudinal axis of said first straight portion and then curves back towards the longitudinal axis of said first straight portion. 
   Alternatively, the first straight portion may have an annular set screw receiving groove located near the free end of the first straight portion. 
   The preceding description and exposition of the invention is presented for purposes of illustration and enabling disclosure. It is neither intended to be exhaustive nor to limit the invention to the precise forms disclosed. Modifications or variations in the invention in light of the above teachings that are obvious to one of ordinary skill in the art are considered within the scope of the invention as determined by the appended claims when interpreted to the breath to which they fairly, legitimately and equitably are entitled.

Summary:
A walk-in bathtub adjustable door latch assembly incorporates an adjustably positionable closing lever to secure and to adjustably move and adjustably pressure a hinged door of a walk-in bathtub into a close sealing position in a bather entryway to guard against water leakage through the bather entryway.