Sinks and drains for sinks permitting the attachment of the drain to the sink such that the drain is substantially disposed below the top surface of the sink basin, and such that there is no discernable separation between the base of the sink basin and the drain when viewed from above the sink. A method of making a sink such that there is no discernable separation between the base of the sink basin and the drain when viewed from above the sink.

CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This patent application claims the benefit of U.S. Provisional Patent Application Nos. 61/467,858, filed Mar. 25, 2011, and 61/490,138, filed May 26, 2011, which are incorporated by reference in their entireties herein. 
     
    
     BACKGROUND 
       [0002]    Sinks have drains for permitting water to drain from the sink into a plumbing system. During installation, drains are typically inserted into the interior of the sink basin and dropped into an opening at the base of the basin. The drain has a rim with a diameter exceeding the diameter of the opening such that the rim rests on the top surface of the base of the sink basin. Often, the portion of the base surrounding the opening has a countersink portion such that the rim of the drain is generally flush with the adjacent portion of the base of the sink. Nonetheless, a groove is present between the rim of the drain and the sink base that is difficult to clean and susceptible to bacterial growth. In addition, the presence of the groove is visible to a user and aesthetically unappealing. 
       BRIEF SUMMARY 
       [0003]    Embodiments of sinks and drains for sinks are disclosed herein. The embodiments permit the attachment of a drain to a sink such that the drain is substantially disposed below the top surface of the sink basin, and such that there is no discernable separation between the base of the sink basin and the drain when viewed from above the sink. A method of making a sink is also disclosed wherein there is no discernable separation between the base of the sink basin and the drain when viewed from above the sink. 
         [0004]    A sink is described comprising a sink basin, a drain entry portion, a flange plate, a strainer, a first seal, and a second seal. The sink basin can have a sidewall and a base. The base can have an opening. The drain entry portion can be disposed at the opening and attached to the base. The drain entry portion can extend away from the base. The drain entry portion can have a lip for receiving the first seal. The flange plate can have an inner edge portion and an outer edge portion. The outer edge portion can be in contact with the first seal. The first seal can be disposed between the lip and the outer edge portion. The strainer can be disposed near the inner edge portion. The second seal can be disposed between the strainer and the inner edge portion. 
         [0005]    A drain is also disclosed comprising a first seal, a drain entry portion, a flange plate, a strainer, and a second seal. The drain entry portion can have a lip for receiving the first seal. The flange plate can have an inner edge portion and an outer edge portion. The outer edge portion can be in contact with the first seal. The first seal can be disposed between the lip and the outer edge portion. The strainer can be disposed near the inner edge portion. The second seal can be disposed between the strainer and the inner edge portion. 
         [0006]    A method of making a sink is also described. The method comprises forming a sink basin having a sidewall and a base, providing a drain entry portion, welding the drain entry portion to the base at the opening, and grinding the weld at the opening such that the drain entry portion appears integrally formed with the base when viewing into the sink basin. The base can have an opening. The drain entry portion can be cylindrical. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a perspective view of a sink; 
           [0008]      FIG. 2  is a sectional view of a drain for the sink of  FIG. 1 ; 
           [0009]      FIG. 3  is a sectional view of a second embodiment of a drain for the sink of  FIG. 1 ; 
           [0010]      FIG. 4  is a sectional view of a third embodiment of a drain for the sink of  FIG. 1 ; 
           [0011]      FIG. 5  is a perspective view of another embodiment of a sink; 
           [0012]      FIG. 6  is a sectional view of an embodiment of a drain for the sink of  FIG. 5 ; 
           [0013]      FIG. 7  is a sectional view of an embodiment of a drain for a sink attached to a garbage disposer; 
           [0014]      FIG. 8  is a fragmentary bottom perspective view showing the drain of  FIG. 7 ; 
           [0015]      FIG. 9  is a sectional view of a drain entry portion welded to a sink; 
           [0016]      FIG. 10  is a sectional view of another embodiment of a drain entry portion welded to a sink; and 
           [0017]      FIG. 11  is a sectional view of a further embodiment of a drain entry portion welded to a sink. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    Referring to  FIG. 1 , a sink  100  with the appearance of an edgeless drain is shown. The sink  100  can include one or more sink basins  102  and a rim  104 . The sink basin  102  can include one or more sidewalls  106  and a base  108 . The base  108  can include an opening  110  for a drain. The sidewalls  106  and base  108  can form an interior surface of the basin  102  to retain water and washable items. The rim  104  can be used to support the basin  102  in an above-mount arrangement or under-mount arrangement with respect to a counter. The sink  100  can be made of any suitable material, such as stainless steel. 
         [0019]    Referring to  FIG. 2 , a drain  101  is shown that can include a drain entry portion  112 , a flange plate  114 , a strainer  116 , a drain pipe  118 , and a cover  120 . The drain entry portion  112  can be cylindrical and can extend from the bottom of the sink basin at the opening for the drain  101 . The drain entry portion  112  can include a first end portion  122  and a second end portion  124 . In some embodiments, the drain entry portion  112  can be formed as part of the sink  100 . In other embodiments, the drain entry portion  112  can be a component separately manufactured from the sink  100 . The first end portion  122  of the drain entry portion  112  can be welded to the base of the sink to fix the drain entry portion  112  to the sink basin at the opening. In order to conceal the welded intersection between the drain entry portion  112  and the base, a grinding and polishing operation can be applied such that the intersection is hidden to a user looking into the sink basin. In addition, because the drain entry portion  112  can be mounted from below without the need for a drain rim to rest on the base, there is no groove between the drain  101  and the sink basin  102 . From a user's perspective, the drain opening leads directly into the drain  101 . The weld between the sink basin and the drain entry portion  112  can be accomplished in any suitable manner, such as with a shielding gas weld. 
         [0020]      FIGS. 9-11  show examples of suitable embodiments of a drain entry portion welded to a base of a sink. It will be appreciated, however, that the drain entry portion can be coupled to the sink via any suitable manner. 
         [0021]    Referring to  FIG. 9 , the drain entry portion  612  can include a radially extending flange  680 . The flange  680  can be disposed against the underside of the sink base  108 . The drain entry portion  612  can have an interior diameter that is smaller than the opening  110  of the sink  100  such that there is a portion of the flange  680  extending inward from the opening  110  that can receive a solder material  682  for welding the drain entry portion  612  to the sink  100 . As discussed, after welding, a grinding and polishing operation can be applied to the weld such that the intersection between the drain entry portion  612  and the sink  100  is hidden to a user looking into the sink basin  102 . 
         [0022]    Turning to  FIG. 10 , the drain entry portion  712  can include a radially extending flange  780 . The flange  780  can be disposed within the opening  110  such that the flange abuts the portion of the sink base  108  forming the opening  110 . Thus, the perimeter of the flange  780  has a diameter that is smaller than the opening  110  of the sink  100  such that the flange  780  fits within the opening  110 . The thickness of the flange  780  can be smaller than the thickness of the sink base  108  such that a space is formed on the upper surface of the flange  780  for receiving a solder material  782  for welding the drain entry portion  712  to the sink  100 . As discussed, after welding, a grinding and polishing operation can be applied to the weld such that the intersection between the drain entry portion  612  and the sink  100  is hidden to a user looking into the sink basin  102 . 
         [0023]    As shown in  FIG. 11 , the drain entry portion  812  can include a radially extending flange  880 . The flange  880  can be disposed away from the edge  884  of the drain entry portion  812  on the first end portion  822 . The flange  880  can be disposed against the underside of the sink base  108 , and the edge  884  of the drain entry portion  812  can have an exterior diameter that is smaller than the opening  110  of the sink  100 . The flange  880  can be located on the drain entry portion  812  a sufficient distance from the edge such that the edge is disposed below the upper surface of the sink base  102  and such that the edge  884  can receive a solder material  882  for welding the drain entry portion  812  to the sink  100 . As discussed, after welding, a grinding and polishing operation can be applied to the weld such that the intersection between the drain entry portion  812  and the sink  100  is hidden to a user looking into the sink basin  102 . 
         [0024]    Referring again to  FIG. 2 , the second end portion  124  of the drain entry portion  112  can include a lip  126  for receiving a seal  128 . The flange plate  114  can have an outer edge portion  130  and an inner edge portion  132 . The outer edge portion  130  of the flange plate  114  can rest on the seal  128  such that the seal  128  prevents water inside the drain  101  from passing between the intersection of the drain entry portion  112  and the flange plate  114 . The inner edge portion  132  of the flange plate  114  can receive a lip  134  of the drain pipe  118  for supporting the drain pipe  118 . 
         [0025]    The strainer  116  can be disposed above the lip  134  of the drain pipe  118  and the inner edge portion  132  of the flange plate  114 . The strainer  116  can include a seal  136  for contacting the lip  134  of the drain pipe  118  and preventing the passage of water in the drain  101  past the seal  136 . The strainer  116  can be press fit within the flange plate  114 . The strainer  116  can have one or more openings in the bottom of the strainer to permit water to flow past the strainer  116  and into the drain pipe  118 . 
         [0026]    The drain  101  can include a cover  120  over the drain entry portion  112 , the flange plate  114 , and the strainer  116 . The cover  120  can be secured to the sink with a locking nut  138 . The drain pipe  118  can be threaded to receive the locking nut  138 , and the locking nut  138  can be tightened to enhance the seal force applied between the drain entry portion  112  and the flange plate  114 . A coupler  140  can be used to attach the drain pipe  118  to a pipe  142  leading to a trap. 
         [0027]    A removeable strainer basket  144  can be disposed within the drain  101 . The strainer basket  144  can include a basket portion  146  for capturing solids and a stopper  148  that can be lowered into the strainer  114  to plug the drain  101 . 
         [0028]    Turning to  FIG. 3 , a second embodiment of a drain  201  is shown that can include a drain entry portion  212 , an attachment portion  250 , a strainer  216 , and a drain pipe  218 . The drain entry portion  212  can be cylindrical and can extend from the bottom of the sink basin at the opening for the drain  201 . The drain entry portion  212  can include a first end portion  222  and a threaded exterior surface  252 . The drain entry portion  212  can be a component separately manufactured from the sink. The first end portion  222  of the drain entry portion  212  can be welded to the base to fix the drain entry portion  212  to the sink basin at the opening. In order to conceal the welded intersection between the drain entry portion  212  and the base, a grinding and polishing operation can be applied such that the intersection is hidden to a user looking into the sink basin. In addition, because the drain entry portion  212  can be mounted from below without the need for a drain rim to rest on the base, there is no groove between the drain  201  and the sink basin. From a user's perspective, the drain opening leads directly into the drain  201 . The weld between the sink basin and the drain entry portion  212  can be accomplished in any suitable manner, such as with a shielding gas weld. 
         [0029]    The attachment portion  250  can have a threaded surface  254  and an inner edge portion  232 . The attachment portion threaded surface  254  can be received and tightened to the threaded surface  252  of the drain entry portion  212 . The inner edge portion  232  of the attachment portion  250  can receive a lip  234  of the drain pipe  218  for supporting the drain pipe  218 . 
         [0030]    The strainer  216  can be disposed above the lip  234  of the drain pipe  218  and the inner edge portion  232  of the attachment portion  250 . The strainer  216  can include a seal  236  for contacting the lip  234  of the drain pipe  218  and preventing the passage of water in the drain  201  past the seal  236 . The strainer  216  can be press fit within the attachment portion  250 . The strainer  216  can have one or more openings in the bottom of the strainer to permit water to flow past the strainer  216  and into the drain pipe  218 . The drain pipe  218  can be threaded to receive a coupler that can be used to attach the drain pipe to a pipe leading to a trap. 
         [0031]    A removeable strainer basket  244  can be disposed within the drain  201 . The strainer basket  244  can include a basket portion  246  for capturing solids and a stopper  248  that can be lowered into the strainer  216  to plug the drain  201 . 
         [0032]    Referring to  FIG. 4 , a third embodiment of a drain  301  is shown that can include a drain entry portion  312 , an attachment portion  350 , a strainer  316 , and a drain pipe  318 . The drain entry portion  312  can be cylindrical and can extend from the bottom of the sink basin at the opening for the drain  301 . In this embodiment, the drain entry portion  312  can be formed from the sink basin during the drawing process to shape the sink. Thus, the drain entry portion  312  can be integrally formed to lead directly from the sink basin to the drain  301 . Threads  352  can be welded or otherwise attached to the drain entry portion  312 . 
         [0033]    The attachment portion  350  can have a threaded surface  354  and an inner edge portion  332 . The attachment portion threaded surface  354  can be received and tightened to the threads  352  of the drain entry portion  312 . The inner edge portion  332  of the attachment portion  350  can receive a lip  334  of the drain pipe  318  for supporting the drain pipe  318 . 
         [0034]    The strainer  316  can be disposed above the lip  334  of the drain pipe  318  and the inner edge portion  332  of the attachment portion  350 . The strainer  316  can include a seal  336  for contacting the lip  334  of the drain pipe  318  and preventing the passage of water in the drain  301  past the seal. The strainer  316  can be press fit within the attachment portion  350 . The strainer  316  can have one or more openings in the bottom of the strainer to permit water to flow past the strainer  316  and into the drain pipe  318 . The drain pipe  318  can be threaded to receive a coupler that can be used to attach the drain pipe to a pipe leading to a trap. 
         [0035]    A removeable strainer basket  344  can be disposed within the drain  301 . The strainer basket  301  can include a basket portion  346  for capturing solids and a stopper  348  that can be lowered into the strainer  316  to plug the drain  301 . 
         [0036]      FIGS. 5 and 6  show another embodiment of an edgeless drain  401  suitable for use with a non-metallic sink  400 , such as a sink made of granite or other suitable stone. The drain  401  can include a first drain entry portion  411 , a second drain entry portion  412 , a flange plate  414 , a strainer  416 , a drain pipe  418 , and a cover  420 . The first drain entry portion  411  can be cylindrical and can extend from the bottom of the sink basin at the opening for the drain  401 . Similar to the embodiment of  FIG. 4 , the first drain entry portion  411  can be formed as part of the sink basin during the process of making the sink. Thus, the first drain entry portion  411  leads directly from the sink basin into the drain  401 . 
         [0037]    The second drain entry portion  412  can include a first end portion  422  and a second end portion  424 . The second drain entry portion  412  can be a component separately manufactured from the sink. The first end portion  422  of the second drain entry portion  412  can include one or more apertures such that the drain entry portion  412  can be fastened to the bottom of the sink using suitable fasteners  456  disposed through the apertures, such as one or more screws. 
         [0038]    The second end portion  424  of the second drain entry portion  412  can include a lip  426  for receiving a seal  428 . The flange plate  414  can have an outer edge portion  430  and an inner edge portion  432 . The outer edge portion  430  of the flange plate  414  can rest on the seal  428  such that the seal  428  prevents water inside the drain  401  from passing between the intersection of the second drain entry portion  412  and the flange plate  414 . The inner edge portion  432  of the flange plate  414  can receive a lip  434  of the drain pipe  418  for supporting the drain pipe  418 . 
         [0039]    The strainer  416  can be disposed above the lip  434  of the drain pipe  418  and the inner edge portion  432  of the flange plate  414 . The strainer  416  can include a seal  436  for contacting the lip  434  of the drain pipe  418  and preventing the passage of water in the drain  401  past the seal  436 . The strainer  416  can be press fit within the flange plate  414 . The strainer  416  can have one or more openings in the bottom of the strainer to permit water to flow past the strainer  416  and into the drain pipe  418 . 
         [0040]    The drain  401  can include a cover  420  over the second drain entry portion  412 , the flange plate  414 , and the strainer  416 . The cover  420  can be secured to the sink with a locking nut  438 . The drain pipe  418  can be threaded to receive the locking nut  438 , and the locking nut  438  can be tightened to enhance the seal force applied between the second drain entry portion  412  and the flange plate  414 . A coupler  440  can be used to attach the drain pipe  418  to a pipe  442  leading to a trap. 
         [0041]    A removeable strainer basket  444  can be disposed within the drain  401 . The strainer basket  444  can include a basket portion  446  for capturing solids and a stopper  448  that can be lowered into the strainer  416  to plug the drain  401 . 
         [0042]    It will be appreciated that the above-described sink and drain embodiments may be utilized with a garbage disposer. For example,  FIGS. 7 and 8  show an embodiment of a drain  501  attached to a garbage disposer  560 . In this embodiment, the drain  501  can include a drain entry portion  512 , a disposer attachment ring  562 , a strainer  516 , and a disposer assembly  564 . The drain entry portion  512  can be cylindrical and can extend from the bottom of the sink basin at the opening for the drain  501 . The drain entry portion  512  can include a first end portion  522  and a threaded exterior surface  552 . The drain entry portion  512  can be a component separately manufactured from the sink. The first end portion  522  of the drain entry portion  512  can be welded to the base to fix the drain entry portion  512  to the sink basin at the opening. In order to conceal the welded intersection between the drain entry portion  512  and the base, a grinding and polishing operation can be applied such that the intersection is hidden to a user looking into the sink basin. In addition, because the drain entry portion  512  can be mounted from below without the need for a drain rim to rest on the base, there is no groove between the drain  501  and the sink basin. From a user's perspective, the drain opening leads directly into the drain  501 . The weld between the sink basin and the drain entry portion  512  can be accomplished in any suitable manner, such as with a shielding gas weld. 
         [0043]    The disposer attachment ring  562  can have a threaded surface  566  and a lower portion  568 . The flange plate threaded surface  552  can be received and tightened to the threaded exterior surface  566  of the drain entry portion  512 . The lower portion  568  can have a detent  570  for receiving a snap ring  572 . The strainer  516  can be disposed above detent  570 . The strainer  516  can have one or more openings in the bottom of the strainer to permit water to flow past the strainer  516  and into the disposer  560 . 
         [0044]    The disposer assembly  564  can include a backup flange  574  and a mounting ring  576 . The backup flange  574  can be generally triangular and the mounting ring  576  can have a plurality of tightening screws  578  for contacting the backup flange  574  near each vertex of the backup flange  574 . During tightening of the screws  578 , the mounting ring  576  can be retained to the disposer attachment ring  562  by the snap ring  572 . As is known to those of skill in the art, the disposer  560  can include a bracket for hanging the disposer from the mounting ring. 
         [0045]    A removeable strainer basket  544  can be disposed within the drain  501 . The strainer basket  544  can include a basket portion  546  for capturing solids and a stopper  548  that can be lowered into the strainer  516  to plug the drain  501 . 
         [0046]    All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein. 
         [0047]    The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. 
         [0048]    Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.