Drain

Abstract

A grid drain for use on a sink to prevent large objects from entering the drain. The drain includes a tube ( 12 ) and a cover ( 20 ) that attaches to the top of the tube. The cover has a flat middle ( 72 ) and has a peripheral portion ( 74 ) that is curved to form a dome, with two circles of holes ( 46, 52 ).

What is claimed is: 
     
         1 . A drain that allows water to pass through while blocking large pieces of solid material, said drain including a tube ( 12 ) with a vertical axis ( 14 ) and a tube top forming a support surface ( 24 ), said drain including a cover ( 20 ) that covers said tube top and that has a plurality of drain holes, wherein:
 said cover is dome-shaped, with a cover periphery ( 30 ) that lies on said tube support surface, and with a cover top ( 70 ) lying along said vertical axis, said cover having a ring of inner holes ( 50 ) spaced about said axis and said cover has a ring of outer holes ( 44 ) spaced about said axis and lying further from said axis than said inner holes;   each of said inner holes has a primarily vertical hole axis ( 92 ) and each of said outer holes has a center with an outer hole axis ( 94 ) angled between 15° and 75° to said tube vertical axis.   
     
     
         2 . The drain described in  claim 1  wherein:
 said cover has twice as many of said outer holes as said inner holes, with each outer hole lying radially halfway between two inner holes as seen in a top view taken along said axis. 
 
     
     
         3 . The drain described in  claim 1  wherein:
 said cover has a flat middle portion ( 72 ) lying on said axis, that forms said inner holes; 
 said cover has a radially outer part ( 74 ) that is radially spaced from said vertical axis by more than half a radius of said cover periphery, with said outer part having curved inner and outer surfaces, that form a dome. 
 
     
     
         4 . A drain that allows water to pass through while blocking solid material, said drain including a tube with a vertical axis and an open top, and a cover that covers said open top and that has a plurality of holes, wherein:
 said cover is dome-shaped, with a cover periphery ( 30 ) that lies on said tube top, with a cover upper part ( 70 ) having an inner circle of holes ( 40 ), and with a cover peripheral portion ( 70 ) having an outer circle of holes ( 46 );   said holes of said outer circle of holes having vertical axis ( 92 ) and said holes of said lower circle of holes have axes angled between 15° and 75° from the vertical.   
     
     
         5 . The drain described in  claim 4  wherein:
 said cover has a periphery with top and bottom surfaces ( 80 ,  82 ) that each extends in a quarter of a circle, as seen in a sectional view taken on said vertical axis, to form said dome.