Self-locking grate for deck drain fitting

Abstract

A self-locking grate for a drain fitting body includes a plate having strainer holes and arcuate elongated openings near the periphery of the grate. Enlarged diameter portions of the elongated openings fit over studs connected to a drain, and the grate can be rotated to engage the studs, so that the grate is wedged to the drain fitting body without the use of screws. An inclined ledge, formed in the elongated openings, acts as a cam surface to wedge against the grate as it is rotated into the locked position. Despite the absence of screws, the grate is unlikely to loosen due to vibration or shock. A tool capable of simultaneously engaging distinct holes in the grate can be used to rotate the grate between the locked and unlocked positions. The invention also includes a kit for converting a conventional drain fitting and grate into a drain fitting and grate of the present invention.

1 . A self-locking grate for a drain fitting, comprising: 
 a plate having a plurality of strainer holes, the plate further comprising a plurality of elongated openings which are distinct from the strainer holes, each elongated opening including a region of enlarged diameter relative to other regions of said elongated opening, the elongated openings defining at least a generally circular arc.    
     
     
         2 . The grate of  claim 1 , wherein at least one of said elongated openings has a ledge having a depth which varies along said opening.  
     
     
         3 . The grate of  claim 1 , wherein the plate has a generally circular shape, the plate having a periphery, and wherein the elongated openings are located in a vicinity of the periphery of the plate.  
     
     
         4 . The grate of  claim 2 , wherein the plate has a generally circular shape, the plate having a periphery, and wherein the elongated openings are located in a vicinity of the periphery of the plate.  
     
     
         5 . The grate of  claim 1 , further comprising a tool having means for supporting a pair of spaced-apart prongs, the prongs being sized to fit simultaneously within at least two of said strainer holes and said openings, wherein movement of the tool, when the prongs are inserted into said holes or openings, causes rotation of the grate.  
     
     
         6 . The grate of  claim 5 , wherein at least one prong of the tool is pivotable relative to another prong, wherein positions of the prongs can be adjusted so that the prongs fit simultaneously into holes and/or openings of the grate.  
     
     
         7 . In combination, a self-locking grate and a drain fitting body, 
 the grate comprising a plate having a plurality of strainer holes, the plate further comprising a plurality of elongated openings which are distinct from the strainer holes, each elongated opening including a region of enlarged diameter relative to other regions of said elongated opening, the elongated openings defining at least a generally circular arc, and    wherein the drain fitting body comprises means for supporting a plurality of studs, wherein the studs are positioned to coincide with positions of said regions of enlarged diameter of said elongated openings, and wherein the studs are sized to pass through said regions of enlarged diameter but not through other regions of said elongated openings, wherein the studs can engage the grate when the grate has been rotated.    
     
     
         8 . The combination of  claim 7 , wherein each stud has a head, wherein at least one of said elongated openings has an inclined ledge having a depth which varies along said opening, the inclined ledge comprising a cam surface for wedging the grate against an underside of the head of the stud.  
     
     
         9 . The combination of  claim 7 , wherein the plate has a generally circular shape, the plate having a periphery, and wherein the elongated openings are located in a vicinity of the periphery of the plate.  
     
     
         10 . The combination of  claim 8 , wherein the plate has a generally circular shape, the plate having a periphery, and wherein the elongated openings are located in a vicinity of the periphery of the plate.  
     
     
         11 . The combination of  claim 7 , further comprising a tool having means for supporting a pair of spaced-apart prongs, the prongs being sized to fit simultaneously within at least two of said strainer holes and said openings, wherein movement of the tool, when the prongs are inserted into said holes or openings, causes rotation of the grate relative to the drain fitting body.  
     
     
         12 . The combination of  claim 11 , wherein at least one prong of the tool is pivotable relative to another prong, wherein positions of the prongs can be adjusted so that the prongs fit simultaneously into holes and/or openings of the grate.  
     
     
         13 . A method of installing a grate on a drain fitting body, comprising: 
 a) placing a grate onto a drain, wherein the drain includes a plurality of studs, and wherein the grate includes a plurality of elongated openings, each of the elongated openings having an enlarged diameter portion sized to accommodate said studs, the grate being placed such that the studs pass through the enlarged diameter portions of said openings, and    b) rotating the grate so that the studs are no longer positioned within the enlarged diameter portions, wherein the grate becomes locked onto the drain fitting body.    
     
     
         14 . The method of  claim 13 , wherein the enlarged diameter portions are located at one end of the elongated openings, and wherein the elongated openings have an opposite end at which the opening has a diameter smaller than that of the enlarged diameter portion, and wherein step (b) includes rotating the grate until the studs are located in a vicinity of said opposite end of the elongated openings.  
     
     
         15 . The method of  claim 13 , further comprising turning the grate until the studs are positioned within the enlarged diameter portions, and lifting the grate from the drain.  
     
     
         16 . The method of  claim 13 , wherein the rotating step comprises applying force to a tool which is in engagement with the grate, the tool having means for supporting a pair of spaced-apart prongs, the prongs being sized to fit simultaneously within at least two holes or openings in the grate, wherein movement of the tool, when the prongs are inserted into said holes or openings, and torque is applied, causes rotation of the grate relative to the drain.  
     
     
         17 . The method of  claim 16 , wherein at least one prong of the tool is pivotable relative to another prong, and wherein the method includes the step of adjusting a position of said at least one prong so that the prongs fit simultaneously into holes and/or openings of the grate.  
     
     
         18 . A kit for modifying a drain fitting so as to accommodate a self-locking grate, the kit comprising: 
 a) a plate having a plurality of strainer holes, the plate further comprising a plurality of elongated openings which are distinct from the strainer holes, each elongated opening including a region of enlarged diameter relative to other regions of said elongated opening, the elongated openings defining at least a generally circular arc, and    b) means for providing studs in a drain fitting, the studs having heads which are sized to engage at least a portion of the elongated openings of the plate.    
     
     
         19 . The kit of  claim 18 , further comprising at least one tap for creating a threaded bore for receiving said studs in the drain fitting.  
     
     
         20 . The kit of  claim 18 , further comprising a tool having means for supporting a pair of spaced-apart prongs, the prongs being sized to fit simultaneously within at least two of said strainer holes and said openings, wherein movement of the tool, when the prongs are inserted into said holes or openings, applies a torque to the grate.