Filter proximity nozzle

Abstract

A suction nozzle assembly, comprising a tube coupled to a pressure sink at a distal side thereof, a nozzle, a resilient element which couples said nozzle to a proximal side of said tube and a deformable housing which bridges a gap between said proximal side of said tube and said nozzle. Optionally, a pressure equalizer, for example, a through aperture, is formed in said nozzle.

1 . A suction nozzle assembly for cleaning a water filtration screen, comprising:
 a pressure sink;   a nozzle;   a resilient element which resiliently couples said nozzle to said pressure sink, said resilient element is sized and positioned to move said nozzle towards said filtration screen, said resilient element causes a gap to be formed between said pressure sink and said nozzle; and   a deformable housing which bridges said gap between said pressure sink and said nozzle, said housing is sized and positioned to accommodate said gap as said nozzle moves relative to said filtration screen.   
     
     
         2 . An assembly according to  claim 1 , wherein said housing comprises an elastic tube. 
     
     
         3 . An assembly according to  claim 1 , wherein said housing comprises a bellows, which bellows also acts as said resilient element. 
     
     
         4 . (canceled) 
     
     
         5 . An assembly according to  claim 1 , wherein said housing is sized and positioned to deform to extend in a direction perpendicular to a flow in said nozzle. 
     
     
         6 . An assembly according to  claim 1 , comprising at least one pressure-equalizing aperture formed in one or both of said nozzle and said housing and providing fluid communication between said gap and an outside of said nozzle assembly. 
     
     
         7 . An assembly according to  claim 6 , wherein at least one of said at least one pressure equalizing aperture is formed in said nozzle. 
     
     
         8 . An assembly according to  claim 6 , wherein at least one of said at least one pressure equalizing aperture is formed in said housing. 
     
     
         9 . An assembly according to any of  claim 6 , wherein at least one of said at least one pressure equalizing aperture is located inside said nozzle assembly and adjacent a section of said nozzle having a projection on a plane perpendicular to a flow in said nozzle. 
     
     
         10 . An assembly according to  claim 6 , wherein at least one of said at least one pressure equalizing aperture is sized and positioned to prevent or reduce deformation of said housing by said pressure sink. 
     
     
         11 . An assembly according to  claim 6 , wherein at least one of said at least one pressure equalizing aperture is sized and positioned to prevent or reduce pressure reduction in said housing by said pressure sink. 
     
     
         12 . An assembly according to  claim 6 , wherein at least one of said at least one pressure equalizing aperture is sized and positioned to prevent or reduce retraction of said nozzle by said pressure sink. 
     
     
         13 - 17 . (canceled) 
     
     
         18 . An assembly according to  claim 1 , wherein said gap includes an axial gap. 
     
     
         19 . (canceled) 
     
     
         20 . A water filtering system comprising:
 a water filter layer;   an assembly according to  claim 1 ; and   a movement actuator configured to move said nozzle assembly over at least 50% of a surface of said layer,   wherein said assembly is configured to maintain a gap of 5 mm or less from said filter over all of said movement of said at least 50% of surface.   
     
     
         21 - 22 . (canceled) 
     
     
         23 . A nozzle assembly according to  claim 1 , comprising at least one pressure sink coupled to said gap and positioned to equalize pressure between said gap and an outside of said nozzle assembly. 
     
     
         24 . (canceled) 
     
     
         25 . A method of approximating a nozzle coupled, with a gap to a pressure sink, to a water filter, comprising:
 resiliently urging said nozzle towards said filter; and   allowing sufficient fluid flow between an outside of said nozzle and said gap, so as to reduce a retraction of said nozzle by said pressure sink.   
     
     
         26 . A method according to  claim 25 , wherein said resiliently urging comprises resiliently urging using a bellows which also bridges said gap, said bellows is sized and positioned to move said nozzle relative to said filter. 
     
     
         27 . A method according to  claim 25 , wherein said allowing sufficient flow comprises allowing sufficient flow through one or more pressure-equalizing channels in said nozzle. 
     
     
         28 . A suction nozzle assembly for cleaning a water filtration screen, comprising:
 a tube coupled to a pressure sink at a proximal side thereof;   a nozzle; and   a deformable housing which bridges a gap between said distal side of said tube and said nozzle and which couples said nozzle to a distal side of said tube and which said housing is sized and positioned to allows tilting motion of said nozzle relative to said tube to adjust to surface variations of said filtration screen.   
     
     
         29 . A nozzle assembly according to  claim 1 , comprising a tube coupled to said pressure sink at a proximal side thereof and to said resilient element at a distal side thereof. 
     
     
         30 . A nozzle assembly according to  claim 1 , wherein said deformable housing maintains said gap.