Filtration system

Abstract

A filtration system is disclosed, which comprises a filtration-element within a filtration chamber, and a valving device located exteriorly to the filtration chamber, for reversing the direction of fluid-flow through the filtration-element for backwashing. The valving device thus functions as a common valve for handling both filtration and backwash. The common valve is based on a linearly-movable plug located inside a valve housing which is communicable with the filtration chamber, with a source of fluid to be filtered, and with evacuation port for backwash fluid, through three respective openings in the valve housing, and is characterized by an uninterrupted bend-free flow-channel extending at least from exteriorly to an inlet opening of the valve housing, to the body of the filtration-element whenever the common valve is in a filtration mode of operation.

The invention claimed is: 
     
       1. A filtration system comprising: a filtration chamber, a filtration-element housed within the filtration chamber, wherein the filtration-element comprises a body of the filtration-element, a common valve comprising a valve housing in fluid communication with the filtration chamber, with a source of fluid to be filtered, and with evacuation port for backflush fluid, through three respective openings in the valve housing, wherein the common valve, the filtration chamber, and a tube segment connecting therebetween, are mutually configured to provide for an uninterrupted bend-free flow-channel extending at least from exteriorly to an inlet opening of the common valve, to the body of the filtration-element whenever the common valve is in a filtration mode of operation. 
     
     
       2. The filtration system according to  claim 1 , wherein the bend-free flow-channel has a cross section area perpendicularly to a longitudinal axis thereof of about 50% or more of the area of the inlet opening of the common valve. 
     
     
       3. The filtration system according to  claim 1 , wherein the common valve comprises a plug that is linearly movable within a central void of the common valve, wherein a backwall of the plug has a protrusion fitting within a matching immovable recess, wherein the matching immovable recess extends between an evacuation-outlet formed in a wall of the valve housing and between the central void and has an internal free space having a predetermined volume, wherein said protrusion is configured to at least partially occupy the internal free space when the plug is in transition, between a backmost position of the plug within the void and a position closer to a foremost position of the plug within the void until full departure of the protrusion out from within the immovable recess, thereby reducing evacuation of fluid through the immovable recess during transition of the plug between a filtration mode of operation and a backflush mode of operation as a function of a degree of a volume of the recess, occupied by the protrusion. 
     
     
       4. The filtration system according to  claim 3 , wherein the common valve comprises a plug that is linearly movable between a first position and a second position, wherein the first position is associated with a filtration mode of operation, wherein the second position is associated with a backflush mode of operation, wherein the plug comprises a rear protrusion configured to restrict fluid passage from a central void of the valve to the evacuation port during linear motion of the plug from the first position to the second position, wherein at least a portion of a predetermined volume of the recess is occupied by the rear protrusion for at least first 30% of full extent of the linear motion whereby waste of fluid through the evacuation port is reduced as a function of a degree of a volume of the recess occupied by the protrusion. 
     
     
       5. The filtration system according to  claim 4 , wherein the rear protrusion is cylindrical, a height of which is oriented parallel to a direction of the linear motion. 
     
     
       6. The filtration system according to  claim 1 , wherein the common valve comprises a plug that is linearly movable between a first position and a second position, wherein the first position is associated with a filtration mode of operation, wherein the second position is associated with a backflush mode of operation, wherein the plug comprises a front protrusion configured to enter the inlet opening for thereby reducing a flow rate of fluid into the inlet opening during linear motion of the plug from the first position to the second position, wherein at least a portion of the front protrusion penetrates through the inlet opening for at least last 30% of full extent of the linear motion, whereby waste of fluid through the evacuation port is reduced as a function of a degree of penetration of the front protrusion through the inlet opening. 
     
     
       7. The filtration system according to  claim 6 , wherein the front protrusion is conically like, tapering towards the inlet opening. 
     
     
       8. The filtration system according to  claim 1 , wherein an angle between a longitudinal axis of the tube segment and a longitudinal axis of the filtration chamber is between 35 and 55 degrees. 
     
     
       9. The filtration system according to  claim 6 , wherein the tube segment has an elliptically shaped cross section perpendicularly to its longitudinal axis, flattened in a direction parallel to the direction of linear motion, thereby allowing for a shortening the extent of linear motion of the plug per a given cross section area of the tube segment. 
     
     
       10. The filtration system according to  claim 1 , wherein a proximal end of the filtration chamber, at least most of the housing of the common valve and the tube segment are inseparable members of a single piece of material. 
     
     
       11. The filtration system according to  claim 1 , wherein a flow through a first opening in a housing of the filtration chamber is into the chamber during filtration mode of operation and out of the chamber during backflush mode of operation, wherein a flow through a second opening in a housing of the filtration chamber is out of the chamber during filtration mode of operation and into the chamber during backflush mode of operation. 
     
     
       12. A twin filtration system comprising a first and a second filtration systems, each according to  claim 1 , said first and second filtration systems are connected together in mirroring configuration, wherein the inlet opening of the common valve in the first system is facing the and having a line of sight with the inlet opening of the common valve in the second system through a flow splitter for a fluid to be filtered. 
     
     
       13. A twin filtration system according to  claim 12 , wherein the flow splitter comprises a pair of arched tubes diverging from a central common tube. 
     
     
       14. A twin filtration system comprising a first and a second filtration systems, each according to  claim 1 , said first and second filtration systems are connected together in mirroring configuration, wherein an outlet opening of the filtration chamber in the first system is facing the and having a line of sight with an outlet opening of the filtration chamber in the second system through a flow combiner for a filtered fluid. 
     
     
       15. The twin filtration system according to  claim 14 , wherein the flow combiner comprises a pair of arched tubes diverging from a central common tube. 
     
     
       16. The twin filtration system according to  claim 15 , wherein a radius of a largest inner curve of each of the arched tubes is between about 100% and 150% the diameter of the central common tube. 
     
     
       17. The twin filtration system according to  claim 15 , wherein an inner cross section area of the central common tube of the flow combiner is about equal to an inner cross section area of any one of the tubes diverging from the common central tube. 
     
     
       18. A valving device having a linearly movable plug for selecting between a first flow path and a second flow path corresponding to a first and a second extreme positions of the linearly movable plug, and constituting a common valve, the valving device comprises a housing, the plug that is linearly movable within the housing between said first and second extreme positions, a permanently-open port common to the first flow path and the second flow path, a first port having an outer opening in fluid communication with the permanently open port when the plug is in the first of the extreme positions, a second port having fluid communication with the permanently open port when the plug is in the second of the extreme positions, wherein when the plug is in the first of the extreme positions, fluid communication between the outer opening and the permanently open port comprises a linear flow-path having a transvers transverse cross section area greater than 50% the area of the outer opening, constituting an uninterrupted bend-free flow-channel extending at least from exteriorly to the outer opening to exteriorly to the permanently-open port. 
     
     
       19. The valving device according to  claim 18 , wherein transvers transverse cross section area of the linear flow-path is greater than 75% the area of the outer opening. 
     
     
       20. The valving device according to  claim 18 , wherein the permanently-open port has a predetermined open area in a plane, parallel to a linear direction of motion of the plug, wherein the open area has a an ellipse shape having a minor axis and a major axis, the minor axis defining a width of the bidirectional permanently-open port on the plane and a the major axis defining a length of the bidirectional permanently-open port on the plane, wherein the width is smaller than the length, wherein the minor axis and correspondingly the width of the bidirectional permanently-open port on the plane is parallel or about parallel to the direction of motion of the plug. 
     
     
       21. The valving device according to  claim 18 , wherein a backwall of the plug has a protrusion fitting within a matching immovable recess, wherein the matching immovable recess extends between the second port and between a central void of the valving device, wherein said protrusion is configured to block flow of fluid from the central void to the second port when the plug is in transition between the first extreme position within the void and an intermediate position between the first extreme position and the second extreme position, wherein the first extreme position is associated with a filtration mode of operation of a self-cleaning filtration system, wherein the second extreme position is associated with a backflush mode of operation of the self-cleaning filtration system, thereby allowing to reduce evacuation of fluid during transition of the plug once configured to change a mode of operation from the filtration mode of operation to the backflush mode of operation.  
     
     
       22. The valving device according to  claim 18 , wherein the first of the extreme positions is associated with a filtration mode of operation of a self-cleaning filtration system, wherein the second of the extreme positions is associated with a backflush mode of operation of the self-cleaning filtration system, wherein the plug comprises a front protrusion configured to enter the outer opening for thereby reducing flow rate of fluid into the first port during linear motion of the plug from the first of the extreme positions to the second of the extreme positions, for at least last 30% of a full extent of a linear movability of the plug between the first and second extreme positions, whereby waste of fluid through the second port is reduced as a function of a degree of penetration of the front protrusion through the outer opening.  
     
     
       23. The valving device according to  claim 18 ,
 wherein a backwall of the plug has a protrusion substantially fitting within a matching immovable recess, wherein the matching immovable recess extends between the second port and between a central void of the valving device, wherein said protrusion is configured to block or substantially restrict flow of fluid from the central void to the second port when the plug is in transition between the first extreme position within the void and an intermediate position between the first extreme position and the second extreme position;   wherein the plug further comprises a front protrusion configured to enter the outer opening for thereby reducing flow rate of fluid into the first port during linear motion of the plug from the first extreme position to the second extreme position, for at least last 30% of a full extent of a linear movability of the plug between the first and second extreme positions; and   wherein the first extreme position is associated with a filtration mode of operation of a self-cleaning filtration system, wherein the second extreme position is associated with a backflush mode of operation of the self-cleaning filtration system, thereby allowing to reduce evacuation of fluid during transition of the plug once configured to change a mode of operation from the filtration mode of operation to the backflush mode of operation, as a function of a degree of a volume of the recess occupied by the rear protrusion and a degree of penetration of the front protrusion through the outer opening.    
     
     
       24. The valving device according to  claim 23 , wherein at least for 50% of the full extent of linear movability of the plug between the first and second extreme positions, either the rear protrusion occupies a volume of the recess or the front protrusion penetrates through the outer opening.  
     
     
       25. The valving device according to  claim 23 , wherein a distance between a frontal end of the front protrusion and a posterior end of the rear protrusion is greater than 80% a distance between a frontal end of the recess and the outer opening.  
     
     
       26. The valving device according to  claim 23 , wherein a distance between a frontal end of the front protrusion and a posterior end of the rear protrusion is equal to or greater than a distance between a frontal end of the recess and the outer opening.  
     
     
       27. The valving device according to  claim 18 , wherein the permanently open port is a bi-directional port, wherein fluid is configured to flow in a first direction with respect to the bi-directional port in the first flow path, wherein fluid is configured to flow in a second direction with respect to the bi-directional port in the second flow path, the first direction is an opposite direction to the second direction.  
     
     
       28. The filtration system according to  claim 1 , wherein the bend-free flow-channel has a cross section area perpendicularly to a longitudinal axis thereof of about 75% or more of the area of the inlet opening of the common valve.  
     
     
       29. The filtration system according to  claim 1 , wherein the bend-free flow-channel is implemented within said tube segment.  
     
     
       30. The filtration system according to  claim 1 , wherein the bend-free flow-channel provides a line of sight from the inlet opening to the filtration-element.  
     
     
       31. The filtration system according to  claim 1  having a system inlet and a system outlet, the system inlet is connected to the source of fluid to be filtered, the system outlet is connected to the filtration-chamber, the filtration system is configured to enable passage of fluid from the system inlet via the filtration-element to the system outlet, wherein the fluid to be filtered passing through the filtration system from the system inlet to the system outlet, during the filtration mode of operation, is subject to no more than three turns.  
     
     
       32. The filtration system according to  claim 1  having a system inlet, wherein the system inlet is connected to the source of fluid to be filtered, wherein the fluid to be filtered passing through the filtration system from the system inlet to filtration-chamber, during the filtration mode of operation, is subject to no more than a single turn.  
     
     
       33. The filtration system according to  claim 1  having a system outlet, the system outlet is connected to the filtration-chamber, the filtration system is configured to enable passage of fluid from the filtration-element to the system outlet, wherein fluid filtered by the filtration-element and exiting the filtration-chamber to the system outlet, during the filtration mode of operation, is subject to no more than a single turn.  
     
     
       34. The filtration system according to  claim 1 , wherein the fluid is liquid.  
     
     
       35. The filtration system according to  claim 1 , wherein in the filtration mode of operation said common valve prevents fluid communication between the evacuation opening and between both the inlet opening and the outlet opening, wherein in the backflush mode of operation said common valve prevents fluid communication between inlet opening and between both the outlet opening and the evacuation opening.  
     
     
       36. The filtration system according to  claim 1 , wherein whenever the common valve is in the filtration mode of operation, fluid provided from the source of fluid to be filtered is configured to flow through the inlet opening of said common valve to the outlet opening of said common valve, whereby the fluid to be filtered flows through the uninterrupted bend-free flow-channel to the filtration-element.  
     
     
       37. The filtration system according to  claim 1 , wherein whenever the common valve is in the backflush mode of operation, fluid from the filtration chamber is configured to flow through the outlet opening of said common valve to the evacuation opening of said common valve.  
     
     
       38. The filtration system according to  claim 1 , wherein the backflush mode of operation and the filtration mode of operation use a shared portion of said tube segment.  
     
     
       39. The filtration system according to  claim 1  comprising a filtration system member, the filtration system member comprising, in one inseparable piece, a portion of said filtration chamber, a portion of said valve housing and said tube segment connecting therebetween.  
     
     
       40. The filtration system according to  claim 39 , wherein the uninterrupted bend-free flow-channel is provided internally to said filtration system member.  
     
     
       41. The filtration system according to  claim 39 , wherein the filtration system member provides a line of sight between the inlet opening of the common valve to the outlet opening of the common valve, whereby providing the uninterrupted bend-free flow-channel.  
     
     
       42. The filtration system according to  claim 1 ,
 wherein the outlet opening is a bi-directional port;   wherein whenever the common valve is in the filtration mode of operation, fluid is configured to flow from the inlet opening of common valve to the filtration chamber via the bi-directional port, whereby causing filtration of the fluid to be filtered by the filtration-element during the filtration mode of operation; and   wherein whenever the common valve is in the backflush mode of operation, fluid is configured to flow from filtration chamber to the evacuation opening of the common valve via the bi-directional port, whereby enabling flushing of the filtration-element and evacuating dirty fluid utilized for cleaning the filtration-element.    
     
     
       43. The filtration system according to  claim 1 , wherein said tube segment having a longitudinal axis, wherein a cross-section area of the uninterrupted bend-free flow-channel that is measured transversely to the longitudinal axis and defined by parallel sightlines extending between the inlet opening and between the body of the filtration-element is 75% or more of a cross-section area of said tube segment.  
     
     
       44. A filtration system comprising:
 a filtration chamber,   a filtration-element housed within the filtration chamber, wherein the filtration-element comprises a body of the filtration-element,   a common valve comprising a valve housing in fluid communication with the filtration chamber, with a source of fluid to be filtered, and with evacuation port for backflush fluid, through three respective openings in the valve housing, the three respective openings comprise an inlet opening an outlet opening and an evacuation opening, wherein the outlet opening is permanently open,   wherein the common valve comprises a plug that is movable within a central void of the common valve between a first position and a second position, wherein the first position is associated with a filtration mode of operation of the filtration system, wherein the second position is associated with a backflush mode of operation of the filtration system,   wherein the common valve, the filtration chamber, and a tube segment connecting therebetween, are mutually configured to provide for a linear flow-channel extending from the inlet opening of the common valve to the body of the filtration-element whenever the common valve is in the filtration mode of operation, wherein the linear flow-channel provides a sightline from an outer side of the inlet opening to the filtration-element.    
     
     
       45. The filtration system according to  claim 44 , wherein the linear flow-channel has a cross section area perpendicularly to a longitudinal axis thereof of about 50% or more of the area of the inlet opening of the common valve.  
     
     
       46. The filtration system according to  claim 44 , wherein the linear flow-channel has a transvers cross section area of that is greater than 75% the area of the inlet opening of the common valve.  
     
     
       47. The filtration system according to  claim 44 ,
 wherein the plug is linearly movable within the central void of the common valve,   wherein a backwall of the plug has a protrusion substantially fitting within a matching immovable recess,   wherein the matching immovable recess extends between the evacuation opening formed in a wall of the valve housing and between the central void and has an internal free space having a predetermined volume, wherein said protrusion is configured to at least partially occupy the internal free space when the plug is in transition, between a backmost position of the plug within the void and a position closer to a foremost position of the plug within the void until full departure of the protrusion out from within the immovable recess, thereby reducing evacuation of fluid through the immovable recess during transition of the plug between a filtration mode of operation and a backflush mode of operation as a function of a degree of a volume of the recess, occupied by the rear protrusion.    
     
     
       48. The filtration system according to  claim 44 , wherein the common valve comprises a plug is linearly movable between the first position and the second position.  
     
     
       49. The filtration system according to  claim 48 , wherein the plug comprises a rear protrusion configured to restrict fluid passage from the central void of the valve to the evacuation opening during linear motion of the plug from the first position to the second position, wherein at least a portion of a predetermined volume of the recess is occupied by the rear protrusion for at least first 30% of full extent of the linear motion whereby waste of fluid through the evacuation port is reduced as a function of a degree of a volume of the recess occupied by the rear protrusion.  
     
     
       50. The filtration system according to  claim 49 , wherein the rear protrusion is cylindrical, a height of which is oriented parallel to a direction of the linear motion.  
     
     
       51. The filtration system according to  claim 44 , wherein the plug that is linearly movable between the first position and the second position, wherein the plug comprises a front protrusion configured to enter the inlet opening for thereby reducing a flow rate of fluid into the inlet opening during linear motion of the plug from the first position to the second position, wherein at least a portion of the front protrusion penetrates through the inlet opening for at least last 30% of full extent of the linear motion, whereby waste of fluid through the evacuation port is reduced as a function of a degree of penetration of the front protrusion through the inlet opening.  
     
     
       52. The filtration system according to  claim 51 , wherein the front protrusion is conically like, tapering towards the inlet opening.  
     
     
       53. The filtration system according to  claim 44 , wherein an angle between a longitudinal axis of the tube segment and a longitudinal axis of the filtration chamber is between 35 and 55 degrees.  
     
     
       54. The filtration system according to  claim 44 , wherein the tube segment has an elliptically shaped cross section perpendicularly to its longitudinal axis, flattened in a direction parallel to the direction of linear motion, thereby allowing for a shortening the extent of linear motion of the plug per a given cross section area of the tube segment.  
     
     
       55. The filtration system according to  claim 44 , wherein a proximal end of the filtration chamber, at least most of the housing of the common valve and the tube segment are inseparable members of a single piece of material.  
     
     
       56. The filtration system according to  claim 44 , wherein the outlet opening of the common valve has a predetermined open area in a plane, parallel to a linear direction of motion of the plug, wherein the open area has a minor axis defining a width of the outlet opening of the common valve on the plane and a major axis defining a length of the outlet opening of the common valve on the plane, wherein the width is smaller than the length, wherein the minor axis and correspondingly the width of the outlet opening on the plane is parallel or closely parallel to the direction of motion of the plug.  
     
     
       57. A twin filtration system comprising a first and a second filtration systems, each according to  claim 44 , said first and second filtration systems are connected together in mirroring configuration, wherein the twin filtration system comprises a flow splitter and a flow combiner, the flow splitter connects a fluid inlet of the twin filtration system with the inlet opening of the common valve in the first system and the inlet opening of the common valve in the second system, the flow combiner connects an outlet opening of the filtration chamber in the first system and an outlet opening of the filtration chamber in the second system with an outlet of the twin filtration system.  
     
     
       58. A twin filtration system according to  claim 57 , wherein the flow splitter comprises a pair of arched tubes diverging from a first central common tube, wherein the flow combiner comprises a pair of arched tubes diverging from a second central common tube.  
     
     
       59. The twin filtration system according to  claim 58 , wherein a radius of a largest inner curve of each of the arched tubes is between about 100% and 150% the diameter of the respective central common tube.  
     
     
       60. The twin filtration system according to  claim 57 , wherein an inner cross section area of a respective central common tube of the flow splitter or the flow combiner is closely equal to an inner cross section area of any one of the tubes diverging from the respective common central tube.  
     
     
       61. A filtration system member, comprising in one inseparable piece a portion of filtration chamber housing, a portion of a housing of a common valve located exteriorly to and remotely from the portion of filtration-chamber housing, and a tube segment connecting therebetween, wherein the portion of filtration chamber housing, the portion of a housing of the common valve, and the tube segment, are mutually configured to provide for a linear flow-channel extending at least from an inlet opening of the common valve, to interiorly of the portion of filtration chamber housing, wherein the linear flow-channel provides a sightline from an outer side of the inlet opening of the common valve to an interior of the portion of filtration chamber housing, wherein the common valve comprises a plug that is linearly moveable between a first position and a second position within the housing of the common valve.  
     
     
       62. A filtration system member, comprising in one inseparable piece a portion of filtration chamber housing, a portion of a housing of a common valve located exteriorly to and remotely from the portion of filtration-chamber housing, and a tube segment connecting therebetween, wherein the portion of filtration chamber housing, the portion of a housing of the common valve, and the tube segment, are mutually configured to provide for a linear flow-channel extending at least from an inlet opening of the common valve, to interiorly of the portion of filtration chamber housing, wherein the linear flow-channel provides a sightline from an outer side of the inlet opening of the common valve to an interior of the portion of filtration chamber housing, wherein said filtration system member is being part of a filtration system, the filtration system comprises a filtration element, the filtration element is housed, at least partially, within the portion of filtration chamber housing, wherein the linear flow-channel provides a sightline from the outer side of the inlet opening of the common valve to the filtration element.