Self-cleaning filter assembly for solenoid-actuated valve

A solenoid-actuated valve comprising:

• a valve housing having an inlet chamber and an outlet chamber;
• a valve member disposed between said inlet and outlet chambers and movable between open and closed positions whereby fluid in said inlet chamber respectively communicates with said outlet chamber or is blocked from said outlet chamber;
• a pressure-operated diaphragm coupled with said valve member and operable to move said valve member between said open position and said closed position;
• a control chamber in fluid pressure communication with said diaphragm and adapted to receive pressurized fluid therein;
• passageway means for admitting fluid from said inlet chamber to said control chamber;
• a solenoid for controlling the pressure of fluid in said control chamber, said solenoid in one condition permitting said pressure in said control chamber to substantially equal the fluid pressure in said inlet chamber and to act on said diaphragm to hold said valve member in said closed position, and in another condition relieving said pressure in said control chamber sufficiently to permit movement to said diaphragm to open said valve member;
• and
• a self-cleaning filter assembly disposed in said inlet chamber for filtering said fluid admitted to said control chamber through said passageway means, said assembly comprising a filter element for filtering said fluid and a cleaning element including at least one scraper blade and scraper blade arm having sufficient deflection for biasing said at least one scraper blade into scraping engagement with said filter element, said cleaning element, and said filter element being movable one relative to the other, and one of said cleaning element and said filter element being coupled for movement with said valve member so that said scraper blade scrapes said filter element each time said valve member moves between the open and closed positions.

In a valve having an inlet chamber, an outlet chamber, a valve member movable to open and close fluid flow between said inlet and outlet chambers, a diaphragm carrying said valve member and responsive to fluid pressure in a control chamber for movably positioning said valve member between open and closed fluid flow positions, and pilot means for controlling fluid pressure within said control chamber, said pilot means including passage means for bleeding a portion of the fluid at said inlet chamber to said control chamber, a self-cleaning filter assembly, comprising:

• a filter element mounted within said inlet chamber for passage of the portion of the fluid thereof to said passage means;
• and
• a cleaning element substantially surrounding said filter element and including at least one scraper blade in scraping engagement with said filter element, and scraper blade arm having sufficient deflection for urging and maintaining said at least one scraper blade in scraping engagement with said filter element;
• said cleaning element and said filter element being movable relative to each other, one of said cleaning element and said filter element being mounted for movement with said valve member to translate said filter element and said at least one scraper blade with respect to each other whereby said scraper blade removes accumulated filtered matter from said filter element.

In a valve including an inlet chamber, an outlet chamber, a valve member movable to open and close fluid flow between said inlet and outlet chambers, a control chamber, pivot valve means for controlling the fluid pressure within said control chamber, said pilot valve means including passage means for bleeding a portion of fluid at the inlet chamber to said control chamber, a filter assembly for filtering the portion of fluid flowing into said passage means, comprising:

• a filter element mounted within said inlet chamber for passage of the portion of the fluid thereof to said passage means;
• and
• a cleaning element substantially surrounding said filter element and including a plurality of scraper blades each in scraping engagement with said filter element and together substantially surrounding said filter element, and a corresponding plurality of scraper blade arms having sufficient deflection for urging and maintaining respective ones of said scraper blades in scraping engagement with said filter element;
• said cleaning element and said filter element being movable relative to each other, one of said cleaning element and said filter element being mounted for movement with said valve member to translate said filter element and said scraper blades with respect to each other whereby said scraper blades remove accumulated filtered matter from said filter element.