초록 ▼

A constant flow regulating valve of the type described in U.S. Pat. Nos. 6,026,850 and 6,209,578 includes a closure mechanism configured and arranged to override the modulating mode of the valve and to close the valve at fluid inlet pressures both below and above the valve's threshold level. The clo

A constant flow regulating valve of the type described in U.S. Pat. Nos. 6,026,850 and 6,209,578 includes a closure mechanism configured and arranged to override the modulating mode of the valve and to close the valve at fluid inlet pressures both below and above the valve's threshold level. The closure mechanism may be selectively deactivated to thereby allow the valve to assume its normal pressure responsive regulating functions. Embodiments of the regulating valve incorporate pressure relief devices and vent seals, with configurations suitable for incorporation into the trigger assemblies of portable sprayers.

대표청구항 ▼

What is claimed is: 1. A regulating valve for receiving fluid at a variable inlet pressure from a fluid source and for delivering said fluid at a substantially constant outlet pressure and flow rate to a fluid applicator or the like, said valve comprising: a housing internally subdivided by a barri

What is claimed is: 1. A regulating valve for receiving fluid at a variable inlet pressure from a fluid source and for delivering said fluid at a substantially constant outlet pressure and flow rate to a fluid applicator or the like, said valve comprising: a housing internally subdivided by a barrier wall into a head section and a base section; a port in said barrier wall; a modulating assembly internally subdividing said base section into a fluid chamber and a spring chamber, said modulating assembly having a stem projecting along an axis through said port into said head section, and having a flexible diaphragm supporting said modulating assembly for movement in opposite directions along said axis; an inlet in said housing for connecting said head section to said fluid source; an outlet in said housing communicating with said fluid chamber; a spring in said spring chamber, said spring being responsive to inlet pressures below a threshold level to maintain said modulating assembly against said barrier wall and to thereby prevent fluid through flow from said head section via said port and fluid chamber to said outlet, said spring being yieldably responsive to inlet pressures above said threshold level to thereby accommodate movement of said modulating assembly away from said barrier wall, with an accompanying fluid through flow from said head section via said port and said fluid chamber to said outlet, and with said stem serving to modulate the size of the flow path through said port as an inverse function of variations in said inlet pressure above said threshold level, whereby said outlet pressure and flow rate is maintained at a substantially constant level; closure means acting independently of said spring, said closure means comprising a rod axially movable between a holding position in contact with and maintaining said modulating assembly against said barrier wall when said inlet pressure is both above and below said threshold level, and a deactivated position spaced from said modulating assembly; and operating means for selectively deactivating said closure means. 2. The regulating valve of claim 1 wherein said rod is aligned with and axially movable along said axis. 3. The regulating valve of claim 1 or 2 wherein said rod is resiliently maintained in said holding position by a second spring having a closure force exceeding the closure force of said first mentioned spring. 4. The regulating valve of claim 3 wherein said operating means comprises a manually operable lever operatively connected to said rod. 5. The regulating valve of claim 3 wherein said operating means comprises a solenoid. 6. The regulating valve of claim 1 wherein said closure means comprises a second spring having a closure force that exceeds the closure force of said first mentioned spring. 7. The regulating valve of claim 1 wherein said fluid source is a portable sprayer, and wherein said outlet is connected to a wand leading to a nozzle. 8. The regulating valve of claim 7 wherein said portable sprayer is a knapsack sprayer. 9. The regulating valve of claim 7 wherein said portable sprayer is a compression sprayer. 10. The regulating valve of claim 1 or 7 further comprising pressure relief means for bleeding liquid from said head section into said fluid chamber. 11. The regulating valve of claim 10 wherein said pressure relief means comprises a vent path extending from an entry opening communicating with said head section to an exit opening communicating with said fluid chamber, a pin having a closure head in said head section and an operating head located externally of said housing, and a spring for biasing said pin into a closed position at which said closure head closes said entry opening and prevents the passage of liquid from said head section via said vent path to said fluid chamber, said operating head being depressible to overcome the biasing force of said spring to thereby permit liquid to flow from said head section via said vent path to said fluid chamber. 12. The regulating valve of claim 1 wherein said housing comprises a cap and a cup-shaped base, said barrier wall and said modulating assembly being preassembled to form a first subassembly received in said cap, and said cup-shaped base and said spring and closure means being preassembled to form a second subassembly received in and operatively coupled to said cap. 13. The regulating valve of claim 12, wherein said second subassembly is operatively coupled by snap engagement of said cup-shaped base with said cap. 14. The regulating valve of claim 13 wherein said snap engagement results from rotation of said cup-shaped base relative to said cap. 15. The regulating valve of claim 1 further comprising a vent opening in said housing in communication with said spring chamber. 16. The regulating valve of claim 15 further comprising a seal for said vent opening, said seal being adapted to accommodate passage of gas through said vent opening and to prevent the passage of liquid through said vent opening. 17. The regulating valve of claim 16 wherein said seal comprises a gas permeable hydrophobic membrane. 18. The regulating valve of claim 16 wherein said seal comprises a hydrophobic bushing inserted in said vent opening, said bushing defining a restricted vent passageway that is closed in response to the absorption of liquid by said bushing. 19. The regulating valve of claim 16 wherein said seal comprises a flexible diaphragm imperious to both liquids and gases. 20. A regulating valve for receiving fluid at a variable inlet pressure from a fluid source and for delivering said fluid at a substantially constant outlet pressure and flow rate to a fluid applicator or the like, said valve comprising: a housing internally subdivided by a barrier wall into a head section and a base section; a port in said barrier wall; a modulating assembly internally subdividing said base section into a fluid chamber and a spring chamber, said modulating assembly having a stem projecting along an axis through said port into said head section, and having a flexible diaphragm supporting said modulating assembly for movement in opposite directions along said axis; an inlet in said housing for connecting said head section to said fluid source; an outlet in said housing communicating with said fluid chamber; a spring in said spring chamber, said spring being responsive to inlet pressures below a threshold level to maintain said modulating assembly against said barrier wall and to thereby prevent fluid through flow from said head section via said port and fluid chamber to said outlet, said spring being yieldably responsive to inlet pressures above said threshold level to thereby accommodate movement of said modulating assembly away from said barrier wall, with an accompanying fluid through flow from said head section via said port and said fluid chamber to said outlet, and with said stem serving to modulate the size of the flow path through said port as an inverse function of variations in said inlet pressure above said threshold level, whereby said outlet pressure and flow rate is maintained at a substantially constant level, and wherein said housing comprises a cap and a cup-shaped base, said barrier wall and said modulating assembly comprises a first preassembled subassembly adapted to be received in said cap, and said cup-shaped base and said spring comprise a second preassembled subassembly adapted to be received in and operatively coupled to said cap. 21. The regulating valve of claim 20 further comprising closure means acting independently of said spring for maintaining said modulating assembly against said barrier wall when said inlet pressure is both above and below said threshold level, and operating means for selectively activating said closure means.