초록 ▼

The present flow shutoff valve comprises a flow metering sleeve positioned within a flow passage. The sleeve and a housing of the valve define an annular space. The sleeve includes a flow metering aperture downstream of the annular space. A valve member is slidably mounted within the sleeve. The val

The present flow shutoff valve comprises a flow metering sleeve positioned within a flow passage. The sleeve and a housing of the valve define an annular space. The sleeve includes a flow metering aperture downstream of the annular space. A valve member is slidably mounted within the sleeve. The valve member is movable between a no flow position, a normal flow position and a shutoff position. The valve is self cleaning, so that it reduces the buildup of sediment within the valve.

대표청구항 ▼

What is claimed is: 1. A self cleaning flow shutoff valve configured to be installed in a water line to stop flow in response to an excess water flow condition, the valve comprising: a housing defining a flow passage and a valve seat; a flow-metering element positioned within the flow passage, the

What is claimed is: 1. A self cleaning flow shutoff valve configured to be installed in a water line to stop flow in response to an excess water flow condition, the valve comprising: a housing defining a flow passage and a valve seat; a flow-metering element positioned within the flow passage, the flow-metering element including a flow metering aperture on a downstream portion thereof, the flow metering aperture providing fluid communication through a body wall of the element; a valve member slidably mounted within the flow-metering element, the valve member being movable between a no flow position, a normal flow position and a shutoff position, a downstream end of the valve member including a sealing portion configured to selectively engage the valve seat; and a biasing element disposed between the housing and the valve member so as to bias the valve member away from the valve seat; wherein (a) when the valve member is in the no flow position, an upstream end of the valve member engages the housing adjacent an inlet end of the housing, the sealing portion is spaced from the valve seat, and the valve member does not cover the flow metering aperture; (b) when the valve member is in the normal flow position, the upstream end of the valve member is spaced from the housing, the sealing portion is spaced from the valve seat, and the valve member does not cover the flow metering aperture; and (c) when the valve member is in the shutoff position, the upstream end of the valve member is spaced from the housing, the sealing portion engages the valve seat, and the valve member covers the flow metering aperture. 2. The flow shutoff valve of claim 1, wherein the housing comprises an upstream section and a downstream section. 3. The flow shutoff valve of claim 2, wherein the upstream and downstream sections are separate components that adjoin one another. 4. The flow shutoff valve of claim 1, wherein a portion of the housing located downstream from the valve member defines the valve seat. 5. The flow shutoff valve of claim 1, wherein the flow-metering element includes a cylindrical section and a cap section at a downstream end of the cylindrical section. 6. The flow shutoff valve of claim 5, wherein the flow metering aperture is located adjacent to and upstream from the cap section. 7. The flow shutoff valve of claim 5, wherein the cap section includes a chamfer about its downstream, outer edge. 8. The flow shutoff valve of claim 7, further comprising a sealing element positioned between the chamfer and the housing. 9. The flow shutoff valve of claim 1, wherein the valve member sealing portion comprises a resilient O-ring seal. 10. The flow shutoff valve of claim 1, further comprising a plurality of flow metering apertures extending through the flow-metering element body wall. 11. The flow shutoff valve of claim 1, wherein when the valve member is in the normal flow position water flows past the upstream end of the valve member, then through an annular space defined between an inner surface of the housing and an outer surface of the flow-metering element, then through the flow metering aperture and around a downstream end of the valve member and then past the valve seat. 12. The flow shutoff valve of claim 1 in combination with a hose, the flow shutoff valve being integrated into an inlet end of the hose. 13. The flow shutoff valve/hose combination of claim 12, further comprising a flow restricting orifice at an outlet end of the hose. 14. A method of stopping flow in a water line in response to an excess water flow condition, the method comprising the steps of: beginning with a flow shutoff valve in the water line in a no flow position in which an upstream end of a valve member engages a housing of the valve adjacent an inlet end of the housing, a sealing portion of the valve member is spaced from a valve seat located downstream of the valve member, and the valve member does not cover the flow metering aperture; creating a differential pressure across the valve member in which a downstream water pressure is less than an upstream water pressure to move the valve member to a normal flow position in which the upstream end of the valve member is spaced from the housing, the sealing portion is spaced from the valve seat, and the valve member does not cover the flow metering aperture; and increasing a water flow rate across the valve member above a threshold flow rate to move the valve member to a shutoff position in which the upstream end of the valve member is spaced from the housing, the sealing portion engages the valve seat, and the valve member covers the flow metering aperture; wherein, when the valve member is in the normal flow position, water flows past the upstream end of the valve member, then through an annular space defined between an inner surface of the housing and an outer surface of the flow-metering element, then through the flow metering aperture and around a downstream end of the valve member and then past the valve seat. 15. The method of claim 14, wherein when the valve member moves from the no flow position to the normal flow position movement of the valve element and a sudden surge of water through the valve purges sediment from the valve. 16. The method of claim 14, wherein the housing comprises an upstream section and a downstream section formed as separate components that adjoin one another. 17. The method of claim 14, wherein a portion of the housing located downstream from the valve member defines the valve seat. 18. The method of claim 14, wherein the flow-metering element includes a cylindrical section and a cap section at a downstream end of the cylindrical section. 19. The method of claim 18, wherein the flow metering aperture is located adjacent to and upstream from the cap section. 20. The method of claim 18, wherein the cap section includes a chamfer about its downstream, outer edge. 21. The method of claim 20, further comprising a sealing element positioned between the chamfer and the housing. 22. The method of claim 14, wherein the valve member sealing portion comprises a resilient O-ring seal.