# US 2014/0150893 A1 · Shutoff valve in backflow prevention device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0150893 A1 - Document ID: US20140150893A1 - Status: Published application - Kind: A1 - Application number: 13/705,033 - Filed: 2012-12-04 - Published: 2014-06-05 - Earliest claimed: 2012-12-04 - Inventors: Douglas Hunter Powell - Web page: https://patentgrep.com/patent/US20140150893A1 ## CPC - F16K 15/182: {with actuating mechanism} - F16K 15/033: {spring-loaded} - F16K 15/035: {with a plurality of valve members} - Y10T 137/3294: Valved - Y10T 137/7838: Plural - Y10T 137/7898: Pivoted valves - Y10T 137/87917: Flow path with serial valves and/or closures - F16K: VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING {(devices for emptying and evacuating the excess liquid in valves or conduits F16L55/07)} - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A backflow prevention device including an upstream shutoff valve configured to allow a user to control the water flow stream through the housing. The upstream shutoff valve includes an obstruction. The obstruction is configured to prevent water flow at a first position and allow water flow at a second position. The obstruction is also configured to rotate about an axis of rotation between the first position and the second position. The upstream shutoff valve also includes a seal. The seal is configured to sealingly engage a sealing surface in the housing at the first position. All points of engagement between the obstruction seal and the sealing surface are located downstream of the axis of rotation of the obstruction. ## Claims ### Claim 1 A backflow prevention device, the backflow prevention device comprising: a housing defining a water flow stream; an upstream shutoff valve, wherein the upstream shutoff valve: is configured to allow a user to control the water flow stream through the housing; and includes an obstruction, wherein the obstruction: is configured to: prevent water flow at a first position; allow water flow at a second position; and rotate about an axis of rotation between the first position and the second position; and includes a seal, wherein the seal is: configured to sealingly engage a sealing surface in the housing at the first position; and wherein all points of engagement between the obstruction seal and the sealing surface are located downstream of the axis of rotation of the obstruction; an upstream check valve: located within the housing downstream of the upstream shutoff valve; and including: an orifice, wherein the orifice is configured to allow the water flow stream through the upstream check valve; and a clapper, wherein the clapper is configured to: allow the water flow stream through the orifice when open; and prevent the water flow stream through the orifice when in a closed position by mating with the orifice; a downstream check valve: located within the housing downstream of the upstream check valve; and including: an orifice, wherein the orifice is configured to allow the water flow stream through the downstream check valve; a clapper, wherein the clapper is configured to: allow the water flow stream through the orifice when open; and prevent the water flow stream through the orifice when in a closed position by mating with the orifice; and a downstream shutoff valve, wherein the downstream shutoff valve is configured to allow a user to control the water flow stream through the housing. ### Claim 2 (depends on 1) The backflow prevention device of claim 1 further comprising: a first elastomer disk in the clapper of the upstream check valve, the first elastomer disk sealing the mating of the clapper with the orifice; and a second elastomer disk in the clapper of the downstream check valve, the second elastomer disk sealing the mating of the clapper with the orifice. ### Claim 3 (depends on 4) The backflow prevention device of claim 4 further comprising: a first lip located on the outer edge of the orifice of the upstream check valve configured to sealingly engage the first elastomer disk; and a second lip located on the outer edge of the orifice of the downstream check valve configured to sealingly engage the second elastomer disk. ### Claim 4 (depends on 1) The backflow prevention device of claim 1 further comprising a relief valve, wherein the relief valve is configured to operate based upon the pressure differential between: the volume between the upstream shutoff valve and the upstream check valve; and the volume between the upstream check valve and the downstream check valve. ### Claim 5 (depends on 1) The backflow prevention device of claim 1 further comprising: a first bias configured to hold the clapper of the upstream check valve in the closed position unless a predetermined upstream pressure exists; and a second bias configured to hold the clapper of the downstream check valve in the closed position unless a predetermined downstream pressure exists. ### Claim 6 (depends on 1) The backflow prevention device of claim 1, wherein: the first bias includes a first spring; and the second bias includes a second spring. ### Claim 7 (depends on 1) The backflow prevention device of claim 1 further comprising a check retainer configured to maintain a minimum distance between the upstream check valve and the downstream check valve. ### Claim 8 (depends on 1) The backflow prevention device of claim 1 further comprising an upstream control configured to allow a user to control the position of the upstream shutoff valve. ### Claim 9 (depends on 1) The backflow prevention device of claim 1 further comprising an upstream sensor configured to trigger an alarm when the upstream shutoff valve is in the first position. ### Claim 10 (depends on 1) The backflow prevention device of claim 1 further comprising: an opening configured to allow a user to remove either of the upstream check valve and the downstream check valve. ### Claim 11 A backflow prevention device, the backflow prevention device comprising: a housing defining a water flow stream; an upstream shutoff valve, wherein the upstream shutoff valve: is configured to allow a user to control the water flow stream through the housing; and includes a disk, wherein the disk: is configured to: prevent water flow at a first position; allow water flow at a second position; and rotate about an axis of rotation between the first position and the second position; and includes a seal, wherein the seal is: configured to sealingly engage a sealing surface in the housing at the first position; and wherein all points of engagement between the disk seal and the sealing surface are located downstream of the axis of rotation of the disk; an upstream check valve: located within the housing downstream of the upstream shutoff valve; and including: a seat configured to mate with a portion of the housing; an orifice, wherein the orifice is configured to allow the water flow stream through the upstream check valve; and a clapper, wherein the clapper is configured to: allow the water flow stream through the orifice when open; and prevent the water flow stream through the orifice when in a closed position by mating with the orifice; a downstream check valve: located within the housing downstream of the upstream check valve; and including: a seat configured to mate with a portion of the housing; an orifice, wherein the orifice is configured to allow the water flow stream through the downstream check valve; a clapper, wherein the clapper is configured to: allow the water flow stream through the orifice when open; and prevent the water flow stream through the orifice when in a closed position by mating with the orifice; and a downstream shutoff valve, wherein the downstream shutoff valve is configured to allow a user to control the water flow stream through the housing. ### Claim 12 (depends on 19) The backflow prevention device of claim 19, wherein the first sealing surface includes a curved surface equivalent to a spherical segment. ### Claim 13 (depends on 11) The backflow prevention device of claim 11, wherein the seal of the upstream shutoff valve includes an O-ring. ### Claim 14 A backflow prevention device, the backflow prevention device comprising: a housing defining a water flow stream; an upstream shutoff valve, wherein the upstream shutoff valve: is configured to allow a user to control the water flow stream through the housing; and includes a disk, wherein the disk: is configured to: prevent water flow at a first position; allow water flow at a second position; and rotate about an axis of rotation between the first position and the second position; and includes a spherical segment, wherein the spherical segment includes the spherical segment of a sphere with a diameter that is concurrent with an axis with the shaft of the upstream shutoff valve; and includes a seal, wherein the seal is: configured to sealingly engage a sealing surface in the housing at the first position; and wherein all points of engagement between the disk seal and the sealing surface are located downstream of the axis of rotation of the disk; an upstream check valve: located within the housing downstream of the upstream shutoff valve; and including: a seat configured to mate with a portion of the housing; an orifice, wherein the orifice is configured to allow the water flow stream through the upstream check valve; and a clapper, wherein the clapper is configured to: allow the water flow stream through the orifice when open; and prevent the water flow stream through the orifice when in a closed position by mating with the orifice; a downstream check valve: located within the housing downstream of the upstream check valve; and including: a seat configured to mate with a portion of the housing; an orifice, wherein the orifice is configured to allow the water flow stream through the downstream check valve; a clapper, wherein the clapper is configured to: allow the water flow stream through the orifice when open; and prevent the water flow stream through the orifice when in a closed position by mating with the orifice; and a downstream shutoff valve, wherein the downstream shutoff valve is configured to allow a user to control the water flow stream through the housing. ### Claim 15 (depends on 14) The backflow prevention device of claim 14 further comprising: a first sensing port configured to provide access through the housing to the volume upstream of the upstream shutoff valve; a second sensing port configured to provide access through the housing to the volume between the upstream shutoff valve and the upstream check valve; a third sensing port configured to provide access through the housing to the volume between the upstream check valve and the downstream check valve; and a fourth sensing port configured to provide access through the housing to the volume between the downstream check valve and the downstream shutoff valve. ### Claim 16 (depends on 14) The backflow prevention device of claim 14 further comprising rotating means configured to allow a user to rotate the disk of the upstream shutoff valve between the first position and the second position. ### Claim 17 (depends on 16) The backflow prevention device of claim 16, wherein the rotating means includes a shaft. ### Claim 18 (depends on 17) The backflow prevention device of claim 17, wherein the disk of the upstream shutoff valve includes a spherical segment; and ### Claim 19 (depends on 18) The backflow prevention device of claim 18, wherein the spherical segment of the disk of the upstream shutoff valve includes the spherical segment of a sphere with a diameter that is concurrent with an axis with the shaft of the upstream shutoff valve.