# US 10,373,471 B2 · Leak detector > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,373,471 B2 - Document ID: US10373471B2 - Status: Granted - Kind: B2 - Application number: 16/152,873 - Filed: 2018-10-05 - Published: 2019-01-31 - Granted: 2019-08-06 - Earliest claimed: 2016-03-22 - Assignees: Watts Regulator Co. - Applicants: Watts Regulator Co. - Inventors: Jason W Doughty; Peter P Bouchard; Paul J Lake; Joseph M Burke - Web page: https://patentgrep.com/patent/US10373471B2 ## CPC - G08B 21/12: responsive to undesired emission of substances, e.g. pollution alarms - E03B 7/077: {Arrangement of backflow preventing devices} - E03B 7/078: {Combined units with different devices; Arrangement of different devices with respect to each other} - G01F 1/28: by drag-force, e.g. vane type or impact flowmeter - G01F 1/56: by using electric or magnetic effects (G01F1/66 takes precedence) - G01M 3/16: using electric detection means ({G01M3/045,} G01M3/06, G01M3/12, G01M3/20, G01M3/24, G01M3/26 take precedence) - G01M 3/184: {for valves} - G01M 3/3254: {using a flow detector (G01M3/3245, G01M3/3272 take precedence)} - G08B 21/182: {Level alarms, e.g. alarms responsive to variables exceeding a threshold} - G08B: SIGNALLING SYSTEMS, e.g. PERSONAL CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS - E03B: INSTALLATIONS OR METHODS FOR OBTAINING, COLLECTING, OR DISTRIBUTING WATER (drilling wells, obtaining fluids in general from wells E21B; pipe-line systems in general F17D) - G01F: MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR ## Abstract A leak detector assembly for use with a backflow prevention device includes a housing defining a passageway for receiving a fluid. A flap assembly couples to the housing for generating a low flow error signal indicating minimal fluid passing through the passageway and a fully actuated error signal indicating significant fluid passing through the passageway. The flap assembly includes a flap mounted in the passageway such that significant flow of the fluid moves the flap to generate the fully actuated error signal. The flap assembly also includes a sensing element on the flap to determine a presence of the fluid without movement of the flap to generate the low flow error signal based on a low flow of the fluid. ## Claims ### Claim 1 A backflow prevention assembly comprising: a backflow prevention device for preventing cross-contamination between an upstream potable water source and a downstream non-potable water source by discharging backflow to a drain; and a leak detector assembly coupled to the backflow prevention device before the drain for sensing the discharged backflow from the backflow prevention device, wherein the leak detector assembly includes: a housing defining a passageway for receiving the discharged backflow; and a flap assembly coupled to the housing, the flap assembly including a sensing element on a flap to determine a presence of the discharged backflow without movement of the flap to generate a low flow error signal based on a low flow of the discharged backflow and the flap is mounted in the passageway such that when flow of the discharged backflow moves the flap a certain required distance, the leak detector assembly generates a high flow error signal. ### Claim 2 (depends on 1) The backflow prevention assembly as recited in claim 1, wherein the backflow prevention device is selected from the group consisting of: a pressure vacuum breaker (PVB); a reduced pressure zone (RPZ); a double check assembly (DCA); and an atmospheric vacuum breaker (AVB). ### Claim 3 (depends on 1) The backflow prevention assembly as recited in claim 1, further comprising an application specific printed circuit board for receiving at least one signal from the leak detector assembly, determining a comparison of the at least one signal to a predetermined threshold, and generating an alarm based upon the comparison. ### Claim 4 (depends on 1) The backflow prevention assembly as recited in claim 1, wherein absorptive material on the flap raises a minimum drip requirement to generate the low flow error signal. ### Claim 5 (depends on 1) The backflow prevention assembly as recited in claim 1, wherein the flap is angled with respect to a direction of water flow through the passageway to shed drips effectively so that moisture does not puddle on the flap. ### Claim 6 (depends on 5) The backflow prevention assembly as recited in claim 5, wherein the passageway is vertical and the flap is at a 45° angle with respect to the passageway. ### Claim 7 (depends on 1) The backflow prevention assembly as recited in claim 1, further comprising a main controller for receiving the low flow error signal, the high flow error signal, and a normal flow signal from the leak detector assembly, wherein the normal flow signal indicates no backflow is present in the passageway. ### Claim 8 (depends on 7) The backflow prevention assembly as recited in claim 7, wherein the main controller stores data based on the low flow error signal, the high flow error signal, and the normal flow signal to determine if maintenance is needed. ### Claim 9 (depends on 1) The backflow prevention assembly as recited in claim 1, further comprising energy disbursing means for disbursing energy of the discharged backflow prior to contact with the sensing element of the leak detector assembly. ### Claim 10 (depends on 9) The backflow prevention assembly as recited in claim 9, wherein the energy disbursing means is selected from the group consisting of a screen and a shower head device. ### Claim 11 A backflow prevention assembly comprising: a backflow prevention device; a leak detector assembly coupled to the backflow prevention device having a first sensor for sensing discharge from the backflow prevention device to generate leak signal; and a printed circuit board for: receiving the leak signal from the leak detector assembly; determining a comparison of the at least one signal to a predetermined threshold; and generating a first alarm based upon the comparison, wherein: the first sensor does not require movement to generate the leak signal; the first alarm is a low flow error signal for tracking by maintenance personnel; and the leak detector assembly includes: a housing defining a passageway for receiving a fluid; and a flap assembly coupled to the housing, the flap assembly including a flap mounted in the passageway such that when flow of the fluid moves the flap, a second sensor is activated by flap movement to generate a second alarm, which is a high flow error signal generated by the printed circuit board indicating immediate attention is required by the maintenance personnel. ### Claim 12 (depends on 11) The backflow prevention assembly as recited in claim 11, wherein the flap assembly includes: a magnet coupled to the flap for rotation therewith; and a fixed magnetic sensor such that the high flow error signal is generated based upon the magnet moving away from the fixed magnetic sensor. ### Claim 13 (depends on 12) The backflow prevention assembly as recited in claim 12, wherein one of the magnet and the fixed magnetic sensor is mechanically adjustable to adjust a set point for the high flow error signal. ### Claim 14 A backflow prevention assembly comprising: a backflow prevention device for preventing cross-contamination between an upstream potable water source and a downstream non-potable water source by discharging backflow to a drain; and a leak detector assembly coupled to the backflow prevention device before the drain for sensing the discharged backflow from the backflow prevention device, the leak detector assembly including: a housing defining a passageway for the discharged backflow; and a flap assembly coupled to the housing, wherein the flap assembly includes: a flap mounted in the passageway such that when flow of the discharged backflow moves the flap to open the passageway, the leak detector assembly generates a high flow error signal; and a sensing element on the flap to determine a presence of the discharged backflow without movement of the flap to generate a low flow error signal based on a low flow of the discharged backflow with the flap having a normal position at an angle with respect to a direction of flow of the discharged backflow for preventing puddling of the discharged backflow on the flap. ### Claim 15 (depends on 14) The backflow prevention assembly of claim 14, wherein the direction of flow of the discharged backflow is vertical passageway. ### Claim 16 (depends on 14) The backflow prevention assembly of claim 14, further comprising a screen for disbursing energy of the discharged backflow prior to contact with the flap. ### Claim 17 (depends on 14) The backflow prevention assembly of claim 14, further comprising absorptive material on the flap. ### Claim 18 A backflow prevention assembly comprising: a backflow prevention device for preventing cross-contamination between an upstream potable water source and a downstream non-potable water urce by discharging backflow to a drain; a leak detector assembly coupled to the backflow prevention device before the drain for sensing the discharged backflow from the backflow prevention device, wherein the leak detector assembly includes: a housing defining a passageway for receiving the discharged backflow; and a flap assembly coupled to the housing, the flap assembly including a sensing element on a flap to determine a presence of the discharged backflow without movement of the flap to generate a low flow error signal based on a low flow of the discharged backflow; and a screen for disbursing energy of the discharged backflow prior to contact with the flap.