The subject disclosure relates to backflow prevention valves and assemblies, and more particularly to a device for continuously monitoring the status of the backflow prevention system.
In many water systems, a backflow prevention valve and assembly, sometimes referred to as a backflow preventer (BFP), assures that a fluid, and any solids therein, flows in only a desired direction, i.e., a forward direction. As backsiphonage, or backflow, may cause contamination and health problems, a BFP prevents flow in an undesired direction, i.e., a backward or reverse direction. For example, backflow prevention valves and assemblies are installed in buildings, such as residential homes, and commercial buildings and factories, to protect public water supplies by preventing the reverse flow of contaminated water back into the public water supply.
Referring now to
Owing to the fact that backflow preventers (BFPs) are important for water safety, they are manually tested on an annual basis to assure proper operating condition. Specifically, fluid pressure measurements are taken at specified locations in the BFP 100. To facilitate these pressure measurements, the BFP 100 includes a number of Test Cocks (TCs) 102a-102d (generally 102), each of which includes a ball valve, where the TC 102 is threadably connected to couple with a fluid path within the BFP 100 via a corresponding TC port 125a-125d (generally 125) on the BFP 100.
There are, in the most common implementation, four TCs 102 located on the BFP 100 in order to allow for temporarily attaching measuring equipment to measure the flow to ensure that the BFP 100 is functioning correctly.
Accordingly, a first TC 102-1 measures the pressure coming into the BFP 100; a second TC 102-2 measures the pressure just before a first check valve (not shown); a third TC 102-3 measures the pressure right after the first check valve; and a fourth TC 102-4 measures the pressure right after a second check valve (not shown).
Again, because of the public safety importance of the BFP, it is often a certified BFP Technician that conducts the testing to confirm that the BFP is in compliance with national standards bodies' requirements.
It is known to use an Electronic Pressure Sensor (EPS) to measure the fluid pressure at different points within the BFP. As such, a common approach to implementing an EPS redirects flow from a TC port 125-x to the EPS. This redirection, however, is implemented by coupling additional plumbing to the BFP 100 and oftentimes requires at least the following items: 1) an EPS; 2) one or more pipe fittings; 3) copper pipe (that will have to be cut to size); 4) one or more elbow fittings; 5) one or more ball valves; 6) installation equipment including, for example, a wrench, a soldering iron and associated solder and flux, etc.; and 7) labor costs for the installation as it needs to be performed by a certified professional.
Accordingly, what is needed is a better system for monitoring the status of a BFP.
In one aspect of the present disclosure there is a test cock for determining an operating condition of a backflow prevention system comprising: a body portion having a distal end and a proximal end; a space defined within the body portion; a distal opening provided on the body portion at the distal end; a proximal opening provided on the body portion at the proximal end, wherein the proximal opening is in fluid connection with body portion space; a body portion fitting disposed in the body portion, the body portion fitting providing a fluid connection with the body portion space; and a fluid sensor, coupled to the body portion fitting, in fluid connection with the body portion space.
The fluid sensor comprises at least one of: a pressure sensor; a temperature sensor; a pH sensor; a salinity sensor; and a wet/dry sensor.
The test cock can further comprise a ball valve disposed in the body portion in fluid connection with the distal opening and the body portion space. A spring clip can be provided that couples the fluid sensor to the body portion fitting.
The test cock can further comprise a system fitting, having a first end and a second end, the second end provided in the body portion proximal opening. A spring clip can couple the system fitting to the body portion proximal end. The body portion proximal end can be configured to rotate within the system fitting.
Another aspect of the present disclosure is a backflow prevention system comprising a backflow preventer; a system fitting, having a first end and a second end, provided on the backflow preventer; and the test cock referenced above.
Various aspects of the disclosure are discussed herein with reference to the accompanying Figures. It will be appreciated that for simplicity and clarity of illustration, elements shown in the drawings have not necessarily been drawn accurately or to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity or several physical components may be included in one functional block or element. Further, where considered appropriate, reference numerals may be repeated among the drawings to indicate corresponding or analogous elements. For purposes of clarity, however, not every component may be labeled in every drawing. The Figures are provided for the purposes of illustration and explanation and are not intended as a definition of the limits of the disclosure. In the Figures:
This application claims priority from U.S. Provisional Patent Application Ser. No. 62/844,912 entitled “Backflow Prevention System Test Cock With A Fluid Sensor,” filed May 8, 2019, and from U.S. Provisional Patent Application Ser. No. 62/869,195 entitled “Wireless Communication System Within A Mechanical Room,” filed Jul. 1, 2019, the entire contents of each of which is incorporated by reference in its entirety for all purposes.
The subject technology overcomes many of the known problems associated with backflow prevention assemblies. The advantages, and other features of the technology disclosed herein, will become more readily apparent to those having ordinary skill in the art from the following detailed description of certain exemplary embodiments taken in combination with the drawings and wherein like reference numerals identify similar structural elements. It should be noted that directional indications such as vertical, horizontal, upward, downward, right, left and the like, are used with respect to the figures and not meant in a limiting manner.
A test cock (TC) 200, in accordance with one aspect of the present disclosure, as shown in
Referring now to
In one approach, in accordance with an aspect of the present disclosure, a BFP fitting 312, i.e., a system fitting, is used to secure the TC 200 to the body of a BFP 100. The BFP fitting 312 includes a threaded end 315 to attach to the BFP body and a non-threaded end 320 to be received in the proximal opening 320 of the TC 200. The non-threaded end 320 allows the TC 200 to rotate, i.e., there is no constraining orientation. Another flexible fastening clip 325 is provided to couple the BFP fitting 310 to the TC 200 with a fluid-tight seal. The fastening clip 325 can be an e-clip or a c-clip or the like. Alternatively, the fitting 225 can be implemented as a key- or snap-fitting.
The EFS device 300 can be powered by a long life battery that could be replaced at one of the code-required annual tests or when indicated. Alternatively, the EFS device 300 can be hardwired to a continuous power source, such as an in-wall power line, and/or provided with a battery backup feature in the event of a power outage. Still further, the EFS device 300 can be connected to a control/monitoring system in a number of ways including, but not limited to, Ethernet, RF or other wireless transmission mechanism, etc., where a low-power status could be reported and addressed.
A BFP system 400 is shown in
Referring now to
A catch portion 525 of the body portion 505 has a larger outer diameter than the proximal end 515. A circumferential catch groove 530 is provided about the body 505 on the distal side of the catch portion 525 where the catch groove 530 has a smaller diameter than the diameter of the catch portion 525.
Referring now to
The TC port 605 may be screwed into the body of the BFP 600, as per known approaches. As shown in
Alternatively, the TC port 605 may initially not have the clip 715 in place. Once the snap-in TC 500 is in position with the catch groove 530 aligned with the openings 710, the clip 715 can be inserted to couple the snap-in TC 500 to the TC port 605.
Advantageously, the snap-in TC 500 is then able to be rotated 360° as presented in
In another aspect of the present disclosure, the proximal end 215 of the TC 200 can be configured as per the proximal end 515 of the snap-in TC 500. More specifically, instead of coupling to the BFP fitting 312, the proximal end 215 would include a catch portion and a circumferential catch groove as described above. Such a TC would then be inserted in a TC port 605 per the teachings set forth above.
The foregoing subject technology has a number of benefits over the known approaches, including, but not limited to: eliminating unnecessary valves, fittings and elbows as there is no need to redirect flow to a non-local EFS device; providing a TC assembly that can rotate 360° and, therefore, additional clearance is provided with a greater degree of freedom; permitting sensor installation in areas even if a full rotation is not possible, e.g., in areas where installing the sensor package with a conventional threaded connection would not be possible due to physical interference(s); and with an EFS device in each TC at multiple points on a BFP, the BFP can be continuously monitored in real-time to identify potential problems earlier without having to rely on finding an issue at the annual checkup.
Another aspect of the present disclosure presents technology that overcomes many of the known problems associated with wireless communication in mechanical rooms where BFPs are commonly located. Specifically, it is difficult to transmit and receive wireless signals from and to these mechanical rooms. Additionally, common modes of wireless communication, such as Wi-Fi and cellular data transmission, are power intensive modes that might require more power outlets than are commonly available is such rooms.
Referring now to
All devices 1002 are connected, via electrical lines 1006a-1006c, to their own in wall power source which powers the respective devices 1002, such as a main power supply for the building and/or the electrical grid. Notably, the devices 1002 within the mechanical room 1000 are exemplary only, and it should be understood that some or all devices 1002 may be omitted or replaced in different embodiments, or entirely different devices may be included, as could be found in typical mechanical rooms.
The valve 1005 can be part of a backflow preventer valve (BFP) system of the type discussed above and shown in
The sensor 1008 is in wireless communication with at least one of the devices 1002 within the mechanical room 1000 over a network. The network can be formed through direct wireless communication between the devices 1002 and the sensor 1008, or by communication of all the devices 1002 and the sensor 1008 through a common transceiver or the like (not distinctly show). The devices 1002 and sensor 1008 are configured to wirelessly communicate over the network using low power signal communication modes such as Bluetooth or RF. As such, it should be understood that all devices 1002 and the sensor 1008 can include the necessary components for wireless communication as are known in the art, such as receivers/transmitters, processors, and the like. In every case, the valve 1005 and/or sensor 1008 will include at least a transmitter for sending out data gathered by the sensor 1008 and at least one of the devices 1002 will include a receiver for receiving the data from the sensor 1008. In some cases, the valve 1005 contains a signal processor built into the sensor 1008 to analyze the data before transmitting a signal representative of that data.
Since the devices 1002 and sensor 1008 are all relatively local to each other within the mechanical room 1000, and transmission out of the mechanical room 1000 is not required for communication between the devices 1002 and sensor 1008, low power signal communication still allows for effective communication between the devices 1002 and sensor 1008 with lower bandwidth usage and power consumption. Each sensor 1008 on the system can be powered by a standard, replaceable battery. Since power consumption is low, the batteries need to be replaced infrequently and no wires are required to be run from the sensor 1008 to other power sources.
Eventually, the data from the sensor 1008 reaches one of the devices 1002. Typically, transmission out of the mechanical room 1000 can be difficult, and often is not possible using low power communication techniques. In accordance with the subject technology, there are several ways to then communicate the data out of the mechanical room 1000, to an external location where it can be processed and/or otherwise used. One way to do so is by using known power-line communication (PLC) techniques over one or more of the electrical lines 1006. PLC techniques essentially allow a power line to function secondarily as an Ethernet cable, eliminating the need to run an additional wire since the device 1002, and by association the sensor 1008, can effectively transmit data out of the mechanical room 1000 using the existing power lines 1006. In some cases, the data can be communicated over the existing power lines 1006 to a central cloud 1004 where it is stored.
Referring now to
The device 1102 is also directly connected to a transceiver 1112. The transceiver 1112 can be a separate device connected to the device 1102 through a wired connection, or can be integrated as a part of the device 1102. The transceiver 1112 is generally configured to transmit data out the mechanical room using high power signal transmission (e.g. higher power than Bluetooth or the like) for receipt by an external receiver 1110. As such, the transceiver 1112 is configured to receive the signal from the sensor 1008 through the network using low power communication, amplify the signal to create a high power signal, and transmit the high power signal out of the mechanical room 1000 to the external receiver 1110. The transceiver 1112 can therefore include component parts configured to accomplish these tasks, including a receiver, an amplifier, a transmitter, and a processor and/or memory as needed.
Since the transceiver 1112 is directly connected to the device 1102 (i.e. locally and/or through a wired connection), the transceiver 1112 is also connected to the in wall power source via the electrical line 1106. Therefore the transceiver 1112 does not need to rely on a battery, and is able to transmit a high power signal indicative of data from the valve out of the mechanical room 1110 even though the electronics on the valve 1005 are only powered by a battery and transmitting a low powered signal. The transceiver 1112 can also be configured to receive signals from multiple different valves within the mechanical room 1000. To that end, many valves can be included in the mechanical room which provide data to the transceiver 1112 over a network using lower power signal transmission, and the transceiver 1112 can be tasked with transmitting all of this data out of the mechanical room 1000 via a high power signal. As such, the bulk of the power consumption needed to communicate data from the mechanical room 1000 is handled by the transceiver 1112 which is connected to a reliable and continuous in-wall power source.
In one aspect of the present disclosure there is a wireless communication system located within a mechanical room, the wireless communication system comprising: a valve including at least one sensor, wherein the at least the one sensor is configured to wirelessly communicate over a network using low power signal communication; and at least one device configured to connect to an in-wall power source, the device further configured to wirelessly communicate over the network using low power signal communication.
At least one device is configured to connect to a light fixture, the first device connected to the in-wall power source via the light fixture.
A first device of the at least one devices can be configured to connect to a wall outlet socket, the first device connected to the in-wall power source via the wall outlet socket.
A first device of the at least one devices can be configured to replace a first light switch controlling a light, the first device connected to the in-wall power source and including a second light switch to control the light.
It will be appreciated by those of ordinary skill in the pertinent art that the functions of several elements may, in alternative embodiments, be carried out by fewer elements, or by a single element. Similarly, in some other alternate embodiments, any functional element may perform fewer, or different, operations than those described with respect to the illustrated embodiment. Also, functional elements (e.g., check valves, shut-off valves, and the like) shown as distinct for purposes of illustration may be incorporated within other functional elements in a particular implementation.
While the subject technology has been described with respect to various embodiments, those skilled in the art will readily appreciate that various changes and/or modifications can be made to the subject technology without departing from the scope of the present disclosure.
This application claims priority from U.S. Provisional Patent Application Ser. No. 62/844,912 entitled “Backflow Prevention System Test Cock With A Fluid Sensor,” filed May 8, 2019, and from U.S. Provisional Patent Application Ser. No. 62/869,195 entitled “Wireless Communication System Within A Mechanical Room,” filed Jul. 1, 2019, the entire contents of each of which is incorporated by reference in its entirety for all purposes.
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