Abstract:
A fire hydrant water leak and theft detection system is connected to a dry barrel fire hydrant. The detector is connected to the upper barrel portion of the fire hydrant below the nozzle assembly and includes a pair of electrodes. A signal is generated when water in the upper barrel portion closes an electrical circuit between the two electrodes due to the conductivity of the water between the electrodes. The detection system sends a signal to a network system upon detection of water in the barrel portion and relays to remote monitoring locations.

Description:
BACKGROUND 
     The present disclosure generally relates to a device and method for monitoring the water level in a fire hydrant. More specifically, the present disclosure relates to a detector connected to a fire hydrant that communicates signals indicative of water present in the fire hydrant, as well as the status of the detector, to a central computing/network system. 
     Presently, several devices are available in the commercial marketplace for determining whether or not water is being discharged from the hydrant due to theft, leaks, and/or removal of the hydrant itself. Present detectors sense the presence of water by detecting flow across sensors, voltage drop across sensors, and the like. Additionally, present detectors are not remotely monitored. 
     SUMMARY 
     The present disclosure relates to a detector that senses the presence of water in a fire hydrant barrel. The detector includes a communication device to send a radio, cellular or other wireless signal to a central computing/network system or signal collection station. 
     The detector includes a pair of electrodes that form a portion of an open electrical circuit. During a low water level event, the electrical circuit remains open and no signal is produced by the detector. In contrast, at a high water mark, water closes the electrical circuit and allows electrical current to flow from one electrode to another causing a controller to produce a signal. 
     The conductivity of the water is linked to the total dissolved solids in the water. The water in a fire hydrant barrel contains a percentage of total dissolved solids that allows the current to flow through the water. The inventors of the present invention has recognized that using these inherent conductive properties of the water flowing through the barrel is a reliable and inexpensive way to determine if water is present at the location when the detector is installed on the barrel. 
     In some examples, a fire hydrant monitoring system for a fire hydrant includes a housing and an inlet. The housing is connected to the exterior surface of the barrel. The system also includes a controller and a pair of electrodes. The controller is located in the housing and the pair of electrodes are connected to the controller. The controller and the electrodes form an open circuit. When water enters the housing and flows between the electrodes, the open circuit is closed and the controller processes a signal. 
     In other examples, a detector for monitoring the presence of water in a fire hydrant includes a housing, an inlet, and a sensing chamber. The housing is connected to the fire hydrant, and the inlet is connected to the sensing chamber. The detector also includes a pair of electrodes, a sensor interface, a processing device, a communication device, an antenna controller, and an antenna. Each electrode includes a first end and second end. The first ends positioned in the sensing chamber and the second ends connected to the sensor interface. The sensor interface and electrodes form an open circuit. The sensor interface is connected to the processing device. When water is located between the two electrodes the open circuit is closed and the processing device processes a signal. The processing device is connected to the communication device, the antenna controller, and antenna which transmits the signal. 
     Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings illustrate the best mode presently contemplated of carrying out the disclosure. In the drawings: 
         FIG. 1  is a side view a fire hydrant above grade including the water detector device of the present disclosure. 
         FIG. 2  is a cross sectional view of the fire hydrant of  FIG. 1  and includes portions of the fire hydrant that are below grade. 
         FIGS. 3A-3D  are enlarged section views of the valve assembly of the fire hydrant in the present disclosure. 
         FIG. 4  is an enlarged section view of the device of the present disclosure. 
         FIG. 5  is a block diagram illustrating the device circuitry. 
         FIG. 6  is a block diagram illustrating the processing device shown in  FIG. 6  of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1-2  illustrate a fire hydrant water detector  50  in accordance with the present disclosure. The detector  50  is shown connected to a fire hydrant  4 . In one example, the detector  50  is connected to a conventional dry barrel fire hydrant  4  which includes a barrel  18  connected to the water main  14  by a pipe fitting  12 , such as a tee or elbow. In most applications, the water main  14  is buried below grade  10 . The barrel  18  is substantially perpendicular to the water main  14  and rises upwardly from the pipe fitting  12 . 
     Referring to  FIG. 2 , the fire hydrant  4  includes a valve assembly  35 , an operating mechanism  30 , and a nozzle assembly  23 . 
     The barrel  18  includes an upper barrel  19  and a lower barrel  20 . The lower barrel  20  is connected to the upper barrel  19 , and the upper barrel  19  extends above grade  10  such that a portion of the fire hydrant  4  is accessible to fire departments and/or utilities. The operating mechanism  30  and a nozzle assembly  23  are connected to the upper barrel  19 . 
     The nozzle assembly  23  includes at least one nozzle outlet  24 , which extends substantially lateral from the upper barrel  19 . A nozzle cap  25  is removably connected to the nozzle outlet  24  and prevents water from flowing out of the fire hydrant  4  and/or prevents contaminates from entering the upper barrel  19 . The nozzle outlet  24  includes threads that allow fire fighting hoses or other apparatus to be removably connected to the nozzle outlet  24 . 
     The operating mechanism  30  is connected to the valve assembly  35  by an operating rod  31 . The operating rod  31  is an elongated shaft (one or two piece) extending through the lower barrel  20  and upper barrel  19 . In one example, the operating mechanism  30  includes an operating nut  32  that is accessible from the top of the upper barrel  19 . The size and shape of the operating nut  32  is the same as the nozzle nut  26  on the nozzle cap  25 . In operation, the operating nut  32  is rotated counterclockwise by an operator causing the operating rod  31  to also rotate in a counterclockwise direction. Under the rotation, the valve assembly  35  moves between a closed position ( FIG. 3A ) to a partially open position ( FIG. 3B ) and further to a fully open position ( FIG. 3C ). Alternatively, if the operating nut  32  is rotated in a clockwise direction, the valve assembly  35  moves in the opposite direction from the fully open position ( FIG. 3C ) to a closing position ( FIG. 3D ) and further to a closed position ( FIG. 3A ). 
     Referring to  FIG. 3A-3D , the valve assembly  35  controls the flow of water moving into the barrel  18 . The valve assembly  35  includes a series of plates, seats, flanges, gaskets, and other elements. As depicted in  FIG. 3A , the valve assembly  35  is in a fully closed position. In this closed position, pressurized water from the water main  14  does not enter the barrel  18 . Turning to  FIG. 3B , as the operating rod  31  rotates counterclockwise, the valve assembly  35  is depicted in a partially open position. In the partially open position, a space between the valve assembly  35  and the pipe fitting  12  allows water to enter the barrel  18 . As water continues to enter the barrel  18 , the water level in the barrel moves upward through the lower barrel  20  and into the upper barrel  19 . With further rotation of the operating rod  31 , the valve assembly  35  moves to the fully open position, as depicted in  FIG. 3C . Once the water level reaches an open nozzle outlet  24 , the water may exit the barrel  18 . 
     To close the valve assembly  35  and prevent water from flowing out of the nozzle outlet  24 , the operator applies a clockwise rotation to the operating nut  22 . Under this rotation, the valve assembly  35  moves to the closing position, as depicted  FIG. 3D . Further clockwise rotation moves the valve assembly  35  back to a fully closed position, as depicted in  FIG. 3A . Once closed, any water remaining in the barrel  18  below the level of the open nozzle outlet drains from the barrel  18  through weep holes or drain valves  16  located at the bottom of lower barrel  20 , as shown by arrow  36  in  FIGS. 3B and 3D . In some examples, the drain valves  16  may be connected to the pipe fitting  12 . 
     If the weep holes or drain valves  16  become clogged with debris or any other foreign matter, the water in the barrel  18  will not properly drain. In climates where the temperature drops below freezing, if the water does not properly drain and freezes, the expansion of the frozen water can create problems and damage the operating components of the fire hydrant. 
     Now referring to  FIG. 4 , an enlarged view of the detector  50  is depicted. The detector  50  is connected to the upper barrel  19 . In one example, the detector  50  is connected to the upper barrel  19  below the nozzle assembly  23 , as shown in  FIG. 1 . The detector  50  includes a housing  52  and an inlet fitting  53 . In one example, the inlet fitting  53  is generally cylindrical and includes screw threads  54  on an attachment portion  55  and drain surfaces (not shown). In operation, the inlet fitting  53  is connected to the upper barrel  19  at a threaded receiver hole  58  in the upper barrel  19 . However, one of ordinary skill in the art will recognize that the inlet fitting  53  may be connected to the upper barrel  19  in any suitable way including screw threads, adhesives, snap fittings, and the like. In other examples the detector  50  may be connected to the nozzle outlet  24 . It will also be recognized that additional components, such as gaskets, fittings, and the like, may be used to connect the detector  50  to the barrel  18 . When connected to the upper barrel  19 , the housing  52  is adjacent to or in contact with the outer surface of the upper barrel  19 . Gaskets and/or O-rings may be included between the inlet fitting  53  and the upper barrel  19  to create a fluid tight seal. 
     The drain surfaces of the inlet fitting  53  may be connected to the inlet fitting  53  and/or the housing  52 . In some examples, the drain surfaces are integral with the housing  52 . The inlet fitting  53  includes an open sensing chamber  56 . The sensing chamber  56  is an open space defined by the outer wall of the inlet fitting  53  and is open to the open interior  65  of the upper barrel  19 . The sensing chamber  56  is independent and sealed from the other portions of the detector  50  to prevent water damage to other components. 
     When the detector  50  is in operation and connected to the barrel  18 , as described above, the detector  50  determines whether or not water is present in the barrel  18  at the elevation where the detector  50  is installed. Water may sensed by the detector  50  when the hydrant  4  is being operated by an authorized or unauthorized user, when water is being stolen from the hydrant  4 , when there is a leak in the valve assembly  35  that causes water to continuously fill the barrel  18 , and/or when the drain valves  16  are blocked. 
     Water in the barrel  18  flows into the sensing chamber  56  of the inlet fitting  53  of the detector  50 . The inlet fitting  53  includes a cap  66  that includes at least one sensing hole  57  to provide access to the sensing chamber  56 . The sensing holes  57  may be sealed with a gasket, glue, caulk, O-rings, and the like to prevent water from moving into other portions of the housing  52 . The sensing holes  57  allow at least one electrode  59 ,  62  to extend into the sensing chamber  56 , and each electrode  59 ,  62  includes a first end  60 ,  63  and a second end  61 ,  64 . The first ends  60 ,  63  of the electrodes  59 ,  62  protrude through the sensing holes  57  and are positioned in the sensing chamber  56 . The second ends  61 ,  64  of the electrodes  59 ,  62  are connected to a controller  70 , to be discussed further herein. The first ends  60 ,  63  of the electrodes  59 ,  62  are separated by a distance D such that the controller  70  and electrodes  59 ,  62  form an open electrical circuit. 
     As mentioned above, the electrodes  59 ,  62  are positioned in the sensing chamber  56  such that they from an open electrical circuit with the controller  70 . However, when water is present between the electrodes  59 ,  62 , such as when the water level reaches a high water mark  6 , the electrical circuit is closed and an electrical current can flow through the water due to the electrical conductivity of the water. When the circuit is closed, the controller  70  is placed into an alert mode and is capable of producing a water-present signal. When the circuit is open, the controller  70  may remain in a sleep mode and produces a no-water-present signal or no signal at all. It will be recognized that the high water mark  6  may be any water level that allows water to flow between the two electrodes  59 ,  62 . 
     Now referring to  FIG. 5 , the controller portion of the detector is depicted in greater detail. As mentioned above, the second ends  61 ,  64  of the electrodes  59 ,  62  are connected to a controller  70  located inside the housing  52 . The controller  70  includes a sensor interface  71 , a processing device  72 , power supply  73 , and a communication device  74 . In some examples the controller  70  may also include an antenna connector  75  and an antenna  76 . The processing device  72  controls the sensor interface  71  and the communication device  74 . The processing device  72  may continually or periodically monitor the status of the sensor interface  71 . 
     In some examples, the second ends  61 ,  64  of the electrodes  59 ,  62  are connected to the sensor interface  71 . When water between the electrodes  59 ,  62  forms a closed circuit, the processing device  72  will generate an alarm or warning signal to the communication device  74 , to be described further herein. The processing device  72  may also aggregate and store multiple alarm or warning signals from the sensor interface  71  on a memory (not shown). For instance, the processing device  72  may monitor the status of the sensor interface  71  for several hours before relaying signal data to the communication device  74 . In this example, each water-present signal or no-water-present signal is held in the memory with an appropriate time stamp until the processing device  72  is scheduled to relay the signal data to the communication device  74 . The aggregation of data and sending periodic signal data helps to minimize power consumption. It is also contemplated that the processing device  72  may encrypt and/or transform signal data from the sensor interface and/or data from the communication device  74  into different data formats. 
     Since the processing device  72  will generate an alarm or warning signal every time water is present between the pair of electrodes  59 ,  62 , such signal will also be generated during authorized testing of the fire hydrant. In order to prevent alarm signals from being generated during authorized testing, the detector  50  can be configured to include some type of override device. Such an override device may include a unique password or code that is entered into the controller  70  using a user interface (not shown) on the housing  52  or some type of wireless communication. When authorized personnel, such as a fire department or utility, wishes to test the hydrant, the authorized personnel can enter the unique code or override signal to temporarily suspend generation of the alarm or warning signal from the controller  70 . During the authorized testing, water present between the pair of electrodes  59 ,  62  would not generate an alert or alarm condition, which would avoid nuisance alarms being received at the utility. Once the authorized testing is complete, the override would be disabled and the detector  50  would continue operating in a normal manner. 
     The communication device  74  is connected to an antenna connector  75  and an antenna  76 . The communication device  74  processes the data from the processing device  72  and transmits the data via the antenna connector  75  and the antenna  76 . The communication device  74  may use various types of communication networks and protocols, such as FlexNet®, Wi-Fi, low-energy Bluetooth®, and the like. The communication device  74  may communicate with a router, a modem, handheld remote receiver unit, and/or cloud services for retrieval and analysis including internet accessibility. One of ordinary skill in the art may also recognize that the communication device  74  may be a wired connection. The communication device  74  may also act as a transceiver, and thus receive data from external sources. The antenna  76  is connected to the antenna connector  75 , and the antenna  76  may be positioned inside the housing  52 , attached to the outside the housing  52 , or partially inside the housing  52 . It is also contemplated that an intermediate base station may be provided between the detector  50  and the utility. The base station may collect signals from multiple detectors  50  before communicating the signals to the utility via the internet. 
     The power supply  73  is connected to the processing device  72  and the communication device  74 . It should also be known to those having ordinary skill in the art that the power supply  73  may provide power to other components of the detector  50 . It is also contemplated that the power supply  73  may be any type of power component such as a battery, rechargeable battery, and the like. It is further contemplated that the power supply  73  may include thermal couples, photovoltaic cells, vibration kinetic motion converters, and the like. The power supply  73  may also be a wired connection via AC source, DC source, Ethernet connection, and the like. In one example, the power supply  73  in a battery that contains enough electrical power to power the detector  50  for at least ten years under normal operation. 
     Turning now to  FIG. 6 , a block diagram showing an example of the processing device  72  is shown. The processing device  72  depicted in  FIG. 6  may include the devices and interfaces discussed above as well as a power assembly  82 , a communication module  83 , a water detection module  84 , a heartbeat module  85 , and a timer/sleep module  86 . 
     The power assembly  82  may be connected to the power supply  73 , and the power assembly  82  may control the voltage and current levels provided to the processing device  72  and/or the communication device  74 . The communication module  83  connects to the communication device  74  and receives and/or sends signals for communication through the communication device  74 . The water detection module  84  may be configured to analyze the status of the circuit formed by electrodes  59 ,  62  and the sensor interface  71 , as described above. Besides the presence of water between the electrodes  59 ,  62  to complete the circuit and detect the presence of water, the water detection module  84  may determine the probability and/or likelihood that signals are indicative of a water-present situation or some other situation, such as damaged electrodes  59 ,  62  and a blocked inlet  53 . The water detection module  84  may create alarm signals when the detector  50  is tampered with, broken, or moved to a non-standard orientation. 
     The heartbeat module  85  is connected to the processing device  72  and communicates the status of the detector  50  to the utility through the communication device  74 . In one example, the heartbeat module  85  processes a heartbeat signal every two to eight hours essentially broadcasting that the detector  50  is operational and operating normally. 
     The timer/sleep module  86  controls the sleep modes in order to minimize power supply  73  usage when the detector  50  is not in use. The timer/sleep module  86  is configured to wake different components discussed herein at set pre-programmed times. The timer/sleep module  86  may also be configured to wake up different components when specific circumstances are sensed by the detector  50  such as a large flow of water or damage to the detector  50 . 
     It is also contemplated that the detector  50  may include other sensors such as pressure sensors, tilt sensors, and the like. One of ordinary skill in the art will recognize that additional sensors added to the detector will include corresponding circuitry similar to those components and/or modules described above and tailored to the additional sensors. 
     This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.