Abstract:
Landscape sprinkling systems that incorporate fire sensors, optional moisture sensors, and control electronics that continuously monitor the perimeter of a property for fire and/or smoke, and optionally low soil moisture conditions. When an alarm is detected, the systems automatically turn on selected sprinkler valves to water areas that would be most impacted by a fire or are in need of water. Wireless and wired system embodiments are disclosed.

Description:
BACKGROUND  
         [0001]    The present invention relates generally to landscape sprinkling systems, and more particularly, to landscape sprinkling systems that include remote fire and moisture sensing features.  
           [0002]    The present inventors live in a California community that is adjacent to a national forest, wildlife parks, and conservancy area. The community also has dedicated conservation areas throughout it that contain native vegetation that is not watered except by rain. Unfortunately, these areas are very prone to fires.  
           [0003]    A recent fire that affected this community burned very dry native vegetation that was located about fifty feet away from many dwellings. While no homes were lost, this was a terrifying experience for many, and revealed a real problem regarding planting that is in close proximity to dwellings that are in fire prone areas.  
           [0004]    There is a need for a landscape sprinkling system that would automatically turn on selected sprinkler valves to water specific areas to help minimize the impact of fires on a dwelling or other structure. Such a system would be particularly valuable in the event that occupants of the structure were not home, for example.  
           [0005]    Also, in the past, moisture sensors have been used that sense the amount of moisture in the ground and inhibit operation of the irrigation system in selected areas that are too wet and do not need additional water. However, such conventional moisture sensors are normally hard-wired in series with the sprinkler solenoid valve.  
           [0006]    It is therefore an objective of the present invention to provide for landscape sprinkling systems that have remote fire and moisture sensing features.  
         SUMMARY OF THE INVENTION  
         [0007]    To meet the above and other objectives, the present invention provides for landscape sprinkling systems that incorporate fire and/or smoke sensors and control electronics that continuously monitor the perimeter or other selected areas of a property for fire and/or smoke. Optional moisture sensors employed with the remote fire and/or smoke sensors implement integrated feedback-based systems.  
           [0008]    In the event that fire or smoke is detected, the systems automatically turn on selected sprinkler valves to water areas that would be most impacted by a fire. Remote areas of the property or areas adjacent to an affected property may therefore be watered before a fire reaches the property so as to minimize the impact of the fire on the property and structures thereon.  
           [0009]    Use of the optional moisture sensors allows for remote sensing of the moisture content of the ground. The optional moisture sensors output signals that allow specific low-moisture area of a landscape to be watered when needed.  
           [0010]    An exemplary system comprises one or more remote fire/smoke sensors (that may include an optional moisture sensor) that communicate with a master controller or fire controllers that are attached to sprinkler solenoid valves. The master controller controls the sprinkler solenoid valves in a conventional manner for normal irrigation purposes. In a first embodiment, the master controller controls the sprinkler solenoid valves in response to the detection of fire and/or smoke by the remote fire/smoke sensors in the event of a fire, or in response to signals output by the optional moisture sensors. In a second embodiment, the remote fire/smoke sensors communicate with the fire controllers to activate selected sprinkler solenoid valves in response to the detection of fire and/or smoke, or in response to signals output by the optional moisture sensors.  
           [0011]    The remote fire/smoke sensors may communicate with the master controller or fire controllers by way of radio frequency (RF) communication signals, or optionally by way of infrared communication signals if the sensors are located at relatively short distances from the master controller, and line-of-sight communication paths are present. The remote fire/smoke sensors are intended to be on at all times and each of them are separately identified and send a signal to the master controller at regular intervals indicating that they are operative. The remote fire/smoke sensors are preferably powered by a battery, but may be powered by a solar cell and battery combination. Alternatively, the remote fire/smoke sensors may be hard wired to the master controller, which has some desirable benefits, although this is may be a slightly more involved or costly implementation.  
           [0012]    In a first embodiment, the master controller includes a transmitter and one or more receivers that are used to poll the remote fire/smoke sensors (and optional moisture sensors). The master controller processes alarm signals transmitted by the remote fire/smoke sensors in the event that fire and/or smoke are detected by one or more of the remote fire/smoke sensors, or processes output signals from the optional moisture sensors indicating low moisture content. Once an alarm signal is received by the master controller, it is processed to turn on one or more solenoid valves that allow water to be sprinkled onto the affected area, or to hold off sprinkling in areas of excessive moisture.  
           [0013]    In a second embodiment, the remote fire/smoke sensors (and optional moisture sensors) communicate with fire controllers that are individually attached to respective sprinkler solenoid valves. In the event that fire and/or smoke are detected by a remote fire/smoke sensor, or low moisture is detected, signals are transmitted to one or more fire controllers responsible for the affected area to turn on the solenoid valves to sprinkle water onto the affected area.  
           [0014]    As was mentioned above, the present invention may incorporate moisture sensors along with the remote fire/smoke sensors. Remote fire/smoke sensors containing a moisture sensor have the ability to monitor the moisture content of the ground and output signals that are communicated to the master controller or fire controller to activate or inactivate sprinkler usage during normal irrigation operation. The output of the remote fire/smoke sensor would supercede the output of the moisture sensors in the case of a fire. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    The various features and advantages of the present invention may be more readily understood with reference to the following detailed description taken in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which:  
         [0016]    [0016]FIG. 1 is a block diagram that illustrates embodiments of exemplary landscape sprinkling systems implemented in accordance with the principles of the present invention;  
         [0017]    [0017]FIG. 2 is a block diagram that illustrates exemplary remote fire/smoke and moisture sensors that may be employed in the present invention;  
         [0018]    [0018]FIG. 3 is a block diagram that illustrates an exemplary fire controller that may be employed in the present invention;  
         [0019]    [0019]FIG. 4 is a block diagram that illustrates an exemplary master controller employed in the present invention; and  
         [0020]    [0020]FIG. 5 is a table that illustrates a typical serial communication protocol that may be used in the present systems  
     
    
     DETAILED DESCRIPTION  
       [0021]    Referring to the drawing figures, FIG. 1 is a block diagram that illustrates embodiments of exemplary landscape sprinkling systems  10  implemented in accordance with the principles of the present invention. The exemplary systems  10  comprise one or more remote fire/smoke sensors  11  that may each include an optional moisture sensor  11   a . The remote fire/smoke sensors  11  (and moisture sensors  11   a ) communicate with a master controller  12  or with fire controllers  15  that are attached to sprinkler solenoid valves  13 .  
         [0022]    The sprinkler solenoid valves  13  are coupled to a water supply  16  and to a plurality of sprinkler heads  14  that are part of separate irrigation areas or zones by way of pipes  17 , such as plastic (PVC) tubing  17 . The master controller  11  is electrically coupled to the sprinkler solenoid valves  13  using low voltage wiring  19  and controls them in a conventional manner during normal irrigation times, typically using 12 volt DC control signals.  
         [0023]    In a first embodiment of the system  10 , the master controller  11  controls the sprinkler solenoid valves  13  in response to the detection of fire and/or smoke by the remote fire/smoke sensors  11  in the event of a fire, or in response to signals output by the optional moisture sensors  11   a  indicating low moisture content of the soil.  
         [0024]    In a second embodiment of the system  10 , the remote fire/smoke sensors  11  communicate with the fire controllers  15  to activate selected sprinkler solenoid valves  13  in response to the detection of fire and/or smoke, or in response to signals output by the optional moisture sensors  11   a.    
         [0025]    The remote fire/smoke sensors  11  may communicate with the master controller  12  or fire controllers  15  preferably using radio frequency (RF) communication signals  18 , or may optionally use infrared communication signals  18 , for example. Infrared communication signals  18  may be used if the remote fire/smoke sensors  11  are located at relatively short distances from the master controller  12 , for example, and line-of-sight communication paths are present. The remote fire/smoke sensors  11  are operable at all times and each of them is separately identified and send a signal  18  to the master controller  12  when polled (generally at regular intervals) indicating that they are operative. This will be discussed in more detail below.  
         [0026]    [0026]FIG. 2 is a block diagram that illustrates an exemplary remote fire/smoke sensor  11  including the optional moisture sensor  11   a  that may be employed in the systems  10  shown in FIG. 1. The remote fire/smoke sensor  11  comprises a detector  23  that is coupled to the battery  21 . The detector  23  detects fire and/or smoke and outputs an alarm signal.  
         [0027]    The detector  23  is coupled to a microprocessor  24 , which is also coupled to the battery  21 . An optional moisture sensor  11   a  is also coupled to the microprocessor  24 . The moisture sensor  11   a  outputs a signal that is input to the microprocessor  24  when the moisture level of the soil in which it is placed falls below a set level or limit.  
         [0028]    The microprocessor  24  is coupled to a receiver  26  and to a transmitter  27 . The receiver  26  and transmitter  27  are coupled to the battery  21 . The receiver  26  and transmitter  27  are each coupled to an antenna.  
         [0029]    The exemplary remote fire/smoke sensor  11  is preferably powered by the battery  21 , but may be powered by a solar cell  22  and battery  21  combination. Alternatively, the remote fire/smoke sensor  11  may be hard wired to receive 12 volt DC power, such as from the master controller  11 . However, this is a bit more complicated, because it would also require the addition of a DC-DC converter  25  for converting a 12 volt DC input, output by the master controller  12 , for example, to a 5 volt DC output that powers the detector  23 , microprocessor  24 , receiver  26 , and transmitter  27 , and possibly the moisture sensor  11   a  if this is required.  
         [0030]    Nonetheless, it is relatively inexpensive to implement a hardwired solution at the sprinkler head  14  instead of paying for batteries  21  and solar cells  22 . This is because the DC-DC converter  25  is a three-terminal voltage regulator that costs on the order of $0.25. Furthermore, in the hard wired  10 , there is no requirement for solar or battery power at the sprinkler head  14  (except for power backup), there is a simple communication link and reliable channel. Burying wire during sprinkler system installation has minimal cost impact, and even in retrofit applications, it is very simple to lay wire with minimal intrusion.  
         [0031]    The transmitter  27  is used to transmit the alarm signal to the master controller  11  or fire controllers  15 , and to transmit signals indicating that it is operative. The receiver  26  is used to receive polling signals from the master controller  11  that cause the remote fire/smoke sensor  11  to transmit an output signal (data packet) indicating that it is operative. The “operative” output signal is transmitted to the master controller  11  when the remote fire/smoke sensor  11  is operative. The master controller  11  outputs a warning signal when the “operative” output signal is not received, thus indicating the presence an inoperative remote fire/smoke sensor  11 .  
         [0032]    Furthermore, the remote fire/smoke sensor  11  may be used to provide direct and autonomous control of a local solenoid valve  13 . This is achieved using a switch  28  that is coupled to the microprocessor  24  and wired to switch 12 volt DC power to the solenoid valve  13 . The microprocessor  24  outputs a trigger signal to the switch  28  in the event that an alarm signal or low water level signal occurs.  
         [0033]    Exemplary radio transmitters  27  and receivers  26  for use in the system  10  are available from Micrel Semiconductor, for example. The Micrel devices are known as QuikRadio™ transmitters and receivers and are single-chip RF integrated circuits that employ amplitude-shift-keyed/on-off keyed (ASK/OOK) modulation. These circuits are relatively low in cost and are easily integrated into the system  10 .  
         [0034]    Other RF transmitters  27  and receivers  26  are available from Ericsson and National Semiconductor which conform to the Bluetooth™ specification. The Bluetooth transmitters and receivers provide point-to-point and point-to-multipoint wireless RF connectivity between the transmitters and receivers.  
         [0035]    Exemplary moisture sensors  11   a  that may be adapted for use in the systems  10  are available from Global Water Instrumentation, Inc., Gold River, Calif., Davis Instruments Corp., Hayward, Calif., and Environmental Sensors Inc., Victoria, British Columbia, for example.  
         [0036]    [0036]FIG. 3 is a block diagram that illustrates an exemplary fire controller  15  that may be employed in the systems  10  shown in FIG. 1. The exemplary fire controller  15  may be powered by a battery  31 , but may be powered by a solar cell  32  and battery  31  combination. The fire controller  15  may also be powered using 12 volt DC power. The use of the battery  31  provides added protection in the event that utility power is lost due to a major fire.  
         [0037]    The fire controller  15  comprises a microprocessor  33  that is coupled to a receiver  35  and a transmitter  36 . The microprocessor  33  is also coupled to a switch  37 . The switch  37  is coupled to receive 12 volt DC power that is ultimately switched to the solenoid valve  13  coupled thereto. The battery is coupled to the microprocessor  33 , the receiver  35 , and the transmitter  36 . The microprocessor  33  outputs a trigger signal to the switch  37  in the event that an alarm signal (or low water level signal) is received.  
         [0038]    In the case where the fire controller  15  is powered using 12 volt DC power, the fire controller  15  comprises a DC-DC converter  34  (or voltage regulator  34 ) that is coupled to a 12 volt DC input derived from the master controller  12 , for example. The DC-DC converter  34  converts the 12 volt DC input to a 5 volt DC output that powers the receiver  35  and transmitter  36  (such as a Micrel receiver and transmitter, for example). The receiver  33  outputs a trigger signal that is applied to a switch  34  that switches the 12 volt DC input to the solenoid valve  13  when a signal is received from the remote fire/smoke sensor  11  or moisture sensor  11   a.    
         [0039]    [0039]FIG. 4 is a block diagram that illustrates an exemplary master controller  12  employed in the systems  10  shown in FIG. 1. The exemplary master controller  12  comprises a power supply  42  that is coupled to an AC voltage source. The power supply  42  is also coupled to a backup battery  41  and to a DC-DC converter  43 . The DC-DC converter  43  converts 12 volts DC into 5 volts DC, for example. The DC-DC converter  43  is coupled to a transmitter  47  and to one or more receivers  48 . The one or more receivers  48  are coupled to a master fire controller  44 .  
         [0040]    The power supply  42  is coupled to the master fire controller  44  and to a solenoid controller  45 . The power supply  42  is also coupled to a plurality of switches  46  and supplies 12 volts DC thereto. The master fire controller  44  and solenoid controller  45  are each respectively coupled to the plurality of switches  46  and are used to switch the 12 volt DC signal to solenoid valves  13  coupled thereto. The switches  46  are respectively coupled to individual solenoid valves  13 .  
         [0041]    The solenoid controller  45  is conventional and controls operation of the landscape sprinkling systems  10  during normal conditions. The master fire controller  44  controls operation of the solenoid valves  13  in the event of fire and optionally in the event of low moisture detected by the optional moisture sensor  11   a.    
         [0042]    The master fire controller  44  is contains substantially the same components that are employed in the fire controller  15 , except for the battery  31 , solar array  32  and DC-DC converter  34  shown and described with reference to FIG. 3. The master fire controller  44  also comprises a plurality of switches  37  corresponding to the number of solenoid valves  13  in the system  10  that are controlled thereby.  
         [0043]    The master controller  12  polls each of the remote fire/smoke sensors  11  on a regular basis to determine if they are operative. FIG. 5 is a table that illustrates an exemplary serial communication protocol that may be used in the present systems  10 .  
         [0044]    As is illustrated in FIG. 5, an exemplary data packet includes three (3) synchronization bytes, two (2) address bytes identifying a “To” address, two (2) address bytes identifying a “From” address, two (2) bytes indicating a data type, two (2) bytes indicating a data length, a plurality of data bytes, a verification checksum, and an end of message marker. By way of example, and as is shown in FIG. 5, an exemplary data packet may be as follows {@@@, A3, 01, 02, 06, A, 2, . . . , F, 3D, ###}. As for the data type, a “0” may be used to identify a “heartbeat”, i.e., that the sensor  11  is operational, a “1” may be used to identify a report request, a “2” may be used to identify a report response, and a “3” may be used to identify an unsolicited transmission, i.e., the alarm. It is to be understood that the number and use of the data identifiers may vary, and is at the discretion of the designer of the system  10 .  
         [0045]    The synchronization bytes are characters indicating the start of a packet. The “To” address comprises 16 bits and provides more than 65,000 remote device addresses. The “From” address comprises 16 bits and provides more than 65,000 remote device addresses. The data type comprises 16 bits and provides different definitions of the data that follows, including encryption, for example. The data length indicates how many bytes follow within the current packet. The data comprise individual bytes of data within the packet. The verification checksum comprises a number of bytes that indicates that the data packet arrived completely and correctly. The end of message marker comprises marker bytes that indicate the end of the current packet.  
         [0046]    Each remote fire/smoke sensor  11  has a unique identification (ID) number assigned to it, which is a predetermined number of bits of a data packet that is transmitted back to the master controller  12 . The data packet transmitted by the master controller  12  includes the identification (ID) number bits, one or more bits indicating that the sensor  11  is “operative”, and a checksum bit.  
         [0047]    During polling, the master controller  12  transmits a data packet containing the ID number of a selected remote fire/smoke sensor  11 . All remote fire/smoke sensors  11  receive and process the transmitted data packet. The processing of the data packet is performed in the microprocessor  24 . The selected remote fire/smoke sensor  11  having the ID number contained in the data packet responds to the received data packet by transmitting a data packet containing the “operative” output signal. The microprocessor  33  in the master controller  12  processes the received data packet containing the “operative” output signal to verify that the selected remote fire/smoke sensor  11  is operative.  
         [0048]    When an event occurs, such as detection of fire or smoke or a low moisture condition, the affected remote fire/smoke sensor  11  transmits a data packet to the master controller  12  that contains its identification (ID) number, a predetermined number of bits corresponding to an alarm output signal, and a checksum bit. The master controller  12  activates the appropriate solenoid valve  13  to sprinkle water onto the affected area of the landscape.  
         [0049]    Alternatively, the affected remote fire/smoke sensor  11  transmits the data packet to the corresponding fire controller  15  that controls the solenoid valve  13  for the affected area of the landscape. The fire controller  15  activates the associated solenoid valve  13  to sprinkle water onto the affected area of the landscape.  
         [0050]    Thus, remote sensing is provided by the remote fire/smoke sensors  11  (and remote moisture sensors  11   a ) and output signals from affected ones of the sensors  11 ,  11   a  are wirelessly communicated to the master controller  12  or fire controller  15  for processing and control of appropriate sprinkler heads  14  of affected irrigation areas or zones.  
         [0051]    In a wireless system embodiment, it is preferred that the remote fire/smoke sensors  11  are asleep most of the time, waking once per minute, for example, to test for smoke, heat or moisture. The remote fire/smoke sensors  11  would then autonomously transmit if an event has occurred, or if it is time for their regular heartbeat transmission. In general, one would not poll the remote devices since they are typically asleep. In a wired system embodiment, just the opposite is preferred, since unlimited power is available at the remote device. In this case, the communication wires would also carry the power, and polling is appropriate.  
         [0052]    Each of the remote fire/smoke sensors  11  are polled by the master fire controller  44 , generally at regular intervals. When polled, each of the remote fire/smoke sensors  11  respectively output a data packet indicative that it is operational. The data packet is transmitted to the master fire controller  44  by way of its one of more receivers  48 , or to the fire controllers  15  by way of their receiver  35 . An alarm signal is output by he master fire controller  44  in the event that one of the remote fire/smoke sensors  11  is not operational.  
         [0053]    Thus, the master controller  12  or fire controllers  15  thus process alarm signals transmitted by the remote fire/smoke sensors  11  in the event that fire and/or smoke is detected, or process output signals from the optional moisture sensors indicating low moisture content. Once an alarm signal is received by the master controller  12  or fire controllers  15 , it is processed to turn on one or more solenoid valves  13  that allow water to be sprinkled onto the affected area.  
         [0054]    Thus, landscape sprinkling systems that include remote fire and moisture sensing features have been disclosed. It is to be understood that the described embodiments are merely illustrative of some of the many specific embodiments which represent applications of the principles of the present invention. Clearly, numerous and other arrangements can be readily devised by those skilled in the art without departing from the scope of the invention.