Abstract:
An automatic mist-sprayer system comprising a control unit having electronic circuitry adapted to activate the sprayer for a predetermined interval in response to a sensed ambient light condition of desired intensity and duration. The system desirably further includes an electrical power supply and a plurality of spaced-apart sprayer heads. A preferred utility for the system of the invention is spraying dilute solutions of insecticide or insect repellent during the periods of significant insect activity that typically occur around dusk and dawn. Manual overrides and a remote receiving unit are also disclosed for use of the system at times other than dusk and dawn.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     This invention relates to a system useful for spraying a fluid mist through an array of sprayer heads to treat the atmosphere in a location that is generally defined by the array, and more particularly, to a light-activated mist sprayer system that initiates a flow of treating fluid in response to a sensed ambient light condition of desired intensity and duration. Once initiated, the fluid mist spray desirably continues for a predetermined interval. A preferred application for the system is for eradicating or repelling flying or crawling insects during the periods of significant insect activity that typically occur around dusk and dawn.  
         [0003]     2. Description of Related Art  
         [0004]     Problems associated with the presence of mosquitoes and other flying insects are well known, particularly during summer months when people typically engage in many outdoor activities. People have long appreciated the dangers associated with mosquito-borne diseases such as malaria and equine encephalitis. More recently, publicity associated with the West Nile virus in has heightened public awareness of dangers that can be associated with mosquito bites. Additionally, people are generally aware of the pain, discomfort and potentially dangerous allergic reactions that can accompany the bites of various flying and crawling insects encountered outdoors in either urban or rural areas.  
         [0005]     Various chemical sprays and devices have previously been used to control flying and crawling insects, spiders, and other such pests. Chemical sprays containing environmentally acceptable concentrations of insecticides or pesticides have historically been applied using hand-held sprayers, fogging machines, and the like. Such sprays are sometimes applied by governmental agencies in parks, residential neighborhoods and other high-risk urban areas, but are most often applied by individuals using hand-held sprayers in and around their own homes and yards. In more rural settings, sprayer systems have previously been used to spray insecticides or pesticides in and around barns, livestock holding areas, and the like. Other devices that have previously been used to control insects and other pests have incorporated a lure or an attractant, such as food baits, light, pheromones, or carbon dioxide, to draw the insects or pests to a trap, electrically energized grid, or poison.  
         [0006]     Many of the prior art systems and devices for controlling insects and pests are operated directly by the user. Others are controlled by timers that are preset to initiate their function at a particular time and for a particular interval. In some cases, the electrical energy required to operate the devices, particularly those disposed in remote or rural areas where electricity is not readily available, is obtained from batteries or solar cells. U.S. Pat. No. 6,192,621, for example, discloses a pest control device for outdoor use comprising a solar-powered fan that enhances the circulation of odorous repellent to the external ambient environment. U.S. Pat. No. 5,763,873 discloses an agricultural implement for spraying herbicides on weeds that utilizes a photo-detector circuit to avoid spraying the herbicide on bare soil. The photo-detector circuit is not affected by changes in ambient lighting conditions.  
         [0007]     Various solar-powered devices have previously been disclosed that utilize solar-powered batteries to store electrical energy during daylight hours for use in operating electric timers capable of turning one or more outdoor lights on and off daily and, in some cases, for powering those lights. The use of photocells for activating or deactivating a mechanical device upon receipt of light is also well known. Photocells are most often triggered by the impingement or interruption of a directed light beam and not by ambient light. U.S. Pat. No. 6,756,758 discloses receiver circuits for detecting a target light source that effectively remove “noise,” including ambient daylight, during the operation of such devices. Other devices have been disclosed that turn one or more lights on or off in response to predetermined levels of ambient light.  
         [0008]     U.S. Pat. No. 4,015,366 discloses a highly automated agricultural production system comprising a weather sensor package used to measure weather conditions, including the sunlight energy spectrum, the intensity of which is measured using a plant growth photometer said to be available from International Light, Inc. The system is said to optionally include a fluid delivery system useful in controlling insects and diseases, but is complex and not desirable for home use.  
         [0009]     Mosquitoes, flies and other insects are most easily controlled when they are most active, often during the time around sunrise and sunset. The use of timers alone to activate spraying or misting systems is often inadequate for initiating spraying at the onset of the relatively short periods when such pests are most active. Timers alone are not responsive to variations in daylight hours, weather conditions and topography that can all affect ambient light levels and insect activity at a particular time of day in a particular location.  
         [0010]     A mist sprayer system is therefore needed that will activate automatically at dusk or dawn and spray for a preset interval, that can optionally be activated manually or by using a remote transmitter, and that will be effective for eradicating or repelling flying and crawling insects, spiders and the like from outdoor areas in which the system is deployed.  
       SUMMARY OF THE INVENTION  
       [0011]     The present invention is a mist sprayer system that preferably comprises an ambient light sensor, electronic circuitry that evaluates an electrical signal received from the light sensor to determine whether a “dusk” or “dawn” light condition exists; a container, reservoir or other source of treating fluid at a desired concentration; a pump that is activated at the appropriate time as determined by the sensed light condition; at least one sprayer head, and preferably an array of spaced-apart sprayer heads, each having a nozzle that will dispense a mist containing the treating fluid whenever the pump is operating; flexible tubing or other conduits providing fluid communication between the fluid source and the sprayer heads; and a timer that turns off the pump after a preset interval to terminate the spraying cycle. According to a preferred embodiment of the invention, the electronic control unit comprises a light level discrimination module, a pump control module, a power supply module, a remote receiver module, and optionally, a remote transmitter for activating the pump control module.  
         [0012]     One preferred application for the system is for spraying a mist comprising a treating fluid useful for eradicating or repelling flying or crawling insects such as mosquitoes, wasps, bees, spiders, and the like, that may be injurious to humans or livestock. Examples of outdoor areas that can be serviced by the systems of the invention include, for example, residential or commercial yard and patio areas, swimming pools, outdoor restaurants, horse and livestock barns, garbage dumpsters and compactors, food processing plants, parks and picnic areas, boat houses, dog kennels, zoos, amusement parks, industrial sites, and the like. Systems of the invention can similarly be used for controlling insects and the diseases they carry in vineyards, vegetable fields, orchards, greenhouses, nurseries and such, or for repelling dogs and wild animals such as foxes, squirrels, rabbits, and the like, that can become pests in gardens or other restricted areas. With an appropriate treating fluid, for example, the system of the invention can possibly be used to repel rabbits or birds from aircraft taxi and runway areas on airport properties.  
         [0013]     The system of the invention can be easily, effectively and reliably used to dispense a variety of treating fluids, most preferably liquids, but optionally, gases or liquids containing dissolved, entrained or suspended gaseous or powdered solid components. The treating fluids are preferably dispensed as a mist, and are preferably selected from known, commercially available insecticides, pesticides, insect or pest repellents, fungicides, biocides, and the like, and can optionally include an attractant component as a lure. It will also be appreciated upon reading the disclosure that the subject system can likewise be used for dispensing other treating fluids “on demand” including, for example, liquid fertilizers, air fresheners, cooling water, and the like, and at times other than dusk and dawn.  
         [0014]     The system of the invention replaces standard timers or programmed controllers previously used in automated dispensing systems, and, because the dispensing cycles are triggered by prevailing ambient light levels, will typically operate only during the times when flying and crawling insects and pests are most active. By automatically initiating chemical treating for defined intervals during the periods of greatest insect activity, the user is able to reduce the amount of treating fluid required, and to thereby achieve better results at lower cost. The system is automatically responsive to use in various time zones and topographies, and will automatically adapt to the lengthening and shortening daylight hours that are normally associated with seasonal changes. In addition to having an automatic light-activated capability unlike that of other known systems and devices, the mist sprayer system of the invention can also be activated manually or by using a wireless remote transmitter if desired.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]     The apparatus of the invention is further described and explained in relation to the following drawings wherein:  
         [0016]      FIG. 1  is a simplified diagrammatic view of a preferred embodiment of the light-activated mist sprayer system of the invention as installed;  
         [0017]      FIG. 2  is a front elevation view of a preferred electronic control unit for use with the light-activated mist sprayer system of the invention;  
         [0018]      FIG. 3  is a front elevation view of the control unit of  FIG. 2 , with the door opened;  
         [0019]      FIG. 4  is a simplified flowchart illustrating diagrammatically the various components and logic implemented in a preferred electronic control unit suitable for use in the light-activated mist sprayer system of the invention;  
         [0020]      FIG. 5  is a simplified flowchart illustrating diagrammatically the various components of a preferred electrical power supply for use in the light-activated mist sprayer system of the invention;  
         [0021]      FIG. 6   a  is a circuit diagram depicting electronic circuitry suitable for use in the light sensing and discrimination section of the electronic control unit of the invention;  
         [0022]      FIG. 6   b  is a circuit diagram depicting electronic circuitry suitable for use in establishing an electrical power supply for the various electrical components of the invention;  
         [0023]      FIG. 6   c  is a circuit diagram depicting electronic circuitry suitable for use in the pump activation and timer portion of the electronic control unit of the invention; and  
         [0024]      FIG. 6   d  is a circuit diagram depicting an antenna and electronic circuitry suitable for use in receiving a pump activation signal from an optional wireless remote transmitter.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0025]     Referring to  FIG. 1 , light-activated mist sprayer system  10  of the invention preferably comprises treating fluid source  12 , electronic control unit  14 , electrical power supply  16 , ambient light sensor  18 , and array  20  of sprayer heads  28  discharging mist  30  received from fluid source  12  through tubing or conduits  34 ,  26 . System  10  is disclosed as installed in a building structure  22 , with all components except ambient light sensor  18  and array  20  being disposed inside. Ambient light sensor  18  is desirably positioned so that it is not blocked from receiving the prevailing ambient light by trees, overhangs, screening structures, or the like, although it is not necessary that it be positioned to receive direct light from the sun  24  or another light source. When positioning light sensor  18 , care should also be given to avoiding locations where flood lights, car lights, or the like, can impinge directly on the sensor, thereby impeding the ability of the sensor to monitor the prevailing ambient light conditions. Light sensor  18  will desirably generate and feed an electrical signal to electronic control unit  14  through wire  44  or, alternatively, by means of a wireless RF transmitter (not shown). It will be appreciated upon reading the disclosure that sensor  18  can be satisfactorily mounted on buildings, poles, fences, or other structures meeting the positioning criteria described above.  
         [0026]     Fluid source  12  is depicted for illustrative purposes as a container  40  comprising a liquid treating fluid  42 , which can be withdrawn from container  40  through tubing  34  by a pump  62  disposed inside electronic control unit  14  as shown and further described below in relation to  FIG. 3 . When activated, pump  62  preferably discharges the pressurized treating fluid into conduits  26 , which feed treating fluid  42  to a plurality of spaced-apart sprayer heads  28 , each of which preferably comprise a nozzle configured to spray a mist  30  comprising treating fluid  42 . As shown, container  40  is simply a reservoir for a liquid treating fluid  42 , which can, for example, be a diluted aqueous solution of a suitable insecticide, pesticide, fungicide, or the like. For most applications, container  40  will have a capacity ranging between about 2.5 gallons and about 55 gallons. Tubing  34  is preferably heavy duty, flexible polyethylene tubing and conduit  26  can also be made of polyethylene tubing, PVC pipe, or any other similarly effective material that complies with applicable regulatory codes that are applicable for the intended use and the particular treating fluid.  
         [0027]     According to an alternative embodiment, container  40  can be provided with a stirring device capable of dissolving or suspending an active ingredient comprising a finely divided solid material in the liquid. According to another alternative embodiment, container  40  or discharge line  26  can be provided with an aeration device capable of dissolving or entraining a gaseous component in the liquid. According to yet another alternative embodiment, container  40  and pump  62  can be replaced or supplemented in system  10  by another pressurized fluid source or other supplemental devices such as a pressurized water supply line flow-controlled by a solenoid valve, with an injection pump used to introduce the treating fluid.  
         [0028]     According to a particularly preferred embodiment of the invention for residential outdoor use, array  20  will desirably comprise from about 15 to about 60 sprayer heads  28  spaced from about 10 to about 20 feet apart. Beneficial advantages are achieved if sprayer heads  28  are positioned from about 6 to 10 feet above ground level. Conduits  26  are desirably configured in such manner that the pressure is balanced throughout array  20  so that pump  62  ( FIG. 3 ) can supply treating fluid  42  to each sprayer head  28  at a pressure ranging from about 70 to about 160 psi, and most preferably about 130 psi. Each sprayer head  28  preferably further comprises a normally closed, no-drip valve and a spray nozzle made of brass, stainless steel or a suitable polymeric material that is chemically resistant to the composition of treating fluid  42  and that is able to withstand pressures within the intended operating ranges. The flow rate through each nozzle will preferably be about 0.6 gpm, although it will be appreciated that both higher and lower flow rates can be used effectively in the operation of sprayer system  10 .  
         [0029]     Electrical power for sprayer system  10  is preferably supplied by 110V or 220V line current fed from conventional outlet  38  through power cord  36  to electronic control unit  14 . Although it is intended that operation of pump  62  of sprayer system  10  is to be initiated primarily on the basis of inputs received from ambient light sensor  18 , electronic control unit  14  preferably further comprises a start/stop switch  61  that is readily accessible on the front of unit  14 , as discussed below in relation to  FIG. 2 , and functions as a manual override. Electronic control unit  14  also preferably comprises an RF antenna and receiver circuit capable of activating pump  62  upon receipt of a radio signal from optional remote transmitter  32 .  
         [0030]     Referring to  FIGS. 2 and 3 , electronic control unit  14  preferably further comprises a housing having top wall  72 , bottom wall  74 , side walls  76 ,  78  and back wall  80 . Front door  46  is preferably attached to side wall  76  by hinges  48 ,  50 . Fasteners  52 ,  54  are preferably provided to secure door  46  to side wall  78  when closed, and cooperatively aligned tabs  64 A,  64 B are provided for use in locking control unit  14  if desired. The housing for electronic control unit  14  is preferably made of metal or a suitable polymeric material, and is preferably weather-tight, although moisture seals are not shown in the drawings. Printed circuit board  66  is desirably installed inside door  46  so that LEDs  56 ,  57 ,  58  and  59  are visible from the front through door  46 . LEDs  56 ,  58  are preferably red and green, respectively, and indicate whether electrical power to control unit  14  is on or off. LEDs  57 ,  59  are also preferably red and green, respectively, and indicate whether pump  62  is on or off. Switches  60 ,  61  are preferably push-button switches. Switch  60  turns the electrical power on or off and switch  61  is a manual override switch that turns pump  62  on or off independently of light conditions. Transformer  68  is a step-down transformer that is preferentially integrated into PC board  66 , although it will be appreciated that a stand-alone transformer can likewise be included in electronic control unit  14  if desired. The housing of electronic control unit  14  preferably further comprises weather-tight connectors for receiving electrical power cord  36 , light sensor wire  44  plugging into jack  70 , and inlet and outlet connections for tubing  34  and conduit  26  to pump  62 . The electrical connections and circuitry inside a preferred embodiment of electronic control unit  14  are shown in greater detail in  FIGS. 6   a - 6   d,  and are discussed below. It should be understood that  FIGS. 2 and 3  are presented for illustrative purposes only, and that the configuration and arrangement of components within electronic control unit  14  can vary substantially from that shown within the scope of the invention.  
         [0031]      FIGS. 4, 5  and  6   a - 6   d  of the drawings are provided to illustrate preferred logic and circuitry useful in electronic control unit  14  of system  10 , although it should be appreciated that other similarly effective circuitry and components can likewise be used in implementing the operational objectives of mist sprayer system  10 .  FIGS. 4 and 6   a  depict a preferred embodiment of light level discrimination section  84  of electronic control unit  14 , in which an electronic signal received from light sensor  18  ( FIG. 1 ), a conventional, commercially available device, is received into optical coupler U 1 . The signal is then split and fed through two parallel hysteresis detectors to insure that pump  62  is not activated by transient signals attributable to stimuli other than a gradual darkening or lightening of ambient light to a predetermined “trigger” level. So-called “dusk” and “dawn” discriminators U 4  then compare the signal being received from light sensor  18  to predetermined signal values consistent with “dusk” and “dawn” ambient light conditions. Parallel nand gates receive the signals from the discriminators, and assuming that the pump start criteria has been met, signal pump controller module  86  to start pump  62 . Optionally, a manual override push button switch SW 2  is provided for use in manually starting pump  62  at a time other than as determined by light level discrimination module  84 .  
         [0032]     Referring to  FIGS. 5 and 6   b,  power supply module  90  preferably comprises a 110 volt (or 220 volt) AC input current, a step-down transformer to reduce the current to 12V, a rectifier to convert the 12V from alternating to direct current, a filter and a regulator. The 12V DC current is then fed to the circuitry on PC board  66  ( FIG. 3 ) and 110 volt AC line current upstream of the transformer is desirably fed to pump  62  ( FIG. 3 ) as shown in  FIG. 6   c.  An on/off power switch SW 1  ( 60  in  FIG. 2 ) and fuse F 1  are desirably provided between the inlet power plug P 2  ( FIG. 6   b ) and transformer  68  ( FIG. 3 ).  
         [0033]     Referring to  FIGS. 4 and 6   c,  pump start module  86  preferably comprises a misting duration selector, a misting duration timer, and a controller for the AC pump  62  ( FIG. 3 ). Referring to  FIG. 6   c,  the desired duration of each pumping cycle is set using SW 3 . The pump controller preferably uses triac Q 2  to initiate the pumping cycle upon receipt of an electronic signal from light level discrimination module  84 , the usual operational stimulus; or from manual override switch SW 2  ( FIG. 6   a ); or from the RF remote receiver module  88 , described below in relation to  FIGS. 4 and 6   d.    
         [0034]     Referring to  FIGS. 4 and 6   d,  RF remote receiver module  88  is preferably provided as part of PC board  66  ( FIG. 3 ) in case the user desires to have the capability of manually initiating a pumping cycle of operation using an optional remote transmitter  32  ( FIG. 1 ). This might occur, for example, if a “bug problem” is experienced during a particular time other than at dusk or dawn, or if system  10  is being used, for example, as a cool-water mist dispensing system during an outdoor activity at a time between dusk and dawn. Remote receiving unit  88  preferably comprises an antenna and pin selectors for synchronizing the receiver to the remote transmitter unit. Remote receiving unit  88  is powered by 12V direct current received from power supply module  90  as discussed above.  
         [0035]     Other alterations and modifications of the invention will likewise become apparent to those of ordinary skill in the art upon reading this specification in view of the accompanying drawings, and it is intended that the scope of the invention disclosed herein be limited only by the broadest interpretation of the appended claims to which the inventors are legally entitled.