Patent Abstract:
A livestock cooling system creates an environment for protecting the health and productivity of animals, particularly dairy cows. One or more cooling fans are connected to programmable oscillation means, enabling the herds man to program fan oscillation according to the location of the livestock. Water is injected under high pressure into the air stream of the fans to create a fog. The system is also programmable according to various environmental conditions, including temperature, humidity, and wind velocity. The pressure and volume of the injected water are programmable and may be adjusted by the controller according to the observed environmental conditions. The disclosed system provides a cool and healthy environment for livestock, where the environment is programmed to track the animals according to the time of day and the location of shade.

Full Description:
BACKGROUND OF THE INVENTION 
     The present invention generally relates to devices and systems for sheltering livestock and more specifically to a programmable system for efficiently using evaporative cooling devices to create an environment which protects the health and productivity of the animals. 
     It is known in animal agriculture to cool livestock with evaporative cooling by wetting the animal and then drying the animal through mechanical ventilation or via natural ventilation. Alternatively, lowering the temperature of the environment will also cool animals if the decreased temperature may be maintained. The disclosed system provides cooling to livestock through direct evaporative cooling and also by decreasing the temperature of the livestock environment. 
     The disclosed system may deliver water to a given area without wetting the area, unlike the other known devices which wet one area continuously and usually result in wet bedding. With the disclosed system, by the time a fan oscillates back to the original zone, water previously emitted has partially or totally evaporated. The disclosed system allows the wetting-drying cycle to be accelerated or decelerated to maximize evaporative cooling given current environmental conditions. Temperature and humidity are monitored so that the maximum amount of water for evaporative cooling can be supplied to each fan under real time environmental conditions. The upper constraint on the amount of water delivered by each fan will usually be a volume of water which would wet the animal&#39;s bedding. Other environmental conditions may also be monitored, such as wind velocity, the intensity of sunlight, or the position of the sun with respect to the location of the livestock and a shading structure. 
     The disclosed system can be configured to emit water at high pressure so as to result in flash evaporation of the extremely small water particles which come into contact with any warm surface such as the skin of an animal or person. The result is a cool animal environment with little wetting of the animal&#39;s hair-coat and virtually no wetting of the animal&#39;s bedding. 
     Each fan within a fan circuit can be stopped and started in any position. The oscillation of a fan circuit is totally programmable. The oscillation of a fan circuit can be concentrated in a particular degree range at certain times of the day to increase animal comfort. The speed at which each fan circuit oscillates is programmable through the entire range of oscillation. A faster oscillation speed may be desired in areas prone to wetting, such as free-stall beds. Alternatively, slower oscillation may be desired in other areas, such as over cement alleyways. Programming can be changed at any time to meet the individual preferences of the animal herds person. 
     Water output can be varied according to a pre-programmed schedule or through constant monitoring of current environmental conditions. Current temperature, humidity and wind conditions may be monitored and water output controlled accordingly by a variable-frequency-drive on the high-pressure water pump. Water output may also be controlled by switching nozzle sizes, instead of or in addition to changing pump pressure output. In conjunction with programmable oscillation, programmable water output allows the herds person to fine tune the animal&#39;s environment for maximum economic gain and animal comfort. 
     Typical Applications of the Disclosed System 
     Dry-Lot Dairies 
     A typical dry-lot dairy application of the disclosed system is to provide a range of oscillation for a fan circuit, where the fan air stream is directed under the shade structure during those times of day when the shade, and therefore the cows, are underneath the shade structure. As the sun travels across the sky the shade produced moves away from the shade structure. The cows follow the shade away from the shade structure. The programmable nature of the disclosed system allows a fan circuit to follow the shade and oscillate in the area where cooling is needed. 
     Free-Stall Dairies 
     In a free-stall dairy application, fans within a fan circuit may be mounted at the feed lane, between the free-stall beds, or on the outer columns of the building. The mounting arrangement chosen can optimize any prevailing winds. A fan circuit may be programmed to oscillate from the outer alley of the building to the feed lane. This oscillation action completely cools the living area of the cows. A novel feature of the disclosed system is that a fan circuit may be programmed to put out more water while oscillating over the cement alleys, and less water while oscillating across free-stall beds. In addition, the speed at which a fan circuit oscillates can be decreased over the cement alleys and/or increased over the beds. This feature of the disclosed system prevents the build-up of water on the free-stall beds which can be hazardous to the health of the livestock. Wet bedding is an ideal environment for microorganism growth which can result in a cow contracting mastitis, or inflammation of the mammary gland. 
     During feeding times, fans within a fan circuit can either be parked at a fixed direction or the oscillation range of the fan circuit restricted, so the fans cool the feeding area intensively while the cows are eating and/or just after the cows return from the milking barn. 
     Saudi Style (A.K.A. Beach Barns) 
     In a Saudi Style Barn, popular in hot-dry climates such as Arizona and Mid-Eastern Countries, fan circuits mounted on the feed lanes result in effective cooling of the entire barn. Other mounting arrangements such as outer-building support posts can be utilized to take advantage of any prevailing winds. As with free-stall barns, the fans can be programmed for cooling the cows at the feed lane more intensively during feeding times and/or after milking. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a livestock cooling system which creates an environment which protects the health and productivity of the animals. The livestock cooling system comprises a structure, the structure comprising a roof connected to supporting members, at least one electrically-powered fan creating an air stream, the fan rotatably coupled to the structure, oscillation means connected to the fan for rotating the fan through a plurality of rotational positions, means for injecting water droplets into the air stream of the fan, at least one sensing device positioned to sense environmental conditions and adapted to produce a signal in response to said conditions, and input/output means for receiving the signal produced by the sensing device and outputting a signal limiting the plurality of rotational positions through which the fan is rotated. The livestock cooling system may further comprise controller means for controlling the oscillation means and the means for injecting water droplets into the air stream. The controller means comprise, in part, a plurality of sensing devices positioned to sense environmental conditions and adapted to produce a signal in response to those conditions, a position indication device to determine the rotational position of the fan, where the position indication device is adapted to produce a signal in response to the rotational position. The controller means further comprise programmable input/output means adapted for receipt and storage of input from the sensing devices and the fan position indication device, where the programmable input/output means is formed to produce an output signal based upon the input received from the sensing devices and the position indication device. Power means are adapted to receive a signal produced by the programmable input/output means, where the power means are coupled to the oscillation means for operation of the oscillation means. Pressure control means are adapted to receive a signal produced by the programmable input/output means, where the pressure control means are coupled to the means for injecting water droplets into the air stream for controlling the output pressure of the same. 
     A variety of different environmental conditions may be sensed by the sensing devices and inputted to the controller means, including temperature, humidity, wind velocity, intensity of sunlight, and the position of the sun with respect to the structure. 
     The disclosed system may comprise a single circuit of fans controlled by a local control panel, or a plurality of fan circuits, wherein each circuit is controlled by a local control panel, and each local control panel is in communication with a master control panel. A remote supervisory station may be included in this system to send and receive signals to and from the master control panel, so that an entire system of fans may be monitored and/or controlled from the remote supervisory station. 
     These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an isometric view of a typical fan of the disclosed livestock cooling system. 
     FIG. 2 is a second isometric view of a fan of the disclosed cooling system. 
     FIG. 3 is a detailed view of one embodiment of a drive mechanism for fan oscillation. 
     FIG. 4 is an isometric view of one embodiment for placement of an oscillation motor and pump motor. 
     FIG. 5 shows how a plurality of fans may be programmed to oscillate in the morning. 
     FIG. 6 shows how a plurality of fans may be programmed to oscillate at mid-day. 
     FIG. 7 shows how a plurality of fans may be programmed to oscillate in the afternoon. 
     FIG. 8 is a schematic drawing showing the configuration of a typical local control panel. 
     FIG. 9 is a schematic drawing showing the configuration of a master control panel. 
     FIG. 10 is a schematic drawing showing one embodiment of the disclosed monitoring and control system. 
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Referring now specifically to the drawings, FIG. 1 shows a structure  14  having a roof  16  connected to supporting members  18 . Mounted within the structure  14 , is at least one fan  20 . FIGS. 1 and 2 show the major components of a typical fan  20  used in the disclosed system. Depending upon the particular application, a plurality of similar fans  20  may be used in the system. Each fan comprises a blade, not shown, enclosed within housing  22 , a motor  24  attached to the housing  22  for rotating the blade, a grill  26  attached to the front of the housing  22 , a mist ring  28  attached to the grill  26 , nozzles  30  connected to the mist ring  28 , a water supply line  32  for providing high pressure water to the nozzles  30 , power cable  34  for providing electrical power to the motor  24 , motor starter  36  for starting motor  24 , and mounting bracket  38 , which supports the weight of fan  20 . Mounting bracket  38  is connected to pivot arm  40  which is rotationally attached to stationary member  42 , which is attached to a supporting member  18  or other member of the structure  14 . Fan  20  creates an air stream  44  into which water droplets are injected from the nozzles  30  mounted within the mist ring  28 . Water is provided to the mist ring  28  by high pressure water line  32 . 
     Oscillation means are provided to the disclosed system which allows each fan to oscillate within a pre-programmed arc, up to a maximum of 270 degrees for the embodiment shown in FIGS. 1 and 3. Various oscillation means may be operably attached to the fan  20 , which rotate the fan through a plurality of rotational positions. In one embodiment, the oscillation means comprise a drive shaft  46 , having a first end  46 A and a second end  46 B, to which drive shaft  46  means for rotational motion are applied so as to rotate drive gear  48 . Drive gear  48  imparts rotation to pivot arm  40  by use of a chain  50  connected to free gear  52 , thereby causing oscillation of fan  20 . Drive gear  48 , which is attached to first end  46 A, and free gear  52  are supported by bearings  54 . Alternatively, chain  50  may be eliminated by directly enmeshing drive gear  48  to free gear  52  to provide direct drive. 
     Various means for applying rotational motion to drive shaft  46  are available. In the embodiment disclosed in FIG. 1, cables  56  are connected to drive shaft flange  58 , attached to second end  46 B, by drive shaft clamps  60 . Instead of using drive shaft flange  58 , it is also possible to connect cables  56  to a drum attached to drive shaft  46 . If a drum is used, it is possible to increase the maximum arc of oscillation to a value greater than 270 degrees. 
     As an alternative to cables  56 , other linkage means known in the art may be utilized, such as rods. As further shown in FIG. 1, cables  56  may extend past drive shaft flange  58  and provide rotational motion to additional drive shafts  46  causing oscillation of additional fans  20 . As shown in FIG. 4, cables  56  are connected to the shaft of oscillation motor  62  by oscillation clamps  64 . As further shown in FIG. 4, cables  56  may extend in both directions from oscillation motor  62 , so fans  20  may be placed on either side of oscillation motor  62 . 
     Oscillation motor  62  is electrically connected to the oscillation motor variable frequency drive  66 , such as a Series No. VSD07 manufactured by SQD. As depicted in FIG. 8, the variable frequency drive  66  may be located within the local control panel  68 . A programmable controller  70 , such as a IDEC Microsmart series, is also contained within the local control panel  68 . The programmable controller  70  is equipped with a central processing unit, a real time clock module, a RS 485 module, an analog input and output module, digital input modules and digital output modules. 
     The rotational position of each fan  20  is sensed by a position indication device  72 , which may be mounted either at each individual fan  20  or preferably, because fewer position indication devices  72  are required, at the oscillation motor  62  which drives a circuit of fans. The position indication device  72  is adapted to produce a signal in response to the rotation of the fan  20 , as monitored directly from the fan  20 , or in response to the rotation of the oscillation motor  62 , which will provide a signal indicating the position of each fan  20  being driven by the oscillation motor  62 . The output signal from the position indication device  72  is transmitted to the local control panel  68 . An acceptable position indication device is a series 755 encoder available through Encoder Products Corp. of Sand Point, Id., or a Rotary Cam available through Electro Cam Corp. of Concord, Ontario. 
     As an alternative embodiment to the system disclosed in FIGS. 1 and 4, a separate oscillation motor may be directly attached to each drive shaft  46 , eliminating the need for linkage means such as cables  56  or rods. In this embodiment, each oscillation motor would be electrically connected to the oscillation motor variable frequency drive  66  located within the local control panel  68 . 
     Water droplets are injected into the air stream  44  created by each fan  20 . Water is delivered to the mist ring  28  of each fan  20  through a high pressure water line  32 . Stainless steel or other corrosion resistant materials with acceptable pressures ratings are acceptable materials for construction of the mist ring  28 . A plurality of nozzles  30  are attached to the mist ring  28 . Nozzles  30  may be screwed into female connections welded to mist ring  28 , or otherwise attached. Water is delivered into high pressure water line  32  by pump  74 . Pump  74  may be a plunger pump available through General Pump of Mendota Heights, Minn. or Cat Pumps of Minneapolis, Minn. Pump  74  is driven by pump motor  76 . The pump flow rate of pump  74 , and thus outlet pressure, may be controlled by various pressure control means. The pump flow rate may be increased or decreased by controlling the revolutions per minute of motor  76  by controlling motor  76  with pump motor variable frequency drive  78 , resulting in increased or decreased output pressure. Pump motor variable frequency drive  78  may be located in local control panel  68 . Alternatively, output pressure of pump  74  may be controlled through a plurality of solenoid-activated by-pass valves  80 . The solenoids are controlled by a thermostat set within local control panel  68 , so that when required by hotter temperatures, the solenoids will sequentially close a by-pass valve  80  to increase pressure to nozzles  30 , and water volume. 
     When water droplets are injected into the air stream  44  of each fan, there is the possibility of creating a drench, a mist, or a fog, depending upon, among other factors, including environmental conditions, the volume of injected water, the injection pressure, and the droplet size. A drench showers the animal, wetting the animal to its skin, but is not normally a suitable cooling method when the animal is in its bedding area or is being milked. With a mist, the water droplets injected into the air stream  44  are smaller than with a drench, but the air becomes saturated with continued water injection, resulting in the animals and bedding becoming wet. A mist creates an undesirable water layer on the animal which acts as an insulator and retains heat. With fog, water is emitted through very small diameter nozzles  30  at a sufficiently high pressure so as to result in extremely small water particles. These water particles will flash evaporate when the particles come into contact with any warm surface such as the skin of an animal or person, resulting in a cool animal environment with little wetting of the animal&#39;s hair-coat and virtually no wetting of the animal&#39;s bedding. 
     The disclosed system generates evaporative cooling by monitoring environmental conditions with environmental sensing devices, such as a temperature probe  82  and/or a humidity probe  84 , and adjusting water pressure and water volume accordingly, and injecting water at high pressures through small diameter nozzles. The temperature probe  82  provides an analog temperature value to the local control panel  68 . Likewise, the humidity probe  84  provides an analog humidity value to the local control panel  68 . Acceptable temperature and humidity probes are available through Veris Industries, Inc. It has been found that a nozzle diameter of approximately 0.02 inches and injection pressures ranging from 500 to 1200 psi provide the desired water particle size of approximately 8 to 30 microns. The ability of the disclosed system to create a non-wetting fog is further enhanced because the oscillation of the fans  20  may be programmed as to the oscillation arc and the oscillation speed, so that the duration of water injection into a particular oscillation position of the fan  20  is programmable. 
     As shown in FIGS. 5 through 7, the plurality of fans  20  within a structure  14  oscillate together so that the air streams  44  of each fan are oriented in the same direction. Because of its ability to provide cooling fog to a particular zone at a particular time of day, the disclosed system provides the ability of the herdsman to program the system to provide a zone of comfort to livestock to the areas in which the livestock gather according to the time of day. In essence, the disclosed system creates a localized environment which is healthy and comfortable to the animals. 
     The control and monitoring stations of the disclosed system may be configured in several different ways. At its simplest, the system comprises a fan  20  or a circuit of fans  20 , an oscillation motor  62  and related controls to oscillate the fans  20 , a pump  74  for delivering water to the mist ring  28  of each fan, means for controlling the pump output pressure and volume, such as a pump motor variable frequency drive  78  or a plurality of by-pass valves  80 , and a local control panel  68  containing a programmable controller  70 , which based upon inputted values for environmental conditions such as temperature and humidity observed by the environmental sensing devices, sends output signals to control the zone of oscillation, the oscillation speed, and pump pressure to the nozzles  30 , as shown in FIG.  8 . The local control panel  68  may be configured to sequentially start each individual fan motor  24  to reduce peak demand in starting the system. 
     A master control panel  86 , shown in FIG. 9, may be linked to the local control panel  68  with RS 485 input and output devices  88 . The master control panel  86 , which contains master panel programmable controller  90 , may receive input signals from various time clocks and environmental sensing devices, such as a temperature probe  82  and a humidity probe  84 , and send output signals to local control panel  68 , and receive input signals from local control panel  68 , thus making local control panel  68  a slave to master control panel  86 . As shown in FIG. 10, a network of local control panels  68 , each local control panel  68  connected to a fan circuit, may be controlled by a single master control panel  86 , making the disclosed system adaptable for large dairy operations with a plurality of structures  14 . As further shown in FIG. 10, a remote supervisory station  92  may be connected to the master control panel  86  with an RS 232 to RS 485 converter  94 . The remote supervisory station  92  may be a personal computer platform with a Windows or equivalent operating system, using software known within the art for converting data received from the master control panel  86  to a format compatible with the PC. The remote supervisory station  92  would provide the operator whole dairy overview screens, and individual screens for the status of individual structures  14 . 
     While the above is a description of various embodiments of the present invention, further modifications may be employed without departing from the spirit and scope of the present invention. For example, the size, shape, position and/or material of the various components may be changed as desired. Thus the scope of the invention should not be limited by the specific structures disclosed. Instead the true scope of the invention should be determined by the following claims.

Technology Classification (CPC): 8