Abstract:
A livestock cooling apparatus comprising an electrically-powered fan, which is capable of oscillating 360 degrees. The apparatus may be used in conjunction with a programmable cooling system for livestock which allows each fan in the system to be programmed to sweep a designated area according to observed environmental conditions or according to the time of day. The cooling apparatus may further comprise a mist ring for injecting water into the airstream created by the fan to provide for evaporative cooling of the livestock.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This is a second continuation-in-part of U.S. application Ser. No. 09/967,678, U.S. Pat. No. 6,578,828 filed on Sep. 28, 2001, to which the inventors claim domestic priority, and which is incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention generally relates to devices and systems for sheltering livestock and more specifically to a livestock cooling fan which may be used in conjunction with a cooling system which implements programmable 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. It is also known to use fans to deliver air cooled by water to an area occupied by livestock. U.S. patent application Ser. No. 09/967,678, filed by the inventors herein, shows how fans may be interconnected or mechanically linked such that the fans oscillate together over a predetermined area for a given time of the day or for a specific set of conditions, where the system is capable of delivering cooling fog. This type of system creates an environment which is healthy for livestock, and may result in higher yields of milk for dairy cows. 
     The oscillation of a fan circuit within application Ser. No. 09/967,678 is 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. 
     However, the linkage mechanism used with the prior disclosed cooling system may include rigid linkage arms or cables which prevent each fan in the system from being capable of oscillating a complete 360 degrees. This limitation means there are “hot spots” where the fans are unable to provide cooling for the livestock. In addition, the linkage mechanisms may be overly complicated, resulting in increased cost, maintenance and/or downtime. A livestock cooling system is desired in which the cooling fans are able to oscillate a complete 360 degrees, where the connecting linkage is relatively simple. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a fan for a livestock cooling system, where the fan is capable of oscillating a complete 360 degrees through the use of simple linkage. The disclosed fan is adaptable to be used with previously disclosed cattle cooling systems which provide for programmable oscillation of circuits of fans. The disclosed fan may 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 disclosed livestock cooling apparatus comprises an electrically-powered fan, where the fan creates an air stream. The fan comprises a fan blade, a fan motor, and a fan enclosure. The fan blade is operably attached to the fan motor, and the fan blade and fan motor are mounted in the fan enclosure. The fan enclosure is attached to a fan yoke. The cooling apparatus further comprises a drive shaft having a first end and a second end. The first end of the drive shaft is coupled to the fan yoke. An attachment member attached to a first support means supports the fan enclosure. The attachment member has a top, a bottom, and an aperture extending through the attachment member from the top to the bottom. Bearing means are attached to the attachment member, where the bearing means are disposed within the aperture. The bearing means and aperture are adapted for receiving the drive shaft therethrough. A first pulley is attached to the second end of the drive shaft. Oscillation means are connected to the first pulley for rotating the fan through a plurality of rotational positions. The apparatus may include means for injecting water droplets into the air stream of the fan. 
     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 a perspective view of the disclosed livestock cooling fan. 
     FIG. 2 is a front view of the disclosed livestock cooling fan. 
     FIG. 3 is perspective view of one embodiment for placement of an oscillation motor and pump motor. 
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Referring now specifically to the drawings, FIG. 1 shows the disclosed livestock cooling apparatus  10 . The apparatus comprises an electrically-powered fan  12 , the fan comprising a fan blade  14 , a fan motor  16 , and a fan enclosure  18 . The fan blade  14  is operably attached to the fan motor  16 . The fan motor  16  and the fan blade  14  are mounted in the fan enclosure  18 . As shown in FIG. 1, the fan enclosure  18  is attached to a fan yoke  20 . The fan yoke  20  may be attached to the outsides of the fan enclosure  18  as shown in FIG. 1, so that the fan enclosure is enclosed within the fan yoke  20 . In this embodiment, the angle of the fan enclosure  18 , and therefore the angle of the air stream  22  created by the fan, may be adjusted with respect to the ground, allowing the user to adjust the direction of the air stream. The fan yoke  20  may be constructed from square or rectangular steel stock and may be configured in the U-shape depicted in FIG.  1  and FIG.  2 . 
     A drive shaft  24  is coupled to the fan yoke  20 , the drive shaft having first end  26  which is coupled to the yoke, and second end  28  to which is attached a first pulley  30 . 
     Drive shaft  24  is supported within bearing means  32 . Bearing means  32  are supported attachment member  34 , which is attached to a support means  36 . As shown in FIG.  1  and FIG. 2, the attachment member may be attached to a variety of support means, including a structural member of a livestock protective structure, such as a barn or shade structure, where the structure has a roof  38  connected to support means  36 . 
     The attachment member  34  may have a top  40  and a bottom  42 . An aperture extends through the attachment member  34  from the top  40  to the bottom  42 . The attachment member  34  may be constructed from square or rectangular iron stock. Attachment member  34  may be attached to support means  36  with U-bolts, or other suitable attachment means including bolting and welding. Bearing means  32  are disposed within the aperture of attachment member  34 , where the bearing means and aperture are adapted for receiving drive shaft  24  therethrough. 
     First pulley  30  is attached to a second end  28  of drive shaft  24 . A stop collar  44  or other retaining device is attached to drive shaft  24  above bearing means  32 , such that the stop collar  44  or retaining device engages the top of bearing means  32  to support the weight of the fan  12  and the yoke  20 . Oscillation means are connected to the first pulley  30  for rotating the first pulley  30 , the drive shaft  24 , the fan yoke  20  and the fan  12  through a plurality of rotational positions ranging up to a complete 360 degree rotation. The oscillation means may comprise an oscillation motor  46  attached to support means  36 , where a second pulley  48  is operably connected to the oscillation motor  46 , and cables  50  connect the second pulley  48  to the first pulley  30 . 
     As depicted in FIG.  1  and FIG. 2, cables  50  form looped belts, which engage any one of the several grooves on first pulley  30  and second pulley  48 . As further shown in FIG.  1  and FIG. 2, additional looped belt cables  50  may be attached to first pulley  30  and/or second pulley  48 , thereby allowing a series of fans to be driven by a single oscillation motor  46 . A third pulley  52 , attached to support means  36 , may be used to change the direction of the cables as required by the desired configuration of fans. 
     Bearing means  32  may comprise a first bearing  32 A mounted on the top  40  of attachment member  34  and a second bearing  32 B mounted on the bottom  42  of the attachment member  34 . As an alternative, bearing means  32  may comprise a single bearing disposed within the aperture of the attachment member  34 . 
     Oscillation motor  46  may be electrically connected to a variable frequency drive, such as a Series No. VSD07 manufactured by SQD. The variable frequency drive may be located within a local control panel  54 . A programmable controller, such as a IDEC Microsmart series, may also be contained within the local control panel  54 . The programmable controller may be 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. 
     As an alternative embodiment to the system disclosed in FIGS. 1 and 2, a separate oscillation motor  46  may be directly attached to each drive shaft  24 , eliminating the need for cables  50  or other linkage. 
     The rotational position of each fan  12  may be sensed by a position indication device  56 , which may be mounted either at each individual fan  12  or, because fewer position indication devices  56  are required, at the oscillation motor  46  which drives a circuit of fans. The position indication device  56  is adapted to produce a signal in response to the rotation, i.e., oscillation, of the fan  12 , as monitored directly from the fan  12 , or in response to the rotation of the shaft of the oscillation motor  46 . A position indication device  56  at either location will provide a signal indicating the rotational position of each fan  12  being oscillated by the oscillation motor  46 . The output signal from the position indication device  56  may be transmitted to local control panel  54  or to a remote panel. 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. 
     The disclosed apparatus may also comprise means for injecting water droplets into the air stream  22  of the fan  12 . One means of injecting water droplets into the air stream  22  comprises delivering water to a mist ring  58  of each fan  12  through a high pressure water line  48 . Stainless steel or other corrosion resistant materials with acceptable pressures ratings are acceptable materials for construction of the mist ring  58 . A plurality of nozzles are attached to the mist ring  58 . The nozzles may be screwed into female connections which are welded to mist ring  58 , or otherwise attached. Water is delivered into a high pressure water line  60  by a pump  62 . Included among acceptable pumps are plunger pumps available through General Pump of Mendota Heights, Minn. or Cat Pumps of Minneapolis, Minn. Pump  62  is driven by pump motor  64 . The pump flow rate of pump  62 , and thus outlet pressure, may be controlled by various pressure control means. For example, the pump flow rate may be increased or decreased by controlling the revolutions per minute of motor  64  with a motor variable frequency drive, resulting in increased or decreased output pressure. The pump motor variable frequency drive may be located in local control panel  54 . High pressure water line  60  may be equipped with a swivel to further enable the fan to rotate a complete 360 degrees. The lengths of water line  60  and the power line  66  to the motor should be sized to allow a complete 360 degree rotation. 
     When water droplets are injected into the air stream  22  of each fan  12 , 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  22  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 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 cooling apparatus may be used with systems which monitor environmental conditions with environmental sensing devices, such as a temperature probes and/or a humidity probes, which transmit a signal to process control equipment, which provides an output signal to end devices which adjust water pressure and water volume accordingly. For example, the input to the process controller from a temperature probe may indicate the need for additional fog, so the process controller provides an output signal to a variable speed drive connected to pump motor  64 , increasing pump speed so that additional water may be injected for generating fog. 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. 
     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.