Abstract:
A self-cleaning, low-maintenance, water-saving automated animal watering device ( 10 ) is provided which includes a watering tank ( 12 ) moveable between a lower, water-full condition and an upper, water-low condition. Preferably, one end of the tank ( 12 ) is pivotally supported by a pivot shaft ( 64 ), while the other end of the tank is biased upwardly via a lower lift spring ( 72 ). The device ( 10 ) also has a water fill assembly ( 16 ) operably coupled with tank ( 12 ) to selectively fill the tank ( 12 ) when needed, and a drain valve assembly ( 18 ) also coupled with tank ( 12 ) in order to completely drain the tank ( 12 ) on a periodic basis. A control assembly ( 20 ) is coupled with at least the tank ( 12 ) and drain valve assembly ( 18 ), and is operable to actuate the drain valve assembly ( 18 ) after a predetermined number of movements of the tank ( 12 ) between the elevated and lowered positions thereof.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This Application claims the benefit of Provisional Application Ser. No. 60/912,464, filed Apr. 18, 2007. This Provisional Application is incorporated by reference herein in its entirety. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention is broadly concerned with automated, self-cleaning, low-maintenance and low-labor animal watering devices. More particularly, the invention is concerned with such watering devices and methods which provide automatic water filling of a livestock watering tank as water is consumed, as well as predictable, complete water drainage as necessary to reduce bacteria and algae buildup in the water, with only a minimum of fresh water usage for tank cleaning purposes. 
   2. Description of the Prior Art 
   Providing adequate supplies of fresh water to farm animals, particularly cattle, is a prime prerequisite for maintaining animal health, well being, and growth. This is particularly the case in confined animal feeding operations (CAFOs) where heavy water consumption by many animals tends to create poor water quality conditions. That is, animal feed particles and other debris collects in watering tanks raising the bacterial count therein to unacceptable levels and promoting undesirable algae growth. 
   It is also important that maintenance of animal watering tanks be as automated as possible CAFOs, needing only a minimum of operator intervention. In cattle feedlots, the daily labor required for continually filling, draining, and cleaning of standard, static water tanks can be excessive. 
   Another CAFO animal watering problem is excessive use of water. In many locales, water constraints are imposed upon CAFOs, and thus is its important that only a minimum amount of water be wasted. Hence, the simple expedient of daily draining of water tanks, while potentially ameliorating the bacterial count and algae growth problems, uses undue amounts of fresh water. 
   In response to these problems, it has been known to provide watering tanks equipped with a float mechanism and an associated water fill valve to control the water level in the tank. As the tank water level decreases owing to animal water consumption, the float mechanism operates to open the fill valve. Inasmuch as the tank is continuously refilled to the same level, there is a tendency for a contaminant or scum line to form, which requires significant and frequent cleaning of the tank. 
   In other designs, an upper end of a watering tank is hingedly supported with a lift spring beneath the tank at the opposite end thereof. A water inlet valve is coupled to a source of water and the tank, and linkage between the tank and inlet valve is provided. As water is consumed from the tank, the spring biases the tank upwardly until a limit is reached. At this point the valve linkage serves to open the valve to refill the tank. Such a watering device is illustrated in U.S. Pat. No. 4,347,809. However, the &#39;809 patent device does not provide for automated tank drainage, but instead requires an operator to manually open a drain. 
   U.S. Pat. No. 3,371,652 describes an automatic livestock watering device of the float control variety. This design is also equipped with an automatic drain assembly including an impeller located within the water inlet line and rotatable in response to inlet water flow. The impeller is operably coupled with a gear train carrying a lug. As the gear train rotates in response to water flow, the lug eventually contacts a toggle rod, which serves to open the drain assembly. Such a purely mechanical system is deficient because it fails to achieve predictable water drainage. Specifically, many CAFO watering sites are connected to well pumps of greatly differing water pressures, such that actuation of the impeller-operated drain assembly varies over a wide range. Furthermore, such well water is often contaminated with dirt or other debris, which can clog the impeller mechanism and prevent proper operation thereof. 
   Other prior art animal watering devices are described in U.S. Pat. Nos. 4,309,962 and 6,619,232. The systems disclosed in these patents do not provide a periodic automated drain function, and are thus deficient. 
   There is accordingly a need in the art for improved animal watering devices especially useful in CAFO contexts, and which provides automated water fill and predictable drainage with only a minimal amount of fresh water wastage. 
   SUMMARY OF THE INVENTION 
   The present invention overcomes the problems outlined above and provides improved, self-cleaning, low-maintenance, low cleaning water usage animal watering devices. Generally speaking, watering devices in accordance with the invention comprise a watering tank, and a support assembly operable to support the tank and to cause movement thereof between an elevated position corresponding to a lower water level in the tank, and a lowered position corresponding to a higher water level in the tank. Preferably, the tank is pivotally supported at one end thereof, and a lower lift spring adjacent the opposite end of the tank is positioned to bias the tank upwardly against the weight of water therein. The overall watering device further includes a selectively actuatable water fill assembly operably coupled with the tank in order to add water to the tank as necessary; the water fill assembly normally includes an electrically or mechanically operated fill valve coupled to a source of pressurized water, with a water line from the valve to the tank. Additionally, the watering device has a selectively actuatable drain valve assembly operably coupled with the tank in order to drain the tank, normally in the form of a motor or solenoid-operated gate, butterfly, or ball valve. A control assembly is operably coupled with the tank and the drain valve assembly, with the control assembly operable to actuate the drain valve assembly after a predetermined number of movements of the tank between the elevated and lowered positions thereof. 
   The invention also provides a method of maintaining an animal watering device having a water tank moveable between an elevated position corresponding to a lower water level in the tank, and a lowered position corresponding to a higher water level in the tank, and to periodically drain the watering tank. This method comprising the steps of monitoring the position of the tank and successively adding water to the tank when the tank reaches the elevated position thereof corresponding to the lower water level, and in response thereto causing the tank to move to the lowered position corresponding to the higher water level therein. The method also involves draining water from the tank after a predetermined number of the movements of the tank between the elevated and lowered positions thereof. Such tank monitoring is preferably carried out using one or more tank position sensors coupled with a control device (which may be digital or analog), and is preferably a programmable logic controller, with the control device also operably coupled with a water inlet valve and drain valve. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a preferred animal watering device in accordance with the invention; 
       FIG. 2  is an end elevation of the watering device, with side and end panels removed; 
       FIG. 3  is a plan view of the watering device; 
       FIG. 4  is a perspective view of the watering device with certain frame components cut away for clarity; 
       FIG. 5  is a longitudinal central vertical section of the device, illustrating the watering tank in its full or down position; 
       FIG. 6  is a view similar to that of  FIG. 5 , but with the tank in its up position ready to be refilled with water; 
       FIG. 7  is a vertical sectional view taken along line  7 - 7  of  FIG. 5 ; and 
       FIG. 8  is a schematic illustration of the preferred control assembly for the watering device. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Turning now to the drawings, an animal watering device  10  is illustrated. The device  10  broadly includes a water tank  12 , a tank support assembly  14 , a water fill assembly  16 , a drain valve assembly  18 , and a control assembly  20 . The tank  10  is designed to provide low-maintenance watering of farm animals, especially cattle, and particularly in the CAFO context. To this end, the device  10  provides automatic water filling as animals consume water from the tank  12 , as well as periodic, complete water drainage so as to minimize contaminant buildup. 
   In more detail, the tank  12  is in the form of an elongated, open-top vessel having a bottom wall  22 , a pair of upstanding, oblique sidewalls  24  and  26 , and end walls  28  and  30 . The bottom wall  22  is equipped with a water inlet fill opening  32  covered by a deflector  34 . Additionally, the bottom wall  22  has a drain opening  36  with a spacer  38  affixed to the underside of the bottom wall in registry with opening  36 . The end wall  28  has an upper overflow opening  40 , and an elongated, centrally located, exterior tank guide rail  42 . As best seen in  FIGS. 5-7 , the tank walls  24 - 30  cooperatively present an outwardly extending, continuous lateral lip  44 . 
   The tank support assembly  14  includes a box-like frame assembly  45  including a lower, rectangular, ground-engaging frame  46 , upstanding corner posts  48 , and three top stringers  50  of inverted L-shaped configuration supported by the posts  48  and extending around the periphery of the frame assembly  45  except for the end section adjacent end wall  30 . Oblique cross braces  52  and  54  extend between the superposed side rails of the ground frame  46  and side stringers  50  as shown. The like manner, cross braces  55  extend between the end posts  48 . The ground frame  46  also has a pair of medial, spaced apart crosspieces  56  which support a pair of central, upright, tank stops  58  surmounted by a top rail  59 , and a lift spring mount  60 . An upright valve support post  57  of inverted T-shape is attached between a cross piece  56  and the adjacent cross rail of ground frame  46  ( FIG. 4 ). As best seen in  FIGS. 2 and 46 , the ground frame  46  further supports an upstanding, obliquely oriented, generally U-shaped guide channel  62  which receives tank guide rail  42 . 
   A tank pivot shaft  64  extends between the posts  48  opposite channel  62 . The shaft  64  engages the underside of lip  44  across tank end wall  30 , and a transverse shaft hold-down lug  66  serves to secure the shaft  64  in position. Accordingly, the tank  12  is pivotal about the longitudinal axis of shaft  64 . 
   The opposite end of tank  12  is supported by means of an elongated lift arm  68  pivotally supported and extending between the tank stops  58 . The outboard end of lift arm  68  is equipped with a tank-engaging pad  70 . A coil lift spring  72  extends between spring mount  60  and the underside of lift arm  68 , and serves to bias tank  12  upwardly. 
   In normal practice, the frame assembly  45  is covered by side and end panel walls  74  and  76 , and the upper periphery of the frame  45  is likewise covered by a rectangular, U-shaped in cross section top cover  78  (see  FIGS. 1 and 3 ). An access hatch  80  is affixed to end wall  76  adjacent channel  62 , in order to allow access to the working components within the frame assembly. 
   The water fill assembly  16  includes a solenoid-operated water inlet valve  82  mounted on valve support post  57 . The valve  82  has an inlet nipple  84  adapted for coupling to a source of pressurized water (not shown), as well as an outlet nipple  86 . An elongated water inlet pipe  88  extends between nipple  86  and tank inlet opening  32  for delivery of water to tank  12 . The valve  82  has an electrically actuated on-off solenoid operator  90  controlled by assembly  20  as will be described. In other forms, use can be made of other known inlet valves such as mechanical valves, instead of solenoid valves. 
   The drain valve assembly  16  includes a motor-operated gate valve  96  which is secured to the underside of spacer  38 . The valve  96  is itself conventional, and has a reciprocal gate  98  moveable via a gear drive (not shown) between a closed position preventing the flow of water through drain opening  36 , and an open position permitting such drain flow. A suitable commercially available drain valve is commercialized by PhaseFour Industries under the designation DM20-RP Drain Master Valve. A cylindrical, upstanding tubular drain collector  100  is mounted beneath the outlet of valve  96  and presents a lowermost drain opening  102 . The valve  96  is selectively actuatable under the control of assembly  20  as will be described. 
   The control assembly  20  is schematically illustrated in  FIG. 8  and includes a digital controller in the form of a programmable logic control (PLC)  104  powered by source  106  and operably coupled with the solenoid  90  of water inlet valve  82 , and gate valve  96 . The assembly  20  further includes a tank position sensor switch  108  having a toggle arm  109 . An elongated, depending, slotted actuating arm  110  is attached to the exterior of tank side wall  24 . The slot of arm  110  receives toggle arm  109  as shown. The purpose of this arrangement is to sense the up or down position of tank  12  so that PLC  104  can operate inlet valve  82  as necessary to fill tank  12 . In addition, up or down actuation of toggle arm  109  provides count information to counter  104   a  associated with PLC  104 , so that the number of tank movements and water fills is counted In lieu of the sensor  108  and actuating arm  110 , the position of tank  12  may be sensed by a proximity sensor, a position transducer, or an optical sensor such as a laser. Alternately, a pair of limit switches could be provided at the limits of tank movement. In all instances, the goal is to determine the number of up or down tank movements and/or water fill cycles for the tank  12 , and to count these movements and/or cycles. 
   It will be appreciated that the watering devices of the invention are often used in harsh and highly corrosive environments. Accordingly, it is possible to construct the tank and frame assemblies from a variety of materials, e.g., steel, stainless steel, concrete, synthetic resin, or rubber-like materials. 
   Operation 
   The operation of watering device  10  will next be described, assuming that the tank  12  is filled with water as shown in  FIG. 5  and is therefore in its lowermost position owing to the weight of water within the tank, and the tank position sensor  108 , toggle arm  109  and actuating arm  110  are oriented to count when the tank reaches its uppermost level depicted in  FIG. 6 . Preferably, the tank holds about 20 gallons of water when fill, and the water level is approximately 2-3 inches from the top of the tank. At the lowermost water level the water at a minimum preferably covers the inlet  32  to prevent freezing in cold weather conditions; in such a case the quantity of water at the lowest level is 2-3 gallons. 
   As animals consume water from the initially full tank  12 , the weight of the water within the tank decreases, causing spring  72  to incrementally, pivotally move the tank  12  upwardly about the axis of pivot shaft  64  until the  FIG. 6  position is reached. Preferably, the tank  12  pivots through an arc of about 2.5-3, which corresponds to approximately 1.65 inches of vertical travel of the tank on the side thereof opposite shaft  64 . At this point the actuating arm  110  shifts toggle arm  109 , and such action is communicated to PLC  104  and counter  104   a . The PLC  104  then operates to open water valve  82  via solenoid  90  so that water flows through the valve and pipe  88  to fill opening  32  of tank  12 . Water is thus added to the tank  12  until the tank is again full, such action gradually pivoting the tank  12  downwardly against the bias spring  72  because of the increasing weight of water therein. It will be appreciated that the up and down movement of tank  12  is guided by means of the interfit between tank guide rail  42  and guide channel  62 . 
   This down-up cycling of tank  12 , corresponding to water depletion and subsequent water addition thereto, continues for a predetermined number of cycles, typically around  10  cycles. When the predetermined number of cycles is recorded in counter  104   a , the PLC  104  operates gate valve  96  in order to completely drain the tank  12 . During this sequence while the drain valve is open, the inlet valve  82  is again actuated to fill the tank  12 , thereby flushing debris and contaminants from the tank. Thereupon, the drain valve is closed to refill the tank  12 , and the counter  104   a  is reset to zero so that the process repeats itself. In preferred practice, tank drainage occurs when the water level therein is at the lowest level illustrated in  FIG. 6 . This serves to minimize the amount of fresh water used during tank drainage. 
   It will of course be appreciated that the device  10  could be operated in the reverse fashion, i.e., the sensor  108  could be set to toggle when the tank  12  reaches its lowermost or water full position. 
   One operational advantage of the present invention is that the tank  12  is easily removable from the supporting assembly  14 , in order to allow easy access to all of the components beneath the tank. This facilitates repair and replacement of these components. 
   A prototype device in accordance with the invention was tested against a conventional float-type watering device by placing each device in an individual cattle feedlot pen containing approximately 30 animals. Over a 28 day period, the average water usage for the conventional device was about 280 gallons/day, whereas the prototype used approximately 360 gallons/day. The estimated amount of water drained per day for cleaning purposes was about 25 gallon for the conventional device (1 drain/day), and about 15 gallons for the prototype (3 drains/day). Accordingly, the increased water usage with the prototype was attributed to increased water consumption by the cattle, owing to access clean water at all times. Bacteria counts were performed during a five day period of the test, and demonstrated that Coliform bacteria counts were 2884 CFU/ml of water for the conventional device, and only 13 CFU/ml of water for the prototype. Generic  E. coli  counts were 127 CFU/ml of water for the conventional device, and 0 CFU/ml of water for the prototype. It is believed that these bacterial count results stem from the fact that in the conventional float-type device the water level always filled back to the same level in the tank. However, in the present invention, the water levels change within a range as water is consumed, so the build up of contaminants or scum attached to the tank walls is significantly reduced.