Abstract:
A hopper feed regulator is provided for controlling the supply of feed to a hopper efficiently without having to directly contact the feed. The assembly includes a chamber having a switch contact, lever, upper hanger, cam follower and spring biasing arrangement, a second member having a lower hanger, attached at one end to the spring biasing arrangement and a cam, and the other end from which the hopper is hung. A spring biasing arrangement pulls the first and second members together at a preset spring bias strength. As the weight of the feed gathered in the hopper increases, the lower hanger is pulled away from the chamber by compressing the spring biasing arrangement. The cam, which is attached to the spring biasing arrangement, moves axially down the chamber. The cam follower, attached to the cam switch, rolls along the cam and at a predetermined weight, pulls the lever away from the switch button, thereby disengaging the switch.

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to an apparatus for automatically dispensing granular material, and more particularly to a hopper feed regulating device for controlling the supply of feed to livestock via a feed hopper. 
     BACKGROUND 
     In order for certain domesticated animals to efficiently gain weight, it is essential to provide them with adequate feed at all times. Accordingly, the amount of feed made available to the animals must be repeatedly and accurately adjusted depending on the growth of the animals. 
     One prior art attempt at maintaining the optimum level of feed to poultry comprises using a feed cart supported on an overhead rail to transport feed through a chicken house. The cart is manually rolled along the rail to feed stations throughout the house while feed is shoveled from the cart onto the floor level. 
     With the advent of automated chicken houses, feed may be automatically conveyed from a central hopper outside the house to feed receptacles distributed throughout the house without manual labor. In order to provide feed on an “as needed” basis, a multiplicity of feed pans or stations, which are typically hung from a ceiling or upper support, are arranged in rows along the length of the chicken coop and provided with feed when empty. 
     The feed pans are each connected to a conduit that, using an auger arrangement, delivers feed to the pans when an empty condition is sensed at the feed pans. The conduit is supplied from an intermediate hopper, positioned at one end of the chicken coop. When the level of feed in the intermediate hopper drops to a predetermined level, it is then re-supplied with feed from a main feed hopper, positioned outside of the chicken coop. 
     Contact switches are generally used both to sense the level of feed in the feed pans and to signal for the supply of feed to the feed pans from the intermediate hopper as needed. Additionally, a contact switching arrangement is provided to sense when feed to the intermediate hopper is needed from the primary feed hopper or silo. 
     Referring to FIG. 1, a known contact switch arrangement or flap switch for use in the intermediate hopper is generally illustrated at  11  and comprises a hinged flap  13  which pivots back and forth along the directions of arrow A so as to make a depressible contact switch  15  turn on and off. In this arrangement, the contact switch  15  is off when depressed and is on when released. In the on position, the contact switch  15  signals a feed motor to supply feed to the hopper. 
     Typically, the switch arrangement  11  is positioned in the hopper at a height that equals the desired level of feed when the hopper is full. Positioned adjacent the hinge flap  13  is a feed supply conduit  17  which pours feed B at the hinge flap  13 . When the supply of feed to the hopper reaches the desired level in the hopper, the feed piles up in front of the flap  13  so that the weight of the pile pivots the hinge flap  13  back against the contact switch  15 , thereby pushing the switch  15  to the off position and cutting off the supply of feed. As the level of feed falls, the weight of the pile of feed at the hinge flap  13  is reduced causing the flap  13  to spring forward and release contact switch  15  to the on position, as shown in FIG. 1, so as to signal for additional feed. 
     While operationally quite efficient when used at the feed pans, the flap switch  11  tends to hang-up when used in the intermediate hopper. Constant exposure to feed causes grease to build up on the hinge flap  13 , making it difficult to spring back and release the contact switch  15  to the on position. As a result, when the flap switch  11  fails, the intermediate hopper is not supplied with feed from the main hopper and the plurality of feed pans become depleted of feed. 
     If, for example, the flap switch  11  hangs up in the middle of the night, the chickens may go without feed until the next morning. By then, the chickens are so hungry that when they are finally fed, they eat so quickly that the feed travels right through the animals without being fully digested. This results in an unacceptable conversion of feed to body weight. 
     A further deficiency of the known flap switch arrangement is its tendency to switch on and off or “bounce” at the cut off rather than letting the motor run uninterrupted until the level of feed in the hopper reaches the desired level. 
     A prior attempt at alleviating the deficiencies of the flap switch include Harkins, U.S. Pat. No. 5,389,753, which discloses a feed control switch for controlling the supply of feed to a hopper without the need to contact the feed. 
     Referring to FIG. 2, the Harkins feed control switch for supplying feed to an intermediate hopper is generally illustrated at  21 . The apparatus comprises a first tubular member  23  having a hanger  25  from which the Harkins feed control switch is suspended and a second tubular member  29  slidably moveable relative to the first member  23 , the second member  29  having a suspender  31  from which an intermediate feed hopper is suspended. A spring biasing arrangement  37 , such as a helical coil compression spring, is provided for pulling the first and second members  23  and  29  together at a predetermined spring bias strength and a switch contact surface  28  is provided at the first member  23 . An on/off switch  34  is positioned adjacent to the switch contact surface  28  and at the second member  29  so as to move with the second member, the switch  34  being in an off position when the switch  34  is at an extended position and being in an on position when the switch  34  is at a depressed position. 
     When the weight of feed in the hopper exceeds the predetermined spring bias strength of the spring biasing arrangement, the second member  29 , which carries the switch  34 , pulls away from the first member  23  causing the switch  34  to move away from and disengage the switch contact surface  28  at the first member  23 . As a result, the switch  34  moves to the extended and off position, which signals a feed motor to terminate the supply of feed to be conveyed to the intermediate feed hopper. However, as feed is removed from the feed hopper to feed the chickens, at some point the predetermined spring bias strength overcomes the weight of the feed in the hopper and the second member  29  is pulled towards the first member  23  causing the switch to engage the contact surface  28  so that the switch  34  moves to the depressed and on position, which signals for the supply of feed to the feed hopper. 
     While the Harkins feed control switch attempts to resolve the deficiencies of the flap switch, it still suffers from similar deficiencies. For example, the Harkins switch comprises an open tubular design that exposes both the spring biasing arrangement as well as the tubular members to dust and other airborne particles. Accordingly, constant exposure may cause a build up of grime that interferes with operation of the control switch apparatus. 
     A further deficiency of the Harkins feed control switch is its tendency to switch on and off rapidly causing unnecessary wear on the feed motor. The rapid switching is caused by the relatively small weight differential required in the intermediate feed hopper to trigger and untrigger the switch. The on and off repetition may result in failure of the motor, which not only results in inefficient feed conversion but also may require a costly replacement of the feed motor. 
     Therefore, there is a need in the art for an apparatus for controlling the supply of feed to a feed hopper that is not easily exposed to dust and other airborne particles. There is also a need for such an apparatus that may be implemented without causing unnecessary wear on a feed supply motor. There is still an additional need for an apparatus that is easily adjustable for different types of feed and feed hoppers having different weights and densities. 
     SUMMARY OF THE INVENTION 
     The present invention satisfies the above described needs by providing an apparatus for automatically regulating the supply of feed to a feed hopper. In general, the hopper feed regulator is suspended between a chicken house ceiling and an intermediate feed hopper. The regulator has a first upper hanger attached to the ceiling and a second lower hanger attached to the feed hopper. A bias means, such as a helical spring, is disposed between the upper and lower hangers. The upper hanger is rigidly fixed to the regulator casing, whereas the lower hanger is configured to move relative to the upper hanger in an axial direction and against the force of the spring. In addition, the regulator, which is connected to a motor, has an on/off switch assembly that is activated by the relative movement of the hangers. When the switch is turned on, the motor is activated and feed is supplied to the feed hopper. As the weight of the feed hopper decreases, the weight of the hopper causes relative movement of the hangers against the force of the spring. Once the hangers have moved past a threshold point, the switch is turned off and no further feed is supplied to the feed hopper. 
     More particularly, the spring is positioned vertically and is disposed between the upper and lower hangers to support the feed hopper with a predetermined amount of bias tension. The top end of the spring is connected to a lower hanger that extends through the bias means. The lower hanger comes out the bottom end of the spring and is used to suspend the feed hopper. Accordingly, the weight of the feed hopper compresses the spring from the top down. In order to maintain the spring in the proper vertical alignment, the spring is enclosed in a sleeve that is approximately the diameter of the spring. The sleeve is attached to the upper hanger so that the relative movement between the upper hanger and the lower hanger varies the tension on the spring. 
     An elongated cam is connected to the top end of the spring and lower hanger and thus moves with the top end of the spring and lower hanger. The cam extends through a vertical slot in the sleeve and gradually descends outwardly from the sleeve. Accordingly, the bottom end of the cam is further from the spring than the top end of the cam. 
     A switch assembly is fixed to the regulator casing adjacent to the first cam with the switch contact, or button, facing the cam. The switch includes an elongated lever that extends over the switch contact and parallel with the sleeve. The bottom end of the lever is fixed to the switch below the switch contact. The top end of the lever extends beyond the switch contact. The top end of the lever includes a wheel assembly that contacts and rolls along the cam. 
     The device described above functions in the following manner. As the feed contained in the feed hopper empties, the tension on the spring decreases causing the top end of the spring and the connected cam to rise. Because the cam extends away from the spring, cam action causes the wheel assembly to push away from the spring thereby causing the lever to engage the switch contact, (i.e., depress the switch button). The engaged condition of the switch contact causes a motor to supply additional feed into the feed hopper. As the weight increases in the feed hopper, the top of the spring along with the cam descends, which causes the wheel assembly to move along the cam surface and away from the switch contact. Once the lever has moved far enough away from the switch contact, the switch turns off and the motor stops conveying additional feed to the feed hopper. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an illustration of a known prior art contact switching arrangement using a hinge flap and contact switch to control the supply of feed to an intermediate feed hopper. 
     FIG. 2 is an illustration of a known prior art contact switching arrangement using a spring bias means to control the supply of feed to an intermediate feed hopper without the need to contact the feed. 
     FIG. 3 is a diagram of an exemplary operating environment for the present invention. 
     FIG. 4 is a front cutaway view illustrating one embodiment of the feed control switch of the present invention. 
     FIG. 5 is a back view illustrating one embodiment of the feed control switch of the present invention. 
    
    
     DETAILED DESCRIPTION 
     The present invention provides a hopper feed regulator for automatically controlling the supply of feed to a feed hopper. In one embodiment of the present invention, the hopper feed regulator is suspended between a chicken house ceiling and an intermediate feed hopper. The regulator has a first upper hanger attached to the ceiling and a second lower hanger attached to the feed hopper. A bias means, such as a helical spring, is disposed between the upper and lower hangers. The upper hanger is rigidly fixed to the regulator casing, whereas the lower hanger is configured to move relative to the upper hanger in an axial direction and against the force of the spring. In addition, the regulator, which is connected to a motor, has an on/off switch assembly that is activated by the relative movement of the hangers. When the switch is turned on, the motor is activated and feed is supplied to the feed hopper. As the weight of the feed hopper decreases, the weight of the hopper causes relative movement of the hangers against the force of the spring. Once the hangers have moved past a threshold point, the switch is turned off and no further feed is supplied to the feed hopper. 
     Having briefly described an embodiment of the present invention, an exemplary operating environment for the present invention is described below. 
     EXEMPLARY OPERATING ENVIRONMENT 
     Referring now to the drawings, in which like numerals represent like elements throughout the several figures, aspects of the present invention and the exemplary operating environment will be described. 
     With reference to FIG. 3, a diagram of an exemplary system  300  for implementing the invention is illustrated. A plurality of feeding stations suspended above the floor  303  of a chicken coop, such as feeding stations  302   a ,  302   b , . . .  302   n , are supplied with feed from an intermediate feed hopper  306  via a feed conduit  308 . A feed supply motor (not shown) is used to supply feed to the intermediate feed hopper  306  from a main hopper (not shown) through a second feed conduit  310 . 
     As shown in FIG. 3, the intermediate hopper  306  is suspended from the ceiling  312  of the chicken coop using the hopper feed regulator  400 . In addition, the hopper feed regulator  400  is logically connected to a means for supplying feed, such as a feed supply motor, which supplies feed from the main feed hopper to the intermediate hopper  310 . 
     The reader should appreciate that the weight of the feed in the intermediate hopper  306  decreases as feed from the intermediate hopper  306  is used to supply feed to the chickens. If an empty condition is determined, the hopper feed regulator  400  signals for the feed supply motor to transfer feed from the main hopper to the intermediate feed hopper  306 . In one embodiment of the present invention, a spring biasing arrangement is combined with a switch assembly and cam to determine whether an empty condition exists and will be further described below with reference to FIG.  4 . 
     Once the weight of feed in the intermediate hopper  306  exceeds the predetermined spring bias strength of the hopper feed regulator  400 , the regulator  400  signals the cut off of the supply of feed to be conveyed to the intermediate hopper  306 . 
     Having described an exemplary operating environment for the invention, a diagram illustrating the hopper feed regulator  400  in accordance with an embodiment of the present invention will be described with reference to FIG.  4 . 
     HOPPER FEED REGULATOR 
     The present invention is directed towards an apparatus for automatically regulating the supply of feed to a feed hopper. Referring to FIG. 4, a frontal cutaway view of one embodiment of the present invention is shown generally at  400 . The hopper feed regulator  400  comprises a casing  404  having an upper hanger  402  and two internal compartments  406  and  408 . The upper hanger  402  is provided from which the hopper feed regulator  400  may be suspended from a ceiling of a building, such as a chicken house. It should be appreciated that the upper hanger may be used alone or in combination with other means, such as rope, twine, chain, etc., to secure the hopper feed regulator  400  to the ceiling. 
     A lower hanger  430 , separate from casing  404 , is provided to secure and suspend the intermediate feed hopper  306  (FIG.  3 ). The lower hanger  430  is attached to a shaft  432 , such as a threaded bolt. The shaft  432  is inserted through a hole (not shown) in the casing  404  so that the shaft  432  may be positioned partially within chamber  406  and partially outside of casing  404 . 
     A biasing arrangement  410 , such as a helical spring, is disposed between the upper hanger  402  and the lower hanger  430  and around the shaft  432 . However it should be understood that the biasing arrangement  410  may incorporate other means for urging the lower hanger  430  upwardly in relation to the upper hanger  402 . 
     The biasing arrangement  410  is provided for suspending the lower hanger  430  and feed hopper  306  (FIG. 3) at a predetermined bias strength. The predetermined bias strength is set so that the weight of the hopper when loaded with the desired amount of feed will overcome the bias strength of the arrangement  410  and cause a switch assembly  420  to remain in its off position. At weights substantially equaling an empty condition of the feed hopper  306 , however, the bias strength is sufficiently strong to engage the switch assembly  420 , thereby signaling the feed supply motor to supply feed to the intermediate feed hopper  306 . 
     The reader should appreciate that the chamber  406  should securely envelope the biasing arrangement  410  while allowing free axial movement, i.e., compression of the biasing arrangement  410 . In other words, chamber  406  is approximately the diameter of the spring biasing arrangement in order to maintain the spring biasing arrangement  410  in the proper vertical alignment. 
     As shown in FIG. 4, the opposing end of the lower hanger  430  and shaft  432  is fixed to the top of the biasing arrangement  410 . In one embodiment of the present invention, a flat washer and screw assembly  412  may be used to fasten the shaft  432  to the top of the biasing arrangement  410 . The shaft  432  and lower hanger  430  are configured to move in an axial direction relative to the upper hanger  402  and against the force of the biasing arrangement  410 . In other words, the biasing arrangement  410  is positioned vertically to support the intermediate feed hopper  306  (FIG. 3) with a predetermined amount of tension so that the relative movement between the upper hanger  402  and the lower hanger  430  varies the tension on the bias arrangement  410 . 
     In addition, an elongated cam  424  is fixed at the top of the biasing arrangement  410  and moves with the flat washer and screw assembly  412  in the axial direction relative to the upper hanger  402  and against the force of the biasing arrangement. The cam  424  extends away from the shaft  432  and into chamber  408  through a vertical slot (not shown) running in the same axial direction as the shaft. The vertical slot must extend enough of the length of chamber  406  to allow the cam  424  to move freely with the axial movement of the flat washer and screw assembly  412 . From the vertical slot, the cam  424  curves and gradually extends downwardly into chamber  408 . Accordingly, as shown in FIG. 4, the detached end of the cam  424  is progressively further from the vertical slot as the cam extends into the chamber  408 . 
     The hopper feed regulator  400  further comprises a side mounted switch assembly  420  in chamber  408 . The switch assembly  420 , which is logically connected to a feed supply motor, signals the feed supply motor to supply feed to the intermediate feed hopper  306  (FIG. 3) when a switch assembly button  422  is in the depressed position. Alternatively, the switch assembly  420  signals the feed supply motor to discontinue supplying feed to the intermediate feed hopper  306  (FIG. 3) when the switch assembly button  422  is in the released position. 
     As shown in FIG. 4, the switch assembly  420  is mounted parallel to the shaft  432  with the switch assembly button  422  facing the shaft  432 . The switch assembly  420  includes a lever  428  that extends over the button  422  and runs parallel to shaft  432 . One end of the lever  428  is affixed to the switch assembly  420  at a position below the button  422 . The opposing end of the lever  428  extends beyond the switch assembly button  422  and includes a wheel assembly  426  that contacts and rolls along the cam  424 . 
     The device described above functions in the following manner. As the feed contained in the intermediate feed hopper  306  (FIG. 3) empties, the reducing weight of the hopper  306  (FIG. 3) causes relative movement of the hangers  402  and  430  by means of the opposing tension of the biasing arrangement  410 . In other words, the tension on the biasing arrangement  410  decreases causing it to decompress or elongate. Accordingly, the top end of the biasing arrangement  410 , which is also connected to the cam  424 , will rise in the axial direction. Because the cam  424  curves away from the biasing arrangement  410 , as the cam rises with the top of the biasing arrangement, the wheel assembly  426  rolls along the rising cam and pushes the lever  428  away from the biasing arrangement. 
     It should be understood that as the lever  428  pushes away from the biasing arrangement  410 , the lever depresses the switch assembly switch button  422  thereby engaging the feed supply motor. More particularly, once the rising cam  424  sufficiently pushes the wheel assembly  426  and lever  428  to overcome the button throw of switch assembly button  422 , the switch assembly  420  signals the feed supply motor to begin supplying feed to the intermediate feed hopper  306  (FIG.  3 ). The button throw is defined as the distance of travel between the on and off positions of switch assembly button  422 . 
     As feed is supplied to the feed hopper  306 , the process described above operates in reverse manner. Accordingly, once the weight of the intermediate feed hopper  306  sufficiently compresses the biasing arrangement  410 , the switch assembly button  422  is released and no further feed is supplied to the hopper  306 . More particularly, as the weight of the feed hopper  306  increases, the top of the biasing arrangement  410  along with the cam  424  descends axially, compressing the biasing arrangement. As the cam  424  descends, the wheel assembly  426  rolls along the surface of the cam  424 , which relaxes the lever  428 . Once the lever  428  travels the distance equaling the button throw, the switch assembly  420  signals the feed supply motor to stop conveying additional feed to the feed hopper  306 . 
     In another embodiment of the present invention, the hopper feed regulator  400  may be easily adjustable as to the amount of feed required to trigger and release the switch assembly button  422 . For example, referring now to FIGS. 4 and 5, one embodiment of an adjustable hopper feed regulator  400  will be described. A vertical slot  502  is shown in the back casing of the chamber  408  and running parallel with the shaft  434 . The switch assembly  420  is mounted inside chamber  408  using two washer and screw assemblies  504   a  and  504   b . The two washer and screw assemblies  504   a  and  504   b  may be loosened to slide the switch assembly  420  up or down the vertical slot  502 . A plastic sheath (not shown) may also be included to cover the vertical slot  502  and protect chamber  408  from accumulating airborne particles. 
     Accordingly, in order to set the feed hopper regulator  400  so that a selected amount of feed is consistently supplied to the feed hopper  306  (FIG.  3 ), the washer and screw assemblies  504   a  and  504   b , which hold the switch assembly  420  to chamber  408 , is released and moved down (i.e., engaged) so that a supply of feed is provided to the feed hopper 6 . When a desired quantity of feed is furnished to the feed hopper  306 , the switch assembly  420  is slid up and secured so that the switch assembly button  422  is in the released position. In this fashion, the quiescent point of operation of the feed hopper regulator  400  is set so that the desired amount or weight of feed supplied to the feed hopper  306  is always delivered to the feed hopper. 
     In one embodiment of the present invention, the cam  424  has an approximate slope of −8. The reader should appreciate that alternative embodiments may comprise different and varying slopes depending on the type of switch, length of switch button throw, weight of the intermediate feed hopper, and the weight and density of the feed. 
     Although the present invention has been described above with particular reference to poultry farming, it should be understood that alternative embodiments utilizing material other than chicken feed will become apparent to those skilled in the art to which the present invention pertains without departing from its spirit and scope. In addition, while the present invention has been described with particular reference to its preferred embodiments, it should be understood that many variations and modifications will now be obvious to those skilled in that art, and it is preferred, therefore, that the scope of the invention be is defined by the appended claims rather than the foregoing description.