Abstract:
An automatic dispenser capable of delivering accurate quantities of fodder and minimizing waste is disclosed, which dispenser includes a closing mechanism having a plate that scrapes against a wall of the dispenser as the closing mechanism is actuated to reduce the build-up of fodder on the wall of the dispenser.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to an automatic dispenser, primarily for the dispensing of fodder, comprising a receptacle having an outlet opening at the bottom, and a closing mechanism which can be activated from the outside, for example by an animal. 
     Such a dispenser is known from GB patent application No. 2 283 897. 
     This known automatic dispenser has the drawback that a bridging effect easily occurs in the material to be dispensed between the internal walls of the receptacle. The automatic dispenser is thus not self-discharging. Furthermore, it cannot dispense in the desired quantities, it takes up a lot of space in an animal&#39;s feeding trough, and it is not service-friendly. 
     Another automatic dispenser is known from EP patent application No. 0 469 192 where the closing mechanism consists of two “inverted” cones mutually connected by a rod. This closing mechanism can be moved into all possible oblique directions, it presents the risk that it will get stuck in the open position, and it cannot dispense accurately. Only fodder positioned directly over the closing mechanism will be dispensed. The remaining fodder will therefore become old and thicken in the receptacle, where it will be the cause of bridge formation. 
     SUMMARY OF THE INVENTION 
     It is the purpose of the present invention to describe an automatic dispenser without the drawbacks of the known automatic dispenser. 
     This can be achieved by giving the automatic dispenser a shape as stated in the characterizing part of claim  1 . 
     The automatic dispenser according to the invention delivers smaller quantities than the known dispensers, and therefore has less waste. When the closing mechanism moves upwards there is a scraping action along the back wall of the receptacle, and the fodder moves in the direction from the receptacle&#39;s back wall towards the front wall. It is thus always the lowest fodder in the receptacle that is dispensed. 
     The fodder is set in motion so that there will be no bridging in the receptacle, and fodder will not come out until the animal releases the closing mechanism. The dispensed quantity is very accurate, and there is no waste. 
     Claim  2  deals with a special embodiment of the lowest part of a receptacle for an automatic dispenser according to the invention. 
     The embodiment according to claim  3  ensures that the lowest part of an automatic dispenser according to the invention takes up the least possible space. 
     Claim  4  deals with a preferred embodiment of a closing mechanism for an automatic dispenser according to the invention. 
     The arrangement described in claim  5  ensures that the closing mechanism closes the outlet opening in both the lowest and the highest position. 
     Claim  6  describes how the dispenses quantity can be adjusted. 
     Claim  7  describes how an air cushion can be formed at the top of the receptacle. The pressure on the closing mechanism will thereby be lower so that less force is needed to raise the closing mechanism. 
     The invention is explained in detail below with reference to the drawing in which 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a cross-section through an automatic dispenser according to the invention in which the closing mechanism is in its upper position, 
     FIG. 2 is an illustration corresponding to the one shown in FIG. 1 in which the closing mechanism is in its lower position, 
     FIG. 3 in an illustration corresponding to the one shown in FIG. 1 in which the closing mechanism is in its midway position, 
     FIG. 4 shows an illustration corresponding to the one shown in FIG. 1 in which the closing mechanism is in its upper position, and where the closing mechanism is mounted in the automatic dispenser&#39;s receptacle or house by two different pins, 
     FIG. 5 is a sectional view at I—I in FIG. 1, 
     FIG. 6 is a perspective view of a closing mechanism for an automatic dispenser according to the invention, 
     FIG. 7 is a larger scale side view of a closing mechanism, 
     FIG. 8 is a smaller scale view of a partial section through an automatic dispenser according to the invention, and a belonging trough, 
     FIG. 9 is a bird&#39;s eye view of the automatic dispenser, and 
     FIG. 10 is a worm&#39;s eye view of the automatic dispenser, 
     FIG. 11 is a larger scale view of the lower part of an automatic dispenser according to the invention according to an embodiment for the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     An automatic dispenser consists of a receptacle  1 , which at the bottom has an outlet opening  2  and a closing mechanism  3 , which can be activated from the outside. 
     According to the invention the lower part of the receptacle  1 , which co-operates with the closing mechanism  3 , has two vertical side walls  4 , FIG. 5, a vertical back wall  5 , FIG. 1, and a front wall which at the bottom has a vertical part  6  with a height of a 1 , which at its top continues as an oblique part  7  at an angle of v2 which is less that 90° to the horizontal. The width b of the outlet opening  2  is preferably larger than the depth d, FIG.  10 . Each of the side walls  4  extends at the bottom for a length of a 2  below the outlet opening  2 , thus forming a lug  8  on each side of the receptacle  1 . 
     As shown in FIGS. 6 and 7 a closing mechanism  3  for an automatic dispenser according to the invention consists, for example, of a curved bottom member  9 , which by means of - in its not mounted position - a vertical member  10  is connected to a top plate  11 , which forms an angle v3, which preferably is less than 90° to the member  10 . The top plate  11  protrudes a distance el on the front side  12  of the member  10  and a distance e2 to the rear of the back side  13  of the member  10 . The top plate  11  is approximately of the same width as the inside distance b between the two side walls  4  in the receptacle  1 . 
     The closing mechanism  3  is embodied with two supports  14  fastened to the back wall  13  of the member  10  and the upper face  15  of the bottom member  9 . Each support  14  is embodied with an oblique guide groove  16 , which forms an angle v4, which preferably is less than 90° to the horizontal. 
     The closing mechanism  3  is mounted in the receptacle  1  by means of a transverse rod  17 , which is carried through a hole  18  in each of the lugs  8  on the side walls of the receptacle  1  and the grooves  16  of the supports  14 . 
     The holes  18  are located and the guide grooves shaped and located so that the rear edge  19  and the front edge  20  of the top plate  11  rest against the inside of the back wall  5  and the front wall  7 , respectively, in the receptacle  1  when the closing mechanism  3  is in its lower position, and the front side  12  of the member  10  rests against the foremost inside edge  21  of the outlet opening  2 , and the rear edge  19  of the top plate  11  rests against the inside of the back wall in the receptacle  1 , when the closing mechanism is in its upper position. 
     When the closing mechanism is in its lower position the member  10 , as shown in FIG. 2, is approximately vertical, whereby the cross-section of the outlet at the bottom is at least as large as further up. 
     When the closing mechanism  3  is moved upwards the plate  10  will be forced by the overlying fodder in the direction towards the back wall  5  of the receptacle  1  so that the edge  19  of the plate  11  exerts a scraping action on the back wall  5 . At the same time the inclination vl of the top plate  11  during the closing action of the closing mechanism is altered. A pumping action then causes the fodder above the plate  11  as shown by arrows in FIG. 3 to be pushed in the direction from the back wall  5  towards the front wall  7 . It is therefore always the lowest fodder in the receptacle  1  that is dispensed, and bridging caused by old, thickened fodder is avoided. 
     When the closing mechanism  3  is in its upper position as shown in FIG. 1 fodder is admitted from the receptacle  1  through a gap  22  between the front edge  20  of the plate  11  and the wall  7  to a space  23  delimited between the front side of the closing mechanism  3  and the walls  4  and  7  of the receptacle  1 . 
     When the closing mechanism  3  is in its lower position as shown in FIG. 2 the quantity of fodder contained in the space  23  is dispensed at the bottom. 
     As shown in FIG. 4 the supports  14  can be embodied with additional holes  18  in a staggered vertical and horizontal direction. The figure shows the position of the closing mechanism fully drawn when the pin  17  is inserted through one hole, and dotted when the pin is inserted through another hole. When the shaft is inserted through another hole, the volume of the space  23  is altered and thus also the dispensed quantity. 
     As shown in FIG. 11 the holes  18  can also be embodied as grooves  26  in the supports  14  and can have the shape of an angle. In an area outside the groove  26  the supports  14  can have a recess  27  into which can be placed a steel plate  18  with a hole  18  opposite the groove. When the plate  28  is laterally reversed or arranged in a horizontal instead of a vertical recess there will be a new hole  18 , and consequently an altered quantity is dispensed. 
     As shown in FIG. 8 the top of the receptacle  1  can be closed by a cover  24 . The fodder is charged into the receptacle through a pipe  25  which is taken a short distance h down into the receptacle. This has the effect that an air vacuum is created in the top of the receptacle, whereby the pressure on the closing mechanism is reduced. 
     The automatic dispenser can be used for the dispensing of material other than fodder. 
     The shown and described automatic dispenser is only an example serving to illustrate the invention. Within the scope of the invention it is possible to imagine various modifications. For example, the closing mechanism might incorporate springs to activate the closing mechanism in the direction towards an open or closed position.