Abstract:
A dosing apparatus for the delivery of a substance in discrete form comprises a conveying element in which the discharge end thereof is a close fit in a discharge bushing thereby to ensure that the correct dosage of substance is discharged on a consistent basis.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    Benefit of U.S. Provisional Application for patent Ser. No. 61/344,925, filed on Nov. 18, 2010, which is enclosed herein by reference, is hereby claimed. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to dosing apparatuses and methods, and is more particularly concerned with such an apparatus for automatically, or manually, dosing powder, or granular or other substances in discrete form. 
       BACKGROUND OF THE INVENTION 
       [0003]    It is well known in the art to provide apparatus for the delivery of such materials as mentioned above at predetermined rates, namely in prescribed dosages, in for example the chemical or pharmaceutical industries where consistent accuracy is an important requirement for their processes. 
         [0004]    Various types of dosing apparatus have been proposed and include inter alia those employing pocketed rotors, or screw feeders in either the vertical or horizontal orientations feeding particulate substances in granular, pulverulent or generally discrete form continuously or intermittently as demanded by the relevant processes. 
         [0005]    One of the problems attendant upon the usage of conventional apparatus is in maintaining the accuracy requirement in view of the predisposition of the driving elements to become contaminated and in so doing to affect the quantitative performance of the apparatus on a temporal basis. Accordingly, the efficacy of the apparatus is compromised, as is the process for which it is being employed. 
         [0006]    Accordingly, there is a need for an improved dosing apparatus. 
       SUMMARY OF THE INVENTION 
       [0007]    It is therefore a general object of the present invention to provide an improved dosing apparatus. 
         [0008]    An advantage of the present invention is that the dosing apparatus provides for consistency of delivery rates in the absence of any significant variation in quantity. 
         [0009]    Another advantage of the present invention is that the dosing apparatus is simple in construction and operation. 
         [0010]    A further advantage of the present invention is that the dosing apparatus has easily replaceable parts and its adjustment is facilitated thereby. 
         [0011]    Still another advantage of the present invention is that the dosing apparatus provides for variations in the manner of dosage delivery. 
         [0012]    Yet another advantage of the present invention is that the dosing apparatus is intended and capable of continuous operation, as 24 hours a day, 7 days a week. 
         [0013]    According to the present invention, there is provided a dosing apparatus comprising a reservoir for a substance in discrete particulate form, the reservoir for the substance having an inlet for the introduction of the substance thereto and an outlet for the egress of the substance therefrom, a conveying element adapted to convey the substance in predetermined dosages from the reservoir to the outlet thereof for delivery therefrom, a discharge end of the conveying element being held within a bushing defining a seal in use adapted to allow the discharge of the predetermined dosages as aforesaid from the reservoir and to prevent the egress therefrom of any inadvertent additional substance affecting the accuracy of the dosages, a motor for driving the conveying element, and a means for programming the required performance of the motor. 
         [0014]    Adjustment means may be provided for the conveying element to ensure proper alignment thereof in the bushing. The adjustment means may consist of a simple slide arrangement at each end of the conveying element, suitable securement being effected as necessary. 
         [0015]    The bushing may be of any desired configuration as may be dictated by the substance being conveyed in the predetermined dosage. 
         [0016]    The conveying element may be in the form of an auger or worm the flight of which is a close fit in the bushing to the extent that the interaction in use of the rotating flight and the bushing seals the element to allow the delivery of only the substance conveyed by the flight of the element and to prevent the passage of any of the substance that may have adhered unintentionally to the exterior surface of the flight. Accordingly the delivery rate is maintained at an accurate predetermined level in the absence of any appreciable variation thereto. The bushing thus provides a barrier to unwanted and contaminant flow of the substance into the prescribed dosage. 
         [0017]    The apparatus may also provide a receptacle for the dosed delivery disposed adjacent the outlet. 
         [0018]    The delivery rate for the dosing apparatus may be selected at any level, namely by minute, by hour or daily as desired, the programming means being adapted to effect such control accordingly. 
         [0019]    Other objects and advantages of the present invention will become apparent from a careful reading of the detailed description provided herein, with appropriate reference to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    Further aspects and advantages of the present invention will become better understood with reference to the description in association with the following Figures, wherein: 
           [0021]      FIG. 1  is a simplified front perspective view of a dosing apparatus in accordance with an embodiment of the present invention; 
           [0022]      FIG. 2  is a sectioned front perspective view of another embodiment with certain parts removed for the sake of clarity; and 
           [0023]      FIG. 3  is a sectioned front elevation of the embodiment of  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0024]    With reference to the annexed drawings the preferred embodiments of the present invention will be herein described for indicative purpose and by no means as of limitation with like numerals of reference being employed for like parts in differing embodiments of the invention or its details. 
         [0025]    Referring first to  FIG. 1 , there is shown an exterior view of one embodiment of dosing apparatus  1  including a housing  2  encasing a reservoir (not shown) with an inlet conduit  4  fed through a tube  5  from an elevated hopper  6 . A receptacle  8  is illustrated in ghosted outline and serves to receive dosed deliveries of a substance from the reservoir, the deliveries being effected by a conveying element (not shown) which engages a bushing  10  in the outlet  12  of the reservoir. 
         [0026]    Turning now to  FIGS. 2 and 3  a second embodiment of dosing apparatus  21  is illustrated and comprises a housing  22  defining a drive chamber  23  enclosing a motor  25  controlled in programmable fashion by a programmer (not shown), such as using a potentiometer or the like. The motor  25  is coupled to and is adapted to drive a conveying element  30 , which extends through a reservoir  32  at the relatively lower end thereof adjacent its sloping base  33 , which is provided with a plugged drain  35 . The reservoir  32  is defined between two vertical compartmentalizing walls  34 ,  36  each of which is appropriately pierced as at  38 ,  40  respectively to provide a mounting zone  39 ,  41  for the conveying element  30 . The conveying element  30  is held at each end thereof in a bushing  50 ,  51  providing a wiping seal to give a tight fit for the drive end and the discharge end of the element. The bushings  50 ,  51  are held in a mounting block  52 ,  54  respectively each of which is adjustable through the agency of a pin and slot arrangement  56  securable in position by the application of pressure provided by wing-nuts  60  or the like. A receptacle  62  for the reception in use of dosages of substance delivered by the conveying element  30  through the outlet bushing  51  is located contiguous with the reservoir  32 . The receptacle  62  has a discharge outlet  63  in its sloping base  65 . 
         [0027]    The conveying element  30  is in the form of an auger  30 ′ with a scrolled flight  31  which in use serves to move and thus convey the substance within the reservoir  32  to the outlet  12 . 
         [0028]    In operation, a substance in discrete form, for example powder or granules, is held in the hopper  6  and gravitationally feeds through the tube  5  into the reservoir  32  where the substance is supported by the sloping base  33  and between the walls  34 ,  36 . Actuation of the motor  25  in accordance with a programmed dosing regime on a temporal basis, e.g. g/min, g/hr, is instigated with the result that the conveying element  30  rotates and in so doing its flight  31  picks up the substance and scrolls it towards the outlet bushing  51 . It will be understood by the skilled addressee that since the auger  30 ′ lies and rotates within the body of the substance in the reservoir, the outer surface of the flight  31  is in contact with that substance and may attract particles which are carried thereby towards the outlet bushing  51 . However, in view of the tight fit of the discharge end of the conveying element  30  within its bushing  51 , the particles so attracted are in effect barred from entering the outlet bushing  51  and thus the predetermined dosage maintains its accuracy since it is not contaminated by inadvertent carriage of particle adhering to the outer surface of the scroll flight  31 . 
         [0029]    The substance discharged through the outlet bushing  51  descends as illustrated in  FIG. 3  into the receptacle  62  onto the sloping base  65  and falls through the discharge outlet  63  for predestined use in a relevant process which could be for example chemical or pharmaceutical in character. 
         [0030]    In an alternative application the dosing apparatus could be deployed for the controlled feeding of animals and such application may be particularly useful for intensive farming, where regular and closely monitored and accurate feeding of the animals is necessary. The programming of the motor operation may not only dictate the volume of the feed, but also the duration and number of times the motor is actuated. 
         [0031]    Although the present invention of a dosing apparatus has been described with a certain degree of particularity, it is to be understood that the disclosure has been made by way of example only and that the present invention is not limited to the features of the embodiments described and illustrated herein, but includes all variations and modifications within the scope and spirit of the invention as hereinafter claimed.