Patent Document

FIELD OF THE INVENTION 
       [0001]    This invention concerns distribution of powder-like substances and particularly relates to a readily portable apparatus, and its functional process, for distributing between multiple processing stations arranged along a food processing deck, particulate food seasonings such as curry powder, sausage seasoning, lemon pepper and the like, in a substantially dust-free, fluidized-like manner. 
       BACKGROUND OF THE INVENTION 
       [0002]    In both the process food and snack food fields seasonings are applied to food products for enhancement of the consumers&#39; taste experience as well as to establish the expected flavor profile typical of the products. Frequently the seasonings are furnished to the food processor in bulk, such as in sacks weighing 35 to 50 lbs (15.8 to 22.7 kg) or more. The seasonings are in fine particle form that can be characterized as a powder and frequently the particle sizes range from about 3 microns to about 3 mm. Although there are instances where the seasoning constituents are quite uniform in particle size, there are many other instances where the constituents are quite heterogeneous ranging from large to small particles and consequently tend to segregate into distinct volumes of the small and the large particles during storage. 
         [0003]    Generally in food processing plants there are several operating lines producing products differing in sizes, shapes and flavors. Specific seasonings are associated with each of those products and are applied to the products at seasoning “stations” on the processing line. Each seasoning station includes a container or bin of some sort holding a supply of the designated seasonings from which the seasoning is dispensed. This container must be replenished from time to time during a product production run as the seasonings are dispensed on to the products. The intervals for replenishment vary and a replenishment system may stand idle during such intervals. In prior art replenishment systems it was found that during the idle intervals many of the powder like seasonings would segregate, coalesce or generally pack so tightly that to again effectively distribute them some human basic physical efforts were required such as applying blows on the sidewalls of the seasoning container, stirring using an implement or physically shaking the unit. The results of such efforts were uneven and clumps of seasonings would sometimes inadvertently be deposited on the food products which is quite undesirable. 
         [0004]    Seasoning replenishment equipment desirably should be characterized by ease of cleaning so that different seasonings may be applied to differing products using the same equipment with only insignificant seasoning “carry over.” The prior art screw conveyors, drag conveyors and bucket elevators were all difficult to clean and required large radius turns and large equipment footprints. In a food processing plant having a number of processing lines each requiring seasonings it is highly desirable to have the seasoning replenishment equipment readily portable so as to facilitate servicing the individual processing lines with ease and with a minimum of disruption or obstruction along the plant&#39;s processing deck. 
         [0005]    Working with powder-like substances such as seasonings carries the risk of injecting particulate matter or “dust” into the ambient atmosphere within the food processing plant. This is a highly undesirable condition which, if left unaddressed, will deteriorate the working environment and, indeed, may amount to an industrial offense when contravening governmental regulations concerning dean air in the workplace. The prior art pneumatic conveying systems for seasonings seemed to exacerbate this risk and were vulnerable to air leaks, hence dust leaks, within the pneumatic seasonings conveying system. The amount of dust created in a powder transfer process is exponentially related to the volume and velocity of the air used. Moreover, in pneumatic conveying systems the phase density of the conveyed stream is usually quite low given that the propulsive air is mixed with the seasonings, causing a substantial degree of segregation, and also produces dust at the outlet. By phase density we mean powder flow in pounds (kgs) per hour divided by conveying air used in pounds (kgs) per hour. On the other hand, a high phase density means a higher efficiency and lower energy costs, less segregation, less product/seasoning damage and less dust. Long recognized is that system wear in powder conveying systems increases roughly to the 2.8 power of the conveying velocity. Depending on particle friability, size and shape the damage to seasoning particles increases by roughly the same exponent. By vastly increasing the phase density and lowering the transport velocity, the wear on components and damage to the seasoning powder goes down exponentially. 
       SUMMARY OF THE INVENTION AND OBJECTS 
       [0006]    The invention in summary concerns a portable seasoning replenishment apparatus including a canister serving to contain a supply of a seasoning to be dispensed at a seasoning applying station arranged in a food processing line. The canister is portable in a rolling action to facilitate serving a plurality of processing stations. One portion of the body of the canister is equipped with a seasonings reception chamber and having reception port means and a seasonings discharge port means. Another portion of the canister body is equipped with a pneumatic chamber or plenum serving to receive a volume of pressurized air and being equipped with an air permeable member serving to emit air into the seasonings chamber at a rate sufficient to fluidize by ablating a portion of the seasonings therein most adjacent to the permeable member. The apparatus may carry its own pressurized air supply or may be connected with a supply of pressurized air within the processing plant. A flexible conduit is coupled to the seasonings discharge port for delivery of seasonings in a fluidized stream at the seasonings applying station in a substantially dust free manner. 
         [0007]    A general object of the invention is to curb and control the dispersion of dust components of food seasonings within the food processing plant during seasoning transport at the needed replenishments. 
         [0008]    Another object of the invention is to facilitate the handling of food seasonings of the type that tend to duster and sometimes segregate by transporting the seasonings in an improved and gentle manner in a continuous stream that eliminates the need to manually stir or agitate the seasonings such as when encouraging seasoning flow during the replenishing operation. 
         [0009]    Still another object of the invention is to provide for the efficient transport of powder-like substances in an improved manner that utilizes a lowered volume and velocity of the transport air thereby to reduce substantially the velocity of the substances and to minimize the disturbance of the main bulk of the substance. 
         [0010]    Yet another object of the invention is to reduce the segregation of multi-constituent powder during transport while reducing substantially the incidence of dust dispersion from the powder being moved. 
         [0011]    Still another object of the invention is to provide a seasoning replenishment system for transporting powder-like substances that is non-segregating, non harmful to fragile products, low in energy consumption, reliable, dean and safe to operate. 
         [0012]    These and other objects of the invention will become apparent from the descriptions of the preferred embodiments that follows taken in connection with the drawings illustrating the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a perspective view of the seasoning replenishment system made in accordance with and embodying the principles of the present invention; 
           [0014]      FIG. 2  is a view like  FIG. 1  and showing the opposite side of the replenishment system; 
           [0015]      FIG. 3  is a perspective, three-quarter sectional view taken in the direction of the arrows  3 - 3  of  FIG. 1 ; 
           [0016]      FIG. 4  is an exploded perspective view showing several major components of the subject system: plenum, air permeable cone and powder chamber displayed in a separated relationship, and 
           [0017]      FIG. 5  is a greatly enlarged detailed view of the foraminous fluidizing cone showing the air passing apertures therein. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0018]    The seasoning replenishment system  10  of the present invention is shown clearly in  FIGS. 1-3  and comprises a canister body  11  carried by wheels  12  that enable its portability along a processing deck in a food processing plant. A handle  13  is mounted at an upper portion of the canister body  11  and a flexible, seasoning discharge conduit  14  is arranged in communication with the interior of the canister body in a manner to be more fully described below. A vertically adjustable support peg  16  is mounted on the body in a position spaced from the common axis of the wheels  11  so, acting together, the peg  16  and wheels  12  establish a stable platform for receipt and discharge of powder-like seasonings from the canister  11 . A hermetically sealable product loading hatch or door  17  is arranged in the top of the canister body  11  providing for loading of food seasonings  20  into a powder chamber  15 , as shown in  FIG. 3 . 
         [0019]    A compressed air supply source  18  may be mounted integrally with the canister body  11 , as shown in  FIG. 1 , and may comprise well known components such as an electric motor driven air compressor and an associated compressed air storage tank, pressure regulator valve, gauge and filter (not shown). An air supply conduit  19 , as shown in  FIGS. 1 and 3 , serves to supply air at a preselected pressure into an air plenum  21  disposed as shown in  FIG. 3  at a lower portion of the canister  11 . Where the processing plant has a readily accessible supply of compressed air, as is frequently the case, the supply conduit  19  may be coupled to such air supply with appropriate couplings and air control valves and pressure gages, all well understood in the field. Desirably air pressure in the unit  10  for ablating and fluidizing purposes (which is to be distinguished from pneumatic conveying where air pressure “blows” the powder through a pipe) can be in the range of about 0.5 psi to about 12 psi. However the vast majority of seasoning powders  20  ablate from the bulk powder towards a fluidize flow below 7 psi and quite well at 3 psi. The operating principle is that when fluidized powder has all the properties of a fluid including hydrostatic head. Fluidized seasoning powder will readily flow up to a height above the container depending only on the difference in head pressure and the density of the powder. The fundamental formula Ap=yh applies where Ap=change in head pressure, y=the specific weight of the “liquid” (powder), and h=the change in elevation. It is this relationship that allows the velocity in the conduit  14  to be very low if desired, say for very fragile seasonings, or quite high. Pneumatic conveying systems cannot obtain such ranges of low flow velocities. 
         [0020]    The air plenum  21  is shown in  FIG. 4  separately from the assembled arrangement of  FIG. 3  and includes a cylindrical sidewall  22  ending at the upper portion with an outwardly extending belt flange  23 . Secured to the sidewall  22  is a bottom plate  24  with a central opening  26  for receipt there through in an air tight manner the seasoning discharge conduit  14 . An air conduit fitting  27  is mounted in the sidewall  22  to receive compressed air from the air conduit  19 . 
         [0021]    Referring specifically to  FIGS. 3 ,  4  and  5 , a right cone  31  of foraminous construction is shown and is equipped with a circumferential flange  32  at its widest upper portion, the flange  32  being constructed to mate in an air tight manner with the belt flange  23  of the plenum  21 . At its lower portion the foraminous cone  31  is equipped with a coupling  33  that enables a connection with the seasoning discharge conduit  14  as indicated in  FIGS. 3 and 4   b . It will be understood that seasoning powder  20  loaded into the powder chamber  15  seasoning unit  10  will free fall and be supported by the cone  31 . To prevent the powder  20  from packing down, the cone  31  is equipped with a multiplicity of apertures  34  for receiving there through a flow of air from the air plenum  24  which serves to “liquidify” the powder by ablating the boundary layer of seasoning powder laying on the cone  31 , or in other words cause the layer of powder  20  to react much like a liquid, flow like a liquid including supporting a “hydrostatic head.” This quality enables the powder to flow through the conduit  14  for delivery to the selected seasoning station on the processing plant&#39;s operation deck (not shown). 
         [0022]    The apertures  34  are formed in the fluidizing cone  31  in a process that virtually eliminates burrs which could impede smooth downward flow of the seasoning powder. One process that was found satisfactory, although others may be available, is that of chemical etching causing a hole through the stainless steel cone  31 . A preferable aperture or diametric hole size is about 0.03 inches (0.76 mm) although holes in the range of about 0.01 inches (0.025 mm) to 0.05 inches (1.27 mm) are effective to help the boundary layer of powder (where the powder seeks to contact the walls of the cone  31 ) to collapse and to keep the powder fluidized for flow through the conduit  14 . 
         [0023]    The apertures or holes  34  may be arrayed in horizontal rings along the cone wall in a spaced apart relationship in a range of about 1.5 inches (38.1 mm) to about 3.5 inches (88.9 mm) between adjacent holes in the ring with the spacing gradually increasing with the increase in the diameter of the ring. However the holes  34  in the uppermost rings are preferably about 2 inches (50.8 mm) apart so as to encourage more air flow sufficient to squelch the tendency of the power to clump or adhere to the adjacent metal surfaces. 
         [0024]    The powder chamber  15  is provided with downward and outwardly tapering sidewalls as may be seen in  FIG. 3 . This feature serves to discourage the seasoning powder  20  from adhering to the sidewalls and will encourage the powder when fluidized or liquefied along the boundary layer to flow from the powder chamber out through the conduit  14  in a quasi liquid or fluidized manner. A circumferential flange  35  on the chamber  15  is configured to match with the flanges  21  and  32  for securing together in an air tight manner the components  15 ,  21  and  31  to negate the dispersal of dust into the operating environment of the unit  10 . It will be understood, as illustrated in  FIG. 3 , that just the seasoning powder  36  that comes in range of the fluidizing apertures or jets  34  (a boundary layer) in the cone  31  becomes fluidized through ablation and flows downwardly, as indicated by the arrows  37 , while the large bulk of powder in the powder chamber  15  is not fluidized. Furthermore air flowing through the jets or apertures  34  penetrates or migrates through the powder bulk and pressurizes the powder chamber  15  furnishing a pressure head to the fluidized powder for delivery through the discharge conduit  14 . 
         [0025]    In operation of the seasoning apparatus  10  it is to first initially charge the powder chamber  15  with a selected food seasoning  20  via the hermetically sealable hatch  17 . A bag or sack of food seasonings may weigh from 35 to 50 lbs. (15.8 to 22.7 kg) and the capacity of the powder chamber  15  is ample to receive such quantity of seasonings or more. Commonly, when a bag of seasoning is poured into the powder chamber the powder mixture is segregated by various segregation mechanisms but when processed through the apparatus  10  the segregated quality is minimized and a substantially uniform seasoning out flow results. The seasonings discharge conduit  14  may terminate in a control or shut-off nozzle (not shown) so that seasoning flow may be stopped, kinking the conduit over a 180 degree bend can have the same effect of halting the initial seasoning flow or the discharge end may be simply elevated above the hydrostatic head. Pressurized air is delivered into the air plenum  21  via the conduit  19  from a suitable air supply  18  or the like thus charging the plenum  21  with air pressure in the desirable range of about 3 psi thus to liquefy or fluidize a quantum of the seasoning powder in the boundary layer along the upper surface of the cone  31  via air migration through the apertures  34  in the cone. An air pressure head is established in the powder chamber  15  above the pile or bulk of seasonings. The fluidized seasoning will thereby flow through the discharge conduit  14  to the delivery point at a food processing station for replenishing the seasonings carried away by the food products being processed. In the processing plant the seasoning replenishment apparatus  10  is parked next to the hopper contained on a seasoning applicator (not shown). By means of an automatic sensing system in the hopper the level of seasoning in the hopper and applicator  10 , the hopper is kept full until the apparatus&#39; 10 capacity is depleted of seasoning. At this point the apparatus  10  may be removed for refilling and then returned and reconnected to the hopper while the seasoning equipment continues operation. The ready portability of the unit  10  enabled by the wheels  12 , handle  13  and stability peg  16  is a large advantage for servicing several processing stations in the processing plant, rather than to have plant personnel lugging sacks of seasonings from station to station for dumping and thus raising clouds of dust in such operation. The seasoning apparatus  10  provides for essentially dust free delivery of food seasonings in the replenishing mode and effects an economy in the use of all of the seasonings with none resulting in objectionable dust in the processing plant during the replenishment operation. 
         [0026]    Presently there is a high awareness of food and seasoning allergies. It is essential to thoroughly clean a food processing system of any trace of the previous seasoning before the next batch with a different seasoning is run. The seasoning replenishment apparatus  10  is simple and easy to dean and with its portability can be removed from the processing area and replaced with another apparatus  10  loaded with another variety of seasoning. 
         [0027]    Generally food seasoning are highly hydroscopic and are supplied in plastic lined bags. When a run of a particular seasoning is completed and there is seasoning remaining in another type of conveying system this must be discarded because of its attractiveness for moisture in the air. The replenishment apparatus  10  as described herein acts as an air tight, sanitary storage container for the seasoning powder remaining at the end of the last processing run. The savings here can be considerable. 
         [0028]    While we have shown and described above what is considered to be a preferred embodiment of our invention in a portable, compact, food seasoning replenishment system and the process related thereto, we do not limit ourselves to the exact details of the construction set forth or to the air pressures and aperture sizes and orientation disclosed, and our invention embraces such changes, modifications and equivalents of the parts and their formation and arrangement as coming within the purview of the terms of the claims which follow below.

Technology Category: 1