Abstract:
An apparatus for cleaning foreign matter from separated tufts of fiber uses a revolving open reel type structure mounted within a porous housing to separate a conveying air stream from tufts of fiber conveyed thereby and deliver the tufts to a toothed cleaning cylinder which passes beneath a plurality of cleaning bars. The open reel utilizes brush like outer surfaces to sweep tufts of fiber from the housing back into the air stream adjacent the cleaning cylinder.

Description:
[0001]    This application claims priority to U.S. provisional application No. 60/950,222, filed Jul. 17, 2007, which is incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    This invention relates to cotton fiber processing and more particularly to an apparatus and method of separating foreign matter from fibrous cotton that has been ginned from the seed. 
         [0003]    Prior methods and apparatus include those such as illustrated in U.S. Pat. No. 6,088,881, incorporated herein by reference, wherein a revolving perforated drum is used to allow air flow through the drum such that a cleaning cylinder may remove cotton fiber from the perforated drum and carry it past a plurality of cleaning grid bars, thereby separating the air flow and removing foreign matter from the fibers, before the fiber is doffed from the cleaning cylinder for subsequent air flow to downstream processing. 
         [0004]    However, the perforated revolving cylinder of the &#39;881 apparatus, revolving at velocities to prevent agglomeration of the tufts in the air stream, develops centrifugal forces that cause the fine trash and very short fibers that penetrate the perforations to accumulate on the interior surfaces of the perforated cylinder. These accumulations require the use of compressed air blasts to cause them to move axially out the open ends of the cylinder. While the compressed air blasts provide a solution to this problem of accumulations, the maintenance and cost of the compressed air system detracts from the otherwise excellent performance of the apparatus per the &#39;881 patent. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0005]    An apparatus embodying features of the invention is depicted in the accompanying drawing wherein: 
           [0006]      FIG. 1  is a sectional side elevational view of an embodiment of an apparatus of the present invention. 
       
    
    
     BRIEF SUMMARY OF THE INVENTION 
       [0007]    It is an object of the present invention to provide an improved method and apparatus for separating foreign matter from tufts of fibrous cotton. A further object of the invention is to eliminate the need for a compressed air system for cleaning a perforated separator cylinder, while maintaining the other features of the &#39;881 patent by the use of a novel revolving separator in combination with a stationary arcuate perforated section. 
       DETAILED DESCRIPTION OF THE INVENTION  
       [0008]    An improved apparatus and method according to the present invention is illustrated in reference to  FIG. 1 , wherein fiber tufts comingled with foreign matter are pneumatically carried by a conveying air stream C into the apparatus via an air duct  11  as is well known in the art. Air duct  11  terminates adjacent an outer surface of a revolving cleaning cylinder  12  and a stationary separator housing. Duct  11  has an arcuate terminal wall portion  14  disposed adjacent to cleaning cylinder  12  to deliver the fiber tufts directly to a plurality of teeth  13  carried by the cleaning cylinder  12  and capable of holding the fiber tufts on said teeth  13 . The cylindrical housing comprises an arcuate non-porous surface  15 , a semi-cylindrical perforated surface or section  16 , and a non porous segment  15   a  spaced from terminal portion  14  of duct  11  at the end of a minor chord drawn through revolving cylinder  12 , such that the cylindrical housing is open to duct  11  opposite terminal wall portion  14 . Perforated surface  16  is a stationary separator that is porous to air flow there through but impervious to desirable fiber flow there through. Rotating within the cylindrical housing is an revolving air separator  17  which is pervious to both fiber and foreign matter. As may be seen in  FIG. 1 , terminal wall portion  14  of duct  11  converges toward revolving air separator  17  near cleaning cylinder  12  such that fiber tufts carried by the conveying air stream are directed substantially on to the teeth  13  of cleaning cylinder  12  while the direction of the conveying air flow is gradually changed toward the cylindrical housing comprising perforated surface  16 . 
         [0009]    Again as may be seen in  FIG. 1 , revolving separator  17  includes a plurality of circumferentially spaced outer surfaces  18  such that the spaces between spaced outer surfaces  18  are sufficient to allow the conveying air to pass between the spaced surfaces  18  as air duct  11  converges toward the spaced surfaces  18  without abruptly increasing the conveying air velocity. Outer surfaces  18  pass proximal to the revolving cleaning cylinder  12  and semi-cylindrical stationary surface  16   
         [0010]    In one embodiment outer surfaces  18  are defined by circumferentially spaced apart flexible belt-like strips running generally parallel to the axis of rotation of air separator  17  and generally radial to the axis of rotation. The strips are flexible radially and may be made of soft material to resist damage to the cleaning cylinder  12  or semi-cylindrical stationary surface  16 . In another embodiment, spaced outer surfaces  18  are defined by circumferentially spaced apart brush strips running generally parallel to the axis of rotation with the bristles facing outward generally radial to the axis of rotation of the air separator  17 . Suitable hub plates  22  hold the hubs  25  of the strips  18  in place forming an open reel. In either embodiment, the strips are preferably set at a deflection angle of the strips approximately 15 degrees backward from radial to the axis of rotation of the rotating separator  17  relative to its direction of rotation. 
         [0011]    The conveying air stream C thus passes through the air separator  17  and is exhausted from the cylindrical housing via perforated surface  16  to become exhaust air stream E. It is worthwhile to note that as outer surfaces  18  rotate across perforated surface  16  the surfaces  18  substantially sweep away any accumulations of matter on the stationary separator surface  16  and return any desirable fiber back to the conveying air stream C, proximal to terminal portion  14  of duct  11 . To effectively accomplish this, revolving outer surfaces  18  move at velocities that develop centrifugal forces sufficient to cause heavier than air matter revolving with the outer surface  18  to move substantially radially outwardly. Further the hubs or inner surface  25  of the strips  18  are configured to resist accumulation of matter heavier than air thereon, such that the rotation of the hub  25  and surfaces  18  moves such matter outwardly where it may be directed towards cleaning cylinder  12 . The rotation of revolving outer surfaces  18  is such that the commingled fiber and foreign matter are exposed to the teeth  13  of the cleaning cylinder  12  while the revolving outer surfaces  18  are rotating toward stationary semi cylindrical surface  16 . 
         [0012]    As will be understood from the prior art, the rotation of cleaning cylinder  12  carries the tufts past a stripping bar  27  and plurality of cleaning grid bars  23  disposed to separate a major portion of foreign matter from the cleaning cylinder  12 , which foreign matter may be disposed via a trash conveyor system for subsequent collection and baling. In the embodiment depicted, foreign matter is disposed via a waste airflow W. 
         [0013]    As will also appreciated, a rotating doffing cylinder or brush  24  removes the cleaned tufts from the teeth  13  of cleaning cylinder  12  and delivers the cleaned fibers to duct  26 . In the embodiment depicted, the cleaned tufts may be entrained in a doffing air flow D which passes adjacent doffing brush  24  and into duct  26 . 
         [0014]    The apparatus may be used to process cotton fiber according to the following description. Spaced apart individual tufts of fiber are conveyed in a high speed conveying air stream C to minimize agglomeration of the tufts, first exposing the air stream to revolving separator  17  which is porous to radially inward and outward air flow and revolving at speeds developing centrifugal forces that cause the fiber tufts and foreign matter rotationally moving with the porous revolving separator  17  to resist radially inward movement such that the fiber tufts and foreign are substantially removed from the conveying air C as it passes through the porous revolving air separator  17 . Thus, the preponderance of the fiber tufts and foreign matter are delivered directly to revolving toothed cleaning cylinder  12  in close proximity to the revolving separator  17 . 
         [0015]    A stationary generally cylindrical surface is located downstream of the revolving toothed cylinder  12  relative to the rotation of and proximal to the porous revolving air separator  17 . The stationary arcuate surface includes a porous section  16  being porous to air flow there through, but impervious to desirable fiber flow, and preferably contains one or more non-porous sections  15 . The rotational movement of the outer surfaces  18  carried by revolving porous air separator  17  proximate stationary arcuate surface sweeps any accumulations of desirable fiber from the upstream side of arcuate stationary surface  15 ,  16  delivering the fibers back into the conveying air stream C. The periphery of the revolving separator  17  should be porous to radially inward and outward air flow and have means on the radially inward surfaces to prevent the accumulation of matter heavier than air. 
         [0016]    Revolving toothed cylinder  12  holds the tufts while revolving past stripping bar  27  and cleaning bars  23  that strip foreign matter from the fiber tufts. A doffing brush or roller  24  revolving proximate and counter to toothed cleaning cylinder  12  removes the cleaned fibers from teeth  13  and delivers the cleaned fiber tufts from the process. 
         [0017]    While the forgoing specification describes only a few embodiments of the present invention, the invention is not so limited and is intended to encompass the full scope of the claims appended hereto.