Infeed Device for Dedusting Apparatus

Abstract

An infeed device provides a configuration that improves the flow of particulate material into a double wash deck dedusting apparatus. The infeed device is formed with a circular inlet opening, an oval-shaped discharge opening and step sides interconnecting the inlet and discharge openings to prevent bridging in particulate material being fed through the infeed device onto the wash decks. The infeed device can be formed as a separate member that can be inserted into the infeed opening of existing dedusters. The oval-shaped discharge opening is substantially smaller transversely than the diameter of the inlet opening, but has a longitudinal length that is equal to the diameter of the inlet opening and equal to the longitudinal length of the wash decks. The joinder of the wash decks is blunted to eliminate a divider edge on which plastic streamers can hang up while being fed to the wash decks.

1 . A dedusting apparatus for removing dust particles from particulate product material, comprising:
 a casing having a back panel, a front panel and an interior panel dividing the casing into a main housing and an air plenum behind the main housing, said air plenum being divided by a separator panel into a clean air plenum and a dusty air plenum;   a wash deck apparatus supported in the main housing and including:
 a pair of first wash decks mounted to be inclined downwardly and outwardly in opposing lateral directions from a central axis; 
 a pair of lower deck members connected respectively to said first wash decks and oriented downwardly and inwardly toward said central axis to form a generally diamond-shaped configuration; 
 a pair of second wash decks oriented generally parallel to said lower deck members and being positioned respectively below said first wash decks to receive a flow of product material discharged from said first wash decks, each of said first and second wash decks having a plurality of holes and slots therein for the passage of air therethrough as product flow on top of the respective wash deck; and 
 a Venturi zone located at the end of each said first wash deck and bounded on each respective outboard side by a deflector plate; 
   a product inlet port connected in flow communication to said main housing at said central axis to introduce an inflow of particulate material to be cleaned to said first wash decks, said product inlet port directing the inflow of particulate material into a discharge opening having linear longitudinally extending sides to direct the inflow of particulate material across a corresponding longitudinal dimension of said pair of first wash decks;   a product discharge port connected in flow communication to said main housing at said central axis between said second wash decks to receive particulate material from said second wash decks for discharge from said main housing;   a clean air inlet port connected in flow communication to said clean air plenum for the introduction of air under pressure into said clean air plenum so as to pass upwardly through said pair of first wash decks and said pair of second wash decks.   
   
   
       2 . The dedusting apparatus of  claim 1  further comprising a magnetic flux field generator mounted on said product inlet port to create a magnetic flux field to disrupt any static charges attracting the dust particles to the product particles. 
   
   
       3 . The dedusting apparatus of  claim 1  wherein said clean air plenum includes:
 a first air inlet opening in said interior panel below said first wash decks and above said lower deck members to introduce a flow of air through said holes and slots in said first wash decks;   a pair of second air inlet openings in said interior panel below said second wash decks to introduce a flow of air through said holes and slots in said second wash decks; and   a Venturi flow chamber extending from below each said second wash deck and projecting rearwardly through said interior panel and terminating above the respective said second wash deck behind the corresponding said deflector plate to deliver a flow of air behind said deflector plates to enhance air flow in said respective said Venturi zone.   
   
   
       4 . The dedusting apparatus of  claim 1  wherein said product inlet port is formed with a generally circular inlet opening having a diameter dimension and an oval-shaped discharge opening including said linear sides spaced below said inlet opening, said discharge opening being centered over said pair of first wash decks. 
   
   
       5 . The dedusting apparatus of  claim 4  wherein said discharge opening is formed with rounded ends that define a longitudinal length dimension of said discharge opening, said longitudinal length dimension being substantially equal to said diameter dimension of said inlet opening. 
   
   
       6 . The dedusting apparatus of  claim 5  wherein said discharge opening has a transverse width dimension extending between said linear sides, said transverse width dimension being smaller than said diameter dimension of said inlet opening. 
   
   
       7 . The dedusting apparatus of  claim 6  wherein said product inlet port is formed with side walls extending between said inlet opening and said discharge opening to transition said circular inlet opening into said oval-shaped discharge opening, said discharge opening being spaced vertically from said inlet opening to establish steep side walls disposed at a vertical angle greater than sixty degrees. 
   
   
       8 . The dedusting apparatus of  claim 7  wherein said side walls have a vertical angle of about 75° at the center of the longitudinal sides and increasing to 90° at said rounded ends. 
   
   
       9 . The dedusting apparatus of  claim 6  wherein said pair of first wash decks are joined by a truncated portion that presents a generally horizontal surface beneath said discharge opening of said inlet device. 
   
   
       10 . The dedusting apparatus of  claim 9  wherein said truncated portion is positioned centrally with respect to said discharge opening and presents said generally horizontal surface with a transverse width dimension smaller than the corresponding transverse width dimension of said discharge opening. 
   
   
       11 . The dedusting apparatus of  claim 6  wherein said product inlet port is formed as a separate component that is removable from said main housing. 
   
   
       12 . An inlet device for a dedusting apparatus for removing dust and debris from particulate material, said dedusting apparatus including a pair of oppositely oriented wash decks positioned below an inlet port of said dedusting apparatus, comprising:
 a generally circular flange defining an inlet opening; and   side walls extending downwardly from said flange and defining an oval-shaped discharge opening centered over said wash decks and having generally linear longitudinally extending sides and rounded ends.   
   
   
       13 . The inlet device of  claim 12  wherein said inlet opening has a diameter dimension and said discharge opening has a longitudinal length dimension extending between said rounded ends, said longitudinal length dimension being substantially equal to said diameter dimension of said inlet opening. 
   
   
       14 . The inlet device of  claim 13  wherein said discharge opening has a transverse width dimension extending between said linear sides, said transverse width dimension being smaller than said diameter dimension of said inlet opening. 
   
   
       15 . The inlet device of  claim 14  wherein said side walls transition said circular inlet opening into said oval-shaped discharge opening, said discharge opening being spaced vertically from said inlet opening to establish steep side walls disposed at a vertical angle of about 75° at the center of the longitudinal sides and increasing to 90° at said rounded ends. 
   
   
       16 . The dedusting apparatus of  claim 14  wherein said wash decks are joined by a truncated portion that presents a generally horizontal surface beneath said discharge opening of said inlet device, said truncated portion being positioned centrally with respect to said discharge opening and presenting said generally horizontal surface with a transverse width dimension smaller than the corresponding transverse width dimension of said discharge opening. 
   
   
       17 . In a dedusting apparatus for removing dust and debris from particulate material, said dedusting apparatus including a pair of oppositely oriented wash decks positioned below an inlet port of said dedusting apparatus, the improvement comprising:
 an inlet device having a generally circular flange defining an inlet opening and side walls extending downwardly from said flange to define an oval-shaped discharge opening centered over said wash decks, said discharge opening having generally linear longitudinally extending sides and rounded ends.   
   
   
       18 . The dedusting apparatus of  claim 17  wherein said inlet opening has a diameter dimension, said discharge opening has a longitudinal length dimension extending between said rounded ends and a transverse width dimension extending between said linear sides, said longitudinal length dimension being substantially equal to said diameter dimension of said inlet opening, while said transverse width dimension is smaller than said diameter dimension of said inlet opening. 
   
   
       19 . The inlet device of  claim 18  wherein said side walls transition said circular inlet opening into said oval-shaped discharge opening, said discharge opening being spaced vertically from said inlet opening to establish steep side walls disposed at a vertical angle greater than 60° at the center of the longitudinal sides and increasing to 90° at said rounded ends. 
   
   
       20 . The dedusting apparatus of  claim 19  wherein said wash decks are joined by a truncated portion that presents a generally horizontal surface beneath said discharge opening of said inlet device, said truncated portion being positioned centrally with respect to said discharge opening and presenting said generally horizontal surface with a transverse width dimension smaller than the corresponding transverse width dimension of said discharge opening.