Apparatus and method for post-threshing inspection and sorting of tobacco lamina

A method for the post-threshing inspection and sorting of tobacco lamina, comprising:

• providing a substantially vertically oriented separation conduit defined by an internal sidewall and which has a proximal and a distal end, and an intermediate portion, and wherein the internal sidewall of the substantially vertically oriented separation conduit further defines an internal passageway extending between the proximal and distal ends;
• providing a substantially moveable wall within the internal passageway of the separation conduit, and wherein the moveable wall has opposite sides;
• delivering a source of a tobacco lamina, and other contaminants each having given weights, and which have been produced from a threshing operation, into the internal passageway at a location which is between the proximal and distal ends of the substantially vertically oriented separation conduit;
• delivering a first air stream having a given air pressure, volume, and speed into the proximal end of the vertically oriented separation conduit and which is sufficient to carry away tobacco lamina and other contaminants which weigh less than about 0.8 grams/cm2 and in the direction of the distal end of the substantially vertically oriented separation conduit;
• adjusting the position of the moveable wall within the separation conduit so as to adjust the speed of the first air stream, and wherein the first air stream does not pass through the moveable wall;
• delivering a second air stream having a given air pressure and volume into the internal passageway defined by the substantially vertically oriented separation conduit at a location near the intermediate portion thereof, and wherein the tobacco lamina and other contaminants being carried by the first air stream are moved away from internal sidewall of the substantially vertically oriented separation conduit;
• providing an inspection station located intermediate the proximal and distal ends of the substantially vertically oriented separation conduit and downstream relative to the second air stream, and which visually inspects and identifies defective tobacco lamina and other contaminants being carried by the air stream;
• providing a reject station which is located downstream of the inspection station and operably coupling the reject station with the inspection station;
• providing a suction device which is coupled in fluid flowing relation relative to the distal end of the separation conduit, and which, when energized, is effective in maintaining a speed of movement of the tobacco lamina and other contaminants passing into, and out of, the reject station, and in the direction of the distal end of the separation conduit;
• and
• removing defective tobacco lamina and other contaminants being carried by the air stream in the reject station.

An apparatus for post-threshing inspection and sorting of tobacco lamina, comprising:

• a separation conduit having a proximal end, a distal end, and an intermediate portion, and wherein the separation conduit further has an internal facing surface which defines an internal cavity which extends between the proximal and distal ends;
• a first source of pressurized air delivered to the proximal end of the separation conduit, and which produces an air stream which moves at a given speed from the proximal, to the distal end of the separation conduit;
• a selectively moveable wall having opposite surfaces, and which is mounted within the separation conduit and which further is located between the proximal and distal ends of the separation conduit, and which, when moved, adjusts the speed of the air stream traveling on one side of the moveable wall, and wherein the air stream does not pass through the moveable wall;
• a guide portion positioned downstream of the selectively moveable wall, and made integral with the intermediate portion, and which defines a portion of the internal cavity, and wherein a first and a second guide plate are individually mounted in the internal cavity of the guide portion, and further individually define respective spaces therebetween the respective guide plates, and the adjacent guide portion, and wherein the air stream generated by the first source of pressurized air passes between the respective guide plates, and not through the respective spaces defined by the first and second guide plates;
• an air injection port which is made integral with the guide portion, and which is fluid flowingly coupled with each of the spaces defined by the respective first and second guide plates;
• a second source of pressurized air delivered to the respective air injection ports, and which travels along the respective spaces defined by the respective guide plates, and into the portion of the internal cavity which is defined by the guide portion, and at a given speed which is equal to, or greater than, the speed of the air stream delivered by the first source of pressurized air;
• a conveyor for carrying a source of tobacco lamina, and other contaminants, to the separation conduit, and wherein the conveyor has an intake and a discharge end;
• an air lock positioned in downstream relation relative to the distal end of the conveyor, and which receives the tobacco lamina, and other contaminants, which are transported by the conveyor, and wherein the air lock deposits the source of tobacco lamina, and other contaminants into the internal cavity of the separation conduit at a location between the proximal and the distal ends thereof, and wherein the air stream generated by the first source of pressurized air carries the tobacco lamina, and other contaminants, in the direction of the distal end of the separation conduit, and between the guide plates which are mounted in the guide portion, and wherein the second source of pressurized air traveling along the guide portion causes the tobacco lamina, and other contaminants, being carried by the air stream generated by the first source of pressurized air to move away from internal facing surface of the separation conduit, and pass centrally through the guide portion;
• a delivery chute defining an internal passageway which is coupled in downstream receiving relation relative to the air lock, and which is further located in upstream delivering relationship relative to the separation conduit, and wherein the delivery chute has a first end coupled to the air lock, and a second end coupled to the separation conduit, and wherein the delivery chute is defined, in part, by a back sidewall, and a bottom sidewall which are spaced apart to form a gap;
• an air manifold which is operably coupled to a second air stream which enters the air manifold, and escapes through the air manifold, and wherein the second air stream escaping from the air manifold passes through the gap formed by the back and bottom sidewall of the delivery chute, and then further engages the source of tobacco lamina, and other contaminants, delivered by the air lock to the delivery chute so as to impede sedimentation of the tobacco lamina, and other contaminants, on the bottom sidewall of the delivery chute, and to further move the tobacco lamina, and other contaminants, into the separation conduit;
• an inspection station located downstream of the guide portion, and which optically inspects the air stream carrying the tobacco lamina, and any other contaminants, which have been substantially centralized by the guide portion, and which further identifies defective tobacco lamina, and any contaminants, which are passing through the inspection station, and which further generates an electrical signal;
• a reject station coupled in signal receiving relation relative to the inspection station, and downstream relative thereto, and which ejects the previously identified defective tobacco lamina, and any contaminants, from the air stream passing through the reject station, and wherein the reject station is maintained at substantially ambient pressure;
• a rejection container coupled in receiving relation relative to the rejection station, and which receives the unacceptable tobacco lamina and/or other contaminants which are removed from the rejection station by the action of the reject station, and wherein the rejection container is maintained at substantially ambient pressure;
• and
• a suction device mounted on the distal end of the separation conduit, and which provides a predetermined amount of suction pressure to the reject station in an amount which substantially maintains the flow of the tobacco lamina, and other contaminants, into the reject station, and the flow of acceptable tobacco lamina passing through the reject station, and to the distal end of the separation conduit, while simultaneously not withdrawing previously rejected tobacco lamina, and other contaminants, from the rejection container.