Classifying – separating – and assorting solids – Sorting special items – and certain methods and apparatus for... – Separating means
Reexamination Certificate
2000-03-09
2001-10-23
Walsh, Donald P. (Department: 3653)
Classifying, separating, and assorting solids
Sorting special items, and certain methods and apparatus for...
Separating means
C209S293000, C209S298000, C209S379000, C209S389000
Reexamination Certificate
active
06305552
ABSTRACT:
FIELD OF THE INVENTION
The present invention is generally related to an apparatus for removing matter from tobacco during tobacco processing and more particularly to a separator for separating tobacco stalks and foreign matter from tobacco stems.
BACKGROUND OF THE INVENTION
It is well known that some types of tobacco are harvested by removing individual ripe leaves from the stalk of a standing tobacco plant to allow the remaining leaves to remain in the field to continue to grow and that other types of tobacco are harvested by removing from the field the entire tobacco stalk with the tobacco leaves still attached. The stalk is the main trunk of the tobacco plant that supports the tobacco leaves, each of which is attached to the stalk by a stem. The stem is the mid-rib of the tobacco leaf.
When tobacco is harvested by removing the entire stalk from the field, the tobacco leaves are typically cured on the stalk. After curing, tobacco farmers strip the leaves from the stalk so that the leaves can be marketed. Pieces of stalk sometimes find their way into the tobacco sold by tobacco farmers because the farmers do not always break the leaves from the stalk cleanly when they strip them. In burley tobacco production, for example, where tobacco is cured on the stalk, careless removal of the cured leaves from the stalk can result in pieces of stalk in the product.
Stalks most often end up in the tobacco product when tobacco leaves are harvested individually using mechanical harvesters for curing in bulk curing barns. Thus, it can be appreciated that although the leaves are always removed from the stalk before marketing regardless of the harvesting or curing method used, stalks frequently end up mixed in with the leaves and must be removed in a subsequent processing step.
In the threshing and separating processes employed in a tobacco stemmery, the tobacco is usually mechanically threshed and then separated onto various components. The cut tobacco forms a mixture that includes leaf parts (lamina or strip), stems, stalk parts and soil particles. As the tobacco is processed, the useful tobacco components of the mixture are separated out and the unusable portion of the mixture is discarded. When leaf tobacco is processed for use in cigarettes, chewing-tobacco or cigars, the useable end-products are the leafy particles (sometimes referred to as the “strip”), the stems, and the small leaf particles (sometimes referred to as the “fines”). The undesirable end-products are soil particles, any other non-tobacco products and the stalks. This undesirable material must be removed from the tobacco during processing.
The leaf parts and leaf particles are relatively easy to separate from the rest of the cut tobacco by, for example, exposing the threshed tobacco mixture to a vertical moving air current. Any stalks present in the mixture usually remain in the mixture with the stems after the leaf fraction is removed. However, because the stalks and stems typically have the same density, the stems must be separated from the non-usable material in a separate subsequent processing step.
Tobacco stems are used in tobacco product manufacture in one of two ways. The larger stems (greater than one and one half inches) are conditioned, rolled, cut and expanded to produce a product similar in characteristics to cut leaf tobacco. The smaller stems are ground into a pulp and mixed with the tobacco fines, water and binders to form a slurry from which reconstituted tobacco is made. In both cases, it is very important that the stems are free of non-tobacco products and stalks.
The traditional means for removing the stalks from the stems is by manually inspecting the tobacco and passing the stems over a vibrating conveyor containing a screen comprised of longitudinal rods spaced about three eighths of an inch apart. Although this method works most of the time, the screen tends to choke with the longer stems and requires frequent attention. Therefore, there exists a need in the tobacco processing business for a simpler, more efficient and more economical way to remove the stalks from processed tobacco stems.
SUMMARY OF THE INVENTION
To meet the need expressed above, there is disclosed and described herein an apparatus for separating tobacco stem particles from a mixture containing such particles and tobacco stalk particles obtained in a threshing and separating process employed in a tobacco stemmery. The apparatus is comprised of a hollow drum or reel having a longitudinal axis, the hollow drum being mounted for rotational movement about its axis and the axis being disposed at a slight angle with respect to the horizontal so as to establish a higher inlet end and a lower outlet end of the hollow drum. A mixture handling structure is constructed and arranged with respect to the inlet end of the hollow drum to feed a supply of a mixture containing tobacco stem particles and tobacco stalk particles obtained in the threshing and separating process into the inlet end of the hollow drum. The hollow drum has a periphery formed of a foraminus structure that includes a plurality of generally axially extending parallel bars spaced apart a distance sufficient to allow the passage of tobacco stem particles therethrough while substantially preventing the passage of tobacco stalk particles therethrough. A power operated assembly rotates the hollow drum about its axis at a speed sufficient to cause a portion of the mixture entering the inlet end and falling on the lowermost bars which has not passed through the spaces between the bars to be carried through a cycle which includes an upward movement with the movement of the bars and a falling movement downwardly onto the lowermost bars at a position downstream and a repetition of the cycle until the remaining mixture is moved out of the lower outlet end of the hollow drum. A tobacco stem handling structure below the hollow drum receives the tobacco stem particles passing through the spaces between the bars as the particles of the mixture are cycled within the rotating hollow drum and moves the tobacco stem particles away. A tobacco stalk particle handling structure at the outlet end of the hollow drum receives the remaining mixture moved out of the lower outlet end of the hollow drum and moves the remaining mixture away.
The stalk removal apparatus cleans itself as the hollow drum tumbles the mixture but, if a stem or stalk becomes entrapped between the bars, a cleaning device in the form of a blockage clearing mechanism operates periodically to dislodge it. In this way, the stalk removal apparatus cleans itself continuously. The stalk or stem cleared from between the bars by the blockage clearing mechanism is returned to the reject product contained within the hollow drum. The blockage clearing mechanism is operatively associated with the upper exterior periphery of the hollow drum and is constructed and arranged to move particles lodged in the spaces between the bars downwardly during the rotational movement of the hollow drum. An additional advantage of the apparatus is that the tumbling action of the mixture on the dry stems dislodges any remaining attached leaf lamina. The dislodged leaf lamina is reclaimed as fines in a subsequent system designed for this purpose. Processing of the mixture in the apparatus produces clean, polished stems that are attractive to the customer.
Another objective of the invention is to provide a separator comprising a hollow drum having a longitudinal axis, the drum being mounted for rotational movement about its axis and the axis being disposed at a slight angle with respect to the horizontal so as to establish a higher inlet end and a lower outlet end of the drum. A feeding structure is constructed and arranged with respect to the inlet end of the hollow drum to feed thereto a supply of a mixture containing first and second size fractions. The hollow drum has a periphery formed of a foraminus structure including generally axially extending parallel bars that are spaced apart from one another a distance sufficient to allow the passage of the first si
Pillsbury & Winthrop LLP
Schlak Daniel K.
Universal Leaf Tobacco Company, Inc.
Walsh Donald P.
LandOfFree
Apparatus for removing matter from tobacco stems does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus for removing matter from tobacco stems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for removing matter from tobacco stems will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2558842