US3173861A

US3173861A - Feeding mechanism for cigarette-making machine

Info

Publication number: US3173861A
Application number: US37939A
Authority: US
Inventors: Virgil D Hager; Lucien N Jones
Original assignee: American Tobacco Co
Current assignee: Brown and Williamson Holdings Inc
Priority date: 1960-06-22
Filing date: 1960-06-22
Publication date: 1965-03-16
Anticipated expiration: 1982-03-16

Description

March 16, 1.965 -v. D. HAGER ETAL' FEEDING MECHANISM FOR CIGARETTE-MAKING MACHINE Filed June 22, 1960 mvENToRs Virgil D. Hoger Lucien N. Jones` ATTORNE S United States Patent O M 3,173,861 FEEDEIG MECHANSM FOR SESARETTE- MAKING MACHENE.

Virgil D. Hager, Irvington-on-Hudson, NX., and Lucien N. Jones, Richmond, Va., assignors to The American Tobacco Company, New York, NSY., a corporation of New Jersey Filed .lune 22, 196), Ser. No. 37,939 6 Claims. (Cl. 299-137) This invention relates generally to tobacco feeds for continuous rod cigarette machines, and more especially to pneumatic winnowers for machines of this type.

The mechanism according to the invention is not only more simple than heretofore, but includes certain adjustable and other elements so related as to provide greatly improved pneumatic winnowing, better dust separation, and improved economy of operation.

To assure that only select tobacco leaf portions will be used in the manufacture of the cigarette rod, the tobacco must irst undergo a process of progressive refinement or selection. Accordingly, and as a customary preliminary step, previously cured tobacco is shredded, and some, but not all, of the stems, midribs and other foreign material removed. A mass of this shredded tobacco is then supplied to a tobacco feed machine which is adapted to refine or further select the desired shredded leaf tobacco from the mass of tobacco. The partially refined tobacco is fed to a bin in which a moving belt carries the tobacco toward a feed drum rotatable in the bin. Upon the outer periphery of the feed drum a plurality of carding pins are mounted so that as the feed drum rotates within the bin, it picks up a layer of tobacco. Mounted for counter-rotation re.ative to the feed drum and adjacent thereto is a refuser drum, the two drums forming a nip through which the tobacco is passed. Immediately adjacent the output of the two drums is a picker feed drum roll which picks a predetermined quantity of shredded tobacco from the feed drum` In the past it has been conventional to provide a mechanical winnowing device which receives tobacco from the picker feed drum roll and winnows the shredded tobacco by throwing it in different trajectories, depending on the different weights of the individual particles, in order to separate the select leaf portions from heavier particles such as stems. The denser tobacco stems, midribs and similiar relatively1 heavy particles will be thrown further by the winnower than the lighter leaf fragments from which the stem particles are to be separated. Accordingly, a trap and collector may be placed in the path of the heavier foreign particles while the lighter particles including selected leaf, fall into the rod former in the cigarette making machine. This method is not sufficiently selective as to particle weights, and it does not remove dust satisfactorily.

Various suggestions have been made to provide a more eliicient means for removing stems, midribs and other foreign material from the shredded mass of tobacco. Thus, it has been proposed, as in winnowing grain, to expose the shredded tobacco to a current of air which will carry the select tobacco leaf in one trajectory while permitting the heavier undesirable stem and midrib portions to follow another trajectory. The terms select tobacco and select leaf portions employed herein refer to those portions of the cured, shredded tobacco leaf from which high quality cigarettes can be made as distinguished from the denser stems `and mid-rib portions of the leaf and from less dense dust and very small particles of tobacco which lower the quality of cigarettes when present therein.

In accordance with the present invention, shredded to- 3,173,86l Patented Mar. 16, 1965 ICC bacco in proper quantities is permitted to fall under coutrolled conditions through a duct into a winnowing chamber. A current of air is blown through the chamber generally perpendicular to the path of the falling tobacco, and the velocity of the air current is so regulated relative to the velocity and density of the falling tobacco, that only the lighter materials therefrom, including select tobacco leaf portions, will be carried by the air stream from the chamber. The latter are then deposited by the air current upon a moving belt for later manufacture into a continuous cigarette rod. While these select portions fall toward the belt, the very small particles and dust Iare lseparated therefrom by the same air current. The heavier tobacco stems and midribs, unable to be supported by the air current, fall through an opening providing a trap in the bottom of the winnowing chamber.

As a further aspect of the invention, shredded tobacco from a picker roll is dropped into a feed duct located above the winnowing chamber which is provided with a series of inclined baffles to inhibit the fall o-f the tobacco and thus control its velocity of descent.

The inclined baffles are preferably adjustable so that they may be set at the pnoper angle of inclination to assure that the falling stream of tobacco will be fed into the winnowing chamber at the proper rate. Additionally, the battles serve the useful purpose of distributing the shredded tobacco from the picker into a fairly flat, loose web of uniform thickness for ethcient pneumatic winnowing thereof.

A further feature of the apparatus herein described is that the line tobacco and dust are blown with the desired select leaf portions into a separation chamber adjacent to the Winnowing chamber. The select leaf portions of the tobacco are here deposited upon a conveyor clt but the dust is carnied bythe same air stream through an exhaust outlet in the separation chamber, The dust particles are subsequently removed from the air stream by a filter or dust separator located in the return air 'duct from the separation chamber.

These and other aspects of the invention will be better understood upon consideration of the following detailed description together with the accompanying drawing of a pneumatic winnower mechanism constructed according to the invention, and which is adapted to feed a cigarette making machine.

The drawing comprises a schematic central vertical section of the machine in accordance with the invention.

With reference to the drawing, the feeding mechanism for a cigarette making machine is shown to comprise a base structure 8 having a vertical extension 9 on which is mounted an outer casing l@ which is cornpartmented to form a hopper or bin 11 adapted to receive a quantity of prepared tobacco leaf l2. The tobacco leaf l2 constitutes a homogeneous mass and although, preferably, some of the stem and other foreign material should have previously been removed from the tobacco, leaving a large portion of usable tobacco leaf in a generally shredded condition, much of the stems, midribs and foreign material remain. These have been indicated generally by the darker or heavier lines throughout the tobacco l2.

A feed drum 13 is mounted for rotation in the direction of the arrow at one side of the bin and is provided with a large number of peripherally mounted carding pins lll which catch the tobacco and carry a layer thereof around with the drum 13. Adjacent the feed drum 13 is a refuser drum l5 which is mounted for relative counter-rotation thereto (as shown by the arrow therein) and which is also provided with a plurality of carding pins 16. A

j conveyor belt 17 which forms the bottom of the bin il urges the tobacco 12 toward the drums i3, 15. These two drums form a nip through which passes a thin layer or web of shredded tobacco. A picker feed drum roll 1b is mounted for rotation with and adjacent to the feed drum 13 and is adaptedto remove a predetermined quantity of shredded tobacco from the surface of the feed drum i3.

The shredded tobacco removed from drum 13 falls into a feed, duct 19. Two adjustably inclined baffles or plates 20, 2l, staggered one above the other at the lower portion of the duct 19, are adapted successively to intercept the falling tobacco leaf. By experimentally adjusting the angle (with respect to the vertical) at which each of the bales 2i), 21 is set, the velocity of the falling tobacco may be predetermined within. desired limits. If the baffles are of sheet metal they may be adjusted by bending; otherwise by moving them on friction hinges on which they maye be supported, or by other Well-known means. The shredded tobacco leaf, including stems and foreign material, flows from the baiie 21 into a passage 22, the lower wall 23 of which serves as a third baille for controlling the velocity of the falling tobacco. The lower portion 45 of wall 23 extends into pneumatic duct 24 far enough to form a constriction or port 25 through which air flows at high velocity. This wall portion 45 is perforated to permit some of the air to blow through the shredded tobacco as it descends toward the port 25. As a result, the mass of tobacco is loosened and the smaller tobacco particles begin to separate from the larger particles before reaching the port 25. This assures more complete separation of the select tobacco from the heavier parts in the winnowing chamber below referred to.

The operation of the apparatus above described is such that a predetermined quantity of shredded tobacco leaf, including some undesirable particles such as stem or other foreign material, will be fed from the feed duct 19 into a winnowing chamber 26 located immediately below the feed passage 22 at a rate controlled by the angle of inclination of the adjustable baffles 2) and 2l.

Leading into the chamber 26 from the right, as viewed in the drawing, is the mentioned pneumatic duct 24 which is supplied with moving air at a velocity adjustable by a vane 27. The column of moving air in the duct passes through the winnowing chamber 26 in a direction generally transverse to the gravitational path which the tobacco leaf follows when spilled from the feed passage 22. The velocities of the falling tobacco and of the moving air column are regulated so that the heavy tobacco stem particles will be relatively unaffected by the air current and, passing through it, will fall through a discharge opening or trap 28 in the bottom of chamber 26. The lighter particles including select shredded tobacco leaf thus separated from the heavier particles, are blown at an angle slightly above the horizontal, through an exit nozzle 29 from the chamber 26, into the adjacent separation chamber 30. A fallout of select shredded tobacco leaf will consequently be deposited in a continuously forming layer upon the moving belt 31, which travels at a slightly greater upward angle than the jet from the exist nozzle. The tobacco so selected is carried by the belt 31 through a select-tobacco exit formed between the end of the belt traverse and feeder roll couple 32, 33 to a picker roll 34 and thence to the feed chute 35.V This chute feeds the tobacco to the rod former of the cigarette making machine, as indicated in the drawing.

The chamber 30 is provided with seals 36, 37, 38 which` permit a pressure differential to exist therein relative to the exterior of the casing 10. Accordingly, substantially all of the air blown into the chamber 30 will be exhausted through an exhaust opening 39 in the wall of the casing situated in the upper lefthand corner of chamber 3G, as illustrated. Thus, light finely divided foreign materials such as tobacco dust and similar undesired material will be carried by the air leaving the chamber 3) through the exhaust opening 39. The pneumatic winnower of the present invention therefore not only separates the heavier particles from the select shredded leaf tobacco, but also separates fine dustlike materials therefrom.

As shown in the phantom lines, the exhaust opening 39 leads to an exhaust-blower 4@ which withdraws air from chamber 30 and blows it through a connecting duct 4l into dust filter-collectors 42, d3. Filters of the cyclone separator type have proved to be especially satisfactory. The cleaned air from the filter-collectors passes through return duct 44 and air-velocity adjuster 2,7 into pneumatic duct 24 to be recirculated. The air adjusting device 27 may be of any suitable form and may be located in any other preferred position in the air-circulating system.

lt will be understood that various departures from the specific structure shown and described above may be made by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, the invention is limited only by the appended claims.

We claim:

1. Tobacco feeding and selecting mechanism including a pneumatic winnower comprising atwinnowing chamber, tobacco feed control4 means for controlling the descent of a stream of shredded tobacco into said chamber, said shredded tobacco including select leaf portions, heavier portions and lighter dust-like portions, said feed control means including a series of relatively inclined baies over which the tobacco descends in succession, a pneumatic duct for conducting a stream of air in a direction substantially only transverse to the descending stream of tobacco, at least a portion of the lowest one of saidV baiiles extending into said duct and having perforations through which part of said air stream blows into the descending tobacco to loosen the same and to separate at least some of said lighter portions therefrom, said duct having a lower wall and said last-mentioned baille portion being spaced from said lower wall to form therebetween a port which directs the. remainder of said air stream in a jet across the winnowing chamber, means for maintaining the velocity of said jet such as to carry with it substantially only portions of shredded tobacco which are lighter than said heavier portions, and means for receiving said heavier portions.

2. Tobacco feeding and selecting mechanism including a pneumatic winnower comprising a winnowing chamber having a tobacco-receiving opening at the top, a tobacco feed duct emptying into saidtop opening, a series of downwardly and relatively inclined baflles arranged in said feed duct between the top and bottom thereof over which the tobacco descends so as to impede the normal gravitational descent of tobacco toward the chamber, one of said baffles extending downwardly to form a Wall of said chamber, said Wall having a plurality of perforations adapted to form a large number of small air jets into the mass of descending tobacco, and a port below said perforated wall shaped to direct a larger single jet of air across said chamber and thus substantially transverse to the stream of tobacco falling across it, the angle of inclination of at least one of saidl baffles being adjustable to control the rate of descent of tobacco in said duct.

3. Tobacco feeding and selecting mechanism including a pneumatic winnower comprising a winnowing chamber having a top tobacco-receiving opening and a bottom heavy particle discharge opening, a generally vertically disposed tobacco feed duct having atop inlet opening and a bottom discharge opening emptying into the top opening of said winnowing chamber and to a series of downwardly and oppositely inclined baffles arranged in said feed duct between the top and bottom openings thereof so as to impede the gravitational descent of the Vfeed tobacco toward the discharge opening of said feed duct, said winnowing chamber having a port at one side thereof below said bailles and means for maintaining a stream of air through said port, said port being disposed to direct said stream of air substantially only perpendicularly to the stream of tobacco as the tobacco falls across said air stream, and a nozzle at the side of said chamber opposite said port having a discharge end and an intake end into which said air stream is directed, said air stream having a velocity suicient to carry select shredded leaf tobacco and particles finer than said select tobacco into said nozzle but insucient to carry particles heavier than said select tobacco, whereby said heavier particles fali to the bottom of said winnowing chamber and into the bottom heavy particle discharge opening thereof, and a separation chamber into which said nozzle discharges, said separation chamber including means for separating tine particles from select tobacco.

4. Tobacco feeding and selecting mechanism according to claim 3, in which said means for maintaining a stream of air comprises pneumatic duct means and a blower and dust separating means included therein, said winnowing chamber comprises an extension of said pneumatic duct, said chamber port is at least partly defined by one of said bafiies and a wall of said pneumatic duct, and said nozzle mearis providing a constricted outlet of said winnowing chamber.

5. Tobacco feeding and selecting mechanism according to claim 4 in which said blower, said pneumatic duct means and both of said chambers are interconnected in a closed pneumatic system, so that said air jet is maintained by recirculated air, said separation chamber, said nozzle and said air stream being so proportioned and relatively disposed that particles iiner than the select tobacco are maintained agitated in the separation chamber and thus are removed therefrom by the action of said blower.

6. Tobacco feeding and selecting mechanism according to claim 3 in which said separation chamber is iarger than said winnowing chamber, said means for separating includes a moving belt in said separation chamber upon which said select shredded leaf portions of tobacco fall from said nozzle, means for receiving said select tobacco from said belt, an air outlet in said separation chamber, and air conducting means including a blower and dust separating means connecting said air outlet to said means for maintaining a jet of air in said winnowing chamber so as to maintain the air jet principally with re-circulated air.

References Cited in the le of this patent UNITED STATES PATENTS 147,797 Schwab Feb. 24, 1874 973,698 Pugibet Oct. 25, 1910 1,755,080 Schunemann Apr. 15, 1930 1,903,931 Molins et al Apr. 18, 1933 2,267,326 Eissmann Dec. 23, 1941 2,634,171 Williams Apr. 7, 1953 2,727,518 Carder Dec. 20, 1955 3,026,878 Essmann Mar. 27, 1962 3,030,965 Labbe Apr. 24, 1962 FOREIGN PATENTS 109,728 Austria May 25, 1928 626,782 Germany Mar. 2, 1936 819,014 Germany Oct. 29, 1951

Claims

1. TOBACCO FEEDING AND SELECTING MECHANISM INCLUDING A PNEUMATIC WINNOWER COMPRISING A WINNOWING CHAMBER, TOBACCO FEED CONTROL MEANS FOR CONTROLLING THE DESCENT OF A STREAM OF SHREDDED TOBACCO INTO SAID CHAMBER, SAID SHREDDED TOBACCO INCLUDING SELECT LEAF PORTIONS, HEAVIER PORTIONS AND LIGHTER DUST-LIKE PORTIONS, SAID FEED CONTROL MEANS INCLUDING A SERIES OF RELATIVELY INCLINED BAFFLES OVER WHICH THE TOBACCO DESCENDS IN SUCCESSION, A PNEUMATIC DUCT FOR CONDUCTING A STREAM OF AIR IN A DIRECTION SUBSTANTIALLY ONLY TRANSVERSE TO THE DESCENDING STREAM OF TOBACCO, AT LEAST A PORTION OF THE LOWEST ONE OF SAID BAFFLES EXTENDING INTO SAID DUCT AND HAVING PEROFRATIONS THROUGH WHICH PART OF SAID AIR STREAM BLOWS INTO THE DESCENDING TOBACCO TO LOOSEN THE SAME AND TO SEPARATE AT LEAST SOME OF SAID LIGHTER PORTIONS THEREFROM, SAID DUCT HAVING A LOWER WALL AND SAID LAST-MENTIONED BAFFLE PORTION BEING SPACED FROM SAID LOWER WALL TO FORM THEREBETWEEN A PORT WHICH DIRECTS THE REMAINDER OF SAID AIR STREAM IN A JET ACROSS THE WINNOWING CHAMBER, MEANS FOR MAINTAINING THE VELOCITY OF SAID JET SUCH AS TO CARRY WITH IT SUBSTANTIALLY ONLY PORTIONS OF SHREDDED TOBACCO WHICH ARE LIGHTER THAN SAID HEAVIER PORTIONS, AND MEANS FOR RECEIVING SAID HEAVIER PORTION.