US3779252A

US3779252A - Tobacco stream manufacture

Info

Publication number: US3779252A
Application number: US00177740A
Authority: US
Inventors: W Brackmann; Ianni D Di
Original assignee: Rothmans Of Pall Mall
Current assignee: Rothmans Benson and Hedges Inc
Priority date: 1971-03-25
Filing date: 1971-09-03
Publication date: 1973-12-18
Anticipated expiration: 1990-12-18
Also published as: US4005717A

Abstract

A tobacco manipulating apparatus for formation of a tobacco filler rod for use in the formation of cigarettes includes a relatively thin and flat chute, a tobacco particle gatherer located adjacent the discharge of the chute and a relatively flat elongated conveyor to receive tobacco from the gatherer. The gatherer includes a plurality of rotatable discs mounted across the width of the chute and each having substantially the same diameter and including a tobacco receiving peripheral surface in the plane of the chute. A source of vacuum is connected to each disc and vacuum interrupter is provided to prevent the application of vacuum over part of the surface of each disc. In this way a plurality of narrow substreams is formed from a broad stream of such particles in the chute. The narrow substreams are deposited sequentially and tangentially of the discs into the filler rod on the conveyor, the discs being mounted so that a straight line through their axes of rotation is inclined in a downstream direction with respect to the conveyor.

Description

United States Patent [1 1 Brackmann et al.

[ 1 Dec. 18, 1973 1 TOBACCO STREAM MANUFACTURE [73] Assignee: Rothmans of Pall Mall Canada Limited, Toronto, Ontario, Canada [22] Filed: Sept. 3, 1971 [21] Appl. No.: 177,740

Related US. Application Data [63] Continuation-impart of Ser, No. 128,412, March 26,

1971, abandoned.

[52] US. Cl. 131/84 B, 131/110 [51] Int. Cl. A24c 5/18 [58] Field of Search 131/21 B, 21 D, 84 R, 131/84 A, 84 B, 84 C, 110

[56] References Cited UNITED STATES PATENTS 3,196,880 7/1965 Pinkham 131/84 R 3,094,127 6/1963 Gamberini 131/84 B X 3,490,463 1/1970 Richter 131/21 D X 3,173,424 3/1965 Gamberini 131/84 C 3,277,897 10/1966 Gamberini 131/22 R 3,030,965 4/1962 Lahbe 131/84 B X FOREIGN PATENTS OR APPLICATIONS 1,068,663 5/1967 Great Britain 131/84 B 813,576 5/1959 Great Britain 131/84 B Primary Examiner.loseph S. Reich AII0rne vSim & McBurney [57] ABSTRACT A tobacco manipulating apparatus for formation of a tobacco filler rod for use in the formation of cigarettes includes a relatively thin and flat chute, a tobacco particle gatherer located adjacent the discharge of the chute and a relatively flat elongated conveyor to receive tobacco from the gatherer. The gatherer includes a plurality of rotatable discs mounted across the width of the chute and each having substantially the same diameter and including a tobacco receiving peripheral surface in the plane of the chute. A source of vacuum is connected to each disc and vacuum interrupter is provided to prevent the application of vac uum over part of the surface of each disc. In this way a plurality of narrow substreams is formed from a broad stream of such particles in the chute. The narrow substreams are deposited sequentially and tangentially of the discs into the tiller rod on the conveyor, the discs being mounted so that a straight line through their axes of rotation is inclined in a downstream direction with respect to the conveyor.

4 Claims, 4 Drawing Figures PATENTED DEC 1 8 I975 SHEET 10F 2 INVE/V'EORS WARREN D. BRACKMANN DANIEL DHANNI PATENTEI] DEC 18 I975 SHEET 2 OF 2 INVENTORS WARREN D. BRACKMANN DANIEL DilANNI TOBACCO STREAM MANUFACTURE This application is a continuation in part of application Ser. No. 128,412 filed March 26, 1971 now abandoned.

This invention relates to tobacco manipulation apparatus, for use in the formation of a tobacco rod.

In the conventional modern method of formation of tobacco rods, generally for use as a filler for cigarettes, a relatively broad stream of tobacco particles of varying sizes, usually approxiamtely 36 inches wide, first is provided. This stream usually is rendered as even as possible by various means. The broad stream is thin and is gathered together in suitable manner to form a narrow stream of tobacco particles which is built up along its length by particles from the broad stream to form a continuous tobacco rod. Cigarettes are formed from the rod usually by lateral compression, followed by wrapping in paper, after which individual cigarettes are cut from the continuous cigarette rod.

Typically the broad stream of tobacco particles is gathered to form the narrow tobacco rod by allowing the broad stream to fall onto a narrow belt moving substantially perpendicularly to the direction of movement of the broad stream. The particles in the broad stream thereby are subjected to an abrupt lateral component of motion. The belt may have a substantially flat gathering surface. Alternatively, the belt may have a trough-like form.

To reduce the tendency of tobacco particles to be displaced longitudinally of the narrow stream in a direction opposite to the direction of movement of the narrow belt, thereby forming knots or balls of particles in the forming narrow stream, it has become common practice to construct the narrow belt of air-permeable material and to apply a gentle vacuum through the surface. This use of a gentle vacuum has been thought to grip the tobacco particles to the surface of the belt upon contact thereby diminishing the tendency of the narrow stream to ball up.

Close examination by high speed photography of the gathering of the falling broad stream into a narrow stream of tobacco particles has revealed that, while the gentle vacuum is to a certain degree effective in preventing displacement of the particles in those portions of the conveyor where the narrow stream is relatively thin, in thicker portions considerable peaks and valleys of tobacco particles in the forming stream occur since the effectiveness of the vacuum on the tobacco particles remote from the conveyor is diminished. The tobacco rod therefore lacks uniformity of quantity of tobacco in the cross section thereof. This may give rise to unsatisfactory finished products.

It was also observed that there was a marked tendency for longer tobacco particles to be aligned axially in the tobacco rod. The filling power of a cigarette filler rod is important to the economics of cigarette manufacture and axial alignment of longer tobacco particles provides a tobacco rod which does not have as high filling power as one in which at least a proportion of the longer tobacco particles are radially aligned.

The above-mentioned close examination additionally indicated that smaller particles tend to penetrate the surface of the portions of the stream already present on the conveyor belt while larger particles lie on the surface. In effect there is a classification of tobacco particle sizes over the cross section of the rod, with smaller particles tending to be located closer to the conveyor belt and larger particles tending to be located remote from the belt.

One effect of this classification is that bad ends to the cigarettes may result, together with uneven burning rates and uneven burning temperatures. with accompanying effects on smoke constituents and taste.

Because of the lack of uniformity of the quantity of tobacco in the cross section of the rod, it is common practice to provide the rod having peaks which contain more tobacco than is required in the final cigarette and to trim the excess tobacco, generally about 20 percent of the total tobacco in the rod, from the rod. It often is desirable to form cigarettes having a higher density of tobacco at the ends than elsewhere. A number of methods have been practised and suggested to provide such denser ends, generally associated with the trimming operation.

In addition to the formation of a tobacco rod from a falling broad stream of tobacco particles, tobacco rods are formed from broad streams of particles which are projected upwardly in a tunnel by air flow. The particles are gathered on the underside of an air-permeable tobacco impermeable belt moving transverse to the direction of movement of the broad stream. The tobacco particles are held on the undersurface of the belt by suction through the belt.

The present invention is applicable to both the formation of tobacco rods from downwardly flowing and upwardly flowing broad streams of tobacco particles.

In accordance with the present invention, a tobacco manipulating apparatus is provided in which a plurality of narrow substreams of tobacco particles are formed from the broad stream and the narrow stream is assembled from the substreams.

There has previously been described in U.S. Pat. No. 3,034,514 an apparatus for forming narrow substreams from an upwardly flowing broad stream and subsequently assembling the narrow stream from the substreams. In one embodiment of the apparatus described in the above-mentioned U.S. patent, a plurality of flat discs having circumferential air-permeable but tobacco impermeable perforations are mounted for rotation about vertical axes, so that .arcuate lengths of the discs are positioned in the path of movement of the upwardly flowing stream.

Thin substreams of tobacco are captured on the arcuate lengths and are transported upon rotation of the discs out of the path of movement of the broad streams. Upon release of the vacuum holding the substreams to the discs, the substreams fall onto a conveyor and form a narrow stream.

While a plurality of overlapping rotating discs is provided in this embodiment, there exist gaps between the overlapping discs through which tobacco particles from the broad stream may pass. Therefore, some of the tobacco particles of the broad stream proceed past the discs and are sucked into the air circulating system. The presence 'of these particles in the air circulating system may cause problems. As will become more apparent hereinafter, the apparatus of the present invention does not suffer from this defect. In the apparatus of the invention, the substreams are formed on surfaces positioned in the path of the normal flow of the broad stream towards the conventional forming zone. If gaps exist between the surfaces in the apparatus of the present invention, this is of no significance since the small number of particles passing through such gaps will be captured on the conveyor in the forming zone.

In another embodiment described in the U.S. patent, a plurality of shallow cylindrical wheels are positioned in the path of the upwardly flowing broad stream of tobacco particles, and mounted for rotation about horizontal axes. The wheels have recessed perforated walls which are air-permeable and tobacco impermeable. Each wheel rotates in an opposite direction to those adjacent thereto. Tobacco is captured on the wall of each disc, and the captured tobacco is passed from disc to disc across the width of the broad stream to form a narrow stream on the upper surface of a conveyor.

In the latter embodiment, substreams are only formed on some of the discs, but on others of the discs, the same problems exist as are inherent in the prior art as is discussed above. Since the wheels rotate in opposite directions, and the tobacco particles captured on one surface are transferred to the surface of an adjacent wheel, at least some of the wheels will have facing the broad stream, a surface which already has tobacco particles thereon. Therefore, the same problems of classification and balling up as discussed above would be encountered on these wheels. This embodiment therefore does not solve the existing prior art problems.

The embodiments described in this U.S. Patent also have another serious defect. As has been indicated above, in the modern cigarette-making machines, when the narrow stream is formed from a upwardly flowing broad stream, the narrow stream is formed on the underside of an air-permeable conveyor, and when the narrow stream is formed from a falling broad stream, the narrow stream is formed on the top surface of an air permeable conveyor. It will be observed that in both the embodiments of U.S. Pat. No. 3,034,514 described above, the narrow stream is provided on the upper surface of the conveyor.

The present invention is described further by way of illustration with reference to the accompanying drawings, in which:

FIG. 1 is a sectional schematic representation of a tobacco rod-making apparatus in accordance with one embodiment of the invention;

FIG. 2 is a sectional schematic representation of a tobacco rod-making apparatus in accordance with another embodiment of the invention;

FIG. 3 is an elevational view, with parts cut away of a gatherer in accordance with the present invention;

and

FIG. 4 is a section taken on line 4-4 of FIG. 3. off

With reference to FIG. 1, a tobacco manipulating apparatus includes a substantially vertically aligned chute 12 confining a falling broad stream 14 of tobacco particles of varying particle sizes. The falling broad stream 14 may be provided in any convenient manner. For example, a shower of tobacco particles may be sprayed onto the top surface of a conveyor belt to form on the belt a borad stream of tobacco particles. This broad stream is conveyed on the belt to the end thereof, at which point particles fall of the conveyor and form the falling stream or curtain 10.

A conveyor belt 16 is positioned below the chute 12 and is adapted to move transverse to the chute l2. Generally, the belt 16 moves at a speed substantially in excess of the speed'of the falling particles.

A plurality of control wheels or

discs

18, 20, 22 and 24, shown in section, are positioned adjacent to and spaced from the top surface of the belt 16. The wheels are positioned between the walls of the chute l2 and are located in the path of the falling stream 14.

In the embodiment illustrated the

control wheels

18, 20, 22 and 24 each are positioned in a single plane to rotate in an anti-clockwise direction on horizontal axes which are parallel to each other and transverse to the plane in which the broad stream 14 falls. Additionally, the wheels are located with their axes of rotation located in a plane parallel to the plane of the conveyor top surface. As described below, it is not essential to provide the horizontal axes in the plane parallel to the plane of the top surface of the conveyor 12. It is possible to stagger the locations of the

wheels

18, 20, 22 and 24 from this configuration while maintaining the wheels in the path of the falling stream 14.

The

wheels

18 and 20 are of identical construction and a typical construction is more particularly described below with reference to FIG. 4. Each

wheel

18 and 20 is in the form of a hollow cylinder of shallow depth having a peripheral wall including an airpermeable tobacco impermeable surface 26 extending at least part way between the top and bottom of the cylinder. The surface 26 coconstitutes a narrow substream-forming surface. The porous peripheral surface 26 is positioned in the path of the stream 14 and rotates in the plane of the stream. A vacuum is applied to the interior of the

wheels

18 and 20 such as by a vacuumheader pipe 204 in FIG. 4, so that a considerable suction is applied through the surface 26.

Inside each of

wheels

18 and 20 and located adjacent the inside surface of the wheele is a non-porous fixed shield or

shoe

30 and 32 respectively. The

shoes

30 and 32 may be constructed in any convenient manner so that the suction applied to the surface 26 is released over those portions of the surface 26 adjacent the

shoes

30 and 32. The

shields

30 and 32 are illustrated as located within the

wheels

18 and 20 so that the vacuum is prevented from acting over the area of the surface 26 of the wheel which is located from approximately the point of nearest approach of the

wheels

18 and 20 to the top surface of the conveyor 16 through about in the direction of movement of the wheels. This configuration maybe varied as desired.

As the tobacco particles in the stream 14 fall towards the conveyor 16, they are arrested by the suction acting over the porous surface 26 when vacuum is induced within the

wheels

18 and 20. A narrow substream of tobacco particles 34 builds up on each of the surfaces 26 as the

wheels

18 and 20 rotate anti-clockwise, the narrow substream having increasing depth in the direction of movement of the wheels as the quantity of tobacco builds up. Preferably, wheels, 18 and 20 rotate at the same speed but it is possible to provide different speeds of rotation, if desired.

When the narrow substream 34 on wheel 18 reaches the shield 30, the substream no longer is held by the vacuum and therefore the particles of the substream fall from the surface 26 onto the top surface of the conveyor 16. Generally, the

wheels

18 and 20 are positioned close to the conveyor 16, so that the substream 34 is laid gently on the top surface of the conveyor 16, thereby avoiding disturbance of the relative locations of the tobacco particles in the substream 34. As the conveyor generally is moving with considerable speed to the right as shown by the arrow in FIG. 1, then a degree of displacement of the substream 34 occurs in the direction of movement of the conveyor surface as it is deposited on the surface, as illustrated.

Similarly, when the narrow substreams 34 on wheel reaches the shield 32, then the narrow substream 34 of tobacco particles is laid gently on top of the existing stream which was laid from the wheel 18. The wheels may rotate at any convenient speed relative to the speed of the top surface of the conveyor 16. Generally, the speed of rotation of the

wheels

18 and 20 and linear speed of the conveyor belt 16 are substantially the same so that there is little or no relative speed between the tobacco particles in the substreams 34 and the conveyor 16 when the particles are laid on the conveyor surface.

The rotational speed of the

wheels

18 and 20 and the linear speed of the conveyor 16 however may vary from each other so that the substream of tobacco particles is lengthened or shortened on the conveyor belt relative to its length on the surfaces 26, as desired. If the top surface of the conveyor 16 moves faster than the rotational speed of the wheels, then the substreams 34 are stretched, whereas if the top surface of the conveyor 16 moves slower than the rotational speed of the wheels, then the substreams 34 are abbreviated.

The speed of rotation of

wheels

18 and 20 is dependent on the quantity of tobacco desired in the narrow substreams 34 formed on the surface thereof. At lower speeds of rotation, larger quantities of tobacco are deposited on the surfaces 26 and, therefore, the substreams placed on the conveyor 16 are thicker, whereas at higher speeds rotation lower quantities of tobacco are deposited on the surfaces 26 and the substreams placed on the conveyor are thinner. The degree of vacuum applied over the inner surface of the wheels also may be varied as required.

The

wheels

18 and 20 therefore control the velocity of approach of the tobacco particles from the falling broad stream 14 to the conveyor 16 by the formation of substreams. The tobacco particles of the broad stream 14 thereby move from one direction to a second direction lateral to the first direction in smooth manner. stream 36 on the top surface of the conveyor 16 has been illustrated utilizing two wheels, so that the tendencies of classification of the particles and the formation of peaks and valleys are reduced. This manner of illustration is a matter of convenience and it is preferred in the present invention to employ more than two such wheels. The actual number of wheels of the

type

18, 20 used depends on a number of factors, including the characteristics desired in the finished rod, the width of the broad stream 14 and the distance between the top surface of the conveyor and the source of the broad stream 14. An arrangement of wheels of typical number is described below with regard to the showing in Fig. 3.

As the narrow substreams 34 are formed on the porous surfaces 26 of the wheels 18, 20 a minor degree of classification and peak-and-valley formation may occur on each wheel. If a plurality of wheels is provided and a narrow substream of small ultimate depth is formed on each such wheel and the narrow stream 36 is formed from the plurality of narrow substreams, then the stream 36 in effect is formed ofa plurality of layers of tobacco particles. The final rod stream 38 formed in this manner has a substantially uniform quantity of to bacco in the cross section thereof, and additionally has a substantially uniform distribution of particle sizes over the cross section.

The wheels of the

type

18, 20 are spaced from the top surface of the conveyor 16 any desired distance. As indicated above, generally the distance is such that the substreams are gently laid one on top of the other.

The present invention also provides apparatus with wheels of construction other than

wheels

18, 20 described above. Wheel 22 is of similar construction to

wheels

18 and 20 and is provided with a peripheral wall including an air-permeable tobacco impermeable surface 40 in similar manner to

wheels

18 and 20. A vacuum is applied to the interior of the wheel to provide a suction through the porous surface 40. Inside the wheel 22 and located adjacent the inside surface thereof is a non-porous fixed shield or shoe 44 which has a semicircular cross section. The shield 44 extends approximately from the ends of the diameter of the wheel 22 parallel to the conveyor 16 through the lower half of the wheel. As in the case of

shoes

30 and 32, shoe 44 may be constructed in any convenient manner so that the suction is released over the semi-circular portion of the surface 40 adjacent the shoe at any particular time. The shoe 44 may extend over any convenient arcuate length of the wheel 22, provided that the function of the wheel is achieved.

Tobacco particles from the falling stream 14 are captured by the surface 40 and form a narrow substream 46 of tobacco particles on the surface 40 of increasing depth in the direction of rotation of the wheel 22. As mentioned above in connection with the conventionally formed narrow stream, the longer strands of tobacco tend to be oriented generally in the direction of the narrow substream 46.

The wheel 22 rotates at a fast speed relative to the rate of flow of the broad stream 14 and generally at approximately the speed of the conveyor 16. The relative speeds of the wheel 22 and the conveyor 16 may be varied as desired.

As the wheel 22 rotates anti-clockwise, tobacco particles are projected from the substream 46 at the shield 44 towards the narrow stream 36. A single wheel of the type 22 is illustrated. It may be desired under certain circumstances to use more than one wheel of this type in conjunction with or in the absence of wheels of the

type

18, 20.

A further construction of wheel in accordance with this invention is wheel 24. The wheel 24 is of similar construction to

wheels

18 and 20 including a cylinder having a peripheral wall including a partially porous surface 48'. The surface 48 is provided with porous portions 50 which are positioned at spaced intervals around the periphery. The porous portions may be provided at any convenient intervals, typically at to each other. Vacuum is applied to the interior of the wheel 24 thereby producing a suction through the porous portions 50 of the surface 48.

Located inside the wheel 24 is a non-porous fixed shield or shoe 54, which extends from approximately the closest point of approach of the surface 48 to the top surface of the conveyor 16 through 90 in the direction of movement of the wheel 24. The shoe 54 may be of any convenient form to release the suction applied through those portions of the porous surface 50 from time to time adjacent thereto.

As the stream of particles 14 falls towards the surface 48, some of the particles are arrested by the action of the vacuum on the porous areas 50 thereby forming a plurality of spaced-apart substreams 56 on the surface 48.

When one of the porous portions 50 of the wheel 24 has rotated to reach the shild 54, the particular substream adjacent the shield is deposited on the stream 36, thereby providing areas of increased cross-sectional quantity along the stream 36. These areas of increased quantity in the cross section are the basis for dense ends in the final cigarette. During the later manufacturing steps to form the cigarettes, the rod 38 is compressed to form a rod of uniform diameter, but due to the presence of larger quantities of tobacco at selected spaced-apart positions along the length of the rod, the uniform diameter rod formed after compression has spaced-apart denser areas, which are positioned equivalent to one or both ends of cigarettes formed from the rod. It will be seen, therefore, that the present invention is able to achieve dense ends without the necessity for complicated trimming techniques.

The speed of rotation of wheel 24 and the number of openings 50 in the surface 48 may be selected to provide for depositing the required number of substreams 56 at the required lcoations equivalent to the one or two lumps of tobacco to be located at spaced-apart locations on the rod 38.

Where it is desired to employ a wheel of the type 24, only one usually is required, although it is possible to provide more than one such wheel, if desired. Such wheel 24 may be used in combination with a plurality of the wheels of the type 18, with or without the presence of one or more wheels of the type 22. It is possible to use a wheel 24 in conjunction with or separate from

wheels

18, and 22.

It is possible that the stream 36 formed from the substreams 34 may have valleys therein, so that the quantity of tobacco in the cross section of the assembled rod 38 is not constant.

The apparatus described above with reference to FIG. 1 may be varied to achieve different functions. The particular functions chosen are suited to local requirements and depend on a number of factors, such as tobacco costs, type of tobacco and the nature of the market.

The wheels may be spaced apart as desired so that any given quantity of tobacco may fall directly onto the conveyor 16 without being subjected to manipulation by the wheels.

It is not necessary to provide a flow of tobacco particles in the stream 14 which is evenly distributed over its width. By maintaining a substantially fixed configuration of flow it is possible to maintain a consistent end product rod 38.

Further, the vacuum may be provided over differing portions of the surfaces of the wheels from that illustrated and described above.

Further, it is not necessary that the shoes located within the wheels extend throughout the arcuate distance indicated. It is possible to provide the vacuum cut-off point at any convenient position, for example, in

wheels

18, 20 and 24 for deposition of the tobacco onto the conveyor or onto tobacco already deposited on the conveyor. Further, the vacuum shoe may extend any desired arcuate distance from the cut-off point, varying as desired from the approximately 90 for

wheels

18, 20 and 24 and the approximately 180 for wheel 22.

Turning now to FIG. 2, which illustrates a second embodiment of the invention. This embodiment is similar to that of FIG. 1 with the exception that the apparatus is concerned with the formation of a tobacco rod 112 from an upwardly flowing broad stream 114 of tobacco particles. The upwardly flowing broad stream 114 is confined in a chute 110 and projected by an upward flow of air induced by any convenient means, not

shown.

A narrow tobacco stream 118 is formed on the underside of a conveyor belt 120 and is held there by suction applied through the belt 120 by means not shown.

Typical apparatus in which a tobacco filler rod is formed on the underside of a belt from an upwardly flowing stream is shown in U.S. Pat. Nos. 3,030,965 and 3,089,497, and the present invention represents a modification of such apparatus.

In the apparatus of FIG. 2, a plurality of

wheels

122, 124, 126 and 128 is provided adjacent the underside of the belt 120 in the path of the broad stream of particles 114.

The construction and function of the

wheels

122, 124, 126 and 128 is the same as that of

wheels

18, 20, 22 and 24 respectively described above with reference to FIG. 1 and further description does not appear necessary. The modifications of the construction and orientation of the

wheels

18, 20, 22 and 24 described above apply equally to

wheels

122, 124, 126 and 128.

It will be seen that the tobacco substreams formed on the

wheels

122, 124, 126 and 128 are deposited on the underside of the conveyor belt 120. The wheels thus improve the manner of formation of the final rod 112, but do not alter the basic configuration of the rodmaking apparatus, in that an upwardly flowing broad tobacco stream is deposited on the underside of the belt 120. The wheels therefore are readily utilizable in existing modern tobacco manipulating equipment, such as that described in the above-mentioned US. Pat. Nos, 3,030,965 and 3,089,497.

It will be seen that this arrangement is in contrast to that shown in 1.1.5. Pat. No. 3,034,514 wherein the tobacco in the upwardly flowing broad stream is deposited on the upper surface of the conveyor.

Referring to FIG. 3, there is shown a typical gatherer 200 including a plurality of wheels for use, for example, in a tobacco rod-making apparatus, such as illustrated schematically in FIGS. 1 and 2 The gatherer 200 includes a frame 202 which extends across the width of the broad stream and is secured in any convenient manner to the chute containing the broad stream. The frame 202 has secured thereto a vacuum header 204 which extends across the width of the frame. The header 204 is in communication with a plurality of

discs

206, 208. All of the discs 206 are of the type 18 (FIG. 1) and the disc 208 is of the type 24 (FIG. 1). These

discs

206 and 208 are mounted for rotation in the frame as indicated below.

As shown in schematic broken outline, drive for the

discs

206 and 208 is provided by a single motor 210, which drives all of the discs 206 by a continuous belt 212 which engages each of the discs 206 and passes over idler wheels 214. While idler wheels 214 are only illustrated as being located between selected discs 206, the wheels 214 are located between each adjacent pair of discs 206.

A belt 216 and idler wheel 218 achieve the required drive for disc 208. A narrow stream forming conveyor 220 is located beneath the

discs

206, 208. The conveyor 220 is air permeable and suction is applied through the surface of the conveyor 220. Generally there is a high air flow through the conveyor surface while the pressure drop is low.

As may be seen from FIG. 3, the discs 206 are positioned successively a greater distance from the conveyor belt 220 in the direction of intended motion of the belt 220. The left-most disc 206 is positioned a predetermined distance from the conveyor belt 220 so that the substream thereon may be gently laid on the belt 220, the substream when on the belt 220 being substantially tangential to the disc 220. Each successive disc 206 from left to right is spaced from the conveyor 220 a distance when the gatherer 200 is in use, from the top surface of tobacco already positioned on the belt 220, substantially equal to the predetermined distance of disc 206. In this way, the substream from each of these discs is laid gently on the existing stream on the conveyor 220, the substream in each case when laid on the existing stream being substantially tangential to the appropriate disc 206.

As shown more particularly in FIG. 4, each of the discs 206 is in the form of a cylinder 222 which is mounted on a circular flange 223 of a hub 224. The hub 224 is journalled by bearings 225 for rotation about a normally stationary hollow axle 226.

The cylinder 222 has a plurality of openings 228 formed in the wall thereof and a foraminous air permeable, tobacco impermeable screen 230 is seated in a channel 232 in the wall of the cylinder 222 covering the openings 228. The cylinder 222 is mounted for rotation on the axle 226 in a housing consisting of opposed parts 234 and 236. The parts 234 and 236 cooperate to provide an open circumferential channel 238 coinciding with the screen 230. The channel 238 has sloping walls to guide errant tobacco particles onto the screen 230.

A sprocket wheel 240 is mounted on the hub 224 and engages the belt 212 so that the wheel 240, hub 224 and disc 206 are rotated about the axle 226, upon actuation of the motor 210.

The hollow axle 226 is mounted in friction fit in a bushing 242 located in a support frame 244 which includes part 234. The support frame 244 is connected to the frame 202 of the gatherer 200. At its other end the axle 226 is mounted in friction fit in a bushing 246 which is located in a bracket 248 integral with part 236. The friction fits between the axle 226 and the

bushings

242 and 246 allow the axle 226 to be rotated on its axis if sufficient force is applied to overcome the frictional forces. A hexagon nut 250 or other convenient gripping means is mounted on the axle to achieve the desired rotation. The friction fit prevent the axle 226 from rotating when the hub 224 is rotated.

The axle 226 is formed integral with a vacuum shoe 252 which extends around the inner periphery of the wall of the disc 206 any desired angular distance.

The axle 226 is formed with a hollow bore 254 which extends from an air relief opening 256 in the nut 250 to the shoe 252. The shoe 252 is provided with a passageway 258 in fluid communication with the bore 254 the passageway 258 terminating at the peripheral surface of the shoe. The passageway 258, bore 254 and opening 256 allow air to pass to the portion of the screen 230 opposite the opening 260 to the passageway 258.

The vacuum header pipe 204 communicates directly with the interior of the cylinder 222 and an integral part thereof constitutes the part 236. Hence, when vacuum is applied to the header pipe, suction is applied through the openings 228 through the screen 230, except over those portions of the screen 230 opposite the vacuum shoe 252. The cylinder 222 rotates in a channel 262 in the part 236. In order to avoid wear to the abutting surfaces of the cylinder 222 and the channel 262, a fluid tight seal is not provided and passageways 264 are provided to leak air through the small gap 266 between the inner annulus of the channel and the disc 206.

The disc 208 is of substantially the same construction as disc 206, except that its screen 230 is provided with perforations only at spaced-apart peripheral locations.

The gatherer 200 is positioned in the path of movement of a falling broad tobacco stream. It will be apparent that only minor modifications are required so that the gatherer 200 may be used with an upwardly flow broad tobacco stream. The axes of rotation of the

discs

206 and 208 are horizontal and perpendicular to the path of movement of the broad stream. With the motor 210 operating and vacuum applied to the header 204 the tobacco particles are trapped by the screen 230 and form narrow substreams on the screen 230. The narrow substreams on the discs 206 are released by the air bleed through opening 260 and fall onto the conveyor 220 which is moving to the right as seen in FIG. 3. In the manner described with reference to FIGS. 1 and 2, a tobacco rod is built-up. The disc 208 provides local areas of increased quantity of tobacco to provide ultimately dense ends to the product cigarettes.

It will be seen, therefore, that the present invention provides apparatus which manufatctures an improved tobacco filler rod. In view of the improvements in the characteristics of the tobacco filler rod formed in the present invention as compared to the rod formed by conventional means, cigarettes may be produced having a more consistent and improved quality.

The above-described specific embodiments of the invention represents only examples of the manner in which control of the formation of the narrow tobacco stream may be achieved to suit individual requirements. Other manner of achieving this control are possible and many modifications are possible within the scope of this invention.

What is claimed is:

1. A tobacco manipulating apparatus which comprises means to feed a broad stream of tobacco particles, gathering means comprising a plurality of shallow cylindrical discs positioned adjacent a discharge end of said feed means to collect and convey a plurality of narrow tobacco substreams, each of said discs having substantially the same diameter and having a peripheral wall including an air-permeable, tobacco-impermeable surface and being rotated about its axis, each of said walls having an external surface to form a narrow substream of tobacco particles from said broad stream, each of said discs being hollow and the interior thereof having a pressure that is less than atmospheric, vacuum interrupting means positioned to prevent the application of said pressure over a selected arcuate length of each of said peripheral surfaces; and a conveying surface located adjacent said gathering means outside of said feed means to receive said plurality of tobacco substreams from said gathering means to form thereon a narrow stream of tobacco particles; a straight line joining the axes of rotation of said plurality of discs being inclined with respect to the conveying surface such that the substreams received from each of said discs onto the conveying surface is substantially tangential to said disc and to the top surface of said narrow stream.

2. The apparatus of claim 1 wherein said vacuum interrupting means is located internally of each of said discs and extends over an arcuate length of each of said peripheral surfaces from the approximate point of nearest approach of said peripheral surface to said conto apply vacuum through said conveying surface.

Claims

2. The apparatus of claim 1 wherein said vacuum interrupting means is located internally of each of said discs and extends over an arcuate length of each of said peripheral surfaces from the approximate point of nearest approach of said peripheral surface to said conveying surface.

3. The apparatus of claim 1 wherein one of said plurality of discs is provided with a peripheral surface having arcuately spaced apart air-permeable portions and said vacuum interrupting means is located internally of said disc and extends over an arcuate length of said peripheral surface from the approximate point of nearest approach of said peripheral surface to said conveying surface.

4. The apparatus of claim 1 including vacuum means to apply vacuum through said conveying surface.