US3915177A - Tobacco manipulating machines - Google Patents

Abstract

A cigarette filler rod forming apparatus includes an enclosed relatively thin and flat elongate passage defined by side and end walls having an inlet opening at the lower longitudinal extremity thereof, a tobacco gathering means enclosing the upper longitudinal extremity thereof and a relatively flat elongated foraminous conveyor positioned adjacent the gatherer to which suction is applied to receive tobacco therefrom. The gatherer includes a plurality of discs mounted across the width of the passage with their axes perpendicular to the side walls and each having substantially the same diameter. Each disc includes a peripheral wall extending between the side walls and including a continuous air-permeable tobacco-impermeable surface rotatable about the axis of the discs in the same direction at substantially the same speed. Each of the discs is hollow and vacuum is applied internally thereof to cause air to move continuously through the passage as a high velocity stream from the inlet towards the gatherer and to convey substantially separated tobacco particles towards the gatherer. A vacuum interrupter is provided internally of each disc to prevent the application of suction over part of the foraminous surface of each disc not intercepting the tobacco particles conveyed in the high velocity air stream. The vacuum interrupter is positioned to allow release of tobacco particles at approximately the point of nearest approach of the discs to the conveyor. In this way, a plurality of narrow substreams of tobacco is formed from the particles conveyed in the high velocity stream on the substream forming portion of the foraminous surface intercepting the particles and the narrow substreams are deposited sequentially on the conveyor to form the filler rod. In a preferred embodiment, the discs are 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.

[ *Oct. 28, 1975 TOBACCO MANIPULATING MACHINES [75] Inventors: Warren A. Brackmann, Cooksville;

Daniel DiIanni, Toronto, both of Canada [73] Assignee: Rothmans of Pall Mall Canada Limited, Toronto, Canada Notice: The portion of the term of this patent subsequent to Dec. 18, 1990, has been disclaimed.

[22] Filed: Aug. 2, 1974 [21] Appl. No.: 494,094

[30] Foreign Application Priority Data Aug. 22, 1973 United Kingdom 39875/73 [52] U.S. Cl. 131/84 B; l3l-/l10 [51] Int. Cl. A24C 05/18 [58] Field of Search.... 131/21 D, 84 R, 84 B, 84 C, 131/110 [56] References Cited UNITED STATES PATENTS 3,030,965 4/1962 Labbe 131/110 X 3,094,127 6/1963 Gamberini.. 131/21 D 3,196,880 7/1965 Pinkham 131/84 R 3,779,252 12/1973 Brackmann et al. 131/84 B FOREIGN PATENTS OR APPLICATIONS 1,068,663 5/1967 United Kingdom 131/84 B 813,576 5/1959 United Kingdom 266,385 10/1913 Germany 131/110 Primary ExaminerJoseph S. Reich Attorney, Agent, or F irm-Sim & McBumey [57] ABSTRACT A cigarette filler rod forming apparatus includes an enclosed relatively thin and flat elongate passage defined by side and end walls havingan inlet opening at the lower longitudinal extremity thereof, a tobacco gathering means enclosing the upper longitudinal extremity thereof and a relatively flat elongated foraminous conveyor positioned adjacent the gatherer to which suction is applied to receive tobacco therefrom. The gatherer includes a plurality of discs mounted across the width of the passage with their axes perpendicular to the side walls and each having substantially the same diameter. Each disc includes a peripheral wall extending between the side walls and including a continuous air-permeable tobacco-impermeable surface rotatable about the axis of the discs in the same direction at substantially the same speed. Each of the discs is hollow and vacuum is applied internally thereof to cause air to move continuously through the passage as a high velocity stream from the inlet towards the gatherer and to convey substantially separated tobacco particles towards the gatherer. A vacuum interrupter is provided internally of each disc to prevent the application of suction over part of the foraminous surface of each disc not intercepting the tobacco particles conveyed in the high velocity air stream. The vacuum interrupter is positioned to allow release of tobacco particles at approximately the point of nearest approach of the discs to the conveyor. In this way, a plurality of narrow substreams of tobacco is formed from the particles conveyed in the high velocity stream on the substream forming portion of the foraminous surface intercepting the particles and the narrow substreams are deposited sequentially on the conveyor to form the filler rod. In a preferred embodi ment, the discs are mounted so that a straight line through their axes of rotation is inclined in a downstream direction with respect to the conveyor.

4 Claims, 3 Drawing Figures US. Patent 0a. 28, 1975 3,915,177

| IIIIIJII 1 TOBACCO MANIPULATING MACHINES FIELD OF INVENTION The present invention is directed to tobacco manipulating machines.

BACKGROUND TO THE INVENTION A long known difficulty in the cigarette making art has been the irregularity in the formation of a filler rod which is caused by showering tobacco by gravity onto a travelling surface in such a way that tobacco already on the surface is actually moving past the falling tobacco. That condition results in irregularities because any upstanding or projecting parts of the filler or stream, such as is caused by the deposition of lumps of tobacco in the stream, tend to intercept falling tobacco particles, thus causing undue accumulation of tobacco in front of and on top of such projecting parts, with corresponding sparsity of tobacco immediately behind such parts. This result may be termed the peak and valley" or shadow effect.

The resultant filler rod has a complete lack of uniformity of quantity of tobacco in the cross section thereof along its length, which produces cigarettes of nonuniform quality, which is unacceptable.

One prior art suggestion is overcome or at least minimize the problem appears in U.S. Pat. No. 3,030,965. In this patent, a tobacco filler rod is formed on a perforated conveyor band moving longitudinally thereof by means of a stream of air flowing at high velocity through a passage towards and through the conveyor band so as to carry tobacco particles through the passage in substantially separated form and to depositthe tobacco particles on the conveyor band. In this prior' art structure, the high velocity air stream is wholly confined laterally by the passage, and' all the air which flows through the passage leaves the passage by flowing through the perforated conveyor band and through the tobacco on the conveyor band.

Thus, most of the tobacco particles reaching the conveyor band do soin the form of separate particles and lumps of tobacco are substantially absent from the stream. The tobacco filler rod built up on the conveyor band by the arrival of these substantially separated particles is subjected to the minimum disturbance during its formation, since an individual particle has insufficient mass to create any significant disturbance or displacement of tobacco already on the conveyor band.

In addition, in the preferred operation of the apparatus of U.S. Pat. No. 3,030,965, the tobacco particles which on reaching the conveyor band are moving up with substantially the speed of the air which carries them less the reduction in speed due to gravity, reach the conveyor band or the partly-formed filler rod carried thereby with substantially no movement relatively to the conveyor band considered in the direction of movement of the band. Thus, the effect is the same as if the conveyor band were stationary and the tobacco particles travelled to it in directions substantially normal to the band. In this way, the peak-and-valley or shadow effect of the prior art technique is sought to be overcome and some improvement in the uniformity of weight of tobacco along the length of the tiller rod has been experienced.

However, the formation of filler rods using the apparatus of U.S. Pat. No. 3,030,965 produces filler rods which exhibit other defects. Due to the high velocity of impact of the individual tobacco particles on the partlyformed filler rod on the conveyor band and the porosity of the surface of the partly-formed rod, there is a tendency for some of the tobacco particlesto be buried in the partly-formed rod rather than lying on the surface of the partly-formed filler rod. Smaller tobacco particles have greater penetrative power than longer tobacco particles and the filler rod tends, therefore, to have a classification of tobacco particles sizes in its cross-section.

This classification effect leads to problems in later handling of the filler rod during the formation of cigarettes therefrom since the portion of the cross-section containing the higher proportion of small particles has a greater tendency to be detached from the ends of cigarettes than the portion of the cross-section containing the higher proportion of longer particles. The irregular fall-out of quantities of tobacco from the ends of cigarettes is clearly undesirable and should be avoided, if possible. In addition, to producing bad cigarette ends, the classification effect also may lead to uneven buming rates for the cigarette when smoked.

Another problem encountered by filler rods produced in the apparatus of U.S. Pat. No. 3,030,965 due to the high rate of impacting of tobacco particles together at the conveyor band is a limitation on the tilling power of the filler rods. The filling power of a filler rod is its ability to fill a paper cigarette tube. It is measured by determining the weight of tobacco required to produce a particular hardness of cigarette. The less tobacco necessary to provide the predetermined hardness of cigarette the greater is the filling power of the tobacco filler rod from which the cigarette is formed.

Consumer acceptance of cigarettes is based more on g the feel of a cigarette, i.e., its hardness, than on the absolute tobacco content of the cigarette. Thus, where a predetermined hardness of cigarette is desired, and that hardness is provided by less tobacco, i.e. from a filler rod of greater filling power, then manufacturing econorriies can be effected.

A further difficulty arises in the practical operation of the apparatus of U.S. Pat. No. 3,030,965. Thevelocity with which the air can be cause to flow up the passage and hence the speed of formation'of tobacco filler rod, is limited by the resistance offered to the air flow by the tobacco on the conveyor band and the resistance of the band itself. This problem has led to the positioning of openings in the side walls of the passage in the region of the conveyor band so that part of the air can escape from the passage and be separated from the tobacco while the latter continues to move towards the conveyor band with the remainder of the air. This structure is described in U.S. Pat. No. 3,019,793.

The side wall openings while improving the speed of operation also introduce other problems. The openings generally are provided in the form of guide elements or louvres which are inclined to the passage so as to guide air out of the passage in a rearward direction considered in the direction in which air moves through the passage. Operation of rod-forming machines having this structure has shown these machines to be sensitive to the air supply, the angle of inclination of the louvres and to normal operational variations. Unless these factors are properly balanced within very narrow tolerances, some loss of tobacco through the louvres and/or jamming of the passage by tobacco may occur. The

sensitivity in due to the necessity to achieve a clear separation of a considerable portion of the air passing through the passage into and through the louvers withoutaffecting the path of movement of tobacco to the conveyor band. This arrangement, further is incapable of affecting the classification and filling'power problems of the product from the apparatus of US. Pat. No;

An additional operating problem of the apparatus of U.S. Pat. No. 3,030,965 is described in U.S. Pat. No. 3,091,244. There is tendency for air to be drawn by suction from atmosphere through the gap between the filler rod and the end wall of the passage so as to enter the passage. The air which thus passes through the gap moves lengthwise of the filler rod against the direction of endwise movement of the tiller rod and this is found to have a disturbing effect on the formation of the filler rod by displacing tobacco lengthwise'of the filler rod, thereby introducing some lack of uniformity to quantity'of tobacco in the filler rod. In order to attempt to overcome this problem, as described in US. Pat. No. 3,091,244, closure means is located adjacent the end wall of the passage past which the conveyor carries the filler rod formed thereon in the passage. The closure means includes a part which engages the filler rod while cldsing the'gap between the end wall and the filler rod and is flexible to accommodate variation in depth of the filler rod. 7 Many different structures of closure means have been used on cigarette-making machines constructed in accordance with the principles of US. Pat. No. 3,030,965 and none has been found to be wholly satisfactory.

It will be apparent therefore that the prior art filler rod-forming apparatus of the type described in US. Pat. Nos. 3,030,965 and 3,019,793 suffers from drawbacks which limit the quantity of the cigarette product and the economics of the cigarette making operation, and which render operation a precise and delicate matter.

' SUMMARY OF INVENTION other than those required for removal of air through the gathering means.

The tobacco gathering means used in the present invention comprises a plurality of shallow cylindrical discs having their axes intersecting the side walls of the passage approximately at right angles thereto. Each 'disc has substantially the same diameter andhas a peripheral wall extending between the side walls and including and air-permeable, tobacco-impermeable foraminous surface, .Each disc'is hollow and vacuum is applied internally'so that suction is'applied through the foraminous surfaces.

The foraminous surfaces each may be rotated about its axis of the disc at substantially the same speed in the same direction. Vacuum interrupting means is positioned-to prevent the application of suction through a selected arcuate length of each of the foraminous surfaces.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic part sectional view of one embodiment of the invention; I

FIG. 2 is a sectional view taken on line 2-2 of FIG.

1; and

FIG. 3 is an elevational part sectional view of a detail of a gatherer for use in the embodiment of FIG. 1.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring to the drawings, a tobacco filler rod forming apparatus 10 includes a narrow passage 12 formed by side walls 14 and 16 and end walls 18 and 20 extending continuously from one end of the passage to the other. At the'top of the passage 12 an endless metal conveyor band 22 provided with perforations which are air permeable but tobacco impermeable passes over pulleys 24 and 26 with suitable adjustment being provided to take up slackness in the band.

The band: 22 extends directly beneath a suction chamber 28, the edges of the band 22 engaging shoulders formed on opposing members 30 which form a conduit 32leading to the suction chamber 28. This construction also is illustrated in US. Pat. No. 3,030,965.

In accordance with the present invention, the louvres illustrated in US. Pat. No. 3,019,793 and the closure means required in US. Pat. No. 3,091,244 are omitted and a tobacco gatherer 34 is positioned in the passage 12 in any convenient manner between the upwardlyflowing stream of air-and tobacco and the conveyor band 22.

The gatherer 34 comprises a plurality of shallow, hollow, cylindrical discs 36 extending substantially across the width of passage 12 and shown in more detail in FIGS, 2 and 3. Each disc 36 has a peripheral wall 38 with a continuous air-permeable tobacco impermeable foraminous surface 40 therein. Each of the surfaces 40 is mounted for rotation about the axis of the disc 36 by means not shown and has substantially the same diameter.

Vacuum is applied internally of each of the discs 36 in any convenient manner, not shown, whereby suction is applied through the foraminous surfaces 40. Openings usually are necessary in the side walls 14 and 16 to allow the application of vacuum. However, such openings clearly contrast with the openings described in US. Pat. No. 3,019,793 wherein the air is removed before the tobacco particles reach the conveyor. A vacuum interrupting shoe 42 is positioned internally of each disc 36 to prevent the application of suction through an arcuate length of the foraminous surface 40 which does not include the tobacco particles intercepting portion thereof. Preferably the shoe 42 extends from the approximate point of nearest approach of the foraminous surface 40 to the conveyor band 22 in the direction of intended motion of the surface 40.

In addition as shown in FIG. 3, the straight line join- .ing the axes 44 of the discs 36 preferably is inclined with respect to the conveyor band 22 for reasons discussed below in connection with the operation of the device.

The number of such discs 36 which may be used in thegatherer 34 may vary widely although about 6 to 8 are most useful. Usually, all the foraminous surfaces 40 are continuous, althrough it is possible to utilize one of the wheels 36 to provide dense ends in the cigarettes, if desired, by providing one of the peripheral walls 38 with accurately spaced-apart air-permeable portions only.

OPERATION In operation, a high speed'moving stream 46 of air and substantially spaced apart tobacco particles, is drawn upwardly through the passage 12 by the action of the suction internally of the surfaces 40 and into contact with the portion of the foraminous surface 40 of the rotating discs 36'intercepting the stream 46 and designated a substream forming surface. The tobacco particles may be fed into the stream 46 in any convenient manner, such as is described more fully in U.S. Pat. No. 3,030,965. The quantity of tobacco in the stream 46 usually is substantially uniform across the width thereof. The tobacco particles are fed to the inlet of the passage 12 in substantially separated form in any convenient manner, for example, as described in U.S. Pat. No. 3,030,965.

Under influence of the suction applied through the surface 40 of each disc 36, the tobacco particles in the moving stream in the passage 12 are gathered on the substream forming surface portion of the foraminous surfaces 40 to provide a narrow substream of tobacco 48 on each of the surfaces 40. A substream of tobacco, as used herein, is intended to refer to an elongated narrow stream of tobacco particles which itself is incapable of use as a filler rod to form cigarettes but which may be joined with other like streams to form a filler rod from which cigarettes may be formed.

The substreams 48 all usually contain the same quantity of tobacco. The depth of the substream 48 increases in its direction of motion, as illustrated, until the foraminous surface 40 conveys the substream under the influence of the suction out of contact with the stream 46. I

The substreams 48 have only a shallow depth and hence the classification of particle sizes discussed above in connection with the products of the apparatus of U.S. Pat. Nos. 3,030,965 and 3,01'9,793 is minimized or eliminated entirely. Further, since the surface 40 on which the substream 48 is formed is arcuate, then the combined length of tobacco receiving surface provided by the plurality of discs 36 is 1r/2 times the length of the conveyor band 22 in the path of the stream 46. This results in greater air-permeable surface area through which to pass the air.

Since the substreams 48 are shallow, each individual particle of tobacco in the substream 48 is substantially completely under the influence of the suction applied through the surface 40. The shallow depth of the substreams 48 allows all the air in the stream 46 to be handled readily by the suction across the surface 40 since the substeam 48 offers little or no resistance to the air flow. This latter result is in contrast to the structure disclosed in U.S. Pat. No. 3,030,965 wherein problems of air handling due to resistance of the filler rod on the conveyor band restricted the speed of operation and lead to the louvre modification of U.S. Pat. No. 3,019,793. The speed of operation of the apparatus of the present invention is not restricted in the manner of the prior art.

It will be observed that while, in the present invention, the same quantity of tobacco is formed into a filler rod as is the case using the prior art apparatus of U.S.

Pat. No. 3,030, 965,the quantity of tobacco in the present invention which is'forr'ned into the tiller rod, first, is evenly distributed across'thew idth of the stream 46 by way of the substreams 48 and, second, is distributed over a longer surface length due to the arcuate nature of the discs Therefore, the apparatus of the present invention 'is able to handle any desired volume of air in the passage 12 commensurate with the desired speed of formation of the filler rod. Hence, the necessity to use the louvre modification of U.S. Pat. No. 3,019,793, with its attendant operational problems, as discussed above, is avoided. The structure provided by the present invention, therefore, overcomes the air handling problems of the structure of'U.S. Pat. No. 3,030,965 while avoiding the operational problems of the louvre modification of U.S. Pat. No. 3,019,793.

Each substream 48, after formation thereof, is conveyed under the influence of the suction through the surface 40 to a point wherein the tobacco particles in the substream are moving adjacent to and in substantially ,the same direction as the conveyor band 22 or a partly-formed tobacco filler rod 50 already deposited on the conveyor band 22.

The discs 36 are rotated at substantially the same speed as the linear speed of the band 22 and hence the tobacco particles in the substream 48 have substantially the same speed as the band 22 and the partlyformed filler rod 50 on the band.

Suction is applied through the band 22 by means of the suction chamber 28 to hold the partly-formed filler rod 50 to the band 22.

When the tobacco particles in the substream 48 are moving adjacent to, substantially the same direction as and substantially the same speed as the band 22, the suction applied through the surface 40 is released by the action of the vacuum shoe 42 at which point the tobacco particles become under the influence of the suction applied through the band 22 and hence the particles of the substeam 48 are laid on the band 22 where .the right-most disc 36 (as viewed in FIG. 1) is considered or on the partly-formed rod 50 when the remaining discs are considered. The procedure occurs at each disc 36 and hence the filler rod is built up to its final thickness across the width of the passage 12 and a tobacco filler rod 52 is removed from the passage 12 in engagement with the band 22. The tobacco filler rod 52 is passed to further processing to form cigarettes in the well-known manner, as described fully in U.S. Pat. Nos. 3,019,793 and 3,030,965.

The substreams 48 therefore, in effect, are laid up on each other to form the filler rod 52, while the tobacco particles on the surface of the conveyor band 22 retain substantially the same juxtaposition as existed in the substreams 48. I

As illustrated in FIG. 3, as a result of the inclination of the line joining the axes 44 to the band 22 in accordance with the preferred embodiment, the substream 48 when positioned on the band 22 or on the partlyforrned rod 50 is substantially tangential to the surface 40 which assists in the gentle laying up. of the substream 48 to form the filler rod- 52 at the point of discharge. This arrangement and manner of operation is preferred although others may be used provided that, when the tobacco particles are positioned on the band 22 or on the partly-formed filler rod 50, they have substantially the same juxtaposition as existed in the substream 48.

Therefore, the substantially separated tobacco particles in the stream 46 are captured by the use of suction, conveyed under the influence of suction as a substream of tobacco to a discharge point where they are transferred intactly to the influence of the suction applied through the conveyor band 22. Since there is little or no relative speed between the band 22 and the tobacco particles in the substreams 48, the quantity of tobacco along the filler rod 52 is substantially uniform and, in this respect, the filler rod provided by the present invention is at least as good as that provided by the apparatus of US. Pat. No. 3,030,965.

Since the tobacco particles are completely under the influence of vacuum from their initial capture on the surfaces 40 to their positioning on the conveyor band 22, any air drawn by suction through the gap between the filler rod and the end wall 18 of the passage 12 has substantially no effect on the filler rod and hence the closure means of US. Pat. No. 3,091,244 may be omitted and its attendant problems avoided.

In addition, since the substreams 48 are thin, little or no classification of tobacco particles occurs and hence the filler rod 52 has a substantially uniform distribution of particle size in the cross-section thereof. This is in complete contrast to the filler rod produced by the rod forming apparatus of US. Pat. Nos. 3,030,965 and 3,019,793 wherein classification occurred. Therefore, the apparatus of the present invention produces a filler rod which is superior to that produced by the prior art machines and which does not have bad ends.

Further, since the filler rod 52 is formed by the apparatus of the present invention by the laying up of a succession of layers of tobacco across the width of the passage 12 and there is substantially no disturbance of the interface between the layers during the laying up, the filler rod 52 has excellent filling power which is superior to that of tobacco filler rods formed on the rodmaking apparatus of U.S. Pat. Nos. 3,030,965 and 3,019,793 leading .to a more economic tobacco use for the same cigarette hardness.

SUMMARY The filler rod-forming machine of the present invention therefore has several advantages over the prior art,

in that: v

1. The machine is capable of operating at any desired rod forming speed without encountering (a) the limitations of US. Pat. No. 3,030,965 caused by resistance of the partly-formed rod to air flow (b) the operational problems of the air flow separation technique of US. Pat. No. 3,019,793, and (c) the operational problems of the closure means of US. Pat. No. 3,091,244.

2. The machine forms a filler rod having a substantially uniform distribution of particle sizes in its crosssection, resulting in uniformly good cigarette ends and uniform burning rates, in contrast to filler rods produced on the rod-making machines of US. Pat. Nos. 3,030,965 and 3,019,793 which suffer from classification problems; 7

3. The machine forms a filler rod having a filling power superior to filler rods produced by the rod making machines of US. Pat. Nos. 3,030,965 and 3,019,793; and

4. The machine exhibits the above advantages without otherwise harming the uniformity of the quantity of tobacco in the length of the filler rod which is at least substantially as good as that of filler rods produced by the rod-making machines of US. Pat. Nos. 3,030,965 and 3,019,793.

Modifications are possible within the scope of the invention.

What we claim is:

1. A continuous tobacco filler rod-making apparatus comprising continuous opposed side and end walls defining an enclosed relatively thin and flat elongated passage having an inlet opening at a lower longitudinal extremity thereof, and having a tobacco gathering means closing the upper longitudinal extremity thereof,

means to feed tobacco in the form of substantially separated particles into the inlet opening,

said tobacco gathering means comprising a plurality of shallow cylindrical discs mounted to collect and convey a plurality of tobacco substreams and having their axes intersecting said opposed side walls approximately at right angles thereto,

each of said discs having substantially the same diameter and having a peripheral wall extending between said opposed side walls, each said peripheral wall including an air-permeable tobaccoimpermeable foraminous surface rotated about said axis at substantially the same speed in the same direction,

each of said discs being hollow and the interior thereof having a pressure that is less than atmospheric exerted through said foraminous surface to cause air to move continuously through said passage as a high velocity stream flowing from the inlet towards said gathering means and to convey said tobacco particles fed to the inlet in said air stream in said substantially separated form from the inlet towards said gathering means,

the portion of said foraminous surface of each of said discs intercepting the tobacco particles borne by said high velocity air stream constituting a narrow substream forming surface,

vacuum interrupting means positioned internally of each of said discs to prevent the application of said pressure over a selected arcuate length of each foraminous surface excluding substantially completely said substream forming surface to release tobacco particles of said substreams from said foraminous surface,

a narrow air-permeable and tobacco-impermeable foraminous conveyor arranged to move lengthwise adjacent said discs outside said passage to receive the tobacco particles of said plurality of tobacco substreams from said gathering means when said particles are released to form on said conveyor a filler rod, and

means to hold tobacco to said conveyor, said latter means including a suction device arranged to draw air through said conveyor to exert pressure on tobacco on said conveyor to hold the tobacco against the conveyor,

said vacuum interrupting means being positioned relative to each said foraminous surface to extend over said selected arcuate length thereof from approximately the point of closest approach of said surface to said conveyor, to release the tobacco particles of said substreams at said approximate point of nearest approach,

said conveyor being substantially flat and a straight line joining said axes being inclined with respect to said conveyor such that the substreams received tuting said foraminous surface and the remainder of said plurality of discs is provided with a substantially circumferentiallycontinuous foraminous surface in the peripheral wall thereof.

4. The apparatus of claim 1 wherein said vacuum interrupting means extends through of the arcuate length of said foraminous surface.

Claims (4)

1. A continuous tobacco filler rod-making apparatus comprising continuous opposed side and end walls defining an enclosed relatively thin and flat elongated passage having an inlet opening at a lower longitudinal extremity thereof, and having a tobacco gathering means closing the upper longitudinal extremity thereof, means to feed tobacco in the form of substantially separated particles into the inlet opening, said tobacco gathering means comprising a plurality of shallow cylindrical discs mounted to collect and convey a plurality of tobacco substreams and having their axes intersecting said opposed side walls approximately at right angles thereto, each of said discs having substantially the same diameter and having a peripheral wall extending between said opposed side walls, each said peripheral wall including an air-permeable tobacco-impermeable foraminous surface rotated about said axis at substantially the same speed in the same direction, each of said discs being hollow and the interior thereof having a pressure that is less than atmospheric exerted through said foraminous surface to cause air to move continuously through said passage as a high velocity stream flowing from the inlet towards said gathering means and to convey said tobacco particles fed to the inlet in said air stream iN said substantially separated form from the inlet towards said gathering means, the portion of said foraminous surface of each of said discs intercepting the tobacco particles borne by said high velocity air stream constituting a narrow substream forming surface, vacuum interrupting means positioned internally of each of said discs to prevent the application of said pressure over a selected arcuate length of each foraminous surface excluding substantially completely said substream forming surface to release tobacco particles of said substreams from said foraminous surface, a narrow air-permeable and tobacco-impermeable foraminous conveyor arranged to move lengthwise adjacent said discs outside said passage to receive the tobacco particles of said plurality of tobacco substreams from said gathering means when said particles are released to form on said conveyor a filler rod, and means to hold tobacco to said conveyor, said latter means including a suction device arranged to draw air through said conveyor to exert pressure on tobacco on said conveyor to hold the tobacco against the conveyor, said vacuum interrupting means being positioned relative to each said foraminous surface to extend over said selected arcuate length thereof from approximately the point of closest approach of said surface to said conveyor, to release the tobacco particles of said substreams at said approximate point of nearest approach, said conveyor being substantially flat and a straight line joining said axes being inclined with respect to said conveyor such that the substreams received from each of said discs onto the conveyor is substantially tangential to said foraminous surface and to the under surface of the conveyor or the rod being formed thereon.

2. The apparatus of claim 1 wherein each of said foraminous surfaces is circumferentially continuous.

3. The apparatus of claim 1 wherein one of said plurality of discs is provided with a peripheral wall having arcuately spaced-apart air permeable portions constituting said foraminous surface and the remainder of said plurality of discs is provided with a substantially circumferentially continuous foraminous surface in the peripheral wall thereof.

4. The apparatus of claim 1 wherein said vacuum interrupting means extends through 90* of the arcuate length of said foraminous surface.

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