US3443688A - Machines for manipulating cut tobacco - Google Patents

Description

May 13, 1969 D. w. MoLlNs v 3,443,688

MACHINES FOR MANIPULATING CUT TOBACCO Filed Aug. 19, 1966 sheet of 4 May 13, 1969 D. w. MoLlNs MACHINES FOR MANIPULATING CUT TOBACCO Sheet 3 o'f 4 Filed Aug. 19, 1966 MACHINES FOR MANIPULA'I-ING CUT TOBACCO Filed Aug. 19, 196e sheet 3 of 4 I 17%, @Jihad wenn.'

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United States Patent O 3,443,688 MACHINES FOR MANIPULATING CUT TOBACCO Desmond Walter Molins, Deptford, London, England, as-

sgnor to The Molins Organisation Limited, London, England, a corporation of Great Britain Continuation-in-part of application Ser. No. 292,604, July 3, 1963. This application Aug. 19, 1966, Ser. No. 573,517 Claims priority, application Great Britain, `Iuly 18, 1962, 27,576/ 62 Int. Cl. B07b 4/02 U.S. Cl. 209-12 5 Claims ABSTRACT OF THE DISCLOSURE A separator for cut tobacco has an elutriating passage for a primary separation of light from heavy particles. At the lower end of the passage a roller having small recesses in its periphery receives the heavies fraction for secondary separation thereof. Small usable tobacco particles enter the recesses and the larger unusable tobacco remains on the surface of the roller. The small particles from said recesses is pneumatically combined with the primary lights fraction.

This application is a continuation-in-part of my copending application, Ser. No. 292,604, filed Iuly 3, 1963, and now abandoned.

This invention concerns improvements in machines for manipulating cut tobacco, such for instance as continuous rod cigarette-making machines, and is more particularly concerned with apparatus for separating stem and large fragments from cut tobacco.

`Cut tobacco is sometimes made by cutting Whole tobacco leaves so that the resulting tobacco is a mixture of cut lamina and cut stem. This mixture is not usually considered suitable for incorporation into cigarettes or other tobacco articles since some of the stem pieces are too large. In cigarettes, for example, large pieces of stem usually do not burn and may pierce the enveloping cigarette paper. Such pieces will be referred to hereinafter aS unusable stem whereas pieces suitable for incorporation will be referred to as usable stern. Any other large undesirable fragments present in the cut tobacco will together with the unusable stem be referred to as unusable material.

It is to be understood that the distinction between what is usable and what is not depends on the purpose to which the tobacco is to be put and on the preferences of a manufacturer. Reference to the size of tobacco particles and of parts of the apparatus used for effecting separation needs to be considered in this light. However, suitable average sizes in the case of cigarette tobacco may be stated by way of a guide.

The object throughout is to separate such portions of the tobacco as the manufacturing user considers undesirable in his product and to this end there is provided apparatus for separating cut tobacco containing unusable material into usable and unusable portions with the separation carried out in two stages, the apparatus of one stage comprising walls defining a substantially vertical passage, means to cause an air stream to ow up the 3,443,688 Patented May 13, 1969 "ice passage and means to feed tobacco into the passage, the air stream being such that usable tobacco only is entrained therein to be carried up the passage while the remaining tobacco falls through the air stream; and apparatus of the other stage comprising a compartment, means to feed tobacco to the compartment, a movable member forming the base of the compartment, recesses in the surface of said member into which only usable particles of tobacco can enter, means for continuously removing from the compartment unusable tobacco carried on the surface of the member and a receiver into which usable tobacco can fall from the recesses of the member.

A surface recessed as specified above could be a flat surface, for example a series of plates Acarried by a conveyor or the at surface itself of a conveyor, but for general convenience of manufacture and of operation a recessed roller or cylinder is to be preferred.

Apparatus in accordance with the invention will now be described by way of example with reference to the accompanying drawings in which:

FIGURE l is a section through part of a continuous rod cigarette-making machine showing a preferred cmbodiment of the invention,

FIGURE 2 is the same section as that of FIGURE 1 drawing to a smaller scale and including more apparatus than that shown in FIGURE 1,

FIGUR-E 3 is a section drawn to a larger scale of a fragment of a recessed cylinder shown in FIGURE l,

FIGURE 4 is an end view of FIGURE 3,

FIGURE 5 is a view, partly in section, of a driving device for the cylinder of FIGURE 3,

FIGURE `6 is a side elevation of FIGURE 5,

FIGURE 7 is a view similar to that of FIGURE 1 showing .another embodiment of the invention; and

FIGURE 8 is a view similar to those of FIGURES 1 and 7 showing a still :further embodiment.

Referring first to FIGURES 1 and 2, a carded drum 1, which is part of a hopper 2 of acontinuous rod cigarette-making machine, rotates in theA direction of arrow 3 and in so doing removes cut tobacco from the hopper 2, delivering it in the form of a carpet past a refuser drum 4 and combs 5 to a picker roller `6. Pins 7 on the periphery of the picker roller `6 strip the carpet of tobacco from the carded drum 1 and project it over the surface of a partly concave shaped plate l8 between which and serrations 9 of a winnower roller 10 the tobacco particles are directed. The roller 10 rotates in a clockwise direction as seen when looking at both FIGURES 1 and 2 and thus impels the tobacco to the left. The speed of the roller 10' can be varied so that any desired initial velocity can be irnparted to the particles.

Beyond the plate `3 is .a further plate 11 pierced by rows of holes 12 which are directed to a point above. The dotted lines between the holes 12 represent the next row which is staggered in relation to the row shown in the section of FIGURE 1. The holes of each row are directed to their own respective point above the plate 12, all these points being in a straight line perpendicular to the section plane.

Tobacco particles can travel up a substantially vertical passage 13 to form a filler on the underside of an air pervious conveyor (not shown in FIGURE 2) which separates the top of the passage 13 from a suction chamber 14, all as disclosed in U.S. Patent No. 3,030,965,

3 issued Apr. 24, 1962. The suction chamber 14, which communicates via piping with a 'fan 116, causes a main air stream to ow up the passage 13, this ow being augmented by air sucked by a further fan 17 via piping 18 and 19.

The main air stream iiowing up the passage 13 causes air to tlow through the holes 12. This air flow is transverse to the direction of movement of the impelled tobacco and is so regulated that it entrains light tobacco particles which are u'sable deecting them in a curved path around a rotating perforated cylinder 20 and into the passage 13. This deliection is asserted by a-ir passing into the centre of the cylinder 20 and then out on its other side into the end of the piping 18. The air through the cylinder 20 also removes dust and small fragments from the impelled tobacco, these being separated from the air in a separator 21 and being delivered by means of a duct 22, the fan 16 and yfurther piping 23 t-o dust collectors 24.

The main airstream carries a considerable part of the usable tobacco contained in the tobacco impelled by the roller 10 up the passage 13. However unusable tobacco is too heavy lto be deected and passes through the main air stream into a receptacle 25. Mixed with the unusable material, which consists mainly of large pieces of stem, are some smaller and usable pieces of stem as well as shreds of lamina both of which become entangled with and carried along by the unusable material.

The receptacle 25 is formed `by side plates 26 and 27 with a rotatable metal roller 28 a-s its bottom. The roller 28 has a serrated periphery formed by cutting 90 V- shaped grooves about 0.030" deep. The side plate 26 ends in a resilient member 29 which cooperates with the roller 28 to act as an air lock whilst allowing tobacco which has fallen into the bottom of the receptacle 25 to pass therebetween. Contact between the member 29 and the roller 28, which rotates as indicated by arrow 30, can be adjusted by means of a screw 311 and a spring 32.

The tobacco fed between the member 29 and the roller 28 enters a substantially vertical passage 33 above which is a curved 4passage 34. One wall 3S of the passage 33 is fixed to a bracket 36 which is joined by means of adjustable screws 37 to a plate 38 located on the main frame of the machine. A further locating screw 39 bears against the faceV of the bracket 36. By adjusting the screws 37 and 39 the position of the Wall 35 can be moved sufliciently to vary the cross-sectional area of the passage 33. Hinged to the top of the wall is an extension piece 40 which can be swung into any one of a series of desired positions by means of a quadrant bracket 41. A wall 42 opposite the wall 35 is fixed. The lower ends of the walls 35 and 42 are joined to perforated plates 43 and 44, respectively.

Due to the perforations in the plates 43 and 44 air can enter the bottom of the passage 33 and can only leave by means of the curved passage -34 whose upper end finishes in the vicinity of the lower end of the passage 13. Thus suction exerted in the chamber 14 causes a subsidiary air stream to ow up the passages 33 and 34 at the end of which this subsidiary air stream becomes part of the main air stream. The quantity of -air owing up the passage 33 can be varied by moving the extension piece 40 in relation to the lower end of wall 45 of the passage 34. This either closes or opens a gap and thus regulates the entry or otherwise of further air at this position. The velocity of the air up the passage 33 can be modied by changing the position of the wall 35 by means of the screws 37 and 39 as described hereinabove.`

The' tobacco discharged through the air lock formed by the member 29 and the roller 28 is impinged on by the rising subsidiary air stream which is regulated to entrain only usable tobacco. Usable tobacco is thus carried up the passages 33 and '34 after which it enters -into the main air stream where it joins the usable tobacco from the roller 10. The unusable materia-l together with so-me usable tobacco entwined or adhering thereto falls through the air 4stream onto the surface of a rotatable cylinder 46 which forms the bottom of the passage 33. 'Some of this tobacco will drop into small recesses 47 formed in the periphery of the cylinder 46, as more specifically described hereinafter, while pieces of unusable material too long or too large to lodge in the recesses 47 remain on the periphery. The cylinder 46 rotates in an anticlockwise direction as seen when looking at FIGURE l, thus removing both usable tobacco which is lodged in the recesses 47 and unusable material on the cylinders surface from the bottom of the passage 33 which in the region of the perforated plates 43 and 44 can be regarded as a compartment.

The unusable material passes through a gap 48 between the bottom of the plate 43 and the cylinder 46 and are removed from the cylinders surface by a brush 49 rotating in a clockwise direction, falling into a receptacle 50. At the bottom of the receptacle 50 is a duct S1 having its top half removed so that the particles of unusable material can pass from the receptacle 50 into the duct 51 in which they are removed from the lmachine by means of an airflow from a source not shown.

The usable material lodged in the recesses 47 is carried by the rotation of the cyclinder 46 past a retaining plate 52 into a receiver 53. The top of the receiver 53 becomes a rising passage 54 which emerges to the left (as seen when looking at FIGURE 1) of the plate 11. The bottom of the receiver 53 is open to atmosphere at 55 and thus a further subsidiary air stream rises through the receiver 53 and the passage 54 to join the main air stream the remaining air for which is made up of that emerging through the holes 12 and from the passage 34. This subsidiary air stream up the passage 54 has suicient velocity to entrain the remaining usable tobacco from the recesses 47. The air drawn through the holes 12 is supplied from a duct 56 which is fed from the fan 17 via a further duct S7 (see FIGURE 2). The duct l56 is subdivided to provide streams of air substantially as shown by the arrows in FIGURE 1 these streams being guided by separating members 58.

The cylinder 46 is constructed from a number of narrow discs 59, see FIGURES 3 and 4, mounted on a shaft and separated one from the other by thin circular plates 60. The circular plates 60 and the tips of the discs S9 form the periphery or surface of the cylinder 46 on which the unusable material rests.

It has been found advantageous to drive the cylinder 46 intermittently, the arrangements being shown in FIG- URES 5 and 6. The cylinder shafts 59a is tted with a sprag clutch 60a the driving member of which is provided With a lever 61. The lever 61 is oscillated by an eccentric rod 62 which is driven by an eccentric `(not shown) fixed on a rotatable shaft of the cigarette making machines. A grooved pulley 63 engaged by a brake shoe 64 drawn into engagement therewith by a spring 65 prevents overrun or backlash.

The operation of the apparatus will now be described.

The cut tobacco handled in the hopper 2 is a mixture of cut lamina and cut stem. It is stripped by the picker pins 7 from the carding of the drum 1 with the speed of the picker roller 6 being suiciently high at approximately 190041,50() r.p.m. to tear apart long strands of tobacco and to separate the stem and lamina portions. -Due to the presence and shape of the plate 8 all the stripped tobacco is directed between this plate and the winnower roller 10. By adjusting the speed of the roller 10 the tobacco can have imparted to it any desired amount of momentum. The action of the main air stream is selective `in carrying away only light usable tobacco up the passage 13 while stem and other unusable material continue their movement across the flow of the main air stream and into the receptacle 25.

The tobacco in the receptacle 25, comprising mostly of unusable material but with some usable tobacco intermingled with or clinging thereto, is discharged through the airlock formed by the member 29 and the roller 28. As stated above, there is a subsidiary air stream moving upwards in the passage 33. In this rising air stream the tobacco which has passed through the air-lock 29-28 is further separated with some of the light usable tobacco being carried by the subsidiary air stream to join the main air stream flowing up the passage 13. The remainder of the tobacco, mostly heavy unusable tobacco falls through the air stream onto the rotating cylinder 46. To regulate the degree of separation, the air velocity of the subsidiary air stream may be varied by altering the setting of the wall 35 and of the extension piece 40, both as described hereinbefore.

Of the tobacco falling onto the top of the cylinder 46 the usable small particles enter the recesses 47. Unusable material which is too big for such entry remains on the surface of the cylinder 46 supported on the plates 60 until the rotating brush 49 removes itv therefrom when it falls into the duct 51 by which it is removed from the apparatus. As the cylinder 46 rotates, the usable material in the recesses 47 is carried round, being held therein by the retaining plate 52. At the end of the plate 52 it falls away from the cylinder 46 into the receiver 53 from which it is removed by the lifting action of the further subsidiary air stream flowing up the passage 54. At the top of this passage the entrained particles of usable tobacco enter into the influence of the main air stream which carries them up the passage 13.

In this way the usable tobacco is segregated from the unusable material although it is possible that some of the former might circulate more than once through the separating apparatus.

FIGURE 7 resembles FIGURE l in many ways and represents a further embodiment of the invention. Like references refer to like parts and in the following description the differences only will be described.

The air lock comprises as before a roller 28 rotating in the direction of the arrow 30. In contact with the roller 28 is a rubber covered roller 66 rotating in the opposite direction. The rubber covering of the roller 66 is of Soft or spongy material and is readily deformable when tobacco passes between the two rollers which thus form an air lock to prevent air being sucked by the compartment 25 and thus interfering with the function of the passage 33.

The walls 35 and 42 of the passage 33 are provided with holes 67 and 68 respectively at their lower ends. The cylinder 46 is provided with V-shaped grooves 69 into which the usable tobacco can fall. The unusable material carried on the surface of the cylinder 46 is brushed into a rotating air lock 70 which discharges into the duct 51.

A further embodiment is shown in FIGURE 8 in which like references again refer to like parts. The air lock nOW comprising the rubber covered roller 66 and a cylinder 71 which resembles the cylinder 46 of FIGURE 7 in having its surface covered with V-shaped recesses 72. The usable small tobacco from the compartment 25 enters into and is retained in the recesses 72 to be delivered to the receptacle 53 from which they are removed as previously by the further subsidiary air stream iiowing up the passage 54. The remaining tobacco, mostly unusable material with a small amount of usable tobacco entwined or adhering thereto passes through the air lock into a passage 73 at the bottom of which is the air lock 70 and the duct 51.

A subsidiary air stream flows up the passage 73, the opposite walls 0f which, 74 and 75, are provided with inlet holes 76 and 77 respectively. The wall 74 is again adjustable and is provided with the hinged extension piece 40.

In this embodiment first stage separation is carried out by the cylinder 71 followed by second stage separation by the air stream flowing up the passage 73.

What I claim as my invention and desire to secure by Letters Patent is:

1. In a cigarette-making machine, means defining a substantially vertical passage, means to cause an airstream to flow towards and up said passage, means to project tobacco across said airstream whereby light tobacco is entrained and carried through said passage while the remainder of the tobacco falls, means defining a first compartment to receive said remainder, a separating cylinder forming the base of said compartment and having peripheral recesses separated by divisions narrower than said recesses, said recesses being of a size to accommodate only usable pieces of tobacco contained in said remainder, means defining a second compartment adjacent the first compartment and having an opening adjacent said cylinder to receive therefrom large unusable pieces of tobacco which rest on the divisions of said cylinder, a duct connecting one of said compartments with said passage, means to cause air to flow upwardly through said one compartment and said duct to entrain light elements of said remainder falling through said one compartment, a channel to receive usable pieces of tobacco from said recesses and directed towards said passage, and means to cause air to flow through said channel to entrain said usable pieces and project them towards said passage.

2. In a cigarette-making machine of the kind comprising a hopper to receive cut tobacco containing stem, means to cause an upward airstream and means for removing tobacco from the hopper and impelling it across the path of the upward airstream which carries away only usable tobacco to form a main airborne stream of usable cut tobacco while the remainder of the tobacco falls, a first receptacle to receive the remainder of the impelled tobacco; second airstream means for separating said remaining tobacco into light and heavier fractions and for conveying said light fraction to said upward airstream while said lheavier fraction falls; means for feeding the remaining tobacco from said receptacle to said second airstream means and for preventing airflow between said first receptacle and said second airstream means; further means for receiving and separating said heavier fraction into usable and unusuable portions comprising a roller having small recesses in its periphery separated from one another by thin divisions, said recesses being of such size that only usable tobacco may enter and be contained therein while unusable tobacco remains on the periphery supported by said divisions, means for rotating the roller whereby said usable tobacco in said recesses is carried around by the roller to a delivery position and means for removing unusable tobacco from the roller periphery at a position in advance of said delivery position; and means for conveying said usuable tobacco from said delivery position to said upward airstream.

3. A cigarette-making machine as claimed in claim 2 wherein said means for feeding the remaining tobacco from said receptacle to said second airstream means and for preventing airflow between said first receptacle and said second airstream means comprises a pair of feed rollers capable of rotating in opposite directions and in contact with each other, at least one of said rollers being of resilient material.

4. A cigarette-making machine as claimed in claim 2 wherein said means for feeding the remaining tobacco from said receptacle to said second airstream means and for preventing airflow between said first receptacle and said second airstream means comprises a rotatably mounted feed roller having a serrated periphery and a resilient scarpper member which cooperates with said roller.

5. In a cigarette-making machine of the kind comprising a hopper to receive cut tobac-co containing stem, means to cause an upward airstream and means for removing tobacco from the hopper and impelling it across the path of the upward airstream which carries away only usable tobacco to form a main airborne stream of usable cut tobacco, a first receptacle to receive the remainder of the impelled tobacco, second air stream means for separating tobacco into light and heavier fractions and conveying said light fraction to said upward airstream while said heavier fraction falls, means for feeding the remaining tobacco out of said receptacle and for separating said remaining tobacco into usable and unusable portions comprising a .pair of rollers capable of rotating in opposite directions and in Contact with each other, one of said rollers having small recesses in its periphery separated from one another by thin divisions, said recesses being of such size that only usable tobacco may enter and be contained therein while unusable tobacco remains on the periphery supported by said divisions, and means for rotating said one roller whereby said unusuable tobacco is conveyed to a position where it is separated into said light and heavier fractions and said light fraction is removed by said second airstream and said usable tobacco in said recesses is carried around by the roller to a delivery position, the other roller engaging the periphery of said recessed roller at a position in advance of said second airstrearn for preventing airow between said second airstream means and said lirst receptacle; and means for conveying said usable tobacco from said delivery position to said upward airstream.

References Cited FRANK W. LUTTER, Primary Examiner.

U.S. Cl. XR.

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