US2752922A - Apparatus for feeding cut tobacco - Google Patents

Description

y 3, 1956 D. w. MOLINS APPARATUS FOR FEEDING CUT TOBACCO Filed March 6, 1955 nited States atentfififice 2,752,922 Patented July 3, 1956 This invention concerns improvements in or relating to apparatus for feeding cut tobacco. it

In tobaccofeeding apparatus (such as ina cigarettemaking machine) tobacco is often carried by an endless toothed conveyor such as a carded conveyorroller, and picked from the latter and showered,for example on to a further conveyor or into the trough of the cigarette making machine. To enable the tobacco to be evenly showered, it is desirable to form as far as practicable an even layer (or carpet as it is sometimes called) of tobacco on the surface of the toothed conveyor. Ini

tially, however, tobacco is often somewhat irregularly distributed over the surface of the toothed conveyor, so that some parts of that surface may contain too little tobacco or even none at all. It is therefore usual to employ some means to effect a redistribution of the tobacco on the toothed conveyor and also to attempt to pack the tobacco evenly into the conveyor teeth and to fill up any bare or sparsely filled areas that may exist. For these purposes it is often customary to supply more tobacco to the conveyor than is re uired and then to remove or separate thesurplus, for example by a refuser device such as a cardedhbrhshing roller. Usually the surplus tobacco so removed is allowed to build up in front of the refuser, and the toothed conveyor can thus take extra tobacco, where required,,from this accumula:

tion of refused tobacco.

In U. S. Letters Patent No. 2,326,793, granted August 17, 1943, to Molins et 211., there is disclosed aseparating device for separating surplus tobacco from the conveyor, the device having what is described as an uneven edge opposed to the direction of movement of the conveyor and adjacent the teeth of the conveyor, which edge is reciprocated transversely to the direction of movement of the conveyor. This lateral reciprocation of the uneven edge is for the purpose of assisting inseparating surplus tobacco from the tobacco between the conveyor teeth, and also of causing a more even distribution of the tobacco by brushing surplus tobacco sideways s o as to fill the conveyor teeth at portions. which might have a shortage of tobacco. 'Surplus tobacco not so redistributed passes over the edge and can be deflected away from the conveyor.

According to the present invention there is provided in tobacco-feeding apparatus means for removing surplus tobacco from tobacco carried by a toothed conveyor (e. g. a carded roller) comprising a plurality of. blunt fingers (e. g. of rounded cross-section) arranged side side across the conveyor adjacent the latter, and having blunt (e. g. rounded) free ends which are directed against and project into the oncoming tobacco on the conveyor, the said'fingers being spacedapart and arranged to move sideways across the conveyor. By the use of blunt fingers (which are preferably of rounded cross-section with rounded free ends), there are no edges or poi nts such as could cut the tobacco, which latter is able to pass more freely around the ends ands ides the lateral lymoving fingers than wouldbe'possible if there were vides a any edges such as would cut the tobacco, and this arrangement with the blunt fingers gives the tobacco a chance to be separated with less breakage during the removal of surplus tobacco than would be the case where the separation is effected by an uneven edge such as is shown in U. S. Patent No. 2,326,793. In addition, the fingers also act, by their sideways movement, to spread tobacco on the toothed conveyor.

in. the construction shown and described in the complete specification of U. S. Patent No. 2,326,793 it will bescen that the separating blade element 6 executes approximately one-third of a complete reciprocatory stroke during the period that a given point on the toothed conveyor 4 travels from the tip of a tooth to the base of a tooth. Accordingly, with such a construction, not a great deal of lateral spreading can be imparted to the tobacco before it reaches the base of a tooth. Furthermore, owing to their flat broad tips, the fronts of the teeth present edges to the advancing tobacco and as stated form part of an uneven tobacco-engaging edge. Thus owing to the relation between the forward speed of the conveyor and the speed of reciprocation of the saw blade, all thetobacco being fed forwardly is brought up against an edge by which separation must of necessity occur.

The present invention, on the other hand, which proconstruction which deals with the separation of surplus tobacco from the conveyor in a different manner, comprises, in tobacco-feeding apparatus, means for removing surplus tobacco from tobacco carried by a toothed conveyor (e. g. a carded roller) comprising a plurality of blunt fingers (e. g. of rounded cross-section) spaced apart side by side across the conveyor adjacent the latter, and having blunt (e. g. rounded) free ends which are directed against and project into theoncoming tobacco and are arranged to be reciprocated across the toothed conveyor, wherein the length of the fingers, the distance they are moved in each direction, and their speed, are so related to the speed of the toothed conveyor that the fingers execute at least a complete cycle of reciprocatory movement during the time taken by any given point on the conveyor to move a distance equal to the length of a finger, and wherein during said time at least one finger (e. g. four fingers) passes completely over such point in each direction of reciprocatory movement.

By this arrangement any tobacco meeting the ends of the blunt fingers is operated on by the fingers which are reciprocating and which therefore move sideways through the mass of tobacco whilst the latter is moving lengthwise of the fingers. In this way the fingers are given the opportunity of causing a drawing-out of strands in the mass of tobacco by their reciprocatory movement, and they have the opportunity moreover of spreading tobacco on the surface of the conveyor where, before meeting the fingers, the tobacco was not uniformly distributed. For instance, some portions of the conveyor may have too little tobacco on them whereas adjoining portions may have too much. Owing to the reciprocatory moveent of the fingers and to their length and to the abence of cutting edges on them, the fingers are able to carry some of the excess tobacco sideways which can be picked up by the teeth of the conveyor at places where it may be too little filled. The length of the blunt fingers relative to the speed of the conveyor is important toensure that at least one full reciprocatory movement is eiiected by the fingers during the time that any portion of the conveyor is passing beneath them.

Thus it will be seen that the fingers provide passageways alon g which the tobacco can travel between them, the fingers operating on the tobacco so moving .in such a way as to spread the tobacco laterally thereby helping to lay strandsinto the teeth of the conveyor and at the same time helping to separate surplus tobacco from the surface ofthe conveyor. spreading is effected in a desirable manner and at least a considerable portion of the spreading and separating is thus r'iec'essarilycompleted, before the tobacco-has any opportunity of coming up against an edge which would have the effect of cutting it.

A rotatable member may be arranged to engage surplus tobacco which passes over the fingers and to rotate in a-dire'ction such as to tend to move tobacco so engaged in a direction opposed to the direction of movement of the conveyor past the fingers. The rotatable member may consist of a roller with a roughened (e. g. knurled) surface.

There may be p'rovided a pressing element arranged to press against tobacco on the toothed conveyor, before such tebaceo reaches the said fingers, and having a surface opposed to the said rotatable member and adapted to guidesurplus tobacco moved by the said rotatable member so that such tobacco can pass between said surface and said rotatable member in a direction away from the toothed conveyor.

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

Figure l is a section through tobacco feeding apparatus including apparatus according to the invention;

Figure 2 is 'an enlarged view of a part of the apparatus showi'iin Figure 1;

Figure 3 is a plan view of Figure 2 taken in the direction of the arrow A;

Figures 4 and 5 are sections on the lines IV-IV and VV, respectively, of Figure 3, on an enlarged scale; and

Figures 6, 7 and 8 are sectional views similar to Figure 4 and showing modifications.

The tobacco feeding apparatus illustrated comprises a hopper 1 for tobacco, at the bottom of which is a conveyor 2'which moves in the direction shown by the arrow and operates to feed the mass of cut tobacco forwardly against the surface of a carded conveyor roller 3 rotating in the direction shown by the arrow. The teeth of the carding onthe conveyor roller are forwardly inclined considered the direction of movement of the roller surface, and so 'pick up tobacco from the hopper and carry it forwardly as a layer. The carded roller usually extracts more tobacco from the hopper than is required.

Above the conveyor roller there is provided a device for separating surplus tobacco from the quantity which it is desired should be carried forward by the conveyor roller 3, and also for assisting in the even distribution of tobacco inure c'a'rding of the roller.

This device comprises a comb-like member extending across-the conveyor roller 3 and having a large number of-fingers or finger like members 5 arranged side by side and located as -'clos'e as is practicable to the tips of the teeth of the carding on the conveyor roller 3. The free ends of the fingers 5 are directed against the tobacco carried towa-rds them by the roller 3, so that they'project into the oncoming tobacco and extend lengthwise and in line with the tobacco layer, with their free ends directly opposed to oncoming tobacco moving toward them, thereby penetrating between entangled strands of oncoming tob-a'cco. v

The'fingers 5 are formed on a bar or common support 7 which extends across the carded roller 3 and is fixed on a support 'm'ember'27. The support member 27 (is arranged to-be "reciprocated across the roller 3, so that the fingers '5 move sideways to and fro across the path of the oncoming'tobacco, thus pulling some of the entangledstrands sideways in both directions while they are moving along the length of the fingers. At the same time the fingers smooth, and spread sideways, tobacco passing beneath them. The fingers are reciprocated so as to move a distance of 40 mm. in'each direction; thuseach'firrger has a'tdt'al lateral movement of 40*m1nQin each direction.

Thus the action of separating and Bevelled surfaces 20 on the bar 7 connect the rear ends of the fingersiand' have edges 21 adjacent th'e'teeth' of the roller 3. The fingers 5, in the example illustrated, are each one inch long measured from their tips to the edge 21, and A3 wide. The side faces of adjacent fingers are spaced apart a distance. of Thus the fingers themselves are pitched or spaced apart laterally from one another by a distancewhich is less than a third of the distanceoflateral movement-of the fingers in each direction.v

The speed at which the fingers:arereciprocated, in re lation to the speed of the carded roller 3, is such that each finger executes a complete stroke in each" direction, and in addition three-fifthsofastroke in one direction (or in other words about one and a third complete cycles of reciprocation) during "the time taken by any given point on the conveyor 3 to move a distance of one inch forwardlythat is, a distance equal to the length of a finger 5. Thus several fingers passsideways in both directions over any given portion of tobacco which is moving beneath them. These movements of the fingers 5' in relation to the movement of the roller. 3 are diagrammatically represented-in Figure 3 by arrows. Thus the arrow A-B represents to scale the direction and extent of reciprocatory lateral movement of the fingers 5 during the time in which a point on the conveyor roller 3 moves forwardly a distance equal to the length of a finger 5, which distance is represented to scale by the arrow CD.

The reciprocation of the support member 27 across the carded roller 3 is effected by any suitable and convenient mechanism such for example as the mechanism shown and described infthe complete specification and drawings of United States Patent No. 2,326,793, issued August 17, 1943, for reciprocating the blade .6 in the construction disclosed in that specification and reference is made to that specification for such mechanism. In that construction, as shown in the drawings of that specification, the blade 6 is connected by clamps 103 to flexible straps 104 fixed at '38'to curved faces. of double-armed levers 39 which are rocked. by a lever -46 pivoted to an eccentric rod 47 which isfixed-to an eccentric strap 48 mounted on an eccentric 49. Figure 3 'of the accompanying drawing shows diagrammatically such straps 104 connected to the bar 7 by clamps 103.

The fingers 5 themselves are blunt, both at their free ends and along their. lengths. That is to say, they have no sharp pointsor corners at their free ends, and no sharp edges along their lengths, such 'as would have the effect of cutting tobacco. In the specific example described and illustrated, the fingers are rounded cross-section and have rounded ends; The word blunt, however, when used herein in relation to the fingers, does not necessarily mean that the fingers must be rounded as shown in Figure 4 of the accompanying drawings. For example, as illustratedfin Figure 6, they could have flat surfaces such as 50"joined by curved surfaces such as 51. The word blunt however, doesnreanthat there are no sharp edges of such a nature aswould cut the tobacco.

Thus the fingers shown in Figures 2 and 3 vary in crosssectional shape from approximately circular near the free ends as shown in Figure 4 to approximately elliptical in the region "of the' bevelled surfaces 20 as shown in Figure 5; but they could if desired be of approximately rectangular cross-'sectionwith the corners of the rectangle rounded orcurved, Figure 7 shows. an example of such a crosssection. Further, they could have fiat surfaces meeting at an edgefas shown in Fig. "8, ,provided. that .the angle between adjacent faces is sufliciently obtuse that the edge is not sharp enoughjto cut theztobacco, or when passing over the conveyorteeth to co-operate with thelatterto-cut the tobacco.

Abovethe bar 7 is located removal meanscomprising aroller 9 which has a roughened, .e. g. knurled cylindrical surface the knurling .heing-.-shown on .an exaggerated scale in Figures andTZ) '.an'd.whichjis arranged for Iotation in the direction shown by the arrow so that its knurled surface moves over the bar 7 in a direction opposed to the general direction of feed of the tobacco. The purpose of this roller is to sweep back and effect a return movement of strands of tobacco which pass above the fingers 5. Such tobacco swept back by the roller 9 is returned to the carded roller 3.

A cleaning blade 10 is fixed on the support member 27 so as to be reciprocated with the latter so that its edge scrapes the roller surface to clean it.

A presser-element 11 of ovate section, as shown in Figure l, and mounted on arms 12 pivoted at 13, is arranged to ride on the tobacco carried by the conveyorroller 3 to apply pressure to the tobacco so as to tend to press it into the teeth of the carding on the roller 3 and also to compress the tobacco somewhat before the latter reaches the fingers 5, in order to enable the latter to operate satisfactory on the tobacco. It will be appreciated that in order to obtain good results, the tobacco should be fairly compact when reaching the fingers. The arrangement shown provides such conditions. The presser-element 11 also co-operates with the knurled roller 9 by presenting a curved guide surface, opposed to and spaced from the surface of the roller 9, to the surplus tobacco which is brushed back by the roller 9 to guide the said tobacco upwardly over the top of the element 11, and the surfaces of the roller 9 and presser element 11 define between them a passage 111 for tobacco engaged by the roller. Thus the surplus tobacco which is separated from the surface of the conveyor and passes above the reciprocating fingers 5 is urged upwardly by the knurled roller 9 between the latter and the presser-element 11 through the passage 111 so as to enable the tobacco to pass over and round the presser-element so that it eventually can return to the roller 3 (subject to any excess tobacco being taken away by a roller 14 mentioned later), and again move forwardly towards the fingers 5. In this way a circulatory movement, in a generally clockwise direction as viewed in Figure l, is imparted to the surplus tobacco, which is thus kept moving continuously, and there is therefore little tendency for the surplus tobacco to become tangled or twisted in such a way as to make it difiicult for it to be taken in the teeth of the carded roller 3.

A roller 14, with rearwardly inclined pins 15, and arranged to rotate in the direction of the arrow, is also provided for the purpose of trimming or raking the tobacco carried on the conveyor 3. A vertically reciprocable tamper 16 is suspended from the end of a lever 17 by a chain 18, the lever 17 being mounted on a shaft 19 which is operated automatically to rock the lever 17.

A raking device is arranged to rake tobacco backwardly when there may be too much tobacco piled up in the region of the said device. This raking device comprises a number of rakes 150 and 151 fixed on a shaft which extends across the hopper and is fixed on links 152 and pivoted on a crank 153, which latter is mounted on a shaft 154 arranged to rotate in the direction shown by the arrow. The links 152 are pivoted on swinging arms 155. By means of this arrangement the ends of the rakes are caused to move in closed paths as indicated by the chain-dotted lines in Figure 1.

The tobacco after passing the member 7 is picked or fed in any suitable manner.

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

1. In tobacco feeding apparatus having a toothed conveyor to carry tobacco, means to remove surplus tobacco from tobacco on said conveyor, comprising a plurality of thick fingers of rounded cross section and having rounded free ends, means supporting said fingers spaced laterally apart side by side across and adjacent the said conveyor so as to point in a direction opposed to the direction of movement of said conveyor adjacent said fingers and means to reciprocate said fingers laterally across the said conveyor to tease out tobacco on said conveyor, wherein the said fingers are pitched laterally apart one from another by a distance not greater than one-third the distance of lateral movement of said fingers across the conveyor in each direction of reciprocation.

2. In tobacco feeding apparatus having a toothed conveyor to carry tobacco, means to remove surplus tobacco from said conveyor, comprising a plurality of laterally spaced thick blunt fingers having free ends, means supporting said fingers side by side across and adjacent said conveyor so as to point in a direction opposed to the direction of movement of said conveyor adjacent said fingers, and means imparting to said fingers reciprocatory lateral movement across said conveyor providing at least a complete cycle of reciprocation during movement of any point on said conveyor a distance equal to the length of a finger, the lateral spacing of each finger from the next being less than the lateral displacement of the fingers in each direction of reciprocation across said conveyor.

3. Apparatus as claimed in claim 2 and including removal means engaging and removing tobacco passing over said fingers, said removal means comprising a rotatable member between which and the said conveyor the said fingers extend, and having a portion adjacent to and movable past the supported ends of said fingers in a direction opposed to the direction of movement of said conveyor, said portion of said member being engageable with tobacco passing above said fingers to effect a return movement of such tobacco over the fingers, and means rotating said member.

4. Apparatus as claimed in claim 3 in which the rotatable member is a roller having a roughened peripheral portion adjacent said fingers, said apparatus including a pressing element arranged to press against tobacco on a part of the toothed conveyor approaching the free ends of said fingers, and said pressing element having a surface opposed to and spaced from said peripheral portion of said roller to define therebetween a passage for tobacco engaged by the peripheral portion of said roller.

5. Apparatus for removing surplus tobacco from a layer of cut tobacco, comprising means for moving the layer of tobacco forwardly, spaced fingerlike members mounted to project into the oncoming tobacco so as to extend lengthwise along and in line with said layer so that the free ends of said members are directly opposed to oncoming tobacco moving toward them and thereby penetrate between entangled strands of said oncoming tobacco, means to reciprocate said members sideways through and across said layer so as to pull some of the entangled strands sideways in both directions while they are moving along the length of said members, thereby to disentangle and separate said strands from other strands without cutting them, while smoothing, and spreading sideways, tobacco passing beneath the said members, the rate of reciprocation of said fingerlike members being such that several of them pass in both directions over any given portion of tobacco which is moving beneath them, and means to engage strands of tobacco which are passing above the said members and to brush such strands rearwardly to return the same to the oncoming layer of tobacco.

References Cited in the file of this patent UNITED STATES PATENTS 1,859,965 Gwinn May 24, 1932 2,066,338 Dalton Jan. 5, 1937 2,253,362 Broekhuysen Aug. 19, 1941 2,326,793 Molins Aug. 17, 1943 2,388,772 Thompson Nov. 13, 1945

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