EP0208925B1

EP0208925B1 - Withdrawing and singling device for withdrawing rod-like articles from a supplying hopper

Info

Publication number: EP0208925B1
Application number: EP86108107A
Authority: EP
Inventors: Gian Luigi Gherardi
Original assignee: SASIB SpA
Current assignee: SASIB SpA
Priority date: 1985-07-05
Filing date: 1986-06-13
Publication date: 1989-05-24
Also published as: DE3663438D1; EP0208925A1; IT1186905B; IT8512535A0

Description

The object of the invention is a withdrawing and singling device for withdrawing rod-like articles, particularly filter plugs used in the manufacture of filter-tipped cigarettes, from a hopper supplying the said articles, and for singling the same, which device is provided with a fluted rotary drum, that preferably is a suction drum, which makes up at least part of the hopper bottom, and with a so-called repelling roller that in correspondence of the end, from which the said drum issues from the hopper, is arranged between the fixed wall of the hopper and the fluted rotary drum, and is rotated in the same direction as this drum, so as to push back any rod-like articles which are not held within the flutes in the drum, and as to prevent them from coming out of the hopper or from getting wedged between the hopper wall and the drum, the said repelling roller being so provided that it allows any group formed by two or more rod-like articles associated with a same flute in the drum, to pass thereunder, and a sensing means being provided which is responsive to a group of rod-like articles associated with a same flute in the drum, any time the said group passes under the repelling roller.
A device of this kind for withdrawing and singling the filter plugs used in the manufacture of filter-tipped cigarettes, is known from the document FR-A 2 300 512. In this device the shaft for the rotation of the repelling roller is supported in an elastically yieldable manner and particularly is mounted on a roller-carrying lever which is allowed to swing about a fixed pin, and is urged by a spring toward the fluted drum, thus assuming a position in which the repelling roller performs its normal function. When one or more filter plugs come to be superposed, and possibly become stuck to one filter plug contained in a flute in the drum, this filter plug group passes under the repelling roller by elastically lifting same from the fluted drum, so that this group angularly moves in a related degree the lever-carrying roller, which actuates a microswitch. This promotes the disengagement of an electromagnetic coupling inserted in the transmission for driving at least some parts of the cigarette filter tip applying machine, or of the machine as a whole, so that either the said parts or the entire machine will be stopped. The elastically yieldable support for the repelling roller and the connection of said roller to a device for at least partly stopping the cigarette filter tip applying machine therefore prevents any damage that may be caused by a group of two or more filter plugs getting wedged under the repelling roller, but this support brings about the stopping of a part or of the entire cigarette filter tip applying machine. Such a stopping is continued for a certain period of time, and determines a proportionate output loss that is particularly important at the present high manufacturing speeds, and may be, for example, of 8.000 cigarettes per minute, and more than that. Moreover, in the instance of the machine having been entirely stopped, upon resuming the operation after a certain time, the cigarettes cannot be fed to the filter tip applying machine before a predetermined speed having been reached. Consequently, the cigarettes manufactured by the cigarette making machine during the related time interval must be discarded.
The prior art document DE-C 510 873 discloses a device for withdrawing and singling rod-like articles, particularly cigarettes, from a hopper supplying the said articles, which device is provided with a rotary drum, a repelling roller which rotates in the same direction as the drum so as to push back any rod-like articles which are not held within the drum flutes, and sensing means located downstream of the repelling roller and consisting of a swingable lever, which cooperates with one or more electric contacts, said sensing means being responsive to the softness of the rod-like articles, particularly to the incomplete filling of each cigarette located in a drum flute, and controlling removing means which are disposed downstream of the repelling roller and the sensing means and are adapted for removing from the fluted rotary drum the rod-like articles sensed by the sensing means. In this device, the shaft for the rotation of the repelling roller is mounted in a fixed position.
Therefore, a group of two or more superposed and stuck together rod-like articles, associated with a same drum flute, cannot pass beyond the repelling roller and may become undesirably wedged between the fluted rotary drum and the repelling roller. Such an inconvenience may occur also with two or more avalized, or anyhow distorted filter plugs which are associated with a same drum flute. Particularly, the forced passage of a group of filter plugs under the repelling roller with a stationary shaft for its rotation, besides the crushing and the breaking of these filter plugs, may deform the shaft for the rotation of the repelling roller and the components of the crushed filter plugs may damage any other members and be the cause of further troubles, thus impairing the regular operation of the machine and then reducing its output. In addition, in the device according to DE-C 510 873 the repelling roller is disposed outside of the hopper, i.e. is not arranged between the fixed wall of the hopper and the fluted rotary drum.
The documents US-A 1 393 642 and DE-C 506 802 disclose the combination of a hopper, a fluted rotary drum and a rotary repelling roller, which repelling roller is mounted in a fixed position and consists of a cylindrical brush. These devices are not provided with sensing means being responsive to a group of two or more rod-like articles associated with a same flute in the drum, any time such a group can pass under the repelling roller. The forced passage of a group of two or more rode-like articles, under the repelling roller of the device according to DE-C 506 802 is impossible and would cause the crushing and the breaking of these rod-like articles. In the device according to the US-A 1 393 642 the repelling roller is located inside the hopper, i.e. it is not arranged between the fixed wall of the hopper and the fluted rotary drum.
Prior art documents DE-C 497 881 and US-A 1 680 024 disclose devices in which means are provided for refilling empty flutes in a fluted rotary drum, said refilling means inserting one rod-like article into each empty flute and said means being located downstream of the repelling roller and of successive sensing means being responsive to each empty flute. The refilling means of the device known from US-A 1 680 024 include an auxiliary hopper for supplying rod-like articles to a downward channel containing a single row of rod-like articles and with its lower and terminating in correspondence of a stepwise-rotatable fluted transferring roller which is adapted for transferring one rod-like article at a time into one flute of the fluted drum. However, the repelling roller of the devices known from the documents DE-C 497 881 and US-A 1 680 024 is mounted in a fixed position and the forced passage of a group of two or more rod-like articles under this repelling roller is impossible without the crushing or the breaking of these rod-like articles. Besides, the sensing means are responsive only to an empty flute downstream of the repelling roller and not to a . group of two or more rod-like articles associated with a same flute in the drum and passing under the repelling roller. The invention aims to avoid the drawbacks of the known devices according to the preamble of the Claim 1 and solves this problem by the combination of the following features:

a) the repelling roller is mounted in a fixed position and consists of a cylindrical brush, which yields to such an extent as to allow the forced passage thereunder of a group of two or more rod-like articles associated with a same drum flute;
. ;-b)..%p tensing means is provided downstream of the repelling roller and consists of a swingable feeling lever cooperating with one or more electric contacts and movable by any group of two or more rod-like articles associated with a same drum flute;
c) the sensing means controls removing means which are disposed downstream of the repelling roller and the sensing means and generate compressed air jets blown through ports provided in the drum flutes, for expelling from the respective flute of the rotary drum and collecting in a reservoir any group of rod-like articles sensed by the sensing means;
d) downstream of the means for removing any groups of rod-like articles from the drum flutes, means are provided for refilling the flutes in the drum, which insert one rod-like article into each flute being in empty condition owing to a group of rod-like articles having been previously removed therefrom.

Thus, particularly in the instance of filter plugs for cigarettes, any time a group of two or more ovalized or stuck together filter plugs can pass under the repelling roller - whereby the breaking of the filter plugs and the pollution of any members of the cigarette filter tip applying machine be the fragments of the broken filter plugs, are avoided, the sensing means which is responsive to that group of filter plugs, will not stop the filter tip applying machine, or a part of this machine, but will promote the removal of the said cigarette group from the fluted rotary drum, with the aid of compressed air jets blown downstream of the sensing means through the drum ports.
The refilling means, provided downstream of the means for removing any groups of rod-like articles from the flutes in the drum, insert one rod-like article into each flute that is in empty condition, owing to a group of rod-like articles having been previously removed threrefrom. Thus, in the instance of filter plugs for cigarettes, it is avoided that in the cigarette filter tip applying machine there will be any pairs of cigarettes with no filter plug section interposed therebetween on account of one filter plug being absent from within the relative flute in the drum associated with the filter plug supplying hopper, whereby the rejection is avoided of the said cigarette pairs.
These and other features of the invention and the advantages arising therefrom will clearly appear in the following specification of one embodiment thereof, shown by way of a non-limiting example in the attached drawings, in which:

Figure 1 is an elevational view with parts in section showing a withdrawing and singling device according to the invention.
Figures 2, 3 and 4 are views in an enlarged scale of a detail of figure 1, showing the different successive steps of the passage of a group of rod-like articles under the repelling roller.
Figure 5 is an elevational view similar to figure 1, showing a modified embodiment of the device.

Referring to the figures, by numeral 1 it is designated a hopper supplying filter plugs B to a filter tip applying machine, for the manufacture of filter-tipped cigarettes. At least part of the bottom of said hopper 1 is made up by a drum 2 which is driven in rotation in the direction of arrow F1, and is peripherally provided with flutes 102. Each flute 102 in drum 2 can contain only one filter plug B, and is provided with ports (not shown) through which in known manner suction is applied at least in correspondence of the opening of hopper 1 and over a certain length downstream thereof. Besides these suction ports, the flutes 102 in drum 2 are also provided with air-blowing ports 202 for the purpose to be specified later.
In correspondence of the end from which the drum 2 comes out of hopper 1, a repelling roller 3 is interposed between the corresponding wall 4 of hopper 1 and the drum 2 and is rotated in the same direction as drum 2, and this roller pushes back the filter plugs B which are not held within the flutes 102 in drum 2, thus preventing them from coming out of hopper 1 or from wedging themselves between the hopper wall 4 and the said drum 2. The repelling roller 3 consists of a cylindrical brush which is so provided that it allows any group or cluster of two or more superposed, and may be stuck together filter plugs B1, which are associated with a same flute 102 in drum 2, to pass thereunder, as shown particularly in figure 2.
Preferably, the bristles covering the core 5 of the repelling brush roller 3 over a width which is substantially equal to the length of the filter plugs B, are inclined rearwardly with respect to the direction of rotation of said roller 3, and are assembled into equispaced groups or strips 6. Such a rearward inclination of the bristles of the repelling brush roller 3 has the purpose of increasing the compliance of said bristles, which is due to the pressure as applied thereon by the groups or clusters of filter plugs B1 that are inserted into, and pass between the drum 2 and the roller 3. The spaces 106 between the strips of bristles 6 have the purpose of promoting the receiving of the groups or clusters B1, by increasing the space available for them, and thus facilitating the issuing of said groups or clusters B1 from hopper 1.
Outwardly of the hopper 1 a feeling lever 7 is provided immediately downstream of the repelling roller 3, and this lever is swingably mounted about a fixed pin 107, and is biased into active position by a spring 207. The feeling lever 7 cooperates with a microswitch 8 which is connected to an electronic machine-controlling unit, which is known per se, and therefore it is not shown.
After having come out of hopper 1 and having passed under the repelling roller 3, a group or cluster of superposed filter plugs B1 associated with a flute 102 in drum 2, hits against the feeling lever 7 and angularly moves this lever from its normal position, shown in figures 1 and 2 and by dash-and-dot lines in figure 3, into its position shown by solid lines in the same figure 3. When in such a shifted position, the feeling lever 7 operates the microswitch 8 which signals to the control unit the issuing of that group of filter plugs B1 from hopper 1. Consequently, when the said flute 102 of drum 2 arrives at a position, downstream of the feeling lever 7, in which its air-blowing ports 202 come to coincide with the relative ports 9 provided in a fixed ring 10 fitted at the interior of the rotary drum 2, through these ports 9 which are set in communication with a manifold 21 connected to a compressed air source, a compressed air jet generated by the action of the control unit, is blown and expels the group of filter plugs B1 from the said flute 102, and removes that group of filter plugs from drum 2. The expelled filter plugs B1 are collected onto the bottom of a container 11 which preferably includes also the mechanical feeling unit with the lever 7 and the microswitch 8. The bottom of this container 11 is connected to the fluted rotary drum 2 through a spur-like part 12 with which terminates a guide 13 provided downstream of the spurlike part 12, around the single filter plugs B regularly received within the flutes 102 in drum 2, as it appears in figures 1 and 4.
When the filter plugs B1 associated with a same flute 102 in drum 2 are in a stuck together condition, for example owing to traces of glue being present on the plugs B1 and being yet not fully dried, the air jet blown through the air-blowing ports 202 directly acts upon that filter plug B1 in the group of filter plugs B1, which is received in the respective flute 102 of drum 2, and integrally ejects the group or cluster of filter plugs B1 from drum 2 in a substantially radial direction. Whereas, when the group of filter plugs 81 associated with a same flute 102 in drum 2 consists of filter plugs 81 that are not in a stuck together condition, and, for example, it consists of at least one distorted or ovalized plug lying upon a filter plug regularly received in the flute, as shown in the figures 2 and 3, it may happen that the air jet blown through the air blowing ports 202 in the flute will exert a less efficient action on the distorted filter plug or plugs B1 lying upon the filter plug contained in the flute, i.e., it will not succeed in projecting the said distorted filter plug or plugs sufficiently far away for causing them to fall directly into the plug-collecting container 11, contrary to what shown in figure 4. In this instance, the filter plug or plugs B1 which are not projected sufficiently far away by the air jet, will roll or hop on the fluted drum 2, also owing to the rotating drum driving them along, and will be lifted up from drum 2 and caused to fall into the container 11 by the terminalspur-like part 12 of guide 13, without upsetting in the least the other filter plugs B firmly held by suction within the respective flutes 102 in drum 2.
In order to better guarantee the removal of a group of stuck together or separate fjlter plugs B1 from the respective flute 102 in drum 2, the filter plug-ejecting air jet can be blown also through a flute located upstream and/or downstream of the flute with which there is associated the group or cluster of filter plugs B1 sensed by the feeling lever 7.
In the embodiment according to figures 1 to 4, the flutes 102 in drum 2 which owing to the ejection of the groups of filter plugs B1 are in empty condition, are no more filled, but are left empty, thus accepting to reject in the successive filter tip applying machine a few cigarette pairs having no filter plug interposed therebetween. In the shown embodiment, the filter plugs B, B1 are actually six times long as a simple filter plug, i.e., as the filter tip of a finished cigarette. On the same fluted rotary drum 2 each filter plug B is divided by two circular rotary blades 14, 15 into three filter plug sections being twice as long as a simple filter plug. Each one of these three filter plug sections is set between two co-axial cigarettes, is fixed thereto, and is then cut in the middle, so as to give rise to two filter-tipped cigarettes. Consequently, for each empty flute 102 in drum 2 three consecutive pairs of cigarettes must be discarded from the drum for assembling the cigarettes and their filter tips, since these three cigarette pairs will be without the interposed twofold long filter plug section. The rejection of these cigarettes is automatically promoted by the control unit, with the aid of its memory.
According to the invention, the above disclosed rejection of cigarettes can be avoided with the embodiment shown in figure 5. In this embodiment, the flutes 102 in the fluted rotary drum 2 from which the groups or clusters of filter plugs B1 are expelled, are soon afterwards refilled upstream of the rotary blades 14, 15, by inserting into each one of them a filter plug B2.
These filter plugs B2 are taken from an auxiliary hopper 16 for supplying the same, which may be also constituted by a part of the main filter plug supplying hopper, and from which there extends a downward channel 19 which is adapted for containing preferably only one row of filter plugs B2. At the connection between the auxiliary hopper 16 and the downward channel 19 there are provided two facing- ly arranged rollers 17, 18 rotating in the same direction; of these rollers, the roller 17 that preferably is a suction roller, drives the filter plugs B2 from the hopper 16 toward the channel 19, and promotes their descent along this channel 19, while the opposite roller 18 has the function of repelling roller. At the lower end of the downward channel 19 there is provided a fluted roller 20 for refilling the flutes 102 of drum 2, and which is stepwise rotated by a motor (not shown) which in turn is set in operation by the control unit. At the moment in which an empty flute 102 of drum 2 arrives at the refilling fluted roller 20, or short before that moment, the refilling fluted roller is rotated by one step, and transfers one filter plug B2 into the said empty flute 102 of drum 2. At the same time, another filter plug B2 goes from the downward channel 19 into the underlying flute in the refilling roller 20.
Of course, the invention is not limited to the just described and shown embodiments, but the same may be widely changed and modified, the more so in construction. More particularly, there may be changed the sensing means which is responsive to the groups or clusters of filter plugs B1 passing under the repelling roller 3, which cooperates with the fluted drum 2. Thus, for example, instead of the mechanical sensing means consisting of lever 7, an op- to-electric sensor, or a sensor of any other type, may be used. Both the means for removing the groups or clusters of filter plugs B1 from the fluted drum 2, and the means possibly provided for refilling the emptied flutes of drum 2 with only one filter plug, may be widely modified.

Claims

1. A withdrawing and singling device for withdrawing rod-like articles (B), particularly filter plugs used in the manufacture of filter-tipped cigarettes, from a hopper (1) supplying the said articles, and for singling the same, which device is provided with a fluted rotary drum (2), that preferably is a suction drum, which makes up at least part of the hopper bottom, and with a so-called repelling roller (3) that in correspondence of the end, from which the said drum (2) issues from the hopper (1), is arranged between the fixed wall (4) of the hopper (1) and the fluted rotary drum (2), and is rotated in the same direction (F2) as the drum (2), so as to push back any rod-like articles (B) which are not held within the drum flutes (102), and as to prevent them from coming out of the hopper (1) or from getting wedged between the hopper wall (4) and the drum (2), the said repelling roller (3) being so provided that it allows any group formed by two or more rod-like articles (Bi) associated with a same flute (102) in the drum (2), to pass thereunder, a sensing means (7) being provided which is responsive to a group of two or more rod-like articles (B1) associated with a same flute (102) in the drum (2), any time such a group passes under the repelling roller (3), characterized by the combination of the following features:

a) the repelling roller (3) is mounted in a fixed position and consists of a cylindrical brush, which yields to such an extent as to allow the forced passage thereunder of a group of two or more rod-like articles (B1) associated with a same drum flute (102);

b) the sensing means (7) is provided downstream of the repelling roller (3) and consists of a swingable feeling lever (7) cooperating with one or more electric contacts (8) and movable by any group of two or more rod-like articles (B1) associated with a same drum flute (102);

c) the sensing means (7) controls removing means (21, 9) which are disposed downstream of the repelling roller (3) and the sensing means (7) and generate compressed air jets blown through ports (202) provided in the drum flutes (102), for expelling from the respective flute (102) of the rotary drum (2) and collecting in a reservoir (11) any group of two or more rod-like articles (B1) sensed by the sensing means (7);

d) downstream of the means (9, 21) removing any groups of rod-like articles (B1) from the drum flutes (102), means (16, 17, 18, 19, 20) are provided for refilling the flutes (102) in the drum (2), which insert one rod-like article (B2) into each flute (102) being in empty condition owing to a group of rod-like articles (B1) having been previously removed therefrom.

2. The device according to Claim 1, characterized in that the bristles (6) of the brush forming the repelling roller (3) are inclined rearwardly with respect to the direction of rotation (F2) of said roller (3).

3. The device according to Claim 1 or 2, characterized in that the bristles (6) of the brush forming the repelling roller (3) are collected into angularly equispaced strips.

4. The device according to Claim 1, characterized in that the bottom of the reservoir (11) for collecting the rod-like articles (B1) expelled from the flutes (102) in the drum (2), is connected to at least one fixed spur-like part (12), which is adapted for lifting from the drum (2) and for conveying to the reservoir (11) the rod-like articles (B1) having been expelled from the drum flutes (102), but still rolling thereon.

5. The device according to Claim 1, characterized in that the refilling means consist of an auxiliary hopper (16) for supplying rod-like articles (B2) to a downward channel (19) containing one single row of rod-like articles (B2), and with its lower end terminating in correspondence of a stepwise rotatable, fluted transferring roller (20) which is adapted for transferring one rod-like article (B2) at a time into one flute (102) of the fluted drum (2).