The present invention concerns a method and an apparatus for the recovery of tobacco from cigarettes with filter.

Cigarettes commonly consist of a paper cylinder enveloping and enclosing tobacco and/or other materials such as cloves and the like. To smoke a cigarette, users light one of its ends, then suck the air from the opposite end to feed combustion, and breathe the smoke thus produced into his oral cavity.

Cigarettes can be of the following types:

- without filter, when only made up of a paper cylinder containing tobacco;

- with filter, when one of the cylinder ends is fit with a cylindrical tipping made of filtering material, through which the smoke is made to flow before being drawn into the oral cavity of the smoker.

Cigarettes currently available on the market feature different lengths and diameters, according to the size of the paper cylinder, and different types of filters.

During the cigarette manufacturing phase, those that don't match the required quality criteria are rejected; to the purpose of reducing costs connected to rejected cigarettes, the tobacco contained therein must be recovered.

To this purpose, a suggestion has been given, to tear the paper cylinder containing tobacco and recover the tobacco contained therein. This is made by means of machines using water and/or steam jets to ensure an easier recovery of tobacco. The inconvenience of using said known machines is that the paper and the filter can be broken into even very small pieces that are difficult to separate from tobacco. Therefore, the tobacco recovered from the cigarettes contains also residues of paper and filtering material.

Moreover, there are known machines wherein the tobacco is extracted via an air jet blown at one end of the cigarette, but such types of machines do not remove the problem completely because:

- to ensure that the cigarettes face towards the air jet, they must be previously pointed to the latter by the operator, manually or by means of complex positioning systems,

- they are provided with one or more feeding rollers as well as various rollers equipped with blowing devices; it is therefore necessary to coordinate the rotation speed of the existing rollers and also such machines need a cigarette transferring device between such rollers,

- tightness between the blowing devices and the filter is not ensured and consequently the tobacco is not completely ejected from the cigarette, with greater consumption of blowing air.

Furthermore, some cigarettes are known wherein the filter encloses a small ball containing aromatic matter, e.g. menthol; when the ball is squeezed by the smoker, its aroma diffuses in the filter and flavours the smoke.

When these types of cigarettes are out of specification, the flavour ball contained in the filter must be recovered together with tobacco.

The main aim of this invention is to remove the inconveniences of a traditional device, providing a method and an apparatus to recover tobacco from the cigarettes with filter out of specification, without tearing their paper cylinder and/or filter.

Another aim of the invention is to provide a method and an apparatus to recover the tobacco from cigarettes and collect it separately from the other cigarette parts, even if the paper cylinder or filter are torn.

Another aim of the invention is to provide a method and an apparatus that do not need preliminary positioning of the cigarettes to be treated, nor transferring of the same through different rollers.

Another aim of the invention is to provide a method and an apparatus also ensuring the recovery of the flavour balls enclosed in the filter.

Another aim of the invention is to provide an apparatus which is reliable, simple, inexpensive and not too bulky.

All these aims and others that will become better apparent hereafter, are achieved, according to this invention, by means of a method for the recovery of tobacco from the cigarettes with filter, having the features of claim 1 and by means of an apparatus having the features of claim 7.

The present invention is further clarified in the accompanying drawings, wherein:

figure 1 is a perspective view of an apparatus for recovery of tobacco from cigarettes with filter, according to the present invention, figure 2 is a front view,

figure 3 is a cross section perpendicular respect to the rotor rotation axis, figure 4 is a cross section perpendicular respect to the rotation axis of the rotor of an enlarged detail of the cigarette pre-treatment station, figure 5 is a cross section through the rotor rotation axis of an enlarged detail of the air blowing nozzle in not operative position, figure 6 shows it in the same view as figure 5 in operative position, figures 7a - 7d are schematic views of the processing of a first cigarette through the apparatus stations, according to the present invention, figures 8a - 8d show in the same views as figures 7a - 7d the processing through the apparatus stations, according to the present invention, of a second cigarette, having the filter positioned at the opposite end compared to the first cigarette,

figure 9 shows the apparatus according to the present invention in the same view as figure 3 in a different embodiment,

figures 10a-10d show in the same views as figures 7a-7d the process carried out on the cigarette's filter through the apparatus stations, according to the embodiment shown in figure 9.

As shown in the figures, the apparatus according to the present invention for the recovery of tobacco from the cigarettes with filter 4, includes a cylindrical rotor 6 rotating around an horizontal axis and provided with a lot of seats on its side surface 8, and each seat is shaped in a way to house one cigarette 2 from which the tobacco must to be recovered. The cigarette seats 8 consist of semi-cylindrical grooves located at constant pitch along the rotor side surface 6, and having a diameter little longer than that of cigarettes 2.

Each seat 8 is provided with needles 10, 10', designed to be introduced in the filter 4 of the cigarette 2 housed in its seat in order to prevent any axial motion. Particularly, the ends of each seat 8 are provided with small holes enabling insertion of as many needles 10, 10', which are moved in axial direction driven by a fixed cam shaft, not shown in the figures.

As the needles are provided at both ends of each seat, and due to the fact that they must operate in different positions according to the cigarette 2 orientation, two cams have been provided to act selectively on needles 10 and 10' that are positioned at each end of seats 8, and inclined at different angles one from another.

The apparatus 2 is provided with a unit (not shown in figures) for the coordination, management and control of the operation phases and of the parts which perform such operations.

The rotor 6 is divided into sectors 14, having the same amplitude, and is operated by an electrical motor by steps having the same angular amplitude as sectors 14, so that each of them passes in sequence through the stations of apparatus 2.

In the example described herein, each sector 14 includes six seats 8, to enable a cyclical transfer of groups of six cigarettes 2 from one station to the following one.

The rotor 6 is driven in stepper mode by an electrical motor 12; in the embodiment shown in figure 1 the steps of the rotor 6 have an angular amplitude of 60°, while in the embodiment shown in figure 9 and described below, the amplitude of the steps of the rotor 6, which consists of nine sectors 14, is 40° each. In this case, the rotor diameter is longer, in order for each group to include six seats 8 for as many cigarettes to be processed.

According to a different embodiment, the rotor 6 can be replaced by a belt conveyor provided with transverse seats for the cigarettes. As already said, the rotor 6 cyclically shifts each of its sectors 14 through the following stations of the apparatus, as described here below.

The first station 16 is for the feeding of the cigarettes to be emptied and is located in the upper part of the apparatus. This station is equipped with a feeder 18 for the cigarettes to be emptied; it includes a tank 20 which, due to its construction and to the inclination of its inner walls, enables positioning of cigarettes 2 with axis parallel to the axis of the rotor 6 and consequently of the seats 8 located therein. Thus, the cigarettes falling by gravity are taken into each of the seats 8, that are conveyed to pass through the discharge opening of feeder 18 by the rotation of the rotor 6.

To prepare cigarettes 2 for the following tobacco emptying process, a pre-treating station 22 has been advantageously installed downstream to the feeder 18; such station consists of an upper flat surface 24 and a belt conveyor 26, placed underneath it at a distance shorter than the average diameter of cigarettes 2. Thus, the cigarettes located at the upstream portion of the pre-treating station 22 are transferred from the belt conveyor 26 to the downstream portion of said station and are contemporarily kept pressed against the surface 24 and made to roll along the same, to the purpose of loosening and softening the tobacco contained therein and help an easier ejection of the same from cigarettes.

The second station is station 28 for detecting the orientation of the cigarettes located in the relevant seats 8, i.e. the station where a reading is carried out to assess at which end of the cigarette there is the filter 4. This station is equipped with six optical sensors 30, placed at one side of the rotor 6 and lined with the seats 8 of sector 14 which, during reading, is stopped at the second station 28. Six LEDs are placed at the opposite end of the rotor 6 and lined with the six sensor 30.

Based on the readings carried out by sensors 30, the control unit can determine if in a seat there is a cigarette 2 and, in this case, which end of it has the filter 4.

The second station 28 is also provided with a multiple fixed metal band 34, which also covers the following stations and is designed to hold the cigarettes 2 inside their seats 8 and prevent them from getting out while enabling insertion of the needles 10, 10' inside the filter 4 of such stations.

The third station is the first discharging station 36 for all cigarettes 2 that are provided with the filter 4 located at the same end, and are held at this end by needles 10. This station is provided with a first nozzle 38, positioned with axial orientation in front of each seat 8.

With reference to figures 5 and 6, each nozzle 38 consists of a tubular element 40 fit on a stem 42, one section of which has an inner channel 44 for part of its length; the upstream end of the channel is provided with openings 46 to enable communication with the external surface of the stem itself. The upstream end of the stem 42 is swollen in a shape of a small piston 48, which slides inside a corresponding cylinder 50; the latter is provided with three separate air inlets: the first one 52 is located close to its upstream end; the second one 54 is located in its central section; the third one 56 is located close to the downstream end.

Furthermore, the first air inlet 52 is connected to a compressed air source by means of a magnetic valve (not shown in figures), operated by a control unit; the second inlet 54 is constantly connected with the same compressed air source, while the third inlet 56 is constantly connected to a more powerful air source at an adjustable pressure value.

Suitable tobacco collecting devices are located on rotor 6, facing third station 36 at the side opposite to the first group of nozzles 38. Such devices comprise a duct 58 located in front of each seat 8 of the rotor 6, connected to one common tobacco container 60.

The fourth station is an intermediate station 62, for the preparation to the emptying of all the cigarettes 2 that have not been already emptied at the station 36, because their filters 4 are located at the opposite end compared to the cigarettes emptied at the third station 36.

Therefore, at fourth station 62, the first cam is shaped in such a way as to draw all needles 10 back into their seats 8, while the second cam is shaped in such a way as to push the needles 10' out of their seats.

The fifth station is the second station for emptying cigarettes 2 and differs from third station 36 in that it is provided with a second group of nozzles 38' that are identical with the first nozzles 38, but are located at the opposite side of rotor 6. The fifth station 64 is also provided with tobacco collecting devices consisting of six tobacco collection means 58', facing the seats 8 at the opposite end of the second nozzles 38' and connected to the same tobacco collecting container 60.

The two metal bands 34 which hold the cigarettes 2 inside the relevant seats 8, run from the second station 28 to the fifth station 64.

The sixth station is the station 66 for the discharging of the emptied cigarettes into a suitable container 68. To this purpose, the second cam is constructed in such a way that the second needles 10' are drawn back into the relevant seats 8 and that the cigarettes, free of needles 10' and of the metal bands 34, are enabled to slip out of their seats 8 and fall into said container 68.

According to the present invention, the apparatus operation is the following:

cigarettes 2 with filter 4 to be emptied are fed from the upstream end of the pretreatment station 22, between the belt conveyor 26 and the flat surface 24, in order for the belt conveyor to move them towards the end downstream, while rolling them and squeezing them radially to loosen and soften the tobacco contained therein.

From the pretreatment station 22, cigarettes fall by gravity into the tank 20, from which they are then taken one by one from the rotor 6 which collects them in the following seats 8.

After the first rotation step of the rotor, that sector 14, which has been just fed, is located at the second station 28 for the detection and the cigarettes 8 (six or less depending on the number of cigarettes that have been correctly fit into their seats) are held in their six seats by two bands 34, with filters located at one or the other end.

When the rotor is stopped with the sector 14 at the detection station 28, each of the optical sensors 30 positioned close to seats 8 detects the presence and the orientation of the sigarette housed in the seat facing it. In detail, if the sensor 30 detects the light of the LED located in front of it, at the opposite end of the rotor 6, this means that this seat is empty, if it detects a light-coloured surface, this means that a filter 4 of a cigarette is located in the seat facing the sensor; if it detects a dark surface, this means that the tobacco of a cigarette housed in its seat is facing the sensor.

The reading signals of the six sensors 30 are transmitted to the control unit and recorded to be used at a later stage.

In the following rotation step of the rotor 6 for the transfer of the sector 14 to the first emptying station 36, the first cam drives the pushing out of the needles 10 which hold all the cigarettes 2 housed in their seats 8 (see Figure 7a). So, some of the needles 10 penetrate into filters 4 of the cigarettes and other needles penetrate into the ends without filter of the cigarettes that are fit in their seats in inverted position.

When the rotor 6 is stopped with the sector 10 at the first emptying station 36, each seat 8 faces a nozzle 38, which is in a not operative position, with magnetic valve connected to the upstream inlet 52 of cylinder 50; the latter is closed and the piston 48 is kept in limit stop position, upstream respect to cylinder 50.

At this point, the control unit sends an opening command only to the magnetic valves of nozzles 38 corresponding to their seats, where at the previous detection station, sensors 30 had detected the presence of a cigarette with filter facing them.

After activation of said magnetic valves, the air coming from the upstream inlet 52 of the relevant nozzles 34 pushes the pistons 42 to the downstream limit stops, until the corresponding tubular elements 40 match the filters 4 of cigarettes 2 (see figure 7b).

When each piston 42 reaches the downstream limit stop, its opening 46 reaches the central inlet 54 of cylinder, so that the compressed air jet entering the channel 44 goes out of the tubular element 40 of the nozzle 38 which has already matched cigarettes 2 and, after crossing the filter 4, causes the ejection of tobacco through the opposite end of the cigarette into tobacco collection means 58, and from there to the tobacco collecting container 60 (see figures 7c and 7d).

During this phase, the tobacco flowing out of the cigarette is not hindered by needles 10' which in this phase are kept by the relevant cam in not operative position.

During the whole phase, each cigarette is prevented from moving axially inside the corresponding seat of needles 10 which, with the help of bands 34 stop each cigarette 2 inside the seat.

After this phase, the rotor 6 is automatically rotated by a step so that the first cam releases needles 10 from cigarettes 2 and the second cam activates needles 10' which stop the cigarettes close to the cigarette end opposite to the previous one.

By the following rotation of the rotor 6 by another step, the rotor is brought to emptying station 64, wherein, in the same way as already described for the emptying station 36, the tobacco is taken out of the cigarettes with filter located at the opposite side (see figures 8a - 8d) compared to the cigarettes processed in the third emptying station 36.

After this second emptying phase, the rotor 6 moves onward by an additional step and brings that sector 14 to the sixth discharge station 66, where the first cam activates needles 10' so that the cigarettes emptied of tobacco fall into the container 68 because in that station there are no bands 54 holding the cigarettes in the relevant seats 8. The tobacco, paper and filters can be collected in one single container provided with a sieve which enables the tobacco to flow and holds the other parts of cigarettes.

The sixth station 66, which is the discharging station, is located before the first station 18 wherein, as previously, the seats 8 are fed with new cigarettes to be emptied and the cycle starts again as described above.

Obviously, a group of cigarettes housed in the relevant seats of a sector 14 is processed like the cigarettes housed in their seats in the other sectors 14, taking into account the time differences.

In view of what is described, the apparatus for recovering tobacco from cigarettes according to this invention is much better if compared to the traditional ones and, specifically:

- it recovers tobacco without tearing the paper cylinder and/or the filter,

- it does not require a particular orientation of the cigarettes to be treated,

- its construction is simple and not too bulky, as the main volume is the rotor,

- it is highly reliable and enables high production rates,

- it operates automatically and only requires feeding of the cigarettes to be processed,

- it always enables an easy separation of tobacco from paper and filter,

- it does not need any modification for the recovery of tobacco from cigarettes without filter.

In the embodiment shown in figures 9 and 10a-10d, three additional stations are foreseen which recover the balls 70 of flavour contained in the filter 4 of the cigarettes 2. As already said, the rotor 6 of the apparatus based on the invention in this different embodiment, must have a longer diameter, as it includes sectors 14, each provided with six seats 8 for as many cigarettes 2, but cigarettes move through nine process stations instead of six.

In this apparatus, the first five stations, that is the feeding station 16, the detection station 28, the first emptying station 36, the preparation station 62 to the second emptying, and the second emptying station 64 are identical to the previous corresponding stations both in their construction and operation, so they do not require any particular description.

According to this second embodiment, differently from the previous one, the sixth station of the apparatus consists of the station 72, where cigarette filters are cut close to the flavour ball 70. To this purpose, some of the adjoining bands 34 which hold cigarettes 2 inside the corresponding seats 8 of the rotor 6, and specifically those located close to any of the cigarette ends provided with the filter 4, are extended to cover also the sixth, seventh and eighth stations.

The cutting station 72 is provided with two cutting blades 76, 76', that are located between the adjoining belts 34 and protrude from the same in a suitable way to cut crosswise the cigarettes 2 housed in their seats; cigarettes are cut by two symmetrical cuts, so that, if a blade 76 cuts the paper of an emptied cigarette, the other blade 76' cuts the filter 4 in a way to leave out flavour ball 70.

The seventh station 78 discharges the cigarette parts that do not contain flavour ball 70. The container 68 located underneath this station collects paper and parts of the filter 4. The eighth station is a station 80 for the recovery of the flavour balls

70.

This station includes at both sides of the rotor 6, and lined with the seats 8, as many pneumatic pistons 82 connected to suitable devices to operate them with axial operation towards the rotor and their insertion into the seats 8.

In this station, the bands 34 are connected to the first stop devices preventing axial motion of the filter part containing the flavour ball 70 towards the interior of corresponding seat 8. Furthermore, a second fixed stop device 88 is provided close to each piston 82.

The ninth station is the transit station 86 wherein the discharging of the filter parts containing the flavour balls 70 is substantially completed.

According to the present invention, the operation of the apparatus in this second embodiment is similar to the previous one until the second emptying at the station 64 and therefore is not described here below; instead, it is different from cutting station 72 (see figure 10a) wherein the cigarette, which is now without tobacco, is cut into three parts by the two blades 76 and 76', and more in detail in a first end portion exclusively consisting of paper, in a central portion consisting of paper and the part of filter not containing the flavour ball 70, and another end portion consisting of the filter part containing the flavour ball. Blade 76 or 76' acting on the paper of the emptied cigarette might not be able to cut the paper due to lacking of a counteraction, but this event appears to be negligible, because the main operation is the cutting of the filter. However, the cigarette portion consisting of the paper and the filter portion without the flavour ball are made to fall into collecting container 68, and the third part, which is the filter portion containing the ball, remains inside its seat 8 of the rotor 6 (see figure 10b) and, during the following rotation step of the rotor 6, is transferred to the station 80 where the flavour balls 70 are recovered.

Here, all pneumatic pistons 82 are operated in axial direction in order to penetrate into the filter portions that remain fixed inside their seats 8, thanks to the counteraction of the stopping devices 84.

The penetration of each piston into the filter portion 4 pushes the flavour ball 70 outside (see figure 10c), which can fall into a collecting container 90 underneath. When back in a non operative position, the pistons 82 also drag the portions of the filter 4 that are penetrated, until they counteract the stopping elements 88. The prosecution of the stroke of pistons backwards pulls them completely out of the filter portions (see figure 10d), and makes them fall into the collection container 68 so that the sector 14 of the rotor 6 is enabled to move to the station 86 and get ready for restarting the operation cycle, thus starting to feed the following station 16 with new cigarettes 2 to be processed as described above.

In view of what is described, it clearly appears that the embodiment of the apparatus for recovery of tobacco from cigarettes according to the present invention, besides ensuring the avobe mentioned advantages, also enables recovery of the flavour balls that are enclosed in the filter.