Method and apparatus for packaging fibrous material

Abstract

A method and apparatus (1) for packaging fibrous material, in particular tobacco, are disclosed, in which a dose (D) of fibrous material is fed into a movable discharge tube (2) extending along a longitudinal axis (X) and having a material outlet opening (2a), and a plunger element (10) slidably disposed within the discharge tube (2), a bag (B) is positioned in a filling zone (8) such that an open end of the bag (B) is positioned in alignment with the material outlet opening (2a), the plunger element (10) is moved toward the material outlet opening (2a) to push the dose (D) of the fibrous material toward the bag (B), wherein a portion of the discharge tube (2) is positioned inside the bag (B) causing the dose (D) of the fibrous material to be released into the bag (B) while the material outlet opening (2a) remains within the bag (B).

Description

Method and apparatus for packaging fibrous material Background of the invention

[0001] The invention relates to a method and an apparatus for packaging fibrous material, such as tobacco.

[0002] More specifically, but not exclusively, the invention is applicable to the packaging of predefined quantities of fibrous material into individual packaging units, such as tobacco pouches.

[0003] In particular, reference is made to a method of the type defined in the preamble of claim 1. A method of this type is known from patent publication EP 2546151 Bl. According to EP 2546151 Bl, the fibrous material, for example tobacco, is first compressed and subsequently pushed into a bag, such as a tobacco pouch, by means of a plunger through a fixed funnel arranged at an upper opening of the bag.

[0004] However, due to the impulse exerted by the plunger to force the fibrous material into the bag, the known method is not fully effective in preventing dispersion of a portion of the fibrous material, which may escape from the bag. In particular, the impulse generated by the plunger can produce air vortices or turbulence that entrain part of the fibrous material and carry it out of the bag, thereby causing product loss and reducing the accuracy of the quantity of product contained in the final package.

[0005] In order to reduce the risk of dispersion of the fibrous material and its escape from the bag, it is known to reduce the speed of the plunger during the thrust phase. Such a measure, however, results in a reduction in the productivity and throughput of the packaging process.Summary of the invention

[0006] The present invention addresses and overcomes one or more of the limitations and drawbacks of the prior art discussed above.

[0007] In particular, an object of the invention is to provide a method and an apparatus for packaging fibrous material that reduce or eliminate dispersion of the fibrous material during introduction into a bag.

[0008] Another object of the invention is to ensure accurate and repeatable dosing of the quantity of fibrous material contained in a final package.

[0009] A further object of the invention is to enable the packaging of doses of fibrous20251908 WO ENmaterial with high productivity and throughput.

[0010] Another object is to protect the fibrous material from air vortices or turbulences during its insertion into the bag.

[0011] Yet another object of the invention is to provide a packaging method and apparatus capable of achieving high productivity while minimizing or preventing product dispersion.

[0012] The above objects are achieved by a method and an apparatus according to one or more of the appended claims.

[0013] According to one aspect of the invention, the method comprises the steps of providing a discharge tube extending along a longitudinal axis and having a material outlet opening, and a plunger element slidably arranged within the discharge tube; feeding a dose of fibrous material into the discharge tube; positioning a bag in a filling zone such that an open end of the bag is aligned with the material outlet opening; moving the plunger element toward the material outlet opening to advance the dose of fibrous material toward the bag; inserting at least a portion of the discharge tube into the bag; and releasing the dose of fibrous material into the bag while the material outlet opening remains positioned inside the bag.Brief description of the drawings

[0014] The invention will be better understood from the following description, given by way of example and not limitation, with reference to the accompanying drawings, in which:Fig. l is a perspective view of an exemplary apparatus for packaging doses of fibrous material, such as tobacco, according to the present invention;Fig. 2 is a partial vertical sectional view of the apparatus shown in Fig. 1;Figs. 3 - 17 illustrate successive steps of operation of the apparatus of Fig. 1 during a complete cycle of filling a single bag with a single dose of fibrous material;Fig. 18 is a side elevational view of a packaging system comprising a plurality of packaging apparatuses of the type shown in Fig. 1; andFig. 19 illustrates an example of filling a single bag with two doses of fibrous material, wherein each dose is processed by a respective packaging apparatus of the type shown in Fig. 1, such that two packaging apparatuses are operatively associated20251908 WO ENwith the single bag.Detailed description

[0015] With reference to the accompanying drawings, reference numeral 1 generally designates a packaging apparatus for packaging doses D of fibrous material, such as tobacco.

[0016] The packaging apparatus 1 comprises a discharge tube 2, which may be formed, for example, as a cylindrical body. The discharge tube 2 extends along a longitudinal axis X, which, preferably, is oriented substantially vertically.

[0017] The discharge tube 2 defines a material outlet opening 2a configured to discharge the dose D of fibrous material from the discharge tube 2 in an axial direction substantially parallel to the longitudinal axis X. The material outlet opening 2a is arranged at a lower end of the discharge tube 2. The discharge tube 2 further defines a lateral feed opening 2b. In some embodiments, the lateral feed opening 2b is formed in a lateral wall 2c of the discharge tube 2. The lateral feed opening 2b is configured to introduce the dose D of fibrous material into the discharge tube 2 along a feed direction F, which is preferably transverse, and more preferably substantially perpendicular, to the longitudinal axis X. The lateral feed opening 2b is arranged in an upper portion of the discharge tube 2.

[0018] The packaging apparatus 1 further comprises feeding means configured to feed a dose D of fibrous material into the discharge tube 2.

[0019] The feeding means include a feed chamber 3 configured to receive and deliver the dose D of fibrous material to the discharge tube 2. The lateral feed opening 2b places the feed chamber 3 in fluid communication with the discharge tube 2.

[0020] The feeding means further comprise a presser element 4 configured to move within the feed chamber 3 to push the dose D of fibrous material through the lateral feed opening 2b, thereby forming a compacted dose D to be discharged through the discharge tube 2. According to one embodiment, the presser element 4 is movable along a direction transverse, and preferably substantially perpendicular, to the longitudinal axis X of the discharge tube 2. In particular, the presser element 4 may be configured to move within the feed chamber 3 along a substantially horizontal direction. The presser element 4 may include a closing plate 4a configured to open a transfer opening 3 a of the feed chamber 3 when moving away from the discharge tube 2, thereby allowing the dose D of fibrous20251908 WO ENmaterial to enter the feed chamber 3, and to close the transfer opening 3a when moving toward the discharge tube 2. Preferably, the transfer opening 3a lies in a plane substantially parallel to the feed direction F.

[0021] The presser element 4 may further comprise an axially movable piston arranged within the feed chamber 3. According to some embodiments, the presser element 4 is actuated by pressing actuating means 4b. The pressing actuating means 4b may be controlled by a drive system H or by another controller.

[0022] According to some embodiments, the presser element 4 is configured to be at least partially inserted into the discharge tube 2, in particular by passing through the lateral feed opening 2b.

[0023] In some embodiments, the feed chamber 3 is rigidly connected to the discharge tube 2, such that the feed chamber 3 moves together with the discharge tube 2, as well as with the presser element 4 and the pressing actuating means 4b associated therewith.

[0024] According to different embodiments the feed chamber 3 is disconnected at least from a portion of the discharge tube 2. In particular, a lowermost portion of the discharge tube 2, arranged in proximity to a filling zone 8, may be configured to be movable along the longitudinal axis X and displaceable relative to the feed chamber 3, or relative to both the feed chamber 3 and an upper portion of the discharge tube 2 that may be rigidly connected to the feed chamber 3. Advantageously, in such embodiments, the material outlet opening 2a is formed in the lowermost portion of the discharge tube 2.

[0025] The feeding means also comprise a hopper 5 configured to receive the dose D of fibrous material and to allow the transfer of the dose D of fibrous material by gravity into the feed chamber 3 through the transfer opening 3a.

[0026] The presser element 4 is movable within the feed chamber 3 between a rearward position, in which the presser element 4 opens the transfer opening 3a to allow transfer by gravity of the dose D of fibrous material from the hopper 5 into the feed chamber 3, and a forward position, in which the presser element 4 pushes the dose D of fibrous material from the feed chamber 3 into the discharge tube 2. In the forward position, the presser element 4 may simultaneously close the transfer opening 3a by means of the closing plate 4a, thereby allowing the hopper 5 to receive and temporarily retain a subsequent dose D of fibrous material.20251908 WO EN

[0027] The hopper 5 comprises a first portion 6 that is movable and rigidly connected to the feed chamber 3, and a second portion 7 that is fixed and coupled to the first portion 6 in a displaceable manner. In particular, the second portion 7 is coupled to the first portion 6 by means of a telescopic coupling, such that the first movable portion 6 moves together with the feed chamber 3, while the second portion 7 remains fixed and continues to define a containment volume for the fibrous material within the hopper 5. The first movable portion 6 is arranged below the second fixed portion 7 and is movable relative thereto along a substantially vertical sliding direction.

[0028] The packaging apparatus 1 further comprises the filling zone 8 configured to receive a bag B such that an open end of the bag B is positioned in alignment with the material outlet opening 2a of the discharge tube 2, preferably along the longitudinal axis X of the discharge tube 2. The packaging apparatus 1 further includes positioning means configured to position the bag B in the filling zone 8. The positioning means may be of a known type and may comprise, for example, a horizontal conveyor T (shown in Fig. 18) configured to transport a series of bags B and to cyclically position a bag B in the filling zone 8 beneath the discharge tube 2 to receive a dose D of fibrous material therefrom. In some embodiments, the bags B are conveyed to the filling zone 8 in a suspended configuration. The positioning means may further comprise, for each packaging apparatus 1, gripping elements 9, such as grippers, arranged on opposite sides of the bag B positioned in the filling zone 8 and configured to open an upper inlet opening of the bag B to permit filling of the bag B with the dose D of fibrous material.

[0029] The discharge tube 2 is movable along the longitudinal axis X toward and away from the bag B. In particular, the discharge tube 2 is movable between a distal (upper) position, in which the material outlet opening 2a of the discharge tube 2 is positioned outside the bag B, and a proximal (lower) position, in which the material outlet opening 2a of the discharge tube 2 is positioned inside the bag B at the filling zone 8.

[0030] The packaging apparatus 1 further comprises a plunger element 10 configured to be slidably movable within the discharge tube 2 along the longitudinal axis X and configured to urge the dose D of fibrous material toward the material outlet opening 2a. The plunger element 10 is movable within the discharge tube 2 to contact and retain the dose D of fibrous material contained within the discharge tube 2 when the discharge tube 220251908 WO ENis withdrawn from the bag B by movement from the proximal position toward the distal position. The plunger element 10 comprises a lower surface 10a located at a lowermost portion of the plunger element 10 and facing the material outlet opening 2a when the plunger element 10 is disposed within the discharge tube 2.

[0031] In some embodiments, the plunger element 10 comprises a piston and a stem, the piston being arranged at a lower end of the stem.

[0032] The discharge tube 2 is movable relative to the plunger element 10. Preferably, the discharge tube 2 and the plunger element 10 are configured to be movable independently of one another. In some embodiments, the discharge tube 2 is movable between the distal position and the proximal position along a substantially vertical direction. The discharge tube 2 and the plunger element 10 are movable along respective motion axes that are parallel to one another, and preferably along a common motion axis. Preferably, the common motion axis is substantially parallel to the longitudinal axis X of the discharge tube 2.

[0033] In a preferred embodiment, the drive system H is further configured to control the motion of at least the plunger element 10 and the discharge tube 2. The drive system H may be an electronic and programmable controller, for example an electronic processor, configured to control and coordinate the motion of various actuators of the apparatus during the different steps and to perform the method described herein. Coordination of the motion of the plunger element 10 and the discharge tube 2 is important to achieve precise and efficient packaging. In other embodiments, the drive system H may be of a mechanical type, configured to drive the motion of at least the plunger element 10 and the discharge tube 2 through a mechanical system, such as a cam mechanism. Preferably, the drive system H is configured to control movement of the plunger element 10 toward the material outlet opening 2a, and to control insertion of at least a portion of the discharge tube 2 into the bag B so that the dose D of fibrous material is released into the bag B while the material outlet opening 2a remains within the bag B.

[0034] According to an embodiment, at least the lowermost portion of the discharge tube 2, arranged in proximity to the filling zone 8, is movable along the longitudinal axis X and displaced relative to the feed chamber 3, or relative to both the feed chamber 3 and an upper part of the discharge tube 2. The drive system H is configured to control movement20251908 WO ENand insertion of the lowermost portion of the discharge tube 2 into the bag B, so that the dose D of fibrous material is released into the bag B while the material outlet opening 2a remains within the bag B.

[0035] In a preferred embodiment, the drive system H may independently control separate actuating members configured to move the discharge tube 2 and the plunger element 10. Accordingly, the drive system H independently controls a first actuating member 11, configured to move the discharge tube 2 along the vertical direction, and a second actuating member 12, configured to move the plunger element 10 along the vertical direction. Preferably, the first actuating member 11 and the second actuating member 12 are linear actuators.

[0036] The packaging apparatus 1 further comprises a spreader 13 including at least one finger or flange extending around the discharge tube 2 and configured to hold open an edge of the open end of the bag B in the filling zone 8 when the discharge tube 2 is positioned inside the bag B, for example when the discharge tube 2 is in the proximal position.

[0037] The spreader 13 is arranged outside the discharge tube 2 such that the spreader 13 is interposable between the discharge tube 2 and the bag B.

[0038] The packaging apparatus 1 further comprises a moving device 14, for example comprising a cam-type mechanism, configured to move the spreader 13 along a distance-and-approach path, e.g., linear movements, in particular in a vertical direction, with respect to the filling zone 8, and to activate opening and closing movements, e.g., rotary movements, of the at least one finger or flange of the spreader 13. Preferably, the drive system H controls the motion of the moving device 14, thereby coordinating the movements of the spreader 13, the discharge tube 2, and the plunger element 10 throughout all steps of the packaging method. The spreader 13 is configured to assume a closed configuration, in which it closes the material outlet opening 2a of the discharge tube 2 to stop and retain the fibrous material inside the discharge tube 2, and an open configuration, in which it opens the material outlet opening 2a and maintains the edge of the open end of the bag B widened.

[0039] The packaging apparatus 1 comprises a frame on which at least the first actuating member 11, the second actuating member 12, and the moving device 14 are20251908 WO ENmounted, either directly or via elements connected thereto. This arrangement provides a common coordinate reference, thereby facilitating control of the motions of the packaging apparatus 1.

[0040] Figures 3 to 17 illustrate an example of a filling cycle for a bag B, in particular a tobacco pouch.

[0041] Figure 3 shows a step of introduction of a dose D of fibrous material into the hopper 5. In this step, the presser element 4 (in the advanced position) blocks a lower discharge opening of the hopper 5, such that the dose D of fibrous material is temporarily retained in the hopper 5 and is prevented from falling into the underlying feed chamber 3 (Figure 4). Figure 5 illustrates a retraction step of the presser element 4. The presser element 4 is moved to the retracted position, thereby allowing the dose D of fibrous material to fall from the hopper 5 into the feed chamber 3. Thereafter, the presser element 4 returns to the advanced position, pushing the dose D of fibrous material toward the lateral feed opening 2b of the discharge tube 2, which is positioned in the distal (upper) position (see Figure 6).

[0042] In Figure 7 the presser element 4 (in the advanced position) pushes the dose D of fibrous material into the discharge tube 2. The plunger element 10, which may subsequently function as a pushing piston, is positioned above the dose D within the discharge tube 2. The spreader 13 (positioned by the moving device 14 at the height of the material outlet opening 2a of the discharge tube 2) is in the closed configuration and obstructs the material outlet opening 2a. Any particles of fibrous material that might fall from the discharge tube 2 are retained within the discharge tube 2, preventing escape.

[0043] The discharge tube 2 (containing the dose D of fibrous material), the plunger element 10 (slidably disposed within the discharge tube 2 and configured to push the fibrous material downward), and the spreader 13 (maintaining the material outlet opening 2a of the discharge tube 2 in the closed configuration to prevent material escape), are then moved downward toward the underlying filling zone 8 (Figure 8).

[0044] The discharge tube 2 and the plunger element 10 may be moved downward by the respective first and second actuating members 11 and 12, while the spreader 13 is moved downwards by the moving device 14. The actuating members 11, 12 and the moving device 14 may operate independently from one another.20251908 WO EN

[0045] During the downward movement, the plunger element 10 may be operated at a descent speed greater than that of the discharge tube 2, so as to slide within the discharge tube 2 and push the dose D of fibrous material contained therein downward. The descent speed of the spreader 13 may be equal to the descent speed of the discharge tube 2, such that the spreader 13 moves in unison with the discharge tube 2.

[0046] When the material outlet opening 2a of the discharge tube 2 reaches the open end of the bag B (stationary at the filling zone 8), the spreader 13 transitions to the open configuration to maintain the edge of the open end of the bag B widened, while the discharge tube 2 and the plunger element 10 continue their respective downward movements without interruption (Figure 9).

[0047] It is noted that any fibrous material that may have prematurely separated from the pressed dose D may exit the discharge tube 2, but will not escape from the bag B, since the material outlet opening 2a of the discharge tube 2 is already positioned at the open end of the bag B.

[0048] The discharge tube 2 and the plunger element 10 may continue their respective downward movements (operated independently of one another), while the spreader 13 may remain stationary in the open configuration, maintaining the open end of the bag B widened.

[0049] The discharge tube 2 may be axially movable within the spreader 13. The plunger element 10 may be slidably movable within the discharge tube 2. In Figure 10, the material outlet opening 2a of the discharge tube 2 and the lower surface 10a of the plunger element 10 have passed the level of the open end of the bag B, such that a portion of the discharge tube 2 is inserted into the bag B (stationary in the filling zone 8).

[0050] In this advanced position, the plunger element 10 occludes the lateral feed opening 2b of the discharge tube 2, and at least a portion of the discharge tube 2 is inserted inside the bag B.

[0051] It should be noted that during the insertion step, the dose D of fibrous material enters the bag B while remaining contained within the discharge tube 2, except for any fraction of fibrous material that may detach from the pressed dose D, which will nonetheless fall into the bag B. The majority of the dose D of fibrous material enters the bag B while still contained within the discharge tube 2, and thus is protected by the20251908 WO ENdischarge tube 2. The fibrous material is prevented from escaping the bag B, for example due to air vortices or turbulence that may be generated during the insertion step.

[0052] At a predetermined point, the downward movement of the discharge tube 2 is stopped, and an upward movement of the discharge tube 2 begins (Figure 11). The moment at which the discharge tube 2 stops descending is controlled by the drive system H and may be programmed based on various operating parameters, including the quantity of the dose D of fibrous material, the type of fibrous material, the characteristics of the bag B, and the characteristics of the discharge tube 2. In particular, as the height of the bag B varies, the stroke of the discharge tube 2 will correspondingly vary. In the specific example shown in the figures, the bags B arrive in the filling zone 8 hanging, such that the position of the upper mouth of the bag B remains substantially constant (zero position), while the position of the bottom of the bag B varies according to the bag height.

[0053] Thereafter, the drive system H commands the plunger element 10 to stop its descent and initiate its upward movement. The sequence and timing of the discharge tube 2 and plunger element 10 during descent stoppage and ascent may be implemented in various ways. For example, one embodiment may follow the sequence: stop descent of the discharge tube 2, stop descent of the plunger element 10, start ascent of the discharge tube 2, and start ascent of the plunger element 10. In another embodiment, the sequence may be as follows: stop descent of the discharge tube 2, start ascent of the discharge tube 2, stop descent of the plunger element 10, and start ascent of the plunger element 10. Alternative embodiments may involve simultaneous events or other variations.

[0054] According to certain embodiments, the drive system H may be configured to control the retraction of the discharge tube 2 from the bag B while the dose D of fibrous material is being released from the discharge tube 2, and to control the motion of the plunger element 10 so as to ensure complete release of the dose D into the bag B before the material outlet opening 2a of the discharge tube 2 exits the bag B. During this retraction step, the plunger element 10 operates in contact with the fibrous material to facilitate complete discharge of the dose D into the bag B as the discharge tube 2 is extracted. The plunger element 10 exerts a controlled counteracting force against the upward movement of the fibrous material, thereby ensuring that all fibrous material contained within the discharge tube 2 exits the discharge tube and remains within the bag B.20251908 WO EN

[0055] The discharge tube 2 and the plunger element 10 may stop simultaneously (Figure 12), in respective positions such that the material outlet opening 2a is positioned closer to the bottom of the bag B than the lower surface 10a of the plunger element 10. Thereafter, the discharge tube 2 begins its upward movement, while the plunger element 10 may remain stationary.

[0056] The discharge tube 2 continues to rise in its retraction movement until the material outlet opening 2a reaches the same vertical height as the lower surface 10a of the plunger element 10, i.e., the surface of the plunger element 10 that is in contact with the fibrous material to facilitate complete removal of the dose D from the discharge tube 2 (Figure 13).

[0057] Subsequently, the plunger element 10 begins its upward movement while the discharge tube 2 continues its uninterrupted retraction (the spreader 13 may remain stationary in its open configuration). This coordinated movement continues until both the plunger element 10 and the discharge tube 2 reach the height of the spreader 13, corresponding to the open end of the bag B (Figure 14). Immediately after the plunger element 10 and the discharge tube 2 pass through the spreader 13 and exit the bag B, the spreader 13 may close (Figure 15). Thereafter, the spreader 13 begins to move upward, so that all three elements — the spreader 13, the plunger element 10, and the discharge tube 2 — move upward simultaneously (Figure 16).

[0058] Meanwhile, a new dose D of fibrous material is introduced into the hopper 5, allowing the spreader 13, the plunger element 10, and the discharge tube 2 to return to their initial positions to begin a new filling cycle with the new dose D and a new bag B, positioned at the filling zone 8 (Figure 17, corresponding to Figure 4). In one embodiment, the first portion 6 of the hopper, the feed chamber 3, and the presser element 4 are rigidly connected to the discharge tube 2, so that these elements move together with the discharge tube 2 along the longitudinal axis X.

[0059] Accordingly, a new dose D may be fed into the hopper 5 when the presser element 4 is in its advanced position and the transfer opening 3a is closed (Figure 7). The presser element 4 can then be retracted to reopen the transfer opening 3a and allow introduction of the new dose D into the feed chamber 3. This arrangement prevents mixing of the contents of doses D from two successive filling cycles, particularly when the plunger20251908 WO ENelement 10, sliding inside the discharge tube 2, has already blocked the lateral feed opening 2b and the discharge tube 2 is at least partially inserted into the bag B (e.g., in the configuration of Figure 10). Such coordination enables a faster subsequent filling cycle with the new dose D. Typically, the presser element 4 is controlled by the drive system H to synchronize operation of the entire packaging apparatus 1.

[0060] Figure 18 illustrates an example of a packaging machine 100 comprising a plurality of packaging apparatuses 1 constructed as described above and arranged side by side.

[0061] The packaging machine 100 further comprises a feeding system 15, for example of a known type, configured to supply fibrous material to the plurality of packaging apparatuses 1. The feeding system 15 is configured to deliver single doses D of fibrous material (e.g., tobacco) into the respective hoppers 5 of the various packaging apparatuses 1.

[0062] Figure 19 illustrates an example in which a single bag B is filled using two packaging apparatuses 1 arranged side by side, such that the total quantity of fibrous material in the bag B corresponds to the sum of two doses D. It will be appreciated that a single bag B may alternatively be filled using three, four, or more packaging apparatuses 1, thereby introducing three, four, or more doses D. Accordingly, the single packaging apparatus 1 may serve as a modular element to create a flexible system suitable for producing various packaging formats depending on production requirements.

[0063] Accordingly, the packaging apparatus 1 comprises a discharge tube 2, a plunger element 10, a feed chamber 3, a filling zone 8, and a drive system H, wherein: the discharge tube 2 extends along a longitudinal axis X, has a material outlet opening 2a, and is movable along the longitudinal axis X;the plunger element 10 is configured to be slidably movable within the discharge tube 2 along the longitudinal axis X and to push a dose D of fibrous material toward the material outlet opening 2a;the feed chamber 3 is configured to deliver a dose D of fibrous material to be discharged through the discharge tube 2;the filling zone 8 is configured to receive a bag B such that an open end of the bag B is aligned with the material outlet opening 2a along the longitudinal axis X; and20251908 WO ENthe drive system H is configured to control the motion of the plunger element 10 toward the material outlet opening 2a and to control the insertion of at least a portion of the discharge tube 2 into the bag B, so as to release the dose D of fibrous material into the bag B while the material outlet opening 2a remains positioned within the bag.

[0064] The operation of the packaging apparatus 1 described above implements a method of packaging fibrous material, such as tobacco, comprising the steps of providing a discharge tube 2 extending along a longitudinal axis X and having a material outlet opening 2a at a longitudinal end thereof, and a plunger element 10 slidably disposed within the discharge tube 2;feeding a dose D of fibrous material into the discharge tube 2;positioning a bag B in a filling zone 8 such that the open end of the bag B is aligned with the material outlet opening 2a;moving the plunger element 10 toward the material outlet opening 2a to push the dose D of fibrous material toward the bag B;inserting at least a portion of the discharge tube 2 into the bag B; andreleasing the dose D of fibrous material into the bag B while the material outlet opening 2a remains positioned inside the bag.

[0065] In particular, the discharge tube 2 is movable along the longitudinal axis X from a distal position, in which the material outlet opening 2a is positioned near the open end of the bag B and distant from the bottom of the bag, to the proximal position, in which the material outlet opening 2a is closer to the bottom of the bag. This arrangement allows the dose D of fibrous material to enter the bag B while remaining protected within the discharge tube 2, thereby preventing scattering or dispersion caused by air currents, vortices, or turbulence. Preferably, during the insertion step, the discharge tube 2 is moved toward the bag B along the longitudinal axis X while the plunger element 10 simultaneously moves toward the material outlet opening 2a.

[0066] According to an embodiment, the packaging method further comprises an extraction motion of the discharge tube 2 from bag B, in which, during the extraction motion (from the proximal position towards the distal position), the plunger element 10 inserted in the discharge tube 2 contacts and retains the fibrous material, favoring the20251908 WO ENcomplete exit of the dose D from the discharge tube 2 while ensuring that the entire dose D remains inside the bag B. The motion of the plunger element 10 ensures that all the fibrous material is pushed out of the discharge tube 2 and simultaneously guarantees that it remains contained within the bag B.

[0067] The extraction motion of the discharge tube 2 from the bag B may, in particular, follow a direction opposite to the insertion motion of the discharge tube 2 into the bag B. In the example described the insertion and extraction motions of the discharge tube 2 are vertically axial movements, first descending and then ascending.

[0068] It should be noted that the insertion motion of the discharge tube 2 (i.e., the downward motion toward the bottom of the bag B) may involve, as in the example described, stopping the lower end of the discharge tube 2 (where the material outlet opening 2a is located) at a certain distance above the bottom of the bag B, before reversing direction to initiate the extraction motion (i.e., the upward movement away from the bottom of the bag B).

[0069] It is also possible to envisage embodiments in which the insertion motion of the discharge tube 2 continues until the lower end of the discharge tube 2 reaches the bottom of the bag B (i.e., at zero distance from the bottom) or near the bottom of the bag B.

[0070] As previously described, the method comprises the step of introducing a dose D of fibrous material into the discharge tube 2, which initially assumes a distal position with respect to the bag B. In the distal position, the material outlet opening 2a of the discharge tube 2 is arranged outside the bag B. By “outside the bag,” it is meant that the material outlet opening 2a is positioned at a distance from the material inlet opening of the bag B located in the filling zone 8 (as illustrated in Figures 3 to 7), or alternatively, in close proximity to, or substantially at, the material inlet opening of the bag B (as illustrated in Figures 8 and 9).

[0071] The method further comprises a relative insertion movement between the discharge tube 2 and the bag B, from the distal position to the proximal position. In the proximal position, the discharge tube 2 is at least partially inserted into the bag B through the material inlet opening, such that the material outlet opening 2a of the discharge tube 2 is at a predefined distance from the bottom of the bag B. An exemplary proximal position20251908 WO ENof the discharge tube 2 is illustrated in Figures 10 to 12. The depth reached by the discharge tube 2 in the proximal position may be selected based on various operating parameters and may also be determined empirically. In particular, the discharge tube 2 may be inserted into the bag B to a depth corresponding to at least three-quarters of the height of the bag B (where “bag height” is the distance between the bottom of the bag B and the upper material inlet opening in the filling zone 8), or at least two-thirds, at least half, at least one-third of the bag height, or even to the bottom of the bag B (i.e., zero distance from the bottom).

[0072] As previously described, the method further comprises an extraction movement in which the discharge tube 2 is withdrawn from the bag B. During this extraction movement, the slidable plunger element 10 remains in contact with the fibrous material inside the discharge tube 2, thereby fully pushing the dose D of fibrous material out of the discharge tube 2 while simultaneously ensuring that the entire dose D remains inside the bag B.

[0073] The proximal position of the discharge tube 2, as well as the descent speed of the discharge tube 2, may be selected to ensure that the complete dose D of fibrous material is delivered into the bag B without dispersion outside the bag, while simultaneously maintaining high productivity of the method.

[0074] The presence of the plunger element 10 within the discharge tube 2 — and consequently also within the bag B, as the plunger element 10 is inserted through the material inlet opening while remaining inside the discharge tube 2 — enables stable and secure positioning of the entire dose D of fibrous material within the bag B, preventing any material loss or dispersion.

[0075] The fibrous material may be introduced into the discharge tube 2 when the discharge tube 2 is in a receiving position, such as the distal position (see Figures 5 to 7). During the subsequent movement of the discharge tube 2 toward the bottom of the bag B, the plunger element 10 may simultaneously move toward the bottom of the bag B (see Figures 8 to 10), ensuring that the dose D is guided safely and efficiently into the bag B.

[0076] In some embodiments, the discharge tube 2 may be withdrawn from the bag B via a relative movement between the discharge tube 2 and the plunger element 10, such that during the relative movement, a distance between the material outlet opening 2a of the20251908 WO ENdischarge tube 2 and the bottom of the bag B increases relative to a distance between the plunger element 10 and the bottom of the bag B (see, e.g., Figures 11 and 13). In certain embodiments, the discharge tube 2 may move at a higher extraction speed than the plunger element 10. In particular, the plunger element 10 may remain stationary during at least a portion of the relative movement between the discharge tube 2 and the plunger element 10.

[0077] The bag B may be positioned at the filling zone 8 such that the bottom of the bag B is disposed below the material inlet opening of the bag B. The movement of the discharge tube 2 from a distal position to a proximal position may comprise a relative vertical movement between the discharge tube 2 and the bag B. In certain embodiments, the movement of the discharge tube 2 may be driven by an actuating member distinct from an actuating member configured to drive movement of the plunger element 10.

[0078] In certain embodiments, the movement of the discharge tube 2 from the distal position to the proximal position may comprise an axial (vertical) insertion movement of the discharge tube 2 into the bag B. Conversely, the discharge tube 2 may be withdrawn from the bag B via an axial (vertical) extraction movement opposite to the insertion movement.

[0079] The method may further comprise an axial movement of the plunger element 10 toward the bottom of the bag B during the transition of the discharge tube 2 from the distal position to the proximal position, as well as an axial return movement of the plunger element 10 during or after the extraction of the discharge tube 2 from the bag B.

[0080] When the discharge tube 2 reaches the proximal position, in which the discharge tube 2 is positioned closer to the bottom of the bag B, the plunger element 10 is inserted into the bag B in a position such that a distance between the plunger element 10 and the material inlet opening of the bag B is smaller than a distance between the material outlet opening 2a of the discharge tube 2 and the material inlet opening of the bag B. In other words, the plunger element 10 is disposed above the material outlet opening 2a of the discharge tube 2. In certain embodiments, the plunger element 10 remains in this position until the dose D of fibrous material has been completely released from the discharge tube 2 into the bag B, for example, until the material outlet opening 2a reaches the vertical height of a lower surface 10a of the plunger element 10 during the upward extraction movement of the discharge tube 2 (Figure 13).20251908 WO EN

[0081] In certain embodiments, the step of introducing the dose D of fibrous material into the discharge tube 2 comprises pushing the dose D from a feed chamber 3 into the discharge tube 2 through a lateral feed opening 2b, thereby forming a compressed dose D within the discharge tube 2 (see Figures 6 and 7). The discharge tube 2 may be integral with the feed chamber 3, such that the feed chamber 3 moves together with the discharge tube 2 during both the insertion (downward) and extraction (upward) motions (Figures 8 to H).

[0082] Prior to being pushed into the discharge tube 2, the dose D of fibrous material may be introduced into a hopper 5 in communication with the feed chamber 3, from which the dose D is transferred by gravity into the feed chamber 3 (Figures 3 to 5).

[0083] During the movement of the discharge tube 2 from the distal position to the proximal position, an edge of the material inlet opening of the bag B may be kept widened by a spreader 13 positioned between the discharge tube 2 and the bag B (see Figures 9 and 10). The spreader 13 may continue to maintain the edge of the material inlet opening widened during an initial portion of the extraction and upward movement of the discharge tube 2 and plunger element 10 (Figures 13 and 14).

[0084] In certain embodiments, the spreader 13 may assume a closed configuration, in which the spreader 13 obstructs the material outlet opening 2a of the discharge tube 2 when the material outlet opening 2a is positioned outside the bag B, thereby preventing any portion of the dose D of fibrous material from escaping prior to insertion of the discharge tube 2 into the bag B (see Figures 3 to 8). The spreader 13 may further assume an open configuration, in which the spreader 13 opens the material outlet opening 2a of the discharge tube 2 and maintains the edge of the material inlet opening of the bag B widened when the material outlet opening 2a has been inserted into the bag B (Figures 9 to 14).

[0085] The method may further comprise coupling two or more discharge tubes 2 to one another, such that multiple doses D of fibrous material may be simultaneously introduced into a single bag B, thereby enabling faster filling of larger bags.20251908 WO EN

Claims

CLAIMS1. Method for packaging a fibrous material, in particular tobacco, the method comprising the steps of:providing a discharge tube (2) extending along a longitudinal axis (X) and having a material outlet opening (2a), and a plunger element (10) slidably disposed within the discharge tube (2);feeding a dose (D) of fibrous material into the discharge tube (2); positioning a bag (B) in a filling zone (8) such that an open end of the bag (B) is positioned in alignment with the material outlet opening (2a);moving the plunger element (10) toward the material outlet opening (2a) to push the dose (D) of fibrous material toward the bag (B);the method being characterized by further comprising:inserting at least a portion of the discharge tube (2) inside the bag (B); releasing the dose (D) of fibrous material into the bag (B) while the material outlet opening (2a) remains within the bag (B).

2. Method according to claim 1, wherein during the step of inserting, the discharge tube (2) is moved along the longitudinal axis (X) toward the bag (B) while the plunger element (10) is moved simultaneously toward the material outlet opening (2a).

3. Method according to claim 1 or 2, wherein, while the dose (D) of fibrous material is being released into the bag (B), the discharge tube (2) is retracted from the bag (B), such that the dose (D) is completely released before the material outlet opening (2a) of the discharge tube (2) exits the bag (B).

4. The method of claim 3, wherein the discharge tube (2) is lowered toward a bottom of the bag (B) at the start of the release of the dose (D) of fibrous material and then raised, the dose (D) of fibrous material being completely released before the material outlet opening (2a) exits the bag.

5. Method according to claim 4, wherein, while the discharge tube (2) is raised, the plunger element (10) remains stationary with respect to the bag (B).

6. Method according to any of the preceding claims, wherein, while the dose (D) of the fibrous material is being released into the bag (B), the plunger element (10) is held near the open end of the bag (B), while the discharge tube (2) is retracted from the20251908 WO ENbag (B).

7. Method according to any of the preceding claims, wherein, while the dose (D) of fibrous material is being released into the bag (B), the plunger element (10) is completely retained within the discharge tube (2).

8. Method according to any of the preceding claims, wherein said step of feeding a dose (D) of fibrous material into the discharge tube (2) comprises pushing the dose (D) of fibrous material from a feed chamber (3) through a lateral feed opening (2b) that is in communication with the discharge tube (2).

9. Method according to any of the preceding claims, wherein, the step of feeding a dose (D) of the fibrous material into the discharge tube (2) is performed while the discharge tube (2) is outside the bag (B).

10. Apparatus for packaging a fibrous material, in particular tobacco, the apparatus (1) comprising:a discharge tube (2) extending along a longitudinal axis (X) and having a material outlet opening (2a) at a longitudinal end thereof;a plunger element (10) configured to be slidably movable within the discharge tube (2) along the longitudinal axis (X) and configured to push a dose (D) of fibrous material toward the material outlet opening (2a);a feed chamber (3) configured to deliver a dose (D) of fibrous material to be discharged through the discharge tube (2); anda filling zone (8) configured to receive a bag (B) such that an open end of the bag (B) is positioned in alignment with the material outlet opening (2a) along the longitudinal axis (X);said apparatus being characterized in that the discharge tube (2) is movable along said longitudinal axis (X) and by further comprising a drive system (H) configured to control the motion of the plunger element (10) toward the material outlet opening (2a) and configured to control the insertion of at least a portion of the discharge tube (2) into the bag (B) so as to release the dose (D) of fibrous material into the bag (B) while the material outlet opening (2a) remains within the bag (B).

11. Apparatus according to claim 10, wherein the drive system (H) is further configured to control the retraction movement of the discharge tube (2) from the bag (B) while20251908 WO ENthe dose (D) of fibrous material is being released from said discharge tube (2) and to control the motion of the plunger element (10) so as to completely release the dose (D) of fibrous material into the bag (B) before the material outlet opening (2a) of the discharge tube (2) exits the bag (B).

12. Apparatus according to claim 10 or 11, wherein the drive system (H) is further configured to keep the discharge tube (2) outside the bag (B) while the dose (D) of fibrous material is delivered into the discharge tube (2).

13. Apparatus according to any of claims 10 to 12, wherein the drive system (H) controls separate actuating members (11, 12) configured to move respectively the discharge tube (2) and the plunger element (10) independently of one another.

14. Apparatus according to any of claims 10 to 13, further comprising a lateral feed opening (2b) that places the discharge tube (2) in communication with the feed chamber (3).

15. Apparatus according to claim 14, further comprising a presser element (4) configured to move inside the feed chamber (3) to push the dose (D) of fibrous material into the discharge tube (2) through the lateral feed opening (2b), thereby forming a compacted dose (D) to be discharged through the discharge tube (2).

16. Apparatus according to claim 15, wherein the presser element (4) comprises a closing plate (4a) configured to open a transfer opening (3a) of the feed chamber (3) when moving away from the discharge tube (2), allowing the dose (D) of fibrous material to fall in, and to close the transfer opening (3a) when moving toward the discharge tube (2).

17. Apparatus according to any of claims 10 to 16, further comprising a spreader (13) comprising at least one finger or flange extending around the discharge tube (2) and configured to hold open an edge of the open end of the bag (B) while the discharge tube (2) is positioned inside the bag (B).20251908 WO EN

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