WO2018096518A1

WO2018096518A1 - Method and drum for moving rod-shaped articles of the tobacco industry

Info

Publication number: WO2018096518A1
Application number: PCT/IB2017/057432
Authority: WO
Inventors: Moreno ARBIZZANI; Massimo Sartoni; Luca Federici
Original assignee: G.D S.P.A.
Priority date: 2016-11-28
Filing date: 2017-11-28
Publication date: 2018-05-31
Also published as: IT201600120087A1; EP3544451B1; EP3544451A1; PL3544451T3

Abstract

A method for moving rod-shaped articles of the tobacco industry comprises the steps of: setting a drum provided with peripheral suction flutes in rotation about an axis of rotation; feeding a succession of rod- 5 shaped articles into respective suction flutes of the drum during the rotation of the drum, this step of feeding being carried out by a transverse movement of each article towards a respective suction flute along a direction perpendicular to the longitudinal axis of the suction flute; moving the articles axially along the longitudinal axis of the respective suction flute 10 during the rotation of the drum. Each suction flute has at least one suction slot to hold an article within the flute, the suction slot having a shape which is elongate along a direction perpendicular to the longitudinal axis (Y) of the flute (5), the steps of feeding the articles to the drum and axially moving the articles in the respective suction flutes being carried out in 15 such a way that each article is moved to and held in a position to completely cover at least one respective elongate slot.

Description

DESCRIPTION

METHOD AND DRUM FOR MOVING ROD-SHAPED ARTICLES OF THE

TOBACCO INDUSTRY

Technical field

This invention relates to a method and a drum for moving rod-shaped articles of the tobacco industry, where the articles may be filter segments, cigarette segments or whole cigarettes of single or double length.

More preferably, the invention applies to conveyor drums in filter tip attachment machines, where one or more segments of filter material and a cigarette segment are joined to together to obtain a filter-tipped cigarette.

More specifically, but without limiting the scope of the invention, the invention is applicable to centring drums in filter tip attachment machines, where two or more filter segments received from a preceding cutting drum are centred according to a predetermined arrangement along a respective suction flute.

Background art

It is known that in the field of cigarette production machines, the semi finished articles (filter or cigarette segments) and the finished cigarettes are transferred from one working station to another by drums which are externally provided with parallel flutes, of arcuate cross section and generally parallel to the axis of rotation of the drum, which receive the semi finished or finished articles.

The semi finished or finished articles are held within the flutes by pneumatic suction transmitted to each flute from the inside of the drum through one or more suction slots of circular cross section which give onto the bottom of the flute.

It has been found that in some circumstances, mainly when transferring very short segments, hence typically in filter tip attachment machines, a segment may not be positioned in such a way as to cover and close the entire suction slot, thus allowing suction to be discharged to the outside and resulting in a retaining effect which is not strong enough to hold the segment within the respective suction slot.

This problem occurs especially in the centring drums, located downstream of the respective cutting drums, where individual filter segments (generally having different properties) are made to translate axially in the respective suction slot until reaching a mutually juxtaposed configuration suitable for subsequent processes to be carried out. In effect, in this context, the risk of one or more suction slots remaining partly uncovered during the translating movement of the segments is high, thus cancelling or making ineffective the retaining action of the suction of the entire flute. Disclosure of the invention

In this context, the basic technical purpose of this invention is to provide a method and a drum for moving rod-shaped articles of the tobacco industry capable of overcoming the above mentioned disadvantages of the prior art.

More specifically, the aim of this invention is to provide a method and a drum for moving rod-shaped articles of the tobacco industry capable of achieving a high level of operating dependability, with reference in particular to use with segments of reduced length.

The technical purpose indicated and the aims specified are substantially achieved by a method and a drum for moving rod-shaped articles of the tobacco industry comprising the technical features described in one or more of the appended claims.

More specifically, the invention relates to a method for moving rod-shaped articles of the tobacco industry, comprising the following steps:

- preparing a drum having a succession of peripheral suction flutes disposed parallel to each other and one after the other;

- setting the drum in rotation about an axis of rotation so as to move each suction flute transversely to its longitudinal axis;

- feeding a succession of rod-shaped articles into respective suction flutes of the drum during the rotation of the drum, this step of feeding being carried out by a transverse movement of each article towards a respective suction flute along a direction perpendicular to the longitudinal axis of the suction flute;

- moving the articles axially along the longitudinal axis of the respective suction flute during the rotation of the drum.

Advantageously, each suction flute has at least one suction slot configured to hold an article within the suction flute and having a shape which is elongate along a direction perpendicular to the longitudinal axis of the flute.

In this configuration, the step of feeding the articles to the drum is carried out in such a way that the article is positioned to completely cover at least one respective elongate suction slot, while the step of moving the articles axially is carried out in such a way that each article is held in a position to completely cover the respective elongate suction slot during the axial movement.

It follows that the reduced axial dimension of the suction slot allows the article to be effectively held within the suction slot even while the article is being moved, without leaving the slot uncovered at any time during the axial movement of the article.

Preferably, the step of feeding the articles to the drum is carried out by feeding two or more articles, preferably simultaneously, into a respective suction flute in such a way that the articles are positioned inside the respective suction flute coaxially or substantially coaxially with each other. In this situation, the step of moving the articles axially is carried out by moving at least one of the articles along the suction flute during the rotation of the drum to vary the mutual distance between the articles positioned in the same suction flute.

Each of the two or more articles to be moved axially in the respective suction flute is fed to the suction flute in such a way as to completely cover a respective elongate suction slot and is subjected to axial movement along the suction slot in such a way that it is held in a position to completely cover the respective suction slot during the axial movement. That way, thanks to the elongate shape of the suction slots combined with their transverse orientation, the slots are never left uncovered during the axial movement of the articles, so that suction efficiency remains at an optimal level allowing the articles to be held properly within the respective suction flute.

In one embodiment, the step of feeding the articles to the drum is carried out by also feeding at least one intermediate segment between two other articles, and the step of feeding the articles is carried out by keeping the intermediate segment at a substantially fixed position along the respective suction flute during the rotation of the drum and moving the outer articles axially along the suction flute until they come into abutment against the intermediate segment.

Preferably, the intermediate segment is fed to the drum in such a way that the intermediate segment is held within the respective suction flute by at least one respective suction slot whose shape is elongate along a direction perpendicular to the longitudinal axis of the flute. More preferably, the intermediate segment is positioned to completely cover the respective suction slot.

In one preferred embodiment, the step of feeding the articles is carried out by a feed conveyor located downstream of the drum and tangent to the drum so it can transfer the articles along a direction perpendicular to the axis of extension of the articles. The tangent conveyor is preferably a feed drum or roller. Alternatively, it might also be a linear conveyor for transversely feeding a succession of articles. Brief description of the drawings

A preferred embodiment of the method described above and of a conveyor drum according the invention and particularly suitable for implementing the method are described below with reference to the accompanying drawings, which illustrate a non-limiting embodiment and in which:

- Figure 1 shows a sectional view of a drum according to this invention; - Figure 2 shows a view of the peripheral mantle of the drum of Figure 1 ;

- Figure 2A shows an enlarged view of a part of the mantle of Figure 2;

- Figures 3 and 4 show a portion of the drum of Figure 1 in two different, consecutive working configurations. Detailed description of preferred embodiments of the invention

The drum according to the invention, which is labelled 1 in its entirety and a cross section of which (showing only half of it, since the other half is identical) is illustrated in Figure 1 .

Figure 1 shows a centring drum of the tobacco industry in detail and the structure and function of the drum are described below. The invention, however, is equally applicable to other types of drums of the tobacco industry - for example, filter cutting drums, intercalating drums or simply drums for transferring the filters - preferably drums where one or more articles disposed on the drum are moved axially as the drum itself rotates. In its main features, the centring drum 1 is of known type and specifically comprises a main member 2 with a mantle 3 mounted radially on the exterior of it and with an intermediate member 2a interposed between the two.

The main member 2 is, for example, fixed and the mantle 3 rotates on it about the axis "X" of the drum, or the main member 2 and the mantle 3 are fixed to each other, together with the intermediate member 2a, and are rotatable about the axis "X" of the drum.

Formed on the outside surface of the main member 2 there are openings

4 which transmit a sucking action, by negative pneumatic pressure, from a zone inside the main member 2 to the mantle 3.

Figure 2 shows the mantle 3, which is furnished with a succession of flutes

5 for housing one or more rod-shaped articles (for example filters or filter segments, shown in Figures 3 and 4) or, alternatively, cigarette segments or cigarettes of single or multiple length.

Each flute is defined by a groove formed in the outside surface of the mantle 3 and extends along a respective longitudinal axis Ύ" to receive one or more rod-shaped articles, each disposed with its longitudinal axis aligned with the longitudinal axis Ύ" of the flute 5.

More specifically, in transverse cross section, the flutes 5 each have the shape of a circular arc and are substantially shaped to match a corresponding portion of one or more rod-shaped articles to be held therein.

Preferably, the flutes 5 are disposed with their longitudinal axes Ύ" parallel to the axis of rotation "X" of the drum 1 .

As may be seen in Figure 1 , the drum 1 also comprises centring units 6, only one of which is shown in Figure 1 , each of which is provided (according to a substantially known structure) with a pair of opposing arms 7, that is to say, disposed at mutually opposite positions along the axis "X" of the drum 1 , and having respective fingers 8 which are insertable into a respective flute 5 to press the articles housed therein and to move them close to each other according to a desired arrangement in a compact, centred configuration along the axis "X" of the drum 1 .

More precisely, the fingers 8 are deformable centring rings which centre the article by acting on the outermost part of it relative to the diameter of the drum. As shown in Figure 2, the mantle 3 comprises, for each flute 5, three suction slots 9 disposed on the bottom of the flute 5 and connectable to the source of negative pneumatic pressure by respective ducts 10 which are formed in the mantle 3 and which communicate with the openings 4 of the main member 2.

In variants not illustrated, or as a function of the type of drum to be made, there may be only one suction slot or a plurality of suction slots for each flute.

According to one advantageous aspect of the invention, at least some of the slots 9 are elongate in shape along a direction perpendicular to the longitudinal axis Ύ" of the flute 5, specifically along a direction which is substantially tangential with reference to the rotation of the mantle 3.

It should be considered that since the flutes 5 have an arcuate transverse cross section, the suction slots 9 do not lie exactly on a flat surface and this will be taken into account as this description continues.

As may be seen in Figure 2 and in the enlarged view of Figure 2A, the suction slots 9 are arranged along a plurality of circumferential lines around the axis of rotation "X" of the drum. Along at least one of the lines, there is at least one suction slot 9 in each flute 5.

Preferably, all the suction slots 9 of at least one of the lines have the aforementioned elongate shape and, still more preferably, all the suction slots 9 are elongate in shape.

More in detail, the suction slots 9 having the elongate shape are disposed along a first and a second circumferential line "L1 , L2" (Figures 3 and 4), aligned with each other around the axis of rotation "X" of the drum 1 , and also along a third and a fourth circumferential line "L3, L4", alternately aligned with each other, the third and fourth lines "L3, L4" being disposed at positions axially offset from the first and second lines "L1 , L2", in particular on the same side thereof. In other words, the first and second circumferential lines "L1 , L2" define a first block of suction slots 9, while the third and fourth circumferential lines "L3, L4" define a second block of suction slots 9, where the first block is axially offset from the second block. Preferably, along each third and fourth line "L3, L4", each flute 5 provided with a suction slot 9 is alternated with a flute without the suction slot 9. Suction slots 9 distributed in this way are a characteristic feature of a centring drum, whose operation is summarized in Figures 3 and 4.

Figure 3 represents a first operating step in which the drum 1 receives groups of rod-shaped articles 100, 200, 300 which are axially spaced from each other (the first and second articles 100, 200 are, in the example illustrated, combined to define a single article of greater length). More specifically, two consecutive flutes 5 of the drum 1 receive the groups of articles 100, 200, 300 in two different configurations - for example, with the third article 300 axially offset from the preceding one. In this configuration, the suction slots 9 are distributed in the two flutes 5 in such a way that each article 100, 200, 300 completely covers at least one suction slot 9, thus being held correctly in the flute 5 by negative pneumatic pressure.

Figure 4 represents a second operating step, following the first upon completion of the combining action applied by the centring units 6. More in detail, between receiving the groups of articles 100, 200, 300 (at an infeed station, not illustrated) and their subsequent delivery to a further transfer drum or other part responsible for picking them up (at an outfeed station, not illustrated), the centring units 6 (during the continuing rotation of the drum 1 ) are moved closer together in such a way that the respective fingers 8 come into contact with the end articles 100, 300 until the articles 100, 200, 300 are combined in a configuration where each article 100, 200, 300 is positioned to completely cover at least one respective slot 9 (which might even be different from the suction slot 9 which the article covered previously, when it was received). The invention is optimally applicable to rod-shaped articles. In effect, such segments, when fed to the drum 1 , are correctly retained by at least one respective suction slot 9 and, preferably also during their axial translation under the action of the centring units 6, continue to cover a single suction slot 9.

Advantageously, the invention allows improving the action by which the articles, more specifically articles of reduced axial dimensions, are retained and, still more specifically, in situations where the articles are moved axially along a respective suction flute.

Claims

1 . A method for moving rod-shaped articles of the tobacco industry, comprising the following steps:

- preparing a drum (1 ) having a succession of peripheral suction flutes (5) disposed parallel to each other and one after the other, each suction flute (5) extending along a respective longitudinal axis (Y);

- setting the drum (1 ) in rotation about an axis of rotation (X) so as to move each suction flute (5) transversely to the respective longitudinal axis

00;

- feeding a succession of rod-shaped articles (100, 200, 300) into respective suction flutes (5) of the drum (1 ) during the rotation of the drum

(1 ), this step of feeding being carried out by a transverse movement of each article (100, 200, 300) towards a respective suction flute (5) along a direction perpendicular to the longitudinal axis (Y) of the suction flute (5);

- moving the articles (100, 200, 300) axially in the respective suction flute (5) along the longitudinal axis (Y) during the rotation of the drum (1 );

characterized in that:

- each suction flute (5) has at least one suction slot (9) to hold an article (100, 200, 300) within the suction flute (5), the suction slot (9) having a shape which is elongate along a direction perpendicular to the longitudinal axis (Y) of the flute (5),

- the step of feeding the articles (100, 200, 300) to the drum (1 ) is carried out in such a way that each article (100, 200, 300) is positioned to completely cover at least one respective elongate suction slot (9), and

- the step of moving the articles (100, 200, 300) axially is carried out in such a way that each article (100, 200, 300) is held in a position to completely cover the respective elongate suction slot (9) during the axial movement of the article (100, 200, 300).

2. The method according to claim 1 , wherein the step of feeding the articles (100, 200, 300) to the drum (1 ) is carried out by feeding two or more articles (100, 200, 300), preferably simultaneously, into a respective suction flute (5) in such a way that the articles (100, 200, 300) are positioned inside the respective suction flute (5) coaxially or substantially coaxially with each other, and wherein the step of moving the articles (100, 200, 300) axially is carried out by moving at least one of the articles (100, 200, 300) along the suction flute (5) during the rotation of the drum (1 ) to vary the mutual distance between the articles (100, 200, 300) positioned in the same suction flute (5).

3. The method according to claim 2, wherein each of the two or more articles (100, 200, 300) to be moved axially in the respective suction flute (5) is fed to the suction flute (5) in such a way as to completely cover a respective elongate suction slot (9) and is subjected to axial movement along the suction slot (5) in such a way that it is held in a position to completely cover the respective suction slot (9) during the axial movement of the article (100, 200, 300).

4. The method according to claim 2 or 3, wherein the step of feeding the articles (100, 200, 300) to the drum (1 ) is carried out by also feeding at least one intermediate article (200) between two outer articles (100, 300), and wherein the step of feeding the articles (100, 200, 300) is carried out by keeping the intermediate article (200) at a substantially fixed position along the respective suction flute (5) during the rotation of the drum (1 ) and moving the outer articles (100, 300) axially along the suction flute (5) until they come into abutment against the intermediate article (200).

5. The method according to claim 4, wherein the intermediate article (200) is fed to the drum (1 ) in such a way that the intermediate article (200) is held within the respective suction flute (5) by at least one respective suction slot (9) whose shape is elongate along a direction perpendicular to the longitudinal axis (Y) of the flute (5), the intermediate article (200) being positioned to completely cover the at least one respective suction slot (9).

6. The method according to one or more of the preceding claims, wherein the step of feeding the articles (100, 200, 300) is carried out by a feed conveyor located downstream of the drum (1 ) and tangent to the drum (1 ) so it can transfer the articles (100, 200, 300) along a direction perpendicular to the axis of extension of the articles (100, 200, 300).

7. A conveyor drum for tobacco industry machines, configured in particular to implement the method according to one or more of the preceding claims, comprising a peripheral mantle (3) rotatable about an axis of rotation (X) and provided with a succession of flutes (5) for housing one or more rod-shaped articles (100, 200, 300), wherein each flute (5) extends along its longitudinal axis (Y) to receive one or more rod-shaped articles (100, 200, 300) positioned with their longitudinal axes aligned with the longitudinal axis (Y) of the flute (5), the mantle (3) comprising, for each flute (5), one or more suction slots (9) formed in the flute (5) and connectable to a source of negative pneumatic pressure, characterized in that at least some of the suction slots (9) have an elongate shape along a direction perpendicular to the longitudinal axis (Y) of the flute (5).

8. The drum according to claim 7, wherein the suction slots (9) are disposed along a plurality of circumferential lines (L1 ... L4) around the axis of rotation (X), and wherein all the suction slots (9) of at least one of the lines (L1 ... L4) have the elongate shape.

9. The drum according to claim 7 or 8, wherein all the suction slots (9) have the elongate shape.

10. The drum according to any one of claims 7 to 9, wherein the suction slots (9) extend along an arcuate profile defined by the respective suction flute (5) and extend around a respective axis parallel or coinciding with the longitudinal axis (Y) of the respective suction flute (5), each suction slot (9) having a dimension which, along the longitudinal axis (Y), is less than the dimension of the suction slot (9) along the arcuate profile.

1 1 . The drum according to any one of claims 7 to 10, in particular a centring drum, wherein the suction slots (9) having the elongate shape are disposed along a first and a second circumferential line (L1 , L2), alongside each other and disposed around the axis of rotation (X) of the drum (1 ), and also alternately along a third and a fourth circumferential line (L3, L4), the third and fourth lines (L3, L4) being disposed in a position axially offset from the first and second lines (L1 , L2).

12. A machine for the tobacco industry, in particular a filter tip attachment machine, comprising at least one conveyor drum (1 ) according to any one of claims 7 to 1 1 .