Device and method for moving tubular bodies

A device for moving tubular bodies, includes a conveyor belt for feeding a plurality of tubular pieces, each extending along a respective axis of extension, in such a way as to provide a succession of groups of tubular pieces where each group is defined by a predetermined number of tubular pieces positioned in succession along the respective axis of extension and transversely offset therefrom. The device includes at least one housing for containing at least one tubular piece inside of which an air cushion is produced by which the tubular piece is transferred translationally outside the housing along its respective axis of extension.

This application is the National Phase of International Application PCT/IB2016/056090 filed Oct. 12, 2016 which designated the U.S.

This application claims priority to Italian Patent Application No. 102015000062964 filed Oct. 19, 2015.

TECHNICAL FIELD

This invention relates to a device and a method for moving tubular bodies, made preferably of paper, paperboard, cardboard or plastic material.

Preferably, such tubular bodies define a component of a smokable article, for example a cigarette, and in particular, such tubular components are assembled to portions of a cigarette filter to make composite filters.

This invention is thus applicable in particular in the tobacco industry and, more specifically, in the construction of machines for making composite filters (filter makers or combiners) or cigarette holders.

BACKGROUND ART

Known in the prior art are systems for moving filters or pieces of “solid” filter, that is to say, cylindrical bodies made of filter material and thus defining a resistance to axial fluid flow.

In light of this, known devices can be broadly divided into two types, both based on the use of a pneumatic action, in one case as an active component in the movement of the filter pieces and, in the other case, as a retaining component.

In effect, a first prior art technique involves cutting the filter into a plurality of coaxial pieces, offsetting them by means of an offsetting drum and then applying suction to the filter pieces along the axial direction in such a way as to place them side by side to form an ordered sequence.

Alternatively, the pieces are offset and positioned on suction plates which hold each piece and move it translationally.

Disadvantageously, such methods cannot be used in the production of filters or cigarette holders and, more specifically, for the movement of the tubular elements constituting the above mentioned tubular bodies.

In effect, the low resistance offered by the thin side walls of the tubular filter pieces would cause them to be damaged/deformed when suction is applied to them.

Besides, the tubular shape makes suction along the axial direction totally useless.

DISCLOSURE OF THE INVENTION

This invention therefore has for an aim to provide a device and a method for moving tubular bodies to overcome the disadvantages described above with reference to the prior art.

More specifically, the aim of this invention is to provide a device and a method for moving tubular bodies which allow the tubular bodies to be aligned efficiently and without damaging them.

These aims are achieved by a device for moving tubular bodies having the features of one or more of the appended claims from1to13, as well as by a method for moving tubular bodies according to claims14and15.

More specifically, the device for moving tubular bodies, comprises feeding means for feeding a plurality of tubular pieces, each extending along a respective axis of extension, where the feeding means are configured in such a way as to provide a succession of groups of tubular pieces where each group is defined by a predetermined number of tubular pieces positioned in succession along the respective axis of extension and transversely offset therefrom, and at least one offsetting means configured to translationally move the tubular pieces of each tubular element in such a way as to dealign the respective axes of extension.

According to one aspect of the invention, the translational transfer means is provided with at least one housing for containing at least one tubular piece placed therein and with blowing means operating inside the housing and configured to produce an air cushion by which the tubular piece is transferred translationally outside the housing along its respective axis of extension.

Advantageously, thanks to this solution, moving the tubular piece is immediate and non-invasive.

In particular, it should be noted that the term “air cushion” is used to mean that at least one surface for supporting the tubular body in the housing has a directed flow of air passing through it to eliminate friction and translationally move the tubular piece.

More precisely, in one preferred embodiment, the blowing means comprise at least one outlet opening associated with a side wall of the housing to produce an air flow which is transverse to the tubular piece (externally thereof), thus forming the air cushion.

Preferably, there are at least two outlet openings, located on opposite sides of the housing (and hence, of the tubular piece).

Advantageously, therefore, the tubular piece does not touch any surface during its axial movement and thus does not risk being damaged.

This is clearly a factor of critical importance in the sector in which the device according to this invention is applied.

In effect, the device is preferably mounted in a machine for making smokable articles, in particular in the unit for making the composite filters, or in a machine for making tubes to be used in later stages of the process when the tubular bodies are used and where preventing damage to the product is extremely important.

In this regard, the feeding means preferably comprise:supply means for delivering a plurality of elongate tubular elements extending along a respective main axis and each having a predetermined length “L”;a cutting unit operatively located downstream of the supply means to receive the tubular elements in succession and configured to divide each tubular element into a plurality of tubular pieces of predetermined length “I” less than the predetermined length “L” of the tubular element and each extending along a respective axis of extension; and.an offsetting means configured to translationally transfer the tubular pieces of each tubular element in such a way as to dealign the respective axes of extension to make the groups of pieces.

With reference to the accompanying drawings, the numeral1denotes a device for moving tubular bodies, made preferably of paper, paperboard, cardboard or plastic material.

Preferably, the tubular bodies define a portion of a composite filter for smokable articles, in particular cigarettes or cigarette holders.

Thus, the movement device1is preferably applicable in a machine for making smokable articles and in particular, in a unit, denoted by the numeral100in the accompanying drawings, for making filters, cigarette holders or composite filters.

The device1is thus used for moving tubular bodies, preferably made of paper, paperboard, cardboard or plastic material and having limited thickness and grammage (for example, 90-130 g, in particular 110 g).

The device1comprises supply means2for delivering a plurality of elongate tubular elements “T” extending along a respective main axis “A” and each having a predetermined length “L”.

The tubular elements “T” have the same diameter as the bodies to be moved and, preferably, a length which is a multiple of the length of the bodies.

Preferably, the supply means2comprise a conveyor belt2aand/or a hopper2b.

In the embodiment illustrated, the conveyor belt2ais movable along its operating direction in such a way as to move the tubular elements “T” transversely, that is, at right angles, to the respective main axis “A”.

The hopper2bis preferably located immediately downstream of the conveyor belt2a, in particular, of a free end thereof, to receive the tubular elements “T” (by gravity).

The device1also comprises a cutting unit3operatively located downstream of the supply means2to receive the tubular elements “T” in succession.

The cutting unit3is configured to divide each tubular element “T” into a plurality of tubular pieces “F” of predetermined length “I” and each extending along a respective axis of extension “B” (parallel to the main axis “A”).

The length “I” is smaller than the predetermined length “L” of the tubular element “T”. More precisely, the length “I” of the tubular piece “F” is a submultiple of the length “L” of the tubular element “T”.

The cutting unit3preferably comprises a drum3arotatable about a respective axis of rotation (parallel to the main axis “A” of the tubular elements “T”) and provided with a plurality of peripheral grooves for receiving the tubular elements “T”.

Also, cutting means3bare provided to act on the periphery of the drum3a, in particular at the grooves, to divide the tubular elements “T” into respective pluralities of pieces “F”.

The cutting means3bmay be of a mechanical type (cutting blades or the like) or optical (e.g. laser cutters).

Preferably, therefore, the cutting unit3is configured to receive a sequence of tubular elements “T” and to deliver (after cutting) a sequence of groups of pieces “F”, where each group is defined by a predetermined number of tubular pieces “F” (equal in number to the ratio between the length “L” and the length “I”) aligned coaxially along the respective axes of extension “B”.

In light of this, the device1also comprises at least one offsetting means4configured to translationally transfer the tubular pieces “F” made from each tubular element “T” in such a way as to dealign the respective axes of extension “B”.

More precisely, the offsetting means4is configured to translationally move all, or some, of the pieces “F” of each group along a direction transverse, preferably at right angles, to the axis of extension “B”.

In the preferred embodiment, the offsetting means4also comprises a rotary drum4aoperatively located downstream of the cutting unit3and preferably tangent to the drum3aof the cutting unit3.

The pieces are moved by means of flutes which are misaligned with each other (but fixed relative to one another) or using circumferentially movable grooves or pockets to dealign the pieces “F”.

In other words, in the first embodiment, the offsetting means does not actively move the pieces “F” but “picks” them with a delay one from another in such a way as to dealign them.

Alternatively, in the second embodiment, the offsetting means4actively moves the pieces using specific movement means.

It should be noted that, preferably, all or some of the devices described up to now (supply means2, cutting unit3and offsetting means4) define feeding means5for feeding a plurality of the tubular pieces “F” and configured to provide a sequence of groups of tubular pieces “F” defined (that is, each group is defined) by a predetermined number of tubular pieces “F” positioned in succession along their axes of extension “B” and offset transversely to that direction of extension “B”.

Operatively downstream of the offsetting unit4, the device1comprises at least one translational transfer means6configured to move the pieces “F” along the respective axis of extension “B” to juxtapose them and define an ordered succession of pieces “F”.

This ordered succession thus extends transversely, preferably at right angles, to the axes of extension of the pieces “F” themselves, which are placed in a substantially juxtaposed parallel relationship.

In light of this, the offsetting means4and the translational transfer means6jointly define an alignment unit7located operatively downstream of the cutting unit3and configured to translationally move the tubular pieces “F” from a first configuration, where the pieces “F” of each unit are aligned with each other along their axes of extension “B” to a second configuration, where the pieces “F” are juxtaposed with their axes of extension “B” substantially parallel.

According to one aspect of this invention, the translational transfer means6is provided with at least one housing8for containing at least one tubular piece “F” and with blowing means9operating inside the housing8.

The blowing means9are configured to produce an air cushion by which the tubular piece “F” is transferred translationally outside the housing8along its respective axis of extension “B”.

Advantageously, thanks to this solution, moving the tubular piece “F” is immediate and non-invasive.

In effect, that way, the tubular piece does not touch any surface during its axial movement and thus does not risk being damaged.

Preferably, the housing8extends along a central axis “C” corresponding to the axis of extension “B” of the respective tubular piece “F”.

Further, the housing8is delimited by at least one side wall8aplaced radially to the central axis “C”.

Thus, the side wall at least partly surrounds the central axis “C”, preventing the pieces “F” in the housing8from moving transversely to the central axis “C” (or limiting such movement).

Also, to allow the piece “F” to come out, the housing8is provided with at least one opening11. The opening11is thus located along the central axis “C”.

In other words, the opening11is defined by a transverse cross section “C” and is located at one end of the housing8.

In this regard, the translational transfer device6comprises at least one receiving zone12, or receiving chamber12, which can face the opening11to receive the tubular piece “F” translationally transferred by the blowing means9.

Thus, the receiving chamber12is adjacent to the opening11and extends along the central axis “C” of the housing8(in practice defining an extension thereof).

Preferably, the blowing means9is connected to an air source and includes at least one outlet opening9a,9bassociated with the side wall8ato generate an air flow transverse to the tubular piece “F”, thus defining the air cushion.

In particular, it should be noted that the blowing means9, which (in an embodiment not illustrated) might also be a sequence of holes, are configured to blow from the at least one outlet opening9a,9ba flow of air “N” inclined relative to the central axis “C” of the housing8and having at least one component which is tangential to the central axis “C”.

In other words, the air flow “N” (at least partly defining the air cushion) is directed in the same direction as the movement of the piece “F” and is inclined to the central axis “C”.

The inclination is defined by angles β of between 5° and 75°, preferably between 15° and 45° and more preferably around 30°.

Structurally, the blowing means9have at least one duct10leading to the at least one outlet opening9a,9band having an end stretch10athat is inclined at a predetermined angle to the central axis “C” of the housing8.

Preferably, the angle of inclination corresponds to (or coincides with) that of the air flow “N” (more precisely, determines it).

Thus, the end stretch10ais inclined to the central axis “C” of the housing8at an angle α of between 5° and 75°, preferably between 15° and 45° and still more preferably, is approximately 30°.

In the preferred embodiment, the translational transfer means6comprises a rotary drum13; the drum13is provided, on its periphery, with a plurality of angularly spaced flutes13afor receiving at least one tubular piece “F” each.

It should be noted that the flutes run parallel to an axis of rotation of the drum13.

The translational transfer means6also comprises at least one covering element14extending circumferentially at least partly around the drum13in such a way as to radially delimit each flute13ait is facing.

Thus, in conjunction with the covering element14, each flute13adefines the at least one housing8.

More precisely, the covering element14defines a portion of the side wall8aof the housing8distal from the axis of rotation of the drum13.

It should be noted that the drum13is rotatable, while the covering element14is fixed.

Thus, the housing is defined by a flute13aand the respective portion of covering element14under which the flute13aitself passes.

It should be noted that, preferably and according to the embodiment illustrated, the translation transfer means6comprises a plurality of housings8(angularly) spaced from each other and each defined by one flute13aand by a respective portion (which varies during rotation) of the covering element14.

In some embodiments, the rotary drum might be replaced with a translating element (for example a conveyor belt), in which case the flutes would be spaced only axially and not angularly.

Preferably, the blowing means9have at least one proximal outlet opening9awhich is proximal to the axis of rotation of the drum13and made at each flute13a.

More precisely, the proximal outlet opening9ais made on a base15which supports the piece “F” inside the flute13a.

The proximal outlet opening9apreferably possesses the features described above in connection with a generic “outlet opening”.

Moreover, the blowing means9preferably have a plurality of proximal outlet openings9alocated in succession along the central axis “C” of the housing and spaced from each other.

In the preferred embodiment, the blowing means9have at least one distal outlet opening9bwhich is distal from the axis of rotation of the drum13and made at the covering element14.

The distal outlet opening9b, too, preferably possesses the features described above in connection with a generic “outlet opening”.

Preferably, with reference for example toFIG.3, the distal outlet opening9bis elongate in shape and extends circumferentially around the drum13.

In other words, the distal outlet opening9bis defined by an elongate slot16running along the covering element14and at least partly surrounding the drum in such a way as to continue acting on the piece “F” while the drum13rotates.

In this regard, it should be noted that the covering element14extends between a first circumferential edge14aand a second circumferential edge14b; the distal outlet opening9b(that is, the slot16) in turn extends elongately between a first end16a, proximal to the first edge14a, and a second end16b, proximal to the second edge14b.

Thus, the distal outlet opening9bextends in a direction inclined to a circumferential axis surrounding the drum13.

Moreover, the blowing means9preferably have a plurality of distal outlet openings9blocated in succession along the central axis “C” of the housing and spaced from each other.

Advantageously, this guarantees uniform action for the full distance travelled by the tubular piece “F”.

Also an object of this invention is the method for moving the tubular bodies (that is, tubular pieces) which is preferably but not exclusively implemented by the device of this invention.

The method comprises preparing at least one elongate tubular element “T” extending along a respective main axis “A” and having a predetermined length “L” and then dividing it into a plurality of coaxial tubular pieces “F” arranged in succession along the main axis “A”.

Next, or at the same time, the tubular pieces “F” are offset by translationally transferring all or some of them along a direction transverse to the main axis “A”.

Thus, the pieces “F” are moved from a first configuration, where they are aligned along the main axis “A”, to a second, intermediate configuration, where they are still arranged in succession but where their respective axes “B” are dealigned.

In light of this, the method in effect comprises translationally transferring all or some of the tubular pieces “F” along the main axis “A” so as to juxtapose them to define an ordered succession of pieces “F” extending transversely (that as at right angles) to the main axis “A”.

According to one aspect of the invention, the translational transfer step is performed by means of a blowing action on an outside face of a side wall of the tubular pieces “F” to produce an air cushion capable of translationally transferring them.

In particular, the blowing action is oriented, that is, directed, in such a way as to impart a movement to the pieces.

Preferably, therefore, the blowing action is performed by directing the air flow at an inclination at least partly concordant with a direction of translation of the tubular piece “F”, thus making it possible to simultaneously produce the air cushion and the translational movement.

In other words, the blown air produces both a lifting and a forward pushing action.

The invention achieves the above mentioned aims and brings important advantages.

In effect, the pneumatic means, which are of a type already in existence and employed in similar machines and which are used to produce an air cushion on the piece, on the one hand allow rapid, precise movement of the piece and, on the other, are simple and inexpensive to make.

Moreover, the provision of distal outlet openings which are elongate in shape allows maximizing the forward pushing action applied to the tubular pieces and thus optimizes their movement.