MADE BY ADDITIVE MANUFACTURING . "

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims priority from Italian patent application no . 102020000029423 filed on December 2 , 2020 , the entire disclosure of which is incorporated herein by reference .

TECHNICAL FIELD

The present invention relates to an operating machine to process smoking articles , for example a packing machine for the production of packs of cigarettes , a manufacturing machine for the production of cigarettes or cigarette filters , or a filterinserting machine for applying filters to cigarettes .

PRIOR ART

An operating machine to proces s smoking articles comprises numerous components assembled together .

Some of these components in use are subj ected to relatively high mechanical stress , both as a result of the continuous accelerations to which they are subj ected due to the motion of the production line , and as a result of the processes that must be performed ( for example a cyclical cutting of a band by using a kni fe that impacts against an anvil ) .

The components that in use are subj ected to relatively high mechanical stress must be designed and si zed both to be able to withstand said mechanical stress , and to be manufactured by casting in a mould and possibly subsequent mechanical processing with chip removal ; consequently, said components are generally quite heavy ( as they are inevitably " solid" , namely, with a limited number of inner cavities ) and therefore require highly performing electric motors for their movement ( therefore more bulky, more expensive and with greater energy-consumption) .

Patent application DE102019101301A1 describes a suction drum for a unit for labelling containers .

Patent application DE102019203418A1 describes a labelling device for containers , in particular bottles , having a cutting device for cutting labels from a strip of labels .

DESCRIPTION OF THE INVENTION

The obj ect of the present invention is to overcome the aforementioned drawbacks , namely to provide an operating machine to process smoking articles which is free from the drawbacks described above .

Said obj ect is achieved by proposing an operating machine to process smoking articles according to the attached claims .

The claims describe preferred embodiments of the present invention forming an integral part of the present description .

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described with reference to the attached drawings , which illustrate some non-limiting embodiments thereof , wherein :

• Figure 1 is a schematic and perspective view of a packing machine made according to the present invention;

• Figure 2 is a perspective , and schematic view with parts removed for clarity of part of the packing machine of Figure 1 ;

• Figure 3 is a front perspective view of a folding spindle of the packing machine of Figure 1 ;

• Figure 4 is a rear perspective view of the folding spindle of Figure 4 ;

• Figure 5 is a perspective view of a sucking holding head of the filter-inserting machine of Figure 1 ;

• Figure 6 is a further perspective view of the sucking holding head of Figure 5 ;

• Figure 7 is a plan view of the sucking holding head of Figure 5 ;

• Figure 8 is a section view along the line VI I I-VI I I of the sucking holding head of Figure 5 ;

• Figure 9 is a perspective view of a sucking pocket of a wrapping drum of the packing machine of Figure 1 ;

• Figure 10 is a plan view of the sucking pocket of Figure

9 ;

Figures 11 and 12 are two sectional views along lines XI - XI and XI I-XI I of the sucking pocket of Figure 9 ;

• Figure 13 is a front perspective view of a cutting drum of the packing machine of Figure 1 ; and

• Figure 14 is a rear perspective view of the cutting drum of Figure 13 .

PREFERRED EMBODIMENTS OF THE INVENTION

With reference to Figure 1 , number 1 denotes as a whole a packing machine which is designed to manufacture a rigid pack of cigarettes with a hinged lid and which operates with intermittent motion (namely, a motion that provides for a cyclical alternation of motion and stopping steps ) .

The packing machine 1 comprises a forming unit A in which the groups 2 of cigarettes are formed subsequently, a wrapping unit B in which a respective wrapping sheet 3 ( illustrated in Figure 2 ) is wrapped around each group 2 of cigarettes ( illustrated in Figure 2 ) so as to form an inner wrap 4 ( illustrated in Figure 2 ) , and a wrapping unit C in which a collar and a blank are wrapped around each inner wrap 4 so as to form an outer container provided with a lid .

The forming unit A to form the groups 2 of cigarettes comprises a hopper 5 provided with three outlets to simultaneously feed three groups 2 of cigarettes to three respective pockets of a forming conveyor that supports a plurality of pockets .

The wrapping unit B comprises a wrapping conveyor 6 designed to move each group 2 of cigarettes along a straight and hori zontal wrapping path P . In particular, the wrapping path P extends through a feeding station S I in which each group 2 of cigarettes is coupled to a corresponding wrapping sheet 3 that folds in a "U" shape around the group 2 of cigarettes .

The packing machine 1 comprises a feeding device 7 which cyclically feeds the wrapping sheets 3 into the feeding station S I , namely arranges each wrapping sheet 3 in the feeding station S I so that the wrapping sheet 3 is intercepted by a corresponding group 2 of cigarettes moving along the wrapping path . The feeding device 7 comprises an unwinding station in which a wrapping material band 8 i s unwound from a reel 9 and is moved towards a cutting device 10 which is arranged above the feeding station S I and cyclically performs a cross cut of the wrapping material band 8 to separate the single wrapping sheets 3 from the wrapping material band 8 .

The packing machine 1 comprises a wrapping drum 11 which supports a plurality of pockets 12 ( one of which is illustrated in Figure 9 ) each designed to contain an inner wrap 4 and a collar, and is rotatably mounted (with intermittent motion, namely "in a stepwi se manner") around a parallel hori zontal rotation axis . Each pocket 12 of the wrapping drum 11 receives a collar in a feeding station S2 , then receives an inner wrap 4 in a trans fer station S3 , subsequently receives a blank in a feeding station S4 , and releases the inner wrap 4 , the collar and the blank together in a trans fer station S5 .

The packing machine 1 comprises a feeding device 13 which cyclically feeds the collars into the feeding station S2 , namely arranges each collar in front of a pocket 12 . In the embodiment illustrated in Figure 1 , the feeding device 13 separates the collars from a continuous band by means of a cross cut ; alternatively, the feeding device 13 could feed the collars from the hopper .

The packing machine 1 comprises a feeding drum 14 which supports a plurality of sucking holding heads (not illustrated) each designed to hold a corresponding blank, and is rotatably mounted (with intermittent motion, namely "in a stepwi se manner") around a hori zontal rotation axis so as to move each sucking holding head along a circular feeding path .

Finally, the packing machine 1 comprises a wrapping drum 15 which is arranged downstream of the wrapping drum 11 , supports a plurality of pockets each designed to contain an inner wrap 4 , a collar and a blank ( received by the wrapping drum 11 in the trans fer station S5 ) , and is mounted to rotate (with intermittent motion, namely "in a stepwi se manner" ) around a hori zontal rotation axis .

As illustrated in Figure 2 , the feeding device 7 comprises two folding spindles 16 which are supported by a movement drum 17 that cyclically moves each folding spindle 16 between a receiving station S 6 , in which each wrapping sheet 3 is coupled to the folding spindle 16 , and the feeding station S I at the wrapping path P and in which the wrapping sheet 3 is coupled to a group 2 of cigarettes which, by moving along the wrapping path P, intercepts the wrapping sheet 2 that folds in a "U" shape around the group 3 of cigarettes .

The two folding spindles 16 are arranged at 180 ° relative to one another ( i . e . , they are symmetrically arranged around the rotation axis ) and therefore at each cycle the movement drum 17 performs a rotation of 180 ° .

Each folding spindle 16 has a central passage channel 18 through which a corresponding group 3 of cigarettes passes in the feeding station S I ; in other words , in the feeding station S I the central passage channel 18 of each folding spindle 16 is aligned with the wrapping path P and is crossed by a corresponding group 3 of cigarettes which moves along the wrapping path P pushed by the wrapping conveyor 6 . Furthermore , each folding spindle 16 has an outer surface 19 which is arranged around the central passage channel 18 and is designed to receive and hold the wrapping sheet 3 ; in other words , in each folding spindle 16 the outer surface 19 is crossed by the central passage channel 18 . In particular, the outer surface 19 of each folding spindle 16 is "U"-shaped and is formed by an outer wall 20 , by an inner wall 21 which is integral with a central hub of the movement drum 17 , and by a connecting wall 22 which is interposed between the outer wall 20 and the inner wall 21 , is perpendicular to the wrapping path P, and in which the passage opening 18 is formed . In each folding spindle 16 , the two walls 20 and 21 are " open" relative to the connecting wall 22 , namely, the two walls 20 and 21 form an obtuse angle with the connecting wall 22 ( therefore greater than 90 ° ) , preferably comprised between 95 ° and 140 ° ( in the embodiment il lustrated in the attached figures the angle is about 120 ° ) .

The outer surface 19 of each folding spindle 16 has a through slot 23 which is oriented parallel to the rotation axis ( and therefore parallel to the wrapping path P ) and through which a supporting column of a pusher of the wrapping conveyor 6 is designed to pass when the folding spindle 16 is in the feeding station SI.

According to a preferred but not binding embodiment, each folding spindle 16 comprises sucking means for holding the wrapping sheet 3 in contact with the outer surface 19 between the receiving station S6 and the feeding station SI; in other words, a plurality of suction holes 24 (illustrated in Figure 3) open on the outer surface 19, which are connected to a suction source and generate suction to hold the wrapping sheet 3 in contact with the said outer surface 19.

For a detailed description of the operation of the feeding device 41, we refer to what is described in patent application EP3725690A1 .

Figures 3 and 4 illustrate an alternative of the folding spindle 16 designed to operate with a double-line packing machine 1, but apart from the duplication, the folding spindle 16 illustrated in Figures 3 and 4 is completely similar to the folding spindle 16 illustrated in Figure 2.

As illustrated in Figures 3 and 4, the walls 20, 21 and 22 of the folding spindle 16 are formed by a single base element 25 (obviously U-shaped) from which, starting from an inner surface opposite to the outer surface 19, tubular ducts 26 extend (illustrated in Figure 4) which are empty on the inside to define, inside the same, suction passage channel. The base element 25 (having inside, a number of through openings to lighten the same) has the same thickness everywhere (that is, it has a uniform thickness along its entire extension) and is substantially a "sheet" (that is, the thickness of the same is much smaller than the other two dimensions) .

As previously stated, each folding spindle 16 is provided with a plurality of suction holes 24 (illustrated in Figure 3) , which lead through the outer surface 19 and are connected to respective terminal ends of the tubular ducts 26. Furthermore, parallelepiped-shaped ribs 27 (illustrated in Figure 4) , which are solid on the inside, project from the flat base element 25, starting from the inner surface, engage with the tubular ducts 26 and are interrupted at the tubular ducts 26. It is important to underline that the tubular ducts 26 not only have the function of " sucti on conveyors" which are passively supported by the base element 25 , but also perform an important structural function as they are actual reinforcing ribs of the base element 25 . In other words , the base element 25 alone would not be able to bear the mechanical stress to which, in use , is subj ected, since only the whole of the base element 25 with the tubular ducts 26 (which reinforce in a substantial way the base element 25 ) is able to bear the mechanical stress to which, in use , is subj ected . In other words , in the mechanical dimensioning of a folding spindle 16 the tubular ducts 26 perform an important function and therefore in use the tubular ducts 26 bear a signi ficant part of the mechanical stress to which the folding spindle 16 is subj ected .

The feeding device 13 compri ses a movable support (not illustrated) which supports a single sucking holding head 28 ( illustrated in Figures 5- 8 ) able to hold a corresponding collar ; in particular, the movable support cyclically moves the holding head 28 back and forth between a collar withdrawal station and a collar release station .

According to what is illustrated in Figures 5- 8 , each sucking holding head 28 comprises a cylindrical-shaped connection body 29 that is connected to the feeding drum (not illustrated) and a tubular duct 30 , which proj ects from a side surface of the connection body 29 , is perpendicular to a longitudinal axis of the connection body 29 and ends in two di f ferent holding portions 31 each provided with ( at least ) one suction hole 32 . In other words , in its final part each tubular duct 30 forks into two branches , each ending in a corresponding holding portion 31 . The two holding portions 31 of the same tubular duct 30 are arranged at a given distance from one another to engage respective portions of a collar so as to grip the collar in a safe and stable manner (namely, without the collar being left free to deform in an uncontrolled manner during the handling thereof ) . According to a di f ferent embodiment not illustrated, each tubular duct 30 ends only in a single holding portion 31 or ends in three- four holding portions 31 separated from one another . Each sucking holding head 28 comprises a flat reinforcement element 33 which is arranged next to the tubular duct 30 and is oriented radially (perpendicularly) relative to the tubular duct 30 , it connects to the tubular duct 30 at a centre line of the tubular duct 30 and proj ects from a side surface of the connection body 29 . As illustrated in the attached figures , in each holding head 28 , the reinforcement element 33 is initially arranged (namely, in a portion next to the connection body 29 ) on both sides of the tubular duct 30 and is subsequently arranged (namely, a portion away from the connection body 29 ) only on one side of the tubular duct 30 . Preferably, in each holding head 28 , the reinforcement element 33 has an outer edge 34 ( shown in Figure 6 ) which i s oriented perpendicularly to the reinforcement element 33 and gives greater sti f fness against bending .

It is important to underline that the tubular duct 30 not only has the function of " sucti on conveyor" , which is passively supported by the reinforcement element 33 , but also performs an important structural function being a real reinforcing rib of the base element 25 . In other words , the reinforcement element 33 alone would not be able to bear the mechanical stress to which, in use , is subj ected, since only the whole of the reinforcement element 33 with the tubular duct 30 (which reinforces in a substantial manner the reinforcement element 33 ) is able to bear the mechanical stress to which, in use , is subj ected . In other words , in the mechanical dimensioning of a holding head 28 , the tubular duct 30 performs an important function and therefore in use the tubular duct 30 bears a signi ficant part of the mechanical stress to which the holding head 28 is subj ected . Consequently, the tubular duct 30 is (partially) capable of sel f-supporting, namely, it also has an important structural function and is therefore not used only as a " sucti on conveyor" .

As illustrated in Figures 9- 12 , each pocket 12 of the wrapping drum 11 comprises a rectangular-shaped peripheral frame 35 , which is solid on the inside and delimits a cavity arranged at the centre . In other words , the peripheral frame 35 has a rectangular shape and extends in a ring-like manner around the cavity arranged at the centre . Each pocket 12 is a suction pocket and comprises a plurality of suction holes 36 which lead through an outer surface of the peripheral frame 35 and in use have the function of holding a corresponding collar, a corresponding blank, and a corresponding inner wrap 4 in the pocket 12 ; in particular, some suction holes 36 are exclusively dedicated to hold a corresponding collar, some suction holes 36 are exclusively dedicated to hold a corresponding blank, and some suction holes 36 are exclusively dedicated to hold an inner wrap 4 .

Furthermore , each pocket 12 compri ses a series of tubular ducts 37 ( illustrated in Figures 11 and 12 ) which terminate in the suction holes 36 and extend inside the peripheral frame 35 , namely, they are formed inside the hollow peripheral frame 35 avoiding depositing the material in corresponding tubular ducts 37 ; in particular, the tubular ducts 37 connected to the suction holes 36 dedicated exclusively to hold the collar, are separate and independent from the tubular ducts 37 connected to the suction holes 36 dedicated exclusively to hold the blank and from the tubular ducts 37 connected to the suction holes 36 dedicated exclusively to hold an inner wrap 4 .

As illustrated in Figures 13 and 14 , the cutting device 10 of the feeding device 7 comprises a cutting drum 38 which is rotatably mounted around a rotation axis 39 ; in use, the wrapping material band 8 winds around the cutting drum 38 and a kni fe (which cooperates with the cutting drum 38 ) performs a transversal cut of the wrapping material band 8 ( to separate a wrapping sheet 3 from the wrapping material band 8 ) while the wrapping material band 8 is wrapped around the cutting drum 38 . The cutting drum 38 comprises a hub 40 configured to be coupled to a shaft mounted so as to rotate around the rotation axis 39 , a rim 41 (namely, a peripheral skirt ) which is arranged around the hub 40 at a given distance from the hub 40 , and a plurality of spokes 42 which develop radially and connect the hub 40 to the rim 41 so that between the hub 40 and the rim 41 an empty space is provided . Each spoke 42 is formed by a plate arranged radially and centrally perforated to lighten the same (namely, provided with at least one through hole so as to reduce weight ) . According to a preferred embodiment illustrated in the attached figures , the hub 40 has an axial extension that is less than an axial extension of the rim 41 ; consequently, the spokes 42 have a trapezoidal shape , having to j oin the axially longer rim 41 to the axially shorter hub 40 .

The cutting drum 38 is provided with a plurality of sucking seats 43 , each designed to hold the wrapping material band 8 (before , during and after the transversal cut ) in contact with an outer surface of the rim 41 ; each sucking seat 43 is obtained in the rim 41 and has ( at least ) two suction holes 44 which are arranged at a given distance from one another and lead through an outer surface of the rim 41 . Therefore , in the rim 41 two annular rows (namely, two rings ) of suction holes 44 are provided, arranged at a given distance from one another .

The cutting drum 38 comprises , for each sucking seat 43 , a corresponding tubular duct 45 , which is fixed to an inner surface of the rim 41 opposite the outer surface , is arranged between two spokes 42 , and has a terminal end which is oriented radially and it is connected to the corresponding suction holes 44 . Furthermore , each tubular duct 45 has an initial end which is axially oriented and is obtained at an end ring 46 arranged perpendicular to the rim 41 . A pneumatic distributor (not illustrated) is laterally coupled to the end ring 46 , and which applies suction to the tubular ducts 45 ( or to the corresponding sucking seats 43 ) in the desired angular positions .

It is important to underline that the tubular ducts 45 not only have the function of " sucti on conveyors" , which are passively supported by the rim 41 , but also perform an important structural function being real reinforcing ribs of the rim 41 . In other words , the rim 41 alone may not be able to bear the mechanical stress to which, in use , it is subj ected, since only the assembly of the rim 41 with the tubular ducts 45 (which substantially reinforce the rim 41 ) is able to bear the mechanical stress to which, in use , it is subj ected . In other words , in the mechanical dimensioning of the rim 41 , the tubular ducts 45 perform an important function and therefore in use the tubular ducts 45 bear a significant part of the mechanical stress to which the rim 41 is subjected.

The pockets 12, the folding spindles 16, the holding heads 28, and the cutting drum 38 are examples of components of an operating machine to process smoking articles (in the nonlimiting embodiment illustrated in the attached figures, the packing machine 1) which are advantageously manufactured by means of additive manufacturing; namely, each component (pocket 12, folding spindle 16, holding head 28, or cutting drum 38) is one single monolithic piece, is formed by one single indivisible body manufactured as a seamless whole, and is manufactured by means of additive manufacturing.

Each component (pocket 12, folding spindle 16, holding head 28, or cutting drum 38) is made by additive manufacturing (also called 3D printing) , or by means of an industrial process that, starting from a digital 3D model, creates the piece by adding one layer on top of the other (some examples of technologies that can be used in additive manufacturing are stereolithography, Fused Deposition Modelling also called EDM, Selective Laser Sintering also called SLS, or Direct Laser Microfusion or DLM) .

According to a possible embodiment, each component (pocket 12, folding spindle 16, holding head 28, or cutting drum 38) is made entirely of a plastic material (plastic or resin) , namely, not of a metallic material (essentially to reduce production cost and weight) , as each component in use is not subjected to significant mechanical stress. Potentially the plastic material with which each component is made could be loaded (reinforced) with carbon or glass to increase the structural characteristics (for example Nylon 12CF is a carbon-f illed thermoplastic composite for 3D printing with excellent structural characteristics) .

According to a different embodiment, at least one component (pocket 12, folding spindle 16, holding head 28, or cutting drum 38) is made entirely of a metallic material. Generally, the folding spindle 16 , the holding head 28 and the cutting drum 38 are preferably made (by additive manufacturing) of a metallic material since in use they are subj ected to greater mechanical stress , while the pocket 12 is preferably made (by means of additive manufacturing) of a plastic material as it is subj ected, in use , to minor mechanical stress . Generally, the folding spindle 16 and the holding head 28 are made of aluminium while the cutting drum 38 is made of steel .

In the case of the folding spindles 16 , the use of additive manufacturing (which makes each folding spindle 16 a single undivided and indivisible body) allows to optimi ze the fluid dynamic ef ficiency of the tubular ducts 26 since the tubular ducts 26 can have irregular geometries chosen to optimi ze fluid dynamic ef ficiency (namely, without taking into account the construction and assembly problems that would arise i f additive manufacturing were not used) . In particular, the tubular ducts 26 not only have a highly advanced fluid-dynamic optimi zation, but , as previously mentioned, also have a structural function which allows to minimi ze the quantity of material necessary to manufacture a folding spindle 16 .

In the case of the holding heads 28 , the use of additive manufacturing (which makes each holding head 28 a single undivided and indivisible body) allows to optimi ze the fluid dynamic ef ficiency of the tubular duct 30 since the tubular duct 30 can have irregular geometries chosen to optimi ze fluid dynamic ef ficiency (namely, without taking into account the construction and assembly problems that would arise i f additive manufacturing were not used) . In particular, the tubular duct 30 not only has a highly advanced fluid-dynamic optimi zation, but , as previously mentioned, also has a structural function which allows to minimi ze the quantity of material necessary to manufacture a holding head 28 . A holding head 28 made by additive manufacturing as illustrated in the attached figures compared to a similar known holding head made without the use of additive manufacturing has : an equivalent sti f fness increased by twenty times , a rotational inertia reduced by three times (with a similar reduction of energy consumption) , a halved mass , and a production cost reduced by 40-50% .

In the case of the pockets 12 , the use of additive manufacturing (which makes each pocket 12 a single , undivided and indivisible body) allows the tubular ducts 37 to be created directly inside the peripheral frame 35 without the peripheral frame 35 having to be dismountable (namely, somehow openable ) . Therefore , it is no longer necessary for the peripheral frame 35 to be formed by several pieces j oined together and the tubular ducts 37 can have irregular geometries chosen solely to optimi ze fluid dynamic ef ficiency (namely, without taking into account construction and assembly problems that would arise i f additive manufacturing were not used) .

In the case of the cutting drum 38 , the use of additive manufacturing (which makes the cutting drum 38 a single undivided and indivisible body) allows the tubular ducts 45 to be created directly inside the rim 41 without the rim 41 having to be dismountable (namely, somehow openable ) . Therefore , it is no longer necessary for the rim 41 to be formed by several pieces j oined together and the tubular ducts 45 may have irregular geometries chosen to optimi ze the fluid dynamic ef ficiency (namely, without taking into account the construction and assembly problems that arise i f additive manufacturing were not used) . In particular, the tubular ducts 45 not only have a highly advanced fluid-dynamic optimi zation, but , as previously mentioned, also have a structural function which allows to minimi ze the amount of material necessary to manufacture the cutting drum 38 .

The reduction of the overall mass of the cutting drum 38 also allows to increase the quality of the processing (namely, of the transversal cutting) , since the reduced inertia of the cutting drum 38 allows the cutting drum 38 to exactly copy the law of motion of the wrapping material band 8 allowing to always have a correct positioning between the cutting drum 8 and the wrapping material band 8 to the full advantage of the precision of the transversal cut .

The packing machine 1 described above has numerous advantages . In the first place , the components (pocket 12 , folding spindle 16 , holding head 28 , or cutting drum 38 ) of the packing machine 1 described above made by additive manufacturing have a mass signi ficantly lower than the mass of the similar known components (with a mass reduction that can exceed 50-70% ) and therefore require less performing electric motors for the movement thereof ( therefore less bulky, cheaper and with lower energy consumption) .

Furthermore , the construction of the packing machine 1 described above is particularly simple and inexpensive since various components (pocket 12 , folding spindle 16 , holding head 28 , or cutting drum 38 ) can be manufactured quickly and inexpensively thanks to the additive manufacturing .