WO2018162514A1

WO2018162514A1 - Apparatus and method for manufacturing rods of aerosol-forming substrate

Info

Publication number: WO2018162514A1
Application number: PCT/EP2018/055527
Authority: WO
Inventors: Johannes Petrus Maria Pijnenburg; Alexandre Malgat; Noori Moyad BRIFCANI
Original assignee: Philip Morris Products S.A.
Priority date: 2017-03-08
Filing date: 2018-03-07
Publication date: 2018-09-13

Abstract

The apparatus for manufacturing a rod of aerosol-forming substrate comprises a bobbin for holding a continuous sheet (2) of aerosol-forming substrate and a rolling apparatus (6) for rolling at least a piece of the continuous sheet (2) of aerosol-forming substrate into a rod (21). The rolling apparatus (6) comprises a holder (63) for holding the at least a piece of the continuous sheet (2) of aerosol-forming substrate and a cutter for cutting a piece of aerosol-forming substrate from the continuous sheet (2) of aerosol-forming substrate. The rolling apparatus (6) also comprises a rolling mechanism (61) for rolling the at least a piece of the continuous sheet (2) of aerosol-forming substrate into a rod (21).

Description

Apparatus and method for manufacturing rods of aerosol- forming substrate

The invention relates to an apparatus and method for manufacturing a rod of aerosol-forming substrate. In particular, the invention relates to an apparatus and method for rolling aerosol-forming substrate into a rod.

In conventional cigarettes as well as in aerosol- generating articles where a tobacco substrate is combusted or heated, the substrate is made of a sheet of homogenized or reconstituted tobacco material. The sheet is crimped and then gathered transverse to a longitudinal direction of the sheet material to form a continuous rod.

It would be desirable to have a manufacturing process for tobacco rods, which is more cost efficient.

According to the invention there is provided an apparatus for manufacturing rods of aerosol-forming substrate. The apparatus comprises a bobbin for holding a continuous sheet of aerosol-forming substrate and a rolling apparatus for rolling at least a piece of the continuous sheet of aerosol- forming substrate into a rod. The rolling apparatus comprises a holder for holding the at least a piece of the continuous sheet of aerosol-forming substrate and comprises a cutter for cutting a piece of aerosol-forming substrate from the continuous sheet of aerosol-forming substrate. The rolling apparatus further comprises a rolling mechanism for rolling the at least a piece of the continuous sheet of aerosol- forming substrate, which is held by the holder, into a rod.

By rolling at least a piece of the continuous sheet of aerosol-forming substrate, that is, by rolling the continuous sheet of aerosol-forming substrate or pieces cut from the continuous sheet, the substrate does not need to be crimped for a subsequent gathering. No structuring of the aerosol- forming substrate is required to support a rod forming, in particular a controlled rod forming. The rolling process does not require special preparation of the aerosol-forming substrate for the rolling process. The rolling of the substrate allows the manufacture of reproducible rods of aerosol-forming substrate. In particular, with a given substrate and rolling parameters, a reproducible resistance to draw of rods formed subsequently or in parallel may be achieved .

A rolling mechanism may be integrated into a holder of the aerosol forming substrate.

A rolling mechanism may be a separate rolling mechanism, separate from the holder. A separate rolling mechanism may roll the at least a piece of the sheet of continuous material around the holder, while the holder is not rotated and is preferably kept stationary.

In the rolling process, preferably, the rolling mechanism is integrated into the holder. This may facilitate the set-up of the apparatus. In addition, a rolling may be localized at the position of the holder and independent of externally arranged, possibly space consuming mechanisms.

Advantageously, the holder is designed and constructed to be capable to hold the continuous sheet material before a piece is cut from the continuous sheet or the continuous sheet is cut into individual pieces. The holder is designed and constructed to hold aerosol-forming substrate, while it is being rolled into a rod. Advantageously, the holder is designed and constructed to hold a piece of aerosol-forming substrate, while the piece is being rolled.

Preferably, a holder and a cutter of a rolling apparatus are arranged and configured for holding the continuous sheet material before cutting the piece of aerosol-forming substrate from the sheet material.

A holder may, for example, hold the aerosol-forming substrate by frictional force, for example when the substrate is pressed against the holder when being rolled. The holder may, for example, hold the substrate by fixing the substrate, for example by gripping, preferably, clamping or piercing the substrate .

Preferably, a slipping of the substrate at the holder is avoided during the rolling process.

Preferably, the rolling apparatus comprises a rotatable gripper for gripping and rolling the aerosol-forming substrate. With a gripper the aerosol-forming substrate may firmly be held.

A holder may, for example, comprise a pair of pins. The pins of the pair of pins are distanced from each other such as to define a passage between the pins for arranging the at least a piece of the continuous sheet of aerosol-forming substrate to be rolled in between the pins of the pair of pins. Preferably, the continuous sheet of aerosol-forming substrate is arrangeable between the two pins before the sheet is being cut.

The holder may form a core around which the substrate is rolled. Accordingly, a holder is preferably small, for example thin or flat, such as to not cause cavities or only small cavities in the rolled rod.

Preferably, a holder is designed such as to be easily removable from the substrate when the rod has been formed. For example, a holder, in particular a gripper, may be arranged only at one or at opposite ends of the rod.

In some preferred embodiments of the apparatus, the rolling apparatus comprises a gripper comprising two oppositely arranged rotatable gripping elements, which gripping elements are rotatable in opposite directions. Each of the two gripping elements may, for example, comprise a pair of pins for gripping the substrate in between the pins. The pins of the pair of pins may be movable such that in an open position of the pins the substrate may be inserted in between the pin, and such that in a closed position of the pins the substrate is clamped between the pins.

Oppositely arranged gripping elements support a controlled rolling of the sheet material, in particular in embodiments, where the sheet material to be rolled is kept in a same axial rolling position during rolling. In particular, a controlled rolling may be performed independent on the position of the gripping elements relative to the aerosol- forming substrate. Oppositely arranged gripping elements are particularly advantageous for securely gripping the substrate to be rolled at opposite sides of an outermost end of the substrate .

Holders, in particular grippers, are preferably arranged such that aerosol-forming substrate may be rolled up from one end or may be rolled from a center of the substrate, preferably the middle of the substrate. Thus, aerosol-forming substrate may be held or gripped at an end of the substrate. The aerosol-forming substrate may also be held or gripped in the center, preferably the middle, of a piece of substrate already cut from the continuous sheet of substrate or yet to be cut from the continuous sheet of substrate.

A pair of pins or other finger-like elements for holding the substrate in between the two elements are suitable for many kind of holding the substrate, for example by frictional force only or by gripping. A rolling from an end of the substrate is preferably performed with the aid of a gripper. A gripper may securely fix the substrate in the gripper. Simple pins, where the substrate is arranged in between may allow some slipping of the substrate in between the pins. When the pins are arranged in a center of the substrate a small slipping of the substrate relative to the pins does not significantly alter or prevent a rolling of the substrate.

In the apparatus according to the invention, the continuous sheet of aerosol-forming substrate is cut by the cutter, preferably cutting a piece of aerosol-forming substrate from the continuous sheet. The continuous sheet of aerosol-forming substrate may be cut into pieces by the cutter. The cutting may be performed subsequently or may be performed in parallel, for example by the provision of more than one cutter. The cutter may also cut the continuous sheet of aerosol-forming substrate after the substrate has been rolled .

Preferably, a holder and a cutter of the rolling apparatus are arranged at a distance to each other. The distance corresponds to or is smaller than a length of the piece of aerosol-forming substrate to be cut from the continuous sheet of aerosol-forming substrate. Most preferably, the distance between cutter and holder is smaller than the length of the piece to be cut form the continuous sheet. The position of the holder and of the cutter is herein understood to represent a holding position of the holder and a cutting position of the cutter. These positions do not necessarily have to represent the exact position of the holder and cutter as apparatus parts.

In embodiments, where a piece of substrate is held at the very longitudinal edge of the substrate or of a piece to be cut, then the distance between holder and cutter corresponds substantially to the length of the piece. In embodiments, where a piece to be cut shall be held and rolled from a middle of the length of the piece, then the distance between holder and cutter corresponds to substantially half the length of a piece.

Preferably, in the apparatus according to the invention, the rolling apparatus comprises a plurality of cutters and a plurality of holders and rolling mechanisms. Preferably, the rolling apparatus comprises a same plurality of holders and rolling mechanisms and cutters.

Advantageously, the rolling apparatus comprises a plurality of cutters and a plurality of rotatable grippers, preferably a same plurality of rotatable grippers and cutters.

Neighbouring cutters and holders of the plurality of cutters and holders may be arranged at predefined distances. Preferably, the predefined distance defines the amount or length of substrate that is rolled into a rod.

Preferably, the plurality of cutters and the plurality of holders are arranged equidistantly next to each other at a distance d between neighbouring cutters and neighbouring holders. Preferably, the distance d is predefined corresponding to a diameter of a rod to be manufactured.

In embodiments with equidistantly arranged pluralities of holders and cutters, a first holder and a first cutter of the pluralities may be arranged adjacent each other. The first cutter then cuts the piece held either by the first holder or by a second holder arranged at a distance d to the first holder. The first holder may also hold a piece, which is cut by a second cutter arranged at a distance d to the first cutter. Thus, cutter and corresponding holder for holding and cutting the same piece of substrate may still be arranged at a distance corresponding substantially to the length of that piece of aerosol-forming substrate held by the corresponding holder and to be cut from the continuous sheet of aerosol- forming substrate by the corresponding cutter.

The rolling apparatus may further comprise a displacement mechanism. With the displacement mechanism, at least a piece of the continuous sheet of aerosol-forming substrate, preferably, a piece of aerosol-forming substrate cut from the continuous sheet of aerosol-forming substrate, is displaced linearly and perpendicular to a rolling direction upon being rolled. By this, a spiralling of the substrate upon rolling is performed. Preferably, the substrate is spiralled around a holder. Upon spiralling, the holder may be displaced linearly relative to the position of the substrate, or the substrate may be displaced linearly relative to the holder. Preferably, the already formed rod is axially displaced by an external moving device. The external moving device may, for example be combined by a rolling mechanism such that the moving device causes rolling as well as a translational movement of the rod .

The rolling apparatus may comprise a base for supporting the continuous sheet of aerosol-forming substrate. The continuous sheet of aerosol-forming substrate may be laid onto the base and cut on the base into individual pieces of substrate. The base may support the pieces before, during and after rolling. Preferably, the base supports the pieces before and during rolling.

The base may comprise one or a plurality of openings. Preferably, the openings have a size for a rod to fall through the opening in the base. Preferably, the openings have a rectangular shape with a width in rolling direction of less than 30 millimeter. Preferably, the sizes of the openings do not allow a piece of substrate to fall through the opening.

The apparatus according to the invention may comprise a reservoir for collecting the rods and for supplying the rods, for example, to a conveyor for further processing of the rods. The reservoir may directly be arranged after the rod forming for supplying the rods to a wrapping device for wrapping the rods .

Preferably, the apparatus according to the invention comprises a wrapping device for wrapping the rod.

Preferably, the apparatus according to the invention comprises a cutting device for cutting the wrapped rod into discrete rolled rods. Preferably, the wrapped rod is cut into single or double-length rolled rods.

The apparatus according to the invention may further comprise an adhesive application device for applying an adhesive to the wrapper, for example paper. The apparatus may also comprise a drying device for drying the adhesive.

The apparatus may comprise a control configured to control the apparatus and the elements of the apparatus, in particular a rolling apparatus. A control may control a holder and a cutter. A control preferably controls a holding, cutting and rolling action of the substrate. Preferably, a control synchronises holder and cutter.

Preferably, the control is configured to control the holder and the cutter such that the holder holds the continuous sheet of aerosol-forming substrate before the cutter cuts the piece of aerosol-forming substrate from the continuous sheet of aerosol-forming substrate.

According to the invention there is also provided a method for manufacturing a rod of aerosol-forming substrate. The method comprises the steps of providing a continuous sheet of aerosol-forming substrate and holding the continuous sheet of aerosol-forming substrate at a holding position on the continuous sheet of aerosol-forming substrate, while cutting the continuous sheet of aerosol-forming substrate. Thereby a piece of aerosol-forming substrate is produced, which is held at the holding position. The method further comprises the step of rolling the piece of aerosol-forming substrate to form a rod, while holding the piece of aerosol- forming substrate at the holding position. By this, the continuous sheet is held and the initial holding position of the continuous sheet may be kept also for the piece of substrate until the rolling process of the piece of substrate is finished.

Keeping the same holding position on the continuous sheet of substrate as well as on the cut piece of the sheet enables an efficient production, in particular also a mass production, of rolled rods of aerosol-forming substrate. Process steps are reduced and the manufacturing process is streamlined compared to, for example, a cutting of the sheet, storing cut pieces of substrate and subsequent individual rolling of the cut pieces.

The piece of substrate may be rolled in a direction parallel or perpendicular to the longitudinal axis of the continuous sheet of aerosol-forming substrate. A piece of substrate rolled in a rolling direction parallel to the longitudinal axis of the continuous sheet forms a rod having a longitudinal rod axis which rod axis is arranged perpendicular to the longitudinal axis of the continuous sheet of aerosol-forming substrate. Accordingly, a piece of substrate rolled in a rolling direction perpendicular to the longitudinal axis of the continuous sheet forms a rod having a longitudinal rod axis which rod axis is arranged parallel to the longitudinal axis of the continuous sheet of aerosol- forming substrate.

A piece of substrate and a holder may be kept in a fixed axial position (of the holder) relative to each other. A so formed rod comprises layers of substrate, wherein each layer overlies an underlying layer over an entire length of the rod .

A piece of substrate and a holder may be linearly displaced relative to each other upon rolling along a rotational axis. A so formed rod comprises a sheet of substrate that is arranged in a spiral along the rod axis.

Preferably, the method comprises rolling the piece of aerosol-forming substrate in a rolling direction parallel to the longitudinal axis of the continuous sheet of aerosol- forming substrate. Thus, preferably, a continuous sheet of aerosol-forming substrate is cut perpendicular to its longitudinal axis and the one or several individual cut pieces are rolled in the longitudinal direction, that is, in the same direction as the continuous sheet is supplied, for example from a bobbin.

Preferably, the piece of aerosol-forming substrate rolled in a rolling direction parallel to the longitudinal axis of the continuous sheet of aerosol-forming substrate is kept stationary relative to a holder. Thus, the length of the so formed rod corresponds to the width of the continuous sheet of substrate.

Preferably, the method comprises the step of gripping the continuous sheet of aerosol-forming substrate on opposite sides. Preferably, the continuous sheet is gripped at both longitudinal sides before the sheet is being cut. The positions where the sheet is gripped remains the same for the rolling of the sheet. By this, the continuous sheet may be gripped and the initial gripping position is kept until the rolling process of the piece of substrate is finished.

The method may comprise the step of holding, preferably gripping, the piece of aerosol-forming substrate at one end of the piece of aerosol-forming substrate, preferably at one longitudinal end of the substrate before rolling the piece of aerosol-forming substrate.

The method may comprises the step of holding the piece of aerosol-forming substrate in a center of the piece of aerosol-forming substrate relative to a rolling direction of the piece before rolling the piece of aerosol-forming substrate. Preferably, the piece of aerosol-forming substrate is held in the middle of the piece.

Preferably, the method comprises the step of circumscribing the rod of aerosol-forming substrate with a wrapper to form a wrapped rod. Preferably, the method also comprises the step of severing the wrapped rod into a plurality of discrete rolled rods, for example into single or double-length rods.

The continuous sheet of aerosol-forming substrate may contain tobacco material or may contain a non-tobacco material .

The continuous sheet of aerosol-forming substrate may be a continuous sheet of cellulose material impregnated with nicotine, preferably comprising one or more flavours.

Preferably the continuous sheet of aerosol-forming substrate is a continuous sheet of homogenised tobacco material, preferably comprising one or more aerosol-formers.

An aerosol-forming substrate is a substrate comprising substances, which substances may be volatilized from the substrate upon heating the substrate and which substances may form an inhalable aerosol. Advantageously, the aerosol- forming substrate comprises tobacco material.

As used herein, the term 'homogenised tobacco material' denotes a material formed by agglomerating particulate tobacco.

The rod manufactured in the apparatus or with the method according to the invention may be used in a smoking article comprising combustible smokable material and a filter downstream of the rod of combustible smokable material such as for example a cigarette.

The rod may also be used in a heated aerosol-generating article comprising a combustible heat source and a rod of aerosol-forming substrate downstream of the combustible heat source .

The rod may further be used in a heatable aerosol- generating article, wherein the aerosol-forming substrate of the rod is heated and not combusted to form an aerosol. A heat source for heating the substrate may, for example, be a chemical, electrical or combustible heat source and may be located within, around or upstream of the aerosol-forming substrate source.

Such aerosol-generating articles may be used in electrically heated aerosol-generating systems in which the aerosol-forming substrate of the heated smoking article is heated by an electrical heat source. Volatilized substances may form an aerosol for inhalation.

Preferably, the manufactured rods are of substantially uniform cross-section.

Rods may be produced having different dimensions depending upon their intended use.

For example, rods may have a diameter of between about 5 mm and about 10 mm. For example, rods may have a length of between about 5 mm and about 150 mm.

In certain embodiments, rods for use as rods of combustible smokable material in conventional lit-end smoking articles may have a length of between about 30 mm and about 140 mm.

In other embodiments, rods for use as aerosol-forming substrates in heated or heatable aerosol-forming articles may have a length of between about 5 mm and about 20 mm.

Sheets of homogenised tobacco material for use in the invention may be formed by agglomerating particulate tobacco obtained by grinding or otherwise comminuting one or both of tobacco leaf lamina and tobacco leaf stems. Alternatively, or in addition, sheets of homogenised tobacco material for use in the invention tobacco may comprise one or more of tobacco dust, tobacco fines and other particulate tobacco by-products formed during, for example, the treating, handling and shipping of tobacco.

Where rods are intended for use as aerosol-forming substrates in heated and heatable smoking articles, sheets of homogenised tobacco material preferably comprise particulate tobacco obtained by grinding or otherwise comminuting tobacco leaf lamina. In certain embodiments, sheets of homogenised tobacco material may have a tobacco content of at least about 40% by weight on a dry weight basis or of at least about 50% by weight on a dry weight basis. In other embodiments, sheets of homogenised tobacco material may have a tobacco content of about 70% or more by weight on a dry weight basis. Where rods are intended for use as aerosol-forming substrate in heated or heatable aerosol-generating articles, the use of sheets of homogenised tobacco material having high tobacco contents advantageously generates aerosols with enhanced tobacco flavour .

Sheets of homogenised tobacco material for use in the invention may comprise one or more intrinsic binders, that is tobacco endogenous binders, one or more extrinsic binders, that is tobacco exogenous binders, or a combination thereof to help agglomerate the particulate tobacco. Alternatively, or in addition, sheets of homogenised tobacco material for use in the invention may comprise other additives including, but not limited to, tobacco and non-tobacco fibres, aerosol- formers, humectants, plasticisers , flavourants, fillers, aqueous and non-aqueous solvents and combinations thereof.

Suitable extrinsic binders for inclusion in sheets of homogenised tobacco material for use in the invention are known in the art and include, but are not limited to: gums such as, for example, guar gum, xanthan gum, arabic gum and locust bean gum; cellulosic binders such as, for example, hydroxypropyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose and ethyl cellulose; polysaccharides such as, for example, starches, organic acids, such as alginic acid, conjugate base salts of organic acids, such as sodium-alginate, agar and pectins; and combinations thereof.

Suitable non-tobacco fibres for inclusion in sheets of homogenised tobacco material for use in the invention are known in the art and include, but are not limited to: cellulose fibers; soft-wood fibres; hard-wood fibres; jute fibres and combinations thereof. Prior to inclusion in sheets of homogenised tobacco material for use in the invention, non-tobacco fibres may be treated by suitable processes known in the art including, but not limited to: mechanical pulping; refining; chemical pulping; bleaching; sulfate pulping; and combinations thereof. Sheets of aerosol-forming substrate, in particular, sheets of homogenised tobacco material for use in the invention should have sufficiently high tensile strength to survive being rolled to form rods. In certain embodiments non-tobacco fibres may be included in sheets of homogenised tobacco material in order to achieve an appropriate tensile strength .

For example, homogenised sheets of tobacco material for use in the invention may comprise between about 1 % and about 5% non-tobacco fibres by weight on a dry weight basis.

Suitable aerosol-formers and humectants for inclusion in sheets of homogenised tobacco material for use in the invention are known in the art and include, but are not limited to: polyhydric alcohols, such as triethylene glycol, 1 , 3-butanediol and glycerine; esters of polyhydric alcohols, such as glycerol mono-, di- or triacetate; and aliphatic esters of mono-, di- or polycarboxylic acids, such as dimethyl dodecanedioate and dimethyl tetradecanedioate.

In certain preferred embodiments, sheets of homogenised tobacco material comprising one or more aerosol-formers have an aerosol former content of greater than 5% on a dry weight basis. In other preferred embodiments, an aerosol former content is between about 5% and about 30% by weight on a dry weight basis.

A number of reconstitution processes for producing sheets of homogenised tobacco materials are known in the art.

Sheets of homogenised tobacco material for use in the invention are preferably formed by a casting process of the type generally comprising casting a slurry comprising particulate tobacco and one or more binders, possibly comprising one or more aerosol formers onto a conveyor belt or other support surface, drying the cast slurry to form a sheet of homogenised tobacco material and removing the sheet of homogenised tobacco material from the support surface.

For example, in certain embodiments sheets of homogenised tobacco material for use in the invention may be formed from a slurry comprising particulate tobacco, guar gum, cellulose fibres and glycerine by a casting process.

Rods may be produced from sheets of aerosol-forming substrate, in particular of homogenised tobacco material having different dimensions depending upon their intended use.

Preferably, sheets of aerosol-forming substrate, in particular of homogenised tobacco material for use in the invention have a width of at least about 25 mm. In certain embodiments sheets of aerosol-forming substrate, in particular of homogenised tobacco material for use in the invention may have a width of between about 25 mm and about 300 mm, more preferably between 200 mm and 300 mm.

Preferably, sheets of aerosol-forming substrate, in particular of homogenised tobacco material for use in the invention have a thickness of at least about 50 micrometer.

In certain embodiments, sheets of aerosol-forming substrate, in particular of homogenised tobacco material for use in the invention may have a thickness between 0.1 millimeter and 2 millimeter, preferably between 0.3 millimeter and 1.5 millimeter, for example, 0.8 millimeter .

The invention is further described with regard to embodiments, which are illustrated by means of the following drawings, wherein:

Fig. 1 shows an overview over a manufacturing process of an aerosol-forming rod;

Fig. 2 to 7 show a holding and rolling process of a sheet material ;

Fig. 8 to 13 show an apparatus and manufacturing process of a plurality of aerosol-forming rods;

Fig. 14 illustrates a spiralling rolling process in a perspective view;

Fig. 15 illustrates a spiralling rolling process comprising two sheets;

Fig. 16 shows an embodiment for manufacturing rods comprising a spiral rolled sheet of aerosol- forming substrate.

Fig. 1 shows a schematic overview of a manufacturing process of rolled rods. A continuous sheet 2 of homogenized tobacco material is mounted on a bobbin 4. The sheet 2 is fed, through a series of rollers and tensioners 3, to a rolling apparatus 6. The rolling apparatus 6 forms rods out of the sheet 2. The rolling apparatus 6 will be described in more detail with reference to the following figures.

Rods 21 formed in the rolling apparatus 6 are transported through a converging funnel 7 onto a conveyor belt 9. After exiting the funnel 7 the rolled rods are wrapped into wrapping material 12, typically paper. The wrapping material 12 is fed from a bobbin 14 from below the conveyor belt 9. An adhesive application device 16 is arranged downstream of the wrapper supply location. With the adhesive application device 16 an adhesive is applied to one of the longitudinal edges of the continuous sheet of wrapping material 12. Thus, when opposed longitudinal edges of wrapping material wrapped around the rods are brought into contact they adhere to one another. The adhesive is then dried by drying means 18, for example a fan or infrared lamp. Lastly, a rotary cutter 20 may sever the wrapping material or may sever the wrapped rods into rod units each one having the desired length or multiple unit length. For example single length rods or double length rods may be formed, for example having a length of between 5 mm and 20 mm.

In the sequence shown in Figs. 2 to 4, a mode of holding the tobacco sheet 2 is shown. This way of holding may be used for example in the rolling apparatus of Fig. 1.

A couple of opposed pair of fingers 63, for example metal grippers, can assume an open configuration, having fingers distances from each other, and a gripping configuration where fingers abut each other. Each couple of fingers 63 is connected to a respective servomotor 61 through a telescopic arm 62. Furthermore, the pair of fingers 63 is rotatable about an axis aligned with the telescopic arm 62.

In Fig. 2 the homogenized tobacco sheet 2 is shown in a front view and it advances, during process, along a direction perpendicular to the plane of the drawing, for example as the bobbin 4 is unwound.

When a front edge of the tobacco sheet 2 reaches a position substantially correspondent to the position of the fingers 63, the advancement of the tobacco sheet 2 is stopped .

Telescopic arm 62 moves the two couple of fingers 63 in the open configuration versus each other such that the pair of fingers surrounds the tobacco sheet 2.

As shown in Fig. 3, the fingers 63 are then brought into the closed configuration, such as to fix the edges of the tobacco sheet 2 between the fingers. The gripping pressure of the fingers 63 and the tension applied to the sheet 2 via the arm 62 is preferably calibrated such to ensure that the fingers do not damage the sheet. In addition, the sheet 2 is not too stretched nor too loose in order not to damage nor lose the sheet. For this reason, fingers 63 are preferably provided in the form of opposing pins.

With reference now to the sequence of Fig. 5 to 7 a rod is formed. In Fig. 5, each pair of fingers 63 rotates about its axis in the direction of the arrow and roll the tobacco sheet 2 around the fingers as may be seen in Fig. 6.

Subsequently, as shown in Fig. 7, the fingers 63 are brought back into the open configuration, which may be a minimal opening of the two fingers, such as to release the formed rod 21. The fingers 63 are then retracted through retraction of the telescopic arms 62.

A rolling apparatus 6 is shown in Fig. 8 in a top view. In this preferred but non-limiting embodiment, the process is a step-wise process and the bobbin 4 is stopped at regular time intervals while the rolling operations are carried out. A plurality of couples of opposed pairs of fingers 63 are located in series along the unwound tobacco sheet 2. The distance d between two subsequent couples of opposed fingers 63 is arranged such as to achieve a desired thickness of the rod after the sheet has been rolled.

In the embodiment shown in Fig. 8 the rolling apparatus 6 comprises five couples of opposed fingers 63. It will be appreciated that the number of fingers may be more than five or less than five, according to manufacturing necessities.

The bobbin 4 of homogenized tobacco sheet is unwound on a working surface 5 comprising elongated rectangular through- holes 51. Each through-hole 51 is arranged substantially in^¬ line with a respective opposed couple of finger pair 63. As shown in Fig. 9, the homogenized tobacco sheet 2 is unwound from the bobbin 4 onto the working plate 5. The finger are in the retracted position. As shown in Fig. 10, the fingers have reached, through telescopic arm 62 driven by servomotor 61, a positon such that they surround respective edges of tobacco sheet 2. The fingers 63 then assume the gripping configuration such as to fix the respective opposed edges of tobacco sheet 2.

A cutting apparatus (not shown) , preferably comprising a plurality of cutters, carries out a number of, preferably simultaneous, cuts along dashed lines 65. Individual pieces of tobacco sheet are created, which pieces define the amount of tobacco on a rod. The cuts are performed next to a finger 63 such that the fingers hold the piece of sheet material close to opposed corners of the piece at an end of the piece. Thus, except for the most upstream cutter and the most downstream holder, holders and cutters are arranged adjacent each other.

However, as may be seen in the figure, a holder and a corresponding cutter, for example for the rightmost piece of substrate, are distanced from each other by a little less than the length of the piece cut from the continuous substrate. Due to the holding positions of the holders on the continuous sheet each at substantially the downstream (virtual) edges of the pieces to be cut, each distance between a holder and its corresponding cutter corresponds to substantially the length of the pieces.

In Fig. 11 the start of the parallel rolling process is shown. In Fig. 12, the fingers have been rotated giving the tobacco sheet 2 a circumferential shape and forming rods 21. The subsequent release of the fingers from the thus-formed rods 21 by retraction of the telescopic arms cause the rods to fall through the elongated through-holes 51. The rods 21 are collected in the below converging funnel 7, as shown in Fig. 13. With reference to Fig. 1, the converging funnel 7 is advantageously arranged such to dispose formed rods 21 into an aligned sequence on the conveyor 9 to make it possible to apply the wrapping material 12 as above described.

Depending on the sheet material forming the rods, the rods may directly be wrapped to prevent an unrolling of the sheet. In such an embodiment a wrapper for wrapping the rods is preferably directly arranged subsequent to the rolling apparatus and before any collection means such as a converging funnel. In such an embodiment, the rods may, for example be transported on the working surface to a wrapping device. Through-holes in the working surface 5 may then be omitted .

Also a gripping and cutting of the sheet material as shown in Fig. 10 may vary. For example, the cutting of the continuous sheet material 4 may be performed such that the fingers 63 hold the sheet at the opposed longitudinal edges of the continuous sheet but not at an end portion of the cut piece but, for example in the middle of the piece. The piece may then be rolled around the fingers from both sides.

Fig. 14 shows a holder in the form of a rotatable pin 64. While the pin 64 rotates, the sheet of aerosol-forming substrate 2 is spiraled around the pin 64.

In this embodiment the pin 64 may move linearly in the longitudinal direction of the pin 64 corresponding to a transport direction 300 of the rod 21 being formed. Alternatively, the pin may be stationary relative to its axial position and the rod may be moved in axial direction by slipping along the pin by support of an external moving device (not shown) .

A supply direction 100 of the sheet 2, a rotation direction 200 of the rod 21 while being formed and the transport direction 300 of the rod 21 while being formed is indicated with arrows.

The individual windings of the sheet of substrate 2 are displaced by about 0.5 mm to about 4 mm, for example by about 1 mm to 2 mm. A displacement distance may be selected dependent on the thickness of the sheet material, the space required by the pin, and the diameter of the rod to be formed .

Fig. 15 shows a similar manufacturing method as shown in Fig. 14, however, with two sheets 2,22 supplied simultaneously to the pin 64.

Dimensions of the rod 21 formed and of a displacement of the windings of the rods 21 may be kept the same as for one sheet. The sheets are in alternate manner wound around pin 64.

The sheets 2,22 may be the same type of sheets, for example, two sheets or aerosol-forming substrate, in particular the same type of tobacco sheets. The sheets 2,22 may be different types of aerosol-forming substrate sheets. If different types of sheets of aerosol-forming substrate are used, the sheets preferably differ in an amount of nicotine, in the kind of tobacco or in flavor or in a combination of the afore-mentioned. The sheets 2,20 may also be different sheets. For example, one sheet 2 is an aerosol-forming substrate and the other sheet 20 is a sheet of inductively heatable material such as for example a susceptor band, preferably an aluminium or stainless steel foil.

The inductively heatable material, preferably a susceptor material is rolled into the rod together with the sheet of aerosol-forming substrate.

By rolling the susceptor material with the sheet of aerosol-forming substrate 2 an inductively heatable aerosol- forming substrate is formed.

The merging of the two sheets, in particular the merging of a susceptor material and an aerosol-forming substrate provides a close contact of the two solids. An inductively heatable rod formed from or comprising such an inductively heatable aerosol-forming substrate may have a good heat distribution and a homogeneous temperature distribution over a cross-section or length of the rod.

Preferably, the sheet of susceptor material is a ferromagnetic tape.

If different sheets are used a manufacturing process for the different sheets may be optimized according to different characteristics of the sheets.

In Fig. 16 an example of a manufacturing process for spiraled rods comprising a moving device is illustrated. Four guide rollers 65 are arranged at the circumference of the rod 21. The four rollers 65 have a rotational axis parallel to the longitudinal axis of the rod 21. The four rollers 65 rotate in a counter direction than the rod 21. In Fig. 16 the rod 21 rotates anti-clockwise and the rollers 65 rotate clockwise .

The guide rollers touch the rod 21 at its circumference and support the rod forming or make the sheet to be rolled.

The guide rollers press the sheet against the underlying winding of the sheet thereby supporting the forming of a dense rod and preventing the forming of bumps or ripples in the sheet. If the rollers are driven rollers they may cause the rod to rotate. A holder, possibly a rotatable holder where the sheet is rolled around may then be omitted.

The guide rollers 65 are preferably also used as transport rollers, transporting the rod 21 into the longitudinal direction of the guide rollers. By using guide rollers, a pin 64 as shown in Fig. 14 and Fig. 15 does not necessarily have to extend along the length of the rod and does not need to be linearly displaced but may remain in a fixed axial position. Newly supplied sheet is then supported by the pin 64, while the rolled rod 21 is transported by the guide rollers 65.

A linear displacement of the rod 21 and by this a narrow or wide spiralling of the sheet may be defined by the axial movement of the rollers 65.

Claims

Apparatus for manufacturing a rod of aerosol-forming substrate, the apparatus comprising

a bobbin for holding a continuous sheet of aerosol- forming substrate;

a rolling apparatus for rolling at least a piece of the continuous sheet of aerosol-forming substrate into a rod;

wherein the rolling apparatus comprises a holder for holding the at least a piece of the continuous sheet of aerosol-forming substrate and a cutter for cutting a piece of aerosol-forming substrate from the continuous sheet of aerosol-forming substrate, and further

comprises a rolling mechanism for rolling the at least a piece of the continuous sheet of aerosol-forming substrate into a rod.

Apparatus according to claim 1, wherein the rolling mechanism is integrated into the holder.

Apparatus according claim 2, comprising a rotatable gripper .

Apparatus according to any one of the preceding claims, wherein the holder comprises a pair of pins, and wherein the pins of the pair of pins are distanced from each other such as to define a passage between the pins for arranging the at least a piece of the continuous sheet of aerosol-forming substrate in between the pins of the pair of pins.

5. Apparatus according to any one of claims 2 to 4, comprising two oppositely arranged rotatable gripping elements, which gripping elements are rotatable in opposite directions.

6. Apparatus according to any one of claims 1 to 4,

wherein the rolling apparatus comprises a displacement mechanism such that at least a piece of the continuous sheet of aerosol-forming substrate is displaced

linearly and perpendicular to a rolling direction upon being rolled.

7. Apparatus according to any one of the preceding claims, comprising a wrapping device for wrapping the rod.

8. Apparatus according to any one of the preceding claims, wherein the rolling apparatus comprises a plurality of cutters and a plurality of holders and rolling

mechanisms .

9. Apparatus according to claim 8, wherein the plurality of cutters and the plurality of holders are arranged equidistantly next to each other at a distance d between neighbouring cutters and neighbouring holders.

10. Method for manufacturing a rod of aerosol-forming

substrate, the method comprising the steps of:

providing a continuous sheet of aerosol-forming

substrate;

holding the continuous sheet of aerosol-forming

substrate at a holding position on the continuous sheet of aerosol-forming substrate, while cutting the continuous sheet of aerosol-forming

substrate, thereby producing a piece of aerosol-forming substrate which is held at the holding position; and rolling the piece of aerosol-forming substrate to form a rod, while holding the piece of aerosol-forming substrate at the holding position.

11. Method according to claim 10, therein rolling the piece of aerosol-forming substrate in a rolling direction parallel to the longitudinal axis of the continuous sheet of aerosol-forming substrate.

12. Method according to any one of claims 10 to 11,

comprising the step of gripping the continuous sheet of aerosol-forming substrate on opposite sides of the sheet . 13. Method according to any one of claims 10 to 12,

comprising the step of holding the piece of aerosol- forming substrate at one end of the piece of aerosol- forming substrate or in a center of the piece of aerosol-forming substrate relative to a rolling

direction of the piece, before rolling the piece of aerosol-forming substrate.

14. Method according to any one of claims 10 to 13, further comprising the steps of circumscribing the rod of aerosol-forming substrate with a wrapper to form a wrapped rod; and

severing the wrapped rod into a plurality of discrete rolled rods. Method according to any one of claims 10 to 14, wherein the continuous sheet of aerosol-forming substrate is a continuous sheet of homogenised tobacco material comprising one or more aerosol-formers.