Rod element with helical wrapper

Abstract

The invention relates to an apparatus for manufacturing a rod element with a helical wrapper. The apparatus comprises a hollow winding guide (10), a filling unit configured for continuously filling a porous filling material into an upstream end of the hollow winding guide, a band provision unit configured for guiding at least one band of wrapping material (100) towards the hollow winding guide, and a winding unit configured for winding the at least one band of wrapping material around the hollow winding guide to provide an endless helically wrapped rod. The invention further relates to a method for manufacturing a rod element with a helical wrapper. The invention further relates to a consumer article.

Description

[0001] ROD ELEMENT WITH HELICAL WRAPPER

[0002] The present disclosure relates to an apparatus for manufacturing a rod element with a helical wrapper. The present disclosure further relates to a method for manufacturing a rod element with a helical wrapper. The present disclosure further relates to a consumer article.

[0003] It is known to provide consumer articles, for example aerosol-generating articles, comprising one or more rod elements arranged in series along a longitudinal axis of the article. Known rod elements of aerosol-generating articles include, for example, a mouthpiece filter, an aerosol-forming substrate portion, a hollow tubular element, and a front plug. Those rod elements, for example the mouthpiece filter or the front plug, may be configured as cylindrical plugs made of a porous material, for example a porous filter material. It is known to provide outer wrappers to surround one or more of the rod elements or the entire article.

[0004] Those wrappers are typically provided by a sheet of paper or other material, the sheet circumscribing the entire circumference of the rod element or article. The width of the wrapper sheet typically slightly exceeds the circumference of the rod element such that overlapping end portions of the wrapper sheet linearly extend along the longitudinal axis of the rod element or article. The overlapping end portions are typically adhered to one another by a line of glue applied between the overlapping end portions along the longitudinal axis.

[0005] Application of glue typically requires a step of pressing onto the overlapping region of the wrapped rod and heating the wrapping material to dry the glue and seal the wrapper. This is often accomplished by a heating bar that simultaneously presses and heats. It may, however, be difficult to always apply the correct pressure by the heating bar. Using too little pressure may result in improper closure of the wrapper. Applying too much pressure might result in deformation of the rod. These problems may be particularly severe when new porous materials are to be applied which might not always exhibit a compression resistance that is compatible with the heating bar apparatus. The question of compression resistance maybe particularly important when porous materials are to be wrapped.

[0006] It would be desirable to provide an apparatus and method for wrapping rod elements that is compatible with novel materials of various compression resistances. It would be desirable to provide a method and apparatus that allows to wrap rod elements with reduced risk of deformation of the rod elements. It would be desirable to provide a method and apparatus that allows to wrap rod elements with reduced risk of incomplete closure of the wrapper.

[0007] According to an embodiment of the invention there is provided an apparatus for manufacturing a rod element with a helical wrapper. The apparatus may comprise a hollow winding guide. The apparatus may comprise a filling unit. The filling unit may be configured for filling, preferably for continuously filling, a filling material into the hollow winding guide, preferably into an end of the hollow winding guide, more preferably into an upstream end of the hollow winding guide. The filling material may be a porous filling material. The apparatus may comprise a band provision unit. The band provision unit may be configured for guiding at least one band of wrapping material towards the hollow winding guide. The apparatus may comprise a winding unit configured for winding the at least one band of wrapping material around the hollow winding guide. The apparatus may comprise a winding unit configured for winding the at least one band of wrapping material around the hollow winding guide to provide a helically wrapped rod, preferably an endless helically wrapped rod.

[0008] According to an embodiment of the invention there is provided an apparatus for manufacturing a rod element with a helical wrapper. The apparatus comprises a hollow winding guide. The apparatus comprises a filling unit. The filling unit is configured for continuously filling a porous filling material into an upstream end of the hollow winding guide. The apparatus comprises a band provision unit. The band provision unit is configured for guiding at least one band of wrapping material towards the hollow winding guide. The apparatus comprises a winding unit. The winding unit is configured for winding the at least one band of wrapping material around the hollow winding guide to provide an endless helically wrapped rod.

[0009] An apparatus that may be compatible with novel materials is provided. An apparatus that may be compatible with materials of various compression resistances is provided. An apparatus is provided that may allow to wrap rod elements with reduced risk of deformation of the rod elements. And apparatus is provided that may allow to wrap rod elements with reduced risk of incomplete closure of the wrapper.

[0010] By the apparatus of the invention, the helical wrapper may strongly hold the filling material inside the rod, even if the filling material has a significant expansion strength. If needed, additional layers of wrapping material may be easily added using the same overall winding system to reinforce the walls. The hollow winding guide may allow to assure a correct ovality of the rod. Due to the hollow winding guide, there is no or little risk of the correct ovality being jeopardized during forming of the endless helically wrapped rod. For example, no heating bar which may deform the rod presses onto the rod on forming the rod.

[0011] As the helical wrapper is formed by winding the at least one band of wrapping material around the hollow winding guide and the filling material is filled into the hollow winding guide, the walls of the winding guide physically separate the helical wrapper from the filling material during filling. The helical wrapper first contacts the filling material downstream of the winding guide when the helical wrapper is already formed. Thereby frictional forces between the filling material and the helical wrapper during filling and during forming of the helical wrapper may be reduced or avoided. Transversal expansion forces of the filling material against the helical wrapper during filling and during forming of the helical wrapper may be reduced or avoided. Risk of damaging and deformation of the helically wrapped rod element may be reduced. Reduced frictional forces may enable to avoid increased temperature in the parts and equipment components in contact. Premature wear and dimensional deformation by friction may be avoided or reduced. This may be particularly advantageous in conjunction with paperbased materials which are abrasive, namely at the linear speeds of the referred manufacturing process.

[0012] At a downstream end of the hollow winding guide, transversal expansion forces of the filling material may be exerted on the inner wall of the pre-formed, and optionally glued, helical wrapper, which is then solid enough to sustain such pressure. The transversal expansion force of the filling material may create a strong attachment of the filling material with the walls of the helical wrapper. Parameters of the filling material like density and / or type of material may be varied. The apparatus of the invention may allow to easily vary the filling material and / or its packing density.

[0013] For example, adjusting the quantity of a filling material inserted into the hollow winding guide per time may change the density of the resulting rod elements. For example, filter elements with different RTD (Resistance-To-Draw) values as well as a different filtration properties may be easily obtained. The apparatus of the invention may thereby allow to impact directly on key features of the rod elements, by means of acting on the somehow “easy to adjust” parameters of insertion, for example by varying the relative speed of a piston or rollers for insertion of the filling material into the hollow winding guide reported to the overall manufacturing speed of the rod element.

[0014] The rod element may be a rod element for a consumer article. The rod element may be part of a consumer article or may be a consumer article. The consumer article may comprise a mouth end. The consumer article may be an aerosol-generating article.

[0015] The filling material may be a porous material. The filling unit may be configured for continuously filling a porous material into the upstream end of the hollow winding guide.

[0016] The filling unit may comprise an inside arm.

[0017] The inside arm may extend into an upstream portion of the hollow winding guide. The inside arm may be configured to conduct a to-and-fro motion with respect to a longitudinal axis of the hollow winding guide. The longitudinal axis of the hollow winding guide may extend between the upstream end and a downstream end of the hollow winding guide.

[0018] The to-and-fro motion of the inside arm may allow to push the filling material into the winding guide. The to-and-fro motion of the inside arm may allow to both push the filling material into the hollow winding guide and compress the filling material.

[0019] The inside arm may be connected to a piston to allow the to-and-fro motion of the inside arm.

[0020] The inside arm may be configured as a cylindrical element. The inside arm may be configured as right circular cylinder. The inside arm may be arranged concentrically with the hollow winding guide. A diameter of the inside arm may be less than an inner diameter of the hollow winding guide. A diameter of the inside arm may be 20 percent or less, 15 percent or less, or 10 percent or less of an inner diameter of the hollow winding guide. The inner diameter of the hollow winding guide may be between 4 millimeters and 10 millimeters, preferably between 4.5 millimeters and 9 millimeters, more preferably between 5 millimeters and 8 millimeters.

[0021] The inside arm may be configured to rotate around its longitudinal axis. This may add an internal winding to the filling material.

[0022] The inside arm may have a textured asymmetrical surface. This may help to push the filling material into the hollow winding guide.

[0023] The inside arm may comprise at least one protruding feature on the cylindrical surface.

[0024] The protruding feature may be configured as a cone-shaped protrusion around a cylindrical axis of the inside arm. A base of the cone-shaped protrusion may face towards the downstream end of the hollow winding guide when the inside arm is inserted into the hollow winding guide. Thereby, the base may help to push the filing material into the hollow winding guide along the downstream direction when the inside arm moves in the downstream direction. When the inside arm moves back in the upstream direction, a smoother cone surface may help retracting of the inside arm without pulling back the filling material.

[0025] The at least one protruding feature may be configured as at least one barb.

[0026] The at least one protruding feature may be configured as at least one movable rib. The at least one movable rib may be movable between a first position and a second position. In the first position, the movable rib may be arranged transversal to a longitudinal axis of the inside arm. The movable rib may be configured to be in the first position when the inside arm moves in a direction towards the hollow winding guide. The movable rib may be configured to be in the first position when the inside arm moves in a downstream direction. In the second position, the movable rib may be arranged in alignment with the longitudinal axis of the inside arm. The movable rib may be configured to be in the second position when the inside arm moves in a direction away from the hollow winding guide. The movable rib may be configured to be in the second position when the inside arm moves in an upstream direction.

[0027] By the protruding feature, frictional forces of the inside arm with respect to the filling material may be made higher when the inside arm moves into the downstream direction into the hollow winding guide as compared to when the inside arm is retracted into the upstream direction out of the hollow winding guide. This may help pushing the filling material along the downstream direction.

[0028] The inside arm may have a pointed end. The filling unit may comprise a rotating screw conveyer extending into at least an upstream portion of the hollow winding guide. The rotating screw conveyer may be an Archimedes’ screw. The rotating screw conveyer may be a screw feeder.

[0029] The rotating screw conveyer may be configured to rotate in the same direction as the helical wrapper surrounding the hollow winding guide. The rotating screw conveyer may be configured to rotate with the same speed as the helical wrapper surrounding the hollow winding guide.

[0030] The rotation of the rotating screw conveyer may impair a rotational, helical movement to the filling material. The helical movement of the filling material may be synchronized with the helical movement of the helical wrapper surrounding the hollow winding guide. Thereby, frictional forces between the helical wrapper and the filling material when they contact after the downstream end of the hollow winding guide may be reduced.

[0031] The filling unit may comprise one or more roller pairs configured for transporting a band of the filling material into the hollow winding guide. The filling unit may comprise a first roller pair configured for pushing the band of filling material into a converging tool. The filling material may be guided between the first roller pair. The filling unit may comprise a second roller pair downstream of the converging tool configured for pulling the band of filling material out of the converging tool and further into the hollow winding guide. The filling material may be guided between the second roller pair. The converging tool may be a converging funnel.

[0032] One or both of sandwiching the filling material between the one or more roller pairs, and guiding the filling material into the converging tool, may be particularly advantageous for pretreating filling materials with a strong resistance to compression.

[0033] The hollow winding guide may be tubular. The hollow winding guide may comprise a tubular main body. The hollow winding guide may be tube-shaped. The hollow winding guide may have a tube-shaped main body.

[0034] As used herein, the terms ‘tubular’, ‘tube-shaped’, and ‘tubular shape’ refer to three- dimensional objects and three-dimensional geometric shapes comprising a bottom basal plane, a top basal plane, and a sidewall circumscribing a hollow interior, the sidewall being arranged between the bottom basal plane and the top basal plane. The sidewall extends along a longitudinal axis of the tubular element between the bottom basal plane and the top basal plane. The longitudinal axis may be perpendicular to one or both of the bottom basal plane and the top basal plane.

[0035] A bottom base of the tubular object lies within the bottom basal plane. A top base of the tubular object lies within the top basal plane. A cross-sectional shape of one or both of the bottom and top bases may be circular. A cross-sectional shape of one or both of the bottom and top bases may be non-circular, for example elliptic, stadium-shaped, or rectangular. One or both of the bottom base and the top base may be at least partly open to provide an internal hollow passage of the tubular object.

[0036] The tubular object may have the shape of a circular hollow cylinder. The tubular object may have the shape of a right circular hollow cylinder. The tubular object may have the shape of a non-circular hollow cylinder, for example an elliptic hollow cylinder, or a stadium-shaped hollow cylinder.

[0037] The longitudinal axis of the tubular object may be arranged in parallel to the downstream direction.

[0038] An outer diameter of the hollow winding guide may be between 3 millimeters and 3 centimeters, preferably between 4 millimeters and 10 millimeters, more preferably between 6 millimeters and 8 millimeters, more preferably between 6.5 millimeters and 7.5 millimeters.

[0039] A thickness of a sidewall of the tube-shaped hollow winding guide may be between 0.5 millimeter and 1.5 millimeters.

[0040] A length of the tube-shaped hollow winding guide may be between 1 meter and 3 meters.

[0041] The tube-shaped hollow winding guide may be configured as a stainless steel tube.

[0042] The hollow winding guide may comprise a funnel-shaped opening. The hollow winding guide may comprise a funnel-shaped opening of the upstream end of the hollow winding guide. The funnel shape may help compressing the filling material.

[0043] The hollow winding guide may comprise a glue channel.

[0044] The glue channel may allow to inject glue between the filling material and an inner side of the helical wrapper to glue them together at the downstream end of the winding guide. This may be particularly advantageous when exerting an external pulling action on helical wrapper to pull the endless helically wrapped rod in a downstream direction.

[0045] The glue may be a cold glue. The glue may be a water-soluble polymer having strong adhesive property which solidifies when the water goes away due to heat.

[0046] The helicoidal movement of the helical wrapper may additionally spread the glue over the inner surface of helical wrapper, providing a large surface of gluing for the filling material to the helical wrapper.

[0047] The glue channel may comprise an inlet opening configured for receiving glue and an outlet opening. The inlet opening may be arranged at an upstream end of the hollow winding guide.

[0048] The outlet opening of the glue channel may be arranged within the hollow winding guide. The outlet opening of the glue channel may be arranged at a downstream end of the hollow winding guide. The glue channel may extend past a main body of the hollow winding guide such that the outlet opening of the glue channel is arranged downstream of the end of the main body. The apparatus may comprise a heating station. The heating station may be configured for heating the endless helically wrapped rod. The heating station may be arranged downstream of the hollow winding guide. The heating station may accelerate drying of the glue exiting the glue channel. The heating station may additionally assist in drying glue applied on the band or bands of wrapping material of the helical wrapper.

[0049] The apparatus may comprise a glue pump. The glue pump may be configured for injecting glue into the inlet opening of the glue channel.

[0050] The hollow winding guide may have a low friction surface. The low friction surface may be provided by a low friction coating. The hollow winding guide may comprise a low friction coating. The low friction coating may be an amorphous nano-composite coating. Amorphous nano-composite coatings may provide a combination of high hardness and low friction properties. The low friction coating may be selected from Diamond-Like Carbon (DLC) and Titanium-Doped Molybdenum Disulfide (TiMoS2). The low friction coating may be a metallic alloy, for example a ferromagnetic alloy. The metallic alloy may be applied by Radio Frequency, Magnetron Sputtering Physical Vapor Deposition (RF-MSPVD), or Plasma Assisted Chemical Vapor Deposition (PACVD).

[0051] The hollow winding guide may have a diamond-like carbon coating.

[0052] The winding unit may be configured for winding the at least one band of wrapping material around the hollow winding guide such that the band does not overlap itself.

[0053] The winding unit may be configured for winding the at least one band of wrapping material around the hollow winding guide such that a pitch of a full helical turn of a band of wrapping material around the winding guide is equal to a width of said band of wrapping material.

[0054] The winding unit may be configured for winding a plurality of bands of wrapping material around the hollow winding guide, preferably two bands, three bands, or four bands.

[0055] Using a plurality of bands of wrapping material to form the helical wrapper may allow using a small thickness of the multi-layered wrapper while still providing sufficient mechanical stability.

[0056] The winding unit may be configured for winding the plurality of bands of wrapping material around the hollow winding guide such that neighboring bands overlap each other. Preferably, each band overlaps at most one neighboring band. Preferably, each band is overlapped by at most one neighboring band.

[0057] As used herein, “a band of wrapping material overlapping a neighboring band of wrapping material” refers to a direct overlap of two directly neighboring bands including a physical contact of the two bands.

[0058] The plurality of bands of wrapping material may comprise an inner band and one or more outer bands. The winding unit may be configured for winding the one or more outer bands around the inner band. The apparatus may comprise a gluing unit configured to apply glue onto the one or more outer bands and not to apply glue onto the inner band.

[0059] The apparatus may comprise an advancing mechanism configured for advancing the endless helically wrapped rod along a downstream direction. The apparatus may comprise an advancing mechanism configured for helically advancing the endless helically wrapped rod along a downstream direction. The advancing mechanism may be configured for pulling the endless helically wrapped rod away from the winding guide. The advancing mechanism may be configured for pulling and the endless helically wrapped rod away from the winding guide and rotating the endless helically wrapped rod. The advancing mechanism may comprise an endless belt. The advancing mechanism may form part of the winding unit.

[0060] The winding unit may comprise an endless belt. The endless belt of the winding unit may be configured for continuously rotating and pulling the endless helically wrapped rod along a downstream direction. The endless belt of the winding unit may be driven by two rotating cylinders. The two rotating cylinders may be arranged vertically to a longitudinal axis of the hollow winding guide. The endless belt of the winding unit may be helically arranged around the endless helically wrapped rod.

[0061] The apparatus may comprise a cutting unit arranged downstream of the hollow winding guide. The cutting unit may be configured to cut the endless helically wrapped rod into helically wrapped rod elements.

[0062] The cutting unit may be configured to transversally cut the entire cross-section of the endless helically wrapped rod.

[0063] The cutting unit may comprise a rotating knife.

[0064] The cutting unit may comprise an array of circular knifes.

[0065] The cutting unit may comprise a moving support configured for holding the cut helically wrapped rod elements.

[0066] The hollow winding guide may be fixed. The hollow winding guide may be configured immobile within the apparatus.

[0067] The apparatus may comprise a motor configured for rotating the hollow winding guide around its longitudinal axis.

[0068] The apparatus may comprise a gluing unit. The gluing unit may be configured to apply glue to at least one band of wrapping material before being wound around the hollow winding guide.

[0069] The gluing unit may comprise one or both of a glue roller and a glue nozzle configured for applying the glue. The glue may be used as a liquid glue and applied via a glue roller on the inner sides of the respective the band or bands of wrapping material.

[0070] The gluing unit may be configured to apply one or both of ethylene-vinyl acetate-based glue and poly-vinyl acetate glue. The glue applied to the band or bands of wrapping material may comprise a quick action glue, for example ethylene-vinyl acetate-based glue. Long lasting glue, for example poly-vinyl acetate glue, may be used in combination with a quick action glue. The gluing unit may comprise a dryer station.

[0071] Different filling materials may be used. The filling unit may be configured for continuously filling a plurality of different filling materials into the upstream end of the hollow winding guide.

[0072] According to an embodiment of the invention there is provided a method for manufacturing a rod element with a helical wrapper. The method may comprise providing a hollow winding guide. The method may comprise helically winding at least one band of wrapping material around the hollow winding guide to form a helically wrapped rod, preferably an endless helically wrapped rod. The method may comprise filling a filling material into the hollow winding guide. The filling material may be a porous filling material. The method may comprise filling a filling material into the hollow winding guide such that the endless helically wrapped rod is filled with the filling material.

[0073] According to an embodiment of the invention there is provided a method for manufacturing a rod element with a helical wrapper. The method comprises providing a hollow winding guide. The method comprises helically winding at least one band of wrapping material around the hollow winding guide to form an endless helically wrapped rod. The method comprises filling a porous filling material into the hollow winding guide such that the endless helically wrapped rod is filled with the filling material.

[0074] A method that may be compatible with novel materials is provided. A method that may be compatible with materials of various compression resistances is provided. A method is provided that may allow to wrap rod elements with reduced risk of deformation of the rod elements. A method is provided that may allow to wrap rod elements with reduced risk of incomplete closure of the wrapper.

[0075] The rod element may be a rod element for an aerosol-generating article. The rod element may be an aerosol-generating article.

[0076] The filling material may be a porous material.

[0077] According to an embodiment of the invention there is provided a consumer article. The article may comprise a longitudinal axis extending between a mouth end and a distal end of the article. The article may comprise a rod element comprising a filling material. The filling material may be a porous filling material. The article may comprise a helical wrapper circumscribing the rod element. The helical wrapper may comprise at least one band of wrapping material extending helically along the longitudinal axis.

[0078] According to an embodiment of the invention there is provided a consumer article. The article comprises a longitudinal axis extending between a mouth end and a distal end of the article. The article comprises a rod element comprising a porous filling material. The article comprises a helical wrapper circumscribing the rod element. The helical wrapper comprises at least one band of wrapping material extending helically along the longitudinal axis.

[0079] The consumer article may be an aerosol-generating article comprising an aerosolforming substrate portion comprising an aerosol-forming substrate.

[0080] The helical wrapper may circumscribe both the rod element and the aerosol-forming substrate portion. The helical wrapper may circumscribe only the rod element comprising the filling material. The rod element with the helical wrapper may be a mouthpiece filter.

[0081] The filling material may be a porous material. The porous material may be selected from a natural fiber material, a synthetic fiber material, and an open cell foam. The filling material may be a paper-based material with open-cell structure. The filling material may be a paper-based open-cell foam. The filling material may be a filter material. The filling material may be a filter material selected from those known to be used as filter materials for an aerosolgenerating article, for example used in a mouthpiece filter of an aerosol-generating article.

[0082] The filling material may be provided in form of a web, a band, or a ribbon. For example, the filling material may be a flat band which is gathered within the rod element.

[0083] The filling material may be a porous material provided in form of a web, a band, or a ribbon.

[0084] As used herein, the term “porous material” may refer to a material which either is porous by itself, or which forms air channels when shaped into a rod.

[0085] The filling material may be an elastic material. The filling material may be an elastic material which sustains limited transversal compression. The filling material may be elastic and may exhibit a transversal expansion downstream of the hollow winding guide. Thereby, the filling material may compensate for the wall thickness of the hollow winding guide and may expand to fully fill the space within the helical wrapper downstream of the hollow winding guide.

[0086] The at least one band of wrapping material may be made of a cellulose-based material. The at least one band of wrapping material may be made of a paper-based material. The at least one band of wrapping material may be made from a tipping paper material known from the tobacco industry.

[0087] As used herein, the term “helical wrapper” refers to a wrapping material made of one or more bands of wrapping material which extend in a spiral around a rod of filling material. The rod of filling material is therefore “helically wrapped”.

[0088] The term “endless helically wrapped rod” refers to the helically wrapped rod before being cut into individual helically wrapped rod elements.

[0089] With the terms "upstream" or "downstream", reference is herein made to the processing direction of the helically wrapped rod elements. Generally, manufacturing of the rod elements takes place in a downstream direction from the upstream end towards the downstream end of the apparatus or a part thereof.

[0090] The downstream direction is a direction from the upstream end to the downstream end. The downstream direction is the processing or manufacturing direction. The upstream direction is the opposing direction from the downstream end towards the upstream end.

[0091] As used herein, the term “winding around the hollow winding guide” may refer to “winding around an outer side of the hollow winding guide”. As used herein, the term “winding around the hollow winding guide” may be understood to exclude “winding within a hollow winding guide”.

[0092] Below, there is provided a non-exhaustive list of non-limiting examples. Any one or more of the features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0093] Example E1 : An apparatus for manufacturing a rod element with a helical wrapper, the apparatus comprising a hollow winding guide; a filling unit configured for continuously filling a filling material into an upstream end of the hollow winding guide; a band provision unit configured for guiding at least one band of wrapping material towards the hollow winding guide; and a winding unit configured for winding the at least one band of wrapping material around the hollow winding guide to provide an endless helically wrapped rod.

[0094] Example E2: The apparatus according to Example E1 , wherein the rod element is a rod element for an aerosol-generating article, or wherein the rod element is an aerosolgenerating article.

[0095] Example E3: The apparatus according to Example E1 or Example E2, wherein the filling unit is configured for continuously filling a porous material into the upstream end of the hollow winding guide.

[0096] Example E4: The apparatus according to any of the preceding examples, wherein the filling unit comprises an inside arm extending into an upstream portion of the hollow winding guide, the inside arm being configured to conduct a to-and-fro motion with respect to a longitudinal axis of the hollow winding guide.

[0097] Example E5: The apparatus according to Example E4, wherein the inside arm is connected to a piston to allow the to-and-fro motion of the inside arm.

[0098] Example E6: The apparatus according to Example E4 or Example E5, wherein the inside arm is configured as a cylindrical element comprising at least one protruding feature on the cylindrical surface. Example E7: The apparatus according to Example E6, wherein the at least one protruding feature is configured as at least one barb.

[0099] Example E8: The apparatus according to Example E6, wherein the at least one protruding feature is configured as at least one movable rib, the at least one movable rib being movable between a first position transversal to a longitudinal axis of the inside arm when the inside arm moves in a direction towards the hollow winding guide, and a second position in alignment with the longitudinal axis of the inside arm when the inside arm moves in a direction away from the hollow winding guide.

[0100] Example E9: The apparatus according to any of Examples E4 to E8, wherein the inside arm has a pointed end.

[0101] Example E10: The apparatus according to any of Examples E1 to E3, wherein the filling unit comprises a rotating screw conveyer extending into at least an upstream portion of the hollow winding guide.

[0102] Example E11 : The apparatus according to any of Example E1 to E3, wherein the filling unit comprises one or more roller pairs configured for transporting a band of the filling material into the hollow winding guide.

[0103] Example E12: The apparatus according to Example E11 , wherein the filling unit comprises a first roller pair configured for pushing the band of filling material into a converging tool and a second roller pair downstream of the converging tool configured for pulling the band of filling material out of the converging tool and further into the hollow winding guide.

[0104] Example E13: The apparatus according to any of the preceding examples, wherein the hollow winding guide is tube-shaped.

[0105] Example E14: The apparatus according to Example E13, wherein a thickness of a sidewall of the tube-shaped hollow winding guide is between 0.5 millimeter and 1.5 millimeters.

[0106] Example E15: The apparatus according to Example E13 or Example E14, wherein a length of the tube-shaped hollow winding guide is between 1 meter and 3 meters.

[0107] Example E16: The apparatus according to any of Examples E13 to E15, wherein the tube-shaped hollow winding guide is configured as a stainless steel tube.

[0108] Example E17: The apparatus according to any of the preceding examples, wherein the hollow winding guide comprises a funnel-shaped opening.

[0109] Example E18: The apparatus according to any of the preceding examples, wherein the hollow winding guide comprises a glue channel, the glue channel comprising an inlet opening configured for receiving glue and an outlet opening.

[0110] Example E19: The apparatus according to Example E18, wherein the outlet opening of the glue channel is arranged within the hollow winding guide, or is arranged at a downstream end of the hollow winding guide, or wherein the glue channel extends past a main body of the hollow winding guide such that the outlet opening of the glue channel is arranged downstream of the end of the main body.

[0111] Example E20: The apparatus according to Example E18 or Example E19, comprising a heating station configured for heating the endless helically wrapped rod, the heating station being arranged downstream of the hollow winding guide.

[0112] Example E21 : The apparatus according to any of Example E18 to E20, comprising a glue pump configured for injecting glue into the inlet opening of the glue channel.

[0113] Example E22: The apparatus according to any of the preceding examples, wherein the hollow winding guide has a low friction surface, preferably wherein the hollow winding guide has a diamond-like carbon coating.

[0114] Example E23: The apparatus according to any of the preceding examples, wherein the winding unit is configured for winding the at least one band of wrapping material around the hollow winding guide, such that the band does not overlap itself.

[0115] Example E24: The apparatus according to Example E23, wherein the winding unit is configured for winding the at least one band of wrapping material around the hollow winding guide, such that a pitch of a full helical turn of a band of wrapping material around the winding guide is equal to a width of said band of wrapping material.

[0116] Example E25: The apparatus according to any of the preceding examples, wherein the winding unit is configured for winding a plurality of bands of wrapping material around the hollow winding guide, preferably two bands, three bands, or four bands.

[0117] Example E26: The apparatus according to Example E25, wherein the winding unit is configured for winding the plurality of bands of wrapping material around the hollow winding guide, such that neighboring bands overlap each other.

[0118] Example E27: The apparatus according to Example E25 or Example E26, wherein the plurality of bands of wrapping material comprises an inner band and one or more outer bands, wherein the winding unit is configured for winding the one or more outer bands around the inner band, and wherein the apparatus comprises a gluing unit configured to apply glue onto the one or more outer bands and not to apply glue onto the inner band.

[0119] Example E28: The apparatus according to any of the preceding examples, wherein the winding unit comprises an endless belt configured for continuously rotating and pulling the endless helically wrapped rod along a downstream direction, wherein the endless belt is driven by two rotating cylinders being arranged vertically to a longitudinal axis of the hollow winding guide, and wherein the endless belt is helically arranged around the endless helically wrapped rod. Example E29: The apparatus according to any of the preceding examples, comprising a cutting unit arranged downstream of the hollow winding guide, the cutting unit being configured to cut the endless helically wrapped rod into helically wrapped rod elements.

[0120] Example E30: The apparatus according to Example E29, wherein the cutting unit is configured to transversally cut the entire cross-section of the endless helically wrapped rod.

[0121] Example E31 : The apparatus according to Example E29 or Example E30, wherein the cutting unit comprises a rotating knife.

[0122] Example E32: The apparatus according to any of Examples E29 to E31 , wherein the cutting unit comprises an array of circular knifes.

[0123] Example E33: The apparatus according to any of Examples E29 to E32, wherein the cutting unit comprises a moving support configured for holding the cut helically wrapped rod elements.

[0124] Example E34: The apparatus according to any of the preceding examples, wherein the hollow winding guide is fixed, or wherein the apparatus comprises a motor configured for rotating the hollow winding guide around its longitudinal axis.

[0125] Example E35: The apparatus according to any of the preceding examples, comprising a gluing unit, the gluing unit being configured to apply glue to at least one band of wrapping material before being wound around the hollow winding guide.

[0126] Example E36: The apparatus according to Example E35, wherein the gluing unit comprises one or both of a glue roller and a glue nozzle configured for applying the glue.

[0127] Example E37: The apparatus according to Example E35 or Example E36, wherein the gluing unit is configured to apply one or both of ethylene-vinyl acetate-based glue and polyvinyl acetate glue.

[0128] Example E38: A method for manufacturing a rod element with a helical wrapper, the method comprising providing a hollow winding guide; helically winding at least one band of wrapping material around the hollow winding guide to form an endless helically wrapped rod; and filling a filling material into the hollow winding guide such that the endless helically wrapped rod is filled with the filling material.

[0129] Example E39: The method according to Example E38, wherein the rod element is a rod element for an aerosol-generating article, or wherein the rod element is an aerosolgenerating article.

[0130] Example E40: The method according to Example E38 or Example E39, wherein the filling material is a porous material.

[0131] Example E41 : A consumer article, comprising a longitudinal axis extending between a mouth end and a distal end of the article; a rod element comprising a filling material; and a helical wrapper circumscribing the rod element, wherein the helical wrapper comprises at least one band of wrapping material extending helically along the longitudinal axis.

[0132] Example E42: The consumer article according to Example E41 , wherein the consumer article is an aerosol-generating article comprising an aerosol-forming substrate portion comprising an aerosol-forming substrate.

[0133] Example E43: The aerosol-generating article according to Example E42, wherein the helical wrapper circumscribes both the rod element and the aerosol-forming substrate portion, or wherein the helical wrapper circumscribes only the rod element comprising the filling material.

[0134] Example E44: The consumer article according to any of Examples E40 to E43, wherein the filling material is a porous material, preferably wherein the porous material is selected from a natural fiber material, a synthetic fiber material, and an open cell foam.

[0135] Example E45: The consumer article according to Example E44, wherein the filling material is a porous material provided in form of a web, a band, or a ribbon.

[0136] Features described in relation to one embodiment may equally be applied to other embodiments of the invention.

[0137] The invention will be further described, by way of example only, with reference to the accompanying drawings in which:

[0138] Figs. 1a and 1b show helical wrapping around a hollow winding guide;

[0139] Fig. 2 shows a hollow winding guide with an advancing mechanism;

[0140] Figs. 3a to 3d show hollow winding guides;

[0141] Fig. 4 shows an apparatus for manufacturing a rod element with a helical wrapper;

[0142] Fig. 5 shows an apparatus for manufacturing a rod element with a helical wrapper;

[0143] Figs. 6a to 6c show filling units;

[0144] Fig. 7 shows a filling unit;

[0145] Figs. 8a and 8b show a filling unit; and

[0146] Fig. 9 shows an apparatus for manufacturing a rod element with a helical wrapper.

[0147] Fig. 1a schematically shows winding of a single band of wrapping material 100 in a spiral 116 around a tubular hollow winding guide 10 to form a helical wrapper 107. The incoming angle of the band 100 as well as the spiral step are chosen such that the band 100 does not overlap itself once wound and follows a helical side-to-side trajectory. Above the winding guide 10, a cut view 101 of the helically wound band 100 is indicated. The winding unit is thus configured for winding the band of wrapping material 100 around the hollow winding guide 10 such that a pitch of a full helical turn of the band of wrapping material 100 around the winding guide 10 is equal to a width of said band of wrapping material 100.

[0148] Fig. 1b schematically shows helically 116 winding of a plurality of bands of wrapping material, for example an inner band 100 and three outer bands 102, 104, 106, around a tubular hollow winding guide 10. In the embodiment shown, all bands have the same width. Each band is not overlapping itself, but follows a side-to-side helical trajectory. The different bands are partially overlapping one another.

[0149] A cut view 101 of the layers of the bands 100, 102, 104, 106 forming the helical wrapper

[0150] 107 is indicated above the winding guide 10. The cut view 101 shows how the four bands create progressively four layers 100, 102, 104, 106, one above the other. This progressive layering can also be seen around the winding guide 10.

[0151] The winding unit is thus configured for winding the plurality of bands of wrapping material 100, 102, 104, 106 around the hollow winding guide 10 such that neighboring bands overlap each other. Each band overlaps at most one neighboring band and is overlapped by at most one neighboring band. The inner band 100 does not overlap another band and is overlapped by its neighboring band 102. Band 102 is overlapped by its neighboring band 104. Band 104 is overlapped by the outermost band 106. The outermost band 106 is not overlapped by another band.

[0152] The outer bands 102, 104 106 may be fed from another direction as the inner band 100 as indicated by darker greyscale and curved arrows in Fig. 1b. For example, the innermost band 100 may be incoming from one side of the winding guide 10 while the other bands 102, 104, 106 come from the other side passing a gluing unit to provide an adhesive coating that covers their inner surfaces.

[0153] Fig. 2 shows an advancing mechanism for an apparatus for manufacturing a rod element with a helical wrapper. The advancing mechanism is configured for advancing the endless helically wrapped rod 108 along a downstream direction 110. The advancing mechanism may form part of the winding unit and comprises an endless belt 20. The endless belt 20 is configured for continuously rotating and pulling the endless helically wrapped rod

[0154] 108 along the downstream direction 110. The endless belt 20 is driven by two rotating cylinders 22. The two rotating cylinders 22 are arranged vertically to a longitudinal axis of the hollow winding guide 10. The endless belt 20 is helically arranged around the endless helically wrapped rod 108. The advancing mechanism thereby pulls the at least one band of wrapping material 100, 102, 104, 106 in spiral along the winding guide 10.

[0155] The winding guide 10 may be fixed, or may be connected to a motor which makes it rotate around its longitudinal axis and in the direction of the winding.

[0156] Figs. 3a to 3c show cut views of hollow winding guides 10. Fig. 3d shows a crosssection along line Z-Z’ of the hollow winding guides 10 of Figs. 3a to 3c. The hollow winding guides 10 of Figs. 3a to 3c each comprises a glue channel 14. The glue channel 14 comprises an inlet opening 16 configured for receiving glue and an outlet opening 18. The inlet opening 16 is arranged at the upstream end of the hollow winding guide 10. In the embodiment of Fig. 3a, the outlet opening 18 of the glue channel 14 is arranged at a downstream end of the hollow winding guide 10. In the embodiment of Fig. 3b, the outlet opening 18 of the glue channel 14 is arranged within the hollow winding guide 10. In the embodiment of Fig. 3c, the glue channel 14 extends past the main body of the hollow winding guide 10 such that the outlet opening 18 of the glue channel 14 is arranged downstream of the end of the main body.

[0157] In all three embodiments of Figs. 3a to 3c, the glue exiting the glue channel 14, may penetrate an area between the filling material and the inner surface of the wrapped bands of wrapping material, so that the filling material and the inner surface of the helical wrapper 107 get glued together.

[0158] Fig. 4 shows a side cut view of an apparatus for manufacturing a rod element with a helical wrapper. The apparatus comprises a hollow winding guide 10. The apparatus comprises a filling unit (not shown in Fig. 4). The filling unit may be a filling unit as shown in any of Figs. 6 to 9. The filling unit is configured for continuously filling a porous filling material 120 into an upstream end of the hollow winding guide 10. The apparatus comprises a band provision unit. The band provision unit is configured for guiding at least one band of wrapping material 100, 102, 104, 106 towards the hollow winding guide 10. The apparatus comprises a winding unit. The winding unit is configured for winding the at least one band of wrapping material 100, 102, 104, 106 around the hollow winding guide 10 to provide an endless helically wrapped rod 108.

[0159] The hollow winding guide 10 may be a hollow winding guide 10 as shown in any one of Figs. 3a to 3c. The apparatus of Fig. 4 comprises a glue pump 30 configured for injecting glue into the inlet opening 16 of the glue channel 14. The apparatus comprises a heating station 32. The heating station 32 is arranged downstream of the hollow winding guide 10. The heating station 32 is configured for heating the endless helically wrapped rod 108.

[0160] The apparatus of Fig. 4 comprises an advancing mechanism configured for advancing the endless helically wrapped rod 108 along a downstream direction 110. The advancing mechanism comprises two rotating cylinders 22 for pulling the endless helically wrapped rod 108 along the downstream direction 110. The advancing mechanism may be an advancing mechanism comprising an endless belt 20 as shown in Fig. 2.

[0161] The apparatus of Fig. 4 comprises a cutting unit 40 arranged downstream of the hollow winding guide 10. The cutting unit 40 is configured to cut the endless helically wrapped rod 108 into helically wrapped rod elements. Fig. 5 shows an apparatus for manufacturing a rod element with a helical wrapper. The apparatus comprises a hollow winding guide 10. The apparatus comprises a filling unit. The filling unit is configured for continuously filling a porous filling material 120 into an upstream end of the hollow winding guide 10. The filling unit comprises an inside arm 50. The inside arm 50 extends into an upstream portion of the hollow winding guide 10. The inside arm 50 is configured to conduct a to-and-fro motion 52 with respect to a longitudinal axis of the hollow winding guide 10. The inside arm 50 is connected to a piston 54 to allow the to-and-fro motion of the inside arm 50.

[0162] The apparatus of Fig. 5 comprises a band provision unit. The band provision unit is configured for guiding at least one band of wrapping material 100, 102, 104 towards the hollow winding guide 10. The bands are provided from bobbins 34. Outer bands 102, 104 may pass a gluing station 36 on their way from the bobbins 34 to the hollow winding guide 10.

[0163] The apparatus of Fig. 5 comprises a winding unit. The winding unit is configured for winding the bands of wrapping material 100, 102, 104 around the hollow winding guide 10 to provide an endless helically wrapped rod 108.

[0164] The hollow winding guide 10 may be a hollow winding guide 10 as shown in any one of Figs. 3a to 3c. The apparatus of Fig. 5 may comprise a heating station 32 configured for heating the endless helically wrapped rod 108 arranged downstream of the hollow winding guide 10.

[0165] The apparatus of Fig. 5 comprises an advancing mechanism configured for advancing the endless helically wrapped rod 108 along a downstream direction 110. The advancing mechanism comprises two rotating cylinders 22 for pulling the endless helically wrapped rod 108 along the downstream direction 110. The advancing mechanism is an advancing mechanism comprising an endless belt 20 as shown in Fig. 2.

[0166] The apparatus of Fig. 5 comprises a cutting unit 40 arranged downstream of the hollow winding guide 10. The cutting unit 40 is configured to cut the endless helically wrapped rod 108 into helically wrapped rod elements 109. The cutting unit 40 may be configured to transversally cut the entire cross-section of the endless helically wrapped rod 108. The cutting unit 40 may comprise a rotating knife as schematically indicated in Fig. 5.

[0167] Figs. 6a to 6c show side cut views of parts of filling units.

[0168] Fig. 6a shows a side cut view of an inside arm 50 of a filling unit. The inside arm 50 is configured as a cylindrical element comprising at least one protruding feature on the cylindrical surface. The protruding feature is configured as a cone-shaped protrusion around the cylindrical axis of the inside arm 50. A base 56 of the cone-shaped protrusion faces towards the downstream end of the hollow winding guide 10 when the inside arm 50 is inserted into the hollow winding guide 10. Thereby, the base 56 helps to push the filing material 120 into the hollow winding guide 10 along the downstream direction 110 when the inside arm 50 moves in the downstream direction 110. When the inside arm 50 moves back in the upstream direction 112, a smoother cone surface 58 helps retracting the inside arm 50 without pulling back the filling material 120.

[0169] Figs. 6b and 6c show a filling unit with an inside arm 50 with at least one movable rib 60, for example two movable ribs 60 arranged on opposing sides of the inside arm 50. The inside arm 50 extends into the hollow winding guide 10 which, in turn, is surrounded by the helical wrapper 107 formed by winding the at least one band of material around the hollow winding guide by 10 by the winding unit.

[0170] Each of the at least one movable ribs 60 is movable between a first position and a second position. In the first position shown in Fig. 6b, the movable ribs 60 are arranged transversal to a longitudinal axis of the inside arm 50. The movable ribs 60 are configured to be in the first position when the inside arm 50 moves in a direction towards the hollow winding guide 10, i.e., in the downstream direction 110. In the second position shown in Fig. 6c, the movable ribs 60 are arranged in alignment with the longitudinal axis of the inside arm 50. The movable ribs 60 are configured to be in the second position when the inside arm 50 moves in a direction away from the hollow winding guide 10, i.e., in the upstream direction 112.

[0171] Fig. 7 shows a side cut view of a downstream portion of the hollow winding guide 10 being helically wrapped by the helical wrapper 107. The inside arm 50 of the filling unit may have a pointed end 62 extending nearly up to a downstream end of the hollow winding guide 10.

[0172] In an upstream area “A”, the inside arm 50 is inside the winding guide 10, in the center of the compressed filling material 120, which is moving downstream thanks to the pushing movements of the inside arm 50. Going downstream, there is an area “B” without the inside arm 50, then an area “C” without the winding guide 10. The natural expansion of the compressed porous filling material 120 may progressively fill an empty space 114, generating, at the downstream end before the cutting unit 40 shown in downstream area “D”, a fully filled helically wrapped rod 108.

[0173] The natural expansion of the filling material 120 comes after its compression inside the hollow winding guide 10 (due to the piston action of the inside arm 50) and may create a strong friction bonding between the filling material 120 and the wall of the helical wrapper 107, while not deforming the tubular wrapper wall as this expansion happens after the end of the hollow winding guide 10, when the wound bands of wrapping material have already achieved a strong and solid tubular shape.

[0174] According to other embodiments, the winding guide 10 may end upstream of the downstream end of the inside arm 50.

[0175] Fig. 8a shows a side cut view of the hollow winding guide 10. The winding unit helically winds the at least one band of wrapping material 100, 102, 104, 106 around the hollow winding guide 10 to form the helical wrapper 107. The filling unit comprises a rotating screw conveyer 62 extending into the hollow winding guide 10. The rotating screw conveyor 62 pushes the filling material 120 into the hollow winding guide 10.

[0176] Preferably, the rotation of the rotating screw conveyor 62 is in the same direction of rotation as the rotation of the helical wrapper 107 around the hollow winding guide 10. When the filling material 120 exits from the hollow winding guide, both the filling material 120 and the helical wrapper 107 may thereby have somehow the same kind of rotation around the longitudinal axis. The rotating screw conveyor 62 may create a helical movement of the filling material which may be configured to meet the helical movement of the wrapper 107.

[0177] Fig. 8b shows a perspective view of the rotating screw conveyer 62 within the hollow winding guide 10. A part of the side wall of the hollow winding guide 10 is not shown for illustrative purposes, such that the rotating screw conveyer 62 within the hollow winding guide 10 is visible.

[0178] Fig. 9 shows an apparatus for manufacturing a rod element with a helical wrapper. The apparatus comprises a hollow winding guide 10. The apparatus comprises a filling unit. The filling unit is configured for continuously filling a porous filling material 120 into an upstream end of the hollow winding guide 10. The filling material 120 is pulled from a bobbin 34.

[0179] The filling unit comprises two roller pairs 70, 74 configured for transporting a band of the filling material 120 into the hollow winding guide 10. The filling unit comprises a first roller pair 70 configured for pushing the band of filling material 120 into a funnel-shaped converging tool 72. The filling unit comprises a second roller pair 74 downstream of the converging tool 72 configured for pulling the band of filling material 120 out of the converging tool 72 and further into the hollow winding guide 10.

[0180] At the exit of the converging tool 72, a temporary continuous rod is formed, and before it expands too much, the second roller pair 74 pushes this continuous rod into the hollow winding guide 10. The hollow winding guide 10 may comprise a funnel-shaped upstream end.

[0181] The apparatus of Fig. 9 comprises a band provision unit. The band provision unit is configured for guiding at least one band of wrapping material 100, 102 towards the hollow winding guide 10. The one or more bands 100, 102 are provided from bobbins 34.

[0182] The apparatus of Fig. 9 comprises a winding unit. The winding unit is configured for winding the bands of wrapping material 100, 102 around the hollow winding guide 10 to provide an endless helically wrapped rod 108. The hollow winding guide 10 may be a hollow winding guide 10 as shown in any one of Figs. 3a to 3c. The apparatus of Fig. 9 may comprise a heating station 32 configured for heating the endless helically wrapped rod 108 arranged downstream of the hollow winding guide 10. The apparatus of Fig. 9 may comprise an advancing mechanism (not shown in Fig. 9) configured for advancing the endless helically wrapped rod 108 along a downstream direction 110.

[0183] The apparatus of Fig. 9 comprises a cutting unit 40 arranged downstream of the hollow winding guide 10. The cutting unit 40 is configured to cut the endless helically wrapped rod 108 into helically wrapped rod elements 109. The cutting unit 40 may be configured to transversally cut the entire cross-section of the endless helically wrapped rod 108. The cutting unit 40 may comprise a rotating knife as schematically indicated in Fig. 9.

Claims

CLAIMS1. An apparatus for manufacturing a rod element with a helical wrapper, the apparatus comprising a hollow winding guide; a filling unit configured for continuously filling a porous filling material into an upstream end of the hollow winding guide; a band provision unit configured for guiding at least one band of wrapping material towards the hollow winding guide; and a winding unit configured for winding the at least one band of wrapping material around the hollow winding guide to provide an endless helically wrapped rod.

2. The apparatus according to claim 1 , wherein the rod element is a rod element for an aerosol-generating article, or wherein the rod element is an aerosol-generating article.

3. The apparatus according to claim 1 or claim 2, wherein the filling unit comprises an inside arm extending into an upstream portion of the hollow winding guide, the inside arm being configured to conduct a to-and-fro motion with respect to a longitudinal axis of the hollow winding guide.

4. The apparatus according to claim 3, wherein the inside arm is configured as a cylindrical element comprising at least one protruding feature on the cylindrical surface.

5. The apparatus according to claim 4, wherein the at least one protruding feature is configured as at least one movable rib, the at least one movable rib being movable between a first position transversal to a longitudinal axis of the inside arm when the inside arm moves in a direction towards the hollow winding guide, and a second position in alignment with the longitudinal axis of the inside arm when the inside arm moves in a direction away from the hollow winding guide.

6. The apparatus according to any of the preceding claims, wherein the hollow winding guide is tube-shaped.

7. The apparatus according to claim 6, wherein a thickness of a sidewall of the tube-shaped hollow winding guide is between 0.5 millimeter and 1.5 millimeters.

8. The apparatus according to claim 6 or claim 7, wherein a length of the tubeshaped hollow winding guide is between 1 meter and 3 meters.

9. The apparatus according to any of the preceding claims, wherein the hollow winding guide comprises a funnel-shaped opening.

10. The apparatus according to any of the preceding claims, wherein the hollow winding guide comprises a glue channel, the glue channel comprising an inlet opening configured for receiving glue and an outlet opening.

11. The apparatus according to claim 10, wherein the outlet opening of the glue channel is arranged within the hollow winding guide, or is arranged at a downstream end of the hollow winding guide, or wherein the glue channel extends past a main body of the hollow winding guide such that the outlet opening of the glue channel is arranged downstream of the end of the main body.

12. The apparatus according to any of the preceding claims, wherein the winding unit comprises an endless belt configured for continuously rotating and pulling the endless helically wrapped rod along a downstream direction, wherein the endless belt is driven by two rotating cylinders being arranged vertically to a longitudinal axis of the hollow winding guide, and wherein the endless belt is helically arranged around the endless helically wrapped rod.

13. The apparatus according to any of the preceding claims, comprising a cutting unit arranged downstream of the hollow winding guide, wherein the cutting unit is configured to cut the endless helically wrapped rod into helically wrapped rod elements, and wherein the cutting unit is configured to transversally cut the entire cross-section of the endless helically wrapped rod.

14. A method for manufacturing a rod element with a helical wrapper, the method comprising providing a hollow winding guide; helically winding at least one band of wrapping material around the hollow winding guide to form an endless helically wrapped rod; and filling a porous filling material into the hollow winding guide such that the endless helically wrapped rod is filled with the porous filling material.

15. A consumer article, comprising a longitudinal axis extending between a mouth end and a distal end of the article; a rod element comprising a porous filling material, the rod element being a mouthpiece filter; and a helical wrapper circumscribing the rod element, wherein the helical wrapper comprises at least one band of wrapping material extending helically along the longitudinal axis.

16. The consumer article according to claim 15, wherein the consumer article is an aerosol-generating article, wherein the aerosol-generating article comprises an aerosolforming substrate portion comprising an aerosol-forming substrate, and wherein the helical wrapper circumscribes only the rod element.

Images