Aerosol-forming cartridge comprising a tobacco-containing material

Abstract

There is provided an aerosol-forming cartridge for an electrically operated aerosol-generating system. The cartridge includes a base layer and at least one aerosol-forming substrate disposed on the base layer and including a tobacco-containing material with volatile tobacco flavor compounds that are releasable from the aerosol-forming substrate. The base layer and the at least one aerosol-forming substrate are in contact at a contact surface, which is substantially planar.

Claims

1. An aerosol-forming cartridge for an electrically operated aerosol-generating system, the cartridge comprising: a base layer; and at least one aerosol-forming substrate disposed on the base layer and comprising a tobacco-containing material with volatile tobacco flavour compounds that are releasable from the at least one aerosol-forming substrate, wherein the base layer and the at least one aerosol-forming substrate are in contact at a first contact surface, which is substantially planar.

2. The aerosol-forming cartridge of claim 1, wherein one or both of the base layer and the at least one aerosol-forming substrate is substantially flat.

3. The aerosol-forming cartridge of claim 1, wherein the base layer comprises at least one cavity, and wherein the at least one aerosol-forming substrate is held in the at least one cavity.

4. The aerosol-forming cartridge of claim 1, wherein the at least one aerosol-forming substrate comprises a plurality of aerosol-forming substrates disposed separately on the base layer.

5. The aerosol-forming cartridge of claim 4, wherein the base layer comprises a plurality of cavities, and wherein each of the plurality of aerosol-forming substrates is held in a cavity of the plurality of cavities.

6. The aerosol-forming cartridge of claim 1, further comprising an electric heater including at least one heating element configured to heat the at least one aerosol-forming substrate, wherein a second contact surface between the electric heater and one or both of the base layer and the at least one aerosol-forming substrate is substantially planar and substantially parallel to the first contact surface between the base layer and the at least one aerosol-forming substrate.

7. The aerosol-forming cartridge of claim 6, wherein the at least one aerosol-forming substrate comprises a plurality of aerosol-forming substrates disposed separately on the base layer, and wherein the electric heater comprises a plurality of heating elements each configured to heat a different one of the plurality of aerosol-forming substrates.

8. The aerosol-forming cartridge of claim 1, further comprising an integral mouthpiece portion.

9. The aerosol-forming cartridge of claim 8, wherein the cartridge is configured such that a resistance-to-draw at a downstream end of the mouthpiece portion is from about 50 mmWG to about 130 mmWG.

10. The aerosol-forming cartridge of claim 8, wherein the cartridge is configured such that a resistance-to-draw at a downstream end of the mouthpiece portion is from about 95 mmWG to about 105 mmWG.

11. An electrically operated aerosol-forming system, comprising: an aerosol-forming cartridge comprising: a base layer, and at least one aerosol-forming substrate disposed on the base layer and comprising a tobacco-containing material with volatile tobacco flavour compounds that are releasable from the at least one aerosol-forming substrate, wherein the base layer and the at least one aerosol-forming substrate are in contact at a first contact surface, which is substantially planar; an electric vaporiser configured to vaporise the at least one aerosol-forming substrate; and an aerosol-generating device comprising: a main body defining a slot-shaped receptacle configured to removably receive the aerosol-forming cartridge, and an electric power supply configured to supply power to the electric vaporiser.

12. A method of manufacturing an aerosol-forming cartridge for an electrically operated aerosol-generating system, the method comprising: providing a base layer; and placing at least one aerosol-forming substrate on the base layer such that the base layer and the at least one aerosol-forming substrate are joined at a first contact surface, which is substantially planar, wherein the at least one aerosol-forming substrate comprises a tobacco-containing material with volatile tobacco flavour compounds, which are released from the at least one aerosol-forming substrate upon heating.

13. The method of claim 12, further comprising forming at least one cavity in the base layer, wherein the placing the at least one aerosol-forming substrate on the base layer further comprises placing the at least one aerosol-forming substrate in the at least one cavity.

14. The method of claim 12, wherein the providing the base layer comprises feeding a web of base layer foil from a bobbin to an assembly line and cutting the web of base layer foil transversely to form individual base layers.

15. The method of claim 12, further comprising attaching an electric heater to the base layer such that the electric heater and the base layer are in contact at a second contact surface, which is substantially planar and is substantially parallel to the first contact surface between the base layer and the at least one aerosol-forming substrate.

16. The method of claim 15, wherein the attaching the electric heater comprises feeding a web of electric heater foil from a bobbin to an assembly line and cutting the web of electric heater foil transversely to form individual electric heaters.

17. The method of claim 16, further comprising forming a plurality of aerosol-forming cartridges in parallel, wherein the web of electric heater foil has a width from about two times to about 50 times greater than a width of each aerosol-forming cartridge of the plurality of aerosol-forming cartridges.

18. The method of claim 16, wherein two or more webs of foil from which the aerosol-forming cartridge is made are laminated together.

19. The method of claim 16, wherein the web of electric heater foil comprises a web of electrically insulating substrate foil to which a plurality of heating elements is attached.

20. The method of claim 19, further comprising forming a plurality of aerosol-forming cartridges in parallel, wherein the web of base layer foil has a width from about two times to about 50 times greater than a width of each aerosol-forming cartridge of the plurality of aerosol-forming cartridges.

Description

(1) The invention will now be further described, by way of example only, with reference to the accompanying drawings in which:

(2) FIGS. 1A, 1B and 1C show a schematic illustration of an aerosol-generating system comprising an aerosol-forming cartridge in accordance with the present invention inserted into an electrically operated aerosol-generating device;

(3) FIGS. 2A and 2B show a first embodiment of an aerosol-forming cartridge in accordance with the present invention, where FIG. 2A is a perspective view and FIG. 2B is an exploded view of the cartridge;

(4) FIGS. 3A and 3B show a second embodiment of an aerosol-forming cartridge in accordance with the present invention, where FIG. 3A is a perspective view and FIG. 3B is an exploded view of the cartridge;

(5) FIGS. 4A and 4B show a third embodiment of an aerosol-forming cartridge in accordance with the present invention, where FIG. 4A is a perspective view and FIG. 4B is an exploded view of the cartridge;

(6) FIG. 5 shows a schematic illustration of a manufacturing process for making the aerosol-forming cartridge of FIGS. 2A and 2B; and

(7) FIG. 6 shows a schematic illustration of a manufacturing process for making the aerosol-forming cartridge of FIGS. 3A and 3B.

(8) FIGS. 1A and 1B show an aerosol-generating device 10 and a separate, removable aerosol-forming cartridge 20, which together form an aerosol-generating system. The device 10 is portable and has a size comparable to a conventional cigar or cigarette. The device 10 comprises a main body 11 and a removable mouthpiece portion 12. The main body 12 contains a battery 13, such as a lithium iron phosphate battery, electric circuitry 14 and a slot-shaped cavity 15. The mouthpiece portion 12 fits over the cartridge and is connected to the main body 11 by a releasable connecting means (not shown). The mouthpiece portion 12 can be removed (as shown in FIG. 1) to allow for insertion and removal of cartridges and is connected to the main body 11 when the system is to be used to generate aerosol, as will be described. The mouthpiece portion 12 comprises an air inlet 16 and an air outlet 17, each of which may comprise one or more orifices. In use, a user sucks or puffs on the air outlet 17 to draw air from the air inlet 16, through the mouthpiece portion 12 to the air outlet 17. A flow of air drawn through the mouthpiece portion 12 may be drawn past the cartridge 20 (as shown by the arrows marked as A in FIG. 2), or also through one or more air flow channels in the cartridge 20 (as indicated by the arrows marked as B in FIG. 2). The cavity 15 has a rectangular cross-section and is sized to receive at least part of the cartridge 20 to removably connect the device 10 and the cartridge 20. As used herein, the term removably connect means that the device and the cartridge can be coupled and uncoupled from one another without significant damage to either.

(9) FIG. 1C shows a schematic illustration of a connection between the device 10 and the cartridge 20 within the cavity 15, with the cartridge 20 shown as partially inserted and the arrow indicating the direction of insertion. Electrical contacts 18 are provided along a side portion and a bottom portion of the cavity 15 to provide an electrical connection between the electric circuitry 14 and the battery 13 with corresponding electrical contacts on the cartridge 20. Guide rails 19 are provided in the cavity 15 to assist with the correct positioning of the cartridge 20 within the cavity 15.

(10) FIGS. 2A and 2B show a first embodiment of aerosol-forming cartridge 220. The cartridge 220 is substantially flat and has a rectangular cross-section, although it could have any other suitable flat shape. The cartridge comprises a base layer 222, an aerosol-forming substrate 224 arranged on the base layer 222, a heater 226 positioned between the aerosol-forming substrate 224 and the base layer 222, a cover layer 228 fixed to the base layer 222 and over the aerosol-forming substrate 224, a protective foil 230 over the cover layer 228 and a top cover 232 fixed to the cover layer 228 and over the cover layer 228 and the protective foil 230. The base layer 222, aerosol-forming substrate 224, heater 226, cover layer 228, protective foil 230 and top cover 232 are all substantially flat and substantially parallel to each other. The contact surfaces between each of these components of the cartridge 220 are substantially planar and substantially parallel with each other.

(11) The base layer 222 has a cavity 234 defined on its top surface in which the heater 226 and the aerosol-forming substrate 224 are held. The aerosol-forming substrate 224 comprises a tobacco-containing material with volatile flavour compounds which are releasable from the aerosol-forming substrate 224 upon heating by the heater 226. In this example, the aerosol-forming substrate 224 is a substantially flat rectangular block of tobacco cast leaf.

(12) The heater 226 comprises a heating element 236 connected to electrical contacts 238. In this example, the heating element 236 and electrical contacts 238 are integral and the heater 226 is formed by stamping a sheet of stainless steel. The base layer 222 has two contact apertures 240 at its distal end into which the electrical contacts 238 extend. The electric contacts 238 are accessible from outside of the cartridge through the contact apertures 240.

(13) The cover layer 228 helps to keep the aerosol-forming substrate 224 in position on the base layer 222. The cover layer 228 has a permeable window 242 formed by a mesh grid 244 extending across an opening 246 in the cover layer 228. In use, aerosol released by the aerosol-forming substrate 224 passes through the permeable window 242. The cover layer 228 is sized to fit over the cavity 234 in the base layer 222. In this example, the cover layer 228 extends laterally beyond the cavity 234 and has substantially the same width and length as the base layer 222 so the edges of the cover layer 228 and the base layer 222 are generally aligned.

(14) The protective foil 230 is removably attached to the top of the cover layer 228 and over the permeable window 242 to seal the aerosol-forming substrate 224 within the cartridge 220. The protective foil 230 comprises a substantially impermeable sheet that is welded to the cover layer 228 but which can be easily peeled off. The sheet is welded to the cover layer 228 along a continuous sealing line formed of two continuous weld lines arranged side by side. The protective foil 230 acts to prevent substantial loss of volatile compounds from the aerosol-forming substrate 224 prior to use of the cartridge 220. In this example, the protective foil 230 is formed from a flexible multilayer polymer sheet. A tab 248 is provided at the free end of the protective foil 230 to allow a user to grasp the protective foil 230 to peel it off from over the permeable window 242.

(15) The tab 248 is formed by an extension of the protective foil 230 and extends beyond the edge of the top cover 232. To facilitate removal, the protective foil 230 is folded over itself at a transverse fold line 249 such that the protective foil 230 is divided into a first portion 230A, which is attached to the cover layer 228 by the continuous sealing line, and a second portion 230B, which extends longitudinally from the fold line 249 to the tab 248. The section portion 230B lies flat against the first portion 230A so that the first and second portions 230A, 230B are substantially co-planar. With this arrangement, the protective foil 230 can be removed by pulling the tab 248 longitudinally to peel the first portion 230A away from the cover layer 228 at the fold line 249.

(16) It will be apparent to one of ordinary skill in the art that, although welding is described as the method to secure the removable protective foil 230 to the cover layer 228, other methods familiar to those in the art may also be used including, but not limited to, heat sealing or adhesive, provided the protective foil 230 may easily be removed by a consumer.

(17) The top cover 232 is hollow and includes an air inlet 250 towards its distal end and an air outlet (not shown) at its proximal end. The air inlet 250 and the air outlet are connected by an air flow channel (not shown) which is defined between an internal wall surface (not shown) of the top cover 232 and the cover layer 228 below.

(18) During use, the protective foil 230 is removed by pulling the tab 248 in a longitudinal direction and away from the cartridge 220. Once the protective foil 230 has been removed, the aerosol-forming substrate 224 is in fluid communication with the air flow channel via the permeable window 242 in the cover layer 228. The cartridge 220 is then inserted into an aerosol-generating device, as shown in FIGS. 1A and 1B, so that the electrical contacts 238 connect with the corresponding electrical contacts in the cavity of the device. Electrical power is then provided by the device to the heater 226 of the cartridge to release aerosol from the aerosol-forming substrate. When a user sucks or puffs on the mouthpiece portion of the device, air is drawn from the air inlets in the mouthpiece, into the air inlet 250 of the top cover and through the air flow channel in the top cover, where it is mixed with the aerosol. The air and aerosol mixture is then drawn through the air outlet of the cartridge 220 to the outlet of the mouthpiece portion.

(19) Once the aerosol-forming substrate 224 has been consumed by a user, the cartridge is removed from the cavity of the device and replaced.

(20) FIGS. 3A and 3B show a second embodiment of aerosol-forming cartridge 320. In this example, the cartridge 320 is substantially flat and has a rectangular cross-section, although it could be any other suitable flat shape. The cartridge comprises a base layer 322 formed from an intermediate layer 323 and a heater 326 placed beneath and fixed to the intermediate layer 323. The cartridge also comprises a plurality of aerosol-forming substrates 324 arranged on the base layer 322, a cover layer 328 fixed to the base layer 322 and over the aerosol-forming substrates 324, a protective foil 330 over the cover layer 328 and a top cover 332 fixed to the cover layer 328 and over the cover layer 328 and the protective foil 330. The intermediate layer 323, aerosol-forming substrates 324, heater 326, cover layer 328, protective foil 330 and top cover 332 are all substantially flat and substantially parallel to each other. The contact surfaces between any two of these components 320 are substantially planar and substantially parallel.

(21) The intermediate layer 323 has a plurality of cavities 334 extending through its thickness, the bottoms of which are closed by the heater 326. The aerosol-forming substrates 324 are held in the plurality of cavities. In this example, the cavities 334 are substantially rectangular and arranged with their long sides substantially perpendicular to the longitudinal axis of the cartridge 320. The aerosol-forming substrates 324 each comprise a tobacco-containing material with volatile flavour compounds which are releasable upon heating by the heater 326. In this example, each aerosol-forming substrate is a substantially flat rectangular block of tobacco cast leaf.

(22) The heater 326 comprises a plurality of heating elements 336 connected to electrical contacts 338. In this example, the heater 326 is formed by disposing electrical contacts 338 and substantially rectangular heating elements 336 on an electrically insulating substrate foil 337 such that each of the heating elements 336 lies beneath an aerosol-forming substrate 324. The electrically insulating substrate foil 337 is sized to extend across the width and length of each cavity 334 to close off the bottom of the cavities 334. The electric contacts 338 extend along a side edge of the electrically insulating substrate foil 337 and are accessible from outside of the cartridge from underneath, since the heater 326 is the bottom layer of the cartridge 320. In this example, an electric contact 338 is provided for each of the plurality of heating elements 336. Thus, each heating element 336 can be powered separately, enabling each aerosol-forming substrate 324 to be heated separately. This enables sequential heating of the aerosol-forming substrates, for example to heat a fresh, or previously unheated, aerosol-forming substrate 324 for each predetermined aerosol delivery operation. In other embodiments, the heater may be external. That is, the heater is not provided in the cartridge but is adjacent to the cartridge when inserted in an aerosol-generating device. In such examples, a heat conductive substrate foil, such as aluminium foil, may be used in place of the heater.

(23) The cover layer 328 helps to keep the aerosol-forming substrates 324 in position in the cavities 334 of the base layer 322. The cover layer 328 has a permeable window 342 formed by a grid 344 extending across an opening 346 in the cover layer 328. In use, aerosol released by the aerosol-forming substrate 324 passes through the permeable window 342. The cover layer 328 is sized to fit over the cavities 334 in the base layer 322. In this example, the cover layer 328 extends laterally beyond the cavities 334 and has substantially the same width and length as the base layer 322 so the edges of the cover layer 328 and the base layer 322 are generally aligned.

(24) The protective foil 330 is removably attached to the top of the cover layer 328 and over the permeable window 342 to seal the aerosol-forming substrates 324 within the cavities 334. The protective foil 330 comprises a substantially impermeable sheet that is welded to the cover layer 328 but which can be easily peeled off. The sheet is welded to the cover layer 328 along a continuous sealing line formed of two continuous weld lines arranged side by side. The protective foil 330 acts to prevent substantial loss of volatile compounds from the aerosol-forming substrate 324 prior to use of the cartridge 320. In this example, the protective foil 330 is formed from a flexible multilayer polymer sheet. A tab 348 is provided at the free end of the protective foil 330 to allow a user to grasp the protective foil 330 to peel it off from over the permeable window 342. The tab 348 is formed by an extension of the protective foil 330 and extends beyond the edge of the top cover 332. To facilitate removal, the protective foil 330 is folded over itself at a transverse fold line 349 such that the protective foil 330 is divided into a first portion 330A, which is attached to the cover layer 328 by the continuous sealing line, and a second portion 330B, which extends longitudinally from the fold line 349 to the tab 348. The section portion 330B lies flat against the first portion 330A so that the first and second portions 330A, 330B are substantially co-planar. With this arrangement, the protective foil 330 can be removed by pulling the tab 348 longitudinally to peel the first portion 330A away from the cover layer 328 at the fold line 349. It will be apparent to one of ordinary skill in the art that, although welding is described as the method to secure the removable protective foil 330 to the cover layer 328, other methods familiar to those in the art may also be used including, but not limited to, heat sealing or adhesive, provided the protective foil 330 may easily be removed by a consumer.

(25) The top cover 332 is hollow and includes a plurality of air inlets 350 towards its distal end and an air outlet (not shown) at its proximal end. The air inlets 350 and the air outlet are connected by an air flow channel (not shown) which is defined between an internal wall surface (not shown) of the top cover 332 and the cover layer 328 below.

(26) During use, the protective foil 330 is removed by pulling the tab 348 in a longitudinal direction that and away from the cartridge 320. Once the protective foil 330 has been removed, the aerosol-forming substrates 324 are in fluid communication with the air flow channel via the permeable window 342 in the cover layer 328. The cartridge 320 is then inserted into an aerosol-generating device, as shown in FIGS. 1A and 1B, so that the electrical contacts 338 connect with the corresponding electrical contacts in the cavity of the device. Electrical power is then provided by the device to the heater 326 of the cartridge to release aerosol from one or more of the aerosol-forming substrates. When a user sucks or puffs on the mouthpiece portion of the device, air is drawn from the air inlets in the mouthpiece, into the air inlet 350 of the top cover and through the air flow channel in the top cover, where it is mixed with the aerosol. The air and aerosol mixture is then drawn through the air outlet of the cartridge 320 to the outlet of the mouthpiece portion.

(27) Once the aerosol-forming substrate 324 has been consumed by a user, the cartridge is removed from the cavity of the device and replaced.

(28) FIGS. 4A and 4B show a third embodiment of aerosol-forming cartridge 420. In this example, the cartridge 420 is substantially flat and has a rectangular cross-section, although it could be any other suitable flat shape. The cartridge comprises a base layer 422 formed from an intermediate layer 423 and a first heater 426 placed beneath and fixed to the intermediate layer 423. The cartridge also comprises an aerosol-forming substrate 424 arranged in the base layer 422 and a second heater 427 positioned over the aerosol-forming substrate 424 and fixed to the top of the base layer 422. The intermediate layer 422, the aerosol-forming substrate 424 and first and second heaters 426, 427 are all substantially flat and substantially parallel to each other. The contact surfaces between any two of these components 420 are substantially planar and substantially parallel with each other.

(29) The intermediate layer 423 has a cavity 434 extending through its thickness, the bottom of which is closed by the first heater 426. The aerosol-forming substrate 424 is held in the cavity 434. In this example, the cavity 434 is substantially rectangular and arranged with its long sides substantially parallel to the longitudinal axis of the cartridge 420. The aerosol-forming substrate 424 comprises a tobacco-containing material with volatile flavour compounds which are releasable upon heating by the first and second heaters 426, 427. In this example, the aerosol-forming substrate is a substantially flat rectangular block of tobacco cast leaf.

(30) The first and second heaters 426, 427 each comprise a plurality of heating elements 436 connected to electrical contacts 438. In this example, the heaters 426, 427 are each formed by disposing electrical contacts 438 and heating elements 436 on an electrically insulating substrate foil 437. Each electrically insulating substrate foil 437 is sized to extend across the width and length of each cavity 434. The first and second heaters 426 thus close off the top and bottom of the cavity 434 and help to keep the aerosol-forming substrate 424 within the cavity 434. The aerosol-forming substrate 424 can be held tightly within the cavity 434 by ensuring that the thickness of the base layer 422 is substantially the same as that of the aerosol-forming substrate.

(31) The electric contacts 438 extend along a side edge of the electrically insulating substrate foil 437. The electric contacts of the first heater are accessible from outside of the cartridge from underneath and the electric contacts of the second heater are accessible from outside of the cartridge from above. The electrically insulating substrate foil 437 of one or both of the first and second heaters 426, 427 is perforated to allow aerosol released by the aerosol-forming substrate 424 to pass through the first and second heaters 426, 427. Although the heaters 426, 427 are described as being perforated, one or both could instead include one or more gas permeable windows. It will be apparent that it is sufficient for only one of heaters 426, 427 to be permeable to aerosol.

(32) During use, the cartridge 420 is inserted into an aerosol-generating device, as shown in FIGS. 1A and 1B, so that the electrical contacts 438 connect with the corresponding electrical contacts in the cavity of the device. Electrical power is then provided by the device to the first and second heaters 426 to release aerosol from the aerosol-forming substrate. When a user sucks or puffs on the mouthpiece portion of the device, air is drawn from the air inlets in the mouthpiece, through the mouthpiece portion, where it is mixed with the aerosol. The air and aerosol mixture is then drawn through the outlet of the mouthpiece portion.

(33) Once the aerosol-forming substrate 424 has been consumed by a user, the cartridge is removed from the cavity of the device and replaced.

(34) FIGS. 5 and 6 show schematic illustrations of manufacturing processes for making the aerosol-forming cartridges of FIGS. 2A, 2B and 3A, 3B. In both of the processes described, the cartridges are assembled vertically at a number of different stations along an assembly line as a stream of cartridge components is conveyed along the assembly line. The term manufactured vertically, refers to the fact that the cartridge components are placed on each other in the vertical direction and in sequence to build the cartridge up as it travels along the conveyor, generally starting with the lowermost element and placing subsequent elements on top to end with the uppermost element of the cartridge. The contact surfaces between adjacent components are substantially planar and substantially parallel. With this approach, only vertical assembly operations are required. Thus, there is no need for any more complex assembly operations, such as rotational or multi-translational movements when forming the cartridges.

(35) FIG. 5 shows a schematic illustration of a manufacturing process for making the aerosol-forming cartridge 220 of FIGS. 2A and 2B using an assembly line 500 having a number of different stations.

(36) At a first station 510, individual, injection-moulded base layers 222 are fed, as indicated by the arrow, onto a conveyor 512 by a first automated placement device 514, such as a pick and place machine. The conveyor 512 is a continuous belt with a plurality of cavities (not shown) on its top surface for receiving the base layers and ensuring correct placement of the base layers on the conveyor 512. The cavities may be arranged in a grid and the first automated placement device 514 may be arranged to pick up and place a plurality of base layers in the cavities in one operation so that multiple cartridges can be produced simultaneously. The following description of the process refers to the manufacture of an individual cartridge, although it could apply to multiple cartridges.

(37) At a second station 520, a web of electric heater foil 522 is fed from a bobbin 524 to the conveyor 512 and an individual electric heater 226 is cut from the web of foil by a cutting device 526 and placed in the cavity 234 on the top surface of the base layer by a second automated placement device 528. During this step, the electric heater is placed so that its electrical contacts 238 are in line with the contact apertures 240 in the base layer. In this example, the web of electric heater foil comprises an electrically conductive foil, such as stainless steel, which is stamped by the cutting device 526 to form the electric heating elements 236 and electric contacts 238.

(38) At a third station 530, the aerosol-forming substrate 224 is fed to the conveyor 512 and placed in the cavity 234 on the top surface of the base layer 222 and on top of the electric heater 226 by a third automated placement device 532, such as a pick and place machine. In this example, the aerosol-forming substrate comprises a solid substrate. In examples where the aerosol-forming substrate comprises a liquid substrate absorbed in a porous carrier, the porous carrier is first placed in the cavity by the third automated placement device 532 and the liquid substrate is then dispensed onto the porous carrier using an automated vertical dosing and filling apparatus (not shown).

(39) At a fourth station 540, an injection-moulded cover layer 228 is fed to the conveyor 512 and placed over the base layer 222, the aerosol-forming substrate 224 and the electric heater 226 by a fourth automated placement device 542. Preferably, the cover layer is placed on the base layer so that at least part of its gas permeable window 242 is above at least part of the electric heater to improve a flow of aerosol through the gas permeable window during use of the cartridge.

(40) At a fifth station 550, the cover layer 228 is welded to the base layer 222 using a first automated ultrasonic welding device 552.

(41) At a sixth station 560, a web of protective foil 562 is fed from a bobbin 564 to the conveyor 512 and an individual protective foil 230 is cut from the web of protective foil. The protective foil is applied over the cover layer 228 so that the tab 248 extends in the opposite direction to that of the assembled cartridge, that is, in the direction of the end of the cartridge 220 at which the electrical contacts 640 are located. The protective foil is removably attached to the cover layer by ultrasonic welding to form a continuous sealing line around the gas permeable window 242 of the cover layer and the protective foil is then folded back on itself along a transverse fold line 249 so that the tab extends beyond the cover layer in the direction shown in FIG. 2A. The cutting, welding and folding steps can be carried out by a single machine 566 or by two or more separate devices.

(42) At a seventh station 570, an injection-moulded top cover 232 is fed, as indicated by the arrow, to the conveyor 512 by a seventh automated placement device 572, such as a pick and place machine.

(43) At an eighth station 580, the top cover 232 is welded to the cover layer 228 by a second automated ultrasonic welding device 582 to complete the assembly of the cartridge.

(44) The completed cartridge is then conveyed to a packer 590, where it is combined with other completed cartridges and packaged for sale.

(45) FIG. 6 shows a schematic illustration of a manufacturing process for making the aerosol-forming cartridge 320 of FIGS. 3A and 3B using an assembly line 600 having a number of different stations. Ata first station 610, a web of electric heater foil 612 is fed from a bobbin 614 to the assembly line. The web of electric heater foil 612 comprises an electrically insulating substrate on which a plurality of electric heating elements and electrical contacts are disposed so that the web of electric heater foil 612 may be cut to form individual electric heaters for individual cartridges. The web of electric heater foil 612 may have a width that is several multiples of that of each completed cartridge so that multiple cartridges can be manufactured simultaneously.

(46) At a second station 620, a web of intermediate layer foil 622 is fed from a bobbin 624 to the assembly line and over the electric heater foil 612. The web of intermediate layer foil 622 and the electric heater foil 612 are laminated together by a first laminating device 626 to form a web of base layer foil 628. In this example, the web of intermediate layer foil 622 and the web of electric heater foil 612 are pressed together and heated in the first laminating device 626 so that the two webs fuse together, although any other suitable laminating process may be used. In this example, the web of intermediate layer foil 622 is pre-cut with a plurality of apertures for forming the cavities 334 in each intermediate layer 323 before winding on the bobbin 624, although the apertures could be cut after unwinding form the bobbin 624 by a cutting device (not shown) positioned between the bobbin 624 and the first laminating device 626.

(47) At a third station 630, the aerosol-forming substrates 324 are fed to the base layer foil 628 and placed in the cavities 334 in the base layer foil 628 by a first automated placement device 632, such as a pick and place machine. In alternative embodiments in which the aerosol-forming substrate comprise a slurry, a thin shield layer, which also has a plurality of apertures corresponding to the apertures in the intermediate layer foil 622, may be removably attached to the upper surface of the web of intermediate layer foil 622, for example using adhesive. After the slurries are dispensed into the cavities 334 by the first automated placement device, which in this case may be an automated vertical dosing and filling apparatus (not shown), the shield layer is removed from the intermediate layer foil 622 to reveal a clean upper surface for subsequent process steps. In alternative embodiments in which the aerosol-forming substrates comprise a liquid substrate absorbed in a porous carrier, the porous carrier is first placed in the cavity by the first automated placement device 632 and the liquid substrate is then applied to the porous carrier using an automated vertical dosing and filling apparatus (not shown) positioned after the first automated placement device 632.

(48) At a fourth station 640, a web of cover layer foil 642 is fed from a bobbin 644 to the assembly line and over the base layer foil 628. The web of cover layer foil 642 and the web of base layer foil 628 are laminated together by a second laminating device 646. In this example, the web of base layer foil 628 and the web of cover layer foil 642 are pressed together and heated in the second laminating device 646 so that the two webs fuse together, although any other suitable laminating process may be used. The web of cover layer foil 642 comprises a polymeric foil with a plurality of pre-formed grids for forming the gas permeable window 342 in the cover layer 328 of each cartridge 320.

(49) At a fifth station 650, a web of protective foil 652 is fed from a bobbin 654 to the assembly line and over the web of cover layer foil 642. The web of protective foil 652 is pre-cut so that individual protective foils 330 can be separated from the web of protective foil 652. Individual protective foils 330 are applied over the web of cover layer foil 642 so that their respective tabs 348 extend in the opposite direction to that of the assembled cartridge, that is, in the direction of the upstream end of the cartridge 320 at which the air inlets 350 will be located. Each protective foil 330 is removably attached to the cover layer foil 642 by ultrasonic welding to form a continuous sealing line around a gas permeable window 342 in the cover layer foil 642 and is folded back on itself along a transverse fold line 349 so that the tab 348 extends in the upstream direction, that is, in the direction in which it extends in FIG. 3A. The cutting, welding and folding steps can be carried out by a single machine 656 or by two or more separate devices.

(50) At a sixth station 660, an injection-moulded top cover 332 is fed to the assembly line and over the protective foil 330 by a second automated placement device 662, such as a pick and place machine.

(51) At a seventh station 670, the top cover 332 is welded to the cover layer 328 by an automated ultrasonic welding device 672 to complete the assembly of the cartridge.

(52) The completed cartridge is then conveyed to a packer 690, where it is combined with other completed cartridges and packaged for sale.

(53) In each of the above described processes, any two or more of the foil webs may be indexed to ensure precise relative positioning of the various components of each cartridge. For example, the foil webs may have perforated edges by which they are indexed.

(54) The exemplary embodiments described above illustrate but are not limiting. In view of the above discussed exemplary embodiments, other embodiments consistent with the above exemplary embodiments will now be apparent to one of ordinary skill in the art.