Apparatus arranged to heat smokable material and method of forming heater

Abstract

To provide an apparatus arranged to heat smokable material to volatilize at least one component of the smokable material.SOLUTION: An apparatus 10 includes: a housing 14 for receiving smokable material; and at least one heater 20 arranged within the housing 14, for heating the smokable material removably received within the housing 14 during use. The heater 20 has first and second ends and a hollow central portion in which the smokable material is received during use, and the heater is formed from a sheet which is rolled into a tube and sealed along its length to prevent air from entering or leaving the heater except through at least one of the first and second ends.SELECTED DRAWING: Figure 3

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is related to U.S. Provisional Patent Application No. 62 / 185,227, filed June 26, 2015, the entire contents of which are incorporated herein by reference. [Technical field]

[0002] The present invention relates to a device configured to heat smokable material and a method of forming a heater for a device configured to heat smokable material. [Background technology]

[0003] During use, articles such as cigarettes and cigars burn tobacco to produce tobacco smoke. Attempts have been made to provide an alternative to these articles that burn tobacco by creating products that release compounds without burning. Examples of such products are the so-called heat-not-burn products, also known as tobacco heating products or tobacco heating devices. These release compounds by heating, rather than burning, a material. The material may be, for example, tobacco or other non-tobacco products or combinations such as blended mixtures, which may or may not contain nicotine. Similarly, there are so-called electronic cigarette devices, which typically vaporize a liquid, which may or may not contain nicotine. Summary of the Invention

[0004] According to a first aspect of the present invention there is provided an apparatus configured to heat a smokable material to volatilise at least one component of the smokable material, the apparatus comprising: a housing for receiving smoking material; at least one heater disposed within the housing for heating, in use, smokable material removably received within the housing; Equipped with The heater has a first end, a second end and a hollow central portion for receiving smokable material in use, the heater being formed from a sheet rolled into a tube and the sheet sealed along its length to prevent air from entering or leaving the heater other than through at least one of the first and second ends.

[0005] In some instances, this prevents air from entering the hollow central portion of the heater in other parts of the device, e.g., to prevent contamination of the air (including components volatilized from the smokable material during use) flowing through the air flow path defined by the hollow central portion of the heater. Conversely, this also helps to prevent airflow leaking through the hollow central portion of the heater into other parts of the device.

[0006] In one exemplary embodiment, the sheet includes a layer of plastic. In one exemplary embodiment, the layer is a polyimide layer. Furthermore, in one exemplary embodiment, the device includes at least one conductive path disposed on the layer, the conductive path providing a heating element of the heater.

[0007] In one exemplary embodiment, the device includes a further layer of plastic disposed over the conductive tracks such that the conductive tracks are between the layer of plastic and the further layer of plastic. In a particular example, the generally flat sheet material that is rolled to form the heater is a multi-layer sheet made by laminating multiple layers of polyimide and conductive tracks on top of each other.

[0008] In one exemplary embodiment, the heater is a thin film heater, and in one exemplary embodiment, the device includes thermal insulation surrounding the heater to reduce heat loss from the heater to the exterior of the device.

[0009] According to a second aspect of the present invention there is provided a method for forming a heater for a device configured to heat smokable material to volatilize at least one component of the smokable material, the method comprising: rolling the sheet into a hollow tube having a first end and a second end; sealing the tube along its length such that, in use, air does not enter or leave the heater except through at least one of said first end and said second end; Includes.

[0010] In one exemplary embodiment, the sheet includes a layer of plastic. Also, in one exemplary embodiment, the layer is a polyimide layer. In one exemplary embodiment, the method includes forming at least one conductive path on the layer prior to rolling the sheet into a hollow tube. Furthermore, in one exemplary embodiment, the method includes forming a further layer of plastic on the conductive path such that the conductive path is between the layer of plastic and the further layer of plastic.

[0011] In an exemplary embodiment, the heater is a thin film heater.

[0012] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a first perspective view of an example apparatus for heating smokable material. [Diagram 2] FIG. 2 is a second perspective view of the device of FIG. 1. [Diagram 3] FIG. 2 is a cross-sectional view of the device of FIG. 1 with smokable material inserted; [Figure 4] 2 is a cross-sectional view of the device of FIG. 1 without any smokable material inserted therein; [Diagram 5] FIG. 5 is a detailed view of the area marked 5 in FIG. 4. [Figure 6] FIG. 5 is a detailed view of the area marked 6 in FIG. 4. [Figure 7] FIG. 5 is a detailed view of the area marked with the numeral 7 in FIG. 4. [Figure 8]FIG. 2 is a longitudinal sectional view of the device of FIG. [Figure 9] FIG. 5 is a detailed view of the area marked 9 in FIG. 4. [Figure 10] FIG. 5 is a detailed view of the area designated by reference numeral 10 in FIG. 4.

[0014] As used herein, the term "smoking material" includes materials that, when heated, provide volatile components, typically in the form of an aerosol. "Smoking material" includes any tobacco-containing material, and may include, for example, one or more of tobacco itself, tobacco derivatives, expanded tobacco, reconstituted tobacco, or tobacco substitutes. "Smoking material" may also include other non-tobacco products, which may or may not contain nicotine, depending on the product. "Smoking material" may take any form, such as, for example, a solid, liquid, gel, or wax. "Smoking material" may also be, for example, a combination or blend of materials.

[0015] Typically, devices are known that heat smoking material to volatilize at least one component of the smoking material to form an aerosol that can be inhaled without burning or combusting the smoking material. Such devices are also described as "non-combustion heating" devices, or "tobacco heating products", or "tobacco heating devices", or the like. There are also so-called e-cigarette devices, which typically vaporize smoking material in liquid form, which may or may not contain nicotine. The smoking material may take the form of, or be provided as part of, a rod, cartridge, cassette, or the like that can be inserted into the device. A heater for heating and volatilizing the smoking material may be provided as a "permanent" part of the device, or may be provided as part of a smoking article, or as a consumable item that is discarded and replaced after use. In this context, a "smoking article" is a device, article, or other component that contains or contains smoking material during use, and that is heated during use to volatilize the smoking material and optionally other components.

[0016] 1-4, an example of a device 10 is shown that is configured to heat smokable material to volatilize at least one component of the smokable material, typically to form an inhalable aerosol. FIG. 3 shows the device 10 with smokable material inserted, and FIG. 4 shows the device 10 without smokable material inserted. The device 10 is a heating device that releases compounds by heating smokable material without burning it. The first end 11 is also referred to herein as the mouth end or proximal end 11, and the second end 12 is also referred to herein as the distal end 12. The device 10 is provided with an on / off button (not shown) that allows the entire device 10 to be turned on and off as desired by the user.

[0017] The device 10 has a housing for positioning and protecting the various internal components of the device 10. In the illustrated example, the device 10 is formed from one or more internal "chassis" portions and one or more external sleeve portions. In the particular example shown, the device 10 has a single external sleeve or housing 14 and an internal chassis 16. In a particular example, the internal chassis 16 may be formed from two chassis halves and, optionally, other chassis portions. During assembly of the device 10, the various internal components of the device 10 are positioned and / or secured within the chassis 16, and then the internal components and the chassis, or chassis portion 16, are slid within the housing 14. The chassis or chassis portion 16 may be removably attached to the housing 14 to allow easy access to the interior of the device 10, or may be "permanently" secured to the chassis 16, for example, to prevent a user from accessing the interior of the device 10. In the particular example shown, chassis 16 provides or supports at least partially the front wall of device 10 at first or oral end 11 and at least partially the rear wall of the device at second or distal end 12. In one example, chassis 16 is made of a plastic material including, for example, glass-filled nylon formed by injection molding, although other materials and manufacturing processes may be used.

[0018] The housing 14 has disposed therein or secured thereto the heater 20, the control circuitry 21 and the power source 22. In this example, the heater 20, the control circuitry 21 and the power source 22 are laterally adjacent (i.e., side-by-side when viewed from one end) with the control circuitry 21 generally disposed between the heater 20 and the power source 22, although other locations are possible. The control circuitry 21 may include a controller, such as a microprocessor device, constructed and arranged to control the heating of the smokable material, as described further below. The power source 22 may be a battery, such as, for example, a rechargeable battery or a non-rechargeable battery. Examples of suitable batteries include, for example, lithium ion batteries, nickel batteries (such as nickel-cadmium batteries), alkaline batteries, and the like. The battery 22 is electrically connected to the heater 20 to provide power when required and to heat the smokable material under the control of the control circuitry 21 (to volatilize the smokable material without burning it, as previously described). An advantage of locating the power supply 22 to the side of the heater 20 is that a physically larger power supply 22 can be used without making the overall device 20 unduly long. As will be appreciated, a physically larger power supply 22 generally has a higher capacity (i.e., total electrical energy that can be supplied, often measured in ampere-hours or the like) and therefore may provide longer battery life for the device 10.

[0019] In one example, the heater 20 takes the form of a generally cylindrical hollow tube having a hollow internal heating chamber 23 into which the smokable material is inserted for heating during use. The heater 20 may have other different configurations. For example, the heater 20 may be formed as a single heater or may be formed from multiple heaters aligned along the longitudinal axis of the heater 20. (For simplicity, the term "heater" in this document shall be construed to include multiple heaters unless the context otherwise requires.) The heater 20 may be annular, tubular, or may have at least a partial annular or partial tubular shape therearound. In one example, the heater 20 may be a thin film type heater. In one particular example, the heater 20 is supported by a stainless steel support tube. The heater 20 is dimensioned such that substantially the entire smokable material is disposed within the heating element of the heater 20 upon insertion, and substantially the entire smokable material is heated during use. The heater 20 may be arranged so that selected zones of smokable material are heated individually, for example in sequence (gradually) or together (simultaneously) as required.

[0020] The heater 20 in this example is surrounded along at least a portion of its length by a thermal insulator 24. The thermal insulator 24 helps to reduce heat transfer from the heater 20 to the exterior of the device 10. This generally reduces heat loss and therefore helps to keep the power requirements of the heater 20 low. The thermal insulator 24 also helps to keep the exterior of the device 10 cool during operation of the heater 20. In one example, the thermal insulator 24 may be a double-walled sleeve having a low pressure area between the two walls of the sleeve. That is, the thermal insulator 24 may be, for example, a "vacuum" tube, i.e., a tube that is at least partially evacuated to minimize heat transfer by conduction and / or convection. Other configurations for the thermal insulator 24 are possible in addition to or instead of a double-walled sleeve, such as using insulating materials, including, for example, suitable foam-type materials.

[0021] The front of the chassis 16 has an opening 30 at the mouth end 11 through which a user inserts and removes smoking material into and from the device 10 during use. A lid 31 is provided at the mouth end 11. The lid 31 is opened during use to allow smoking material to be inserted and removed from the device 10 through the opening 30, while the opening 30 is closed during non-use to keep the inside of the device 10 clean and to prevent damage to the inside of the device 10. The lid 31 in this example is a sliding lid that can slide up and down to open and close the opening 30. In other examples, the lid 31 may be a hinged lid, or other configurations may be provided. The lid 31 in this example is provided in association with the front component 32.

[0022] The front component 32 has at least one part. In the particular example shown, the front component 32 has three parts: a front part 32a, a middle part 32b, and a rear part 32c. For example, the middle part 32b may be secured to the rear part 32c with an adhesive, such as a double-sided sticky tape.

[0023] The front lid 31 of the device 10 is constructed and arranged to be slidably connected to the front component 32. The front lid 31 may be slidably attached to the front component 32 by a protrusion and recess combination. The front lid 31 in the illustrated example has a rearwardly facing protrusion 31' that is received within a recess or channel 32' in the front component 32. The front lid 31 is secured in place using screws 32" but allows the front lid 31 to slide up and down within the channel 32'.

[0024] 3, there is shown a rod 50 having (at least) smokable material 51 partially inserted through the opening 30 such that the smokable material 51 is disposed within the heating chamber 23 of the heater 20 and is heated when the heater 20 is activated. In this example, the rod 50 has a mouthpiece assembly at its oral end, the mouthpiece assembly including one or both of a filter for filtering the aerosol and / or a cooling element 52 for cooling the aerosol. The filter / cooling element 52 is spaced from the smokable material by a spacer 53 and is spaced from the oral end of the rod 50 by another spacer 54.

[0025] The rear wall 18 of the housing 14 has an opening 35 at the distal end 12 of the device 10. A lid 36 is provided at the distal end 12. The lid 36 can be opened to allow access to the opening 35 at the distal end 12 and closed to close the opening 35 at the distal end 12. The door 36 at the distal end 12 in this example is a hinged lid. In other examples, the lid 36 can be a sliding lid or other configurations can be provided. When the lid 36 at the distal end 12 is a hinged lid, the hinge can be provided as a "living hinge". More preferably, the lid 36 is a separate component and the hinge of the lid 36 is a barrel hinge.

[0026] In the assembled device 10, the heater 20 is in the form of a cylindrical hollow tube and is positioned within the chassis 16 such that one end of the hollow tube is in fluid communication with the opening 30 at the oral end 11 and the other end is in fluid communication with the opening 35 at the distal end.

[0027] In use, the user closes the lid 36 at the distal end 12 to close the opening 35 at the distal end 12, and opens the lid 30 at the mouth end 11 to open the opening 30 at the mouth end 11. The user then inserts a rod 50 containing smokable material 51 into the heating chamber 23 of the heater 20 through the opening 30 at the mouth end 11, activates the device 10 to heat the smokable material 51 to generate the desired inhalable aerosol, and then removes the rod 50 with the used smokable material 51 from the device 10 through the opening 30 at the mouth end 11. The user can open the lid 36 at the distal end 12 to open the opening 35 at the distal end 12 after the device 10 has been used. The opening 35 at the distal end 12 allows the user to access the interior of the device 10, particularly the area of ​​the opening 35 at the distal end 12. This allows the user to clean the interior of the device 10 in the area of ​​the opening 35 at the distal end 12 as desired, when necessary. This access at the distal end 12, among other things, allows the user to clean the heater 20 and the interior of the heating chamber 23 at the distal end 12. In fact, because the heater 20 is disposed between the opening 30 at the oral end 11 and the opening 35 at the distal end 12, and the hollow heater 20 effectively forms a straight through hole through the entire device 10 between the opening 30 at the oral end and the opening 35 at the distal end, the user can easily clean substantially the entire hollow heating chamber 23 as well. To this end, the user can selectively access the heating chamber 23 through the openings 30, 35. For this purpose, the user can use one or more of a variety of cleaning tools, including, for example, a traditional pipe cleaner or a brush.

[0028] In one example, the heating chamber 23 has a region of reduced inner diameter towards the distal end 12. This provides an end stop for the smokable material passing through the first opening 30 at the mouth end 11 to prevent the smokable material from passing straight through the second opening 35 at the distal end 12. In the example shown, this region of reduced inner diameter is provided by a hollow tube 40 disposed within the end of the heating chamber 23 towards the distal end 12. The hollow tube 40 in this example has an outwardly extending head or flange 41. The hollow tube 40 may be formed of a plastic material including, for example, polyetheretherketone (PEEK). The hollow tube 40 may be secured in place by, for example, an adhesive or a twist lock mechanism.

[0029] During manufacture of the device 10, the hollow tube 40 is inserted from the outside into the opening 35 at the distal end 12, with the head or flange 41 providing a stop against the chassis 16 to position the hollow tube 40 in place. The heater 20 is then positioned within the chassis 16 and the hollow tube 40 is inserted into the distal end of the interior chamber 23 of the heater 20. Thus, in this case, the hollow tube 40 provides an area of ​​reduced inner diameter within the heating chamber 23 that acts as a stop for smokable material inserted within the interior chamber 23 of the heater 20, which also supports and positions the heater 20 within the device 10 at the distal end 12. To further explain the support and positioning of the heater 20 within the device 10, a tubular mouthpiece component 33 is provided at the mouth end 11 to support and position the front end of the heater 20.

[0030] It has been found that an important requirement of the apparatus 10 is that the airflow through the internal chamber 23 of the heater 20 be isolated, or at least substantially isolated, from the remainder of the apparatus 10. This is to prevent or minimize contamination of the airflow through the internal chamber 23 of the heater 20 with air that has passed through the control circuitry 21 and / or power source 22, etc. Similarly, this is to prevent or minimize airflow through the internal chamber 23 of the heater 20 passing through or alongside the control circuitry 21 and / or power source 22, etc.

[0031] 3 and 4, a heater 20 in an apparatus for heating smokable material, including for example the apparatus 10 as described above, is formed from a sheet, i.e. a generally flat sheet material, which is rolled and sealed along the length of the tube. The rolled heater 20 may have a tubular shape with a first end, a second end and a hollow central portion. The hollow central portion may receive smokable material in use. The smokable material is inserted into the hollow central portion through one of the first and second ends. The tube is sealed along its entire length to prevent air from entering or leaving the heater except through one or more of the first and second ends. The tube may be sealed, for example, using an adhesive, particularly a pressure sensitive adhesive. In a specific embodiment, the heater 20 is a thin film heater.

[0032] The tubular heater 20 may be made from a substrate having at least one conductive track formed thereon. The substrate may be in the form of a sheet and may, for example, include a layer of plastic. In a particular example, this layer is a polyimide layer. The conductive track is printed or otherwise deposited onto the layer. The tubular heater 20 may have a further plastic layer formed on or over the conductive track. In this example, the conductive track is between two plastic layers.

[0033] 3 and 4, the tubular heater 20 is disposed within a first compartment 38, which may be referred to as the heating compartment of the device 10. The device 10 may also have a second compartment 60, which may be referred to as the electronics compartment 60, which includes at least one of the control circuitry 21 and the power source 22. In the example shown in FIGS. 3 and 4, the electronics compartment 60 includes both the control circuitry 21 and the power source 22. The first heating compartment 38 is spaced apart from the second electronics compartment 60 such that the two compartments 38, 60 are substantially hermetically sealed from each other to minimize or prevent air or vapor from passing between the compartments 38, 60. The hermetic sealing or separation of the compartments 38, 60 may allow only a negligible amount of air to flow between the compartments 38, 60. In a particular example, the isolation of the compartments 38, 60 is such that the amount of air or steam passing between the compartments 38, 60 is less than about 1% of the total airflow through the heating chamber 23, and ideally none at all. (It will be seen that there is a passageway 62 between the compartments 38, 60 through which passes a heater end 64 which connects the heater 20 to the control circuitry 21 and power source 22 in the electronics compartment 60, as will be described in more detail below.)

[0034] 3 and 4, the device 10 of this example has a partition wall 66 between the first heating compartment 38 and the second electronics compartment 60. The partition wall 66 may be a separate component or may be integrally formed with the chassis or chassis portion 16. In the illustrated example, the partition wall 66 is disposed between the front of the device 10 and the rear wall 18 of the device 10. The partition wall 66 may partially form one or both of the first heating compartment 38 and the second electronics compartment 60. The partition wall 66 may be made of a thermoplastic resin such as acrylonitrile butadiene styrene (ABS) since it may be subjected to indirect heating from the heater 20 and must be able to withstand the heat. The partition wall 66 may be overmolded with a sealing material such as thermoplastic polyurethane (TPU) to close the air path from the electronics outside the chassis 16.

[0035] The leading edge of the partition 66 in the illustrated example is received in a recess 67 in the chassis 16 in a "tongue and groove" configuration to facilitate construction and assembly of the device 10. The trailing edge of the partition 66 in the illustrated example is received in a seal 68, again in this example in a tongue and groove configuration. The seal 68 that receives the partition 66 is a resilient member. The seal 68 may be made of one or more polymers, such as silicone or rubber, and may be in the form of a grommet or cap, which may be, for example, injection molded. In other examples not illustrated, the leading edge of the partition 66 may be received in a seal similar to the seal 68 for the trailing edge.

[0036] 5-7, there are shown detailed views of certain areas of the device 10 shown in FIG. 4. Each of FIGS. 5-7 shows at least one seal within the device 10 that helps provide a substantially airtight seal between the heating compartment 38 and the electronics compartment 60. It will be understood that certain examples show multiple seals, and that not all of these seals may be present in an embodiment; that is, some embodiments may have one of the seals described herein, or two or more of the seals described herein, or all of the seals described herein.

[0037] 5 shows a seal 72 between the housing 14 and the front piece 32a of the front component 32 of the device 10. The seal 72 is seated in a groove or recess 80 in one or both of the front piece 32' of the front component 32 and the housing 14. The seal 72 may be compressed to ensure a tight bond between the housing 14 and the front component 32. The seal 72 is a resilient member. The seal 72 may be made of one or more polymers, including, for example, silicone or rubber. The seal 72 may be overmolded with a sealing material, such as, for example, thermoplastic polyurethane.

[0038] 6 shows a seal 74 between the housing 14 and rear wall 18 of the device 10. The seal 74 seats in a groove or recess 82 in one or both of the rear wall 18 and the housing 14. The seal 74 can be compressed to ensure a tight bond between the housing 14 and rear wall 18. The seal 74 is a resilient member. The seal 74 can be made of one or more polymers, including, for example, silicone or rubber. The seal 74 may be overmolded with a sealing material, such as, for example, thermoplastic polyurethane.

[0039] FIG. 7 shows a seal 68 that receives the second end of the partition wall 66. FIG. 7 also shows a seal 70 disposed opposite the seal 68 that receives the second end of the partition wall 66. The two seals 68, 70 shown are disposed between the first compartment 38 and the second compartment 60. The seals 68, 70 are disposed to be pressed against each other such that the seal between the seals 68, 70 is substantially airtight. The seal 70 in this example is an elastic member. The seal 70 may be made of one or more polymers such as, for example, silicone or rubber.

[0040] As mentioned above, in the illustrated embodiment, a passageway 62 is provided between the compartments 38, 60 through which an end 64 of the heater 20 can pass to connect the heater 20 to at least the power source 22. In the illustrated embodiment, the heater end 64 connects the heater 20 to the control circuitry 21 and power source 22 in the electronics compartment 60.

[0041] 7 is an enlarged view of the area around the passageway 62 between the compartments 38, 60. A heater end 64 occupies the passageway 62. The heater end 64 is disposed between a seal 68 that receives a second end of the partition wall 66 and a seal 70 that is disposed opposite the seal 68 that receives the second end of the partition wall 66. The seals 68, 70 are compressed against the heater end 64 to maintain a substantially airtight seal between the compartments 38, 60.

[0042] Figure 8 shows a longitudinal cross-sectional view of the device 10. Figures 9 and 10 show detailed views of two areas of the device 10 shown in Figure 8.

[0043] 8-10, there is shown a partition wall 66 disposed between the chassis 16 of the device 10. The partition wall 66 along a first edge is received in a tongue and groove configuration within a recess 16' in the chassis 16 of the device 10. The first edge of the partition wall 66 may be secured within the recess 16' of the chassis 16 by, for example, an adhesive or by a simple press or friction fit.

[0044] The illustrated partition 66 has a groove 84 along a second edge of the partition 66. The seal 76 is disposed within the groove 84 of the partition 66. The seal 76 abuts against the chassis 16 of the device 10. The seal 76 and groove 84 are arranged such that a substantially airtight seal is formed along the second edge of the partition 66. The seal 76 is a resilient member. The seal 76 may be made of one or more polymers, such as, for example, silicone or rubber. The seal 76 may be overmolded with a sealing material, such as, for example, thermoplastic polyurethane, within the groove 84.

[0045] Referring now specifically to Figure 9, there is shown a detailed view of the area of ​​device 10 shown in Figure 8. An additional seal 78 is provided between the housing and side plate of the device to provide an external seal between the air passages and the electronics. The additional seal 78 is overmolded with a sealing material, such as thermoplastic polyurethane, which is disposed in groove 86 and compressed between the housing 14 and chassis 16.

[0046] The various embodiments described herein are presented only to aid in the understanding and teaching of the claimed features. These embodiments are provided merely as representative examples of embodiments and are not intended to be comprehensive and / or exclusive. The advantages, embodiments, examples, functions, features, structures, and / or other aspects described herein should not be considered as limiting the scope of the invention as defined by the claims or the equivalents of the claims, and it is understood that other embodiments may be utilized and modifications may be made without departing from the scope of the claimed invention. The various embodiments of the present invention may suitably comprise, consist of, or consist essentially of any suitable combination of the disclosed elements, components, features, parts, steps, means, etc., other than those specifically described herein. Furthermore, the present disclosure may include other inventions not currently described in the claims but which may be described in the future.

Claims

1. 1. An apparatus configured to heat a smokable material to volatilize at least one component of the smokable material, comprising: a housing for receiving smoking material; at least one heater disposed within said housing for heating smokable material removably received within said housing in use; Equipped with 1. An apparatus wherein the heater has a first end, a second end and a hollow central portion for receiving smokable material in use, the heater being formed from a sheet rolled into a tube and the sheet sealed along its length to prevent air from entering or leaving the heater other than through at least one of the first and second ends.

2. The apparatus of claim 1 , wherein the sheet comprises a layer of plastic.

3. The device of claim 2 , wherein the layer is a polyimide layer.

4. 4. Apparatus according to claim 2 or 3, comprising at least one conductive track provided on said layer, said conductive track constituting a heating element of said heater.

5. 5. The apparatus of claim 4, further comprising a further layer of plastic disposed over the conductive path, such that the conductive path is between the layer of plastic and the further layer of plastic.

6. The apparatus of any one of claims 1 to 5, wherein the heater is a thin film heater.

7. An apparatus according to any preceding claim, comprising a thermal insulator surrounding the heater to reduce heat loss from the heater to the exterior of the apparatus.

8. 1. A method for forming a heater for a device configured to heat smokable material to volatilize at least one component of the smokable material, comprising: rolling the sheet into a hollow tube having a first end and a second end; sealing the tube along a length of the tube such that, in use, air does not enter or leave the heater except through at least one of the first end and the second end; A method comprising:

9. The method of claim 8 , wherein the sheet comprises a layer of plastic.

10. The method of claim 9 , wherein the layer is a polyimide layer.

11. 11. The method of claim 9 or 10, comprising forming at least one conductive path on the layer prior to rolling the sheet into the hollow tube.

12. 12. The method of claim 11, comprising forming a further layer of plastic over the conductive path such that the conductive path is between the layer of plastic and the further layer of plastic.

13. The method according to any one of claims 8 to 12, wherein the heater is a thin film heater.

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