AEROSOL-GENERATING DEVICE AND AEROSOL-GENERATING SYSTEM COMPRISING A BIMETALLIC ELEMENT

Abstract

An aerosol-generating device is provided, including a housing including a first tubular section to receive a combustible heat source and a second tubular section to receive an aerosol-generating substrate; a heat-conductive element between the sections to transfer heat received in the first section to the substrate received in the second section, the element including a bimetallic element having first and second portions; and a heat-insulative sleeve around at least a portion of the second section including one or more air inlets, the bimetallic element arranged to deform from a first position where a first portion of the bimetallic element is proximate the first section and a second portion of the bimetallic element is proximate the second section, to a second position where the first portion of the bimetallic element is displaced away from the first section towards the second section, when the bimetallic element is heated above a threshold temperature.

Claims

1.-15. (canceled)

16. An aerosol-generating device, comprising: a housing comprising a first tubular section configured to receive a combustible heat source and a second tubular section configured to receive an aerosol-generating substrate; a heat-conductive element disposed between the first tubular section and the second tubular section of the housing configured to transfer heat from a combustible heat source received in the first tubular section to an aerosol-generating substrate received in the second tubular section, the heat-conductive element comprising a bimetallic element having a first portion and a second portion; and a heat-insulative sleeve around at least a portion of the second tubular section of the housing, wherein the heat-insulative sleeve comprises one or more air inlets, and wherein the bimetallic element is arranged to deform from a first position, in which the first portion of the bimetallic element is proximate the first tubular section of the housing and the second portion of the bimetallic element is proximate the second tubular section of the housing, to a second position, in which the first portion of the bimetallic element is displaced away from the first tubular section of the housing towards the second tubular section of the housing, when the bimetallic element is heated above a threshold temperature.

17. The aerosol-generating device according to claim 16, wherein the bimetallic element is pre-stressed such that the bimetallic element deforms from the first position to the second position with a snap action.

18. The aerosol-generating device according to claim 16, wherein the bimetallic element bends from the first position to the second position when heated above the threshold temperature.

19. The aerosol-generating device according to claim 18, wherein the bimetallic element is flat or convex relative to the first tubular section in the first position and concave relative to the first tubular section in the second position.

20. The aerosol-generating device according to claim 16, wherein the heat-conductive element further comprises a first elongate heat-conductive member that projects into the first tubular section of the housing and is configured for insertion into a combustible heat source received in the first tubular section.

21. The aerosol-generating device according to claim 16, wherein the heat-conductive element further comprises a second elongate heat-conductive member that projects into the second tubular section of the housing and is configured for insertion into an aerosol-generating substrate received in the second tubular section.

22. The aerosol-generating device according to claim 16, wherein the bimetallic element contracts from the first position to the second position when heated above the threshold temperature.

23. The aerosol-generating device according to claim 22, wherein the bimetallic element is a bimetallic helical coil or a bimetallic spiral coil.

24. The aerosol-generating device according to claim 16, wherein the housing is configured such that airflow from the first tubular section to the second tubular section of the housing is substantially prevented.

25. The aerosol-generating device according to claim 16, wherein one or more air inlets are provided in the second tubular section.

26. The aerosol-generating device according to claim 16, wherein one or both of the first tubular section and the second tubular section of the housing comprise thermally-conductive material.

27. The aerosol-generating device according to claim 16, further comprising: a heat-insulative cover around at least a portion of the first tubular section of the housing, wherein the heat-insulative cover is removably connected to the heat-insulative sleeve.

28. An aerosol-generating system, comprising: an aerosol-generating device according to claim 16; and one or more combustible heat sources configured to be inserted into the first tubular section of the aerosol-generating device.

Description

[0186] The invention will be further described, by way of example only, with reference to the accompanying drawings in which:

[0187] FIGS. 1a and 1b show an aerosol-generating device according to a first embodiment of the invention at a temperature below the threshold temperature;

[0188] FIG. 1c shows the aerosol-generating device according to the first embodiment of the invention shown in FIG. 1b at a temperature above the threshold temperature;

[0189] FIG. 2a shows an aerosol-generating device according to a second embodiment of the invention at a temperature below the threshold temperature;

[0190] FIG. 2b shows the aerosol-generating device according to the second embodiment of the invention at a temperature above the threshold temperature;

[0191] FIG. 3a shows an aerosol-generating device according to a third embodiment of the invention at a temperature below the threshold temperature; and

[0192] FIG. 3b shows the aerosol-generating device according to the third embodiment of the invention at a temperature above the threshold temperature;

[0193] The aerosol-generating device 2 according to the first embodiment of the invention shown in FIGS. 1a to 1c comprises a housing 4 comprising a first rigid cylindrical tubular section 6 and a second rigid cylindrical tubular section 8. The first tubular section 6 and the second tubular section 8 of the housing 4 are formed of thermally-conductive material. The aerosol-generating device 2 comprises a heat-conductive element 10 disposed between the first tubular section 6 and the second tubular section 8 of the housing 4.

[0194] The heat-conductive element 10 comprises a first heat-conductive component proximate the first tubular section 6 of the housing 4. The first heat-conductive component comprises a first heat-conductive disk 12 and a first elongate heat-conductive member 14 that projects from the first heat-conductive disk 12 into the first tubular section 6 of the housing 4.

[0195] The heat-conductive element 10 also comprises a second heat-conductive component proximate the second tubular section 8 of the housing 4. The second heat-conductive component comprises a second heat-conductive disk 16 and a second elongate heat-conductive member 18 that projects from the second heat-conductive disk 16 into the second tubular section 8 of the housing 4.

[0196] The heat-conductive element 10 further comprises a bimetallic element in the form of a bimetallic strip 20 disposed between the first heat-conductive disk 12 of the first heat-conductive component and the second heat-conductive disk 16 of the second heat-conductive component.

[0197] The opposed ends of the bimetallic strip 20 are secured to the second heat-conductive disk 16 of the second heat-conductive component.

[0198] The aerosol-generating device 2 further comprises a rigid heat-insulative cylindrical sleeve 22 around the second tubular section 8 of the housing 4 and a portion of the first tubular section 6 of the housing 4. The aerosol-generating device also comprises a rigid heat-insulative cylindrical cover 24 removably connected to the heat-insulative sleeve 22. As shown in FIGS. 1b and 1c, when connected to the heat-insulative sleeve 22, the heat-insulative cover 24 projects outwardly beyond the first tubular section 6 of the housing 4. One or more air inlets 26 are provided in the heat-insulative sleeve 22 around the second tubular section 8 of the housing 4. To use the aerosol-generating device 2, the heat-insulative cover 24 is disconnected from the heat-insulative sleeve 22 as shown in FIG. 1a. A solid cylindrical combustible carbonaceous heat source 28 comprising an axial cavity is inserted into the first tubular section 6 of the housing 4. The end face of the combustible heat source 28 abuts the first heat-conductive disk 12 of the first heat-conductive component of the heat-conductive element 10. The first elongate heat-conductive member 14 of the first heat-conductive component of the heat-conductive element 10 projects into the axial cavity of the combustible heat source 28.

[0199] An aerosol-generating article 30 comprising an aerosol-generating substrate 32 is inserted into the second tubular section 8 of the housing 4. The end face of the aerosol-generating substrate 32 of the aerosol-generating article 30 abuts the second heat-conductive disk 16 of the second heat-conductive component of the heat-conductive element 10. The second elongate heat-conductive member 18 of the second heat-conductive component of the heat-conductive element 10 projects into the aerosol-generating substrate 32 of the aerosol-generating article 30.

[0200] The combustible heat source 28 is ignited using a lighter or other suitable device and the heat-insulative cover 24 is then connected to the heat-insulative sleeve 22 as shown in FIG. 1b.

[0201] Initially the bimetallic strip 20 of the heat conductive element 10 is in the first position shown in FIG. 1b. In the first position the bimetallic strip 20 is convexly curved relative to the first tubular section 6 of the housing 4 and is in direct contact with the first heat-conductive disk 12 of the first heat-conductive component of the heat-conductive element 10.

[0202] Following ignition of the combustible heat source 28, the aerosol-generating substrate 32 of the aerosol-generating article 30 in the second tubular section 8 of the housing 4 is heated by conductive heat transfer from the combustible heat source 28 in the first tubular section 6 of the housing 4 via the first tubular section 6 and the second tubular section 8 of the housing 4 and via the heat-conductive element 10. Volatile compounds are released from the heated aerosol-generating substrate 32 and entrained in air drawn through the aerosol-generating article 30. As the released compounds cool, they condense to form an aerosol that is inhaled by the user through the mouth end of the aerosol-generating article 30.

[0203] When the bimetallic strip 20 of the heat-conductive element 10 is heated above a threshold temperature by the combustible heat source 28 it deforms from the first position shown in FIG. 1b to the second position shown in FIG. 1c. In the second position, the bimetallic strip 20 is no longer in direct contact with the first heat-conductive disk 12 of the first heat-conductive component of the heat-conductive element 10 and the aerosol-generating substrate 32 of the aerosol-generating article 30 in the second tubular portion 8 of the housing 4 is no longer heated by conductive heat transfer from the combustible heat source 28 in the first tubular section 6 of the housing 4 via the heat-conductive element 10.

[0204] In the second position, heat is transferred by conduction from the heat-conductive element 10 comprising the bimetallic strip 20 to the aerosol-generating substrate 32 of the aerosol-generating article 30 received in the second tubular section 8 of the housing 4 and the bimetallic strip 20 cools. When the bimetallic strip 20 cools below the threshold temperature, the bimetallic strip 20 deforms from the second position shown in FIG. 1c to the first position shown in FIG. 1b. In the first position, the bimetallic strip is once again in direct contact with the first heat-conductive disk 12 of the first heat-conductive component of the heat-conductive element 10 and the aerosol-generating substrate 32 of the aerosol-generating article 30 is once again heated by conductive heat transfer from the combustible heat source 28 in the first tubular section 6 of the housing 4 via the heat-conductive element 10.

[0205] Once one or both of the combustible heat source and the aerosol-generating substrate 32 of the aerosol-generating article 30 have been consumed, the heat-insulative cover 24 may be disconnected from the heat-insulative sleeve 22 as shown in FIG. 1a. One or both of the combustible heat source 28 and the aerosol-generating article 30 may then be removed from the first tubular section 6 and the second tubular section 8 of the housing 4, respectively.

[0206] To reuse the aerosol-generating device 2, one or both of a further combustible heat source 28 and a further aerosol-generating article 30 may subsequently be inserted into the first tubular section 6 and the second tubular section 8 of the housing 4, respectively.

[0207] The aerosol-generating device 2 according to the second embodiment of the invention shown in FIGS. 2a and 2b is of largely similar construction to the aerosol-generating device according to the first embodiment of the invention shown in FIGS. 1a to 1c. However, in the aerosol-generating device according to the second embodiment of the invention the opposed ends of the bimetallic strip 20 of the heat conductive element 10 are secured to the first heat-conductive disk 12 of the first heat-conductive component.

[0208] Initially the bimetallic strip 20 of the heat conductive element 10 is in the first position shown in FIG. 2a. In the first position the bimetallic strip 20 is flat and in direct contact with the first heat-conductive disk 12 of the first heat-conductive component of the heat-conductive element 10.

[0209] Following ignition of a combustible heat source 28 inserted into the first tubular section 6 of the housing 4, the aerosol-generating substrate 32 of an aerosol-generating article 30 inserted into the second tubular section of the housing 4 is heated by conductive heat transfer from the combustible heat source 28 in the first tubular section 6 of the housing 4 via the first tubular section 6 and the second tubular section 8 of the housing. In the first position, the bimetallic strip is not in direct contact with the second heat-conductive disk 16 of the first heat-conductive component of the heat-conductive element 10 and the aerosol-generating substrate 32 of the aerosol-generating article 30 is not heated by conductive heat transfer from the combustible heat source 28 in the first tubular section 6 of the housing 4 via the heat-conductive element 10.

[0210] Volatile compounds are released from the heated aerosol-generating substrate 32 and entrained in air drawn through the aerosol-generating article 30. As the released compounds cool, they condense to form an aerosol that is inhaled by the user through the mouth end of the aerosol-generating article 30.

[0211] When the bimetallic strip 20 of the heat-conductive element 10 is heated above a threshold temperature by the combustible heat source 28 it deforms from the first position shown in FIG. 2a to the second position shown in FIG. 2b. In the second position, the bimetallic strip is in direct contact with the second heat-conductive disk 16 of the second heat-conductive component of the heat-conductive element 10 and the aerosol-generating substrate 32 of the aerosol-generating article 30 is heated by conductive heat transfer from the combustible heat source 28 in the first tubular section 6 of the housing 4 via the heat-conductive element 10.

[0212] In the second position, the bimetallic strip 20 cools. When the bimetallic strip 20 cools below the threshold temperature, the bimetallic strip 20 deforms from the second position shown in FIG. 2b to the first position shown in FIG. 2a. In the first position, the bimetallic strip 20 is no longer in direct contact with the second heat-conductive disk 16 of the second heat-conductive component of the heat-conductive element 10 and the aerosol-generating substrate 32 of the aerosol-generating article 30 in the second tubular portion 8 of the housing 4 is no longer heated by conductive heat transfer from the combustible heat source 28 in the first tubular section 6 of the housing 4 via the heat-conductive element 10.

[0213] Once one or both of the combustible heat source and the aerosol-generating substrate 32 of the aerosol-generating article 30 have been consumed, the heat-insulative cover 24 may be disconnected from the heat-insulative sleeve 22. One or both of the combustible heat source 28 and the aerosol-generating article 30 may then be removed from the first tubular section 6 and the second tubular section 8 of the housing 4, respectively.

[0214] To reuse the aerosol-generating device 2, one or both of a further combustible heat source 28 and a further aerosol-generating article 30 may subsequently be inserted into the first tubular section 6 and the second tubular section 8 of the housing 4, respectively.

[0215] The aerosol-generating device 2 according to the third embodiment of the invention shown in FIGS. 3a and 3b is of similar construction to the aerosol-generating device according to the first embodiment of the invention shown in FIGS. 1a to 1c. However, in the aerosol-generating device 2 according to the third embodiment of the invention the bimetallic element is in the form of a bimetallic coil 40 and is secured to both the first heat-conductive disk 12 of the first heat-conductive component and the second heat-conductive disk 16 of the second heat-conductive component. In addition, in the aerosol-generating device according to the third embodiment of the invention the first elongate heat-conductive member 14 of the first heat-conductive component of the heat-conductive element 10 is omitted and the first heat-conductive disk 12 of the first heat-conductive component of the heat-conductive element 10 is movable relative to the first tubular section 6 of the housing 4.

[0216] Initially the bimetallic coil 40 of the heat conductive element 10 is in the first position shown in FIG. 3a. In the first position the bimetallic coil 40 is loosely wound and the first heat-conductive disk 12 of the first heat-conductive component of the heat-conductive element 10 is in direct contact with a combustible heat source 28 inserted into the first tubular section 6 of the housing 4.

[0217] Following ignition of the combustible heat source 28, the aerosol-generating substrate 32 of an aerosol-generating article 30 inserted into the second tubular section 8 of the housing 4 is heated by conductive heat transfer from the combustible heat source 28 in the first tubular section 6 of the housing 4 via the first tubular section 6 and the second tubular section 8 of the housing 4 and via the heat-conductive element 10. Volatile compounds are released from the heated aerosol-generating substrate 32 and entrained in air drawn through the aerosol-generating article 30. As the released compounds cool, they condense to form an aerosol that is inhaled by the user through the mouth end of the aerosol-generating article 30.

[0218] When the bimetallic coil 40 of the heat-conductive element 10 is heated above a threshold temperature by the combustible heat source 28 it deforms from the first position shown in FIG. 3a to the second position shown in FIG. 3b. In the second position, the bimetallic coil 40 is tightly wound, the first heat-conductive disk 12 of the first heat-conductive component of the heat-conductive element 10 is no longer in direct contact with the combustible heat source 28 and the aerosol-generating substrate 32 of the aerosol-generating article 30 in the second tubular portion 8 of the housing 4 is no longer heated by conductive heat transfer from the combustible heat source 28 in the first tubular section 6 of the housing 4 via the heat-conductive element 10.

[0219] In the second position, heat is transferred by conduction from the heat-conductive element 10 comprising the bimetallic coil 40 to the aerosol-generating substrate 32 of the aerosol-generating article 30 received in the second tubular section 8 of the housing 4 and the bimetallic coil 40 cools. When the bimetallic coil 40 cools below the threshold temperature, the bimetallic coil 40 deforms from the second position shown in FIG. 3b to the first position shown in FIG. 3a. In the first position, the bimetallic strip is loosely wound, the first heat-conductive disk 12 of the first heat-conductive component of the heat-conductive element 10 is once again in direct contact with combustible heat source 28 and the aerosol-generating substrate 32 of the aerosol-generating article 30 is once again heated by conductive heat transfer from the combustible heat source 28 in the first tubular section 6 of the housing 4 via the heat-conductive element 10.

[0220] Once one or both of the combustible heat source and the aerosol-generating substrate 32 of the aerosol-generating article 30 have been consumed, the heat-insulative cover 24 of the aerosol-generating device 2 may be disconnected from the heat-insulative sleeve 22 thereof. One or both of the combustible heat source 28 and the aerosol-generating article 30 may then be removed from the first tubular section 6 and the second tubular section 8 of the housing 4, respectively.

[0221] To reuse the aerosol-generating device 2, one or both of a further combustible heat source 28 and a further aerosol-generating article 30 may subsequently be inserted into the first tubular section 6 and the second tubular section 8 of the housing 4, respectively.

[0222] In the aerosol-generating devices according to the first, second and third embodiments of the invention shown in FIGS. 1a to 1c, 2a and 2b and 3a and 3b, respectively, deformation of the bimetallic element 20 between the first position and the second position provides thermostatic control of the temperature of the aerosol-generating substrate 32 of the aerosol-generating article 30 received in the second tubular section 8 of the housing 4 through dynamic adjustment of the conductive heat transfer from the combustible heat source 28 received in the first tubular section 6 of the housing 4 to the aerosol-generating substrate 32 of the aerosol-generating 30 via the heat-conductive element. The bimetallic element 20 thereby maintains the temperature of the aerosol-generating substrate 32 of the aerosol-generating article 30 within a certain range in order to optimise the aerosol delivery to the user.