SUSCEPTOR HEATING ELEMENT FORMED FROM SHAPE MEMORY MATERIAL FOR AEROSOL GENERATING DEVICE

Abstract

A susceptor heating element is provided for an aerosol-generating device, the susceptor heating element being configured to heat an aerosol-forming substrate when received in the aerosol-generating device, and the aerosol-forming device including an induction coil configured to generate an alternating magnetic field when an alternating current is provided to the induction coil, the susceptor heating element being formed from a shape-memory material. An aerosol-generating article is also provided.

Claims

1-35. (canceled)

36. A susceptor heating element for an aerosol-generating device, the susceptor heating element being configured to heat an aerosol-forming substrate when received in the aerosol-generating device, and the aerosol-forming device comprising an induction coil configured to generate an alternating magnetic field when an alternating current is provided to the induction coil, wherein the susceptor heating element is formed from a shape-memory material.

37. The susceptor heating element according to claim 36, wherein the susceptor heating element is further configured to recover a corrugated shape in a range around an operating temperature.

38. The susceptor heating element according to claim 37, wherein the range is between 180 degrees Celsius and 400 degrees Celsius.

39. The susceptor heating element according to claim 36, wherein the shape-memory material comprises a shape-memory alloy.

40. The susceptor heating element according to claim 39, wherein the shape-memory alloy is any of: Ti—Ni—Pd, Ni—Ti—Hf, Ni—Ti—Zr, and Cu—Al—Ni.

41. The susceptor heating element according to claim 37, wherein the corrugated shape of the susceptor heating element has a wavy shape having a constant wave pitch.

42. The susceptor heating element according to claim 36, wherein the susceptor heating element has two opposing major surfaces joined by two minor surfaces.

43. The susceptor heating element according to claim 36, wherein the susceptor heating element has a length and a cross-section perpendicular to the length, wherein the cross-section has a width and a depth, and wherein the length of the susceptor heating element is greater than the width of the cross-section, and the width of the cross-section is greater than the depth of the cross-section.

44. The susceptor heating element according to claim 36, wherein the susceptor heating element is in the form of a pin or a rod.

45. An aerosol-generating article, comprising: a plurality of elements assembled in the form of a rod having a mouth end and a distal end upstream from the mouth end, the plurality of elements including an aerosol-forming substrate located at or towards the distal end of the rod, and a susceptor heating element arranged within the rod and in thermal contact with the aerosol-forming substrate, wherein the susceptor heating element is located within the aerosol-forming substrate, and wherein the susceptor heating element is formed from a shape-memory material.

46. The aerosol-generating article according to claim 45 for an aerosol-generating device, wherein the susceptor heating element is configured to recover a corrugated shape in a range around an operating temperature of the aerosol-generating device.

47. The aerosol-generating article according to claim 46, wherein the range is between 180 degrees Celsius and 400 degrees Celsius.

48. The aerosol-generating article according to claim 45, wherein the shape-memory material comprises a shape-memory alloy.

49. The aerosol-generating article according to claim 48, wherein the shape-memory alloy is any of: Ti—Ni—Pd, Ni—Ti—Hf, Ni—Ti—Zr, and Cu—Al—N.

50. The aerosol-generating article according to claim 46, wherein the corrugated shape of the susceptor heating element has a wavy shape having a constant wave pitch.

51. The aerosol-generating article according to claim 45, wherein the susceptor heating element has two opposing major surfaces joined by two minor surfaces.

52. The aerosol-generating article according to claim 45, wherein the susceptor heating element has a length and a cross-section perpendicular to the length, wherein the cross-section has a width and a depth, and wherein the length of the susceptor heating element is greater than the width of the cross-section, and the width of the cross-section is greater than the depth of the cross-section.

53. The aerosol-generating article according to claim 45, wherein the susceptor heating element is in the form of a pin or a rod.

54. The aerosol-generating article according to claim 45, wherein the susceptor heating element is positioned in a radially central position within the rod and extends along a longitudinal axis of the rod.

55. The aerosol-generating article according to claim 45, wherein the aerosol-forming substrate is in the form of a rod comprising a gathered sheet of aerosol-forming material, or in the form of a rod comprising strands of aerosol-forming material, or in the form of a rod comprising a gel of aerosol-forming material.

Description

[0088] The invention will be further described, by way of example only, with reference to the accompanying drawings in which:

[0089] FIG. 1 shows an aerosol-generating device with an inductive heating element;

[0090] FIG. 2 shows corrugated susceptor heating elements of the present invention;

[0091] FIG. 3 shows an aerosol-generating article including a corrugated susceptor heating element; and

[0092] FIG. 4 schematically shows process steps of forming a susceptor heating element of the present invention.

[0093] FIG. 1A and FIG. 1B show an aerosol-generating device 16 with a conventional inductive heating element 10. The inductive heating element 10 comprises an elongate susceptor heating element 12 that is arranged within an induction coil 14. The susceptor heating element 12 is a cylindrical element having a tapered tip. The susceptor heating element 12 and the induction coil 14 have a constant diameter along the longitudinal length of the inductive heating element 10.

[0094] As depicted in FIG. 1A, the aerosol-generating device 16 further comprises a housing 18. The induction coil 14 is arranged within the housing 18. The housing 18 also comprises a chamber 20 at a proximal end in which a consumable can be inserted. In the chamber 20, the susceptor heating element 12 of the conventional heating element 10 is arranged such that the susceptor heating element 12 can penetrate the consumable. In the housing 18 of the aerosol-generating device 16, a battery 22 is arranged as well as a controller 24 for controlling the supply of electrical power from the battery 22 to the conventional inductive heating element 10.

[0095] FIG. 2 shows various susceptor heating elements 12 according to the present invention. The upper view of FIG. 2 shows a susceptor heating element 12 formed from a rod of shape memory alloy. The rod is made from Titanium-Nickel-Paladium alloy and is provided with a corrugation. The susceptor heating element 12 has a wavy shape, with a regular sinusoidal pattern. The pitch p of the sinusoidal shape of the susceptor heating element 12 amounts to about 5 millimeters. In the lower view of FIG. 2 a further susceptor heating element 12 is depicted. This susceptor heating element 12 is formed from the same material but is formed from a foil having a width of 4 millimeters. Depending on the type of aerosol-generating device either of these susceptor heating elements 12 may be used.

[0096] FIG. 3 shows an aerosol-generating article 30 comprising a susceptor heating element 12. The aerosol-generating article 30 comprises a plurality of elements assembled in the form of a rod. The aerosol-generating article 30 has a distal end 32 and a mouth end 34 downstream from the distal end 32.

[0097] From distal end 32 to mouth end 34 the aerosol-generating article 30 comprises a front plug 36, an aerosol-forming portion 38, a first hollow acetate tube 42, a second hollow acetate tube 44 and a mouth piece filter 46.

[0098] The aerosol-forming portion 38 comprises the susceptor heating element 12 which is arranged in thermal contact with an aerosol-forming substrate 40. The aerosol-forming substrate 40 is provided in the form of a plug comprising a gathered sheet of homogenised tobacco material. The tobacco material is circumscribed by a paper wrapper. The same design of an aerosol-generating article may be used with aerosol-forming substrate provided in form of a gel as described above.

[0099] The susceptor heating element 12 is located centrally within the aerosol-forming substrate 40 of the aerosol-forming portion 38, such that any heat from the susceptor heating element 12 is conveyed almost instantaneously to the surrounding aerosol-forming substrate 40.

[0100] The aerosol-generating article 30 is inserted into an aerosol-generating device (not shown) comprising an induction coil configured to generate an alternating magnetic field when an alternating current is provided to the coil. The magnetic field generated by the induction coil of the device is used for generating heat in the susceptor heating element 12 comprised in the aerosol-generating article 30.

[0101] In use of the device, heat generated in the susceptor heating element 12 is used to vaporize volatile components in the aerosol-forming substrate 40. The airflow through the aerosol-generating article 30 carries the generated vapor from the aerosol-forming portion 38 downstream towards the mouth piece filter 46 into the condensation chamber 40, where an inhalable aerosol is formed. The vapor at least partly condenses in the inner volume defined by the first thin hollow acetate tubes 42 to form an aerosol. At the downstream end of the thin hollow acetate tube 42 ventilation holes (not shown) may be provided. The dimensions and the design of the hollow acetate tubes 42, 44 assist in shaping the aerosol to achieve a desired temperature range and droplet size.

[0102] In FIG. 4 the process steps of a manufacturing process for forming a susceptor heating element according to the present invention are indicated.

[0103] In a first step a rod-shaped or foil-shaped raw material of the shape-memory alloy is provided. This shape-memory alloy is then heated to a temperature at or above the transformation temperature of the shape-memory alloy. While the shape-memory alloy is held at this elevated temperature, the shape-memory alloy is formed into the desired shape, which the susceptor heating element is to recover upon use in the aerosol-generating device. After forming the shape-memory alloy into the desired shape, the shape-memory alloy is allowed to cool down. Subsequently the shape-memory alloy is rolled into bobbins for storage and later use. In order to form individual susceptor heating elements, the shape-memory material is rolled from the bobbin and processed into individual susceptor heating elements having a desired length as required by the aerosol-generating system in which the susceptor heating elements are to be used. The susceptor heating element may then be included in the heating chamber of an aerosol-generating device or may be incorporated in an aerosol-generating article of an aerosol-generating system.