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EP-4362724-B1 - HEATING ASSEMBLY FOR AEROSOL GENERATING DEVICE

EP4362724B1EP 4362724 B1EP4362724 B1EP 4362724B1EP-4362724-B1

Inventors

  • HUPKES, ERNST

Dates

Publication Date
20260513
Application Date
20220624

Claims (15)

  1. A heating assembly (10) for an aerosol generating device comprising an elongated heating cup (12) comprising a tubular wall (14) forming a cavity for receiving a tubular aerosol generating article therein and a resistive heater (16) arranged for heating upon application of an electrical current thereto; the resistive heater (16) being arranged in thermal conduction on the outer surface of the tubular wall (14); wherein the tubular wall (14) comprises, at its circumference, a successively circumferential and alternate distribution of substantially planar wall portions (14a) and convex wall portions (14b); wherein the number of substantially planar wall portions (14a) is three or more; wherein the substantially planar wall portions (14a) are substantially planar both at the outer surface and inner surface of the tubular wall (14); and, wherein each substantially planar wall portion is covered by a resistance track (16a) of the heater (16) and the resistance tracks (16a) of different substantially planar wall portions (14a) are connected by lower resistance connection tracks (16b).
  2. Heating assembly (10) according to claim 1, wherein the substantially planar wall portions (14a) are evenly distributed at the circumference of the tubular wall (14).
  3. Heating assembly (10) according to claims 1 or 2, wherein the number of substantially planar wall portions (14a) is from three to five.
  4. Heating assembly (10) according to any of the preceding claims, wherein the resistance tracks (16a) of different substantially planar wall portions (14a) are placed in series or parallel.
  5. Heating assembly (10) according to any of the preceding claims, wherein the lower resistance connection tracks (16b) are positioned on the convex wall portions (14b).
  6. Heating assembly (10) according to any of the preceding claims, wherein the lower resistance connection tracks (16b) are wider than the resistance tracks (16a) on the substantially planar wall sections.
  7. Heating assembly (10) according to any of the preceding claims, wherein the tubular wall (14) comprises a metal or metal alloy of substantially constant thickness.
  8. Heating assembly (10) according to any of the preceding claims, wherein the resistive heater (16) is formed as a thin film wrapped about the tubular wall (14) of the heating cup (12).
  9. Heating assembly (10) according to any of claims 1 to 7, wherein the resistive heater (16) comprises heating tracks printed on the outer surface of the tubular wall (14).
  10. Heating assembly (10) according to any of the preceding claims, wherein the tubular wall (14) has an electrically insulating layer thereon.
  11. Heating assembly (10) according to claim 10, wherein the electrically insulating layer is a coating or polymer film.
  12. Heating assembly (10) according to any of the preceding claims, wherein the substantially planar wall portions (14a) end before a bottom wall of the heating cup (12), the distance between the bottom wall of the heating cup (12) and the end of the substantially planar wall portions (14a) being at least 2 mm.
  13. Heating assembly (10) according to any of the preceding claims, wherein the substantially planar wall portions (14a) are configured to compress an aerosol generating article received in the heating cup (12) at the location of the substantially planar wall portions (14a).
  14. Heating assembly (10) according to any of the preceding claims, wherein the convex wall portions (14b) define an air flow path between an aerosol generating article received in the heating cup (12) and the heating cup (12).
  15. A system (100) comprising an aerosol generating device (110) with a heating assembly (110) as claimed in any one of the preceding claims and an aerosol generating article (120) configured to be inserted in the cavity such that the aerosol generating article (120) is compressed at the location of the substantially planar wall portions (14a).

Description

FIELD The present disclosure relates to a heating assembly for an aerosol generating device. Also provided are systems comprising aerosol generating devices with such heating assemblies and aerosol generating devices. The disclosure is particularly applicable to portable aerosol generation devices, which may be self-contained and of a low temperature. Such devices may heat, rather than burn, tobacco or other suitable aerosolisable materials by conduction, convection, and/or radiation, to generate an aerosol for inhalation. Heating assemblies in accordance with the invention are safe, reliable, easily manufactured, and have low power requirements. BACKGROUND The popularity and use of reduced-risk or modified-risk devices (also known as vaporisers) has grown rapidly in the past few years as an aid to assist habitual smokers wishing to quit smoking traditional tobacco products such as cigarettes, cigars, cigarillos, and rolling tobacco. Various devices and systems are available that heat or warm aerosolisable substances as opposed to burning tobacco as in conventional tobacco products. A commonly available reduced-risk or modified-risk device is the heated substrate aerosol generation device or heat-not-burn device. Devices of this type generate an aerosol or vapour by heating an aerosol generating article that typically comprises moist leaf tobacco or other suitable aerosolisable material to a temperature typically in the range 150°C to 350°C. Heating an aerosol generating article, but not combusting or burning it, releases an aerosol that comprises the components sought by the user but not the toxic and carcinogenic by-products of combustion and burning. Furthermore, the aerosol produced by heating the tobacco or other aerosolisable material does not typically comprise the burnt or bitter taste resulting from combustion and burning that can be unpleasant for the user and so the substrate does not therefore require the sugars and other additives that are typically added to such materials to make the smoke and/or vapour more palatable for the user. However, the heat management of aerosol generating devices can prove problematic, especially during periods of frequent or prolonged use. Furthermore, the power required to heat aerosol generating articles is very high, requiring batteries of conventional devices to be frequently recharged or replaced. It is also desirable to simplify the manufacture of aerosol generating devices. It is an object of the present invention to address the above issues and to provide an aerosol generating device with improved safety and reduced power requirements. WO 2020/074602 A1 discloses an aerosol generation device that has a heating chamber for receiving a substrate carrier containing an aerosol substrate. The heating chamber comprises an open end through which the substrate carrier is insertable in a direction along a length of the heating chamber. A tubular wall defines an interior volume of the heating chamber and a plurality of engagement elements are each formed from a portion of the tubular wall. Each of the plurality of engagement elements is arranged to extend from an interior surface of the tubular wall at a different location around the tubular wall such that a cross sectional area of the interior volume of the heating chamber is reduced for at least a portion of the length of the heating chamber. SUMMARY OF INVENTION According to a first aspect of the invention there is provided a heating assembly for an aerosol generating device comprising an elongated heating cup comprising a tubular wall forming a cavity for receiving a tubular aerosol generating article therein and a resistive heater arranged for heating upon application of an electrical current thereto; the resistive heater being arranged in thermal conduction on the outer surface of the tubular wall; wherein the tubular wall comprises, at its circumference, a successively circumferential and alternate distribution of substantially planar wall portions and convex wall portions; wherein the number of substantially planar wall portions is three or more; and, wherein the substantially planar wall portions are substantially planar both at the outer surface and inner surface of the tubular wall. Each substantially planar wall portion is covered by a resistance track of the heater and the resistance tracks of different substantially planar wall portions are connected by lower resistance connection tracks. Therefore, a tubular aerosol generating article - e.g. a tobacco stick - may be inserted into the heating cup of the heating assembly and heated using the resistive heater to release an aerosol. Subsequently the aerosol may be inhaled by a user. As will be discussed below, such heating assemblies require lower overall temperatures to generate these aerosols and therefore require less power to operate. In addition the heating assemblies are convenient to manufacture and simple to use. The substantially planar wall portio