Induction-heated aerosol generator with a multi-wire induction coil

Abstract

The present invention relates to an aerosol generating device (10) for generating an aerosol by inductively heating an aerosol-forming substrate (97). The device (10) comprises a device housing (19) including a cavity (20). The cavity is configured to removably receive at least a portion of the aerosol-forming substrate (97) to be heated. The aerosol generating device (10) further comprises an induction heating arrangement including an induction coil (31) for generating an alternating magnetic field within the cavity (20). The induction coil (31) is formed by multiple turns of a composite cable (32) disposed around at least a portion of the cavity (20). The composite cable (32) includes an electrical conductor (33) at least partially embedded in an insulated conductor case (34). The conductor (33) includes multiple uninsulated wires (35) in electrical contact with each other.

Description

[Technical Field]

[0001] The present disclosure relates to an inductively heated aerosol generating device for use with a substrate capable of forming an inhalable aerosol upon heating. The present invention further relates to an aerosol generating system comprising such a device and an aerosol-generating article including a heated aerosol-forming substrate. [Background technology]

[0002] Aerosol-generating devices used to generate inhalable aerosols by inductively heating an aerosol-forming substrate are generally known in the prior art. Typically, such devices comprise a cavity for removably receiving the substrate and an induction heating arrangement for generating an alternating magnetic field within the cavity. Within the cavity, the magnetic field is used to induce at least one of heat-generating eddy currents or hysteresis losses within a susceptor, which is then disposed in thermal proximity or direct physical contact with the substrate to be heated. Both the aerosol-forming substrate and the susceptor may be integral parts of an aerosol-generating article receivable within the cavity. Alternatively, only the substrate may be included within the article, and the susceptor may be part of the device.

[0003] To generate an alternating magnetic field within the cavity, an induction heating arrangement typically includes an induction coil formed by multiple turns of an electrical conductor disposed around at least a portion of the cavity. Typically, the volume of the cavity roughly corresponds to the substrate volume of a single user experience and is therefore on the order of several cubic centimeters. This is particularly true for handheld aerosol generating devices. Therefore, the radius of the induction coil is typically small. This significantly complicates the manufacture of the coil or even makes it prone to errors, which can result in a faulty or non-functional device. Additionally, it is often desirable to have electrical conductors with specific cross-sectional profiles, for example, to optimally utilize the limited installation space in such devices. However, electrical conductors with specific cross-sections, such as rectangular cross-sections, are typically more expensive than conductors with standard cross-sections. This can make the manufacture of such devices more cost-intensive.

[0004] Therefore, there is a need for an inductively heated aerosol generator and aerosol generation system that possesses the advantages of prior art solutions while mitigating their limitations. In particular, it would be desirable to have an inductively heated aerosol generator and system that includes an induction coil that can be manufactured in a simple, customized, and cost-effective manner, particularly with a low failure rate. Summary of the Invention

[0005] According to the present invention, there is provided an aerosol generating device for generating an aerosol by inductively heating an aerosol-forming substrate. The device comprises a device housing including a cavity. The cavity is configured to removably receive at least a portion of the aerosol-forming substrate to be heated. The aerosol generating device further comprises an induction heating arrangement including an induction coil for generating an alternating magnetic field within the cavity. The induction coil is formed by multiple turns of a composite cable disposed around at least a portion of the cavity. The composite cable includes an electrical conductor at least partially embedded within an insulated conductor case. The electrical conductor includes multiple uninsulated wires in electrical contact with each other.

[0006] The present invention recognizes that the limitations of induction coils formed by conductors including a single solid wire are primarily due to the rigid characteristics of the solid wire. Particularly at small winding radii, winding a conductor including a single solid wire can cause high mechanical stresses in the wire material, which can result in material fatigue or even material fracture, and thus a defective or non-functioning coil. In contrast, conductors including multiple uninsulated wires electrically contacting each other are more flexible than conductors including solid wires of the same total cross-sectional area. Therefore, winding a conductor including multiple uninsulated wires is simpler and less susceptible to material fatigue or even material fracture. Furthermore, multiple uninsulated wires may be arranged within a composite in various configurations to achieve conductors with different cross-sectional shapes. Advantageously, this enables cost-effective production of induction cables including conductors with customized cross-sectional shapes.

[0007] The plurality of uninsulated wires are in electrical contact with one another so as to act as a single conductor, and in particular have substantially the same electrical properties, in particular substantially the same electrical resistance, as a single conductor having the same total cross-sectional area.

[0008] A plurality of non-insulated wires in electrical contact with one another may also be referred to as a stranded wire. A stranded wire is made up of numerous wires bundled or wound together to form a composite conductor. Thus, electrical conductors according to the present invention may also be referred to as composite (electrical) conductors comprising a plurality of non-insulated wires in electrical contact with one another or comprising stranded wires, respectively.

[0009] In general, multiple uninsulated wires can be arranged in different configurations. The wires may be bundled together, twisted together, braided together, or wound together. Similarly, the wires may run parallel to one another along the length of the composite cable, particularly without crossing one another and without being braided or wound together. In a parallel arrangement, contact between adjacent wires occurs along a line, rather than just at a few points. Advantageously, this results in a larger contact area, which increases electrical contact between the wires compared to contact at only a few points. Furthermore, a linear contact area also reduces mechanical stress between the wires, thus improving the flexibility and bending strength of the conductor.

[0010] The wires extend parallel to one another along the length of the composite cable, either in a single layer on top of one another, or in multiple layers, particularly two, three, or four layers on top of one another, and the layers are preferably arranged parallel to one another. That is, the wires may be arranged parallel and adjacent to one another in a single row or plane. Alternatively, the wires may be arranged parallel and adjacent to one another in multiple rows on top of one another, particularly two, three, or four rows on top of one another.

[0011] In a multi-layer configuration, at least some of the wires of each layer (column) are preferably disposed in grooves formed between adjacent wires of adjacent layers (columns). This staggered arrangement is very compact and therefore allows for a compact design of the conductor.

[0012] The layer or each of the layers may be a flat layer. As used herein, the term flat layer refers to a configuration in which the layer or each of the layers is aligned along a straight line transverse to the cable's longitudinal extension, i.e., transverse to the winding direction of the cable around the cavity, as viewed in a cross-section of the composite cable. In other words, the wires in the layer or each of the layers extend parallel to one another in the same plane. A flat configuration of layers may be particularly advantageous for helically winding the composite cable to form a cylindrical induction coil.

[0013] Similarly, a single layer or each of the multiple layers may be a curved layer. As used herein, the term curved layer refers to a configuration in which the single layer or each of the multiple layers is aligned along a curve that is transverse to the cable's longitudinal extension, i.e., transverse to the winding direction of the cable around the cavity, as seen in a cross-section of the composite cable. In other words, the wires in the single layer or each of the multiple layers extend parallel to one another in the same curved plane. A curved configuration of layers may be particularly advantageous when winding the composite cable around a body that forms a cylindrical cavity, where the outer surface of the body is curved transverse to the winding direction.

[0014] The layer or layers are preferably parallel to the circumferential plane defined by the turns of the composite cable, and in this configuration the radial extension of the induction coil is very compact.

[0015] In any of these layered configurations, the wires do not cross each other and are not braided or wound together. In particular, the wires are not twisted. This further reduces mechanical stress between the wires, resulting in better flexibility and bending strength of the conductor.

[0016] Furthermore, arranging the wires in a layered configuration is particularly suitable for achieving conductors of different cross-sectional shapes. For example, a conductor may include twenty wires extending parallel to one another along the length of the composite cable in two flat layers on top of one another, with each layer including ten wires arranged adjacent to one another. In this configuration, the assembly of all wires can form a conductor having a substantially rectangular cross-section when each wire of one layer is arranged on top of the wires of an adjacent layer. Similarly, the assembly of all wires can form a conductor with a substantially parallelogram-shaped cross-section when the layers are shifted relative to one another so that the wires of one layer are arranged in the grooves formed between adjacent wires of an adjacent layer.

[0017] Each wire of the plurality of wires may have one of a circular outer cross-section, an elliptical outer cross-section, an oval outer cross-section, a rectangular outer cross-section, or a square outer cross-section. Wires having a circular outer cross-section may be preferred for economic reasons due to their good availability as standard wires.

[0018] Each wire of the plurality of wires may have a diameter in the range of 0.2 mm to 2.3 mm, particularly 0.25 mm to 1.2 mm, or 0.15 mm to 1.5 mm, particularly 0.25 mm to 0.75 mm.

[0019] Similarly, each wire of the plurality of wires may have a cross-sectional area in the range of 0.1 square millimeters to 17 square millimeters, particularly 0.2 square millimeters to 4.5 square millimeters, or 0.07 square millimeters to 7 square millimeters, particularly 0.2 square millimeters to 1.8 square millimeters.

[0020] Advantageously, the wires of the electrical conductor are embedded in the material of the insulated conductor case by extrusion or lamination.

[0021] In general, the composite cable may have any outer cross-section transverse to the length extension of the cable or transverse to the winding direction of the cable around the cavity, as seen in a cross-sectional view of the composite cable. For example, the composite cable may have a substantially circular outer cross-section, or a substantially rectangular outer cross-section, or a substantially square outer cross-section, or a substantially elliptical outer cross-section, or a substantially oval outer cross-section, or a substantially parallelogram-shaped outer cross-section, or a substantially trapezoidal outer cross-section, or a substantially arc-shaped outer cross-section. In particular, the composite cable may have a non-circular outer cross-section, such as a substantially rectangular outer cross-section, or a substantially square outer cross-section, or a substantially elliptical outer cross-section, or a substantially oval outer cross-section, or a substantially parallelogram-shaped outer cross-section, or a substantially trapezoidal outer cross-section, or a substantially arc-shaped outer cross-section. A substantially arc-shaped cross-section has the shape of an arc or arc segment.

[0022] The composite cable is preferably a flat composite cable. That is, the outer cross section of the composite cable has a width dimension and a thickness dimension, the thickness dimension being less than the width extension. Advantageously, a flat composite cable allows for a compact design of the induction coil. In this configuration, the composite cable has a non-circular or non-rectangular outer cross section. That is, the outer cross section of the composite cable is neither circular nor rectangular. For example, the outer cross section of the composite cable is substantially rectangular, substantially elliptical, substantially oval, substantially parallelogram-shaped, substantially trapezoidal, or substantially arc-shaped. In this configuration, the composite cable may also be referred to as a multi-wire planar cable or ribbon cable.

[0023] When disposed around the cavity, the composite cable may include a first side facing inward toward the cavity and a second side facing outward away from the cavity, opposite the first side. For example, in the case of a rectangular outer cross-section, the first side corresponds to the side of the rectangular outer cross-section facing inward toward the cavity. Similarly, the second side corresponds to the side of the rectangular outer cross-section opposite the first side, i.e., the side of the rectangular outer cross-section facing outward away from the cavity. In the case of an elliptical outer cross-section, the first side corresponds to the half-side of the elliptical outer cross-section facing inward toward the cavity.

[0024] The outer cross-section of the composite cable, particularly a non-circular outer cross-section, may have a first axis of symmetry, particularly a first axis of symmetry extending radially relative to the turns of the composite cable. In particular, the first axis of symmetry may extend between a first side and a second side of the composite cable. Alternatively or additionally, the outer cross-section of the composite cable, particularly a non-circular outer cross-section, may have a second axis of symmetry extending transversely, particularly perpendicular to the first axis of symmetry. That is, the non-circular outer cross-section of the composite cable may have a second axis of symmetry extending transversely, particularly perpendicular to the radial direction relative to the turns of the composite cable.

[0025] The maximum dimension of the cross section of the composite cable in a radial direction relative to the multiple turns of the composite cable, in particular the maximum dimension of the composite cable along an axis perpendicular to the first side and the second side, in particular the maximum thickness dimension of the cross section of the composite cable, may be in the range of 0.5 mm to 9 mm, in particular 0.7 mm to 9 mm, preferably 0.9 mm to 5 mm.

[0026] Similarly, the maximum dimension of the cross section of the composite cable perpendicular to the radial direction of the multiple turns of the composite cable, particularly the maximum dimension of the composite cable in a direction perpendicular to an axis perpendicular to the first side and the second side, or in a direction parallel to at least one of the first side and the second side, particularly the maximum width dimension of the cross section of the composite cable, may be in the range of 1 millimeter to 7 millimeters, particularly 1.5 millimeters to 5 millimeters.

[0027] The conductors or the circumferential curvature enclosing the conductors may each have any cross-section transverse to the cable's longitudinal extension or transverse to the winding direction of the cable around the cavity, as seen in a cross-section of the composite cable. For example, the conductors may have a substantially circular cross-section. Similarly, the conductors may have a non-circular cross-section, in particular a substantially elliptical cross-section, or a substantially oval cross-section, or a substantially rectangular cross-section, or a substantially square cross-section, or a substantially parallelogram-shaped cross-section, or a substantially trapezoidal cross-section, or a substantially arc-shaped cross-section. A substantially arc-shaped cross-section has the shape of an arc or arc segment. As mentioned above, conductors of different cross-sectional shapes may be realized by corresponding arrangements of multiple uninsulated wires.

[0028] The conductor is preferably a flat conductor. That is, the cross section of the conductor has a width dimension and a thickness dimension, the thickness dimension being less than the width dimension. Advantageously, a flat conductor allows for a compact design of the induction coil. In this configuration, the conductor has a non-circular or non-rectangular outer cross section. That is, the cross section of the conductor is neither circular nor rectangular. For example, the cross section of the conductor is substantially rectangular, substantially elliptical, substantially oval, substantially parallelogram-shaped, substantially trapezoidal, or substantially arc-shaped.

[0029] The maximum dimension of the cross section of the conductor in a radial direction relative to the turns of the composite cable, in particular the maximum thickness dimension of the cross section of the conductor, in particular the maximum thickness dimension of the cross section of the conductor perpendicular to the first side, may be in the range of 0.2 mm to 2.3 mm, in particular 0.25 mm to 1.2 mm.

[0030] Similarly, the maximum dimension of the cross section of the conductor perpendicular to the radial direction for the multiple turns of the composite cable, particularly the maximum width dimension of the cross section of the conductor, particularly the maximum width dimension of the cross section of the conductor parallel to the first side, may be in the range of 0.75 millimeters to 6 millimeters, particularly 1 millimeter to 4 millimeters.

[0031] The conductors may be asymmetrically disposed relative to the outer cross section of the composite cable such that they are closer to a first side of the composite cable facing inward toward the cavity than to a second side of the composite cable facing outward away from the cavity. Thus, the insulating conductor case is primarily positioned toward the second side of the composite cable, and thus further radially outward than the conductors. In particular, the conductors may be asymmetrically disposed relative to a second axis of symmetry of the outer cross section of the composite cable. As mentioned above, the second axis of symmetry may extend transversely to the multiple turns of the composite cable, in particular perpendicular to the radial direction. More specifically, the conductors may be disposed between the first side and the second axis of symmetry. Thus, the insulating conductor case may act as a protective sheath surrounding the conductors when the composite cable is disposed around the cavity. Furthermore, the asymmetrical arrangement reduces the radial distance between the conductors and the cavity, which is advantageous in terms of the magnetic field strength of the alternating magnetic field.

[0032] Additionally or alternatively, the conductors may be arranged asymmetrically with respect to a first axis of symmetry of the outer cross section of the composite cable. As mentioned above, the first axis of symmetry may extend radially with respect to the turns of the composite cable, in particular between the first and second sides of the composite cable.

[0033] Advantageously, the electrical conductors are arranged as closely as possible around the cavity, so that the minimum distance between the electrical conductors and the first side surface may be at most 0.1 mm to 0.5 mm, in particular 0.1 mm to 0.3 mm, or 0.1 mm to 1 mm, in particular 0.2 mm to 0.5 mm.

[0034] According to the invention, the conductor case is electrically insulating in order to electrically insulate adjacent turns of the induction coil from each other and therefore prevent short circuits.

[0035] The insulated conductor case may include a magnetic flux concentrator material. Thus, the insulated conductor case may also act as a magnetic flux concentrator. As used herein, the term "magnetic flux concentrator material" refers to a material that can distort a magnetic field and thus concentrate and guide the magnetic field or lines of force generated by the induction coil. By distorting the magnetic field toward the cavity, the insulated conductor case's magnetic flux concentrator material can advantageously concentrate or focus the magnetic field within the cavity. This can increase the level of heat generated in the susceptor for a given level of power passing through the induction coil compared to an induction coil without a magnetic flux concentrator. Therefore, the efficiency of the aerosol generating device can be improved. Furthermore, by distorting the magnetic field toward the cavity, the insulated conductor case's magnetic flux concentrator material reduces the extent to which the magnetic field propagates beyond the induction coil. That is, the insulated conductor case's magnetic flux concentrator material acts as a magnetic shield. Advantageously, this can reduce undesired magnetic field interference with other sensitive parts of the aerosol generating device, such as a metal outer housing, or with sensitive external components in close proximity to the device.

[0036] In particular, by having the flux concentrator material integrated with the composite cable, it becomes possible to provide both the induction coil and the appropriate flux concentrator in one part, and therefore in one process, which advantageously reduces the effort required to manufacture the aerosol generating device, both in terms of cost and time.

[0037] Furthermore, the magnetic flux concentrator as an integral part of the coil winding provides good shock absorption characteristics. Therefore, compared to other magnetic flux concentrator configurations, such as solid ferrite bodies, it can withstand higher excess force impacts or shocks without breaking. For example, compared to susceptors made from sintered ferrite powder, the magnetic flux concentrator as an integral part of the coil winding provides significantly improved resistance to shock loads, such as those resulting from an accidental drop. Furthermore, the magnetic flux concentrator as an integral part of the coil winding allows for a more compact design of the aerosol generator.

[0038] In particular, the term "magnetic flux concentrator material" refers to a material having a high relative magnetic permeability. As used herein, the term "high relative magnetic permeability" refers to a relative magnetic permeability of at least 1000, preferably at least 10,000. These exemplary values ​​refer to the maximum relative magnetic permeability at frequencies up to 50 kHz and a temperature of 25°C. Thus, a magnetic flux concentrator material may include a material having a relative magnetic permeability of at least 1000, preferably at least 10,000, at frequencies up to 50 kHz and a temperature of 25°C. As used herein and in the art, the term "relative magnetic permeability" refers to the ratio of the magnetic permeability of a material or medium, such as a magnetic flux concentrator, to the magnetic permeability of free space, "μ", where μ is 4π·10-7 N·A-2 (4·Pi·10E-07 Newtons per square ampere).

[0039] In general, the insulated conductor case may include or be made of any material or combination of materials suitable for providing magnetic flux concentrator properties. In particular, the insulated conductor case may include a magnetic flux concentrator material held in a matrix. The matrix may include a binder, for example, a polymer (such as silicone). Thus, the matrix may be a polymeric matrix, such as a silicone matrix.

[0040] The insulated conductor casing, and in particular the magnetic flux concentrator material, may comprise a ferrimagnetic or ferromagnetic material, such as, for example, a ferrite material, such as ferrite particles or ferrite powder held in a matrix, or any other suitable material, including a ferromagnetic material, such as iron, ferromagnetic steel, iron silicon, or ferromagnetic stainless steel. Similarly, the insulated conductor casing, and in particular the magnetic flux concentrator material, may comprise a ferrimagnetic or ferromagnetic material, such as ferrimagnetic or ferromagnetic particles or ferrimagnetic or ferromagnetic powder held in a matrix.

[0041] The ferromagnetic material may include at least one metal selected from iron, nickel, and cobalt, and combinations thereof, and may include other elements such as chromium, copper, molybdenum, manganese, aluminum, titanium, vanadium, tungsten, tantalum, silicon, etc. The ferromagnetic material may include about 78 weight percent to about 82 weight percent nickel, 0 to 7 weight percent molybdenum, and the balance iron.

[0042] For example, the insulated conductor case, particularly the magnetic flux concentrator material, may comprise a lamination, pure ferrite, or proprietary iron or ferrite-based composition. More specifically, the insulated conductor case, particularly the magnetic flux concentrator material, may comprise a lamination, pure ferrite, or proprietary iron or ferrite-based composition available under the trade names Fluxtrol 100, Fluxtrol A, Fluxtrol 50, Ferrotron 559H manufactured by Fluxtrol, Alphaform LF, and Alphaform MF from Fluxtrol Inc., 1388 Atlantic Blvd., Auburn Hills, MI 48326 USA.

[0043] The materials Fluxtrol 100, Fluxtrol A, and Fluxtrol 50 contain electrically insulated iron particles and an organic binder. They are suitable for different frequency ranges. Fluxtrol 100 and Fluxtrol A are particularly suitable for frequencies up to 50 kHz, while Fluxtrol 50 is suitable for frequencies between 10 kHz and 1000 kHz. All three materials are characterized by good mechanical strength, machinability, and thermal conductivity.

[0044] Ferrotron 559H contains electrically insulated iron particles and an organic binder, but contains more binder by volume than the previously mentioned Fluxtrol materials. Ferrotron 559H is suitable for medium to high frequencies in materials from 10 kHz to 3000 kHz.

[0045] Alphaform LF and Alphaform MF are formable soft magnetic composites developed based on magnetic particles with a thermoset epoxy binder. Alphaform LF is suitable for frequencies from 1 kHz to 80 kHz, while Alphaform MF is suitable for frequencies from 10 kHz to 1000 kHz.

[0046] Alternatively or additionally, the insulated conductor case, particularly the magnetic flux concentrator material, may comprise at least one of mu-metal or permalloy. Mu-metal is a soft, ferromagnetic nickel-iron alloy with a very high magnetic permeability of approximately 80,000-100,000. For example, mu-metal may comprise approximately 77 weight percent nickel, 16 weight percent iron, 5 weight percent copper, and 2 weight percent chromium or molybdenum. Similarly, mu-metal may comprise 80 weight percent nickel, 5 weight percent molybdenum, small amounts of various other elements such as silicon, and the remaining 12-15 weight percent iron. Permalloy is a nickel-iron magnetic alloy that typically contains additional elements such as molybdenum, copper, and / or chromium.

[0047] To increase the magnetic flux between the insulated conductor cases of adjacent turns of the induction coil, the turns are preferably in physical contact with one another, i.e., the turns abut one another. In particular, the turns can be in physical contact with one another so that at least the insulated conductor cases of adjacent turns are in contact with one another, i.e., abut one another. However, it is also possible for a small gap to exist between adjacent turns of the induction coil. The gap may be up to 0.75 millimeters, in particular up to 0.5 millimeters, and preferably up to 0.25 millimeters.

[0048] Although the conductor case may comprise a metallic, and therefore electrically conductive, material, the conductor case as a whole is still electrically insulating, i.e., non-conductive, to prevent short circuits between adjacent turns of the induction coil.

[0049] According to a particular aspect of the present invention, the composite cable may be a multi-layer composite cable, including an electrically insulating conductor casing layer that forms an insulating conductor casing, and further including at least one of a support layer, a magnetic flux concentrator layer, or a shielding layer. The layered construction of the composite cable allows for several functions to be implemented in one cable, particularly in one process. Advantageously, this reduces the effort required to manufacture the aerosol generating device, both in terms of cost and time.

[0050] The support layer primarily functions to increase the mechanical resistance of the composite cable. Preferably, the support layer does not affect the induction of a magnetic field generated by a current passing through the conductor. That is, the support layer is preferably electromagnetically inert. Therefore, the support layer preferably comprises an electromagnetically inert material, in particular at least one of polyetheretherketone or polyaryletherketone.

[0051] The support layer may have a layer thickness of 0.1 mm to 1 mm, in particular 0.2 mm to 0.5 mm, or 0.25 mm to 1 mm, in particular 0.25 mm to 0.5 mm. On the one hand, these thicknesses are large enough to ensure sufficient mechanical resistance. On the other hand, these thicknesses are still small enough to keep the radial extension of the coil winding as small as possible in order to optimally use the limited installation space in such devices.

[0052] The support layer is preferably disposed on the side of the insulated conductor case layer that faces inward toward the cavity when the composite cable is disposed around the cavity.

[0053] The conductors may be partially embedded in the support layer, i.e., the support layer may cover at least a portion of the conductors, and in particular, the support layer may cover at least the side of the conductors that faces inward toward the cavity when the composite cable is disposed around the cavity.

[0054] Even more preferably, the support layer is an edge layer, especially an edge layer that forms a first side of the composite cable.

[0055] The flux concentrator layer is configured to distort the magnetic field and therefore act as a magnetic flux concentrator capable of focusing and directing the magnetic field generated by the induction coil within the cavity, as described above with respect to the magnetic flux concentrator material optionally included within the insulated conductor case. In this regard, the magnetic flux concentrator layer may preferably be provided in place of the magnetic flux concentrator material included within the insulated conductor case. Advantageously, this may help to avoid potential problems with using a conductive magnetic flux concentrator material, such as a metallic magnetic flux concentrator material, within a conductor case that is generally considered electrically insulating to prevent short circuits between adjacent turns of the induction coil. However, the insulated conductor case layer may also include a magnetic flux concentrator material in addition to the magnetic flux concentrator layer.

[0056] To act as a magnetic flux concentrator, the magnetic flux concentrator layer may comprise a magnetic flux concentrator material, in particular any one of the magnetic flux concentrator materials described above with respect to the insulated conductor case, the details of which are described herein and apply equally to the magnetic flux concentrator layer.

[0057] The magnetic flux concentrator layer is preferably disposed on the side of the insulated conductor casing layer that faces outward, away from the cavity, when the composite cable is disposed about the cavity.

[0058] The shielding layer may function to reduce the adverse effects of magnetic fields in areas outside the shielding layer and, conversely, to reduce distortion of the magnetic field by conductive or highly magnetically susceptible materials in the immediate vicinity of the device or in the housing of the device itself.

[0059] To this end, the shielding layer may include a conductive material such as a metal. In particular, the shielding layer may include at least one of aluminum, copper, tin, steel, gold, silver, a conductive polymer, ferrite, or any combination thereof. For example, the shielding layer may be a metal coating applied to a side of the electrically insulated conductor casing layer facing outward, away from the cavity, when the composite cable is disposed around the cavity. The metal coating may be applied in any suitable manner, such as, for example, with metallic paint, metallic ink, or by a vapor deposition process.

[0060] The shielding layer is preferably disposed on the side of the insulated conductor casing layer that faces outward, away from the cavity, when the composite cable is disposed around the cavity. The shielding layer may preferably be an edge layer, particularly an edge layer that forms the second side of the composite cable.

[0061] When the multi-layer composite cable includes both a magnetic flux concentrator layer and a shielding layer, the magnetic flux concentrator layer is preferably disposed on top of the electrically insulating conductor casing layer (preferably on the side of the insulating conductor casing layer facing outward, away from the cavity, when the composite cable is disposed around the cavity), and the shielding layer is preferably disposed on top of the magnetic flux concentrator layer so as to be an edge layer, in particular an edge layer forming the second side of the composite cable.

[0062] To improve the shielding effect, the induction coil may be additionally surrounded by a conductive tube, sleeve, tape or foil, preferably in physical contact with the shielding layer of each turn of the induction coil.

[0063] The shielding layer may have a layer thickness of 0.3 mm to 3 mm, in particular 0.3 mm to 2 mm, or 0.25 mm to 5.5 mm, in particular 0.25 mm to 1.75 mm, which are well suited to keeping the radial extension of the coil winding as small as possible while still allowing a sufficient shielding effect.

[0064] Similarly, the magnetic flux concentrator layer may have a thickness in the range of 0.3 millimeters to 3 millimeters, particularly 0.3 millimeters to 2 millimeters, or 0.25 millimeters to 5.5 millimeters, particularly 0.25 millimeters to 1.75 millimeters.

[0065] The insulating conductor casing layer may have a layer thickness in the range of 0.2 mm to 6 mm, in particular 0.4 mm to 2 mm, or 0.15 mm to 3 mm, in particular 0.3 mm to 1 mm, or 0.25 mm to 3 mm, in particular 0.3 mm to 1.5 mm, or 0.5 mm to 7 mm, in particular 0.7 mm to 4 mm, or 0.7 mm to 3 mm, or 0.4 mm to 9.2 mm, in particular 0.45 mm to 3.1 mm, or 0.4 mm to 7.2 mm, in particular 0.45 mm to 2.6 mm, or 0.45 mm to 3.7 mm, in particular 0.5 mm to 2.85 mm.

[0066] The portion of the insulating conductor case layer that embeds the conductor on the side opposite the first side may have a thickness of 0.2 to 7 mm, particularly 0.2 to 2 mm, or 0.25 to 1.5 mm, particularly 0.25 to 0.75 mm, or 0.2 to 5 mm, particularly 0.2 to 1.5 mm, which are particularly suitable for ensuring sufficient magnetic flux concentration of the magnetic field when the insulating conductor case includes a magnetic flux concentration material.

[0067] The conductor may be completely embedded in the insulated conductor case, or alternatively, the conductor may be partially embedded in the insulated conductor case, in particular partially embedded in the insulated conductor case layer and in the support layer, such that the conductor is completely surrounded by the insulated conductor case, in particular the insulated conductor case layer, and the support layer.

[0068] The aerosol-generating device may further comprise at least one susceptor that is part of the device. Alternatively, the at least one susceptor may be an integral part of the aerosol-generating article that includes the heated aerosol-forming substrate. As part of the device, the at least one susceptor is disposed or disposable at least partially within the cavity so as to be in thermal proximity or thermal contact, preferably physical contact, with the aerosol-forming substrate during use.

[0069] The susceptor may be formed from any material that can be inductively heated to a temperature sufficient to generate an aerosol from the aerosol-forming substrate. Preferred susceptors include metal or carbon. Preferred susceptors may include ferromagnetic materials, such as ferritic iron, or ferromagnetic steel or stainless steel. Suitable susceptors may be or include aluminum. Preferred susceptors may be formed from 400 series stainless steel, such as grade 410, grade 420, or grade 430 stainless steel.

[0070] The susceptor can include a variety of geometric configurations. The susceptor can include or be a susceptor pin, susceptor rod, susceptor blade, susceptor strip, or susceptor plate. If the susceptor is part of an aerosol-generating device, the susceptor pin, susceptor rod, susceptor blade, susceptor strip, or susceptor plate can preferably protrude into a cavity of the device toward an opening of the cavity that is used to insert the aerosol-generating article into the cavity.

[0071] The susceptor may include or be a filament susceptor, a mesh susceptor, or a wick susceptor.

[0072] Similarly, the susceptor may include or be a susceptor sleeve, susceptor cup, cylindrical susceptor, or tubular susceptor, the interior cavity of which is preferably configured to removably receive at least a portion of the aerosol-generating article.

[0073] The susceptors described above may have any cross-sectional shape, such as, for example, circular, oval, square, rectangular, triangular, or any other suitable shape.

[0074] In addition to the induction coil, the induction heating arrangement may include an alternating current (AC) generator. The AC generator may be powered by a power supply of the aerosol generating device. The AC generator is operably coupled to at least one induction coil. In particular, the at least one induction coil may be an integral part of the AC generator. The AC generator is configured to generate a high-frequency oscillating current that passes through the induction coil to generate an alternating electromagnetic field. The AC current may be supplied to the induction coil continuously after activation of the system, or may be supplied intermittently (e.g., with each puff).

[0075] The induction heating arrangement preferably includes a DC / AC converter connected to a DC power supply including an LC network, the LC network comprising a series connection of a capacitor and an induction coil.

[0076] The induction heating arrangement is preferably configured to generate a high frequency electromagnetic field, which as referred to herein may be in the range of 500 kHz (kilohertz) to 30 MHz (megahertz), in particular 5 MHz (megahertz) to 15 MHz (megahertz), preferably 5 MHz (megahertz) to 10 MHz (megahertz).

[0077] The aerosol-generating device may further include a controller configured to control the operation of the device. In particular, the controller may be configured to control the operation of the induction heating arrangement, preferably in a closed-loop configuration, to control the heating of the aerosol-forming substrate to a predetermined operating temperature. The operating temperature used to heat the aerosol-forming substrate may be at least 180°C, particularly at least 300°C, preferably at least 350°C, more preferably at least 370°C, and most preferably at least 400°C. These temperatures are typical operating temperatures for heating but not burning the aerosol-forming substrate. The operating temperature is preferably in the range of 180°C to 370°C, particularly 180°C to 240°C, or 280°C to 370°C. Generally, the operating temperature may depend on at least one of the type of aerosol-forming substrate to be heated, the configuration of the susceptor, and the arrangement of the susceptor relative to the aerosol-forming substrate during use of the system. For example, when the susceptor is configured and arranged to surround the aerosol-forming substrate when the system is in use, the operating temperature may be within a range of 180°C to 240°C. Similarly, when the susceptor is configured and arranged to be disposed within the aerosol-forming substrate when the system is in use, the operating temperature may be within a range of 280°C to 370°C. The above-mentioned operating temperatures preferably refer to the temperature of the susceptor when in use.

[0078] The controller may comprise a microprocessor, e.g., a programmable microprocessor, microcontroller, or application specific integrated circuit chip (ASIC) or other electronic circuitry capable of providing control. The controller may include further electronic components, such as at least one DC / AC inverter and / or power amplifier, e.g., a class C, class D, or class E power amplifier. In particular, the induction heating arrangement may be part of the controller.

[0079] The aerosol generating device may include a power source, particularly a DC power source configured to provide a DC supply voltage and a DC supply current to the induction heating arrangement. The power source is preferably a battery, such as a lithium iron phosphate battery. Alternatively, the power source may be another form of charge storage device, such as a capacitor. The power source may require recharging, i.e., the power source may be rechargeable. The power source may have a capacity that allows for storage of energy sufficient for one or more user experiences. For example, the power source may have a capacity sufficient to allow continuous generation of aerosol for approximately six minutes, or a multiple of six minutes. In another embodiment, the power source may have a capacity sufficient to allow for a predetermined number of puffs, or for discontinuous activation of the induction heating arrangement.

[0080] The aerosol generating device may comprise a main body that preferably contains at least one of the induction heating arrangements, in particular at least one induction coil, a controller, a power supply, and at least a portion of the cavity.

[0081] In addition to the main body, the aerosol-generating device may further include a mouthpiece, particularly if the aerosol-generating article used with the device does not include a mouthpiece. The mouthpiece may be mounted to the main body of the device. The mouthpiece may be configured to close the cavity when the mouthpiece is attached to the main body. To attach the mouthpiece to the main body, the proximal end portion of the main body may include a magnetic or mechanical mount, such as a bayonet mount or a snap-fit ​​mount, that engages with a corresponding counterpart at the distal end portion of the mouthpiece. If the device does not include a mouthpiece, the aerosol-generating article used with the aerosol-generating device may include a mouthpiece, such as a filter plug.

[0082] The aerosol generating device may comprise at least one air outlet, for example an air outlet in the mouthpiece (if present).

[0083] The aerosol-generating device preferably comprises an air path extending from at least one air inlet, through the cavity, and optionally further to an air outlet in the mouthpiece, if present. The aerosol-generating device preferably comprises at least one air inlet in fluid communication with the cavity. As a result, the aerosol-generating system may comprise an air path extending from the at least one air inlet into the cavity, and optionally further through an aerosol-forming substrate within the article and the mouthpiece and into the user's mouth.

[0084] According to another aspect of the invention, the apparatus may include an induction module defining at least a portion of the cavity. The induction coil may be disposed on an inner surface of the induction module. Alternatively, the induction coil may be disposed on an outer surface of the induction module. In particular, the induction coil may be disposed in a recess, such as an annular recess, in the inner or outer surface of the induction module.

[0085] The guide module may be a sleeve-shaped guide module, in particular a cylindrical guide module, so as to define a cylindrical cavity. The guide module is preferably arranged, in particular removably arranged, in the device housing.

[0086] In this regard, the present invention also provides an induction module disposable within an aerosol-generating device so as to form or be circumferentially disposed around at least a portion of a cavity of the device, the cavity being configured to removably receive an aerosol-forming substrate to be inductively heated. The induction module includes at least one induction coil for generating an alternating electromagnetic field within the cavity in use, the at least one induction coil being disposed around at least a portion of the cavity when the induction module is disposed within the device. The induction coil is formed by multiple turns of a composite cable disposed around at least a portion of the cavity, the composite cable including an electrical conductor at least partially embedded in an insulated conductor case, the conductor including multiple uninsulated wires in electrical contact with each other.

[0087] Further features and advantages of the induction module, in particular the induction coil and composite cable, have been described with respect to the aerosol generating device and will not be repeated.

[0088] According to the present invention, there is also provided an aerosol generation system comprising an aerosol generating device according to the present invention and as described herein. The system further comprises an aerosol-generating article for use with the device, the article comprising an aerosol-forming substrate that is inductively heated by the device. The aerosol-generating article is received or receivable at least partially within the cavity of the device.

[0089] As previously mentioned, the at least one susceptor used to inductively heat the aerosol-forming substrate may be an integral part of the aerosol-generating article rather than being part of the aerosol-generating device. Thus, the aerosol-generating article may comprise at least one susceptor positioned in thermal proximity or thermal contact with the aerosol-forming substrate such that, in use, the susceptor can be inductively heated by the inductive heating arrangement when the article is received in a cavity of the device.

[0090] Further features and advantages of the aerosol generating system according to the present invention have been described in relation to the aerosol generating device and will not be repeated here.

[0091] The term "aerosol-generating device" as used herein generally refers to an electrically operated device capable of interacting with at least one aerosol-forming substrate, particularly an aerosol-forming substrate provided within an aerosol-generating article, to generate an aerosol by heating the substrate. The aerosol-generating device is preferably a smoking device for generating an aerosol that can be directly inhaled by a user through the user's mouth. In particular, the aerosol-generating device is a handheld aerosol-generating device.

[0092] As used herein, the term "susceptor" refers to an element capable of converting electromagnetic energy into heat when subjected to an alternating magnetic field. This can be the result of hysteresis loss and / or eddy currents induced in the susceptor, depending on the electrical and magnetic properties of the susceptor material. Hysteresis loss occurs in ferromagnetic or ferrimagnetic susceptors due to magnetic domains in the material being switched under the influence of the alternating electromagnetic field. Eddy currents may be induced if the susceptor is electrically conductive. In the case of electrically conductive ferromagnetic or ferrimagnetic susceptors, heat can be generated by both eddy currents and hysteresis loss.

[0093] As used herein, the term "aerosol-generating article" refers to an article comprising at least one aerosol-forming substrate that, when heated, releases a volatile compound capable of forming an aerosol. The aerosol-generating article is preferably a heated aerosol-generating article. That is, an aerosol-generating article comprising at least one aerosol-forming substrate intended to be heated, rather than combusted, to release a volatile compound capable of forming an aerosol. The aerosol-generating article may be a consumable product, particularly one that is disposed of after a single use. For example, the article may be a cartridge containing a liquid aerosol-forming substrate to be heated. Alternatively, the article may be a rod-shaped article (particularly a tobacco article) resembling a conventional cigarette. As mentioned above, the article may comprise at least one susceptor positioned in thermal proximity or thermal contact with the aerosol-forming substrate such that, during use, the susceptor can be inductively heated by an induction heating arrangement when the article is received in a cavity of the device.

[0094] As used herein, the term "aerosol-forming substrate" refers to a substrate formed from or including an aerosol-forming material capable of releasing a volatile compound upon heating to form an aerosol. The aerosol-forming substrate is intended to be heated, rather than combusted, to release the aerosol-forming volatile compound. The aerosol-forming substrate may be a solid aerosol-forming substrate, a liquid aerosol-forming substrate, or a gel-like aerosol-forming substrate, or any combination thereof. That is, the aerosol-forming substrate may include both solid and liquid components. The aerosol-forming substrate may include a tobacco-containing material containing volatile tobacco flavor compounds that are released from the substrate upon heating. Alternatively, or additionally, the aerosol-forming substrate may include a non-tobacco material. The aerosol-forming substrate may further include an aerosol former. Examples of suitable aerosol formers are glycerin and propylene glycol. The aerosol-forming substrate may also include other additives and ingredients, such as nicotine or flavoring agents. The aerosol-forming substrate may also be a paste-like material, a sachet of porous material containing the aerosol-forming substrate, or loose tobacco mixed with, for example, a gelling or adhesive agent, which may include a common aerosol former such as glycerin, which is compressed or molded into a plug.

[0095] As used herein, the term "aerosol-generating system" refers to the combination of an aerosol-generating article as further described herein and an aerosol-generating device according to the present invention as described herein, in which the article and device cooperate to generate a respirable aerosol.

[0096] The following non-limiting examples are provided in a non-exhaustive manner, any one or more features of which may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0097] Example 1: 1. An aerosol generating apparatus for generating an aerosol by inductive heating of an aerosol-forming substrate, the apparatus comprising: a device housing including a cavity configured to removably receive at least a portion of an aerosol-forming substrate to be heated; An aerosol generating device comprising: an induction heating arrangement including an induction coil for generating an alternating magnetic field within a cavity, the induction coil being formed by multiple turns of a composite cable arranged around at least a portion of the cavity, the composite cable including a conductor at least partially embedded in an insulated conductor case, the conductor including multiple uninsulated wires in electrical contact with each other. Example 2: 2. An aerosol generating device according to example 1, wherein the wires extend parallel to one another along the length of the composite cable. Example 3: 3. An aerosol generating device according to any one of embodiments 1 or 2, wherein the wires extend parallel to each other along the length of the composite cable in a single layer. Example 4: An aerosol generating device according to any one of embodiments 1 or 2, wherein the wires extend parallel to each other along the length of the composite cable in multiple layers on top of each other, in particular in two, three or four layers on top of each other. Example 5: An aerosol generating device according to any one of Examples 4 and 5, wherein at least a portion of the wires of each layer are disposed in grooves formed between adjacent wires of adjacent layers. Example 6: 6. An aerosol-generating device according to any one of Examples 3 to 5, wherein the layer or layers are each flat layers. Example 7: 6. An aerosol generating device according to any one of Examples 3 to 5, wherein the layer or each of the layers is a curved layer. Example 8: An aerosol generating device according to any one of Examples 3 to 7, wherein the layer or layers are each parallel to a circumferential plane defined by the multiple turns of the composite cable. Example 9: An aerosol generating device according to any one of the embodiments, wherein each wire of the plurality of wires has a circular outer cross section, or an elliptical outer cross section, or an oval outer cross section, or a rectangular outer cross section, or a square outer cross section. Example 10: An aerosol generating device according to any one of the preceding embodiments, wherein each wire of the plurality of wires has a diameter in the range of 0.2 mm to 2.3 mm, in particular 0.25 mm to 1.2 mm, or 0.15 mm to 1.5 mm, in particular 0.25 mm to 0.75 mm. Example 11: An aerosol generating device according to any one of the preceding embodiments, wherein each wire of the plurality of wires has a cross-sectional area in the range of 0.1 square millimeters to 17 square millimeters, in particular 0.2 square millimeters to 4.5 square millimeters, or 0.07 square millimeters to 7 square millimeters, in particular 0.2 square millimeters to 1.8 square millimeters. Example 12: An aerosol generating device according to any one of the preceding embodiments, wherein the composite cable is a flat composite cable. Example 13: 13. The aerosol generating device according to any one of Examples 1 to 12, wherein the composite cable has a circular cross section. Example 14: An aerosol generating device according to any one of Examples 1 to 12, wherein the composite cable has a non-circular outer cross-section, in particular a substantially rectangular outer cross-section, or a substantially square outer cross-section, or a substantially elliptical outer cross-section, or a substantially oval outer cross-section, or a substantially parallelogram-shaped cross-section, or a substantially trapezoidal outer cross-section, or a substantially arc-shaped outer cross-section. Example 15: An aerosol generating device according to any one of the preceding embodiments, wherein the composite cable disposed around the cavity includes a first side facing inward toward the cavity and a second side opposite the first side facing outward away from the cavity. Example 16: An aerosol generating device according to any one of the preceding embodiments, wherein the outer cross-section of the composite cable, in particular the non-circular outer cross-section, has a first axis of symmetry, in particular a first axis of symmetry extending between a first side and a second side extending radially relative to the multiple turns of the composite cable. Example 17: An aerosol generating device according to Example 16, wherein the outer cross section of the composite cable, in particular the non-circular outer cross section, has a second axis of symmetry in the transverse direction, in particular perpendicular to the first axis of symmetry. Example 18: An aerosol generating device according to any one of the preceding embodiments, wherein the maximum dimension of the cross section of the composite cable in a radial direction relative to the multiple windings of the composite cable, in particular the maximum dimension of the composite cable along an axis perpendicular to the first side and the second side, in particular the maximum thickness dimension of the cross section of the composite cable, is in the range of 0.5 millimeters to 9 millimeters, in particular 0.7 millimeters to 9 millimeters, preferably 0.9 millimeters to 5 millimeters. Example 19: An aerosol generating device according to any one of the preceding embodiments, wherein the maximum dimension of the cross section of the composite cable perpendicular to the radial direction of the multiple windings of the composite cable, in particular the maximum dimension of the composite cable in a direction perpendicular to an axis perpendicular to the first side and the second side, or in a direction parallel to at least one of the first side and the second side, in particular the maximum width dimension of the cross section of the composite cable, is in the range of 1 millimeter to 7 millimeters, in particular 1.5 millimeters to 5 millimeters. Example 20: An aerosol generating device according to any one of Examples 1 to 19, wherein the electrical conductor has a substantially circular outer cross section. Example 21: An aerosol generating device according to any one of Examples 1 to 19, wherein the conductor has a non-circular outer cross-section, in particular a substantially rectangular outer cross-section, or a substantially square outer cross-section, or a substantially elliptical outer cross-section, or a substantially oval outer cross-section, or a substantially parallelogram-shaped outer cross-section, or a substantially trapezoidal outer cross-section, or a substantially arc-shaped outer cross-section. Example 22: An aerosol generating device according to any one of the preceding embodiments, wherein the electrical conductor is a flat electrical conductor. Example 23: An aerosol generating device according to any one of the preceding embodiments, wherein the maximum dimension of the cross section of the conductor in a radial direction relative to the multiple turns of the composite cable, in particular the maximum thickness dimension of the cross section of the conductor, in particular the maximum thickness dimension of the cross section of the conductor perpendicular to the first side, may be in the range of 0.2 millimeters to 2.3 millimeters, in particular 0.25 millimeters to 1.2 millimeters. Example 24: An aerosol generating device according to any one of the preceding embodiments, wherein the maximum dimension of the cross section of the conductor perpendicular to the radial direction of the multiple windings of the composite cable, in particular the maximum width dimension of the cross section of the conductor, in particular the maximum width dimension of the cross section of the conductor parallel to the first side, may be in the range of 0.75 millimeters to 6 millimeters, in particular 1 millimeter to 4 millimeters. Example 25: An aerosol generating device according to any one of the preceding embodiments, wherein the composite cable arranged around the cavity includes a first side facing inward toward the cavity and a second side opposite the first side facing outward away from the cavity, and the conductor is arranged asymmetrically with respect to the outer cross section of the composite cable, in particular with respect to a second axis of symmetry of the outer cross section of the composite cable extending transversely, in particular perpendicular to the radial direction relative to the multiple windings of the composite cable, so as to be closer to the first side than to the second side of the composite cable. Example 26: An aerosol generating device according to any one of the preceding embodiments, wherein the minimum distance between the conductor and the first side of the cable facing inward towards the cavity is at most in the range of 0.1 millimeters to 0.5 millimeters, in particular 0.1 millimeters to 0.3 millimeters, or 0.1 millimeters to 1 millimeter, in particular 0.2 millimeters to 0.5 millimeters. Example 27: An aerosol generating device according to any one of the preceding embodiments, wherein the insulated conductive casing comprises a magnetic flux concentrator material. Example 28: 28. The aerosol generating device according to example 27, wherein the magnetic flux concentrator material is held in a substrate. Example 29: An aerosol generating device according to any one of the previous embodiments, wherein the insulated conductor casing, in particular the magnetic flux concentrator material, comprises at least one of a ferrimagnetic material, or a ferromagnetic material, or a mu-metal, or a permalloy. Example 30: An aerosol generating device according to any one of the preceding embodiments, wherein the insulated conductor casing, in particular the magnetic flux concentrator material, comprises a material having a maximum relative magnetic permeability of at least 1000, preferably at least 10000, at a frequency of up to 50 kHz and a temperature of 25°C. Example 31: An aerosol generating device according to any one of the preceding embodiments, wherein the plurality of turns are in contact with each other, preferably abutting each other. Example 32: An aerosol generating device according to any one of the preceding embodiments, wherein the composite cable is a multi-layer composite cable including an electrically insulating conductor case layer that forms an insulating conductor case, and further including at least one of a support layer, a magnetic flux concentrator layer, or a shielding layer. Example 33: 33. An aerosol generating device according to embodiment 32, wherein the support layer comprises an electromagnetically inert material, in particular at least one of polyetheretherketone or polyaryletherketone. Example 34: An aerosol generating device according to any one of Examples 32 or 33, wherein the support layer has a layer thickness in the range of 0.1 millimeter to 1 millimeter, in particular 0.2 millimeter to 0.5 millimeter, or 0.25 millimeter to 1 millimeter, in particular 0.25 millimeter to 0.5 millimeter. Example 35: An aerosol generating device according to any one of Examples 32 to 34, wherein the conductor is partially embedded in the support layer. Example 36: An aerosol generating device according to any one of Examples 32 to 35, wherein the support layer is an edge layer, in particular an edge layer forming a first side of the composite cable. Example 37: An aerosol generating device according to any one of Examples 32 to 36, wherein the shielding layer comprises at least one of a conductive material, in particular aluminum, copper, tin, steel, gold, silver, a conductive polymer, ferrite, or any combination thereof. Example 38: An aerosol generating device according to any one of Examples 32 to 37, wherein the shielding layer is an edge layer, in particular an edge layer forming the second side of the composite cable. Example 39: An aerosol generating device according to any one of Examples 32 to 38, wherein the shielding layer has a layer thickness in the range of 0.3 mm to 3 mm, particularly 0.3 mm to 2 mm, or 0.25 mm to 5.5 mm, particularly 0.25 mm to 1.75 mm. Example 40: 40. The aerosol generating device according to any one of Examples 32 to 39, wherein the magnetic flux concentrator layer comprises a magnetic flux concentrator material. Example 41: 41. The aerosol generating device according to example 40, wherein the magnetic flux concentrator material is held in a substrate. Example 42: An aerosol generating device according to any one of Examples 32 to 41, wherein the magnetic flux concentrator layer, in particular the magnetic flux concentrator material of the magnetic flux concentrator layer, comprises at least one of a ferrimagnetic material, or a ferromagnetic material, or a mu metal, or a permalloy. Example 43: An aerosol generating device according to any one of Examples 32 to 42, wherein the magnetic flux concentrator layer, in particular the magnetic flux concentrator material of the magnetic flux concentrator layer, comprises a material having a maximum relative permeability of at least 1000, preferably at least 10,000, at a frequency of up to 50 kHz and a temperature of 25°C. Example 44: 44. The aerosol generating device according to any one of Examples 32 to 43, wherein the electrically insulating conductor casing layer does not contain a magnetic flux concentrator material. Example 45: An aerosol generating device according to any one of Examples 32 to 44, wherein the support layer is disposed on a side surface of the insulated conductor case layer when the composite cable is disposed around the cavity. Example 46: An aerosol generating device according to any one of Examples 32 to 45, wherein the magnetic flux concentrator layer is disposed on a side of the insulated conductor case layer facing outward, away from the cavity, when the composite cable is disposed around the cavity. Example 47: An aerosol generating device according to any one of Examples 32 to 46, wherein the shielding layer is disposed on a side of the insulated conductor case layer facing outward, away from the cavity, when the composite cable is disposed around the cavity. Example 48: An aerosol generating device according to any one of Examples 32 to 47, wherein the multilayer composite cable includes both a magnetic flux concentrator layer and a shielding layer, the magnetic flux concentrator layer being disposed on top of the electrically insulating conductor case layer, preferably on the side of the insulating conductor case layer facing outward away from the cavity, when the composite cable is disposed around the cavity, and the shielding layer being disposed on top of the magnetic flux concentrator layer, preferably an edge layer, in particular an edge layer forming the second side of the composite cable. Example 49: 49. An aerosol generating device according to any one of Examples 32 to 48, wherein the insulating conductor casing layer has a layer thickness in the range of 0.2 mm to 6 mm, in particular 0.4 mm to 2 mm, or 0.15 mm to 3 mm, in particular 0.3 mm to 1 mm, or 0.25 mm to 3 mm, in particular 0.3 mm to 1.5 mm, or 0.5 mm to 7 mm, in particular 0.7 mm to 4 mm, or 0.7 mm to 3 mm, or 0.4 mm to 9.2 mm, in particular 0.45 mm to 3.1 mm, or 0.4 mm to 7.2 mm, in particular 0.45 mm to 2.6 mm, or 0.45 mm to 3.7 mm, in particular 0.5 mm to 2.85 mm. Example 50: An aerosol generating device according to any one of Examples 32 to 49, wherein the portion of the insulating conductor case layer that embeds the conductor on the side opposite the first side has a thickness in the range of 0.2 mm to 7 mm, particularly 0.2 mm to 2 mm, or 0.25 mm to 1.5 mm, particularly 0.25 mm to 0.75 mm, or 0.2 mm to 5 mm, particularly 0.2 mm to 1.5 mm. Example 51: 10. An aerosol generating device according to any one of the preceding embodiments, wherein the conductor is fully embedded within the insulated conductor casing. Example 52: An aerosol generating device according to any one of the preceding embodiments, wherein the device comprises an induction module defining at least a portion of the cavity, and the induction coil is disposed on an inner surface of the induction module or on an outer surface of the sleeve-shaped induction module. Example 53: An aerosol generating device according to Example 52, wherein the guide module is a sleeve-shaped guide module, in particular a cylindrical guide module so as to define a cylindrical cavity. Example 54: An aerosol generating device according to any one of embodiments 52 or 53, wherein the induction module is arranged, in particular, removably arranged, within the device housing. Example 55: An aerosol generating device according to any one of the preceding embodiments, further comprising at least one susceptor at least partially disposed within the cavity. Example 56: 47. The aerosol generating apparatus according to example 46, wherein the susceptor is a tubular susceptor or a susceptor sleeve. Example 57: An aerosol-generating system according to any one of the preceding embodiments, comprising an aerosol-generating device according to any one of the preceding embodiments and an aerosol-generating article at least partially received or receivable within the cavity of the device, the aerosol-generating article including an aerosol-forming substrate that can be heated. Example 58: An aerosol generating system according to Example 57, comprising at least one susceptor positioned in thermal proximity or thermal contact with the aerosol-forming substrate such that, when the aerosol-generating article is received in the cavity of the device, the susceptor can be inductively heated by the induction heating arrangement during use.

[0098] The embodiments will now be further described with reference to the figures. [Brief explanation of the drawings]

[0099] [Figure 1] FIG. 1 shows a schematic longitudinal cross-sectional view of an aerosol generation system according to a first embodiment of the present invention. [Figure 2] FIG. 2 shows a schematic longitudinal cross-sectional view of an aerosol generation system according to a second embodiment of the present invention. [Figure 3] FIG. 3 shows a first embodiment of a guide module for use in the aerosol generation system according to FIG. [Figure 4] FIG. 4 shows a second embodiment of a directing module that can be used in an aerosol generating system according to the present invention. [Figure 5] FIG. 5 shows a third embodiment of a directing module that can be used in an aerosol generating system according to the present invention. [Figure 6] FIG. 6 shows a first embodiment of a composite cable for use in the aerosol generation system according to FIG. [Figure 7] FIG. 7 shows a second embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 8] FIG. 8 shows a third embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 9] FIG. 9 shows a fourth embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 10] FIG. 10 shows a fifth embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 11] FIG. 11 shows a sixth embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 12] FIG. 12 shows a seventh embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 13] FIG. 13 shows an eighth embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 14] FIG. 14 shows a ninth embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 15] FIG. 15 shows a tenth embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 16] FIG. 16 shows an eleventh embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 17] FIG. 17 shows a twelfth embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 18] FIG. 18 shows a thirteenth embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 19] FIG. 19 shows a fourteenth embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 20] FIG. 20 shows a fifteenth embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. [Figure 21] FIG. 21 shows a sixteenth embodiment of a composite cable that can be used in an aerosol generation system according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0100] 1 shows a schematic cross-sectional view of a first exemplary embodiment of an aerosol-generating system 1 according to the present invention. System 1 is configured for generating an aerosol by inductively heating an aerosol-forming substrate 97. System 1 comprises two main components: an aerosol-generating article 90 including the aerosol-forming substrate 97 to be heated, and an aerosol-generating device 10 for use with article 90. Device 10 comprises a cavity 20 for receiving article 90 and an induction heating arrangement 30 for heating the substrate 97 within article 90 when article 90 is received within cavity 20.

[0101] The article 90 has a rod shape similar to that of a conventional cigarette. In this embodiment, the article 90 comprises four elements arranged in a coaxial alignment: a substrate element 91, a support element 92, an aerosol cooling element 94, and a filter plug 95. The substrate element is disposed at the distal end of the article 90 and includes a heated aerosol-forming substrate. The aerosol-forming substrate 97 may comprise, for example, a crimped sheet of homogenized tobacco material containing glycerin as an aerosol former. The support element 92 comprises a hollow core forming a central air passage 93. The filter plug 95 functions as a mouthpiece and may comprise, for example, cellulose acetate fibers. All four elements are substantially cylindrical elements arranged consecutively one after the other. The four elements have substantially the same diameter and are surrounded by an outer wrapper 96 made of cigarette paper to form a cylindrical rod. The outer wrapper 96 may be wrapped around the aforementioned elements so that the free ends of the wrapper overlap each other. The wrapper may further include an adhesive that adheres the overlapping free ends of the wrapper to one another.

[0102] Device 10 comprises a substantially rod-shaped main body 11 formed by a substantially cylindrical device housing 19. Device 10 comprises, in a distal portion 13, a power source 16 (e.g., a lithium-ion battery) and electrical circuitry 17 including a controller for controlling the operation of device 10, particularly the heating process. In a proximal portion 14 opposite distal portion 13, device 10 comprises a cavity 20. Cavity 20 is open at the proximal end 12 of device 10, thereby allowing an item 90 to be inserted into cavity 20.

[0103] A cavity bottom portion 21 separates the distal portion 13 of the device 10 from the proximal portion 14, and in particular from the cavity 20. The bottom portion is preferably made of a thermally insulating material, such as PEEK (polyetheretherketone). Thus, electrical components within the distal portion 13 can be kept isolated from aerosols or residues generated by the aerosol-generating process within the cavity 20.

[0104] The induction heating arrangement 30 includes an induction coil 31 for generating an alternating magnetic field, particularly a high-frequency magnetic field, within the cavity 20. The high-frequency magnetic field may preferably be in the range of 500 kHz (kilohertz) to 30 MHz (megahertz), particularly 5 MHz (megahertz) to 15 MHz (megahertz), and preferably 5 MHz (megahertz) to 10 MHz (megahertz). In this embodiment, the induction coil 31 is a helical coil that circumferentially surrounds the cylindrical cavity 20 along its length axis. The induction coil 31 is formed by multiple turns of a composite cable 32 that includes multi-wire conductors 33. Details of the composite cable 32 are described further below, particularly with reference to Figures 3-18.

[0105] The induction heating arrangement 30 further includes a susceptor 60 disposed within the cavity 20 so as to experience the magnetic field generated by the induction coil 31. In this embodiment, the susceptor 60 is a susceptor blade 61. At its distal end 64, the susceptor blade is disposed in the bottom portion 21 of the cavity 20 of the apparatus. From there, the susceptor blade 61 extends into the interior void of the cavity 20 toward an opening of the cavity 20 at the proximal end 12 of the apparatus 10. The other end, i.e., the distal free end 63, of the susceptor blade 60 is tapered to allow the susceptor blade to easily penetrate an aerosol-forming substrate 97 within the distal end portion of the article 90.

[0106] Alternatively, as shown in Figure 2, the susceptor 60 may be part of an aerosol-generating article 90. In this figure, the susceptor 99 is a susceptor strip made of a susceptible material embedded within the aerosol-forming substrate 97 of the article 90. The susceptor strip 99 is disposed so as to extend the length of the center of the substantially cylindrical article 90. Otherwise, the embodiment of the aerosol-generating system according to Figure 2 is identical to the embodiment of the aerosol-generating system according to Figure 1. Accordingly, identical or similar features are designated with the same reference numerals.

[0107] With reference to both embodiments, the induction heating process is as follows: When the apparatus 10 is operated, a high-frequency alternating current is passed through the induction coil 31. Because the coil is disposed around the cavity 20, the alternating current through the coil induces an alternating magnetic field within the cavity 20. Depending on the magnetic and electrical properties of the respective susceptor materials, the alternating magnetic field induces at least one of eddy currents or hysteresis losses within the susceptor blades 61 or susceptor strips 99, respectively. As a result, the susceptor blades 61 or susceptor strips 99, respectively, are heated to a temperature sufficient to form an aerosol from the substrate 97 in thermal proximity or direct physical contact. The generated aerosol is drawn downstream through the aerosol-generating article 90 and can be inhaled by a user.

[0108] 1 and 2, induction coil 31 is part of induction module 40 that is disposed with proximal portion 14 of aerosol generation device 10. Induction module 40 has a substantially cylindrical shape that is coaxially aligned with central longitudinal axis 71 of rod-shaped device 10. As can be seen in FIG. 1, induction module 40 forms at least a portion of cavity 20 or at least a portion of the interior surface of cavity 20.

[0109] FIG. 3 shows induction module 40 in more detail. In addition to induction coil 31, induction module 40 includes a tubular support sleeve 42 that carries helically wound, cylindrical induction coil 31. Tubular support sleeve 42 includes an annular recess 41 on its inner surface in which cylindrical induction coil 31 is received. Thus, both end portions 44 of support sleeve 42 project radially inward toward central axis 71 to hold induction coil 31 in place within the recess of support sleeve 42. Support sleeve 42 may be made of any suitable material, such as plastic. In particular, support sleeve 42 may form at least a portion of cavity 20, i.e., at least a portion of the inner surface of cavity 20.

[0110] 4 illustrates a second embodiment of an induction module 40. In the figure, a tubular support sleeve 42 includes an annular recess 43 in its outer surface for receiving a cylindrical induction coil 31 therein. Thus, both end portions 44 of the support sleeve 42 project radially outward, away from the central axis 71, to hold the induction coil 31 in place within the recess 43.

[0111] 5 shows a third embodiment of the induction module 40. The induction module 40 is almost identical to the module according to FIG. 4. Furthermore, the induction module 40 of the third embodiment includes a susceptor sleeve surrounded by an induction coil 32. 69 That is, the susceptor sleeve 69 is part of the aerosol-generating device but not part of the aerosol-generating article. The susceptor sleeve 69 is disposed within the annular recess 45 in the inner surface of the support sleeve. Thus, the susceptor sleeve 69 forms at least a portion of the inner surface of the cavity 20. Thus, when the article is inserted into the cavity, the susceptor sleeve 69 surrounds the substrate element 91 to heat the aerosol-forming substrate from the outside. In this configuration, the susceptor sleeve 69 acts as an oven heater. This is in contrast to the embodiments shown in FIGS. 1 and 2, in which the susceptor blades 61 or susceptor strips 99, respectively, heat the aerosol-forming substrate from the inside.

[0112] FIG. 6 shows a composite cable 32 used to form the induction coil 31 of the device 10 shown in more detail in FIGS. 1 and 2. The composite cable 32 includes a conductor 33 for carrying the current used to generate the magnetic field. The conductor 33 is completely embedded in an insulated conductor case 34 to electrically insulate adjacent turns of the induction coil from each other and therefore prevent short circuits. In accordance with the present invention, the conductor 33 includes a plurality of uninsulated wires 35 in electrical contact with each other. In this embodiment, the conductor 33 includes a total of 22 wires 35 arranged in two layers on top of each other, with each layer including 11 wires 35. The layers are aligned so that the wires 35 of one layer are disposed in grooves formed between adjacent wires 35 of the other layer. Thus, the assembly of all the wires 35 forms the conductor 33 having a substantially trapezoidal cross section.

[0113] Each wire 35 may have a diameter in the range of 0.25 mm to 0.75 mm, e.g., 0.5 mm. Accordingly, the width dimension 33.1 of the conductor 33 is given by 11.5 times the wire diameter. That is, the width dimension 33.1 of the conductor 33 may be in the range of 2.875 mm to 8.625 mm, e.g., 5.75 mm. Similarly, the thickness dimension 33.2 of the conductor 33 is given by approximately 1.73 times the wire diameter. That is, the width dimension 33.1 of the conductor 33 may be in the range of approximately 0.4 mm to approximately 1.3 mm, e.g., approximately 6.5 mm. In this embodiment, the width dimension of the conductor 33 corresponds to the maximum dimension of the conductor's cross section perpendicular to the radial direction 70 of the multiple turns of the composite cable (see the dashed and dotted arrows in Figures 4-6). Similarly, the thickness dimension of the conductor 33 corresponds to the maximum dimension of the conductor's cross section in the radial direction 70 of the multiple turns of the composite cable 32 (see the dashed and dotted arrows in Figures 4-6). The width dimension 33.1 of the conductor 33 is much greater than its thickness dimension 33.2, so the conductor 33 can be viewed as a flat conductor 33.

[0114] The same is true for the entire cable 32, which has a width dimension 32.1 that is much larger than its thickness dimension 32.2. Therefore, the composite cable 32 may be referred to as a flat composite cable 32. In this embodiment, the width dimension 32.1 of the composite cable 32, i.e., the thickness dimension 32.2 of the composite cable 32, is 32 The maximum cross-sectional dimension of the composite cable 32 perpendicular to the radial direction 70 of the multiple turns of the composite cable (see dash-dotted arrows in Figures 4-6) may be in the range of 1 mm to 7 mm, particularly 1.5 mm to 5 mm. Similarly, the thickness dimension 32.2 of the composite cable 32, i.e., the maximum cross-sectional dimension of the composite cable 32 in the radial direction 70 of the multiple turns of the composite cable (see dash-dotted arrows in Figures 4-6), may be in the range of 0.5 mm to 9 mm, particularly 0.7 mm to 9 mm, preferably 0.9 mm to 5 mm. The outer cross-section of the composite cable 32 is substantially rectangular with rounded edges.

[0115] When disposed about cavity 20, composite cable 32 includes a first side 38 that faces inwardly toward cavity 20 and a second side 39 opposite the first side that faces outwardly away from cavity 20. This is shown in Figure 6, which shows a section of the composite cable in a wound configuration.

[0116] As can be further seen in FIG. 6 , the conductors 33 are disposed substantially symmetrically about a first axis of symmetry 32.3 of the outer cross section of the cable 32, which extends between the first side surface 38 and the second side surface 39 in the radial direction 70. In contrast, the conductors 33 are disposed asymmetrically about a second axis of symmetry 32.4 of the outer cross section of the composite cable 32, such that the conductors 33 are closer to the first side surface 38 of the composite cable than to the second side surface 39. That is, the insulated conductor casing 34 is primarily positioned toward the second side surface 39 of the composite cable and therefore further radially outward than the conductors 33. In particular, the conductors 33 are disposed between the first side surface 38 and the second axis of symmetry. Thus, the insulated conductor casing 34 can act as a protective sheath surrounding the conductors 33 when the composite cable 32 is disposed around a cavity. The minimum distance 33.8 between the conductor 33 and the first side surface 38 is at most 0.1 mm to 0.5 mm, in particular in the range of 0.1 mm to 0.3 mm.

[0117] Additionally, the insulating conductor casing 34 may serve other purposes. In this embodiment, the insulating conductor casing 34 includes a magnetic flux concentrator material to focus or concentrate the magnetic field within the cavity 20. Advantageously, this increases the level of heat generated in the susceptor for a given level of power passing through the induction coil 31, compared to an induction coil without a magnetic flux concentrator. Therefore, the efficiency of the aerosol generation device 10 is improved. Furthermore, by distorting the magnetic field toward the cavity, the magnetic flux concentrator material of the insulating conductor casing 34 reduces the extent to which the magnetic field propagates beyond the induction coil 31. That is, the magnetic flux concentrator material of the insulating conductor casing 34 acts as a magnetic shield. Advantageously, this may reduce undesired magnetic field interference with other sensitive components of the aerosol generation device 10, for example, those having a metal outer housing or having sensitive external components in close proximity to the device 10. Notably, incorporating the magnetic flux concentrator material into the composite cable 32 allows for both the induction coil 31 and a suitable magnetic flux concentrator to be provided in a single component. Advantageously, this reduces the effort required to manufacture the aerosol generating device 10, both in terms of cost and time. By way of example, the insulated conductor casing 34 may include or be made from laminations, pure ferrite, or a proprietary iron- or ferrite-based composition. Here, the insulated conductor casing 34 is made from Alphaform MF, available from Fluxtrol Inc., 1388 Atlantic Blvd., Auburn Hills, MI 48326, USA. Alphaform MF is a formable, soft magnetic composite developed based on magnetic particles with a thermosetting epoxy binder suitable for frequencies between 10 kilohertz and 1000 kilohertz.

[0118] Advantageously, the wires 35 of the conductor 33 are embedded in the material of the insulating conductor casing 34 by extrusion or lamination.

[0119] FIG. 7 shows a second embodiment of a composite cable 32 that is very similar to the first embodiment of the composite cable 32 shown in FIG. 6 . Accordingly, identical or similar features are designated by the same reference numerals. In contrast to the first embodiment, the composite cable 32 according to FIG. 7 includes a conductor 33 consisting of a single layer of seven wires 35. Each of the seven wires 35 has a larger diameter than the wires 35 shown in FIG. 6 . The diameters are selected so that the cross-sectional area of ​​the conductor 33 in FIG. 7, i.e., the sum of the cross-sectional areas of all seven wires 35, substantially corresponds to the cross-sectional area of ​​the conductor 33 in FIG. 6, i.e., the sum of the cross-sectional areas of all twenty-two wires 35. Therefore, the composite cable 32 shown in FIG. 6 and the composite cable 32 shown in FIG. 7 have substantially the same electrical properties, in particular, substantially the same electrical resistance. However, the composite cable 32 according to FIG. 6 is more flexible due to the larger number of wires 35 and the smaller diameter.

[0120] 8-10 show three further embodiments of a composite cable 132. In all three embodiments, the composite cable 132 is realized as a multi-layer composite cable 132 including an electrically insulating conductor casing layer 134 forming an insulating conductor casing, as described above, plus a support layer 136. Both layers 134, 136 completely encapsulate the conductor 133. Advantageously, the different layers may be attached to each other by a lamination process.

[0121] The support layer 136 functions to increase the mechanical resistance of the composite cable 134. The support layer 136 is electromagnetically inert in all three embodiments so as not to affect the inducibility of the magnetic field generated by the current passing through the electrical conductors 132. For example, the support layer 136 may be made from polyetheretherketone or polyaryletherketone, both of which are electromagnetically inert materials.

[0122] In all three embodiments, each support layer 136 is an edge layer, and in particular, an edge layer that forms a first side 138 of the composite cable 132 .

[0123] In the embodiment shown in Figures 8 and 9, the conductors 133 are at least partially embedded in respective support layers 136 and partially embedded in insulated conductor encasement layers 134. Except for the partial embedding in the support layers 136 and insulated conductor encasement layers, the composite cable 132 shown in Figures 8 and 9 is very similar to the composite cable 32 shown in Figures 6 and 7, respectively. Accordingly, identical or similar features are designated with the same reference numerals, but incremented by 100.

[0124] In contrast, in the embodiment shown in FIG. 10 , the conductors 133 are not embedded in the support layer 136. Instead, the support layer 136 covers the side of the conductors 133 facing inward toward the cavity 20 when the composite cable 132 is disposed around the cavity 20. Thus, the support layer 136 is thinner than the support layer 136 of FIGS. 8 and 9 . In further contrast to the embodiments shown in FIGS. 8 and 9 , the insulating conductor encasement layer 134 of the cable 132 shown in FIG. 10 consists of three portions: a first portion 134.1 disposed on the side of the conductors 133 opposite the first side 138, and second and third portions 134.2 and 134.3 disposed transversely to the narrow side of the flat conductors 133. Furthermore, the composite cable 132 according to FIG. 10 has sharp edges rather than rounded edges.

[0125] 8 and 9, the support layer 136 may have a layer thickness in the range of 0.1 mm to 1 mm, in particular 0.2 mm to 0.5 mm. Similarly, in the embodiment according to Fig. 10, the support layer 136 may have a layer thickness in the range of 0.25 mm to 1 mm, in particular 0.25 mm to 0.5 mm.

[0126] The insulating conductor encasement layer 134 may have a total layer thickness in the range of 0.5 mm to 7 mm, in particular 0.7 mm to 4 mm, or 0.7 mm to 3 mm, or 0.4 mm to 7.2 mm, in particular 0.45 mm to 2.6 mm. Similarly, the portion of the insulating conductor encasement layer 134 that embeds the conductors on the side opposite the first side, in particular the first portion 134.1, may have a thickness in the range of 0.2 mm to 5 mm, in particular 0.2 mm to 1.5 mm.

[0127] FIGS. 11-13 illustrate three additional embodiments of a composite cable 232 similar to the embodiment shown in FIGS. 8-10. Accordingly, identical or similar features are designated by the same reference numerals, but incremented by 100. In contrast to the embodiment shown in FIGS. 8-10, the composite cable 232 shown in FIGS. 11-13 additionally includes a shielding layer 237 disposed on top of the insulating conductor casing layer 234, opposite the support layer 236. The shielding layer 237 primarily functions to reduce the adverse effects of magnetic fields in the region outside the shielding layer 237 and, conversely, to reduce distortion of the magnetic field by conductive or highly magnetically susceptible materials in the immediate vicinity of the device or in the housing of the device itself. Therefore, the shielding layer 237 preferably includes a conductive material, such as a metal coating, applied to the side of the insulating conductor casing layer facing outward, away from the cavity. As can be further seen from FIGS. 11-13, each shielding layer 237 is an edge layer that forms the second side 239 of the multilayer composite cable 232.

[0128] The shielding layer 237 may have a layer thickness in the range of 0.3 mm to 3 mm, particularly 0.3 mm to 2 mm.

[0129] To compensate for the additional layer 237, the layer thickness of the insulating conductor encasement layer 234 in the embodiment shown in Figures 11-13 may be different from the respective layer thicknesses in the embodiment shown in Figures 8-10. Thus, the insulating conductor encasement layer in the embodiment shown in Figures 11-13 may have a total layer thickness in the range of 0.2 millimeters to 6 millimeters, particularly 0.4 millimeters to 2 millimeters, or in the range of 0.4 millimeters to 9.2 millimeters, particularly 0.45 millimeters to 3.1 millimeters. Similarly, the portion of the insulating conductor encasement layer 234 that embeds the conductors on the side opposite the first side, particularly first portion 234.1, may have a thickness in the range of 0.2 millimeters to 7 millimeters, particularly 0.2 millimeters to 2 millimeters.

[0130] FIGS. 14-16 illustrate three additional embodiments of a composite cable 332 similar to the embodiment shown in FIGS. 11-13. Accordingly, identical or similar features are designated by the same reference numerals, but incremented by 100. In contrast to the embodiment shown in FIGS. 11-13, the composite cable 332 shown in FIGS. 14-16 includes a magnetic flux concentrator layer 337 instead of a shielding layer. For example, the magnetic flux concentrator layer 337 may include a ferrite material. The ferrite material acts as a magnetic flux concentrator material. Furthermore, the layer thicknesses are slightly different from those of the embodiments shown in FIGS. 11-13. The insulating conductor casing layer 334 of the embodiments shown in FIGS. 14-16 may have a total layer thickness ranging from 0.15 mm to 3 mm, particularly 0.3 mm to 1 mm, or from 0.45 mm to 3.7 mm, particularly 0.5 mm to 2.85 mm. Similarly, the portion of insulating conductor casing layer 334 that encapsulates the conductor on the side opposite the first side, particularly first portion 334.1, may have a thickness in the range of 0.25 mm to 1.5 mm, particularly 0.25 mm to 0.75 mm. Magnetic flux concentrator layer 337 may have a layer thickness in the range of 0.25 mm to 5.5 mm, particularly 0.25 mm to 1.75 mm.

[0131] As shown in Figure 17, composite cable 432 may not include a support layer, but may include only shield layer 437 and insulating conductor encasement layer 434 in which conductor 433 is embedded. Alternatively, as shown in Figure 18, composite cable 532 may include only flux concentrator layer 537 and insulating conductor encasement layer 534 in which conductor 533 is embedded, but may not include a support layer. In this configuration,

[0132] As shown in FIG. 19, composite cable 632 may also include a cross-section other than the substantially rectangular cross-section shown in FIGS. 1-18. In this embodiment, composite cable 632 has an arc-shaped cross-section. Cable 632 is also a multi-layer composite cable including a shielding or magnetic flux concentrator layer 637 and an insulated conductor encasement layer 634 in which a substantially arc-shaped conductor 633 is embedded. With respect to the arc-shaped cross-section, the width dimension of the composite may vary along a first side 638, or along a second side 639, or between the first side 638 and the second side 639. 639 The first side parallel to 638 The thickness dimension is measured along a centerline between the first side 638 and the second side 639. Similarly, the thickness dimension may be measured radially along an axis perpendicular to the first side 638 and the second side 639.

[0133] Figure 20 shows another embodiment of a multi-layer composite cable 732 that is a combination of the composite cables according to Figures 11 and 14. Multi-layer composite cable 732 includes a support layer 736, an insulating conductor encasement layer 734 on top of support layer 736 in which conductors 733 are embedded, a magnetic flux concentrator layer 737 on insulating conductor encasement layer 734, and a shielding layer 770 disposed on top of magnetic flux concentrator layer 737 opposite support layer 736. Shielding layer 770 may be, for example, a metal coating on top of magnetic flux concentrator layer 737.

[0134] As shown in Figure 21, it is also possible to omit the support layer, as in Figures 17 and 18. Thus, Figure 21 shows yet another embodiment of a multi-layer composite cable 832, which is a combination of the composite cables according to Figures 17 and 18. Multi-layer composite cable 832 includes conductors 833 embedded in an insulating conductor encasement layer 834, a magnetic flux concentrator layer 837 on top of insulating conductor encasement layer 834, and a shielding layer 870 disposed on top of magnetic flux concentrator layer 837.

[0135] 14-16, 18 and 20-21, each insulating conductor casing layer 334, 535, 734, 834 preferably does not include magnetic flux concentrator material due to the presence of each additional magnetic flux concentrator layer 337, 537, 737, 837. However, each insulating conductor casing layer 334, 535, 734, 834 may also include magnetic flux concentrator material in addition to each magnetic flux concentrator layer 337, 537, 737, 837.

[0136] For purposes of this specification and the appended claims, unless otherwise indicated, all numbers expressing amounts, quantities, percentages, and the like are to be understood in all instances as modified by the term "about." Also, all ranges include the maximum and minimum points disclosed, including any intermediate ranges therebetween, which may or may not be specifically recited herein. Thus, in this context, the number A is to be understood as A ± 5 percent.

Claims

1. 1. An aerosol generating apparatus for generating an aerosol by inductive heating of an aerosol-forming substrate, said apparatus comprising: a device housing including a cavity configured to removably receive at least a portion of the aerosol-forming substrate to be heated; an induction heating arrangement including an induction coil for generating an alternating magnetic field in the range of 500 kHz to 30 MHz within the cavity, the induction coil being formed by multiple turns of a composite cable disposed around at least a portion of the cavity, the composite cable including an electrical conductor at least partially embedded in an insulated conductor case, the electrical conductor including a plurality of uninsulated wires in electrical contact with each other; An aerosol generating device, wherein the composite cable arranged around the cavity includes a first side facing inward toward the cavity and a second side opposite the first side facing outward away from the cavity, and the conductor is arranged radially asymmetrically with respect to the outer cross section of the composite cable so as to be closer to the first side than to the second side of the composite cable.

2. 2. The aerosol generating device of claim 1, wherein the wires extend parallel to each other along the length of the composite cable in a single layer, or the wires extend parallel to each other along the length of the composite cable in multiple layers on top of each other.

3. 3. The aerosol generating device according to claim 2, wherein the single layer or each of the plurality of layers is a flat layer, or the single layer or each of the plurality of layers is a curved layer.

4. 4. An aerosol generating device according to claim 1, wherein the composite cable has a substantially circular outer cross-section, or a substantially non-circular outer cross-section, in particular a substantially rectangular outer cross-section, or a substantially square outer cross-section, or a substantially elliptical outer cross-section, or a substantially oval outer cross-section, or a substantially parallelogram-shaped outer cross-section, or a substantially trapezoidal outer cross-section, or a substantially arc-shaped outer cross-section.

5. 5. An aerosol generating device according to claim 1, wherein the composite cable is a flat cable and / or the conductor is a flat conductor.

6. An aerosol generating device according to any one of claims 1 to 5, wherein the conductor has a substantially rectangular outer cross-section, or a substantially square outer cross-section, or a substantially elliptical outer cross-section, or a substantially oval outer cross-section, or a substantially parallelogram-shaped outer cross-section, or a substantially trapezoidal outer cross-section, or a substantially arc-shaped outer cross-section.

7. 7. An aerosol generating device according to any one of claims 1 to 6, wherein the insulated conductor case comprises a magnetic flux concentrator material, in particular a material having a maximum relative magnetic permeability of at least 1000, preferably at least 10,000, at a frequency of up to 50 kHz and a temperature of 25°C.

8. 8. The aerosol generating device according to claim 1, wherein the composite cable is a multi-layer composite cable including an electrically insulating conductor case layer that forms the insulating conductor case, and further including at least one of a support layer, a magnetic flux concentrator layer, or a shielding layer.

9. 9. The aerosol generating device according to claim 8, wherein the support layer comprises an electromagnetically inert material, in particular at least one of polyetheretherketone or polyaryletherketone.

10. 10. An aerosol generating device according to claim 8 or 9, wherein the support layer is an edge layer, in particular an edge layer forming the first side of the composite cable, and one of the magnetic flux concentrator layer or the shielding layer is an edge layer, in particular an edge layer forming the second side of the composite cable.

11. An aerosol generating device according to any one of claims 8 to 10, wherein the shielding layer comprises at least one of a conductive material, in particular aluminum, copper, tin, steel, gold, silver, a conductive polymer, ferrite, or any combination thereof.

12. 12. The aerosol generating device according to claim 1, further comprising at least one susceptor disposed at least partially within the cavity.

13. 13. An aerosol generation system comprising an aerosol generating device according to any one of claims 1 to 12 and an aerosol-generating article at least partially received or receivable in the cavity of the device, wherein the aerosol-generating article comprises the aerosol-forming substrate to be heated.

14. 14. The aerosol generating system of claim 13, wherein the aerosol-generating article comprises at least one susceptor positioned in thermal proximity or thermal contact with the aerosol-forming substrate such that, in use, the susceptor can be inductively heated by the induction heating arrangement when the article is received in the cavity of the device.

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