Aerosol-generating device with sensing assembly comprising shield plate

Abstract

The present invention relates to an aerosol-generating device comprising a chamber for receiving an aerosol-forming substrate and a sensing assembly for detecting the aerosol-forming substrate in the chamber. The sensing assembly includes an emitter configured to emit electromagnetic radiation into the cavity, a sensor configured to measure the received electromagnetic radiation at a wavelength, and a shield plate configured to block the electromagnetic radiation and positioned outside the cavity such that the sensor is disposed between the cavity and at least a portion of the shield plate. The shield plate includes a U-shaped section, a planar first portion connected to a first end edge of the U-shaped section, and a planar second portion connected to a second end edge of the U-shaped section. The first portion and the second portion of the shield plate are non-coplanar.

Description

Technical Field

[0001] The present invention relates to an aerosol generating device and also to an aerosol generating system. Background Art

[0002] It is known to provide an aerosol generating device for generating an inhalable vapor. Such a device may heat an aerosol-forming substrate to a temperature at which one or more components of the aerosol-forming substrate volatilize without burning the aerosol-forming substrate. The aerosol-forming substrate may be provided as part of an aerosol-generating article. The aerosol-generating article may have a strip shape for inserting the aerosol-generating article into a cavity (such as a heating chamber) of the aerosol-generating device. The heating assembly may be arranged in or around the heating chamber so as to heat the aerosol-forming substrate once the aerosol-generating article is inserted into the heating chamber of the aerosol-generating device.

[0003] Aerosol generating devices typically include several electronic components for enabling different functions of the device. Due to heat conduction away from the thermal heating chamber during use, the temperature of such electronic components may rise to unfavorably high temperatures. This may be particularly serious for electronic components that need to be located very close to the heating chamber and cannot tolerate very high temperatures. For example, optical components may be positioned near the opening of the heating chamber to identify the insertion of an aerosol generating article into the heating chamber. At the same time, electronic components like optical components may not generally operate at excessively high temperatures.

[0004] It would therefore be desirable to provide an aerosol generating device which reduces the temperature rise of electronic components during use.It would be desirable to provide an aerosol generating device with improved heat dissipation. Summary of the invention

[0005] According to an embodiment of the present invention, an aerosol generating device is provided. The aerosol generating device may include a cavity for receiving an aerosol-forming substrate. The aerosol generating device may include a sensing component for detecting the aerosol-forming substrate in the cavity. The sensing component may include an emitter configured to emit electromagnetic radiation into the cavity. The sensing component may include a sensor configured to measure a wavelength of received electromagnetic radiation. The sensing component may include a shielding plate configured to block electromagnetic radiation. The shielding plate may be positioned outside the cavity so that the sensor is arranged between the cavity and at least a portion of the shielding plate. The shielding plate may include a U-shaped section. The shielding plate may include a planar first portion. The planar first portion may be connected to a first end edge of the U-shaped section. The shielding plate may include a planar second portion. The planar second portion may be connected to a second end edge of the U-shaped section. The first portion and the second portion of the shielding plate may be non-coplanar.

[0006] According to an embodiment of the present invention, an aerosol generating device is provided. The aerosol generating device includes a cavity for receiving an aerosol-forming substrate. The aerosol generating device includes a sensing component for detecting the aerosol-forming substrate in the cavity. The sensing component includes an emitter configured to emit electromagnetic radiation into the cavity. The sensing component includes a sensor configured to measure the received electromagnetic radiation of a wavelength. The sensing component includes a shielding plate configured to block electromagnetic radiation. The shielding plate is positioned outside the cavity so that the sensor is arranged between the cavity and at least a portion of the shielding plate. The shielding plate includes a U-shaped section. The shielding plate includes a planar first portion. The planar first portion is connected to a first end edge of the U-shaped section. The shielding plate includes a planar second portion. The planar second portion is connected to a second end edge of the U-shaped section. The first portion and the second portion of the shielding plate are non-coplanar.

[0007] By means of the shielding plate of the present invention, an aerosol generating device with reduced temperature rise of electronic components during use can be provided. By means of the shielding plate of the present invention, an aerosol generating device with improved heat dissipation can be provided.

[0008] An aerosol generating device including a sensing component may advantageously be capable of detecting the presence and type of an aerosol generating substrate at least partially received in a cavity based on a measurement of the received electromagnetic radiation of at least one wavelength obtained by a sensor. The aerosol forming substrate may be included in an aerosol generating article at least partially received in the cavity. In use, the transmitter may advantageously emit electromagnetic radiation into a cavity in which the aerosol forming substrate is at least partially received. The electromagnetic radiation incident on the aerosol forming substrate or the aerosol generating article may undergo one of the following: absorption, reflection or transmission. The amount of absorption, reflection or transmission of the electromagnetic radiation at different wavelengths may depend on the chemical structure of the aerosol forming substrate or article. Therefore, the chemical structure of the aerosol forming substrate or article may affect the electromagnetic radiation received by the sensor from the cavity. Different aerosol forming substrates or articles may have different chemical structures and therefore may affect the electromagnetic radiation differently. Therefore, measuring the received electromagnetic radiation may advantageously be used to determine the presence and type of the aerosol forming substrate received in the cavity.

[0009] Preferably, the sensor is configured to measure the intensity of electromagnetic radiation of at least one wavelength.The measuring may comprise comparing the intensity of electromagnetic radiation of at least one wavelength to a threshold value.

[0010] By means of the shielding plate of the present invention, the temperature rise of the sensing component during use can be reduced by means of the heat dissipation function of the shielding plate.

[0011] The cavity of the aerosol generating device may comprise an opening at a first end through which an aerosol-forming substrate may be received. The cavity may be configured to receive the aerosol-forming substrate along a longitudinal axis of the cavity. The longitudinal axis of the cavity may be parallel to the longitudinal axis of the aerosol generating device.

[0012] The emitter and the sensor may be positioned at substantially the same height relative to the longitudinal axis of the cavity. In other words, the emitter and the sensor may be positioned in a plane substantially perpendicular to the longitudinal axis of the cavity. The emitter and the sensor may be positioned such that the electromagnetic radiation beam travels from the emitter to the sensor in a direction substantially perpendicular to the longitudinal axis of the cavity.

[0013] The cavity may include a second end opposite the first end. The second end may include a base of the cavity.

[0014] The transmitter and sensor may be positioned to transmit electromagnetic radiation to and receive electromagnetic radiation from the cavity at a region between the first end and the second end of the cavity. The transmitter may be positioned outside the cavity. The sensor may be positioned outside the cavity.

[0015] The transmitter and sensor may be positioned distally of the second end of the cavity along the longitudinal axis of the cavity.The transmitter and sensor may be positioned so as to transmit electromagnetic radiation to and receive electromagnetic radiation from the second end of the cavity, respectively.

[0016] The position of the shielding plate may advantageously mean that electromagnetic radiation external to the aerosol generating device is blocked by the shielding plate. This may mean that electromagnetic radiation external to the aerosol generating device is prevented from reaching the sensor. Otherwise, external electromagnetic radiation may be received by the sensor and therefore picked up as noise. Therefore, the shielding plate may advantageously improve the accuracy of the sensing assembly by reducing noise. This may improve the signal-to-noise ratio of the sensor measurement.

[0017] One source of external electromagnetic radiation may be from the user of the aerosol generating device. For example, the user's hand may produce parasitic capacitance effects in the order of picofarads, which may be detected as noise by the sensor in the absence of a shield.

[0018] As used herein, a shield "blocks" electromagnetic radiation may mean that the shield prevents external electromagnetic radiation from passing through and reaching the sensor. The shield can reduce the intensity of externally generated electromagnetic radiation at the sensor by at least 90%, preferably by at least 95%, and even more preferably by at least 99%. The shield can effectively reduce the intensity of electromagnetic radiation between the infrared range and the ultraviolet range. Preferably, the shield can effectively reduce the intensity of electromagnetic radiation with a wavelength between 1 nanometer and 100,000 nanometers, preferably between 200 nanometers and 30,000 nanometers, and even more preferably between 200 nanometers and 15,000 nanometers. The shield can reduce the intensity of externally generated electromagnetic radiation by absorbing or reflecting radiation.

[0019] The shielding plate may include a conductive material. The shielding plate may be made of a conductive material. The conductive material may have a 6 Siemens / meter, preferably at least 1×10 7 Siemens / meter, even more preferably at least 5×10 7 Conductivity in Siemens / meter.

[0020] The shielding plate may comprise a thermally conductive material. The shielding plate may be formed from a thermally conductive material. This may be particularly advantageous when the aerosol generating device further comprises a heater assembly configured to heat an aerosol-forming substrate received in the cavity during use. The shielding plate comprising a thermally conductive material may advantageously dissipate heat generated by the heater assembly away from the sensor. The sensor may be particularly sensitive to heating and may be damaged by excessive heating. The shielding plate comprising a thermally conductive material may advantageously prevent the sensor from overheating during use of the aerosol generating device. The shielding plate may be configured to prevent the temperature of the sensor from exceeding 115 degrees Celsius during use of the aerosol generating device.

[0021] The thermally conductive material may have a thermal conductivity of at least 10 Watts / meter-Kelvin, preferably at least 80 Watts / meter-Kelvin, preferably at least 100 Watts / meter-Kelvin, even more preferably at least 150 Watts / meter-Kelvin.

[0022] The shielding plate may include a metal or an alloy. The shielding plate may include at least one of aluminum and stainless steel.

[0023] The shielding plate may comprise phosphor bronze, preferably nickel-plated phosphor bronze. The shielding plate may be made of phosphor bronze, preferably nickel-plated phosphor bronze. The shielding plate may be made of phosphor bronze, preferably nickel-plated phosphor bronze.

[0024] The shielding plate may have a thickness between 0.1 mm and 3 mm. Preferably, the shielding plate has a thickness of 0.2 mm. This thickness may advantageously be high enough to ensure that the shielding plate adequately blocks external electromagnetic radiation.

[0025] The size and position of the shielding plate can be designed so that the emitter is between the shielding plate and the cavity. This can advantageously ensure that external electromagnetic radiation does not enter the cavity through the emitter. The shielding plate can also advantageously dissipate heat away from the emitter.

[0026] The shielding plate may have a width between 1 mm and 10 mm, more preferably between 2 mm and 4 mm, even more preferably about 3 mm. The shielding plate may have a length between 10 and 30 mm, more preferably between 15 and 25 mm, even more preferably about 22 mm.

[0027] The emitter and sensor may be parallel to each other. In other words, the angle between the emitter and the sensor may be about 0 degrees.

[0028] When referring to the angle between the emitter and the sensor herein, the angle is defined between the central optical axis of the emitter and the central optical axis of the sensor. This may be the same as the angle defined between the surface of the aerosol-forming substrate or article at least partially received in the cavity and the emitter and the sensor.

[0029] The emitter and the sensor may be adjacent to each other. In this way, the emitter and the sensor may advantageously be arranged on the same chip. This may advantageously reduce the complexity of the sensing component.

[0030] The transmitter may be positioned on top of the sensor.The sensing assembly may include the transmitter between the shield and the sensor.

[0031] Alternatively, the sensor and the emitter may not be parallel. The angle between the sensor and the emitter may be between 20 and 120 degrees, preferably between 60 and 100 degrees, even more preferably between 70 and 90 degrees. Most preferably, the angle between the sensor and the emitter may be about 80 degrees. This angle may be particularly advantageous when the aerosol-forming substrate is contained in a strip-shaped aerosol-generating article and the electromagnetic radiation is incident on the article perpendicular to the cylindrical axis of the strip.

[0032] When the sensor and the emitter are not parallel, the angle between the normal to the plane of the first part and the normal to the plane of the second part may be substantially the same as the angle between the sensor and the emitter. In other words, the angle between the normal to the plane of the first part and the normal to the plane of the second part may be between 20 and 120 degrees, preferably between 60 and 100 degrees, even more preferably between 70 and 90 degrees. Most preferably, the angle may be about 80 degrees.

[0033] The sensing assembly may also include a substrate. The substrate may include a first side to which at least one of the transmitter and the sensor is attached. Both the transmitter and the sensor may be attached to the first side. The substrate may include a second side opposite the first side to which the shielding plate is attached. This may advantageously be a simple arrangement that is easy to manufacture. The substrate may include one or more printed circuit boards (PCBs). The substrate may be a printed circuit board (PCB). The substrate may include more than one PCB. The substrate may include or consist of one or more flexible PCBs.

[0034] The substrate may comprise a flexible portion. The flexible portion may be configured such that the emitter is movable relative to the sensor by bending the flexible portion. As described above, the angle between the emitter and the sensor may preferably be between 20 and 120 degrees, preferably between 60 and 100 degrees, and even more preferably between 70 and 90 degrees. Most preferably, the angle between the sensor and the emitter may be about 80 degrees. A substrate comprising a flexible portion may advantageously allow the angle between the emitter and the sensor to be controlled in a simple manner during the manufacturing process. Using a substrate comprising a flexible portion may advantageously eliminate the need to pre-mold the substrate into a desired shape. The angle between the emitter and the sensor may be modified during or after manufacture of the aerosol-forming device.

[0035] The substrate can be bent so that the emitter and the sensor are adjacent to different parts of the cavity and so that the angle between the central optical axes of the emitter and the sensor is between 20 and 120 degrees, preferably between 60 and 100 degrees, and even more preferably between 70 and 90 degrees. Most preferably, the angle between the sensor and the emitter can be about 80 degrees.

[0036] The substrate may include a first portion, the first portion including the emitter. The substrate may include a second portion, the second portion including the sensor. The substrate may include a third portion between the first portion and the second portion. At least the third portion may be flexible so that the first portion is movable relative to the second portion. As described above, this may allow the angle between the emitter and the sensor to be controlled.

[0037] Preferably, the first part of the substrate may be rigid. The second part of the substrate may be rigid. In this way, the flexible third part acts as a hinge between the rigid first part and the second part.

[0038] Preferably, the third portion of the substrate may be opaque to the wavelengths of electromagnetic radiation emitted by the emitter. This may advantageously ensure that electromagnetic radiation emitted by the emitter is not directly received by the sensor before being reflected or absorbed by the aerosol-forming substrate received in the cavity and emitted.

[0039] The substrate may include one or more PCBs. The substrate may consist of one or more flexible PCBs. At least a third portion of the substrate may include or consist of a flexible PCB.

[0040] Preferably, the first and second portions of the substrate may include rigid PCBs, and the third portion may include a flexible PCB.

[0041] A particularly preferred combination may be a combination of a substrate including a flexible portion as described above and a shielding plate as described above when the shielding plate includes a first planar portion and a second planar portion, the second portion being planar in a plane different from the first portion. This is because the shielding plate can advantageously hold the substrate so that the flexible portion is bent at a desired angle.

[0042] Preferably, the shielding plate may be attached to a second side of the substrate opposite to the first side.The shielding plate may be rigid.

[0043] The first portion of the shielding plate may be attached to the first portion of the substrate.The second portion of the shielding plate may be attached to the second portion of the substrate.

[0044] This arrangement may allow for a simple manufacturing process. Advantageously, the act of attaching the shielding plate to the substrate may hold the substrate at a desired angle.

[0045] The shielding plate may include at least one clamp. The shielding plate may include a first clamp at a first end and a second clamp at a second end. The first end may be at an end of the shielding plate opposite to the second end. One or more clamps may be configured to connect the clamp to the second side of the substrate. The one or more clamps may advantageously provide a simple and low-cost means of attaching the shielding plate to the substrate. Attaching the shielding plate to the substrate in this manner may advantageously ensure that the manufacturing of the sensing assembly is simple and low-cost.

[0046] The shielding plate may be connected to a ground contact of the aerosol generating device. The ground contact may be on the substrate. If the substrate comprises a PCB, the ground contact may be on the PCB. At least one clamp of the shielding plate may be in contact with the ground contact. Connecting the shielding plate to the ground contact may allow the shielding plate to provide good shielding.

[0047] The shielding plate may be integrally formed. This may include at least one clamp. The shielding plate may be a one-piece piece. This may include at least one clamp.

[0048] The U-shaped section of the shielding plate may define a U-shape by means of a bottom wall and parallel first and second side walls.Preferably, the parallel first and second side walls of the U-shaped section of the shielding plate are non-coplanar with both the planar first and second parts of the shielding plate.

[0049] The first and second end edges of the U-shaped section may be defined by respective edges of the first and second side walls facing away from the bottom wall.The bottom wall and the parallel first and second side walls may both be arranged parallel to the longitudinal center axis of the cavity.

[0050] The first side wall and the second side wall of the U-shaped section of the shield plate may be arranged parallel to an angle bisector of an angle spanned between the non-coplanar first and second portions of the shield plate.

[0051] The bottom wall of the U-shaped section may include a curved or bent shape. The bottom wall of the U-shaped section may include a curved shape. The bottom wall of the U-shaped section may include a bent shape.

[0052] The aerosol generating device may comprise a housing.

[0053] The bottom wall of the U-shaped section may contact the inner side wall of the housing of the aerosol generating device. The bottom wall of the U-shaped section may include a curved or bent shape and may contact an inner side wall of a corresponding shape of the housing of the aerosol generating device. Therefore, the inner side wall may include a curved or bent shape that matches the curved or bent shape of the bottom wall of the U-shaped section in the area where the bottom wall of the U-shaped section contacts the inner side wall of the housing. This design may maximize the contact area between the shielding plate and the inner side wall of the housing. Due to the higher contact area, the heat dissipation from the shielding plate to the housing may be maximized.

[0054] The bottom wall of the U-shaped section may comprise one or more fins that contact the inner side wall of the housing of the aerosol generating device.The one or more fins may be used to dissipate heat from the shielding plate to the housing of the device.

[0055] At least a portion of an inner sidewall of a housing of the aerosol generating device in contact with the bottom wall of the U-shaped section may comprise graphene. A graphene sheet may be provided on an outer surface of the inner sidewall of the housing in contact with the bottom wall of the U-shaped section.

[0056] The sensing assembly may include an aerogel layer or sheet. The aerogel layer or sheet may be arranged between the substrate and the longitudinal center axis of the cavity. The aerogel layer or sheet may have a thickness between 0.1 mm and 0.3 mm, preferably about 0.2 mm. The aerogel layer or sheet may act as a thermal barrier. The aerogel layer or sheet may help to thermally insulate the substrate from the heater assembly. The aerogel layer or sheet may help to thermally insulate the substrate from the heated cavity during use.

[0057] The housing of the aerosol generating device may define a cavity. The housing of the aerosol generating device defining the cavity may include a first portion of the housing defining the cavity. The first portion of the housing defining the cavity may be transparent to at least one wavelength of electromagnetic radiation emitted by the emitter. The first portion of the housing may preferably be transparent to all wavelengths of electromagnetic radiation emitted by the emitter. The emitter may be configured to emit electromagnetic radiation into the cavity through the transparent portion.

[0058] The first part of the housing may separate the emitter from the cavity. Thus, the first part of the housing may protect the emitter from debris and dirt that may accumulate in the cavity. In particular, the emitter may be protected from residues of the aerosol-forming substrate that may accumulate during use of the aerosol generating device. The first part may also advantageously be easy to clean, so that the device can be simply maintained.

[0059] An air flow path may be defined through the aerosol generating device from the air inlet to the air outlet. The air flow path may pass through the cavity. The emitter may be separated from air flowing through the air flow path by a penetrable first portion of the housing. The air may carry debris or dirt. Thus, the first portion may protect the emitter from air passing through the air flow path.

[0060] The first portion of the housing may be sized and positioned to correspond to the viewing angle of the emitter.This may advantageously ensure that, in use, substantially all electromagnetic radiation emitted by the emitter is delivered into the cavity.

[0061] The housing of the aerosol generating device defining the cavity may include a second portion of the housing defining the cavity. The second portion of the housing defining the cavity may be transparent to at least one wavelength of electromagnetic radiation received by the sensor. The sensor may be configured to receive electromagnetic radiation from the cavity through the second transparent portion.

[0062] The second part of the housing may have corresponding features and advantages as described with respect to the first part, only with respect to the sensor and not with respect to the transmitter.

[0063] The arrangement of the first and second portions of the housing can advantageously increase the life of the sensing assembly. The first and second portions of the housing can prevent the sensing assembly from degrading over time, for example due to being covered with dirt, debris, and matrix residues. In a degraded sensing assembly, the amount of electromagnetic radiation entering the cavity from the transmitter or received from the cavity by the sensor may be reduced, which will reduce the accuracy and sensitivity of the sensing assembly.

[0064] The cavity of the aerosol generating device may have an open end into which the aerosol generating article is inserted. The open end may be a proximal end. The cavity may have a closed end opposite the open end. The closed end may be the base of the cavity. The closed end may be closed except for providing air holes arranged in the base. The base of the cavity may be flat. The base of the cavity may be circular. The base of the cavity may be arranged upstream of the cavity. The open end may be arranged downstream of the cavity. The cavity may have an elongated extension. The cavity may have a longitudinal central axis. The longitudinal direction may be a direction extending along the longitudinal central axis between the open end and the closed end. The longitudinal central axis of the cavity may be parallel to the longitudinal axis of the aerosol generating device.

[0065] At least a portion of the cavity may be configured as a heating chamber. A distal portion of the cavity may be configured as a heating chamber. The cavity may have a cylindrical shape. The cavity may have a hollow cylindrical shape. The shape of the cavity may correspond to the shape of the aerosol generating article to be received in the cavity. The cavity may have a circular cross-section. The cavity may have an elliptical or rectangular cross-section. The cavity may have an inner diameter corresponding to the outer diameter of the aerosol generating article.

[0066] The airflow channel may pass through the cavity. Ambient air may be drawn into the aerosol generating device through the airflow channel, into the cavity and towards the user. Downstream of the cavity, a mouthpiece may be arranged, or the user may draw directly on the aerosol generating article. The airflow channel may extend through the mouthpiece.

[0067] The aerosol generating device can be configured so that during operation of the device, the temperature of the sensing component does not exceed 120 degrees Celsius, preferably does not exceed 110 degrees Celsius, more preferably does not exceed 100 degrees Celsius, more preferably does not exceed 95 degrees Celsius, more preferably does not exceed 90 degrees Celsius, and more preferably does not exceed 87 degrees Celsius.

[0068] The sensor may be arranged between a longitudinal center axis of the cavity and at least a portion of the shielding plate.

[0069] The angle spanned between the non-coplanar first and second portions of the shield may be between 40 and 140 degrees, preferably between 80 and 120 degrees, more preferably between 90 and 110 degrees. The angle spanned between the non-coplanar first and second portions of the shield may be about 100 degrees. The angle will be measured between the inner surfaces of the first and second portions relative to the U-shape of the shield.

[0070] The sensor may be positioned between the first portion of the shielding plate and the cavity. The transmitter may be positioned between the second portion of the shielding plate and the cavity.

[0071] The aerosol generating device may include at least one lens configured to focus electromagnetic radiation received from the cavity onto the sensor. The lens may include an absorbent material configured to substantially block electromagnetic radiation having a wavelength falling outside a wavelength range. The absorbent material may be configured to substantially block electromagnetic radiation having a wavelength less than 200 nanometers and greater than 30,000 nanometers. The one or more lenses may advantageously increase the amount of electromagnetic radiation received by the sensor. This may advantageously increase the signal-to-noise ratio of the sensing assembly and thereby improve the accuracy of the sensing assembly when detecting the presence and type of an aerosol-forming substrate at least partially received in the cavity.

[0072] The cavity may be defined by a housing of the aerosol generating device.The first portion of the housing may be transparent to at least some wavelengths of electromagnetic radiation emitted by the emitter.The emitter may be configured to emit electromagnetic radiation into the cavity through the transparent portion.

[0073] The sensing assembly may include amplification electronics connected directly to the sensor.

[0074] The aerosol generating device may comprise a controller. The controller may be configured to receive a signal from the sensor. The controller may be configured to determine a material property of an aerosol-forming substrate at least partially received in the cavity based on a measured intensity of electromagnetic radiation received at the sensor. The controller may be configured to determine a material property of an aerosol-generating article comprising an aerosol-forming substrate based on a measured intensity of electromagnetic radiation received at the sensor.

[0075] Preferably, the controller may be configured to perform a spectral analysis of the measured intensity of the electromagnetic radiation to determine the material properties of the aerosol-forming substrate or an aerosol-generating article comprising the aerosol-forming substrate. Based on the determined material properties, the controller may be configured to determine the type of aerosol-forming substrate at least partially received in the cavity. The controller being configured to determine the material properties of the aerosol-forming substrate may advantageously mean that the type of aerosol-forming substrate may be determined directly based on the intrinsic material properties of the aerosol-forming substrate. It is not necessary for the aerosol-forming substrate or the aerosol-generating article comprising the aerosol-forming substrate to include a printed barcode, marker or other indicia of the type of substrate.

[0076] The material property determined by the controller may be the humidity or water content of the aerosol-forming substrate.

[0077] The controller may include a memory. Data correlating known measurements of electromagnetic radiation of a particular wavelength with the chemical structure or type of the aerosol-forming substrate may be stored in the memory of the controller. The controller may be configured to determine the type of aerosol-forming substrate received in the cavity by comparing one or more electromagnetic radiation measurements obtained by the sensor at one or more wavelengths with known measurements stored in the memory. The aerosol generating device may include a heating assembly for heating the aerosol-forming substrate. The heating assembly may be controlled by the controller. The controller may be configured to control the heating assembly according to a heating curve selected based on the determined type of aerosol-forming substrate.

[0078] The controller may be configured to repeatedly determine a value related to the water content of the aerosol-forming substrate received in the chamber during use of the aerosol generating device. Preferably, the controller may be configured to modify the heating curve based on a determined change in the water content of the aerosol-forming substrate. The determined change in water content may be relative to an expected water content of an aerosol-forming substrate of the determined type. Alternatively or in addition, the determined change in water content may be a change in the determined water content over time. For example, the determined change in water content may be a change in water content determined during a puff or between puffs.

[0079] The emitter may be configured to emit electromagnetic radiation having a wavelength between 1100 nanometers and 1500 nanometers.Preferably, the emitter may be configured to emit electromagnetic radiation having a wavelength between 1350 nanometers and 1400 nanometers.

[0080] The sensor may be configured to receive electromagnetic radiation having a wavelength between 1100 nanometers and 1500 nanometers. Preferably, the sensor may be configured to receive electromagnetic radiation having a wavelength between 1350 nanometers and 1400 nanometers.

[0081] Water is particularly effective at absorbing electromagnetic radiation at wavelengths between 1100 and 1500 nanometers, particularly between 1350 and 1400 nanometers. Therefore, when the relevant material property of the aerosol-forming substrate is humidity or water content, it may be advantageous for the emitter and sensor to transmit and receive electromagnetic radiation at such wavelengths.

[0082] The emitter may include at least one LED that emits electromagnetic radiation.

[0083] Preferably, the emitter may be configured to emit electromagnetic radiation of a plurality of wavelengths.The emitter may comprise a plurality of LEDs, each of the plurality of LEDs being configured to emit electromagnetic radiation of a different wavelength.

[0084] The sensor may include a photodiode.

[0085] The sensor may be configured to receive electromagnetic radiation at a plurality of wavelengths. In particular, the sensor may be configured to measure the received electromagnetic radiation at a plurality of wavelengths.

[0086] In other words, the sensing assembly may be configured to perform a spectral inspection of an aerosol-forming substrate received in the cavity or of an aerosol-generating article comprising a substrate received in the cavity. The apparatus may include a controller that performs a spectral analysis of the measured electromagnetic radiation. Based on the spectral analysis, the controller may be configured to determine whether an aerosol-forming substrate is present in the cavity. The controller may be configured to determine the type of aerosol-forming substrate in the cavity.

[0087] In this document, determining the presence and type of an aerosol-forming substrate is used interchangeably with determining the presence and type of an aerosol-generating article comprising an aerosol-forming substrate. In either case, the aerosol-generating device may advantageously be configured to determine the presence and type of an aerosol-forming substrate or article based on the chemical composition of the aerosol-forming substrate or article.

[0088] In one example, electromagnetic radiation emitted by the emitter may be incident on an aerosol-forming substrate, in which case the presence or type of the aerosol-forming substrate may be determined.

[0089] Alternatively, the aerosol-forming substrate may be contained in an aerosol-generating article. In this case, the electromagnetic radiation received by the sensor may be affected by the chemical structure of the aerosol-generating article, such as the packaging or housing of the article. Different aerosol-generating articles may include different chemical structures, such as different packaging or housing. This may allow different aerosol-generating articles to be identified.

[0090] "Different aerosol-generating articles" may refer to aerosol-generating articles comprising different aerosol-forming substrates.

[0091] Furthermore, a portion of the electromagnetic radiation may pass through the aerosol generating device to the aerosol-forming substrate, so that the electromagnetic radiation received by the sensor may be affected by the chemical structure of both the aerosol generating article and the substrate.

[0092] Aerosol formation substrate can be a solid aerosol formation substrate.Alternately, aerosol formation substrate can include both solid components and liquid components.Aerosol formation substrate can include tobacco-containing material, and tobacco-containing material is included in the volatile tobacco flavor compounds released from substrate when heated.Alternately, aerosol formation substrate can include non-tobacco material.Aerosol formation substrate can also include an aerosol forming agent that helps dense and stable aerosol formation.The example of suitable aerosol forming agent is glycerol and propylene glycol.

[0093] If aerosol formation substrate is solid aerosol formation substrate, then solid aerosol formation substrate can include (for example) one or more of the following: powder, granule, pellet, fragment, thin strip, strip or sheet, it contains one or more of herbaceous plant leaf, tobacco leaf, tobacco rib material, reconstituted tobacco, homogenized tobacco, extruded tobacco, cast leaf tobacco and expanded tobacco.Solid aerosol formation substrate can be in loose form, or can be provided in suitable container or tube.Alternatively, solid aerosol formation substrate can contain additional tobacco or non-tobacco volatile aroma compounds released when substrate is heated.Solid aerosol formation substrate can also contain capsule, and described capsule for example includes additional tobacco or non-tobacco volatile aroma compounds, and such capsule can melt during the heating period of solid aerosol formation substrate.

[0094] As used herein, homogenized tobacco refers to the material formed by agglomerating particle tobacco.Homogenized tobacco can be in the form of sheet.The homogenized tobacco material can have an aerosol forming agent with a dry weight content greater than 5%.Alternately, the homogenized tobacco material can have an aerosol forming agent with a dry weight content between 5 weight % and 30 weight %.The sheet of homogenized tobacco material can be formed by agglomerating particle tobacco, and the particle tobacco can be obtained by grinding one or both of tobacco leaf blade and tobacco leaf stem or otherwise combining.Alternately or in addition, the sheet of homogenized tobacco material can include one or more of tobacco dust, cigarette dust and other particle tobacco byproducts formed during, for example, disposal, processing and transportation of tobacco. The sheet of homogenized tobacco material may include one or more intrinsic binders as tobacco endogenous binders, one or more non-intrinsic binders as tobacco exogenous binders, or a combination thereof to help particulate tobacco agglomerate; alternatively or in addition, the sheet of homogenized tobacco material may include other additives, including but not limited to tobacco and non-tobacco fibers, aerosol formers, humectants, plasticizers, flavorings, fillers, aqueous solvents and non-aqueous solvents, and combinations thereof.

[0095] Alternatively, the solid aerosol formation matrix can be arranged on a heat-stable carrier or embedded in a heat-stable carrier. The carrier can take the form of a powder, a particle, a pellet, a fragment, a thin strip, a strip or a sheet. Alternatively, the carrier can be a tubular carrier, on its inner surface or on its outer surface or on its inner surface and outer surface, a solid matrix thin layer is deposited. Such tubular carriers can be formed by, for example, paper or paper-like material, nonwoven carbon fiber mat, low mass open mesh metal wire mesh (low mass openmesh metallic screen) or perforated metal foil or any other heat-stable polymer matrix.

[0096] In a particularly preferred embodiment, the aerosol-forming substrate comprises a gathered curled sheet of homogenized tobacco material. As used herein, the term "curled sheet" means a sheet with a plurality of substantially parallel ridges or folds. Preferably, when the aerosol-generating article has been assembled, the substantially parallel ridges or folds extend along or parallel to the longitudinal axis of the aerosol-generating article. This advantageously promotes the gathering of the curled sheet of homogenized tobacco material to form an aerosol-forming substrate. However, it should be understood that the curled sheet of the homogenized tobacco material included in the aerosol-generating article can alternatively or additionally have a plurality of substantially parallel ridges or folds that are arranged at an acute angle or an obtuse angle with the longitudinal axis of the aerosol-generating article when the aerosol-generating article has been assembled. In certain embodiments, the aerosol-forming substrate can comprise a gathered sheet of homogenized tobacco material, and the gathered sheet is substantially uniformly textured on substantially its entire surface. For example, the aerosol-forming substrate may comprise a gathered crimped sheet of homogenised tobacco material comprising a plurality of substantially parallel ridges or corrugations that are generally evenly spaced across the width of the sheet.

[0097] The solid aerosol-forming substrate may be deposited on the surface of the carrier in the form of, for example, a sheet, foam, gel or slurry. The solid aerosol-forming substrate may be deposited on the entire surface of the carrier, or alternatively, may be deposited in a pattern to provide uneven flavour delivery during use.

[0098] The aerosol generating device may include a heater assembly. The heater assembly may be configured to heat an aerosol-forming substrate received in the cavity when in use. The controller may be configured to control the heater assembly. Control of the heater assembly may be based on a type of aerosol-forming substrate determined by the controller. Preferably, the controller may be configured to control the heater assembly according to a heating curve. The heating curve may be selected or modified according to the type of aerosol-forming substrate at least partially received in the cavity.

[0099] The heater assembly may include a heating element. In use, power may be supplied to the heating element, causing the heating element to heat up. The heat may then be transferred to the received aerosol-forming substrate, for example by conduction through the device housing of the forming chamber.

[0100] The heating element may be a resistive heating element. The heating element may include a resistive material. Suitable resistive materials include, but are not limited to, semiconductors such as doped ceramics, electrically "conductive" ceramics (e.g., molybdenum disilicide), carbon, graphite, metals, metal alloys, and composite materials made of ceramic and metallic materials. Such composite materials may include doped or undoped ceramics.

[0101] In another example, the heater assembly may include one or more inductor coils and the heating element may include one or more susceptor elements.

[0102] The one or more susceptor elements may be configured to be heated by an alternating magnetic field generated by one or more inductor coils. In use, the power supplied to the inductor coil (e.g., by the power supply of the device) may cause the inductor coil to induce eddy currents in the susceptor element. These eddy currents then cause the susceptor element to generate heat. Power is supplied to the inductor coil as an alternating magnetic field. The alternating current may have any suitable frequency. The alternating current may preferably be a high frequency alternating current. The alternating current may have a frequency between 100 kilohertz (kHz) and 30 megahertz (MHz). When the aerosol-forming substrate is received in the chamber, the heat generated by the susceptor element may heat the aerosol-forming substrate to a temperature sufficient to release the aerosol from the substrate. The susceptor element may be formed by a material having the ability to absorb electromagnetic energy and convert it into heat. By way of example and not limitation, the susceptor element may be formed by a ferromagnetic material (such as steel).

[0103] The aerosol generating device may comprise a power source, which may be configured to supply electric current to the resistive heating element.

[0104] The heating element may comprise a substrate layer of a flexible material. The substrate layer may comprise a thermally stable polymer, preferably a polyimide.

[0105] The heating element may be arranged on the substrate layer. The heating element may include a wire connection configured for connection to a controller of the aerosol generating device. The heating element may include a heating rail arranged on the substrate layer. The heating rail may include a thermally conductive material, preferably a metal such as stainless steel. The heating rail may be electrically connected to the wire connection.

[0106] The heating element may take other forms. For example, one or more metal grids, flexible printed circuit boards, molded interconnect devices (MIDs), ceramic heaters, and flexible carbon fiber heaters may be formed on a substrate of a suitable shape using a coating technique such as plasma vapor deposition.

[0107] As used herein, in the context of a permeable portion or otherwise, permeability to certain wavelengths of electromagnetic radiation means that at least 90%, preferably at least 95%, and even more preferably at least 99% of the electromagnetic radiation of said wavelength can pass through the first portion or the second portion without being absorbed.

[0108] The present invention also relates to a sensing assembly for an aerosol generating device for generating an aerosol from an aerosol-forming substrate. The aerosol generating device may include a housing. The housing may define a cavity. The cavity may be used to at least partially receive the aerosol-forming substrate. The sensing assembly may include an emitter configured to emit electromagnetic radiation into the cavity. The sensing assembly may include a sensor configured to measure a wavelength of received electromagnetic radiation. The sensing assembly may include a shielding plate configured to block electromagnetic radiation. The shielding plate may be positioned outside the cavity so that the sensor is arranged between the cavity and at least a portion of the shielding plate. The shielding plate may include a U-shaped section. The shielding plate may include a planar first portion. The planar first portion may be connected to a first end edge of the U-shaped section. The shielding plate may include a planar second portion. The planar second portion may be connected to a second end edge of the U-shaped section. The first portion and the second portion of the shielding plate may be non-coplanar.

[0109] The sensing assembly may include any of the features described in relation to any of the previous aspects of the disclosure.

[0110] The present invention also relates to an aerosol generating system comprising an aerosol generating device as described herein and an aerosol generating article comprising an aerosol-forming substrate.

[0111] As used herein, the terms “proximal”, “distal”, “upstream” and “downstream” are used to describe the relative position of components or parts of components of an aerosol generating device relative to the direction in which a user draws puffs on the aerosol generating device during use.

[0112] As used herein, an "aerosol generating device" relates to a device that interacts with an aerosol-forming substrate to generate an aerosol. The aerosol-forming substrate may be part of an aerosol-generating article, such as a smoking article. The aerosol generating device may be a smoking device that interacts with an aerosol-forming substrate of an aerosol-generating article to generate an aerosol that can be inhaled directly into the user's lungs through the user's mouth. The aerosol generating device may be a holder. The device may be an electrically heated smoking device. The aerosol generating device may include a housing, an electrical circuit, a power supply, a heating chamber, and a heating element.

[0113] As used herein, the term "aerosol-generating article" refers to an article comprising an aerosol-forming substrate capable of releasing volatile compounds that can form an aerosol. For example, the aerosol-generating article may be a smoking article that generates an aerosol that can be inhaled directly into the user's lungs through the user's mouth. The aerosol-generating article may be disposable.

[0114] As used herein, the term "aerosol-forming substrate" relates to a substrate capable of releasing one or more volatile compounds that can form an aerosol. Such volatile compounds may be released by heating the aerosol-forming substrate. The aerosol-forming substrate may suitably be part of an aerosol-generating article or a smoking article.

[0115] A non-exhaustive list of non-limiting examples is provided below.Any one or more features of these examples may be combined with any one or more features of another example, embodiment or aspect described herein.

[0116] Example E1: An aerosol generating device comprising a cavity for receiving an aerosol-forming substrate and a sensing component for detecting the aerosol-forming substrate in the cavity, the sensing component comprising

[0117] an emitter configured to emit electromagnetic radiation into the cavity;

[0118] a sensor configured to measure received electromagnetic radiation of a wavelength; and

[0119] a shielding plate configured to block electromagnetic radiation and positioned outside the cavity such that the sensor is disposed between the cavity and at least a portion of the shielding plate;

[0120] wherein the shielding plate comprises a U-shaped section, a planar first portion connected to a first end edge of the U-shaped section, and a planar second portion connected to a second end edge of the U-shaped section, and

[0121] The first portion and the second portion of the shielding plate are non-coplanar.

[0122] Example E2: An aerosol generating device according to example E1, wherein the U-shaped section defines a U-shape by means of a bottom wall and parallel first and second side walls, and

[0123] Wherein the first end edge and the second end edge are defined by respective edges of the first side wall and the second side wall facing away from the bottom wall, preferably,

[0124] Wherein the bottom wall and the parallel first and second side walls are both arranged parallel to the longitudinal center axis of the cavity.

[0125] Example E3: An aerosol generating device according to example E2, wherein the first and second side walls of the U-shaped section of the shielding plate are arranged parallel to the bisector of the angle spanned between the non-coplanar first and second portions of the shielding plate.

[0126] Example E4: An aerosol generating device according to example E2 or example E3, wherein the bottom wall of the U-shaped section comprises a curved or bent shape.

[0127] Example E5: An aerosol-generating device according to example E4, wherein a bottom wall of the U-shaped section contacts an inner side wall of a housing of the aerosol-generating device.

[0128] Example E6: An aerosol-generating device according to example E5, wherein the bottom wall of the U-shaped section comprises one or more fins in contact with the inner side wall of the housing of the aerosol-generating device.

[0129] Example E7: An aerosol generating device according to Example E5, wherein the inner side wall of the shell of the aerosol generating device includes a curved or bent shape that matches the curved or bent shape of the bottom wall of the U-shaped section in the area where the bottom wall of the U-shaped section contacts the inner side wall of the shell of the aerosol generating device.

[0130] Example E8: An aerosol-generating device according to any of Examples E5 to E7, wherein at least a portion of an inner side wall of a housing of the aerosol-generating device in contact with the bottom wall of the U-shaped section comprises graphene.

[0131] Example E9: An aerosol generating device according to any of the preceding examples, wherein during operation of the device, the temperature of the sensing component does not exceed 120 degrees Celsius, preferably does not exceed 110 degrees Celsius, more preferably does not exceed 100 degrees Celsius, more preferably does not exceed 95 degrees Celsius, more preferably does not exceed 90 degrees Celsius, and more preferably does not exceed 87 degrees Celsius.

[0132] Example E10 An aerosol-generating device according to any of the preceding examples, wherein the sensor is arranged between a longitudinal central axis of the cavity and at least a portion of the shielding plate.

[0133] Example E11: An aerosol generating device according to any of the preceding examples, wherein the shielding plate comprises phosphor bronze, preferably nickel-plated phosphor bronze.

[0134] Example E12: An aerosol generating device according to any one of the preceding examples, wherein the shielding plate comprises a conductive material having a conductivity of at least 1×10 6 Siemens / meter.

[0135] Example E13: An aerosol-generating device according to any of the preceding examples, wherein the shielding plate comprises a thermally conductive material having a thermal conductivity of at least 10 Watts / meter-Kelvin.

[0136] Example E14: An aerosol generating device according to any of the preceding examples, wherein the angle spanned between the non-coplanar first and second portions of the shielding plate is between 40 and 140 degrees, preferably between 80 and 120 degrees, more preferably between 90 and 110 degrees, and more preferably about 100 degrees.

[0137] Example E15 An aerosol-generating device according to any of the preceding examples, wherein the sensor is positioned between a first portion of the shielding plate and the cavity, and the emitter is positioned between a second portion of the shielding plate and the cavity.

[0138] Example E16: An aerosol generating device according to any of the preceding examples, further comprising at least one lens configured to focus electromagnetic radiation received from the cavity onto the sensor, the lens comprising an absorbing material configured to substantially block electromagnetic radiation having a wavelength outside a wavelength range.

[0139] Example E17: An aerosol generating device according to example E16, wherein the absorbent material is configured to substantially block electromagnetic radiation having a wavelength less than 200 nanometers and greater than 30,000 nanometers.

[0140] Example E18: An aerosol generating device according to any of the preceding examples, wherein the cavity is defined by a shell of the device, and wherein a first portion of the shell is transparent to at least some wavelengths of electromagnetic radiation emitted by the emitter, and wherein the emitter is configured to emit the electromagnetic radiation into the cavity through the transparent portion.

[0141] Example E19: An aerosol generating device according to any of the preceding examples, wherein the sensing component further comprises a substrate, the substrate having a first side, the emitter and the sensor being attached to the first side, a first portion of the substrate comprising the emitter, a second portion of the substrate comprising the sensor, wherein the substrate further comprises a third portion between the first portion and the second portion, and wherein at least the third portion is flexible so that the first portion is movable relative to the second portion.

[0142] Example E20: An aerosol generating device according to any of the preceding examples, wherein the sensing assembly further comprises amplification electronics directly connected to the sensor.

[0143] Example E21: An aerosol generating device according to any of the preceding examples, further comprising a controller configured to receive a signal from the sensor, wherein the controller is configured to determine material properties of the aerosol-forming substrate at least partially received in the cavity or an aerosol-generating article including the aerosol-forming substrate based on a measured intensity of the electromagnetic radiation received at the sensor.

[0144] Example E22 An aerosol-generating device according to example E21, wherein the material property determined by the controller is humidity or water content of the aerosol-forming substrate.

[0145] Example E23: An aerosol-generating device according to any of the preceding examples, wherein the shielding plate comprises at least one clamp.

[0146] Example E24: An aerosol generating device according to example E23, wherein the shielding plate comprises a first clamp at a first end and a second clamp at a second end, the first end being at an end of the shielding plate opposite to the second end.

[0147] Example E25: An aerosol-generating device according to Example E23 or Example E24, wherein the at least one clamp, or the first clamp and the second clamp, are configured to connect the shielding plate to a substrate.

[0148] Example E26: An aerosol generating device according to any of the preceding examples, wherein the shielding plate is integrally formed, preferably wherein the shielding plate is a unitary piece.

[0149] Example E27: An aerosol-generating system comprising an aerosol-generating device according to any of the preceding examples and an aerosol-generating article comprising the aerosol-forming substrate.

[0150] Features described with respect to one embodiment may be equally applicable to other embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0151] The present invention will be further described, by way of example only, with reference to the accompanying drawings, in which:

[0152] Figure 1 An aerosol generating system is shown;

[0153] Figure 2 a and 2b show the sensing assembly;

[0154] Figure 3 a and 3b show shielding plates;

[0155] Figure 4 The sensing assembly is shown; and

[0156] Figure 5 5a and 5b show an aerosol generating device. DETAILED DESCRIPTION

[0157] Figure 1 The aerosol generating system 10 is shown in a cross-sectional view. The aerosol generating system 10 comprises an aerosol generating article 12. The aerosol generating article 12 comprises an aerosol-forming substrate 14 at a distal portion thereof. The aerosol generating system 10 further comprises an aerosol generating device 20. The aerosol generating device 20 comprises a cavity 22 for receiving the aerosol-forming substrate 14. The cavity 22 is defined by a housing 24 of the aerosol generating device 20.

[0158] exist Figure 1 In the configuration shown in , the distal portion of the aerosol-generating article 12 including the aerosol-forming substrate 14 has been inserted into the cavity 22. The aerosol-forming substrate 14 may be a solid tobacco-containing substrate. In particular, the aerosol-forming substrate 14 may be a gathered sheet of homogenized tobacco.

[0159] like Figure 1 As shown in , the aerosol-generating article 12 and the cavity 22 are configured so that when the aerosol-generating article 12 is received in the cavity 22, the mouth end of the aerosol-generating article 12 protrudes out of the cavity 22 and out of the aerosol-generating device 20. The mouth end forms a mouthpiece 16 on which a user of the aerosol-generating device can draw during use.

[0160] The aerosol generating device 20 comprises a heater assembly including a heating element 26. The heating element 26 surrounds the cavity 22 along a portion of the cavity 22 in which the aerosol-forming substrate 14 of the aerosol-generating article 12 is received. In alternative embodiments, the heating element 26 may form a portion of the housing 24 that defines the portion of the cavity 22 in which the aerosol-forming substrate 14 is received. The heating element 26 may be a resistive heating element.

[0161] The airflow channel 28 extends from an air inlet 30 of the aerosol generating device 20. Upstream of the cavity 22, the airflow channel 28 is primarily defined by an airflow channel wall 32. Downstream of the airflow channel wall 32, the airflow channel 28 passes through an air inlet defined in a base 34 of the cavity 22. The airflow channel 28 then extends through the cavity 22. When the aerosol generating article 12 is received in the cavity 22, the airflow channel 28 passes through the aerosol generating article 12 and extends through the mouthpiece 16.

[0162] The aerosol generating device 20 also includes a power source 36 in the form of a rechargeable battery for powering the heating element 26 controllable by the controller 38. The power source 36 is connected to the controller 38 and the heating element 26 via wires and connections not shown in the figure. The aerosol generating device 20 may include other elements not shown in the figure, such as a button for activating the aerosol generating device 20.

[0163] The aerosol generating device 20 further comprises a sensing assembly 40 for detecting the aerosol-forming substrate 14 in the cavity 22 .

[0164] Figure 2 a shows the sensing assembly 40 more clearly. Figure 2 a is a perspective view of the sensing assembly 40 with a cut-away portion of the aerosol generating device 20 .

[0165] Sensing assembly 40 includes an emitter 42. Emitter 42 includes a plurality of LEDs. Each of these LEDs is configured to emit electromagnetic radiation of a different wavelength. Emitter 42, and in particular the plurality of LEDs of emitter 42, is configured to emit electromagnetic radiation into cavity 22. Emitter 42 is configured to emit electromagnetic radiation having a wavelength between 1350 and 1400 nanometers.

[0166] like Figure 1 As shown in FIG, the housing 24 defining a portion of the cavity 22 includes a first penetrable portion 23. The emitter 42 is separated from the cavity 22 by the first penetrable portion 23 and is configured to emit electromagnetic radiation into the cavity 22 through the first penetrable portion 23. The provision of the first penetrable portion 23 protects the emitter 42 from debris and dirt that may accumulate in the cavity 22 after long-term use of the device 20, and can be easily cleaned.

[0167] like Figure 2 As shown in FIG. 1 , the sensing assembly 40 further includes a sensor 44. The sensor 44 is configured to receive electromagnetic radiation from the cavity 22. In particular, the sensor 44 is configured to receive electromagnetic radiation from the cavity 22, which is emitted by the emitter 42 and then reflected or transmitted by the aerosol generating article 12 toward the sensor 44. The sensor 44 includes a photodiode. The sensor 44 is configured to measure the received electromagnetic radiation of multiple wavelengths. In particular, the sensor 44 is configured to measure the intensity of the received electromagnetic radiation of multiple wavelengths. The sensor 44 is configured to receive electromagnetic radiation with a wavelength between 1350 and 1400 nanometers.

[0168] The cavity 22 includes a second penetrable portion, not shown in the figure. The sensor 44 is separated from the cavity 22 by the second penetrable portion and is configured to receive electromagnetic radiation from the cavity 22 through the second penetrable portion.

[0169] The sensing assembly 40 also includes a substrate in the form of a printed circuit board (PCB) 50. A first portion 52 of the PCB 50 includes the transmitter 42. A second portion 54 of the PCB 50 includes the sensor 44. Both the first portion 52 and the second portion 54 of the PCB 50 are planar. The PCB 50 also includes a third portion 56 that is flexible. Figure 2 As shown most clearly in FIGS. 4 and 5 , the third portion 56 has been bent so that the angle between the first portion 52 and the second portion 54 is 100 degrees. Therefore, the angle between the normal to the first portion 52 and the normal to the second portion 54 is 80 degrees. This also means that the angle between the central optical axis of the emitter 42 and the central optical axis of the sensor 44 is 80 degrees (see FIG. 4 ). Figure 2 b). This provides the best optical performance.

[0170] The third portion 56 is opaque to the wavelengths of electromagnetic radiation emitted by the emitter 42. This ensures that the electromagnetic radiation emitted by the emitter 42 is not directly received by the sensor 44. The PCB 50 includes an additional flexible portion that allows the PCB 50 to be folded into a Figure 2 The shapes shown in a and 4.

[0171] Figure 2 b shows the angles between the aerosol-generating article 12 , the emitter 42 and the sensor 44 . Figure 2 b is a cross section of the aerosol generating article 12 and the emitter 42 and sensor 44 separated from the rest of the device 20. The optimal angle between the central optical axis 42a of the emitter 42 and the central optical axis 44a of the sensor 44 is 80 degrees. Figure 2 In b, it is represented by the number 43.

[0172] The sensing assembly 40 further includes a shielding plate 60. The shielding plate 60 is Figure 2 Not shown in a, but Figure 3 a and 3b.

[0173] Figure 3 3a and 3b show the shielding plate 60 separated from the rest of the sensing assembly 40. Figure 3 a shows the shielding plate 60 in a perspective view. Figure 3 b shows the shielding plate 60 in a top view.

[0174] The shield plate 60 includes a U-shaped section 62 , a planar first portion 64 connected to a first end edge 66 of the U-shaped section 62 , and a planar second portion 68 connected to a second end edge 70 of the U-shaped section 62 .

[0175] The first portion 64 and the second portion 68 of the shield plate 60 are non-coplanar.

[0176] The U-shaped section 62 defines a U-shape by means of a bottom wall 72 having a slightly curved shape and a first side wall 74 and a second side wall 76 , which are parallel.

[0177] The first end edge 66 and the second end edge 70 are defined by respective edges of a first side wall 74 and a second side wall 76 facing away from the bottom wall 72 .

[0178] The first side wall 74 and the second side wall 76 of the U-shaped section 62 of the shield plate 60 are arranged parallel to the angle bisector 78 of the angle 80 spanned between the non-coplanar first and second portions 64 , 68 of the shield plate 60 .

[0179] The angle 80 spanned between the non-coplanar first and second portions 64, 68 of the shield plate 60 is approximately 100 degrees. The angle 80 is measured between the inner surfaces of the first and second portions 64, 68 relative to the U-shape of the shield plate 60.

[0180] The shielding plate 60 also includes a first clamp 82 at a first end at an end of the shielding plate 60 opposite to the second end and a second clamp 84 at a second end. The first clamp 82 and the second clamp 84 are configured to connect the shielding plate 60 to the PCB 50. The shielding plate 60 is integrally formed as a unitary piece.

[0181] Figure 4 Another cross-sectional perspective view of a section of the aerosol generating device 20 including the sensing assembly 40 is shown (but not identical to the Figure 2 a, viewed towards the cavity from approximately the opposite direction). Figure 4 Several parts of the sensing assembly 40, namely the shielding plate 60, the PCB 50, and the aerogel 86, are shown in exploded view. In the assembled configuration, these components are attached on top of each other. The shielding plate 60 is configured to block electromagnetic radiation and is positioned outside the cavity so that the sensor 44 is arranged between the cavity 22 and at least a portion of the shielding plate 60. In the embodiment shown, both the sensor 44 and the transmitter 42 are positioned between the shielding plate 60 and the cavity 22. In this way, electromagnetic radiation outside the cavity 22 and the sensing assembly 40 is blocked from reaching the transmitter 42, and more importantly, from reaching the sensor 44. This means that the amount of external electromagnetic radiation received at the sensor 44 is greatly reduced or eliminated, and is therefore not detected as noise at the sensor 44.

[0182] The shielding plate 60 is rigid enough so that it can maintain and hold the first portion 52 of the PCB 50 relative to the second portion 54 such that the angle between the normal to the first portion 52 and the normal to the second portion 54 is 80 degrees.

[0183] exist Figure 4It can also be seen in FIG. 2 that the bottom wall 72 and the parallel first and second side walls 74 , 76 of the shielding plate 60 are both arranged parallel to the longitudinal center axis 21 of the cavity 22 .

[0184] The shielding plate 60 may be made of aluminum, which is electrically conductive and thus reflects or absorbs external electromagnetic radiation. Aluminum is also a thermally conductive material. Preferably, the shielding plate 60 is made of phosphor bronze, preferably nickel-plated phosphor bronze. The shielding plate 60 being made of a thermally conductive material means that the shielding plate 60 is suitable for dissipating heat from the sensor 44 and the transmitter 42.

[0185] like Figure 1 As can be seen in FIG, the sensing assembly 40 is positioned relatively close to the heating element 26. Therefore, during use of the aerosol generating device 20, when current passes through the heating element 26 and heats it, heat will inevitably be transferred from the heating element 26 to the sensing assembly 40. The emitter 42 and the sensor 44 may be damaged when they are overheated. The shielding plate 60 dissipates heat from the emitter 42 and the sensor 44, thereby reducing the risk of damage to the emitter 42 and the sensor 44.

[0186] Figure 5 a shows Figure 4 2 is a cross-sectional top view of an aerosol generating device 20. A bottom wall 72 and parallel first and second side walls 74, 76 of the shielding plate 60 are visible. The bottom wall 72 of the U-shaped section 62 comprises a curved shape. The curved bottom wall 72 of the U-shaped section 62 contacts a correspondingly shaped portion of the inner side wall 25 of the housing 24 of the aerosol generating device 20. Thus, the inner side wall 25 of the housing 24 cooperates with the curved shape of the bottom wall 72 of the U-shaped section 62 in the area where the bottom wall 72 contacts the inner side wall 25.

[0187] Preferably, at least a portion of the inner side wall 25 that contacts the bottom wall 72 includes graphene. Preferably, a graphene sheet is disposed on the surface of the inner side wall 25. The shape of the bottom wall 72 of the U-shaped section 62 is rounded to have the same radius of curvature as the graphene sheet. This design can maximize the contact between the shielding plate 60 and the graphene sheet. Therefore, due to the high thermal conductivity of the graphene sheet, heat dissipation can be maximized.

[0188] Figure 5 b shows a cross-sectional top view of an aerosol generating device 20 including a different design of a shielding plate 60. Figure 5 In the embodiment of FIG. 1 b, the U-shaped section 62 includes a plurality of fins 88 that contact the inner side wall 25 of the housing 24 of the aerosol generating device 20. Thus, the fins 88 may beneficially conduct heat away from the shielding plate 60 toward the housing 24.

[0189] like Figure 1As shown in , when the aerosol generating device 20 is used, the aerosol generating article 12 is received in the cavity 22. The sensing assembly 40 is combined with the controller 38 to detect the presence of the aerosol generating article 12. The emitter 42 of the sensing assembly 40 emits electromagnetic radiation of multiple wavelengths. The radiation is then reflected and / or transmitted by the aerosol generating article 12. Because the viewing angles of the emitter 42 and the sensor 44 substantially overlap when the angle between the central optical axis of the emitter 42 and the central optical axis of the sensor 44 is 80 degrees, a large amount of reflected and / or transmitted electromagnetic radiation is received by the sensor 44. The sensor 44 measures the intensity of the received electromagnetic radiation of various wavelengths. In this way, the sensor 44 generates electrical signals. These electrical signals are directly transmitted to the amplification electronics to be amplified before being received at the controller 38. The controller 38 is configured to perform spectral analysis on the measured values ​​of the intensity of electromagnetic radiation of different wavelengths. This includes comparing the intensity of electromagnetic radiation of different wavelengths with the known intensity distribution emitted by the emitter 42. Based on the spectral analysis, the controller 38 is configured to determine whether the aerosol-generating article 12 is present.

[0190] The controller 38 is also configured to determine the type of aerosol generating article 12 based on the spectral analysis. Different types of aerosol generating articles 12 may be received in the cavity 22. In particular, aerosol generating articles 12 having aerosol-forming substrates 14 of different chemical properties may be received in the cavity 22. Because the aerosol generating article 12 and the aerosol-forming substrate have different chemical and / or other material properties, different aerosol generating articles 12 will reflect or transmit electromagnetic radiation of multiple wavelengths emitted by the emitter 42 to different degrees. This will mean that the spectrum of the electromagnetic radiation received by the sensor 44 will be different for different aerosol generating articles 12. The spectrum of a particular type of aerosol generating article 12 is predictable. Therefore, based on the spectral analysis, the controller 38 can determine the type of aerosol generating article 12 received in the cavity 22.

[0191] The controller 38 is configured to control the heating element 26 according to an appropriate heating curve for the determined type of aerosol-generating article 12 .

[0192] Based on the spectral analysis, the controller 38 is also configured to determine a material property of the aerosol-generating article 12 received in the cavity 22. In particular, the controller 38 is configured to determine a material property of the aerosol-forming substrate 14 of the aerosol-generating article 12. The material property determined by the controller 38 is the humidity or moisture content of the aerosol-forming substrate.

[0193] The controller 38 is configured to determine a value related to the water content of the aerosol-forming substrate 14 received in the cavity 22 based on the measured intensity of the electromagnetic radiation received at the sensor 44. As described above, the transmitter 42 and the sensor 44 are configured to emit and receive electromagnetic radiation having a wavelength between 1350 nanometers and 1400 nanometers, respectively. Water is particularly effective in absorbing electromagnetic radiation in this range. Therefore, the radiation intensity received by the sensor 44 is highly dependent on the water content of the aerosol-forming substrate 14, and the controller 38 is able to determine a value associated with the water content of the aerosol-forming substrate 14 based on a spectral analysis of the electromagnetic radiation received by the sensor 44.

Claims

1. An aerosol generating device, the aerosol generating device comprising a cavity for receiving an aerosol-forming substrate and a sensing component for detecting the aerosol-forming substrate in the cavity, the sensing component comprising an emitter configured to emit electromagnetic radiation into the cavity; a sensor configured to measure received electromagnetic radiation of a wavelength; as well as a shielding plate configured to block electromagnetic radiation and positioned outside the cavity such that the sensor is disposed between the cavity and at least a portion of the shielding plate; wherein the shielding plate comprises a U-shaped section, a planar first portion connected to a first end edge of the U-shaped section, and a planar second portion connected to a second end edge of the U-shaped section, and The first portion and the second portion of the shielding plate are non-coplanar.

2. An aerosol generating device according to claim 1, wherein the U-shaped section defines a U-shape by means of a bottom wall and parallel first and second side walls, and Wherein the first end edge and the second end edge are defined by respective edges of the first side wall and the second side wall facing away from the bottom wall, preferably, Wherein the bottom wall and the parallel first and second side walls are both arranged parallel to the longitudinal center axis of the cavity.

3. An aerosol generating device according to claim 2, wherein the first and second side walls of the U-shaped section of the shielding plate are arranged parallel to the bisector of the angle spanned between the non-coplanar first and second parts of the shielding plate.

4. An aerosol generating device according to claim 2 or claim 3, wherein the bottom wall of the U-shaped section comprises a curved or bent shape.

5. An aerosol generating device according to claim 4, wherein a bottom wall of the U-shaped section contacts an inner side wall of a housing of the aerosol generating device.

6. An aerosol generating device according to claim 5, wherein the bottom wall of the U-shaped section comprises one or more fins in contact with the inner side wall of the housing of the aerosol generating device.

7. An aerosol generating device according to claim 5, wherein the inner side wall of the shell of the aerosol generating device includes a curved or bent shape that matches the curved or bent shape of the bottom wall of the U-shaped section in the area where the bottom wall of the U-shaped section contacts the inner side wall of the shell of the aerosol generating device.

8. An aerosol generating device according to any one of claims 5 to 7, wherein at least a portion of an inner side wall of a housing of the aerosol generating device in contact with the bottom wall of the U-shaped section comprises graphene.

9. An aerosol generating device according to any one of the preceding claims, wherein during operation of the device, the temperature of the sensing component does not exceed 120 degrees Celsius, preferably does not exceed 110 degrees Celsius, more preferably does not exceed 100 degrees Celsius, more preferably does not exceed 95 degrees Celsius, more preferably does not exceed 90 degrees Celsius, and more preferably does not exceed 87 degrees Celsius.

10. An aerosol generating device according to any preceding claim, wherein the sensor is arranged between a longitudinal centre axis of the cavity and at least a portion of the shielding plate.

11. An aerosol generating device according to any preceding claim, wherein the shielding plate comprises phosphor bronze, preferably nickel-plated phosphor bronze.

12. An aerosol generating device according to any one of the preceding claims, wherein the shielding plate comprises a conductive layer having an electrical conductivity of at least 1×10 6 Siemens / meter of conductive material.

13. An aerosol generating device according to any one of the preceding claims, wherein the shielding plate comprises a thermally conductive material having a thermal conductivity of at least 10 Watts / meter-Kelvin.

14. An aerosol generating device according to any of the preceding claims, wherein the angle spanned between the non-coplanar first and second portions of the shielding plate is between 40 and 140 degrees, preferably between 80 and 120 degrees, more preferably between 90 and 110 degrees, and more preferably about 100 degrees.

15. An aerosol generating device according to any preceding claim, wherein the sensor is positioned between a first portion of the shielding plate and the cavity, and the emitter is positioned between a second portion of the shielding plate and the cavity.

16. An aerosol generating device according to any of the preceding claims, further comprising at least one lens configured to focus electromagnetic radiation received from the cavity onto the sensor, the lens comprising an absorbing material configured to substantially block electromagnetic radiation having a wavelength outside a wavelength range.

17. An aerosol generating device according to claim 16, wherein the absorbent material is configured to substantially block electromagnetic radiation having a wavelength less than 200 nanometers and greater than 30,000 nanometers.

18. An aerosol generating device according to any of the preceding claims, wherein the cavity is defined by a shell of the device, and wherein a first portion of the shell is transparent to at least some wavelengths of electromagnetic radiation emitted by the emitter, and wherein the emitter is configured to emit the electromagnetic radiation into the cavity through the transparent portion.

19. An aerosol generating device according to any of the preceding claims, wherein the sensing component further comprises a substrate, the substrate having a first side, the emitter and the sensor being attached to the first side, a first portion of the substrate comprising the emitter, a second portion of the substrate comprising the sensor, wherein the substrate further comprises a third portion between the first portion and the second portion, and wherein at least the third portion is flexible so that the first portion is movable relative to the second portion.

20. An aerosol generating device according to any preceding claim, wherein the sensing assembly further comprises amplification electronics connected directly to the sensor.

21. An aerosol generating device according to any of the preceding claims, further comprising a controller configured to receive a signal from the sensor, wherein the controller is configured to determine material properties of the aerosol-forming substrate at least partially received in the cavity or an aerosol-generating article including the aerosol-forming substrate based on a measured intensity of the electromagnetic radiation received at the sensor.

22. An aerosol generating device according to claim 21, wherein the material property determined by the controller is the humidity or water content of the aerosol-forming substrate.

23. An aerosol generating device according to any preceding claim, wherein the shielding plate comprises at least one clamp.

24. An aerosol generating device according to claim 23, wherein the shielding plate comprises a first clamp at a first end and a second clamp at a second end, the first end being at an end of the shielding plate opposite to the second end.

25. An aerosol generating device according to claim 23 or claim 24, wherein the at least one clamp, or the first clamp and the second clamp, are configured to connect the shielding plate to a substrate.

26. An aerosol generating device according to any preceding claim, wherein the shielding plate is integrally formed, preferably wherein the shielding plate is a one-piece piece.

27. An aerosol generating system comprising an aerosol generating device according to any preceding claim and an aerosol generating article comprising the aerosol-forming substrate.

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