Smoking Substitution System

Abstract

A non-combustion heated device having a thermostatic heater control is provided, and a puff is determined to have occurred by monitoring the heater activation period for exceeding a threshold value. It has been found that determining a puff from monitoring the heater activation period against a threshold value advantageously allows for detection of weaker puffs that a flow sensor may miss. For example, a flow sensor may be able to detect a puff having an average flow rate of 55 ml / sec, but may not be able to detect weaker puffs having an average flow rate of half or a third of that flow rate. On the other hand, it has been found that for particularly weak puffs, determining the puff based on the heater activation period can provide a more reliable indication of puff detection. Accurate and reliable puff detection is advantageous for multiple functions. In particular, accurate and reliable puff detection allows for determination of a puff count during each smoking session. By way of example, the puff count can be used to identify whether a smoking session can be extended based on whether the number of puffs has been exceeded.

Description

[Technical field]

[0001] The present invention relates to a smoking substitution system, particularly but not exclusively to a smoking substitution system including a device. [Background technology]

[0002] Smoking tobacco is generally regarded as exposing the smoker to potentially harmful substances, which are generally believed to be produced in significant quantities through the burning of tobacco and / or the heat caused by the burning of tobacco, as well as through the constituents of burnt tobacco in the tobacco smoke itself.

[0003] Conventional combustible smoking articles, such as cigarettes, typically include a cylindrical tobacco rod comprising strips of tobacco surrounded by a wrapper, and typically also include a cylindrical filter axially aligned in abutting relationship with the rolled tobacco rod. The filter typically includes a filtration material circumscribed by a plug wrap. The rolled tobacco rod and filter are held together by a rolled strip of tipping paper that circumscribes the entire length of the filter and adjacent portions of the rolled tobacco rod. Conventional cigarettes of this type are used by lighting the end opposite the filter to burn the tobacco rod. A smoker receives mainstream smoke into his or her mouth by drawing on the mouth or filter end of the cigarette.

[0004] The combustion of organic materials such as tobacco is known to produce tar and other potentially harmful by-products. To avoid smoking tobacco, various smoking substitution systems (or "substitute smoking systems") have been proposed.

[0005] Such smoking substitution systems can form part of a nicotine replacement therapy aimed at people wishing to quit smoking and overcome their dependence on nicotine.

[0006] Smoking substitution systems include electronic systems that allow a user to simulate the act of smoking by producing an aerosol (also called "vapor") that is drawn (inhaled) through the mouth into the lungs and then exhaled. The inhaled aerosol typically has nicotine and / or flavorings without or with fewer odors and health risks associated with traditional smoking.

[0007] Generally, smoking substitution systems are intended to provide a substitute for the habitual behavior of smoking while providing users with an experience and satisfaction similar to that experienced with traditional smoking and combustible tobacco products. Some smoking substitution systems use smoking substitution articles (also called "consumables"), which are designed to resemble traditional cigarettes and are cylindrical in shape with a mouthpiece at one end.

[0008] The popularity and use of smoking substitution systems has grown rapidly over the past few years. These systems assist habitual smokers who wish to quit smoking tobacco.

[0009] There are several different categories of smoking proxy systems, each of which utilizes a different smoking proxy approach.

[0010] One approach for smoking substitution systems is the so-called heated tobacco ("HT") approach, in which tobacco (not "e-liquid") is heated or warmed to release vapor. HT is also known as "heat-not-burn" ("HNB"). The tobacco may be leaf tobacco or reconstituted tobacco. The vapor may contain nicotine and / or flavorings. In the HT approach, the intention is that the tobacco is heated without being burned, i.e., the tobacco does not undergo combustion.

[0011] A typical HT smoking substitution system may include a device and a consumable. The consumable may include tobacco material. The device and consumable may be configured to be physically coupled together. In use, heat may be applied to the tobacco material by a heating element of the device, and airflow through the tobacco material causes components in the tobacco material to be released as vapor. The vapor may also be formed from a carrier in the tobacco material (which may include, for example, propylene glycol and / or vegetable glycerin), as well as volatile compounds released from the tobacco. The released vapor may be entrained in the airflow drawn through the tobacco.

[0012] As the vapor passes through the consumable (entrained in the airflow) from the point of evaporation to the outlet of the consumable (e.g., a mouthpiece), the vapor cools and condenses to form an aerosol for inhalation by the user. The aerosol typically contains volatile compounds.

[0013] In HT smoking substitute systems, it is believed that heating, as opposed to burning, tobacco material results in fewer or lower amounts of more harmful compounds typically produced during smoking. As a result, the HT approach can reduce odor and / or health risks that can result through tobacco burning, tobacco combustion, and pyrolytic degradation.

[0014] Improved designs of smoking substitute systems, and in particular HT smoking substitute systems, are needed to enhance the user experience and improve the functionality of HT smoking substitute systems.

[0015] The present disclosure has been devised in view of the above problems. Summary of the Invention

[0016] Most generally, aspects of the invention relate to a non-combustion heated device having a thermostatic heater control, where a puff is determined to have occurred by monitoring the heater activation period for exceeding a threshold value. It has been found that determining a puff from monitoring the heater activation period against a threshold value advantageously allows for detection of weaker puffs that a flow sensor may miss. For example, a flow sensor may be able to detect a puff having an average flow rate of 55 ml / sec, but may not be able to detect weaker puffs having an average flow rate of half or a third of that flow rate. On the other hand, it has been found that for particularly weak puffs, determining a puff based on the heater activation period can provide a more reliable indication of puff detection. Accurate and reliable puff detection is advantageous for multiple functions. In particular, accurate and reliable puff detection allows for the determination of a puff count during each smoking session. By way of example, the puff count can be used to identify whether a smoking session can be extended based on whether the number of puffs is exceeded.

[0017] The thermostatic heater control is configured to turn the heater element on and off to maintain the heater element at a required operating temperature. For example, the required operating temperature may be a band. The band is suitably determined to be suitable for aerosolizing the aerosol-generating substrate. When the heater temperature is detected to be above the upper limit of the band, the thermostatic heater control turns the heater off. That is, the thermostatic heater control prevents power from being provided to the heater element. When the heater element is off, the heater element temperature drops. When the heater element temperature is detected to be below the lower limit of the band, the thermostatic heater control is configured to turn the heater on. That is, the thermostatic heater control provides power to the heater element. When the heater element is on, the heater element heats up and the cycle repeats. The period from when the heater is turned off to when it is turned back on (i.e., the period from when the temperature drops from the upper limit to the lower limit) is called the heater deactivation period. The period from when the heater is turned on to when it is turned back off again (i.e., the period from when the temperature rises from the lower limit to the upper limit) is called the heater activation period. The heater activation period and the subsequent heater deactivation period are called a single thermostatic cycle. Typically, there may be multiple thermostatic cycles per second to maintain the heater temperature at the operating temperature (i.e., the temperature required to generate an aerosol from the aerosol-forming substrate).

[0018] Generally, a smoking session is initiated by inserting a consumable into the device, and the device is activated. For example, a start button can be activated. Once initiated, a thermostatic heater control is configured to activate the heater element to warm the heater element to an operating temperature. That is, the thermostatic heater control is configured to provide power to the heater element. Once the heater element reaches temperature, the thermostatic heater control completes a thermostatic cycle to maintain the heater element temperature within the operating temperature band until the end of the smoking session. After the end of the smoking session (typically based on a predetermined total smoking session time), the thermostatic heater control deactivates the heater element, and the heater element cools down. After the end of the session, once the heater has reached an operating temperature, the user is notified that the session has begun. During these periods, the user inhales on the system to draw air from the consumable and inhale the aerosol generated by the heater element heating the consumable. Each inhalation is referred to as a puff. The user can complete the puffs according to their own preferences. Preferably, the device is configurable to extend the time of a smoking session if the user has not completed the minimum number of puffs during the smoking session. As a result, being able to accurately and repeatedly determine the number of puffs is advantageous in determining when to extend a session. However, other useful features can be or may be incorporated into the aerosol generating device that rely on determining and / or counting puffs.

[0019] According to an exemplary embodiment, the occurrence of a puff is determined by monitoring the activation duration of a thermostat cycle during a session. That is, after the heater warms up and a session is initiated, the thermostat heater control is configured to complete multiple thermostat cycles (i.e., multiple thermostat cycles per second). It has been found that in the absence of external influences (i.e., when the user does not initiate a puff), the heater activation duration of successive thermostat cycles is relatively stable. That is, the heater element temperature naturally adjusts and the heater activation duration is relatively constant. When a puff occurs, the heater element is forced to cool by drawing airflow from the system, thereby extending its heater activation duration after the puff is initiated. That is, the thermostat controller controls the heater element to be activated for longer until the temperature of the heater element exceeds the upper limit of the operating temperature band and the thermostat heater control turns off the heater element. By monitoring the activation duration of each thermostat cycle, a puff can preferably be determined by identifying a heater activation duration that exceeds a threshold, where the threshold may be a predetermined threshold or the threshold may be based on an average of multiple previous activation durations, e.g., a rolling activation duration average.

[0020] As mentioned above, it will be understood that an "aerosol generating device" (or "electronic (e)cigarette") may be a device configured to deliver an aerosol to a user for inhalation by the user. The device may additionally / alternatively be referred to as a "smoking replacement device" if it is intended to be used in place of a conventional combustible smoking article. As used herein, a combustible "smoking article" refers to a cigarette, cigar, pipe, or other article that produces smoke (an aerosol containing solid particles and gases) via heating (typically by combustion and / or pyrolysis) above a pyrolysis temperature. The aerosol generated by the device may include an aerosol having a particle size of 0.2-7 microns, or less than 10 microns, or less than 7 microns. This particle size may be achieved by control of one or more of the heater temperature, the cooling rate as the vapor condenses into the aerosol, and flow characteristics including turbulence and velocity. The generation of the aerosol by the aerosol generating device may be controlled by an input device. The input device may be configured to be activated by a user and may include or take the form of, for example, an actuator (e.g., an activation button) and / or an airflow sensor. In an exemplary embodiment, the aerosol generating apparatus (smoking replacement apparatus) comprises an aerosol generating device (smoking replacement device) and a consumable (aerosol forming article).

[0021] In other words, an exemplary embodiment provides an aerosol generating device comprising a heater element, a temperature sensor, and a control system including a thermostatic heater control. The control system is configured to initiate a smoking session by operating the thermostatic heater control to activate the heater element. The thermostatic heater control is configured to activate and deactivate the heater element during a thermostatic cycle based on an output of the temperature sensor to maintain the heater element temperature between an operating temperature band. The control system is configured to monitor the activation period of each thermostatic cycle and determine that a puff has been initiated based on determining that the activation period has exceeded a threshold value.

[0022] Optional features are described below, which may be applied alone or in any combination with any aspect.

[0023] In an exemplary embodiment, the heater element is preferably a heater rod, although other heater elements are envisioned, such as blades, coils, or electromagnetic induction systems operated by thermostatic control (i.e., on / off adjustment to maintain operating temperature).

[0024] In an exemplary embodiment, a temperature sensor monitors the temperature of the heating element. For example, the temperature sensor can be fixed directly to the heating element. In some embodiments, the temperature sensor can be a resistive track formed on the heating element from which the temperature can be derived by a change in resistance. The output of the temperature sensor is used by a thermostatic heater control to determine when the temperature of the heating element is above or below an operating temperature band.

[0025] In an exemplary embodiment, the thermostatic heater control and the control system may be the same or separate units. Furthermore, the control system may include a controller and memory necessary to complete one or more functions of the device. Here, the functions may include additional functions of the device as known in the art. In particular, the control system may include a counting function for counting the number of determined puffs. Here, the counting function may be reset at the end of the smoking session. However, it is envisioned that there may be functions of the device in which puff counts for different periods of time are useful. The control system may preferably use the puff count number. For example, the control system may determine whether to extend the smoking session period based on the puff count number. The control system may additionally or alternatively use the puff count number or puff detection to control other functions of the device or to transmit information to an external device.

[0026] In some exemplary embodiments, the control system is configured to determine a puff when the activation period exceeds a predetermined threshold. That is, the activation period (length of on-time of the heater element) over which a puff is determined may be pre-determined in the control system as a fixed length. However, in a preferred embodiment, the threshold for the activation period above which a puff is determined may be based on an average of the activation periods of a number of previous thermostat cycles, where the number of consecutive thermostat cycles may be a fixed number of previous cycles (e.g., a rolling average). In an exemplary embodiment in which the threshold is based on an average of previous thermostat cycles, the threshold may be determined based on a percentage increase (i.e., a puff is determined when the activation period is 10% greater than the average) or a fixed offset (i.e., a puff is determined when the activation period is 100 milliseconds longer than the average). In an exemplary embodiment in which the threshold is determined by a percentage increase from an average of previous activation periods, the percentage increase may be greater than 10%, or greater than 20%, or greater than 30%, or greater than 40%. In an exemplary embodiment in which the threshold is determined by a fixed offset from an average of previous activation periods, the fixed offset may be greater than 100 ms, or greater than 150 ms, or greater than 200 ms.

[0027] The aerosol generating device (i.e., the device) may comprise an elongated body. An end of the elongated body may be configured to engage an aerosol-forming article. For example, the body may be configured to engage a heated tobacco (HT) consumable (or a heat-not-burn (HNB) consumable). The terms "heat-not-burn" and "heat-not-burn" are used interchangeably herein to describe a type of consumable that is heated rather than combusted (or are used interchangeably to describe a device for use with such a consumable). The device may include a cavity configured to receive (i.e., engage) at least a portion of the consumable. The aerosol-forming article may be of a type that includes an aerosol former (e.g., carried by an aerosol-forming substrate).

[0028] The device may include a heater for heating the aerosol-forming article. The heater may include a heating element, which may be in the form of a rod extending from a body of the device. The heating element may extend from an end of the body configured to engage the aerosol-forming article.

[0029] The heater (and thus the heating element) may be rigidly attached to the body. The heating element may be elongated to define a longitudinal axis and may, for example, have a substantially circular transverse profile (i.e., transverse to the longitudinal axis of the heating element) (i.e., the heating element may be generally cylindrical). Alternatively, the heating element may have a rectangular transverse profile (i.e., the heater may be a "blade heater"). Alternatively, the heating element may be shaped like a tube (i.e., the heater may be a "tubular heater"). The heating element may take other shapes (e.g., the heating element may have an oval transverse profile). The shape and / or size (e.g., diameter) of the transverse profile of the heating element may be generally consistent throughout (or substantially throughout) the length of the heating element.

[0030] The heating element may be from 15mm to 25mm long, such as from 18mm to 20mm long, for example about 19mm long. The heating element may have a diameter of from 1.5mm to 2.5mm, such as a diameter of from 2mm to 2.3mm, for example a diameter of about 2.15mm.

[0031] The heating element may be formed from a ceramic. The heating element may include a core (e.g., a ceramic core) comprising Al2O3. The heating element core may have a diameter of 1.8 mm to 2.1 mm, such as 1.9 mm to 2 mm. The heating element may include an outer layer (e.g., an outer ceramic layer) comprising Al2O3. The outer layer may have a thickness of 160 μm to 220 μm, such as 170 μm to 190 μm, such as about 180 μm. The heating element may include a heating track, which may extend longitudinally along the heating element. The heating track may be sandwiched between the outer layer and the core of the heating element. The heating track may include tungsten and / or rhenium. The heating track may have a thickness of about 20 μm.

[0032] The heating element may be located in the cavity (of the device) and may extend from the interior base of the cavity toward the opening of the cavity (e.g., along the longitudinal axis). The length of the heating element (i.e., the length along the longitudinal axis of the heater) may be less than the depth of the cavity. Thus, the heating element may extend over only a portion of the length of the cavity. That is, the heating element may not extend through (or beyond) the opening of the cavity.

[0033] The heating element may be configured to be inserted into the aerosol-forming article (e.g., an HT consumable) when the aerosol-forming article is received in the cavity. In that regard, a distal end of the heating element (i.e., distal from a base of the heating element attached to the device) may include a tapered portion, which may facilitate insertion of the heating element into the aerosol-forming article. When the aerosol-forming article is received in the cavity, the heating element may fully penetrate the aerosol-forming article. That is, the entire length or substantially the entire length of the heating element may be received in the aerosol-forming article.

[0034] The heating element may have a length less than or substantially the same as the axial length of the aerosol-forming substrate forming part of the aerosol-forming article (e.g., HT consumable). Thus, when such an aerosol-forming article is engaged with a device, the heating element may penetrate only the aerosol-forming substrate and not other components of the aerosol-forming article. The heating element may penetrate the aerosol-forming substrate over substantially the entire axial length of the aerosol-forming substrate of the aerosol-forming article. Thus, when penetrated by the heating element, heat may be transferred from the heating element (e.g., its outer circumferential surface) to the surrounding aerosol-forming substrate. That is, heat may be transferred radially outward (in the case of a cylindrical heating element) or, for example, radially inward (in the case of a tubular heater).

[0035] When the heater is a tubular heater, the heating element of the tubular heater can surround at least a portion of the cavity. When a portion of the aerosol-forming article is received in the cavity, the heating element can surround (i.e. heat) a portion of the aerosol-forming article. In particular, the heating element can surround an aerosol-forming substrate of the aerosol-forming article. That is, when the aerosol-forming article is engaged with the device, the aerosol-forming substrate of the aerosol-forming article can be located adjacent to an inner surface of the (tubular) heating element. When the heating element is activated, heat can be transferred radially inward from the inner surface of the heating element to heat the aerosol-forming substrate.

[0036] The cavity may include a (e.g., circumferential) wall (or walls) and the (tubular) heating element may extend around at least a portion of this wall. In this manner, the wall may be located between an inner surface of the heating element and an outer surface of the aerosol-forming article. The wall (or walls) of the cavity may be formed from a thermally conductive material (e.g., metal) to allow for heat conduction from the heating element to the aerosol-forming article. Thus, heat may be conducted from the heating element through the cavity wall (or walls) to an aerosol-forming substrate of the aerosol-forming article received in the cavity.

[0037] In some embodiments, the device can include a cap disposed on an end of the body configured to engage the aerosol-forming article. If the device includes a heater having a heating element, the cap can at least partially surround the heating element. The cap can be movable between an open position, in which access to the heating element is provided, and a closed position, in which the cap at least partially surrounds the heating element. The cap can be slidably engaged with the body of the device and can be slidable between the open and closed positions.

[0038] The cap can define at least a portion of the cavity of the device. That is, the cavity can be completely defined by the cap, or the cap and the body can each define a portion of the cavity. If the cap completely defines the cavity, the cap can include an opening for receiving the heating element into the cavity (when the cap is in the closed position). The cap can include an opening to the cavity. The opening can be configured to receive at least a portion of the aerosol-forming article. That is, the aerosol-forming article can be inserted into the cavity (engaged to the device) through the opening.

[0039] The cap may be configured such that when the aerosol-forming article is engaged with the device (e.g., received in the cavity), only a portion of the aerosol-forming article is received in the cavity. That is, a portion of the aerosol-forming article (not received in the cavity) may protrude from the opening (i.e., extend beyond the opening). This (protruding) portion of the aerosol-forming article may be an end (e.g., a mouth end) of the aerosol-forming article, which may be received in the mouth of a user for the purpose of inhaling an aerosol formed by the device.

[0040] The device may include a power source or may be connectable to a power source (e.g., a power source separate from the device). The power source may be electrically connectable to the heater. In that regard, changing (e.g., toggling) the electrical connection of the power source to the heater may affect the state of the heater. For example, toggling the electrical connection of the power source to the heater may toggle the heater between an on state and an off state. The power source may be a power store. For example, the power source may be a battery or a rechargeable battery (e.g., a lithium ion battery).

[0041] The device may include an input connection (e.g., a USB port, a Micro USB port, a USB-C port, etc.). The input connection may be configured to connect to an external power source, such as a power outlet. The input connection may in some cases be used as a substitute for an internal power source (e.g., a battery or a rechargeable battery). That is, the input connection may be electrically connectable to a heater (to provide power to the heater). Thus, in some forms, the input connection may form at least a portion of the power source of the device.

[0042] If the power source includes a rechargeable power source (such as a rechargeable battery), the input connection may be used to charge and recharge the power source.

[0043] The device may include a user interface (UI). In some embodiments, the UI may include input means for receiving operational commands from a user. The input means of the UI may allow a user to control at least one aspect of the operation of the device. In some embodiments, the input means may include a power button for switching the device between an on state and an off state.

[0044] In some embodiments, the UI may additionally or alternatively include an output means for communicating information to a user. In some embodiments, the output means may include a light for indicating a status of the device (and / or the aerosol-forming article) to the user. The status of the device (and / or the aerosol-forming article) indicated to the user may include a status indicative of the operation of the heater. For example, the status may include whether the heater is in an off state or an on state. In some embodiments, the UI unit may include at least one of a button, a display, a touch screen, a switch, a light, and the like. For example, the output means may include one or more (e.g., two, three, four, etc.) light emitting diodes ("LEDs"), which may be located on the body of the device.

[0045] The device may further include a puff sensor (e.g., an airflow sensor), which forms part of the input means of the UI. The puff sensor may be configured to detect when a user inhales at an end (i.e., the distal (oral) end) of the aerosol-forming article. The puff sensor may be, for example, a pressure sensor or a microphone. The puff sensor may be configured to generate a signal indicative of a puff state. The signal may indicate when a user has inhaled (aerosol from the aerosol-forming article), for example in the form of a binary signal. Alternatively or additionally, the signal may indicate a characteristic of the inhalation (e.g., flow rate of the inhalation, length of time of the inhalation, etc.).

[0046] The device may include or be connectable to a controller, which may be configured to control at least one function of the device. The controller may include a microcontroller, which may be mounted, for example, on a printed circuit board (PCB). The controller may also include a memory, for example a non-volatile memory. The memory may include instructions, which, when executed, cause the controller to perform certain tasks or steps of a method. If the device includes an input connection, the controller may be connected to the input connection.

[0047] The controller is configured to control the operation of the heater (and, e.g., the heating element). Thus, the controller may be configured to control the evaporation of an aerosol-forming portion of an aerosol-forming article engaged with the device. The controller may be configured to control the voltage applied by the power supply to the heater. For example, the controller may be configured to toggle between applying the full output voltage (of the power supply) to the heater and applying no voltage to the heater. Alternatively, or in addition, the control unit may implement a more complex heater control protocol.

[0048] The device may further include a voltage regulator for regulating the output voltage provided by the power supply to form a regulated voltage, which may then be applied to the heater.

[0049] In some embodiments, where the device includes a UI, the controller may be operatively connected to one or more components of the UI. The controller may be configured to receive command signals from an input means of the UI. The controller may be configured to control the heater in response to the command signals. For example, the controller may be configured to receive "on" and "off" command signals from the UI and in response thereto can control the heater to a corresponding on or off state.

[0050] The controller may be configured to send output signals to components of the UI. The UI may be configured to communicate information to a user via the output means in response to such output signals (received from the controller). For example, if the device includes one or more LEDs, the LEDs may be operably connected to the controller. The controller may thus be configured to control the illumination of the LEDs (e.g., in response to the output signals). For example, the controller may be configured to control the illumination of the LEDs according to a state of a heater (e.g., on or off).

[0051] If the device includes a sensor (e.g., a puff / airflow sensor), the controller may be operatively connected to the sensor. The controller may be configured to receive a signal from the sensor (e.g., indicative of a state of the device and / or an engaged aerosol-forming article). The controller may be configured to control the heater, or a form of the output means, based on the signal from the sensor.

[0052] The device may include a wireless interface configured to communicate wirelessly (e.g., via Bluetooth (e.g., a Bluetooth low energy connection) or WiFi) with an external device. Similarly, the input connection may be configured to make a wired connection to an external device to provide communication between the device and the external device.

[0053] The external device may be a mobile device. For example, the external device may be a smartphone, a tablet, a smart watch, or a smart car. The external device (e.g., a mobile device) may have an application (e.g., an app) installed on it. The application may facilitate communication between the device and the external device via a wired or wireless connection.

[0054] The wireless or wired interface may be configured to communicate signals between the external device and the controller of the device. In this regard, the controller may control the configuration of the device in response to signals received from the external device. Alternatively, or in addition, the external device may respond to signals received from the device (e.g., the controller of the device).

[0055] In an exemplary embodiment, a smoking replacement system is provided, comprising a smoking replacement device according to the above-mentioned embodiment and an aerosol-forming article. The aerosol-forming article may comprise an aerosol-forming substrate at an upper end of the aerosol-forming article. The article may be in the form of a smoking replacement article, such as a heated tobacco (HT) consumable (also known as a heat-not-burn (HNB) consumable).

[0056] All optional features of the disclosure described above in the context of the previous embodiment apply equally to the further embodiment. All optional features of the detection element and / or the at least one deformable wall described above in the context of the previous embodiment also apply equally to the further embodiment.

[0057] As used herein, the terms "upstream" and "downstream" are intended to refer to the direction of vapor / aerosol flow, i.e., the downstream end of the article / consumable is the mouth end or outlet where the aerosol exits the consumable for inhalation by the user. The upstream end of the article / consumable is the end opposite the downstream end.

[0058] The aerosol-forming substrate is capable of being heated to release at least one volatile compound capable of forming an aerosol. The aerosol-forming substrate may be located at the upstream end of the article / consumable.

[0059] To generate an aerosol, the aerosol-forming substrate comprises at least one volatile compound, which is intended to be vaporized / aerosolized and can provide a recreational and / or medicinal effect to the user when inhaled. Suitable chemically and / or physiologically active volatile compounds include the group consisting of nicotine, cocaine, caffeine, opiates and opioids, cathines and cathinones, kavalactones, mysticin, beta-carboline alkaloids, salvinorin A, together with any combinations, functional equivalents, and / or synthetic substitutes of the above.

[0060] The aerosol-forming substrate may include plant material. The plant materials include Amaranthus dubius, Arctostaphylos uva-ursi (bearberry), Argemone mexicana, Amica, Artemisia vulgaris, Yellow Tees, Galea zacatechichi, Canavalia maritima (Baybean), Cecropia mexicana (Guamura), Cestrum noctumum, Cynoglossum virginianum (wild comfrey), Cytisus scoparius, damiana, Entada rheedii, Eschscholzia califomica (Papaver somniferum), Fittonia albivenis, Hippobroma longiflora, Humulus japonica (Japanese knotweed), Humulus lupulus (hops), Lactuca virosa (wild lettuce), Laggera alata, Leonotis leonurus, Leonurus cardiaca (Broomstick), Leonurus sibiricus (Broomstick), Lobelia cardinalis, Lobelia inflata (Lobelia), Lobelia siphilitica, Nepeta cataria (Catnip), Nicotiana spp. (Tobacco), Nymphaea alba (Water Lily), Nymphaea caerulea (Water Lily), Opium poppy, Passiflora incamata (Passion Flower), Pedicularis densiflora (Indian Warrior), Pedicularis groenlandica (Elephant's Head), Salvia divinorum, Salvia dorrii (Tobacco Sage), Salvia spp. (Sage), Scutellaria galericulata, Scutellaria lateriflora, Scutellarianana, Scutellaria spp. (Skullcap), Sida acuta (Sida rhombifolia), Silene capensis, Syzygium aromaticum (Clove), Tagetes lucida (Mint marigold), Tarchonanthus camphoratus, Tumera diffusa (Damiana), Mullein spp. (Mullein), Zamia latifolia (Maconha Brava), together with any combination, functional equivalent, and / or synthetic alternative of the above.

[0061] The plant material may be tobacco. Any type of tobacco may be used, including, but not limited to, flue-cured, burley, Maryland, dark air-cured, oriental, dark flue-cured, perique, and rustica. This also includes blends of the aforementioned tobaccos.

[0062] Tobacco can include one or more of leaf tobacco, stem tobacco, tobacco powder, tobacco dust, tobacco derivatives, expanded tobacco, homogenized tobacco, cut tobacco, extruded tobacco, cut rag tobacco, and / or reconstituted tobacco (e.g., slurry recon or paper recon).

[0063] The aerosol-forming substrate may comprise a collecting sheet of homogeneous (eg paper / slurry recon) tobacco, or a collecting strip / strip formed from such a sheet.

[0064] The aerosol-forming substrate may include one or more additives selected from humectants, flavoring agents, bulking agents, aqueous / non-aqueous solvents, and binders.

[0065] The flavourings may be provided in solid or liquid form. The flavourings may include menthol, licorice, chocolate, fruit flavours (including, for example, citrus, cherry, etc.), vanilla, spices (e.g., ginger, cinnamon), and tobacco flavours. The flavourings may be uniformly dispersed throughout the aerosol-forming substrate or may be provided at discrete locations and / or varying concentrations throughout the aerosol-forming substrate.

[0066] The aerosol-forming substrate may be formed in a substantially cylindrical shape such that the article / consumable resembles a conventional cigarette. The aerosol-forming substrate may have a diameter of 5 to 10 mm, such as 6 to 9 mm or 6 to 8 mm, for example about 7 mm. The aerosol-forming substrate may have an axial length of 10 to 15 mm, for example 11 to 14 mm, such as about 12 or 13 mm.

[0067] The article / consumable may include at least one filter element. A terminal filter element may be located at the downstream / mouth end of the article / consumable.

[0068] The, or at least one, filter element (e.g., an end filter element) may be constructed from cellulose acetate or polypropylene tow. The, or at least one, filter element (e.g., an end filter element) may be constructed from activated carbon. The, or at least one, filter element (e.g., an end element) may be constructed from paper. The, or each, filter element may be at least partially (e.g., entirely) circumscribed by a plug wrap, e.g., a paper plug wrap.

[0069] A terminal filter element (the downstream end of the article / consumable) can be joined to an upstream element to form the article / consumable by a circumscribing tipping layer, e.g., a tipping paper layer. The tipping paper can have an axial length greater than the axial length of the terminal filter element, such that the tipping paper completely circumscribing the terminal filter element and the wrap layer surrounding any adjacent upstream elements.

[0070] In some embodiments, the article / consumable may include an aerosol cooling element adapted to cool the aerosol generated (by heat exchange) from the aerosol-forming substrate before it is inhaled by the user.

[0071] The article / consumable may include a spacer element that defines a space or cavity between the aerosol-forming substrate and the downstream end of the consumable. The spacer element may include a paper tube. The spacer element may be circumscribed by a (paper) wrap layer.

[0072] As will be appreciated, the articles and systems of the exemplary embodiments and aspects can be used to generate an aerosol by operatively connecting a consumable and a device and inhaling to draw air from the consumable. When inhalation is completed while the heater is at its operating temperature, the heater generates an aerosol from the consumable (i.e., the aerosol-generating substrate), and the aerosol is entrained in the airflow for inhalation by the user. It will be further appreciated that the method can include any number of additional method steps known in the art, whether described herein or not. Most generally, the method includes controlling the aerosol generating device to activate and deactivate the heater element and maintain the temperature of the heating element within the operating temperature. The method is characterized by determining that the activation period of the heater element has exceeded a threshold value. As described herein, determining a puff based on the activation period exceeding a threshold value can be a more reliable and accurate way of determining a puff than conventional methods using air flow sensors. Thus, in an exemplary embodiment, the method includes determining that a puff has begun based on determining that the activation period of the heater has exceeded a threshold value.

[0073] Exemplary embodiments may preferably include calculating an average of the preceding activation periods and determining the threshold value based on the calculated average. The average of the preceding activation periods may be a fixed number of activation periods (i.e., a rolling average).

[0074] The method may include counting the number of puff initiated determinations during a smoking session and extending the smoking session if a minimum count is not reached during the smoking session, i.e., if a user does not take a minimum number of inhalations during a smoking session of fixed length, the smoking session may be extended by entering a smoking session extension period.

[0075] As will be appreciated, example methods may include methods of using or operating or controlling a device or system according to example embodiments and aspects described herein.

[0076] An exemplary method may be a method of operating a non-combustion heated device, for example, that preferably includes determining a position of an occlusion for covering a cavity of the device in which an aerosol generating consumable (202) is received during use, and controlling a heater of the device based on the determined position of the occlusion.

[0077] The method may include determining the position of the closure by a sensor associated with the controller, and the controller preferably deactivates the heater based on a signal received from the sensor when the closure is in a first position covering a cavity within the device.

[0078] Example embodiments and aspects include combinations of the described aspects and preferred features unless such combinations are expressly impermissible or expressly avoided.

[0079] Those skilled in the art will recognize that, unless mutually exclusive, a feature or parameter described in connection with any one of the above embodiments may also be applied to any other embodiment. Further, unless mutually exclusive, any feature or parameter described herein may be applied to any embodiment and / or may be combined with any other feature or parameter described herein. [Brief description of the drawings]

[0080] Embodiments illustrating the principles of the present disclosure will now be described in more detail, with reference to the accompanying drawings, so that the illustrative embodiments may be understood and further aspects and features thereof may be realized.

[0081] [Figure 1A] FIG. 1 is a schematic diagram of a smoking substitution system. [Figure 1B] FIG. 1B is a schematic diagram of a variation of the smoking substitution system of FIG. 1A. [Figure 2A] FIG. 1 is a front view of a first embodiment of a smoking substitution system with a consumable engaged with the device. [Figure 2B] FIG. 1 is a front view of a first embodiment of a smoking substitution system, with the consumables detached from the device. [Figure 2C] 1 is a cross-sectional view of a consumable of a first embodiment of a smoking substitution system. FIG. [Figure 2D] FIG. 2 is a detailed view of the end of the device of the first embodiment of the smoking substitution system. [Figure 2E] FIG. 1 is a cross-sectional view of a first embodiment of an alternative smoking system. [Diagram 3] 1 is a representative graph showing a thermostatic heater control, in which the temperature of the heating element is plotted against periods of heater activation and deactivation during a smoking session. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0082] Aspects and embodiments of the present disclosure are discussed below with reference to the accompanying figures. Further aspects and embodiments will be apparent to those skilled in the art. All documents mentioned in this text are incorporated herein by reference.

[0083] 1A is a schematic diagram providing a general overview of a smoking substitution system 100. The system 100 includes a substitute smoking device 101 and an aerosol-forming article in the form of a consumable 102, which includes an aerosol former 103. The system is configured to vaporize the aerosol former 103 by heating the aerosol former 103 (forming a vapor / aerosol for inhalation by a user).

[0084] In the system shown, the heater 104 forms part of the consumable 102 and is configured to heat the aerosol formation body 103. In this variation, the heater 104 is electrically connectable to a power source 105, for example when the consumable 102 is engaged with the device 101. The heat from the heater 104 causes the aerosol formation body 103 to evaporate, producing a vapor. The vapor then condenses to form an aerosol, which is ultimately inhaled by the user.

[0085] The system 100 further includes a power source 105, which forms part of the device 101. In other embodiments, the power source 105 may be located external to the device 101 (but connectable to the device 101). The power source 105 may be electrically connectable to the heater 104 such that the power source 105 can provide power to the heater 104 (i.e., for heating the aerosol formation body 103). Thus, controlling the electrical connection of the power source 105 to the heater 104 provides control of the state of the heater 104. The power source 105 may be a power store, such as a battery or a rechargeable battery (e.g., a lithium ion battery).

[0086] The system 100 further includes an I / O module that includes a connector 106 (e.g., in the form of a USB port, a Micro USB port, a USB-C port, etc.). The connector 106 is configured to connect to an external power source, e.g., a power outlet. The connector 106 may be used as a substitute for the power source 105; that is, the connector 106 may be electrically connectable to the heater 104 to provide electricity to the heater 104. In such an embodiment, the device may not include a power source, and instead the power source of the system may include the connector 106 and the external power source (with the connector 106 providing the electrical connection).

[0087] In some embodiments, the connector 106 may be used to charge and recharge the power source 105 if the power source 105 includes a rechargeable battery.

[0088] The system 100 also includes a user interface (UI) 107. Although not shown, the UI 107 may include input means for receiving commands from a user. The input means of the UI 107 allows a user to control at least one aspect of the operation of the system 100. The input means may be in the form of, for example, buttons, a touch screen, switches, a microphone, etc.

[0089] The UI 107 also includes output means for communicating information to the user, which may include, for example, lights (e.g., LEDs), a display screen, a speaker, a vibration generator, etc.

[0090] The system 100 further includes a controller 108 configured to control at least one function of the device 101. In the embodiment shown, the controller 108 is a component of the device 101, but in other embodiments the controller 108 may be separate from (but connectable to) the device 101. The controller 108 may be configured to control the operation of the heater 104, for example, to control the voltage applied to the heater 104 from the power supply 105. The controller 108 may be configured to toggle the supply of power to the heater 104 between an on state, in which the full output voltage of the power supply 105 is applied to the heater 104, and an off state, in which no voltage is applied to the heater 104.

[0091] Although not shown, the system 100 may also include a voltage regulator for regulating the output voltage from the power supply 105 to form a regulated voltage. This regulated voltage may then be applied to the heater 104.

[0092] In addition to being connected to the heater 104, the controller 108 is operatively connected to the UI 107. Thus, the controller 108 can receive input signals from the input means of the UI 107. Similarly, the controller 108 can transmit output signals to the UI 107. In response, the output means of the UI 107 can convey information to a user based on the output signals. The controller also comprises a memory 109, which is a non-volatile memory. The memory 109 includes instructions that, when implemented, cause the controller to perform certain tasks or steps of a method.

[0093] Figure IB is a schematic diagram illustrating a variation of the system 100 of Figure IA. In the system 100' of Figure IB, the heater 104 forms part of the consumable 102 rather than the device 101. In this variation, the heater 104 is electrically connectable to a power source 105, for example when the consumable 102 is engaged with the device 101.

[0094] 1A and 1B can each be implemented as one of two broad system categories: a heated tobacco (HT) system or an e-cigarette system according to an exemplary embodiment, each of which is described below.

[0095] Figures 2A and 2B show a heated tobacco (HT) smoking replacement system 200. System 200 is an example of system 100, 100' described in relation to Figures 1A or 1B. System 200 includes a heat-not-burn (HNB) device 201 and a HT consumable 202. The description of Figures 1A and 1B above is also applicable to system 200 of Figures 2A and 2B and therefore will not be repeated.

[0096] The device 201 and the consumable 202 are configured such that the consumable 202 can be engaged with the device 201. Figure 2A shows the device 201 and the consumable 202 in an engaged state, and Figure 2B shows the device 201 and the consumable 202 in a detached state.

[0097] The device 201 includes a body 209 and a cap 210. In use, the cap 210 is engaged at an end of the body 209. Although not apparent from these views, the cap 210 is movable relative to the body 209. In particular, the cap 210 is slidable and can slide along the longitudinal axis of the body 209.

[0098] The device 201 includes output means (forming part of the UI of the device 201) in the form of a plurality of light emitting diodes (LEDs) 211 arranged linearly on an outer surface of the body 209 of the device 201 along a longitudinal axis of the device 201. A button 212 is also arranged on the outer surface of the body 209 of the device 201 and is spaced axially (i.e. along the longitudinal axis) from the plurality of LEDs 211.

[0099] 2C shows a detailed cross-sectional view of the consumable 202 of the system 200. The consumable 202 generally resembles a cigarette. In that respect, the consumable 202 has a generally cylindrical shape with a diameter of 7 mm and an axial length of 70 mm. The consumable 202 includes an aerosol-forming substrate 213, a terminal filter element 214, an upstream filter element 215, and a spacer element 216. In other embodiments, the consumable can further include a cooling element. The cooling element can exchange heat with the vapor formed by the aerosol-forming substrate 213 to cool the vapor to facilitate condensation of the vapor.

[0100] The aerosol-forming substrate 213 is substantially cylindrical, is located at the upstream end 217 of the consumable 202, and comprises the aerosol former of the system 200. At that point, the aerosol-forming substrate 213 is configured to be heated by the device 201 to emit a vapor. The emitted vapor is then entrained in an airflow passing through the aerosol-forming substrate 213. The airflow is created by the action of a user inhaling at the downstream end 218 (i.e., the distal or oral end) of the consumable 202.

[0101] In this embodiment, the aerosol-forming substrate 213 includes a tobacco material, which may include, for example, any suitable part of a tobacco plant (e.g., leaves, stems, roots, husks, seeds, and flowers). The tobacco may include one or more of leaf tobacco, stem tobacco, tobacco powder, tobacco dust, tobacco derivatives, expanded tobacco, homogenized tobacco, cut tobacco, extruded tobacco, cut rag tobacco, and / or reconstituted tobacco (e.g., slurry recon or paper recon). For example, the aerosol-forming substrate 213 may include a collecting sheet of homogenous (e.g., paper / slurry recon) tobacco, or collecting strips / strips formed from such a sheet.

[0102] To generate an aerosol, the aerosol-forming substrate 213 includes at least one volatile compound that is intended to be evaporated / aerosolized and that, when inhaled, can provide a recreational and / or medicinal effect to the user. The aerosol-forming substrate 213 can further include one or more additives. For example, such additives can be in the form of humectants (e.g., propylene glycol and / or vegetable glycerin), flavorings, fillers, aqueous / non-aqueous solvents, and / or binders.

[0103] The terminal filter element 214 is also substantially cylindrical and is located at the downstream end 218 of the consumable 202, downstream of the aerosol-forming substrate 213. The terminal filter element 214 is in the form of a hollow filter element with holes 219 (e.g. for air flow) formed therein. The holes 219 have a diameter of 2 mm. The terminal filter element 214 is formed from a porous (e.g. monoacetate) filter material. As mentioned above, the downstream end 218 of the consumable 202 (i.e. where the terminal filter 214 is located) forms the mouthpiece portion of the consumable 202 into which the user inhales. Airflow is drawn from the upstream end 217, through the components of the consumable 202, and out the downstream end 218. The airflow is driven by the user inhaling at the downstream end 218 (i.e. the mouthpiece portion) of the consumable 202.

[0104] The upstream filter element 215 is located axially adjacent to the aerosol-forming substrate 213, between the aerosol-forming substrate 213 and the terminal filter element 214. Like the terminal filter 214, the upstream filter element 215 is in the form of a hollow filter element, with holes 220 extending axially therethrough. In this manner, the upstream filter 215 can act as an airflow restrictor. The upstream filter element 215 is formed from a porous (e.g., monoacetate) filter material. The holes 220 of the upstream filter element 215 have a larger diameter (3 mm) than the terminal filter element 214.

[0105] Spacer 216 is in the form of a paper tube and defines a cavity or chamber between upstream filter element 215 and terminal filter element 214. Spacer 216 acts to allow both cooling and mixing of the vapor / aerosol from aerosol-forming substrate 213. The spacer has an outer diameter of 7 mm and an axial length of 14 mm.

[0106] Although it is not apparent from these figures, the aerosol-forming substrate 213, the upstream filter 215, and the spacer 216 are circumscribed by a paper wrap layer. The terminal filter 214 is circumscribed by a tip layer, which also circumscribes a portion of the paper wrap layer (to connect the terminal filter 214 to the remaining components of the consumable 202). The upstream filter 215 and the terminal filter 214 are circumscribed by a further wrap layer in the form of a plug wrap.

[0107] Referring again now to the device 201, FIG. 2D shows a detailed view of an end of the device 201 configured to engage the consumable 202. The cap 210 of the device 201 includes an opening 221 to an internal cavity 222 defined by the cap 210 (as is more evident from FIG. 2D). The opening 221 and the cavity 222 are formed to receive at least a portion of the consumable 202. When the consumable 202 is engaged with the device 201, a portion of the consumable 202 is received through the opening 221 and into the cavity 222. After engagement (see FIG. 2B), the downstream end 218 of the consumable 202 protrudes from the opening 221 and thus from the device 201. The opening 221 includes laterally disposed notches 226. When the consumable 202 is received in the opening 221, these notches 226 remain open and can be used, for example, to hold a cover to cover the end of the device 201.

[0108] 2E shows a cross-sectional view of a central longitudinal plane through the device 201. The device 201 is shown with a consumable 202 engaged.

[0109] The device 201 includes a heater 204, which includes a heating element 223. The heater 204 forms part of the body 209 of the device 201 and is rigidly attached to the body 209. In the embodiment shown, the heater 204 is a rod heater and the heating element 223 has a circular transverse profile. In other embodiments, the heater may be in the form of a blade heater (e.g., a heating element having a rectangular transverse profile) or a tubular heater (e.g., a heating element having a tubular shape).

[0110] The heating element 223 of the heater 204 protrudes from the interior base of the cavity 222 along the longitudinal axis towards the opening 221. As is evident from this view, the length of the heating element (i.e., the length along the longitudinal axis) is less than the depth of the cavity 222. In this manner, the heating element 223 does not protrude from or extend beyond the opening 221.

[0111] When the consumable 202 is received in the cavity 222 (as shown in FIG. 2E ), the heating element 223 penetrates the aerosol-forming substrate 213 of the consumable 202. In particular, when inserted, the heating element 223 extends across substantially the entire axial length of the aerosol-forming substrate 213. Thus, when the heater 204 is activated, heat is transferred radially from the outer circumferential surface of the heating element 223 to the aerosol-forming substrate 213.

[0112] The device 201 further includes an electronics cavity 224. Located in the electronics cavity 224 is a power source in the form of a rechargeable battery 205 (a lithium ion battery).

[0113] The device 201 includes a connector (i.e., forming part of the IO module of the device 201) in the form of a USB port 206. For example, the connector may alternatively be, for example, a micro USB port or a USB-C port. The USB port 206 may be used to recharge the rechargeable battery 205.

[0114] The device 201 includes a controller (not shown) located in the electronics cavity 224. The controller includes a microcontroller mounted on a printed circuit board (PCB). The USB port 206 is also connected to the controller 208 (i.e., connected to the PCB and to the microcontroller).

[0115] The controller 208 is configured to control at least one function of the device 201. For example, the controller 208 is configured to control the operation of the heater 204. Such control of the operation of the heater 204 may be achieved by the controller toggling an electrical connection of the rechargeable battery 205 to the heater 204. For example, the controller 208 is configured to control the heater 204 in response to a user pressing a button 212. Pressing the button 212 may cause the controller to enable a voltage (from the rechargeable battery 205) to be applied to the heater 204 (heating the heating element 223).

[0116] The controller is also configured to control the LEDs 211 in response to a (e.g., detected) state of the device 201 or the consumable 202. For example, the controller may control the LEDs to indicate whether the device 201 is in an on or off state (e.g., one or more of the LEDs may be illuminated by the controller when the device is in an on state).

[0117] The device 201 includes a further input means (i.e., in addition to the button 212) in the form of a puff sensor 225. The puff sensor 225 is configured to detect when a user draws (i.e., inhales) on the downstream end 218 of the consumable 202. The puff sensor 225 may be in the form of a pressure sensor, a flow meter, or a microphone, for example. The puff sensor 225 is operatively connected to the controller 208 within the electronics cavity 224 such that a signal from the puff sensor 225 indicative of a puff state (i.e., inhalation or not inhalation) forms an input to (and may therefore be responded to by) the controller 208.

[0118] As will be appreciated, the heating element 223 (or heater element) of the device 201 (or aerosol generating device) is controlled by the controller 208 (or control system) to be activated and heat the consumable. In an exemplary embodiment, the control system comprises a thermostatic heater control. Thermostatic heater controls are known in the art and operate by modulating the power supplied to the heater element between on and off. As a result, as shown in FIG. 3, when the device is operated to start a smoking session (Sstart), the thermostatic heater control activates the heater (i.e. provides power to the heater at an "on level"). The heater element enters a warm-up period, during which the heater element warms up to a temperature suitable for generating aerosol from the consumable. During the warm-up period, the heater element is activated until the heater temperature exceeds the upper limit (Tmax) of the operating temperature band. The device preferably comprises a temperature sensor (not shown) for monitoring the temperature of the heater element. For example, the temperature sensor can be attached directly to the outer surface of the heater element. The output of the temperature sensor is preferably used by a thermostatic heater control to determine when an upper limit Tmax has been exceeded.

[0119] When the thermostatic heater controller determines that the upper temperature limit has been exceeded, the warm-up period ends and the heater element is deactivated. That is, the thermostatic heater controller determines that the heating element has reached the upper temperature limit and turns off the power to the heater element. The device is preferably configured to provide an alert to the user to inform them that the warm-up period has ended (i.e., the heater has reached temperature and puffing can begin). The alert may be a visual alert, a tactile feedback alert, or another suitable alert. In FIG. 3, the activation period of the heater element during the warm-up period is shown as period Awarmup. That is, the activation period of the heater element during warm-up is the period (i.e., the length of time) during which the heater element is activated to warm the heater element to an operating temperature.

[0120] As is known, the thermostatic heater control is configured to maintain the heater element temperature within the operating temperature band for the duration of a smoking session. As a result, when the heater is turned off (enters a deactivation period), the heater element cools down, as shown in Figure 3. When the temperature sensor senses that the heater element has cooled to a temperature below the lower limit (Tmin) of the operating temperature band, the thermostatic heater control activates (e.g., provides power to) the heater element. When power is provided to the heater element, the heater element warms up and the control process is repeated.

[0121] The time that the heater element is on is called an activation period, and the time that the heater is off is called a deactivation period. Successive activation and deactivation periods are called a thermostat cycle (Tcycle). A thermostat heater control typically completes multiple thermostat cycles during a smoking session. In FIG. 3, activation periods A1-An are shown after warm-up. When no puffs are occurring, the activation periods of successive thermostat cycles are relatively stable, as the heater element tends to cool down at a consistent rate from the upper limit during the deactivation periods. A typical activation period may be about 300 milliseconds.

[0122] In FIG. 3, a puff is shown to begin at Pstart. A puff consists of an inhalation by the user on the consumable to draw air from the consumable, where the aerosol is entrained in the airflow and inhaled by the user. The drawing of air from the consumable by the puffing action tends to act as a forced cooling of the heater element. As a result, it has been found that the activation period (Apuff) of the heater element after the start of a puff is detectably greater than the activation period of the preceding thermostat cycle. That is, by monitoring the activation period (i.e., heater on time), it is possible to detect a puff by determining that the activation period has exceeded a threshold value as described herein.

[0123] After the start of a puff, the heater element continues to thermostatically cycle to maintain the heater element between the lower and upper limits of the operating temperature band. With a constant puff (i.e., flow rate), the activation period can be below the threshold for determining a puff, and thus a puff can be determined whenever the activation period is longer than the threshold for determining a puff. Alternatively, or in addition, the control system can be configured to ignore activation periods within a period from a detected puff.

[0124] During a smoking session, the user is free to inhale with the device according to preference. As shown in FIG. 3, there is a discernible increase in activation period after the start of each puff (Pstart), as explained above. Thus, the number of puffs during a session can be counted by configuring the control system to count each time it is determined that the activation period exceeds a threshold. The control system can be configured to use puff detection or puff counting in operating the device's functions.

[0125] The control system is configured to stop a smoking session after a predetermined time has elapsed since its initiation. The end of the session can be alerted to the user, as can the initiation. After the session is over, the thermostatic heater control turns off power to the heater element, allowing the heater element to cool down in preparation for the initiation of the next session.

[0126] It is known to use puff counting to extend a smoking session if a minimum number of puffs has not been exceeded within a predetermined time period, and therefore it would be advantageous to have a repeatable and reliable determination of puffs.

[0127] The thermostatic cycle shown in FIG. 3 is representative and does not take into account hysteresis effects in temperature after on / off states of the heater element.

[0128] A threshold above which it is determined that an activation period represents the start of a puff can be preset in the control system. For example, in the absence of a puff, the heater element may be controlled to maintain temperature with an activation period of about 300 milliseconds, and the control system may be configured to recognize a heater activation period of more than 500 milliseconds as an indication that a puff has started, and thus determine a puff when the activation period exceeds a fixed threshold. In an alternative embodiment, the control system may determine that a puff has started based on an average activation period. For example, the activation periods A1-An may be averaged, and the control system monitors the activation period and determines a puff when the measured activation period becomes greater than the average. In some embodiments, it is envisioned that the control system may determine that a puff has occurred when the activation period becomes greater than the average by a predetermined offset. For example, if the average heater activation period is 310 milliseconds, the control system may be configured to calculate the threshold as the average plus a fixed offset. That is, if the fixed offset was 200 ms, the threshold for determining a puff would be an activation period greater than 510 ms, whereas in the same example, if the average was 290 ms, a puff would be determined when the activation period exceeded 490 ms. Alternatively, the control system may be configured to set the threshold as a percentage increase above the average. For example, if the percentage is set to be greater than 40%, then if the average was 300 ms, a puff would be determined when the heater activation period exceeded 420 ms, whereas if the average was 320 ms, a puff would be determined when the heater activation period exceeded 448 ms.

[0129] In an exemplary embodiment in which the threshold for determining a puff is based on the average activation period of previous thermostat cycles, the average may be a rolling average based on a fixed number of cycles preceding the activation period being determined.

[0130] While the present invention has been described in conjunction with the exemplary embodiments set forth above, many equivalent modifications and variations will be apparent to those skilled in the art given this disclosure. Accordingly, the exemplary embodiments of the invention set forth above are considered to be illustrative rather than limiting. Various changes may be made to the described embodiments without departing from the spirit and scope of the invention.

[0131] For the avoidance of any doubt, any theoretical explanations provided herein are provided for the purpose of improving the understanding of the reader, and the inventors do not wish to be bound by any of these theoretical explanations.

[0132] All headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described.

[0133] Throughout this specification, including the claims which follow, unless the context requires otherwise, the words "have," "comprise," and "include," as well as variations such as "having," "comprises," "comprising," and "including," will be understood to imply the inclusion of a stated integer or step or group of integers or steps, but not to exclude any other integers or steps or group of integers or steps.

[0134] It should be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. As used herein, ranges may be expressed as "about" one particular value and / or to "about" another particular value. When such a range is expressed, another embodiment includes from the one particular value and / or to the other particular value. Similarly, by use of the prefix "about," when values ​​are expressed as approximations, it will be understood that the particular value forms another embodiment. The term "about" in connection with numerical values ​​is optional and means, for example, ±10%.

[0135] The words "preferred" and "preferably" are used herein to refer to embodiments of the invention that may provide certain benefits, under some circumstances. It is to be understood, however, that other embodiments may also be preferred, under the same or different circumstances. Thus, reference to one or more preferred embodiments does not mean or imply that other embodiments are not useful, nor is it intended to exclude other embodiments from the scope of the disclosure or the claims.

Claims

1. An aerosol generating device (101, 201) comprising a heater element (223), a temperature sensor, and a control system (208) including a thermostatic heater control, the thermostatic heater control configured to activate and deactivate the heater element based on an output of the temperature sensor to maintain the temperature of the heater element within an operating temperature range, The control system is configured to determine that a puff has been initiated based on determining that the activation period exceeds a threshold. An aerosol generating device (101, 201).

2. The aerosol generating device (101, 201) according to claim 1, wherein the threshold value is a fixed threshold value.

3. The aerosol generating device (101, 201) according to claim 1, wherein the threshold value is based on an average of preceding activation periods.

4. 4. The aerosol generating device (101, 201) according to claim 3, wherein the average of preceding activation periods is an average of a fixed number of preceding activation periods.

5. 4. The aerosol generating device (101, 201) according to claim 3, wherein the threshold value is determined as a fixed offset from the average of preceding activation periods.

6. 4. The aerosol generating device (101, 201) according to claim 3, wherein the threshold value is determined as a percentage increase of the average of the preceding activation periods.

7. 2. The aerosol generating device (101, 201) of claim 1, wherein the control system uses the determination that a puff has been initiated to control further functions of the device.

8. 2. The aerosol generating device (101, 201) of claim 1, wherein the control system comprises a counting function for counting the number of determinations that a puff has been initiated.

9. 9. The aerosol generating device (101, 201) according to claim 8, wherein the counting function is reset at the end of a smoking session.

10. 10. The aerosol generating device (101, 201) of claim 9, wherein the control system is configured to extend the smoking session if a minimum count is not reached during the smoking session.

11. 2. The aerosol generating device (101, 201) of claim 1, wherein the device comprises an elongated body (209), an end of the elongated body configured to engage with an aerosol-forming article (102), and the heater element is configured to be inserted into the aerosol-forming article.

12. A system (100) comprising an aerosol generating device (101, 201) according to any one of claims 1 to 11 and an aerosol-forming article.

13. A method for controlling an aerosol generating device (101, 201), comprising: activating and deactivating a heater element (223) to maintain the temperature of said heater element within an operating temperature; determining that an activation period of the heater element exceeds a threshold; determining that a puff has begun based on the determination that the activation period of the heater element has exceeded the threshold.

14. 14. The method of claim 13, comprising calculating an average of preceding activation periods and determining the threshold value based on the calculated average.

15. 15. The method of claim 13 or 14, comprising counting the number of puff initiated determinations during a smoking session, and extending the smoking session if a minimum count is not reached during the smoking session.

Images