Detailed Description
Aspects and features of certain examples and embodiments are discussed or described herein. Some aspects and features of certain examples and embodiments may be conventionally implemented and are not discussed/described in detail for the sake of brevity. Thus, it should be understood that aspects and features of the apparatus and methods discussed herein that are not described in detail may be implemented in accordance with any conventional technique for implementing such aspects and features.
The present disclosure relates to vapor supply devices, such as electronic cigarettes, including mixing devices. Throughout the following description, the term "e-cigarette" or "e-cigarette" may be used at times, but it should be understood that the term may be used interchangeably with vapor supply system/device and electronic vapor supply system/device. Furthermore, and as is common in the art, the terms "vapor" and "aerosol" and related terms such as "evaporation," "aerosolization," and "aerosolization" are generally used interchangeably.
The aerosol provision device is for generating an aerosol from an aerosol generating material. An aerosol-generating material is a material that is capable of generating an aerosol, for example, when heated, irradiated or energized in any other way. The aerosol-generating material may for example be in solid, liquid or gel form, which may or may not contain an active substance and/or a fragrance. In some embodiments, the aerosol-generating material may comprise an "amorphous solid," which may alternatively be referred to as a "monolithic solid" (i.e., non-fibrous). In some embodiments, the amorphous solid may be a dried gel. Amorphous solids are solid materials that can retain some fluid (such as a liquid) within their interior. In some embodiments, the aerosol-generating material may comprise, for example, from about 50wt%, 60wt%, or 70wt% amorphous solids to about 90wt%, 95wt%, or 100wt% amorphous solids. The aerosol-generating material may comprise one or more active substances and/or flavours, one or more aerosol-former materials, and optionally one or more other functional materials. In some embodiments, the aerosol-generating material comprises a crystalline structure.
The configuration of the aerosol-supply device may vary depending on the form of the aerosol-generating material from which the aerosol-generating material is configured to generate an aerosol. However, although examples will be discussed below for various different forms of aerosol-generating material and correspondingly different aerosol-supply device configurations, the heating techniques discussed herein may be applied to all forms of aerosol-generating material.
Systems for generating aerosols typically, although not always, comprise a modular assembly comprising a reusable part (e.g. an aerosol supply device) and a replaceable (disposable) cartridge part, also referred to as a consumable. Typically, the replaceable cartridge portion will include vapor precursor material and a vaporizer, and the reusable portion will include a power source (e.g., a rechargeable battery), an activation mechanism (e.g., a button or suction sensor), and a control circuit. However, it should be understood that these different parts may also include additional elements according to functionality. For example, for a mixing device, the cartridge portion may also include additional flavoring elements provided as an insert ("pod"), such as a portion of tobacco. In this case, the flavor element insert itself may be removable from the disposable cartridge portion so that it may be replaced separately from the cartridge, for example, for flavor change or because the useful life of the flavor element insert is less than the useful life of the vapor-generating component of the cartridge. The reusable device portion typically also includes additional components, such as a user interface for receiving user input and displaying operational status characteristics.
For modular systems, the cartridge and reusable device components are electrically and mechanically coupled together for use, for example, using threads, latches, friction fits, or bayonet fixtures with properly engaged electrical contacts. When the vapor precursor material in the cartridge is exhausted, or when the user wishes to switch to a different cartridge having a different vapor precursor material, the cartridge may be removed from the device portion and a replacement cartridge attached in its place. Devices conforming to this type of two-piece modular configuration may generally be referred to as two-piece devices or multi-piece devices.
It is relatively common for an electronic cigarette to have a generally elongated shape, and to provide specific examples, certain embodiments of the present disclosure described herein will be considered to include a generally elongated, single-piece device employing a liquid reservoir containing a liquid vapor precursor material. However, it will be appreciated that the basic principles described herein may be equally applicable to different electronic cigarette configurations, for example, multi-piece devices employing disposable cartridges containing vapor precursor materials, or modular devices comprising more than two portions, refillable devices and single-use disposable devices, and hybrid devices having additional flavor elements, such as tobacco pod inserts located upstream of the airflow path and evaporator, as well as devices conforming to other overall shapes, for example, so-called box-mode high performance devices based on a generally box-like shape.
Various embodiments will now be described in more detail.
Fig. 1 is a cross-sectional view of a schematic drawing taken through an electronic vapor supply device 101 according to some embodiments.
The electronic vapor supply 101 includes an outer housing 160, a power source 140, a control circuit 130, one or more liquid sources 120, and a heating device 110. The outer housing 160 may be formed of any suitable material (e.g., plastic material). The outer housing 160 may also enclose other components, namely the power supply 140, the control circuit 130, the one or more liquid sources 120, and the heating device 110. The electronic vapour provision device 101 is a handheld electronic vapour device, which means that the outer housing 160 surrounding the other components is dimensioned and configured to be held in the hand of a user. In other words, the device is portable.
The electronic vapor supply 101 may also include a mouthpiece 150. The outer housing 160 and the mouthpiece 150 may be formed as a single component (i.e., the mouthpiece 160 forms a portion of the outer housing 160). The mouthpiece 150 may be defined as an area of the outer housing 160 that includes an air outlet and shaped so that a user may comfortably place their lips around the mouthpiece 150 to engage with the air outlet. In fig. 1, the thickness of the outer housing 160 decreases toward the air outlet to provide a relatively thin portion of the device 101 that may be more easily accommodated by the user's lips. However, in other implementations, the mouthpiece 150 may be a removable component separate from but coupleable to the outer housing 160, and may be removed for cleaning and/or replaced with another mouthpiece 150.
The power supply 140 is configured to provide operating power to the electronic vapor supply device 101. The power source 140 may be any suitable power source, such as a battery. For example, the power source 140 may include a rechargeable battery, such as a lithium ion battery. The power supply 140 may be removable or form an integral part of the electronic vapor supply 101. In some implementations, the power source 140 may be recharged by the device 101 by an associated connection port, such as a USB port (not shown), or by connecting to an external power source, such as mains, via a suitable wireless receiver (not shown).
The control circuit 130 is suitably configured or programmed to control the operation of the aerosol provision device to provide certain operational functions of the electronic vapor provision device 101. The control circuit may also be interchangeably referred to as a "controller". The control circuit 130 may be considered to logically include various sub-units/circuit elements associated with different aspects of the operation of the aerosol provision device. For example, the control circuit 130 may include a logic subunit for controlling recharging of the power supply 140. In addition, control circuitry 130 may include logic subunits for communication, for example, to facilitate transmission of data from or to device 101. However, the primary function of the control circuit 130 is to control the heating of the aerosol-generating material, as described in more detail below. It should be appreciated that the functionality of the control circuit 130 may be provided in a variety of different ways, for example using one or more appropriately programmed programmable computers and/or one or more appropriately configured application specific integrated circuits/chips/chipsets configured to provide the desired functionality. The control circuit 130 is connected to the power supply 140 and may receive power from the power supply 140 and may be configured to distribute or control the power supply to other components of the electronic vapor supply device 101. The control circuit 130 is discussed as being connected to the various components of the electronic vapor supply device 101, and it should be understood that this may be a direct or indirect connection in each case.
The electronic vapor supply 101 also includes one or more liquid sources 120, each of which includes a liquid reservoir containing a liquid vapor precursor material. The liquid vapor precursor material may be referred to as an electronic liquid. In embodiments, one or more liquid sources 120 are disposed within the outer housing 160, but as discussed above, in embodiments in which the electronic vapor supply 101 is a multi-component or modular system, the one or more liquid sources 120 may be disposed within a disposable cartridge configured to be releasably coupled to the remainder of the electronic vapor supply 101. That is, the cartridge can be received by or in the vapor supply 101.
Although specific embodiments will be discussed in more detail below, each liquid reservoir may be formed in any shape compatible with the heating techniques discussed herein. The one or more liquid reservoirs may also be formed according to conventional techniques, and for example, may comprise a plastic material and may be integrally formed with the outer housing 160.
An electronic vapor supply device according to various embodiments may include a heating assembly 10, as schematically illustrated in fig. 2. The heating assembly 10 may be connected to a control circuit 30. According to various embodiments, the heating assembly 10 uses Radio Frequency (RF) electromagnetic radiation, such as microwave radiation, although other wavelengths may be used to heat the liquid vapor precursor material. RF electromagnetic radiation refers to electromagnetic radiation having a frequency in the range of 30Hz to 300 GHz. The RF electromagnetic radiation may have a frequency of 3kHz to 300GHz (alternatively 3MHz to 100GHz, alternatively 30MHz to 30 GHz). The heating assembly 10 may include a signal generator 170, such as a voltage controlled oscillator ("VCO"), to generate a signal that is provided to a connected amplifier 180. The amplifier 180 may be connected to one or more antennas 115 disposed within the heating chamber 120. In some embodiments, the one or more antennas 115 include one or more patch antennas. In another embodiment, the one or more antennas 115 include one or more directional antennas. The control circuitry 30 may control the RF electromagnetic radiation generated by the one or more antennas 115 and, in an embodiment, the frequency spectrum generated by the one or more antennas 115. One or more antennas 115 may also be referred to as an antenna arrangement 115.
The heating cavity 120 is defined by an RF shield 111 that substantially prevents RF electromagnetic radiation generated by the one or more antennas 115 from escaping from the heating cavity 120. The RF shield 311 defines a heating cavity 320 by defining a volume that substantially prevents RF electromagnetic radiation from escaping, as will be discussed below. One or more antennas 115 are disposed within the heating chamber 120. The escape of RF electromagnetic radiation from the heating cavity 120 may be prevented by a combination of reflection and absorption of RF electromagnetic radiation, and optionally, the RF shield 111 may be configured to reflect more RF electromagnetic radiation back into the heating cavity 120 than is absorbed by the RF shield 111.
For example, RF shield 111 may be configured to have a directional reflectivity of 0.5 to 1.0, alternatively 0.7 to 1.0, for RF electromagnetic radiation generated by antenna 115, the directional reflectivity being the radiant flux reflected by a surface divided by the radiant flux received by the surface. The RF shield 111 may be configured to have a directional absorption of 0.0 to 0.7, optionally 0.1 to 0.5, for RF electromagnetic radiation generated by the antenna, the directional absorption being the radiant flux absorbed by the surface divided by the radiant flux received by the surface. Further, the RF shield 111 may be configured to have a directional transmissivity of 0.0 to 0.3, alternatively 0.1 to 0.2, to RF electromagnetic radiation generated by the antenna 115, the directional transmissivity being the radiant flux transmitted by the surface divided by the radiant flux received by the surface. In addition, the RF shield may be configured to have an effective attenuation coefficient for RF electromagnetic radiation generated by the antenna of at least 0.05mm-1, optionally at least 0.1mm-1, optionally at least 0.2mm-1, optionally at least 0.5mm-1, wherein the effective attenuation coefficient is the radiation flux absorbed and scattered by a volume per unit length divided by the radiation flux received by the volume.
In some embodiments, RF shield 111 comprises a conductive material, a magnetic material, advantageously a conductive magnetic material, and may comprise a metal, such as aluminum, copper, brass, nickel, or other metals. Aluminum, copper, brass, and nickel are particularly useful because they have desirable high reflectivity and gloss in addition to conductivity. The RF shield 111 may include a substrate (e.g., an electrically insulating substrate) with a metallic coating (such as metallic ink). In an embodiment, the RF shield 111 may include an alloy having aluminum or copper. In some implementations, the RF shield 111 includes a reflective foil. The RF shield 111 may comprise a sheet metal material. In other embodiments, the RF shield 111 may comprise a metal gauze or mesh. For example, the RF shield 111 may include an opening having a width of 5mm or less, alternatively 2.5mm or less, alternatively 1.5mm or less, alternatively 1.0mm or less, alternatively 0.5mm or less, alternatively 0.2mm or less, alternatively 0.1mm or less. Although any of these sized openings may be applied to the liquid delivery region or the vapor permeable region, as discussed below, an opening having a width of 2.5mm or less may be well suited to allow passage of air and liquid and mixtures of air, liquid and/or vapor, while an opening having a width of 0.5mm or less may be suited to allow passage of liquid. These narrow openings are sufficient to substantially prevent RF electromagnetic radiation from escaping the heating chamber 120 while still allowing fluid to pass through. In an embodiment, the opening may have a width that is less than a minimum wavelength of RF electromagnetic radiation generated by the antenna 115. Furthermore, in areas of the RF shield 111 that include openings (e.g., liquid delivery areas or breathable areas, as discussed below), the openings may cover 20% to 80%, alternatively 40% to 60%, of the surface area of these areas. This ratio of openings may enable a desired volume of fluid to pass through the RF shield 111 while maintaining structural stability.
Thus, when one or more antennas 115 are used to generate RF electromagnetic radiation, the material within the cavity may be heated by exposure to the radiation through a dielectric heating mechanism in which polar molecules of the material within the cavity are driven in rotation by the RF electromagnetic radiation, thereby causing the material within the cavity to evaporate. However, the RF shield 111 may be arranged to substantially prevent RF electromagnetic radiation from escaping the cavity 120. This is important, particularly for handheld electronic vapor supplies, because any RF electromagnetic radiation escaping from the heating chamber 120 escapes near the user. In one aspect, providing an RF shield may help prevent RF radiation from escaping out of the RF shield, and thus provide a relatively safe heating mechanism (in terms of preventing user exposure to RF radiation). In addition, where the RF shield is at least partially reflective of RF radiation, the intensity of the generated RF electromagnetic radiation may increase within the range of the RF shield.
As will be discussed in more detail below with respect to exemplary embodiments, liquid vapor precursor material may be provided to the heating chamber 120 through the liquid delivery region 121 of the RF shield 111. To enable the liquid vapor precursor material to enter the heating chamber 120 while still containing RF electromagnetic radiation, the liquid delivery region 121 corresponds to a portion of the RF shield 111 that is configured to allow fluid to pass therethrough but that is still configured such that RF electromagnetic radiation is substantially prevented from passing therethrough, i.e., RF electromagnetic radiation is substantially prevented from escaping the heating chamber 120. Thus, the liquid delivery region 121 allows liquid to enter the heating assembly without requiring a gap in the RF shield that would substantially allow RF electromagnetic radiation to escape.
To achieve this, the liquid delivery region 121 of the RF shield 111 includes an opening sized to allow liquid to flow therethrough, but sized to substantially prevent RF electromagnetic radiation from passing therethrough, which may be of the above-described dimensions. As will be discussed in more detail below, the liquid delivery region 121 may be defined by one or more wicking members configured to transport liquid from a liquid source across the RF shield 111 by capillary action. It will be appreciated that the degree or size of capillary action may be affected by the nature (e.g., viscosity) of the liquid being wicked and the size of the openings (or more generally capillary channels) of the liquid delivery region 121. However, while many of the examples below will be discussed in the context of liquid delivery regions provided by one or more wicking members, these examples may each be more generally applied to arrangements in which one or more liquid delivery regions are provided and may or may not have wicking properties. In other words, one or more wicking members may be generalized to one or more liquid delivery zones that allow fluid to be transmitted therein, but prevent RF electromagnetic radiation from being transmitted therein.
As shown in detail in the various embodiments discussed below, the liquid delivery region 121 of the RF shield 111 is in fluid communication with one or more liquid sources 20. The liquid vapor precursor material is capable of flowing from one or more liquid reservoirs and through the liquid delivery region 121 into the heating chamber 120. The liquid delivery region 121 may include one or more liquid delivery regions 121 disposed in different regions relative to the heating chamber 120, each liquid delivery region in fluid communication with a corresponding liquid source of the one or more liquid sources. In an embodiment, the liquid vapor precursor material may be drawn through the liquid delivery region 121 by capillary action. Each liquid source 20 may include a flow control element configured to control the flow of liquid from the liquid reservoirs of the liquid source, and one or more liquid sources 20 may be connected to the control circuit 30 such that the flow from each liquid reservoir into the heating chamber 120 may be controlled by the control circuit 30. Alternatively, the liquid delivery region 121 may be arranged to provide a specific liquid supply rate (e.g., by an appropriate number of openings/size of openings relative to the characteristics of the respective liquid source) to control the relative amount of liquid within the RF shield 111.
After entering the cavity, the liquid vapor precursor material may be held by a support structure (not shown) configured to hold the liquid vapor precursor material within the cavity. Where there are multiple liquid delivery zones, each zone may be configured to deliver liquid vapor precursor material to a respective support structure. The support structure may be (an area of) an inner wall of the RF shield 111 (e.g. at the liquid delivery area), and/or may be a separate support structure arranged within the heating chamber 120, i.e. an inner support structure. In addition to substantially preventing RF electromagnetic radiation from escaping the heating chamber 120, the RF shield 111 may also be configured to optimally direct radiation toward the support structure and the liquid vapor precursor material held thereby. When one or more antennas 115 are used to generate RF electromagnetic radiation within the heating chamber 120, it is this liquid vapor precursor material located within the chamber and held by the support structure that is heated and at least partially vaporized to generate vapor in the heating chamber 120. This may be a relatively small amount of liquid vapor precursor material, so that it can advantageously be heated and evaporated very quickly. It is therefore also important to ensure that the control circuit 30 is configured to control the heating assembly 10 in a manner that ensures that such evaporation occurs under optimal conditions, as will be discussed in more detail. To this end, the heating assembly 10 may include one or more sensors, including a temperature sensor, a chemical sensor, and/or a humidity sensor for detecting conditions in the cavity, which are connected to the control circuit 30. Alternatively, algorithms (such as algorithms that apply observer control theory, or artificial intelligence and/or machine learning) may be used to estimate temperature.
The electronic vapor supply 101 may include an air flow path extending between the heating cavity 120 that serves as a vapor generation chamber and an air outlet (such as an opening in a mouthpiece) such that a user may draw air from the heating cavity 120 via the mouthpiece over the outlet, the drawn air including any vapor generated by the liquid vapor precursor material in the heating cavity 120 for inhalation by the user. The flow path may start from an air inlet, such as an inlet in an outer housing (not shown), for directing air toward the heating chamber 120, and is defined by one or more air channels (not shown). To facilitate such airflow through heating chamber 120, RF shield 111 may also include a gas permeable region that may include an opening in RF shield 111, yet still substantially prevent RF electromagnetic radiation from escaping from the chamber. These venting areas of RF shield 111 may include openings having a width of 2.5mm or less and may be metallic as discussed above. This allows air flow 131 into heating chamber 120, which may collect vapor generated by dielectric heating within the chamber and exit the heating chamber as air flow 132 for inhalation by a user. As shown in fig. 2 and subsequent figures, the airflow into and/or out of the heating chamber is indicated by one or more arrows through the RF shield indicating the airflow (optionally including vapors generated in the chamber during use) through the RF shield. To facilitate this, a first venting area may be arranged at one side of the heating chamber 120, while a second venting area is arranged at the other (opposite) side of the heating chamber 120, such that air is drawn into the heating chamber (e.g., from an air inlet), passes through the first venting area, passes through the heating chamber, and exits the second venting area.
In other embodiments, as schematically illustrated in fig. 3, a vapor supply 301 may be used to generate an aerosol from a solid or gel aerosol-generating material. Similar to the liquid aerosol-generating material system shown in fig. 1, the electronic vapour provision device 301 comprises an outer housing 360, a power source 340, a control circuit 330 and a heating apparatus 310. However, the electron vapor supply device 301 does not include a liquid source. The vapor supply 301 may have any of the features discussed above with respect to the aerosol supply 101, where applicable.
As with the arrangement shown in fig. 1, the outer housing 360 may be formed of any suitable material (e.g., a plastic material). The outer housing 360 may also enclose other components, namely the power supply 340, the control circuit 330, and the heating device 310. The electronic vapour provision device 301 is a handheld electronic vapour device, which means that the outer housing 360 surrounding the other components is dimensioned and configured to be held in the hand of a user. In other words, the device is portable. Similar to the arrangement shown in fig. 1, the electronic vapor supply 301 may also include a mouthpiece 350 having similar features to the arrangement of fig. 1.
The power supply 340 may also be configured in the same manner as fig. 1 to provide operating power to the electronic vapor supply device 301 and may have the same features. Likewise, the control circuit 330 is suitably configured or programmed to control operation of the aerosol provision device to provide certain operational functions of the electronic vapor provision device 301. The control circuit may also be interchangeably referred to as a "controller". The control circuit 330 may be considered to logically include various sub-units/circuit elements associated with different aspects of the operation of the aerosol provision device. For example, the control circuit 330 may include logic subunits for controlling recharging of the power supply 340. In addition, control circuitry 330 may include logic subunits for communication, for example, to facilitate transmission of data from or to device 301. However, the primary function of the control circuit 330 is to control the heating of the aerosol-generating material, as described in more detail below. It should be appreciated that the functionality of the control circuit 330 may be provided in a variety of different ways, for example using one or more appropriately programmed programmable computers and/or one or more appropriately configured application specific integrated circuits/chips/chipsets configured to provide the desired functionality. The control circuit 330 is connected to the power source 340 and may receive power from the power source 340 and may be configured to distribute or control the power source to other components of the electronic vapor supply device 101. The control circuit 130 is discussed as being connected to the various components of the electronic vapor supply device 101, and it should be understood that this may be a direct or indirect connection in each case.
However, the heating assembly 310 is different from that shown in fig. 1. In a vapor supply for heating aerosol-generating material in solid or gel form, the heating assembly 310 includes a heating chamber 380 into which the aerosol-generating material may be inserted (e.g., within a consumable). Although not shown in fig. 3, the mouthpiece 350 of this example is releasably attached to the outer housing 360 and removed to allow access to the heating chamber 360. When reattached to the outer housing 360, the mouthpiece closes the opening to the chamber 380. Also, although not shown, a portion of the RF shield 311 (defined below) may be disposed on/in the mouthpiece 350 (and possibly extend across an opening in the mouthpiece 350) to complete the RF shield 311 extending around and surrounding the heating chamber 380. The heating assembly 310 may be connected to the control circuit 130 and use Radio Frequency (RF) electromagnetic radiation, such as microwave radiation, although other wavelengths may be used to heat aerosol-generating material received within the heating chamber 380. RF electromagnetic radiation refers to electromagnetic radiation having a frequency in the range of 30Hz to 300 GHz. The RF electromagnetic radiation may have a frequency of 3kHz to 300GHz (alternatively 3MHz to 100GHz, alternatively 30MHz to 30 GHz). The heating component 310 may include a signal generator 370, such as a voltage controlled oscillator ("VCO"), to generate a signal that is provided to a connected amplifier 380. The amplifier 380 may be connected to one or more antennas 315 disposed within the heating chamber 320. In some implementations, the one or more antennas 315 include one or more patch antennas. In another embodiment, the one or more antennas 315 include one or more directional antennas. Control circuitry 330 may control the RF electromagnetic radiation generated by one or more antennas 315 and, in an embodiment, the frequency spectrum generated by one or more antennas 315. One or more antennas 315 may also be referred to as an antenna arrangement 315.
The heating cavity 320 is defined by an RF shield 311 that substantially prevents RF electromagnetic radiation generated by the one or more antennas 315 from escaping from the heating cavity 320. The RF shield 311 defines a heating cavity 320 by defining a volume that substantially prevents RF electromagnetic radiation from escaping, as will be discussed below. One or more antennas 115 are disposed within the heating chamber 320. The escape of RF electromagnetic radiation from heating cavity 320 may be prevented by a combination of reflection and absorption of RF electromagnetic radiation, and optionally RF shield 311 may be configured to reflect more RF electromagnetic radiation back into heating cavity 320 than is absorbed by RF shield 311.
For example, in the same manner as RF shield 111 discussed above, RF shield 311 may be configured to have a directional reflectivity of 0.5 to 1.0, alternatively 0.7 to 1.0, for RF electromagnetic radiation generated by the antenna, the directional reflectivity being the radiant flux reflected by the surface divided by the radiant flux received by the surface. The RF shield 311 may be configured to have a directional absorption of 0.0 to 0.7, alternatively 0.1 to 0.5, for RF electromagnetic radiation generated by the antenna, the directional absorption being the radiant flux absorbed by the surface divided by the radiant flux received by the surface. Further, the RF shield 311 may be configured to have a directional transmissivity of 0.0 to 0.3, alternatively 0.1 to 0.2, to RF electromagnetic radiation generated by the antenna, the directional transmissivity being the radiant flux transmitted by the surface divided by the radiant flux received by the surface. In addition, the RF shield may be configured to have an effective attenuation coefficient for RF electromagnetic radiation generated by the antenna of at least 0.05mm-1, optionally at least 0.1mm-1, optionally at least 0.2mm-1, optionally at least 0.5mm-1, wherein the effective attenuation coefficient is the radiation flux absorbed and scattered by a volume per unit length divided by the radiation flux received by the volume.
In some embodiments, RF shield 311 comprises a conductive material, a magnetic material, advantageously a conductive magnetic material, and may comprise a metal, such as aluminum, copper, brass, nickel, or other metals. Aluminum, copper, brass, and nickel are particularly useful because they have desirable high reflectivity and gloss in addition to conductivity. The RF shield 311 may include a substrate (e.g., an electrically insulating substrate) with a metallic coating (such as metallic ink). In an embodiment, the RF shield 311 may include an alloy having aluminum or copper. In some implementations, the RF shield 311 includes a reflective foil. The RF shield 311 may comprise a sheet metal material. In other embodiments, the RF shield 311 may comprise a metal gauze or mesh. For example, the RF shield 311 may include an opening having a width of 5mm or less, alternatively 2.5mm or less, alternatively 1.5mm or less, alternatively 1.0mm or less, alternatively 0.5mm or less, alternatively 0.2mm or less, alternatively 0.1mm or less. Although any of these sized openings may be applied to the liquid delivery region or the vapor permeable region, as discussed below, an opening having a width of 2.5mm or less may be well suited to allow passage of air and liquid and mixtures of air, liquid and/or vapor, while an opening having a width of 0.5mm or less may be suited to allow passage of liquid. These narrow openings are sufficient to substantially prevent RF electromagnetic radiation from escaping heating chamber 320 while still allowing fluid to pass through. In an embodiment, the opening may have a width that is less than a minimum wavelength of RF electromagnetic radiation generated by the antenna 115. Further, in areas of the RF shield 311 that include openings (e.g., liquid delivery areas or gas permeable areas, as discussed below), the openings may cover 20% to 80%, alternatively 40% to 60%, of the surface area of these areas. This ratio of openings may enable a desired volume of fluid to pass through the RF shield 111 while maintaining structural stability.
Thus, when one or more antennas 315 are used to generate RF electromagnetic radiation, the material within the cavity may be heated by exposure to the radiation by a dielectric heating mechanism in which polar molecules of the material within the cavity are driven in rotation by the RF electromagnetic radiation, thereby causing the material within the cavity to evaporate. However, the RF shield 311 may be arranged to substantially prevent RF electromagnetic radiation from escaping the cavity 320. This is important, particularly for handheld electronic vapor supplies, because any RF electromagnetic radiation escaping from heating chamber 320 will escape in the vicinity of the user. In one aspect, providing an RF shield may help prevent RF radiation from escaping out of the RF shield, and thus provide a relatively safe heating mechanism (in terms of preventing user exposure to RF radiation). In addition, where the RF shield is at least partially reflective of RF radiation, the intensity of the generated RF electromagnetic radiation may increase within the range of the RF shield.
The aerosol-generating material within the consumable inserted into heating chamber 380 may be sufficient to generate aerosol for inhalation by the user multiple times in a given session. However, the consumable may be designed to be replaced in each session, and thus the amount of aerosol-generating material within the consumable (and in particular within the heating chamber) may not be significant. As discussed above, this is also true for aerosol provision devices for heating liquid aerosol-generating materials. Thus, in aerosol provision devices for liquid aerosol-generating materials and aerosol provision devices for aerosol-generating materials in solid or gel form, the volumetric characteristics of the material within the heating chamber may vary significantly during inhalation.
Regardless of the form of the aerosol-generating material (liquid, solid or gel), the aerosol-supplying device may be configured to apply heat to the aerosol-generating material during one or more heating cycles. In particular, the control circuit is configured to control the heating assembly (in particular the at least one antenna) such that RF electromagnetic radiation is applied during one or more heating cycles, a set of one or more heating cycles corresponding to generating an aerosol from the aerosol-generating material for inhalation.
The heating efficiency (in a liquid arrangement or a solid or gel arrangement) of the aerosol-generating material generated by exposure to RF electromagnetic radiation within the heating chamber depends on the dielectric loss of the aerosol-generating material. Dielectric loss is defined as the inherent electromagnetic energy dissipation of a material, which may depend on the material composition and material temperature, and also on the characteristics of the electromagnetic energy received. Thus, by varying the generation of RF electromagnetic radiation during the inhalation process, or varying the heating cycle configured to generate an aerosol for a given inhalation, the aerosol-supply device may adapt the heating to variations in the characteristics of the aerosol-generating material.
The controller may be configured to alter one or several of several different characteristics of the RF electromagnetic radiation generated by the one or more antennas during one or more heating cycles or inhalation processes. As the temperature of the aerosol-generating material within the heating chamber changes, the relationship between dielectric loss and radiation frequency also changes; the frequency at which efficient heating occurs may be different. Thus, one parameter that may be changed by the controller is the frequency of the RF electromagnetic radiation. The frequency of most efficient heating tends to increase with temperature over the range of temperatures in which the aerosol provision device may operate, and thus the controller may be configured to increase the frequency of RF electromagnetic radiation during one or more heating cycles or inhalations.
Another parameter that may be varied during one or more heating cycles or inhalations is the power of the RF electromagnetic radiation, as high power RF electromagnetic radiation may be applied for an initial period of time to bring the aerosol-generating material to a temperature at which an aerosol is generated, followed by a period of time to apply low power RF electromagnetic radiation in order to maintain the aerosol-generating material at a desired temperature. Here, the power of the RF electromagnetic radiation may be increased by increasing the amplitude of the RF electromagnetic radiation.
The arrangement of aerosol-generating material within the heating chamber may also be changed during one or more heating cycles or inhalation procedures. For example, in consumables containing aerosol-generating material in solid or gel form, the region of aerosol-generating material may be heated at different rates and depleted for different periods of time during one heating cycle or inhalation, or during many heating cycles or inhalations. In case the liquid aerosol-generating material reaches the heating chamber via the liquid delivery region, the liquid aerosol-generating material may be depleted first in the given region. Thus, the controller may alter the spatial distribution of RF electromagnetic radiation generated by the one or more antennas in response to such alteration of the arrangement of aerosol-generating material.
In an embodiment, the controller is configured to change the characteristic of the RF electromagnetic radiation generated by the at least one antenna in accordance with a predicted change in the characteristic of the aerosol-generating material during one or more heating cycles or inhalations. For example, the predicted change in the characteristic of the aerosol-generating material may depend on the composition of the aerosol-generating material during one or more heating cycles or inhalations, and using this or other information, the control circuit may be configured to select the predetermined change in the characteristic of the RF electromagnetic radiation accordingly. The aerosol provision device may comprise a consumable recognition sensor connected to the control circuit, the consumable recognition sensor being configured to recognize the type of consumable received by the aerosol provision device and may accordingly recognize the material composition of the aerosol provision material received in the heating chamber and may recognize the arrangement of one or more aerosol provision materials in the heating chamber. The consumable recognition sensor may be configured to recognize a consumable recognition component of the consumable. The consumable recognition component may be configured to be optically recognized by a consumable recognition sensor comprising a camera. The consumable identification component may be configured to be identified by a wireless electromagnetic interrogation, in which case the consumable identification sensor may be an electromagnetic transceiver.
In embodiments in which the aerosol-generating material is in solid or gel form, the consumable may be provided in the form of a rod or other substantially rigid shape inserted into the heating chamber; and thus the consumable recognition sensor may be configured to recognize the consumable in the cavity. In embodiments in which the aerosol-generating material is in liquid form, the consumable may be a cartridge that retains liquid in the reservoir as discussed above, and the cartridge may not enter the heating chamber. Thus, in such an arrangement, the consumable recognition sensor may be configured to recognize the consumable when the consumable is received by and coupled to the electronic vapor supply, but not necessarily within the cavity.
User usage behavior may also affect the predicted characteristics of the aerosol-generating material within a given cycle. Consumables that have been used in multiple sessions or heating cycles may behave differently and consume more in a given area, and consumables that have recently been heated may still have some waste heat stored therein. Thus, the control circuit may change the characteristics of the RF electromagnetic radiation according to the user's history of use. The control circuit may be further configured to vary the characteristics of the RF electromagnetic radiation in accordance with the characteristics of the applied heating cycle. For example, longer heating cycles may have more significant temperature changes and specific area losses of the aerosol-generating material.
In other embodiments, the vapor supply device further comprises one or more sensors for sensing a measured characteristic related to the aerosol-generating material in the heating chamber. The sensors are connected to the controller and the controller is configured to change a characteristic of the RF electromagnetic radiation based on the measured characteristic. In one example, the characteristics of the RF electromagnetic radiation may vary during one or more heating cycles or inhalations in accordance with feedback from a puff sensor configured to detect the intensity or intensity of a user inhalation.
If the user inhales very strongly, this may cause a rapid change in the characteristics of the aerosol-generating material in the heating chamber, as the aerosol generated in the chamber may be depleted more rapidly; and this is satisfied by the control circuit changing the characteristics of the RF electromagnetic radiation at a high rate. For example, the controller may be configured to change the frequency (or another characteristic) of the RF electromagnetic radiation at a rate of change that is a first rate set according to the intensity or intensity of user inhalation and that increases as the intensity or intensity of user inhalation increases or decreases as the intensity or intensity of user inhalation decreases. For example, if the measured characteristic is within a first range (e.g., above a predetermined level), the rate may be increased, and if the measured characteristic is within a second range (e.g., below a predetermined level), the rate may be decreased. For example, considering that the measurement characteristics are related to the inhalation of the user, a strong inhalation may be related to a more rapid change in the temperature or volume of the liquid in the heating chamber, which means that it may be necessary to change the frequency of the RF electromagnetic radiation more rapidly in order to provide efficient heating.
In an embodiment, the aerosol provision device is configured to alter the RF electromagnetic radiation during one or more inhalations. The onset and duration of these inhalations may be predicted, for example, the controller may predict that onset of inhalation occurs a predetermined time after the user activates the device and for a predetermined duration. Alternatively, the onset and duration of inhalation may be detected by one or more sensors (such as using a suction sensor) by using measured characteristics; however other sensors, such as temperature sensors, may also be used to detect when inhalation starts and ends.
The variation of the characteristic of the RF electromagnetic radiation may be provided by continuously varying, for example, the frequency or power of the RF electromagnetic radiation in a continuous manner, which may enable fine control of the characteristic variation. Alternatively, the characteristics of the RF electromagnetic radiation may be varied in a stepwise manner, which may have lower requirements on the control circuitry. In case the aerosol provision device comprises a plurality of antennas, the characteristics of the RF electromagnetic radiation may be changed by the controller controlling the first antenna to generate RF electromagnetic radiation and subsequently controlling the second antenna to generate RF electromagnetic radiation. The first antenna may be arranged at a different location than the second antenna to generate RF electromagnetic radiation directed to a different region of the heating cavity, or may be configured to emit RF electromagnetic radiation of a different frequency or range of frequencies.
When the control circuit controls one or more antennas in the heating assembly to generate RF electromagnetic radiation, in an embodiment, the electromagnetic radiation is generated according to a particular scheme. In particular, this means that the characteristics of the RF electromagnetic radiation are set according to the scheme of the control circuit that sets the characteristics of the RF electromagnetic radiation; such as the frequency, amplitude and distribution of RF electromagnetic radiation, which antenna is used to generate the RF electromagnetic radiation and when, and the temporal variations of these characteristics.
The protocol is a predetermined protocol that is defined prior to a user activating the aerosol provision device to cause the heating assembly to initiate a heating cycle, for example by drawing on the device to trigger activation via a draw sensor, or by pressing a button on the device. For example, the predetermined scheme may be stored in the memory of the control circuit before the user begins the heating cycle.
In some cases, the predetermined scheme is defined as being set by a user operating the aerosol provision device or by an auxiliary device (such as a computer, phone or tablet computer) connected to the aerosol provision device, the auxiliary device being specifically connected to a signal receiver in the aerosol provision device connected to the control circuit. The user may use the user interface of the aerosol provision device or auxiliary device to, for example, select the characteristics of the RF electromagnetic radiation they want to use for aerosol generation. The user interface may then send instructions to the control circuit related to the input received from the user, and the signal receiver may receive a signal from the auxiliary device related to the user input on the auxiliary device and send instructions to the control circuit. The signal receiver may facilitate connection to the auxiliary device via a wired or wireless connection.
This may be accomplished by selecting a desired predetermined protocol from a library of different predetermined protocols, or alternatively, the user may define the characteristics of the predetermined protocol itself prior to activation of the heating assembly. For example, a user may prefer to inhale an aerosol that provides a more intense taste in some aspects than in other aspects, and thus the user may select or define a predetermined scheme to ensure that the frequency distribution of RF electromagnetic radiation applied to the aerosol-generating material is conducive to more efficient heating of the material within the composition, thereby generating a desired taste. In other aspects, the user may desire a stronger, more intense aerosol inhalation experience, in which case they may choose to decide or define a predetermined scheme that requires more power to be applied to the consumable. In addition, the user may also want to heat a specific area of the consumable, which will cause a given aerosol to be generated from the aerosol-generating material arranged within that area; the predetermined scheme may thus be selected or defined accordingly, which causes the generation of RF electromagnetic radiation that is more strongly directed towards the region.
In other arrangements, the predetermined scheme may be defined or selected by the control circuit in response to receiving information relating to the composition of the aerosol-generating material. For example, the aerosol provision device may comprise a consumable recognition sensor configured to determine a characteristic of the consumable it receives and to communicate that information to the control circuit. The control circuit may then select or define a predetermined scheme based on this information. For example, different aerosol-generating compositions may be effectively heated by RF electromagnetic when exposed to different frequencies. Furthermore, some aerosol-generating compositions may require the application of higher power RF electromagnetic radiation to generate a satisfactory amount of aerosol, while the power used to heat other materials may be advantageously reduced, where possible, to conserve battery usage. Different consumables may also include different spatial arrangements in which the aerosol-generating composition is disposed or may be heated more efficiently when RF electromagnetic radiation is applied to different regions.
The various embodiments described herein are presented solely to aid in the understanding and teaching of the claimed features. These embodiments are provided as representative examples of embodiments only, and are not exhaustive and/or exclusive. It is to be understood that the advantages, embodiments, examples, functions, features, structures and/or other aspects described herein are not to be considered limitations on the scope of the invention as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilized and modifications may be made without departing from the scope of the claimed invention. Various embodiments of the invention may suitably comprise, consist essentially of, or consist of, suitable combinations of the disclosed elements, components, features, parts, steps, means, etc. in addition to those specifically described herein. In addition, the present disclosure may include other inventions not presently claimed but which may be claimed in the future.