Power system for aerosol generating devices

Abstract

An aerosol generating device power system (300) is provided. The power system includes a first power module (104) and a second power module (106). A first voltage converter (310) is connected between the first power module and a heater component (108) of the aerosol generating device and configured to boost the voltage of the power flow from the first power module to the heater component. A second voltage converter (312) is connected between the second power module and the first power module.

Description

[Technical Field]

[0001] The present invention relates to aerosol generating devices, and more particularly to power systems for aerosol generating devices. [Background technology]

[0002] Aerosol generating devices, such as e-cigarettes and other aerosol inhalers or vaporization devices, have become increasingly popular consumer products.

[0003] Heating devices for vaporization or aerosolization are known in the art. Such devices typically include a heating chamber and a heater. In operation, an operator inserts the product to be aerosolized or vaporized into the heating chamber. The product is then heated by an electronic heater to vaporize the product's ingredients for inhalation by the operator. In some examples, the product is a tobacco product similar to a traditional cigarette. Such devices are sometimes referred to as "heat-not-burn" devices, in that the product is heated to the point of aerosolization without being burned. Summary of the Invention [Problem to be solved by the invention]

[0004] Challenges faced by known aerosol generating devices include providing effective power management and heating. [Means for solving the problem]

[0005] In a first aspect, there is provided a power system for an aerosol generating device, the power system comprising: a first power module; a second power module; a first voltage converter connected between the first power module and a heater component of the aerosol generating device and configured to boost the voltage of the power flow from the first power module to the heater component; and a second voltage converter connected between the second power module and the first power module.

[0006] In this manner, by boosting the voltage from the first power module, a smaller first power module can be utilized in the power system while still achieving continuous power delivery to the heater component. This, in turn, can reduce the overall size of the aerosol generating device that includes the power system. The first voltage converter allows for the use of a lower voltage, which helps stabilize power delivery and improve the quality of the aerosolization session.

[0007] Preferably, the second voltage converter is controlled using input current control.

[0008] Preferably, the second voltage converter uses input current control to supply substantially constant power to the heater from each of the second power module and the first power module depending on the voltage of the first power module.

[0009] In this way, the second power module provides a continuous power flow independent of the voltage of the first power module, which stabilizes the power system and reduces losses in the first power module when its voltage drops. As a result, higher energy efficiency is achieved, especially at low voltages, which helps utilize more of the energy stored in the first power module and allows for smaller component sizes.

[0010] Preferably, the power system of the aerosol generating device is connectable to an auxiliary power source, and input current control in the second voltage converter controls the power flow from the auxiliary power source to the heater for an aerosolization session.

[0011] In this way, by using input current control in the second voltage converter, other power sources (including external power supplies) can be used in place of the second power module, thereby increasing the flexibility of the power system.

[0012] Preferably, the second power module is configured to recharge the first power module.

[0013] In this way, the first power module can power an aerosolization session for a longer period of time and / or can be adequately charged for a subsequent aerosolization session, thereby improving power usage in the power system.

[0014] Preferably, the second voltage converter is configured to boost the voltage of the power flow from the second power module to the first power module when recharging the first power module from the second power module.

[0015] In this way, a second power module with a lower voltage can be used.

[0016] Preferably, the first power module is a supercapacitor module including one or more supercapacitors, or the first power module is a battery module including one or more high-power batteries.

[0017] A high power battery is a battery that has a high discharge rate and is capable of providing high power output.

[0018] Preferably, the first power module may include one or more electrochemical double layer capacitors.

[0019] Preferably, the first power module is capable of providing a high power / discharge rate, for example 10 W / Wh or more, or more preferably 40 W / Wh or more. It is particularly preferred to have a discharge rate of 40 W / Wh or more for the duration of preheating.

[0020] In this way, a supercapacitor or high power battery can be used to quickly transfer energy from the first power module to the heater component.

[0021] Preferably, the second power module is a battery module including at least one battery, or the second power module is a supercapacitor module including one or more supercapacitors, or the second power module is a supercapacitor module including one or more hybrid supercapacitors.

[0022] In this way, a high amount of energy can be stored in the second power module for recharging the first power module and / or for powering the heater components.

[0023] In a second aspect, there is provided an aerosol generating device comprising the aerosol generating device power system of the first aspect.

[0024] Preferably, the aerosol-generating device comprises a heating chamber configured to receive an aerosol-generating consumable and to heat the aerosol-generating consumable, without combustion, to generate an aerosol during an aerosolization session.

[0025] In this way, consumers can engage in an aerosolization session that provides an experience similar to traditional smoking.

[0026] Preferably, the heating chamber has a generally circular cross-section and defines a generally cylindrical cavity for receiving the aerosol-generating consumable.

[0027] In this way, the rod-shaped aerosol-generating consumable can be used for an aerosolization session that provides the operator with an experience similar to that of traditional smoking.

[0028] Preferably, the aerosol-generating consumable is a tobacco rod.

[0029] In this way, the tobacco rod can be used in an aerosolization session that provides the operator with an experience similar to traditional smoking.

[0030] Preferably, the heating chamber has a generally rectangular cross-section and defines a generally cubic shaped cavity for receiving the aerosol-generating consumable.

[0031] In this way, the heating chamber can be of compact construction, thereby reducing the overall size of the device.

[0032] Preferably, the aerosol-generating consumable is generally planar in shape.

[0033] In this way, the aerosol-generating substrate is compact, thereby reducing the overall size of the device.

[0034] Preferably, the aerosol-generating consumable product comprises tobacco.

[0035] Embodiments of the present invention will now be described, by way of example only, with reference to the drawings in which: [Brief explanation of the drawings]

[0036] [Figure 1] FIG. 1 is a block diagram of the components of an aerosol generating device. [Figure 2] FIG. 1 is a flow diagram of the steps of an aerosolization session. [Figure 3] FIG. 1 is a circuit diagram of the power system of the aerosol generating device. [Figure 4]4 is a plot of heater temperature versus time, where a first data set represents heater temperature as a function of time in the power system of FIG. 3 including the first voltage converter, and a second data set represents heater temperature as a function of time in the power system of FIG. 3 but without the first voltage converter. [Figure 5] 4 is a plot of preheat time as a function of current limit value for the second voltage converter in the power system of FIG. 3. [Figure 6A] 4 is a plot of power versus supercapacitor voltage in the power system of FIG. 3 when the second voltage converter uses output current control. [Figure 6B] 4 is a plot of power versus supercapacitor voltage in the power system of FIG. 3 when the second voltage converter uses input current control. [Figure 7] 1 is a plot of supercapacitor losses as a function of supercapacitor voltage. [Figure 8A] 4 is a plot of heater voltage as a function of time for the power system of FIG. 3 when input current limiting is not used in the second voltage converter. [Figure 8B] 4 is a plot of heater voltage as a function of time for the power system of FIG. 3 when input current limiting is used in the second voltage converter. [Figure 9A] 4 is a plot of current measured at a second power module as a function of time in the power system of FIG. 3 when input current limiting is not used at the second voltage converter. [Figure 9B] 4 is a plot of current measured at a second power module as a function of time in the power system of FIG. 3 when input current limiting is used in the second voltage converter. [Figure 10A] 4 is a plot of the voltage measured at the first power module as a function of time in the power system of FIG. 3 when input current limiting is not used in the second voltage converter. [Figure 10B]4 is a plot of the voltage measured at the first power module as a function of time in the power system of FIG. 3 when input current limiting is used in the second voltage converter. [Figure 11A] 4 is a plot of current measured at a first power module as a function of time in the power system of FIG. 3 when input current limiting is not used at the second voltage converter. [Figure 11B] 4 is a plot of current measured at a first power module as a function of time in the power system of FIG. 3 when input current limiting is used at a second voltage converter. [Figure 12A] FIG. 1 is a diagram of a planar aerosol-generating consumable. [Figure 12B] FIG. 12B is a diagram of the aerosol-generating consumable of FIG. 12A inserted into a heating chamber. [Figure 12C] 12B is a view of the mouthpiece region of an aerosol generating device with a heating chamber of FIG. 12B configured to receive the planar aerosol generating consumable of FIG. 12A. DETAILED DESCRIPTION OF THE INVENTION

[0037] 1 shows a block diagram of the components of an aerosol generating device 100 or vapor generating device, also known as an e-cigarette. For the purposes of this description, the terms "vapor" and "aerosol" should be understood to be synonymous.

[0038] The aerosol generating device 100 comprises a body portion 112 that houses a controller 102 and a power system that comprises a first power module 104 and a second power module 106. The power system is discussed in more detail with respect to FIG.

[0039] Although only one first power module 104 and one second power module 106 are mentioned herein, those skilled in the art will understand that a power system may include one or more first power modules and one or more second power modules as desired.

[0040] The controller 102 is configured to control the power flow of the first power module 104 and the second power module 106 based on the operating mode of the aerosol generating device, as described below.

[0041] The controller 102 may be at least one microcontroller unit having a memory storing instructions for operating the aerosol generating device 100, such as instructions for implementing selectable operating modes and instructions for controlling power flow, and one or more processors configured to execute the instructions.

[0042] In one example, the heater 108 (or heater component) is housed in the body portion 112. In such an example, as shown in FIG. 1 , the heater 108 is disposed in a heating chamber 110 or cavity in the body portion 112. The heating chamber 110 is accessed by an opening 110A in the body portion 112. The heating chamber 110 is positioned to receive an associated aerosol-generating consumable 114. The aerosol-generating consumable may include an aerosol-generating material, such as a tobacco rod containing tobacco. The tobacco rod may be similar to a traditional cigarette. The heating chamber 110 may have a generally cross-sectional shape that may define a generally cylindrical cavity for receiving the aerosol-generating consumable 114.

[0043] The cross-section of the heating chamber 110 is approximately equal to the cross-section of the aerosol-generating consumable 114, and the depth of the heating chamber 110 is such that when the associated aerosol-generating consumable 114 is inserted into the heating chamber 110, a first end 114A of the aerosol-generating consumable 114 reaches the bottom 110B of the heating chamber 110 (i.e., the end 110B of the heating chamber 110 distal from the opening 110A of the heating chamber), and a second end 114B of the aerosol-generating consumable 114 distal from the first end 114A extends outward from the heating chamber 110. In this manner, a consumer can inhale the aerosol-generating consumable 114 when it is inserted into the aerosol-generating device 100. 1, the heater 108 is positioned in the heating chamber 110 such that when the aerosol-generating consumable 114 is inserted into the heating chamber 110, the aerosol-generating consumable 114 engages the heater 108. In the example of FIG. 1, the heater 108 is positioned as a tube within the heating chamber such that when a first end 114A of the aerosol-generating consumable is inserted into the heating chamber, the heater 108 substantially or completely surrounds the portion of the aerosol-generating consumable 114 within the heating chamber 110. The heater 108 may be a wire, such as a coiled wire heater, or a ceramic heater, or any other suitable type of heater. The heater 108 may comprise multiple heating elements that can be independently activated (i.e., powered on) in a sequential order along the axial length of the heating chamber.

[0044] In an alternative embodiment (not shown), the heater may be disposed within the heating chamber as an elongated penetrating member (e.g., a needle, rod, blade, etc.), and in such an embodiment, the heater may be configured to penetrate the aerosol-generating consumable and engage the aerosol-generating material when the aerosol-generating consumable is inserted into the heating chamber.

[0045] In another alternative embodiment (not shown), the heater may be in the form of an induction heater. In such an embodiment, a heating element (i.e., a susceptor) may be provided on the consumable, and when the consumable is inserted into the heating chamber, the heating element is inductively coupled to an induction element (i.e., an induction coil) in the heating chamber. The induction heater then heats the heating element by induction.

[0046] The heater 108 is configured to heat the aerosol-generating consumable 114 to a predetermined temperature to generate an aerosol during an aerosolization session. An aerosolization session can be considered as operating the device to generate an aerosol from the aerosol-generating consumable 114. In examples where the aerosol-generating consumable 114 is a tobacco rod, the aerosol-generating consumable 114 includes tobacco. The heater 108 is configured to heat the tobacco to generate an aerosol without burning the tobacco. That is, the heater 108 heats the tobacco to a predetermined temperature below the combustion point of the tobacco so that a tobacco-based aerosol is generated. It will be readily apparent to those skilled in the art that the aerosol-generating consumable 114 does not necessarily have to include tobacco, and any other substance suitable for aerosolization (or vaporization), particularly heating without burning the substance, can be used in place of tobacco.

[0047] Alternatively, the aerosol-generating consumable may be a vaporizable liquid, which may be contained in a cartridge container receivable within the aerosol-generating device, or which may be injected directly into the aerosol-generating device.

[0048] The controller 102 is configured to control the power flow of the first power module 104 and the second power module 106 based on a selected operating mode of the aerosolization operation. The operating modes of an aerosolization session can include a preheating mode and a heating mode. The progression from the preheating mode to the heating mode in an aerosolization session can be understood from FIG. 2.

[0049] In the preheat mode 202, the heater 108 associated with the aerosol generating device 100 is heated to a predetermined temperature for generating an aerosol from the aerosol-generating consumable 114. The preheat phase can be considered the time during which the preheat mode is performed, e.g., the time it takes for the heater 108 to reach the predetermined temperature. The preheat mode occurs during a first period of an aerosolization session. In one example, the first period can be a fixed, predetermined period. In another example, the first period can vary, corresponding to the length of time required to heat the heater 108 to the predetermined temperature.

[0050] Once the heater reaches the predetermined temperature, the controller 102 terminates the preheat mode 202 and controls the power system to execute the heating mode 204. In the heating mode 204, the controller 102 controls the flow of power from the power system to maintain the heater 108 substantially at the predetermined temperature to generate an aerosol for inhalation by the consumer. The heating phase can be considered the time during which the heating mode is executed, for example, the time during which the heater 108 aerosolizes one aerosol-generating consumable 114 (or at least a portion of one aerosol-generating consumable 114) after the preheat phase. The controller 102 can control the power system to operate the heating mode for a second period of the aerosolization session. The second period can be predetermined and stored in the controller 102.

[0051] In the preheat mode and the heating mode, the controller 102 may control the power flow from the power system to the heater such that the power flow is pulse-width modulated, having one or more pulse-width modulated cycles. A pulse-width modulated power flow includes one or more pulse-width modulated (PWM) cycles (also known as pulse-width modulated switching periods). A single PWM cycle or switching period includes one PWM cycle "on period" D and one PWM cycle "off period" 1-D. The combination of the PWM cycle on period D and the PWM cycle off periods 1-D forms the overall PWM cycle or switching period.

[0052] During the PWM on period of a PWM cycle, power is applied to the heater, i.e., the power line to the heater is closed by a switch implementing PWM control. During the PWM off period, power is not applied to the heater, i.e., the power line to the heater is open by a switch implementing PWM control. Thus, one pulse width modulation cycle comprises one switching of power between an on state and an off state, and thus pulse width modulated power flow comprises a continuous supply of power to the heater with the power flow rapidly switched between PWM on and off periods by the duty cycle.

[0053] The pulse-width modulated duty cycle corresponds to the percentage of the on-time (D) of the total duration of the cycle (D+(1-D)) (i.e., the combined duration of the "on-time" and "off-time" of the switching period). A pulse-width modulated power flow comprising multiple PWM cycles continuously powers the heater with an average power between the PWM on-time and PWM off-time based on the duty cycle. Controlling the duty cycle controls the amount of power delivered to the heater. A higher duty cycle of the pulse-width modulated power flow delivers higher average power, and a lower duty cycle of the pulse-width modulated power flow delivers lower average power. That is, a higher duty cycle results in a greater percentage of the "on-time" D of the cycle than a lower duty cycle. In this manner, careful control of the level of power applied to the heater can be achieved by controlling the duty cycle of the pulse-width modulated power flow.

[0054] In the heating mode, the controller 102 is configured to control the power system to apply a pulse-width modulated power flow to the heater in a first duty cycle regime to maintain the heater substantially at a predetermined aerosol-generating temperature. In the preheat mode, the controller 102 is configured to control the power system to apply a pulse-width modulated power flow to the heater in a second duty cycle regime different from the first duty cycle regime to heat the heater to the aerosol-generating temperature. The second duty cycle regime can have a higher duty cycle than the first duty cycle regime, such that more power is applied to the heater to rapidly heat the heater to the predetermined temperature, while less power is used to maintain the heater at the predetermined temperature. The first duty cycle regime includes one or more PWM cycles having a first duty cycle ratio D1, and the second duty cycle regime includes one or more PWM cycles having a second duty cycle ratio D2, where the relationship between D1 and D2 can be considered to be D2 = D1 * K, where K is a factor >>1 that can be selected as an implementation choice. The theoretical maximum duty cycle is 1 with no off-periods, or close to but less than 1 with very short off-periods. In an example, the first duty cycle regime includes one or more duty cycles with a duty cycle ratio much less than 1, and the second duty cycle regime includes one or more duty cycles with a duty cycle ratio close to but less than 1. In another example, the first duty cycle regime includes one or more duty cycles with a duty cycle ratio << 0.5, and the second duty cycle regime includes one or more duty cycles with a duty cycle ratio ≥ 0.5. In a further example, the first duty cycle is configured to apply <3 W in the heating mode and the second duty cycle is configured to apply approximately 16 W in the preheat mode. More typically, 2 W to 6 W can be applied during the heating mode and 10 W to 30 W can be applied during the preheat mode.

[0055] FIG. 3 presents a circuit diagram of a power system 300 that may be used in the aerosol generating device described with reference to FIG. 1, or in any other suitable type of aerosol generating device.

[0056] The power system 300 of FIG. 3 includes a first power module 104 and a second power module 106 .

[0057] The first power module 104 may be implemented as a supercapacitor module including one or more supercapacitors. Such multiple supercapacitors may be connected in series in the first power module 104. Connecting multiple smaller supercapacitors in series, rather than using a single larger supercapacitor, is advantageous in allowing for greater design flexibility. In another example, the first power module 104 may be implemented as a battery module including one or more high-power batteries with high power discharge rates, such as lithium titanate (LTO) batteries.

[0058] In a specific example, the first power module 104 may be implemented as a supercapacitor module including two supercapacitors connected in series. The supercapacitors may be conventional types and may each have a voltage of 2.5V, thereby providing a total voltage of 5V to the first power module 104. In another such example, the supercapacitors may each have a voltage of 3V, thereby providing a total voltage of 6V to the first power module 104. In another such example, the supercapacitors may each have a voltage of 3.3V, thereby providing a total voltage of 6.6V to the first power module 104. More generally, the supercapacitors may each have a voltage between 2.5V and 3.3V, thereby providing a total voltage of 5V and 6.6V to the first power module 104. In other examples, multiple supercapacitors may be connected in series to meet the voltage requirements needed to power the heater 108.

[0059] The use of one or more supercapacitors or high-power batteries as the first power module 104 is beneficial for powering the energy-intensive pre-heating phase of an aerosolization session due to the high-power characteristics of such components, allowing pre-heating to be achieved quickly.

[0060] The second power module 106 may be implemented as a battery module including one or more batteries. These batteries may be high-energy batteries that store large amounts of energy, such as batteries using lithium-ion, aluminum-ion, or zinc-ion technology, or any other suitable type of battery. Alternatively, the second power module 106 may be implemented as one or more hybrid supercapacitors.

[0061] In a specific example, the second power module 106 may be implemented as a battery module including a lithium-ion battery. Such a battery may have a voltage of 3.7V.

[0062] The use of one or more high-energy batteries or hybrid supercapacitors as the second power module 106 is beneficial for powering multiple aerosolization sessions due to its high energy storage capacity, particularly allowing the second power module 106 to both supplement the power flow from the first power module 104 and recharge the first power module 104 (discussed below).

[0063] The first power module 104 can be connected to the heater 108, for example, in a parallel configuration. The heater 108 need not itself be a component of the power system 300, but rather is powered by the power system 300.

[0064] A first voltage converter 310 is disposed between the first power module 104 and the heater 108. The first voltage converter 310 may be a DC / DC voltage converter with a small minimum voltage input and may be configured to step up or boost the voltage of the first power module 104 for power flow from the first power module 104 to the heater 108.

[0065] If the first voltage converter 310 were not included in the power system 300, the first power module 104 would be limited in the amount of available energy because it would be unable to deliver the required power to the heater 108 if the voltage dropped. Therefore, continuous power delivery may not be possible. This may adversely affect the quality of the aerosolization session. The energy content issue could be addressed by oversizing the first power module 104 to have a higher energy content. However, this would result in a larger aerosol generating device, which may be inconvenient for consumers. Including the first voltage converter 310 between the first power module 104 and the heater 108 to boost the voltage of the power flow from the first power module 104 to the heater 108 avoids these issues. That is, the first voltage converter 310 is beneficial because it allows a smaller first power module 104 to be utilized in the power system by boosting the voltage from the first power module 104, while still achieving continuous power delivery to the heater 108. This, in turn, reduces the overall size of the aerosol generating device including the power system. The first voltage converter 310 allows for the use of lower voltages, which helps stabilize power delivery and improve the quality of the aerosolization session.

[0066] This is evidenced by Figure 4, which shows a plot 400 of heater temperature 402 versus time 404, including a first data set 406 and a second data set 408. The first data set 406 represents heater temperature as a function of time for power system 300 including first voltage converter 310 (as described with reference to Figure 3). For comparison purposes, the second data set 408 represents heater temperature as a function of time for the same power system but without first voltage converter 310. For first data set 406, the inclusion of the first voltage converter causes the heater temperature to rise more rapidly, reaching the target temperature of 210°C in approximately 27.5 seconds (compared to approximately 40 seconds for second data set 408) and stabilizing at this temperature in approximately 55 seconds (compared to approximately 85 seconds for the second data set).

[0067] Furthermore, by including the first voltage converter 310, the preheat time for an aerosolization session is independent of the current limit of the second voltage converter 312 (described below). Figure 5 shows a plot 500 of the preheat time 502 as a function of the current limit 504 of the second voltage converter 312. As can be seen, the preheat time 504 remains substantially constant at approximately 22 seconds, regardless of changes in the current limit 504 of the second voltage converter 312. Thus, improved control over preheating is achieved, thereby improving the aerosolization session.

[0068] 3, the first power module 104 and the second power module 106 are connected to each other in a power system, for example, in a parallel configuration. The second power module 106 can be configured to charge the first power module 104.

[0069] The controller 102 can control the second power module 106 to recharge the first power module 104. The controller 102 can control the flow of power from the second power module 106 to the first power module 104 after an aerosolization session to recharge the first power module 104. In this way, the first power module 104 is appropriately charged between aerosolization sessions to power the power-intensive preheating phase of the subsequent aerosolization session. Alternatively or additionally, the controller 102 can control the flow of power from the second power module 106 to the first power module 104 during an aerosolization session. In this way, the first power module 104 is recharged during the aerosolization session so that it can power the aerosolization session for a longer period of time. How this control is effected will be discussed later.

[0070] A second voltage converter 312 is disposed between the first power module 104 and the second power module 106. The second voltage converter 312 may be configured to step up the voltage of the power flow from the second power module 106 to the first power module 104 when recharging the first power module 104 from the second power module 106. The second voltage converter 312 may be a DC / DC voltage converter and may be configured to step up or boost the voltage of the second power module 106 for charging the first power module 104 from the second power module 106.

[0071] When both the first power module 104 and the second power module 106 are used to power the heater, the first voltage converter 310 can boost the voltage of the power flow from each of the first power module 104 and the second power module 106. The power flow from the second power module 106 can be boosted by the second voltage converter 312 and then boosted again by the first voltage converter 310. Constant current support can be provided from the second power module 106. Thus, the second voltage converter 312 controls the power flow such that the input current to the second voltage converter 312 from the second power module 106 is constant. Depending on the state of the first power module 104, this can mean both boosting the voltage of the second voltage converter 312 (when the first power module 104 is relatively full) or lowering it (when the first power module 104 is relatively empty and a very high current charge is not desired). The first voltage converter 310 can manage the power flow to the heater 108. A small portion of the current from the second power module 106 can flow to the heater 108 (while the majority recharges the first power module 104). As the resistance of the heater 108 increases during an aerosolization session, the first voltage converter 310 needs to continuously boost the voltage. The power delivery can be varied by changing the duty cycle (low power, low duty cycle).

[0072] A first switching means 320 (or first switch) is disposed between the power system (i.e., the first power module 104 and the second power module 106) and the heater 108. This first switching means 320 may be configured to switch the flow of power from the power system to the heater 108 such that when the first switching means 320 is in a closed state, power flows to the heater 108, and when the first switching means 320 is in an open state, power does not flow to the heater 108. The first switching means 320 may be used to either switch off the heater 108 or to control the power flow to the heater 108 using PWM to control the heater temperature.

[0073] A second switching means 322 (or second switch) may optionally be disposed between the second power module 106 and the second voltage converter 312. The second switching means 322 may be configured to control the flow of power from the second power module 106 to the first power module 104 to charge the first power module 104. The second switching means 322 may also be configured to control the flow of power from the second power module 106 to the heater 108 in examples where the second power module 106 contributes to powering the heater 108. In some examples, it is not necessary to include the second switching means 322, for example, because size considerations of the second power module 106 and the first power module 104 mean that the second power module 106 can always support the first power module 104.

[0074] The first switching means 320 and the second switching means 322 may be transistors connected to the controller 102 (not shown in FIG. 5A).

[0075] As described above, the second power module 106 can be configured and controlled to recharge the first power module 104 .

[0076] In some examples, the second power module 104 can be controlled to recharge the first power module 106 after an aerosolization session. This can be caused by the controller 102 controlling the first switching means 320 to open, thereby preventing power from flowing to the heater 108, and controlling the second switching means 322 to close, thereby allowing power to flow from the second power module 106 to the first power module 104, thereby recharging the first power module 104.

[0077] In another example, in addition to or instead of charging the first power module 104 between aerosolization sessions, PWM control can be used to control the second power module 106 to recharge the first power module 104 during an aerosolization session.

[0078] In a first example of the second power module 106 charging the first power module 104 during an aerosolization session, the second power module 106 charges the first power module 104 during both the preheat mode and the heating mode. During the on period of a PWM cycle of PWM power flow to the heater 108, the first power module 104 (or both the first power module 104 and the second power module 106) powers the heater 108. During the off period of a PWM cycle of PWM power flow to the heater 108, the second power module 106 recharges the first power module 104. In a second example of the second power module 106 charging the first power module 104 during an aerosolization session, the second power module 106 charges the first power module 104 during the heating mode, as described in the previous example. However, during the preheat mode, the second power module 106 does not charge the first power module 104. Because a higher duty cycle is used in the preheat mode, not charging the first power module 104 during the preheat mode reduces system complexity.

[0079] An exemplary manner for causing this charging during an aerosolization session may include the controller 102, the first switching means 320, and the second switching means 322 controlling the heating and charging. During an on period of a PWM cycle of the pulse-width modulated power flow, the controller 102 controls the first switching means 320 to close and the second switching means 322 to open. In this manner, power flows from the first power module 104 to the heater 108 during the PWM on period, while the second power module 106 is decoupled from the first power module 104 and the heater 108. During an off period of a PWM cycle of the pulse-width modulated power flow, the controller 102 controls the first switching means 320 to open and the second switching means 322 to close. In this manner, power flows from the second power module 106 to the first power module 104 to recharge the first power module 104, while decoupling the first power module 104 from the heater 108. Thus, during pulse width modulated power flow, rapid switching occurs between powering the heater 108 during the ON period of the PWM cycle and recharging the first power module 104 during the OFF period of the PWM cycle.

[0080] In some examples, the heater 108 is powered only by the first power module 104 during an aerosolization session. In such examples, while power flows from the first power module 104 to the heater 108, the second power module 106 is decoupled from the heater 108 (e.g., using the second switching means 322), and the first switching means 320 is controlled to switch the power flow from the first power module 104 to the heater 108. In such examples, the second power module 106 is used to recharge the first power module 104, either between or during aerosolization sessions, as discussed.

[0081] However, in other examples, during an aerosolization session, the heater 108 may be powered by both the first power module 104 and the second power module 106. In such examples, the second power module 106 supports the first power module 104 during the preheating and / or heating phases. The second voltage converter 312 may be advantageously configured to improve the support provided by the second power module 106 to the first power module 104. This may be achieved by controlling the second voltage converter 312 using input current control, also known as input current limiting. Input current control controls the current limit at the input of the second voltage converter 312, rather than output current control, in which the output current of the voltage converter is controlled.

[0082] To understand the beneficial effects of controlling the second voltage converter 312 using input current control as compared to output current control, refer to Figures 6A and 6B. In the example of Figures 6A and 6B, the first power module 104 can be considered a supercapacitor and the second power module 106 can be considered a battery. However, the same teachings can also be applied to the first power module 104 being any of the other examples described herein and the second power module 106 being any of the other examples described herein.

[0083] By using input current control to control the second voltage converter 312, the second power module 106 can be made less robust or powerful depending on the design energy source. The limit from the input current control helps protect the second power module 106, for example, to ensure that the second power module 106 never draws a higher current than allowed. It also protects alternative energy sources to the second power module, such as a USB port, AA batteries, or a power adapter. The first power module 104 does not need such protection because it can be inherently more robust and powerful.

[0084] 6A shows a plot 600A of power 602A versus supercapacitor voltage 604A when the second voltage converter 312 uses output current control. A first data set 606A corresponds to the power output from the supercapacitor (i.e., first power module 104) as a function of the supercapacitor voltage (i.e., first power module voltage). A second data set 608A corresponds to the power output from the second voltage converter 312 as a function of the supercapacitor voltage (i.e., first power module voltage). If the voltage at the output from the second voltage converter 312 decreases, for example due to a decrease in the voltage of the battery or second power module 106, then the power will decrease as well. Because the output current needs to be kept constant, P output =I output (constant)*V output (This decreases linearly, since the discharge curve of a supercapacitor is also linear.) In this case, a certain power is needed for the heater, and the second power module 106 and second voltage converter 312 cannot deliver it, so more is drawn from the supercapacitor or first power module 104, leading to a higher voltage and higher power output from the supercapacitor or first power module 104. Furthermore, the low internal resistance of the supercapacitor further facilitates this.

[0085] 6B shows a plot 600B of power 602B versus supercapacitor voltage 604B when the second voltage converter 312 uses input current control. A first data set 606B corresponds to the power output from the supercapacitor (i.e., the first power module 104) as a function of the supercapacitor voltage (i.e., the first power module voltage). A second data set 608B corresponds to the power output from the second voltage converter 312 as a function of the supercapacitor voltage (i.e., the first power module voltage). The power output from the second voltage converter 312 (i.e., the power from the battery or second power module 106) is constant due to the input current control. This is because the input current control forces the battery or second power module 106 to continuously support power to the heater 108 by continuously providing the maximum power required from the battery or second power module 106. Therefore, the supercapacitor (i.e., the first power module) also provides a constant output so that the desired power is directed to the heater 108. This stabilizes the power system and reduces losses in the supercapacitor.

[0086] With respect to loss reduction, FIG. 7 shows a plot 700 of supercapacitor losses 702 as a function of supercapacitor voltage 704 for a supercapacitor having an internal resistance of 10 mΩ. A first data set 706 shows supercapacitor losses as a function of supercapacitor voltage when using an input current control limit of 3 A in the second voltage converter 312. A second data set 708 shows supercapacitor losses as a function of supercapacitor voltage when using an output current control limit of 2 A in the second voltage converter 312. As can be seen, supercapacitor losses are significantly lower when using input current control in the second voltage converter 312.

[0087] As a result, higher energy efficiency is achieved, especially at low voltages, helping to utilize more of the energy stored in the supercapacitor. This allows the size of the supercapacitor to be reduced. Input current control allows power division to be independent of the supercapacitor voltage.

[0088] Further advantages of using input current control to control the second voltage converter 312 are discussed with reference to FIGS.

[0089] Figure 8A shows a plot 800A of heater voltage 802A as a function of time 804A when input current limiting is not used in the second voltage converter 312 in the power system 300. Figure 8B shows a plot 800B of heater voltage 802B as a function of time 804B when input current limiting is used in the second voltage converter 312 in the power system 300. As can be seen, the application of input current control does not affect the voltage of the heater 108.

[0090] 9A shows a plot 900A of current 902A measured at the second power module 106 as a function of time 904A when input current limiting is not used at the second voltage converter 312 in the power system 300. FIG. 9A shows a plot 900B of current 902B measured at the second power module 106 as a function of time 904B when input current limiting is used at the second voltage converter 312 in the power system 300. As can be seen, by applying input current limiting, the current level of the second power module 106 is more constant and can be controlled not to exceed a specified maximum current range. Less stress is placed on the second power module 106, thereby improving its life expectancy.

[0091] 10A shows a plot 1000A of the voltage 1002A measured at the first power module 104 as a function of time 1004A when input current limiting is not used at the second voltage converter 312 in the power system 300. FIG. 10B shows a plot 1000B of the current 1002B measured at the first power module 104 as a function of time 1004B when input current limiting is used at the second voltage converter 312 in the power system 300. By applying input current limiting, the first power module 104 sees a smaller voltage drop, which leads to reduced losses and improved stability.

[0092] 11A shows a plot 1100A of the current 1102A measured at the first power module 104 as a function of time 1104A when input current limiting is not used at the second voltage converter 312 in the power system 300. FIG. 11B shows a plot 1100B of the current 1102B measured at the first power module 104 as a function of time 1104B when input current limiting is used at the second voltage converter 312 in the power system 300. As can be seen, by applying input current limiting, the current at the first power module 104 is more constant, thereby placing less stress on the first power module 104.

[0093] The benefits of the second voltage converter 312 are therefore two-fold. First, the second voltage converter 312 advantageously boosts the voltage of the power flow from the second power module 106 to the first power module 104 when charging the first power module 104, allowing a lower voltage of the second power module 106 to be used. Second, the input control of the power flow from the second power module 106 in the second voltage converter 312 reduces losses and stresses in the first power module 104 and reduces stresses in the second power module 106.

[0094] The use of input current control also allows for the use of an external or auxiliary power source, for example, in the event that the energy level of the second power module 106 becomes marginal, or in place of the second power module 106. In a first example, a low-cost power adapter with a low maximum current (e.g., up to 3 A, 5 V) can be used as an external power source to perform an aerosolization session without requiring power from the second power module 106. In a second example, a USB connector, such as from a power bank, car lighter socket, portable PC, stationary PC, etc., can be used in a manner similar to the first example. In a third example, a primary battery (such as three or four AA batteries) can be used as a backup in place of the second power module 106 for the aerosolization session to be performed.

[0095] 3 , the power system 300 may further include a temperature sensor 332 or temperature sensing sub-circuit configured to monitor the temperature of the first power module 104. The power system may also include a temperature sensor 334 or temperature sensing sub-circuit configured to monitor the temperature of the second power module 106. An additional temperature sensor 330 or temperature sensing sub-circuit may be included in the heater 108 to measure the heater temperature or heating chamber temperature. The above-mentioned temperature sensors may be controlled by the controller 102.

[0096] The power system 300 may further include a voltage sensor 342 or voltage sensing sub-circuit configured to monitor the voltage of the first power module 104. The power system may also include a voltage sensor 344 or voltage sensing sub-circuit configured to monitor the voltage of the second power module 106. An additional voltage sensor 340 or voltage sensing sub-circuit may be included in the heater 108 to measure the heater voltage. The above-mentioned voltage sensors may be controlled by the controller 102.

[0097] The power system 300 may further include a current sensor 352 or current sensing sub-circuit configured to monitor the current output by the first power module 104. The power system may also include a current sensor 354 or current sensing sub-circuit configured to monitor the current output by the second power module 106. An additional current sensor 540 or current sensing sub-circuit may be included in the heater 108 to measure the heater current. The above-mentioned current sensors may be controlled by the controller 102.

[0098] The power system 300 may be connected to an external power source, such as a wall mains supply, a battery, a power bank, etc. The external power source may be connected at a connection node 370. The controller 102 may control the charging of the second power module 106 and / or the first power module 104 using a third switching means 324 (or a third switch) between the power system and the connection node 370. In one example, the third switching means 324 may be a transistor switch controlled by the controller 102.

[0099] While the above description has described an aerosol generating device in relation to the aerosol generating device 100 of Figure 1, alternative configurations of aerosol generating devices can readily be used with the power system 300 described in relation to Figure 3. Figures 12A-12C provide an example of an aerosol generating device configured with an alternative heating chamber 1210 for use with an alternative aerosol generating consumable 1214.

[0100] In such alternative embodiments, the aerosol-generating consumable 1214 may have a substantially flat or planar shape. Figures 12A-12C show diagrams of configurations in which such a planar aerosol-generating consumable 1214 and corresponding heating chamber 1210 may be implemented. Figure 12A is a diagram of the planar aerosol-generating consumable 1214, and Figure 12B is a diagram of the aerosol-generating consumable 1214 inserted into the heating chamber 1210. Figure 12C is a diagram of the mouthpiece region of an aerosol generating device comprising a heating chamber 1210 configured to receive such a planar aerosol-generating consumable 1214, with a mouthpiece 1260 attached. The power system 300 described herein, as well as the operation and control of aerosol-generating devices previously described, may also be used with this embodiment of the aerosol-generating device, although these details will not be repeated for the sake of brevity.

[0101] 12A, the aerosol-generating consumable 1214 may have a planar or flat shape, such as the form of a flat rectangular parallelepiped. In a specific example, the length of the consumable 1214 along the axis of the consumable is substantially 33 mm, and the width and depth are substantially 12 mm and 1.2 mm, respectively. That is, the consumable 1214 may be considered planar in shape in that it has a depth that is much shorter than its length and width. However, in other examples, the aerosol-generating consumable 1214 and corresponding heating chamber 1210 may have other suitable shapes or dimensions.

[0102] The aerosol-generating consumable 1214 may include a heating portion 1239 and a mouthpiece portion 1238. The heating portion 1239 is received in the heating chamber 1210, and the mouthpiece portion 1238 is received in the mouthpiece 1260. That is, the heating portion 1239 defines an abutting end of the consumable 1214 that may abut or be adjacent to the bottom 1250 of the heating chamber 1210, and the mouthpiece portion 1238 defines a mouth end of the consumable 1214.

[0103] The heating portion 1239 is configured to be heated by the heater 1208 in the heating chamber 1210 and contains an aerosol-generating material. The aerosol-generating material can be, for example, a material that may include nicotine or tobacco and an aerosol-forming agent. The tobacco can be in the form of various materials, such as cut tobacco, granulated tobacco, tobacco leaf, and / or reconstituted tobacco. Suitable aerosol-forming agents include polyols such as sorbitol, glycerol, and glycols such as propylene glycol or triethylene glycol; monohydric alcohols; acids such as lactic acid; glycerol derivatives; esters such as triacetin; and non-polyols such as triethylene glycol diacetate, triethylene citrate, glycerin, or vegetable glycerin. In some embodiments, the aerosol-generating agent can be glycerol, propylene glycol, or a mixture of glycerol and propylene glycol. The consumable 1214 can also include at least one of a gelling agent, a binder, a stabilizer, and a humectant. When the aerosol-generating material is heated, an aerosol or vapor is formed.

[0104] The mouthpiece portion 1238 is adapted to be received in the mouthpiece 1260. The mouthpiece portion 1238 comprises a core 1264 that may provide a filtering function. In some examples, the core 1264 may be foam or a bundle of fiber strands. The mouthpiece portion 1238 may have a plurality of vent holes 1262 disposed in the wall of the consumable 1214 to allow fresh air to enter the interior of the consumable 1214 to achieve a particular vaping / tasting effect.

[0105] 12C , mouthpiece 1260 has a through-hole designed to receive mouthpiece portion 1238 of aerosol-generating consumable 1214. The through-hole may have the same cross-sectional shape as aerosol-generating consumable 1214 and may have internal dimensions slightly larger than the external dimensions of mouthpiece portion 1238 of aerosol-generating consumable 1214. As can be seen, mouthpiece 1260 fits over mouthpiece portion 1238 of aerosol-generating consumable 1214 that extends from heating chamber 1210 such that the opening in mouthpiece 1260 coincides with the end of aerosol-generating consumable 1214 through which generated aerosol is drawn when an operator inhales into mouthpiece 1260.

[0106] In some cases, the consumable 1214 may not include a vent 1262, in which case air may flow into the consumable 1214 by being drawn in through the abutment end. For example, air may be drawn into the device through an inlet 1266 in the mouthpiece 1260 or through a sidewall of the device to counteract the pressure drop caused by an inhaling operator inhaling on the mouthpiece 1260.

[0107] 12B, the heating chamber 1210 may be cup-shaped having an open end 1248 into which the aerosol-generating consumable 1214 is inserted and an opposite sealed end 1250. The heating chamber 1210 receives the heating portion 1239 of the aerosol-generating consumable 1214. The heating chamber 1210 has substantially the same cross-sectional shape as the aerosol-generating consumable 1214. That is, the heating chamber 1210 may have a generally rectangular cross-section defining a generally cubic-shaped cavity for receiving the planar aerosol-generating consumable 1214.

[0108] The walls of the heating chamber 1210 may have one or more heating elements of the heater 1208 therein or thereon. Each or more of the walls of the heating chamber 1210 may have a heating element therein or thereon.

[0109] The walls of the heating chamber 1210 can be ceramic with heater wires or tracks embedded therein or thereon. In one example, a heating element can be positioned in contact with one of the heating chamber walls on the exterior of the heating chamber 1210. As shown in the example of FIG. 12B, the heating element can be positioned on the exterior surface of the chamber wall. Similarly, a second heating element can be positioned on the exterior surface of the opposing chamber wall (not shown). Thus, the chamber wall transfers heat from the heating element to the aerosol-generating consumable 1214. In another example, the heating element can be embedded in the chamber wall. In a further example, the heating element can be on a chamber wall inside the heating chamber 1210. As described, the chamber walls can be ceramic material with heater tracks or wires embedded therein or thereon. In an alternative form, each heating element can comprise a polyimide film heater that extends along substantially the entire area of ​​the exterior surface of the corresponding heating wall, or along only a portion of this surface.

[0110] In a preferred example, the heating chamber 1210 has two large inner surfaces corresponding to the wide sides of the planar aerosol-generating consumable 1214 and two small inner surfaces corresponding to the narrow sides of the planar aerosol-generating consumable 1214. The small inner surfaces may be perpendicular to and connect the large inner surfaces. The walls of the heating chamber 1210 corresponding to the large inner surfaces may be arranged to form two ceramic heaters with heater wires or tracks embedded therein or thereon. In some examples, the walls of the heating chamber 1210 corresponding to the small inner surfaces may also be ceramic. Such ceramic heaters may provide a compact heating chamber 1210 in which heat directed toward the planar aerosol-generating consumable 1214 is well-distributed. However, such ceramic heaters may require significantly more power for heating (e.g., >>10 W and / or >>1600 J) than heaters in aerosol-generating devices configured to accept more traditional cigarettes or cigarette-like consumables. Therefore, such heaters would greatly benefit from heating power management utilizing one or more supercapacitors or high-power batteries, as described herein.

[0111] In another example, each of the walls may be made from a thermally conductive material, such as metal, in particular stainless steel. Additionally, at least some of the walls or all of these walls may form one single piece.

[0112] The interior dimensions of the heating chamber 1210 may be defined such that when the aerosol-generating consumable 1214 is inserted into the heating chamber 1210, an airflow channel is formed between the walls of the heating chamber 1210 and the walls of the aerosol-generating consumable 1214. That is, when the heating portion 1239 of the aerosol-generating consumable 1214 is inserted into the heating chamber 1214, an airflow channel is formed along the axial length of the consumable 1210.

[0113] As will be readily understood by those skilled in the art, the preceding embodiments in the above description are not limiting, and the features of each embodiment may be incorporated into other embodiments as needed.

[0114] In the above examples, the processing steps described herein performed by the controller 102 or control electronics may be stored in non-transitory computer-readable media or storage associated with the respective controller or control electronics. Computer-readable media may include non-volatile media and volatile media. Volatile media may include semiconductor memory and dynamic memory, among others. Non-volatile media may include optical and magnetic disks, among others.

Claims

1. A power system for an aerosol generating device, wherein the power system is A first power module which is a supercapacitor module containing one or more supercapacitors, The second power module, A first voltage converter is connected between the first power module and the heater component of the aerosol generating device and configured to boost the voltage of the power flow from the first power module to the heater component, A second voltage converter connected between the second power module and the first power module, A power system for an aerosol generating device, comprising the above components.

2. The power system for an aerosol generating device according to claim 1, wherein the second voltage converter is controlled using input current control.

3. The power system for an aerosol generating device according to claim 2, wherein the second voltage converter uses the input current control to supply substantially constant power from the second power module and the first power module to the heater component in accordance with the voltage of the first power module.

4. The power system for the aerosol generating device according to claim 2 or 3, wherein the power system for the aerosol generating device is connectable to an auxiliary power source, and the input current control in the second voltage converter controls the power flow from the auxiliary power source to the heater component for the aerosolization session.

5. The power system for an aerosol generating device according to claim 1, wherein the second power module is configured to recharge the first power module.

6. The power system for an aerosol generating device according to claim 5, wherein the second voltage converter is configured to boost the voltage of the power flow from the second power module to the first power module when the second power module is recharging the first power module.

7. The power system for an aerosol generating device according to claim 1, wherein the second power module is a battery module including at least one battery, or the second power module is a supercapacitor module including one or more supercapacitors, or the second power module is a supercapacitor module including one or more hybrid supercapacitors.

8. An aerosol generating device comprising the power system for the aerosol generating device described in claim 1.

9. The aerosol generating device according to claim 8, further comprising a heating chamber configured to receive aerosol generating consumables and to generate aerosols by heating the aerosol generating consumables without burning them during an aerosolization session.

10. The aerosol generating device according to claim 9, wherein the heating chamber has a substantially circular cross-section and defines a substantially cylindrical cavity for receiving the aerosol generating consumables.

11. The aerosol generating device according to claim 10, wherein the aerosol generating consumable is a tobacco rod.

12. The aerosol generating device according to claim 9, wherein the heating chamber has a substantially rectangular cross-section and defines a substantially cubic cavity for receiving the aerosol generating consumables.

13. The aerosol generating device according to claim 12, wherein the aerosol generating consumable has a substantially planar shape.

14. The aerosol generating device according to any one of claims 9 to 13, wherein the aerosol generating consumable includes a cigarette.

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