WO2024132921A1 - Aerosol generating device - Google Patents

Abstract

An aerosol generating device comprising a heater, a power source and memory comprising firmware The power source is configured to supply power to the heater. The firmware is configured to control the application of power to the heater in a lower heater mode and a higher heater mode, wherein the lower heater mode has a lower mode temperature profile with a lower mode target temperature and the higher heater mode has a higher mode temperature profile with a higher mode target temperature. The firmware includes a control loop comprising a PID controller. The PID controller is configured to receive a temperature signal indicative of a measurement of the temperature of the heater, calculate, using the temperature signal, a PID controller output, and output the PID controller output. The control loop is configured to control, based on the PID controller output, a power applied to the heater from the power source to thereby regulate the temperature of the heater to a respective one of the lower mode or higher mode target temperatures.

Description

AEROSOL GENERATING DEVICE

This application claims priority from EP22214707.6 filed 19 December 2022, the contents and elements of which are herein incorporated by reference for all purposes.

FIELD

The present disclosure relates to an aerosol generating device, and more particularly, though not exclusively to an aerosol generating device for provision of an aerosol to a user for inhalation.

BACKGROUND

A typical aerosol generating device I apparatus, or smoking substitute apparatus I device, may comprise a power supply, an aerosol generating unit that is driven by the power supply, an aerosol precursor, which in use is aerosolised by the aerosol generating unit to generate an aerosol, and a delivery system for delivery of the aerosol to a user. The aerosol is delivered to the user for inhalation by the user. The aerosol generating unit is, in some cases, a heater, which heats the aerosol precursor to form the aerosol. In such examples, the heater and the aerosol precursor are in thermal contact with one another, to allow the heating for aerosol formation. In some examples, the aerosol precursor is provided as a consumable, or as part of a consumable. The consumable is a separate unit from the aerosol generating device. The aerosol generating device includes the heater. The aerosol generating device and consumable are mutually engaged with one another. Such engagement brings the heater into thermal contact with the aerosol precursor, for heating. The temperature of the heater is controlled, to, in turn, control the heating of the aerosol precursor. Accurate temperature control is important.

A drawback with known aerosol generating apparatuses is that the temperature of the heater may be poorly controlled. Further, it may take a non-negligible amount of time for the heater to heat the aerosol precursor to a temperature at which a sufficient amount of aerosol is generated.

In spite of the effort already invested in the development of aerosol generating apparatuses/systems further improvements are desirable.

SUMMARY

The present disclosure provides an aerosol generating device that comprises a heater, a power source configured to supply power to the heater, and a memory comprising firmware, the firmware configured to control the application of power to the heater in a heater mode, wherein the heater mode has a temperature profile with a target temperature.

The firmware may control the application of powerto the heater when the firmware is run by a processing resource of the aerosol generating device, such as a microcontroller. The firmware may be stored on a permanent, or non-transitory, memory of the aerosol generating device. The permanent memory may be a read-only memory (ROM).

In some examples, the target temperature is saved in a memory of the aerosol generating device. In some examples, a value derived from the target temperature is saved in a memory of the aerosol generating device. For example, a target resistance of the heater derived from the target temperature may be saved in a memory of the aerosol generating device. For example, a value representative of a target resistance or target temperature of the heater derived from the target temperature may be saved in a memory of the aerosol generating device. The memory may be a permanent memory, which may be a ROM.

In some examples, the temperature profile is saved in a memory of the aerosol generating device. In some examples, a profile derived from the temperature profile may be saved in a memory of the aerosol generating device. For example, a resistance profile for the heater may be saved in a memory of the aerosol generating device. The memory may be a permanent memory, which may be a ROM.

The power source may be a battery.

The heater may be a resistive heater.

In some examples, the aerosol generating device may be a heat-not-burn aerosol generating device.

In some examples, the firmware may be configured to control the application of power to the heater in a lower heater mode and in a higher heater mode, wherein the lower heater mode has a lower mode temperature profile with a lower mode target temperature and the higher heater mode has a higher mode temperature profile with a higher mode target temperature.

In this way, the aerosol generating device may be configured to operate in two heater modes.

In some examples, each of the lower heater mode and the higher heater mode may be selectable by a user of the aerosol generating device. For example, the lower heater mode may be selectable through a mode selection input device, which may be a mode selection actuator, for example a button. The lower heater mode may be selectable by a pre-determined interaction with the mode selection input device, which may be, for example, a pre-determined number of button presses, or a pre-determined duration of a button press. The higher heater mode may be selectable through a mode selection input device, which may be a mode selection actuator, for example a button. The higher heater mode may be selectable by a pre-determined interaction with the mode selection input device, which may be, for example, a pre-determined number of button presses, or a pre-determined duration of a button press. The mode selection input device may be the same for the lower heater mode and the higher heater mode. The pre-determined interaction with the mode selection input device may be different for the lower heater mode and the higher heater mode. For example, the pre-determined number of button presses may be different for the lower heater mode and the higher heater mode, or the pre-determined duration of the button press may be different for the lower heater mode and the higher heater mode. The lower heater mode and the higher heater mode may be selectable by different mode selection input device. For example, the lower heater mode may be selectable by a lower mode button, and the higher heater mode may be selectable by a higher mode button.

In some examples, the firmware configured to control the application of power to the heater may be configured to start running upon receiving a signal from the the mode selection input device. In some examples, a control loop may be configured to start running upon receiving a signal from the mode selection input device.

In some examples, the firmware may include a control loop comprising a PID controller, the PID controller configured to receive a temperature signal indicative of a measurement of the temperature of the heater, calculate, using the temperature signal, a PID controller output, and output the PID controller output, wherein the control loop is configured to control, based on the PID controller output, a power applied to the heater from the power source to thereby regulate the temperature of the heater to the target temperature.

In this way, the temperature of the heater may be precisely regulated to the target temperature.

A PID controller is a proportional-integral-derivative controller. The PID controller may take the temperature signal as an input. The PID controller may take the target temperature as an input. The PID controller may take a value derived from the target temperature as an input. The value derived from the target temperature may have the same units as the units of the temperature signal. In some examples the temperature signal may be a measurement of the resistance of the heater. In some examples, the value derived from the target temperature is a target resistance.

In some examples, the PID controller may be configured to receive a target resistance. The target resistance may correspond to the target temperature for the heater.

In some examples, the control loop may be configured to operate in a repeating cycle with a repetition period.

In this way, the control loop may continuously regulate the temperature of the heater to a target temperature.

In some examples, the repetition period is between 1 millisecond and 50 milliseconds. In some examples, the repetition period is between 10 milliseconds and 30 milliseconds. In some examples, the repetition period is approximately 20 milliseconds. In some examples, the repetition period is 20 milliseconds.

In some examples, the PID controller output is an average power to be applied to the heater in the repetition period to thereby regulate the temperature of the heater to the target temperature. The average power may be the mean power over the repetition period. In some examples, the control by the control loop of the power applied to the heater from the power source may include calculating a heater-on fraction from a power ratio which is the average power divided by a power output of the power source. In some examples, the control by the control loop of the power applied to the heater from the power source may include outputting a power control signal, such that power is applied to the heater from the power source for the heater-on fraction of the repetition period only.

The power control signal may be on signal which causes power to be applied to the heater from the power source. The power control signal may be an off signal which causes substantially zero power to be applied to the heater from the power source.

The heater-on fraction may be referred to as a duty cycle.

Power being applied to the heater from the power source for the heater-on fraction of the repetition period only may result in approximately the average power being applied to the heater over the repetition period. Power being applied to the heater from the power source for the heater-on fraction of the repetition period only may result in the average power being applied to the heater over the repetition period.

In this way, the power applied to the heater from the power source can be controlled. Further, the power applied to the heater from the power source can be controlled, even when the power source is a nonvariable power source. A non-variable power source may mean a power source which is able to output only a constant amount of power when the power source is switched on.

In some examples, the on signal is output at the start of the repetition period. In some examples, the off signal is output after the heater-on fraction of the repetition period.

In some examples, the off signal is output at the start of the repetition period. In some examples, the on signal is output after the heater-off fraction of the repetition period. The heater-off fraction of the repetition period may be 1 minus the heater-on fraction.

In this way, there may be only two signals output in each repetition period. In other words, there may be only one on signal and one off signal output in each repetition period.

In some examples, the heater on fraction may be equal to the power ratio.

In some examples, the repetition period is divided into a plurality of sub-periods of equal length. In some examples, the on signal may be output after an integer number (including zero) of sub-periods. In some examples, the off signal may be output after an integer number (including zero) of sub-periods.

Because the repetition period may be divided into an integer number of sub-periods, the time for which the heater can be turned on within one repetition period may not be arbitrary. Instead, the heater may only be turned on for an integer number of sub-periods (including zero sub-periods or all sub-periods in the repetition period). As such, the heater on fraction may be equal to a number ratio which is an integer number of sub-periods during which the heater is on divided by the total number of sub-periods in the repetition period, where the integer number of sub-periods is calculated such that the number ratio is as close to the power ratio as possible.

In this way, it may be easier to implement the control of the power applied to the heater.

In some examples, the length of each of the plurality of sub-periods may be between 200 microseconds and 500 microseconds. The length of each of the plurality of sub-periods may be approximately 400 microseconds. The length of each of the plurality of sub-periods may be 400 microseconds. The total number of the plurality of sub-periods may be between 10 and 200. The total number of the plurality of sub-periods may be approximately 50. The total number of the plurality of sub-periods may be 50.

In some examples, the control by the control loop of the power applied to the heater from the power source may include setting, when the average power is greater than a threshold power, the average power to be equal to the threshold power. The threshold power may be the maximum power output of the battery.

In some examples, the control by the control loop of the power applied to the heater from the power source may include setting, when the average power is less than zero, the average power to be equal to zero. This step may be carried out by the PID controller.

In this way, the control loop may take into account the maximum and minimum power outputs of the battery.

In some examples, the aerosol generating device comprises a cap movable relative to the body of the aerosol generating device. Moving the cap away from body may expose a portion of the heater.

In this way, it may be easier to clean the heater.

The cap may be referred to as an “extractor”.

In some examples, the control loop is configured to receive a cap position signal indicative of a measured position of the cap relative to the body of the device. The control loop may be configured to output a cap warning signal if the cap position signal indicates that the position of the cap is not in a predetermined position. The cap warning signal may generate an alert presented to a user of the device. The alert may be visual, aural or haptic. The alert may be a light of the device illuminating, a speaker of the device emitting a sound, orthe device vibrating. The control loop may be configured to stop I prevent application of power to the heater if the cap position signal indicates that the position of the cap is in a predetermined position. The predetermined position may be a position in which the heater is at least partially exposed. The heater not being exposed may mean that the heater is surrounded circumferentially by the body and/or cap. The heater not being exposed may mean that the heater is surrounded entirely by the body and/or cap. Advantageously, the safety of the device may be improved.

In some examples, the control loop is configured to receive a power source temperature signal indicative of a measured temperature of the power source. The control loop may be configured to output a high temperature warning signal if the power source temperature signal indicates that the temperature of the power source is over a predetermined high threshold temperature of the power source. The control loop may be configured to output a low temperature warning signal if the power source temperature signal indicates that the temperature of the power source is below a predetermined low threshold temperature of the power source. The high temperature and/or low temperature warning signal may generate an alert presented to a user of the device. The alert may be visual, aural or haptic. The alert may be a light of the device illuminating, a speaker of the device emitting a sound, or the device vibrating. The control loop may be configured to stop if power source temperature signal indicates that the temperature of the power source is over a predetermined high threshold temperature of the power source. The control loop may be configured to stop if power source temperature signal indicates that the temperature of the power source is below a predetermined low threshold temperature of the power source. The low temperature threshold of the power source may be approximately -10°C. The high temperature threshold of the power source may be approximately 50°C.

Advantageously, the safety of the aerosol generating device is improved. Advantageously, the lifetime of the power source of the device may be improved.

In some examples, the control loop is configured to receive a power source voltage signal indicative of a measured voltage output by the power source. The control loop may be configured to output a voltage warning signal if the power source voltage signal indicates that the voltage output by the power source is below a predetermined threshold voltage. The voltage warning signal may cause a low voltage protection operation to be run. The control loop may be configured to stop if the power source voltage signal indicates that the voltage output by the power source is below the threshold voltage. The threshold voltage of the power source may be approximately 3V.

Advantageously, the safety of the aerosol generating device may be improved.

In some examples, the control loop is configured to receive a power source current signal indicative of a measured current output by the power source. The control loop may be configured to output a high current warning signal if the power source current signal indicates that the current output by the power source is over a predetermined high threshold current of the power source. The control loop may be configured to output a low current warning signal if the power source current signal indicates that the current output by the power source is below a predetermined low threshold current of the power source. The high current warning signal may cause a short circuit protection operation to be carried out. The low current warning signal may cause an open circuit protection operation to be carried out. The control loop may be configured to stop if power source current signal indicates that the current output by the power source is over a predetermined high threshold current. The control loop may be configured to stop if power source current signal indicates that the current output by the power source is below a predetermined low threshold current. The low current threshold may be approximately 0.1 A. The high current threshold of the power source may be approximately 5A.

Advantageously, the safety of the aerosol generating device may be improved.

In some examples, the control loop may be configured to stop when the control loop has been running for over approximately 300 seconds. In some examples, the control loop may be configured to stop when the control loop has been running for over 315 seconds. The time which the control loop has been running for may be referred to as a heating time.

Advantageously, power is not wasted by heating the heater for a prolonged period. Advantageously, the lifetime of the power source may be improved.

In some examples, the firmware further comprises initialisation instructions. The firmware may be configured such that, when the firmware is run, the initialisation instructions run before the control loop begins to run.

In some examples, the initialisation instructions may begin to run upon receiving a signal from an input device, which may be an actuator such as a button.

In some examples, the initialisation instructions may include outputting a stop-charging signal to stop the charging of the power source.

In some examples the initialisation instructions may include initialising the parameters of the control loop. The parameters of the control loop may include a cap position, a power source temperature, a power source output voltage and a power source output current. The parameters of the control loop may include the heating time.

In some examples, the initialisation instructions may include receiving a power source voltage signal indicative of a measured voltage output by the power source. The initialisation instructions may be configured to output a voltage warning signal if the power source voltage signal indicates that the voltage output by the power source is below a predetermined threshold voltage. The voltage warning signal may cause a low voltage protection operation to be run. The initialisation instructions may be configured to stop running if the power source voltage signal indicates that the voltage output by the power source is below the threshold voltage. The threshold voltage of the power source may be approximately 3.45 V.

Advantageously, the safety of the device may be improved.

In some examples, the initialisation instructions may include applying a voltage to an op-amp of the aerosol generative device. The voltage applied to the op-amp may be approximately 3V. The voltage applied to the op-amp may be approximately 3.3V. The voltage applied to the op-amp may be 3.3V. The op-amp may be used to amplify a voltage across a resistor in series with the heater to measure the resistance of the heater. In some examples, the target temperature may be the lower mode target temperature or the higher mode target temperature.

Therefore, the control loop may regulate the temperature of the heater to a respective one of the lower mode target temperature or the higher mode target temperature. Further, the PID output may be an average power to be applied to the heater to thereby regulate the temperature of the heater to a respective one of the lower mode or higher mode target temperatures.

In this way, the aerosol generating device may be configured to operate in two heater modes, where the temperature of the heater may be precisely regulated to a respective target temperature of each heater mode.

In some examples, the temperature profile includes a pre-heat phase, an overshoot phase and a primary heating phase, wherein in the pre-heat phase, the target temperature is an overshoot temperature, such that during the pre-heat phase the temperature of the heater increases from an initial temperature to the overshoot temperature, wherein in the overshoot phase, the target temperature is an overshoot temperature, such that during the overshoot phase the temperature of the heater is regulated to the overshoot temperature, and wherein in the primary heating phase, the target temperature is a primary temperature, such that during the primary heating phase the temperature of the heater is regulated to the primary temperature, wherein the overshoot temperature is greater than the primary temperature.

In this way, the temperature of the heater may increase at a faster rate. The heater may heat up from the initial temperature to the primary temperature faster.

Advantageously, the temperature of a precursor within the aerosol generating device may increase at a faster rate. The time between power first being applied to the heater and the aerosol generating device being suitable for use by the user may be reduced.

The initial temperature may be an ambient temperature.

In some examples, in the primary heating phase, the aerosol generating device may be suitable for use by the user. In some examples, in the primary heating phase, aerosol may readily be inhaled by a user.

The primary temperature may be a temperature which is high enough to vaporise a precursor within the aerosol generating device. The primary temperature may be a temperature which is low enough not to burn a precursor within the aerosol generating device. The primary temperature may be between 300°C and 360°C.

In some examples, the difference between the primary temperature and the overshoot temperature may be between 5°C and 40°C. The difference between the primary temperature and the overshoot temperature may be between 10°C and 30°C.

In some examples, the firmware further comprises preheating indicator instructions. The preheating indicator instructions may be configured to receive a heating phase signal indicative of whether the heater is being heated in the pre-heat phase, the overshoot phase or the primary heating phase. In some examples, when the heating phase signal indicates that the heater is being heated in the pre-heat phase or the overshoot phase, the preheating indicator instructions may generate an alert presented to the user of the device. The alert may be a light of the device illuminating or a speaker of the device emitting a sound.

The preheating indicator instructions may be configured to receive a heating phase signal indicative of a phase changing from the overshoot phase to the primary heating phase. In some examples, when the phase signal indicates that phase has changed from the overshoot phase to the primary heating phase, the preheating indicator instructions may generate an alert presented to the user of the device. The alert may be a light of the device illuminating or a speaker of the device emitting a sound.

Advantageously, the user may be prompted only to inhale aerosol from the aerosol generating device when the aerosol generating device is operating with the heater in the primary heating phase.

In some examples, the duration over which the temperature increases between the primary temperature and the overshoot temperature is between 3 seconds and 10 seconds. In some examples, the duration over which the temperature increases between the primary temperature and the overshoot temperature is between 5 seconds and 8 seconds. The duration over which the temperature increases between the primary temperature and the overshoot temperature may depend on the power rating of the power source, the resistance of the heater, and/or the ambient temperature.

In some examples, the duration over which the temperature decreases from the overshoot temperature to the primary temperature is between 3 seconds and 10 seconds. In some examples, the duration over which the temperature decreases from the overshoot temperature to the primary temperature is between 5 seconds and 8 seconds. In some examples, the duration over which the temperature decreases from the overshoot temperature to the primary temperature may depend on the power rating of the power source, the resistance of the heater, and/or the ambient temperature.

In some examples, the duration of the overshoot phase is between 10 seconds and 30 seconds.

In this way, the temperature of a precursor within the aerosol generating device may increase at a faster rate. The time between power first being applied to the heater and the aerosol generating device being suitable for use by the user may be reduced.

In some examples, the duration of the overshoot phase is between 1 second and 3 seconds. In some examples, the duration of the overshoot phase is approximately 0 seconds. In other words, the heater is at the overshoot temperature approximately instantaneously.

In this way, the temperature of the heater may increase at a faster rate.

In some examples, the duration of the overshoot phase may be saved in a memory of the aerosol generating device. The memory may be a permanent memory, which may be a ROM. In some examples, the temperature profile further includes an overshoot decay phase. In the overshoot decay phase, the temperature of the heater may decrease from the overshoot temperature to the primary temperature. The overshoot decay phase may comprise a plurality of stepped decay phases. In each stepped decay phase, the target temperature may be a respective one of a plurality of step temperatures. During each stepped decay phase, the temperature of the heater may decrease.

Advantageously, the temperature of the heater may decrease more gradually. Advantageously, the temperature of the heater may be less likely to undershoot the primary target temperature.

In some examples, there may be between 5 and 20 stepped decay phases. In some examples, there may be between 5 and 50 stepped decay phases. In some examples, there may be between 50 and 200 stepped decay phases.

In some examples, the duration of each of the stepped decay phases is the same.

Advantageously, the overshoot decay phase may be easier to implement. Advantageously, the temperature of the heater may steadily decrease throughout the overshoot decay phase.

In some examples, the duration of each of the stepped decay phases is between 1 second and 15 seconds. The duration of each of the stepped decay phases may be approximately 10 seconds. The duration of each of the stepped decay phases may be approximately 0.1 seconds.

The preheating indicator instructions may be configured to receive a heating phase signal indicative of whether the heater is being heated in the pre-heat phase, the overshoot phase, the overshoot decay phase or the primary heating phase. In some examples, when the heating phase signal indicates that the heater is being heated in the pre-heat phase, the overshoot phase, or the overshoot decay phase, the preheating indicator instructions may generate an alert presented to the user of the device. The alert may be a light of the device illuminating or a speaker of the device emitting a sound.

The preheating indicator instructions may be configured to receive a heating phase signal indicative of a phase changing from the overshoot decay phase to the primary heating phase. In some examples, when the phase signal indicates that phase has changed from the overshoot decay phase to the primary heating phase, the preheating indicator instructions may generate an alert presented to the user of the device. The alert may be a light of the device illuminating or a speaker of the device emitting a sound.

Advantageously, the user may be prompted only to inhale aerosol from the aerosol generating device when the aerosol generating device is operating with the heater in the primary heating phase.

In some examples, the temperature profile may be the lower mode temperature profile, and the preheat phase, the overshoot phase and the primary heating phase may be a lower mode pre-heat phase, a lower mode overshoot phase and a lower mode primary heating phase respectively.

In some examples, the lower mode temperature profile includes a lower mode pre-heat phase, a lower mode overshoot phase and a lower mode primary heating phase, wherein in the lower mode pre-heat phase the lower mode target temperature is a lower mode overshoot temperature, such that during the lower mode pre-heat phase the temperature of the heater increases from an initial temperature to the lower mode overshoot temperature, wherein in the lower mode overshoot phase the lower mode target temperature is a lower mode overshoot temperature, such that during the lower mode overshoot phase the temperature of the heater is regulated to the lower mode overshoot temperature, and wherein in the lower mode primary heating phase the lower mode target temperature is a lower primary temperature, such that during the lower mode primary heating phase the temperature of the heater is regulated to the lower primary temperature, wherein the lower mode overshoot temperature is greater than the lower mode primary temperature.

In some examples, the temperature profile may be the higher mode temperature profile, and the preheat phase, the overshoot phase and the primary heating phase may be a higher mode pre-heat phase, a higher mode overshoot phase and a higher mode primary heating phase respectively.

In some examples, the higher mode temperature profile includes a higher mode pre-heat phase, a higher mode overshoot phase and a higher mode primary heating phase, wherein in higher mode the pre-heat phase the higher mode target temperature is a higher mode overshoot temperature, such that during the higher mode pre-heat phase the temperature of the heater increases from an initial temperature to the higher mode overshoot temperature, wherein in the higher mode overshoot phase the higher mode target temperature is a higher mode overshoot temperature, such that during the higher mode primary phase the temperature of the heater is regulated to the higher mode overshoot temperature, and wherein in the higher mode primary heating phase the higher mode target temperature is a higher primary temperature, such that during the higher mode primary heating phase the temperature of the heater is regulated to the higher primary temperature, wherein the higher mode overshoot temperature is greater than the higher mode primary temperature.

In some examples, the higher mode overshoot temperature is a highertemperature than the lower mode overshoot temperature. In some examples, the higher mode primary temperature is a higher temperature than the lower mode primary temperature. In some examples, the higher mode primary temperature is approximately 345°C. In some examples, the lower mode primary temperature is approximately 315°C.

In this way, the aerosol generating device may operate in two heater modes with different heater temperatures. Advantageously, each of the two heater modes may provide for a different user experience.

In some examples, the duration of the lower mode overshoot phase and the duration higher mode overshoot phase are the same. The duration of the lower mode pre-heat phase and the duration of the higher mode pre-heat phase may be similar or the same. The duration over which the temperature decreases from the higher mode overshoot temperature to the higher mode primary temperature may be similar or the same as the duration over which the temperature decreases from the lower mode overshoot temperature to the lower mode primary temperature. Advantageously, the dual heater mode functionality may be easier to implement.

In some examples, the difference between the higher mode primary temperature and the higher mode overshoot temperature and the difference between the lower mode primary temperature and the lower mode overshoot temperature may be the same.

Advantageously, the dual heater mode functionality may be easier to implement.

In some examples, the overshoot decay phase may be a lower mode overshoot decay phase.

In some examples, the lower mode temperature profile may further include a lower mode overshoot decay phase comprising a plurality of lower mode stepped decay phases, wherein in each lower mode stepped decay phase the lower mode target temperature is a respective one of a plurality of lower mode step temperatures, such that during each lower mode stepped decay phase the temperature of the heater decreases, and such that in the lower mode overshoot decay phase the temperature of the heater decreases from the lower mode overshoot temperature to the lower mode primary temperature.

In some examples, the overshoot decay phase may be a higher mode overshoot decay phase.

In some examples, the higher mode temperature profile may further include a higher mode overshoot decay phase comprising a plurality of higher mode stepped decay phases, wherein in each higher mode stepped decay phase the higher mode target temperature is a respective one of a plurality of higher mode step temperatures, such that during each higher mode stepped decay phase the temperature of the heater decreases, and such that in the higher mode overshoot decay phase the temperature of the heater decreases from the higher mode overshoot temperature to the higher mode primary temperature.

In some examples, the duration of each higher mode stepped decay phase is the same as the duration of each lower mode stepped decay phase. In some examples, the number of higher mode stepped decay phases are the same as the number of each lower mode stepped decay phase.

Advantageously, the dual mode heater functionality may be easier to implement.

The preceding summary is provided for purposes of summarizing some examples to provide a basic understanding of aspects of the subject matter described herein. Accordingly, the above-described features should not be construed to narrow the scope or spirit of the subject matter described herein in any way. Moreover, the above and/or proceeding examples may be combined in any suitable combination to provide further examples, except where such a combination is clearly impermissible or expressly avoided. Other features, aspects, and advantages of the subject matter described herein will become apparent from the following text and the accompanying drawings.

BRIEF DESCRIPTION OF THE FIGURES Aspects, features and advantages of the present disclosure will become apparent from the following description of examples in reference to the appended drawings in which like numerals denote like elements.

Fig. 1 is a block system diagram showing an example aerosol generating apparatus.

Fig. 2 is a block system diagram showing an example implementation of the apparatus of Fig. 1 , where the aerosol generating apparatus is configured to generate aerosol from a liquid precursor.

Figs. 3a and 3b are schematic diagrams showing an example implementation of the apparatus of Fig. 2.

Fig. 4 is a block system diagram showing an example implementation of the apparatus of Fig. 1 , where the aerosol generating apparatus is configured to generate aerosol from a solid precursor.

Fig. 5 is a schematic diagram showing an example implementation of the apparatus of Fig. 4.

Fig. 6 is a block system diagram showing an example system for managing an aerosol generating apparatus.

Fig. 7 is a flowchart showing an example control loop according to an embodiment of the present invention.

Fig. 8 is a flowchart showing an example control loop according to an embodiment of the present invention.

Fig. 9 is a flowchart showing an example of initiation instructions according to an embodiment of the present invention.

Fig. 10 is a flowchart showing an example of initialisation instructions and a control loop according to an embodiment of the present invention.

Fig. 11A is an example of a temperature profile according to an embodiment of the present invention.

Fig. 11 B is an example of heater behaviour according to an embodiment of the present invention.

Fig. 12A is an example of a temperature profile according to an embodiment of the present invention.

Fig. 12B is an example of heater behaviour according to an embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

Before describing several examples implementing the present disclosure, it is to be understood that the present disclosure is not limited by specific construction details or process steps set forth in the following description and accompanying drawings. Rather, it will be apparent to those skilled in the art having the benefit of the present disclosure that the systems, apparatuses and/or methods described herein could be embodied differently and/or be practiced or carried out in various alternative ways.

Unless otherwise defined herein, scientific and technical terms used in connection with the presently disclosed inventive concept(s) shall have the meanings that are commonly understood by those of ordinary skill in the art, and known techniques and procedures may be performed according to conventional methods well known in the art and as described in various general and more specific references that may be cited and discussed in the present specification.

Any patents, published patent applications, and non-patent publications mentioned in the specification are hereby incorporated by reference in their entirety.

All examples implementing the present disclosure can be made and executed without undue experimentation in light of the present disclosure. While particular examples have been described, it will be apparent to those of skill in the art that variations may be applied to the systems, apparatus, and/or methods and in the steps or in the sequence of steps of the methods described herein without departing from the concept, spirit, and scope of the inventive concept(s). All such similar substitutions and modifications apparent to those skilled in the art are deemed to be within the spirit, scope, and concept of the inventive concept(s) as defined by the appended claims.

The use of the term “a” or “an” in the claims and/or the specification may mean “one,” as well as “one or more,” “at least one,” and “one or more than one.” As such, the terms “a,” “an,” and “the,” as well as all singular terms, include plural referents unless the context clearly indicates otherwise. Likewise, plural terms shall include the singular unless otherwise required by context.

The use of the term “or” in the present disclosure (including the claims) is used to mean an inclusive “and/or” unless explicitly indicated to refer to alternatives only or unless the alternatives are mutually exclusive. For example, a condition “A or B” is satisfied by any of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).

As used in this specification and claim(s), the words “comprising, “having,” “including,” or “containing” (and any forms thereof, such as “comprise” and “comprises,” “have” and “has,” “includes” and “include,” or “contains” and “contain,” respectively) are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

Unless otherwise explicitly stated as incompatible, or the physics or otherwise of the embodiments, examples, or claims prevent such a combination, the features of examples disclosed herein, and of the claims, may be integrated together in any suitable arrangement, especially ones where there is a beneficial effect in doing so. This is not limited to only any specified benefit, and instead may arise from an “ex post facto” benefit. This is to say that the combination of features is not limited by the described forms, particularly the form (e.g. numbering) of example(s), embodiment(s), or dependency of claim(s). Moreover, this also applies to the phrase “in one embodiment,” “according to an embodiment,” and the like, which are merely a stylistic form of wording and are not to be construed as limiting the following features to a separate embodiment to all other instances of the same or similar wording. This is to say, a reference to ‘an,’ ‘one,’ or ‘some’ embodiment(s) may be a reference to any one or more, and/or all embodiments, or combination(s) thereof, disclosed. Also, similarly, the reference to “the” embodiment may not be limited to the immediately preceding embodiment. Further, all references to one or more embodiments or examples are to be construed as non-limiting to the claims.

The present disclosure may be better understood in view of the following explanations, wherein the terms used that are separated by “or” may be used interchangeably:

As used herein, an "aerosol generating apparatus" (or “electronic(e)-cigarette”) may be an apparatus configured to deliver an aerosol to a user for inhalation by the user. The apparatus may additionally/alternatively be referred to as a “smoking substitute apparatus”, if it is intended to be used instead of a conventional combustible smoking article. As used herein a combustible “smoking article” may refer to a cigarette, cigar, pipe or other article, that produces smoke (an aerosol comprising solid particulates and gas) via heating above the thermal decomposition temperature (typically by combustion and/or pyrolysis). An aerosol generated by the apparatus may comprise an aerosol with particle sizes of 0.2 - 7 microns, or less than 10 microns, or less than 7 microns. This particle size may be achieved by control of one or more of: heater temperature; cooling rate as the vapour condenses to an aerosol; flow properties including turbulence and velocity. The generation of aerosol by the aerosol generating apparatus may be controlled by an input device. The input device may be configured to be user- activated, and may for example include or take the form of an actuator (e.g. actuation button) and/or an airflow sensor.

Each occurrence of the aerosol generating apparatus being caused to generate aerosol for a period of time (which may be variable) may be referred to as an “activation” of the aerosol generating apparatus. The aerosol generating apparatus may be arranged to allow an amount of aerosol delivered to a user to be varied per activation (as opposed to delivering a fixed dose of aerosol), e.g. by activating an aerosol generating unit of the apparatus for a variable amount of time, e.g. based on the strength/duration of a draw of a user through a flow path of the apparatus (to replicate an effect of smoking a conventional combustible smoking article).

The aerosol generating apparatus may be portable. As used herein, the term "portable" may refer to the apparatus being for use when held by a user.

As used herein, an "aerosol generating system" may be a system that includes an aerosol generating apparatus and optionally other circuitry/components associated with the function of the apparatus, e.g. one or more external devices and/or one or more external components (here “external” is intended to mean external to the aerosol generating apparatus). As used herein, an “external device” and “external component” may include one or more of a: a charging device, a mobile device (which may be connected to the aerosol generating apparatus, e.g. via a wireless or wired connection); a networked-based computer (e.g. a remote server); a cloud-based computer; any other server system. An example aerosol generating system may be a system for managing an aerosol generating apparatus. Such a system may include, for example, a mobile device, a network server, as well as the aerosol generating apparatus.

As used herein, an "aerosol" may include a suspension of precursor, including as one or more of: solid particles; liquid droplets; gas. Said suspension may be in a gas including air. An aerosol herein may generally refer to/include a vapour. An aerosol may include one or more components of the precursor.

As used herein, a “precursor” may include one or more of a: liquid; solid; gel; loose leaf material; other substance. The precursor may be processed by an aerosol generating unit of an aerosol generating apparatus to generate an aerosol. The precursor may include one or more of: an active component; a carrier; a flavouring. The active component may include one or more of nicotine; caffeine; a cannabidiol oil; a non-pharmaceutical formulation, e.g. a formulation which is not for treatment of a disease or physiological malfunction of the human body. The active component may be carried by the carrier, which may be a liquid, including propylene glycol and/or glycerine. The term “flavouring” may refer to a component that provides a taste and/or a smell to the user. The flavouring may include one or more of: Ethylvanillin (vanilla); menthol, Isoamyl acetate (banana oil); or other. The precursor may include a substrate, e.g. reconstituted tobacco to carry one or more of the active component; a carrier; a flavouring.

As used herein, a "storage portion" may be a portion of the apparatus adapted to store the precursor. It may be implemented as fluid-holding reservoir or carrier for solid material depending on the implementation of the precursor as defined above.

As used herein, a "flow path" may refer to a path or enclosed passageway through an aerosol generating apparatus, e.g. for delivery of an aerosol to a user. The flow path may be arranged to receive aerosol from an aerosol generating unit. When referring to the flow path, upstream and downstream may be defined in respect of a direction of flow in the flow path, e.g. with an outlet being downstream of an inlet.

As used herein, a "delivery system" may be a system operative to deliver an aerosol to a user. The delivery system may include a mouthpiece and a flow path.

As used herein, a "flow" may refer to a flow in a flow path. A flow may include aerosol generated from the precursor. The flow may include air, which may be induced into the flow path via a puff by a user.

As used herein, a “puff” (or "inhale" or “draw”) by a user may refer to expansion of lungs and/or oral cavity of a user to create a pressure reduction that induces flow through the flow path.

As used herein, an "aerosol generating unit" may refer to a device configured to generate an aerosol from a precursor. The aerosol generating unit may include a unit to generate a vapour directly from the precursor (e.g. a heating system or other system) or an aerosol directly from the precursor (e.g. an atomiser including an ultrasonic system, a flow expansion system operative to carry droplets of the precursor in the flow without using electrical energy or other system). A plurality of aerosol generating units to generate a plurality of aerosols (for example, from a plurality of different aerosol precursors) may be present in an aerosol generating apparatus.

As used herein, a “heating system” may refer to an arrangement of at least one heating element, which is operable to aerosolise a precursor once heated. The at least one heating element may be electrically resistive to produce heat from the flow of electrical current therethrough. The at least one heating element may be arranged as a susceptor to produce heat when penetrated by an alternating magnetic field. The heating system may be configured to heat a precursor to below 300 or 350 degrees C, including without combustion.

As used herein, a "consumable" may refer to a unit that includes a precursor. The consumable may include an aerosol generating unit, e.g. it may be arranged as a cartomizer. The consumable may include a mouthpiece. The consumable may include an information carrying medium. With liquid or gel implementations of the precursor, e.g. an e-liquid, the consumable may be referred to as a “capsule” or a “pod” or an “e-liquid consumable”. The capsule/pod may include a storage portion, e.g. a reservoir or tank, for storage of the precursor. With solid material implementations of the precursor, e.g. tobacco or reconstituted tobacco formulation, the consumable may be referred to as a “stick” or “package” or “heat- not-burn consumable”. In a heat-not-burn consumable, the mouthpiece may be implemented as a filter and the consumable may be arranged to carry the precursor. The consumable may be implemented as a dosage or pre-portioned amount of material, including a loose-leaf product.

As used herein, an "information carrying medium" may include one or more arrangements for storage of information on any suitable medium. Examples include: a computer readable medium; a Radio Frequency Identification (RFID) transponder; codes encoding information, such as optical (e.g. a bar code or QR code) or mechanically read codes (e.g. a configuration of the absence or presents of cutouts to encode a bit, through which pins or a reader may be inserted).

As used herein “heat-not-burn” (or “HNB” or “heated precursor”) may refer to the heating of a precursor, typically tobacco, without combustion, or without substantial combustion (i.e. localised combustion may be experienced of limited portions of the precursor, including of less than 5% of the total volume).

As used herein, "electrical circuitry" may refer to one or more electrical components, examples of which may include: an Application Specific Integrated Circuit (ASIC); electronic/electrical componentry (which may include combinations of transistors, resistors, capacitors, inductors etc); one or more processors; a non-transitory memory (e.g. implemented by one or more memory devices), that may store one or more software or firmware programs; a combinational logic circuit; interconnection of the aforesaid. The electrical circuitry may be located entirely at the apparatus, or distributed between the apparatus and/or on one or more external devices in communication with the apparatus, e.g. as part of a system. As used herein, a "processing resource" (or "processor " or “controller”) may refer to one or more units for processing data, examples of which may include an ASIC, microcontroller, FPGA, microprocessor, digital signal processor (DSP) capability, state machine or other suitable component. A processing resource may be configured to execute a computer program, e.g. which may take the form of machine readable instructions, which may be stored on a non-transitory memory and/or programmable logic. The processing resource may have various arrangements corresponding to those discussed for the circuitry, e.g. on-board and/or off board the apparatus as part of the system. As used herein, any machine executable instructions, or computer readable media, may be configured to cause a disclosed method to be carried out, e.g. by a aerosol generating apparatus or system as disclosed herein, and may therefore be used synonymously with the term method.

As used herein, an “external device” (or “peripheral device”) may include one or more electronic components external to an aerosol generating apparatus. Those components may be arranged at the same location as the aerosol generating apparatus or remote from the apparatus. An external device may comprise electronic computer devices including: a smartphone; a PDA; a video game controller; a tablet; a laptop; or other like device.

As used herein, a "computer readable medium/media" (or “memory” or "data storage") may include any medium capable of storing a computer program, and may take the form of any conventional non- transitory memory, for example one or more of: random access memory (RAM); a CD; a hard drive; a solid state drive; a memory card; a DVD. The memory may have various arrangements corresponding to those discussed for the circuitry /processor. The present disclosure includes a computer readable medium configured to cause an apparatus or system disclosed herein to perform a method as disclosed herein.

As used herein, a "communication resource" (or "communication interface") may refer to hardware and/or firmware for electronic information/data transfer. The communication resource may be configured for wired communication (“wired communication resources”) or wireless communication (“wireless communication resource”). Wireless communication resources may include hardware to transmit and receive signals by radio and may include various protocol implementations e.g. the 802.11 standard described in the Institute of Electronics Engineers (IEEE) and Bluetooth™ from the Bluetooth Special Interest Group of Kirkland Wash. Wired communication resources may include; Universal Serial Bus (USB); High-Definition Multimedia Interface (HDMI) or other protocol implementations. The apparatus may include communication resources for wired or wireless communication with an external device.

As used herein, a "network" (or "computer network") may refer to a system for electronic information/data transfer between a plurality of apparatuses/devices. The network may, for example, include one or more networks of any type, which may include: a Public Land Mobile Network (PLMN); a telephone network (e.g. a Public Switched Telephone Network (PSTN) and/or a wireless network); a local area network (LAN); a metropolitan area network (MAN); a wide area network (WAN); an Internet Protocol Multimedia Subsystem (IMS) network; a private network; the Internet; an intranet.

It will be appreciated that any of the disclosed methods (or corresponding apparatuses, programs, data carriers, etc.) may be carried out by either a host or client, depending on the specific implementation (i.e. the disclosed methods/apparatuses are a form of communication(s), and as such, may be carried out from either ‘point of view’, i.e. in corresponding to each other fashion). Furthermore, it will be understood that the terms “receiving” and “transmitting” encompass “inputting” and “outputting” and are not limited to an RF context of transmitting and receiving electromagnetic (e.g. radio) waves. Therefore, for example, a chip or other device or component for realizing embodiments could generate data for output to another chip, device or component, or have as an input data from another chip, device, or component, and such an output or input could be referred to as “transmit” and “receive” including gerund forms, that is, “transmitting” and “receiving,” as well as such “transmitting” and “receiving” within an RF context.

Referring to Fig. 1 , an example aerosol generating apparatus 1 includes a power supply 2, for supply of electrical energy. The apparatus 1 includes an aerosol generating unit 4 that is driven by the power supply 2. The power supply 2 may include an electric power supply in the form of a battery and/or an electrical connection to an external power source. The apparatus 1 includes a precursor s, which in use is aerosolised by the aerosol generating unit 4 to generate an aerosol. The apparatus 2 includes a delivery system 8 for delivery of the aerosol to a user.

Electrical circuitry (not shown in figure 1) may be implemented to control the interoperability of the power supply 4 and aerosol generating unit 6.

Fig. 2 shows an implementation of the apparatus 1 of Fig. 1 , where the aerosol generating apparatus 1 is configured to generate aerosol from a liquid precursor.

In this example, the apparatus 1 includes a device body 10 and a consumable 30.

In this example, the body 10 includes the power supply 4. The body may additionally include any one or more of electrical circuitry 12, a memory 14, a wireless interface 16, one or more other components 18.

The electrical circuitry 12 may include a processing resource for controlling one or more operations of the body 10 and consumable 30, e.g. based on instructions stored in the memory 14.

The wireless interface 16 may be configured to communicate wirelessly with an external (e.g. mobile) device, e.g. via Bluetooth.

The other component(s) 18 may include one or more user interface devices configured to convey information to a user and/or a charging port, for example (see e.g. Fig. 3). The consumable 30 includes a storage portion implemented here as a tank 32 which stores the liquid precursor s (e.g. e-liquid). The consumable 30 also includes a heating system 34, one or more air inlets 36, and a mouthpiece 38. The consumable 30 may include one or more other components 40.

The body 10 and consumable 30 may each include a respective electrical interface (not shown) to provide an electrical connection between one or more components of the body 10 with one or more components of the consumable 30. In this way, electrical power can be supplied to components (e.g. the heating system 34) of the consumable 30, without the consumable 30 needing to have its own power supply.

In use, a user may activate the aerosol generating apparatus 1 when inhaling through the mouthpiece 38, i.e. when performing a puff. The puff, performed by the user, may initiate a flow through a flow path in the consumable 30 which extends from the air inlet(s) 34 to the mouthpiece 38 via a region in proximity to the heating system 34.

Activation of the aerosol generating apparatus 1 may be initiated, for example, by an airflow sensor in the body 10 which detects airflow in the aerosol generating apparatus 1 (e.g. caused by a user inhaling through the mouthpiece), or by actuation of an actuator included in the body 10. Upon activation, the electrical circuitry 12 (e.g. under control of the processing resource) may supply electrical energy from the power supply 2 to the heating system 34 which may cause the heating system 32 to heat liquid precursor s drawn from the tank to produce an aerosol which is carried by the flow out of the mouthpiece 38.

In some examples, the heating system 34 may include a heating filament and a wick, wherein a first portion of the wick extends into the tank 32 in order to draw liquid precursor 6 out from the tank 32, wherein the heating filament coils around a second portion of the wick located outside the tank 32. The heating filament may be configured to heat up liquid precursor 6 drawn out of the tank 32 by the wick to produce the aerosol.

In this example, the aerosol generating unit 4 is provided by the above-described heating system 34 and the delivery system 8 is provided by the above-described flow path and mouthpiece 38.

In variant embodiments (not shown), any one or more of the precursor s, heating system 34, air inlet(s) 36 and mouthpiece 38, may be included in the body 10. For example, the mouthpiece 36 may be included in the body 10 with the precursors and heating system 32 arranged as a separable cartomizer.

Figs. 3a and 3b show an example implementation of the aerosol generating device 1 of Fig. 2. In this example, the consumable 30 is implemented as a capsule/pod, which is shown in Fig. 3a as being physically coupled to the body 10, and is shown in Fig. 3b as being decoupled from the body 10.

In this example, the body 10 and the consumable 30 are configured to be physically coupled together by pushing the consumable 30 into an aperture in a top end 11 the body 10, with the consumable 30 being retained in the aperture via an interference fit. In other examples (not shown), the body 10 and the consumable 30 could be physically coupled together in other ways, e.g. by screwing one onto the other, through a bayonet fitting, or through a snap engagement mechanism, for example.

The body 10 also includes a charging port (not shown) at a bottom end 13 of the body 10.

The body 10 also includes a user interface device configured to convey information to a user. Here, the user interface device is implemented as a light 15, which may e.g. be configured to illuminate when the apparatus 1 is activated. Other user interface devices are possible, e.g. to convey information haptically or audibly to a user.

In this example, the consumable 30 has an opaque cap 31 , a translucent tank 32 and a translucent window 33. When the consumable 30 is physically coupled to the body 10 as shown in Fig. 3a, only the cap 31 and window 33 can be seen, with the tank 32 being obscured from view by the body 10. The body 10 includes a slot 15 to accommodate the window 33. The window 33 is configured to allow the amount of liquid precursor 6 in the tank 32 to be visually assessed, even when the consumable 30 is physically coupled to the body 10.

Fig. 4 shows an implementation of the apparatus 1 of Fig. 1 , where the aerosol generating apparatus 1 is configured to generate aerosol by a heat not-burn process.

In this example, the apparatus 1 includes a device body 50 and a consumable 70.

In this example, the body 50 includes the power supply 4 and a heating system 52. The heating system 54 includes at least one heating element 54. The body may additionally include any one or more of electrical circuitry 56, a memory 58, a wireless interface 60, one or more other components 62.

The electrical circuitry 56 may include a processing resource for controlling one or more operations of the body 50, e.g. based on instructions stored in the memory 58.

The wireless interface 60 may be configured to communicate wirelessly with an external (e.g. mobile) device, e.g. via Bluetooth.

The other component(s) 62 may include an actuator, one or more user interface devices configured to convey information to a user and/or a charging port, for example (see e.g. Fig. 5).

The body 50 is configured to engage with the consumable 70 such that the at least one heating element 54 of the heating system 52 penetrates into the solid precursor 6 of the consumable. In use, a user may activate the aerosol generating apparatus 1 to cause the heating system 52 of the body 50 to cause the at least one heating element 54 to heat the solid precursor 6 of the consumable (without combusting it) by conductive heat transfer, to generate an aerosol which is inhaled by the user.

Fig. 5 shows an example implementation of the aerosol generating device 1 of Fig. 2. As depicted in Fig. 5, the consumable 70 is implemented as a stick, which is engaged with the body 50 by inserting the stick into an aperture at a top end 53 of the body 50, which causes the at least one heating element 54 of the heating system 52 to penetrate into the solid precursor 6.

The consumable 70 includes the solid precursor 6 proximal to the body 50, and a filter distal to the body 50. The filter serves as the mouthpiece of the consumable 70 and thus the apparatus 1 as a whole. The solid precursor 6 may be a reconstituted tobacco formulation.

In this example, the at least one heating element 54 is a rod-shaped element with a circular transverse profile. Other heating element shapes are possible, e.g. the at least one heating element may be bladeshaped (with a rectangular transverse profile) or tube-shaped (e.g. with a hollow transverse profile).

In this example, the body 50 includes a cap 51. In use the cap 51 is engaged at a top end 53 of the body 50. Although not apparent from Fig. 5, the cap 51 is moveable relative to the body 50. In particular, the cap 51 is slidable and can slide along a longitudinal axis of the body 50.

The body 50 also includes an actuator 55 on an outer surface of the body 50. In this example, the actuator 55 has the form of a button.

The body 50 also includes a user interface device configured to convey information to a user. Here, the user interface device is implemented as a plurality of lights 57, which may e.g. be configured to illuminate when the apparatus 1 is activated and/or to indicate a charging state of the power supply 4. Other user interface devices are possible, e.g. to convey information haptically or audibly to a user.

The body may also include an airflow sensor which detects airflow in the aerosol generating apparatus 1 (e.g. caused by a user inhaling through the consumable 70). This may be used to count puffs, for example.

In this example, the consumable 70 includes a flow path which transmits aerosol generated by the at least one heating element 54 to the mouthpiece of the consumable.

In this example, the aerosol generating unit 4 is provided by the above-described heating system 52 and the delivery system 8 is provided by the above-described flow path and mouthpiece of the consumable 70.

Fig. 6 shows an example system 80 for managing an aerosol generating apparatus 1 , such as those described above with reference to any of Figs. 1-5.

The system 80 as shown in Fig. 1 includes a mobile device 82, an application server 84, an optional charging station 86, as well as the aerosol generating apparatus 1 .

In this example, aerosol generating apparatus 1 is configured to communicate wirelessly, e.g. via Bluetooth™, with an application (or “app”) installed on the mobile device 2, via a wireless interface included in the aerosol generating apparatus 1 and via a wireless interface included in the mobile device 82. The mobile device 82 may be a mobile phone, for example. The application on the mobile phone is configured to communicate with the application server 84, via a network 88. The application server 84 may utilise cloud storage, for example.

The network 88 may include a cellular network and/or the internet.

In other examples, the aerosol generating apparatus 1 may be configured to communicate with the application server 84 via a connection that does not involve the mobile device 82, e.g. via a narrowband internet of things (“NB-loT”) or satellite connection. In some examples, the mobile device 82 may be omitted from the system 80.

A skilled person would readily appreciate that the mobile device 82 may be configured to communicate via the network 88 according to various communication channels, preferably a wireless communication channel such as via a cellular network (e.g. according to a standard protocol, such as 3G or 4G) or via a WiFi network.

The app installed on the mobile device 82 and the application server 84 may be configured to assist a user with managing their aerosol generating apparatus 1 , based on information communicated between the aerosol generating apparatus 1 and the app, information communicated directly between the aerosol generating apparatus 1 and the application server 84, and/or information communicated between the app and the application server 84.

The charging station 86 (if present) may be configured to charge (and optionally communicate with) the aerosol generating apparatus 1 , via a charging port on the aerosol generating apparatus 1 . The charging port on the smoking substitute device 10 may be a USB port, for example, which may allow the aerosol generating apparatus 1 to be charged by any USB-compatible device capable of delivering power to the aerosol generating apparatus 1 via a suitable USB cable (in this case the USB-compatible device would be acting as the charging station 86). Alternatively, the charging station could be a docking station specifically configured to dock with the aerosol generating apparatus 1 and charge the aerosol generating apparatus 1 via the charging port on the aerosol generating apparatus 1 .

As discussed with reference to Figs. 1 to 6, the present disclosure provides an aerosol generating device that comprises a heater and a power source configured to supply power to the heater. The heater may correspond to the heating element 54 described with reference to Figs. 1 to 6. The power source may correspond to the power supply 2 described with reference to Figs. 1 to 6.

The aerosol generating device further comprises a memory comprising firmware. The firmware is configured to control the application of power to the heater in a heater mode, wherein the heater mode has a temperature profile with a target temperature.

According to some embodiments of the present invention, the firmware includes a control loop 100 to regulate the temperature of the heater to the target temperature. Fig. 7 is a flowchart showing an example of the control loop 100. In aerosol generating devices which implement the control loop 100 example shown in Fig. 7, the power source is a battery, and the heater is a resistive heater.

In the example shown in Fig. 7, the control loop 100 operates in a repeating cycle with a repetition period of 20ms. However, in alternative embodiments, the repetition period may be different.

The control loop 100 includes a step 102 of receiving a target resistance of the heater. The target resistance is saved in a memory of the aerosol generating device and corresponds to the target temperature of the heater.

The control loop 100 further includes a step 104 of receiving a measurement of the resistance of the heater. The measurement of the resistance of the heater is a measurement of the voltage output by the battery divided by a measurement of the current through the heater.

The target resistance of the heater and the measurement of the resistance of the heater are taken as inputs into a PID controller 106 of the control loop. The PID controller 106 is a proportional-integral- derivative controller, which calculates and outputs 108 an average power to be applied to the heater from the power source to regulate the resistance of the heater to the target resistance of the heater, and to thereby regulate the temperature of the heater to the target temperature of the heater.

When the average power to be applied to the heater is calculated to be greater than the maximum power output of the battery, the PID controller 106 outputs the maximum power of the battery as the average power. When the average power to be applied to the heater is calculated to be less than zero, the PID controller 106 outputs zero as the average power.

In the example shown in Fig. 7, the control loop 100 next includes a step 110 of calculating a heater-on fraction (or a “duty cycle”). The heater-on fraction is calculated from a power ratio which is the average power divided by the power output of the power source (where power output by the power source is equal to the voltage output by the power source squared divided by the measured resistance of the heater). The heater on fraction is equal to a number ratio which is an integer number of sub-periods during which the heater is on divided by the total number of sub-periods in the repetition period where the integer number of sub-periods is calculated such that the number ratio is as close to the power ratio as possible. The control loop 100 next includes a step 112 of outputting, in accordance with the calculated heater-on fraction, an on signal which causes power to be applied to the heater from the power source, and an off signal which causes substantially zero power to be applied to the heater from the power source. The on-signal is output at the start of the repetition period, and the off signal is output after the heater-on fraction of the repetition period. In this way, power is applied to the heater from the power source for the heater-on fraction of the repetition period only.

The heater on fraction is equal to the number ratio, which may not be exactly equal to the power ratio, because the on-signal and the off-signal can each only be output after an integer number of sub-periods of the overall repetition period. The length of each of the sub-periods is 400 microseconds (which may be different in alternative embodiments). As an example, if the power ratio is 20%, for the first 10 400 microsecond time slots in the 20 millisecond repetition period, the heater will be switched on, and for the following 40 400 microsecond time slots in the 20 millisecond repetition period, the heater will be switched off. In this case, the heater-on fraction is identical to the power ratio. In other embodiments, the repetition period may be between 1 and 50 milliseconds. The length of each time slot may be consequently longer or shorter than 400 microseconds, dependent on the length of the repetition period.

As another example, if the power ratio is 25.5%, for the first 13 400 microsecond time slots in the 20 millisecond repetition period, the heater will be switched on, and for the following 37 400 microsecond time slots in the 20 millisecond repetition period, the heater will be switched off. In other words, the heater on fraction in this case is 26%, approximating the power ratio as closely as possible given the number of sub-periods within the repetition period.

In alternative embodiments, the control loop does not include the steps of calculating the heater-on fraction and outputting the on-signal and the off-signal. Instead, for example, the aerosol generating device comprises a variable power supply, and the average power is applied to the heater by varying the output of a variable power supply.

In some embodiments, the control loop comprises more steps than those in Fig. 7. Fig. 8 is a flowchart showing an example of a control loop which comprises more steps than those shown in Fig. 7.

Steps of the control loop 200 which are described with reference to Fig. 7 are labelled with the same reference numerals for clarity.

In the example shown in Fig. 8, the control loop has a step 216 of receiving a cap (“extractor”) position signal indicative of a measured position of the cap relative to the body of the device. If the cap position signal indicates that the position of the cap is in a position in which the heater is exposed, the control loop outputs a cap warning signal and subsequently the control loop stops running 220. The cap warning signal generates an alert 128 presented to a user of the device.

The control loop 200 has a further step 222 of receiving a power source temperature signal indicative of a measured temperature of the power source. If the power source temperature signal indicates that the temperature of the power source is over 50°C, the control loop outputs a high temperature warning signal and subsequently the control loop stops running 220. Similarly, if the power source temperature signal indicates that the temperature of the power source is below -10°C, the control loop outputs a low temperature warning signal, and subsequently the control loop stops running 220. The high temperature and the low temperature warning signals generate an alert 224 presented to a user of the device.

The control loop has a further step 226 of receiving a power source voltage signal indicative of a measured voltage output by the power source. If the power source voltage signal indicates that the voltage output by the power source is below 3V, the control loop outputs a voltage warning signal, and subsequently the control loop stops running 220. The voltage warning signal causes a low voltage protection operation 228 to be run. The control loop has a further step 230 of receiving a power source current signal indicative of a measured current output by the power source. If the power source current signal indicates that the current output by the power source is over 5A, the control loop outputs a high current warning signal, and subsequently the PID control loop stops running. Similarly, if the power source current signal indicates that the current output by the power source is below 0.1 A, the control loop outputs a low current warning signal, and subsequently the control loop stops running. The high current warning signal causes a short circuit protection 232 operation to be carried out, and the low current warning signal causes an open circuit protection 234 operation to be carried out.

Fig. 8 further shows that the control loop further comprises a step 236 of checking whether the control loop has been running for over 315 seconds, and when the control loop has been running for over 315 seconds, the control loop stops running 238.

In some embodiments, the firmware further comprises initialisation instructions 340 which are configured to be run before the control loop 100, 200. Fig. 9 is a flowchart showing an example of the initialisation instructions 340.

In the example shown in Fig. 9, the initialisation instructions 340 begin to run upon receiving a signal from an input device, which may be the actuator 55 described with reference to Figs. 1 to 6.

The initialisation instructions include a step 342 of outputting a stop-charging signal to stop the charging of the power source.

The initialisation instructions then include a step 344 of initialising parameters of the control loop, including the heating time which is initialised to 0.

Subsequently, the initialisation instructions include a step 346 of receiving a power source voltage signal indicative of a measured voltage output by the power source. If the power source voltage signal indicates that the voltage output by the power source is below 3.45V, the initialisation instructions output a voltage warning signal, and the initialisation instructions subsequently stop running 348. The voltage warning signal causes a low voltage protection operation to be run 350.

Lastly, the initialisation instructions include a step 352 of applying a voltage of 3.3V to an op-amp of the aerosol generative device. The op-amp may be used to amplify a voltage across a resistor in series with the heater to measure the resistance of the heater.

In alternative embodiments, the steps of the initialisation instructions may be carried out in a different order. Further, the initialisation instructions may comprise additional steps to those shown in the example of Fig. 9, and/or may not comprise all of the steps shown in Fig. 9.

Fig. 10 is a flowchart 460 including an example of the initialisation instructions 340 and an example of the control loop 200 together. The initialisation instructions 340 are those described with reference to Fig. 9. The control loop 200 is that described with reference to Fig. 8. The individual steps of the initialisation instructions 340 and of the control loop 200 are not labelled in Fig. 10. See Fig.8 and Fig. 9 respectively for the labelling of the individual steps of the control loop 200 and the initialisation instructions 340.

According to some embodiments of the present invention, the temperature profile 500 includes a preheat phase 502, an overshoot phase 504 and a primary heating phase 506. An example of a temperature profile 500 is shown in Fig. 11 A. Fig.11 B shows how the temperature of the heater varies, as the heater is heated in accordance with the temperature profile shown in Fig. 11 A.

As shown in Fig, 1 1A, in the pre-heat phase 502 and in the overshoot phase 504, the target temperature of the heater is the overshoot temperature 510. In the primary heating phase, the target temperature is the primary heating temperature 506.

As shown in Fig, 11 B, in the pre-heat phase 502 the temperature of the heater increases from an initial temperature 508 to an overshoot temperature 510.

As further shown in Fig. 11 B, in the overshoot phase 504, the temperature of the heater is maintained at the overshoot temperature 510.

As further shown in Fig. 11 B, in the primary heating phase 506, the temperature of the heater decreases from the overshoot temperature to the primary temperature 512.

The height, h, of the overshoot peak, which is the difference between the primary temperature 512 and the overshoot temperature 510 is approximately between 10°C and 30°C.

The duration of the rise and fall of the overshoot peak, which are respectively the duration over which the temperature increases between the primary temperature 512 and the overshoot temperature 510, and the duration over which the temperature decreases from the overshoot temperature 510 to the primary temperature 512 are approximately 5 to 8 seconds and depend upon the power rating of the power source, the resistance of the heater and the ambient temperature.

In different embodiments, the duration of the overshoot phase 504 varies. In some embodiments, the duration of the overshoot phase 504 is between 10 seconds and 30 seconds. In other embodiments, the duration of the overshoot phase 504 is between 1 second and 3 seconds. In other embodiments, the duration of the overshoot phase 504 is approximately 0 seconds.

In some embodiments, the width, w, of the overshoot peak, which is the total duration of the duration of the overshoot phase 504 combined with the duration over which the temperature increases between the primary temperature 512 and the overshoot temperature 510, and the duration over which the temperature decreases from the overshoot temperature 510 to the primary temperature 512, is approximately 30 to 40 seconds.

In the embodiment shown in Figs.11 A and 11 B, the primary heating phase 506 occurs straight after the overshoot phase 504, such that at the start of the primary heating phase 506 the temperature of the heater decreases from the overshoot temperature 510 to the primary temperature 512. 1 In other embodiments, such as that shown in Figs. 12A and 12B, the temperature profile 600 further includes an overshoot decay phase 614 in which the temperature of the heater decreases from the overshoot temperature 510 to the primary temperature 512.

As shown in Fig. 12A, the overshoot decay phase 614 comprises a plurality of stepped decay phases of equal duration. During each stepped decay phase, the target temperature is a respective one of a plurality of consecutively decreasing step temperatures.

In different embodiments, the number of stepped decay phases may vary from approximately 5 to approximately 200. In different embodiments, the duration of each of the stepped decay phases may vary from approximately 0.1 seconds to approximately 10 seconds.

In embodiments of the invention described with reference to Figs. 1 1A , 11 B, 12A and 12B the temperatures of each phase of the temperature profile 500 may be regulated to the target temperatures using the control loop 100, 200 as described with reference to Figs. 7 to 9, or the temperatures may be regulated to the target temperatures using another temperature regulation method.

In the primary heating phase 506, the aerosol generating device is suitable for use by the user such that the user can readily inhale aerosol generated by the aerosol generating device. In the pre-heat phase 502 and the overshoot phase 504, the aerosol generating device may not generate sufficient aerosol for the user to readily inhale aerosol generated by the aerosol generating device.

In some embodiments, the firmware of the aerosol generating device further comprises preheating indicator instructions.

In some embodiments, the preheating indicator instructions are configured to receive a heating phase signal indicative of whether the heater is being heated in the pre-heat phase 502, the overshoot phase 504, the overshoot decay phase 614, or the primary heating phase 506. When the heating phase signal indicates that the heater is being heated in the pre-heat phase 502 or the overshoot phase 504, the preheating indicator instructions may generate an alert presented to the user of the device, such that the user knows that they may not be able to readily inhale aerosol from the aerosol generating device.

In other embodiments, the preheating indicator instructions are configured to receive a heating phase signal indicative of a phase changing from the overshoot phase 504, or the overshoot decay phase 614, to the primary heating phase 506. When the phase signal indicates that phase has changed from the overshoot phase 504, or the overshoot decay phase 614, to the primary heating phase 506, the preheating indicator instructions generate an alert presented to the user of the device, such that the user knows that they can readily inhale aerosol from the aerosol generating device.

When the target temperatures are controlled by a control loop 100, 200 as described with reference to Figs. 7 to 10, the preheating indicator instructions may be within the control loop 100, 200.

According to some embodiments of the present invention, the firmware may be configured to control the application of power to the heater in a lower heater mode and in a higher heater mode, wherein the lower heater mode has a lower mode temperature profile with a lower mode target temperature and the higher heater mode has a higher mode temperature profile with a higher mode target temperature.

The higher mode target temperature is higher than the lower mode target temperature.

Each of the lower heater mode and the higher heater mode is selectable by a user of the aerosol generating device. For example, the lower heater mode may be selectable by a first interaction with an input device (which may be the actuator 55 described with reference to Figs. 1 to 6) and the higher heater mode may be selectable by a second interaction with an input device.

The respective target temperatures in the lower mode temperature profile and the higher mode temperature profile may be regulated by the control loop 100, 200 described with reference to Figs. 7 to 10.

Further, the lower mode temperature profile and the higher mode temperature profile may each comprise a pre-heat phase 502, an overshoot phase 504 and a primary heating phase 506 as described with reference to Figs. 1 1A and 11 B.

In this case, the higher mode primary heating temperature is higherthan the lower mode primary heating temperature, such that each heating mode provides a different user experience. The higher mode primary heating temperature is approximately 345°C, and the lower mode primary temperature is approximately 315°C.

Further, the height, h, of the overshoot peak and the duration of the overshoot phase 504 in each of the higher mode temperature profile and the lower mode temperature profile is the same to simplify the implementation of the two heating modes.

In alternative embodiments, the height, h, of the overshoot peak and/or the duration of the overshoot phase 504 may depend on the primary heating temperature 506. For example, the height, h, of the overshoot peak may be the same proportion of the magnitude of the primary heating temperature 512 for the lower mode temperature profile and the higher mode temperature profile.

The lower mode temperature profile and the higher mode temperature profile may each further comprise the overshoot decay phase as described with reference to Figs. 12A and 12B.

In this case, to simplify the implementation of the two heating modes, the duration of each higher mode stepped decay phase is the same as the duration of each lower mode stepped decay phase, and the number of higher mode stepped decay phases are the same as the number of each lower mode stepped decay phase.

In alternative embodiments, the duration of each stepped decay phase and/or the number of stepped decay phases may depend upon the heating mode. For example, there may be a larger number of stepped decay phases for a greater difference between the overshoot temperature and the primary temperature.

Claims

1 . An aerosol generating device comprising: a heater; a power source configured to supply power to the heater; and, a memory comprising firmware, the firmware configured to control the application of power to the heater in a lower heater mode and a higher heater mode, wherein the lower heater mode has a lower mode temperature profile with a lower mode target temperature and the higher heater mode has a higher mode temperature profile with a higher mode target temperature, and wherein the firmware includes a control loop comprising a PID controller, the PID controller configured to: receive a temperature signal indicative of a measurement of the temperature of the heater, calculate, using the temperature signal, a PID controller output; and, output the PID controller output; wherein the control loop is configured to control, based on the PID controller output, a power applied to the heater from the power source to thereby regulate the temperature of the heater to a respective one of the lower mode or higher mode target temperatures.

2. The aerosol generating device of claim 1 wherein the control loop is configured to operate in a repeating cycle with a repetition period, wherein optionally the repetition period is between 1 millisecond and 50 milliseconds.

3. The aerosol generating device of claim 2 wherein the PID controller output is an average power to be applied to the heater during the repetition period to thereby regulate the temperature of the heater to a respective one of the lower mode or higher mode target temperatures,

4. The aerosol generating device of claim 3 wherein the control by the control loop of the power applied to the heater from the power source further includes: calculating a heater-on fraction, the heater-on fraction being the average power divided by a power output of the power source; and, outputting a power control signal, such that power is applied to the heater from the power source for the heater-on fraction of the repetition period only,

5. The aerosol generating device of any of the preceding claims wherein the temperature signal includes a measurement of the resistance of the heater.

6. The aerosol generating device of any of the preceding claims wherein the lower mode temperature profile includes a lower mode pre-heat phase, a lower mode overshoot phase and a lower mode primary heating phase, wherein in the lower mode pre-heat phase, the lower mode target temperature is a lower mode overshoot temperature, such that during the lower mode pre-heat phase the temperature of the heater increases from an initial temperature to the lower mode overshoot temperature wherein in the lower mode overshoot phase, the lower mode target temperature is the lower mode overshoot temperature, such that during the lower mode overshoot phase the temperature of the heater is regulated to the lower mode overshoot temperature; and wherein in the lower mode primary heating phase, the lower mode target temperature is a lower mode primary temperature, such that during the lower mode primary heating phase the temperature of the heater is regulated to the lower mode primary temperature, wherein the lower mode overshoot temperature is greater than the lower mode primary temperature.

7. The aerosol generating device of any of the preceding claims wherein the higher mode temperature profile includes a higher mode pre-heat phase, a higher mode overshoot phase and a higher mode primary heating phase, wherein in higher mode the pre-heat phase, the higher mode target temperature is a higher mode overshoot temperature, such that during the higher mode pre-heat phase the temperature of the heater increases from an initial temperature to the higher mode overshoot temperature wherein in the higher mode overshoot phase, the higher mode target temperature is a higher mode overshoot temperature, such that during the higher mode primary phase the temperature of the heater is regulated to the higher mode overshoot temperature; and wherein in the higher mode primary heating phase, the higher mode target temperature is a higher primary temperature, such that during the higher mode primary heating phase the temperature of the heater is regulated to the higher primary temperature, wherein the higher mode overshoot temperature is greater than the higher mode primary temperature.

8. The aerosol generating device of claim 6 the duration of the lower mode overshoot phase is between 10 second and 30 seconds.

9. The aerosol generating device of claim 7 wherein the duration of the higher mode overshoot phase is between 10 seconds and 30 seconds.

10. The aerosol generating device of any of claims 6 to 9 wherein the duration of the lower mode overshoot phase and the duration of the higher mode overshoot phase are the same.

11. The aerosol generating device of claim 6 wherein the difference between the lower mode primary temperature and the lower mode overshoot temperature is between 5°C and 40°C.

12. The aerosol generating device of claim 7 wherein the difference between the higher mode primary temperature and the higher mode overshoot temperature is between 5°C and 40°C.

13. The aerosol generating device of any of claims 6 to 12 wherein the difference between the higher mode primary temperature and the higher mode overshoot temperature and the difference between the lower mode primary temperature and the lower mode overshoot temperature are the same.

14. The aerosol generating device of any of claims 6 to 13 wherein the lower mode temperature profile further includes lower mode overshoot decay phase comprising a plurality of lower mode stepped decay phases, wherein in each lower mode stepped decay phase, the lower mode target temperature is a respective one of a plurality of lower mode step temperatures, such that during each lower mode stepped decay phase the temperature of the heater decreases, and such that in the lower mode overshoot decay phase the temperature of the heater decreases from the lower mode overshoot temperature to the lower mode primary temperature.

15. The aerosol generating device of any of claims 7 to 14 wherein the higher mode temperature profile further includes higher mode overshoot decay phase comprising a plurality of higher mode stepped decay phases, wherein in each higher mode stepped decay phase, the higher mode target temperature is a respective one of a plurality of higher mode step temperatures, such that during each higher mode stepped decay phase the temperature of the heater decreases, and such that in the higher mode overshoot decay phase the temperature of the heater decreases from the higher mode overshoot temperature to the higher mode primary temperature.