FIELD OF INVENTION

The present invention relates to an aerosol-generating inhaler having a sensor for monitoring the stress level of a user during use.

BACKGROUND

Inhalers such as electronic cigarettes or vaping devices are becoming increasingly popular. They are used to deliver a flavor or a stimulant to a user in the form of aerosol without combustion. Users of such inhalers may wish to control the amount of flavor or stimulant released based on their preferences or other factors.

The vaping devices available in the market are often standardized and may not cater to the needs of an individual.

Therefore, there exists a need for a device that can adapt to its user and control the delivery of aerosol in a safe and reliable manner.

SUMMARY OF THE INVENTION

According to an aspect of the invention, there is provided an aerosol-generating inhaler comprising a housing having an air flow path defined between an air inlet and an air outlet of the housing, wherein the air outlet allows generated aerosol to exit; a galvanometer disposed on the body of the inhaler, wherein the galvanometer is configured to measure galvanic skin response to determine a stress level of a user of the inhaler; and a controller configured to control the release of the aerosol based on the determined stress level. Advantageously, the inhaler of the invention can determine a stress level of a user while vaping and based on that control the amount of aerosol delivered to the user for inhalation. As the galvanometer is integrated in the inhaler itself, the user is not required to make any extra effort or couple any additional device with the inhaler. Moreover, as the substance contained in the aerosol is regulated according to the user’s current level of stress, it is possible to maintain the user’s stress at a baseline or optimal level while vaping.

Preferably, the galvanometer is integrated in an activation switch of the inhaler such that the user’s skin comes in contact with the galvanometer when the user interacts with the activation switch to activate the inhaler.

Advantageously, the user is not required to perform any additional step for stress level determination as the galvanometer gets activated when the user turns on the inhaler using the activation button. Preferably, the galvanometer is disposed at a side surface of the inhaler such that the user’s skin comes in contact with the galvanometer when the user holds the inhaler during use.

Advantageously, stress level monitoring can be done constantly while the user is using the inhaler. Preferably, the inhaler further comprises an accelerometer to detect movements of the user when using the inhaler.

Advantageously, it is possible to detect if the user is performing any physical activity that might impact stress level readings.

Preferably, the controller is configured to ignore the galvanic skin response measured by the galvanometer based on the movements detected by the accelerometer.

Advantageously, stress level can be determined more accurately by ignoring a stress reading made during a time when it can be erroneous such as when a physical activity is being performed by the user while using the inhaler, as determined by the accelerometer.

Preferably, the controller is configured to determine a baseline galvanic skin response for the user using the measurements made by the galvanometer over different periods of time.

Advantageously, it is possible to determine the user’s optimal or normal stress level during vaping by recording the stress level data over a period of time. Preferably, the baseline galvanic skin response comprises a range with an upper baseline limit and a lower baseline limit. The baseline galvanic skin response may also comprise a safety threshold, and the controller may be configured to take an action if the safety threshold is exceeded. Advantageously, having a baseline range with upper and lower threshold values provides greater flexibility and allows more realistic adjustments to be made to the inhaler for the benefit of the user.

Preferably, the controller is configured to increase or decrease the amount of substance in the aerosol released when the measured galvanic skin response is respectively lower or higher than the baseline galvanic skin response. The controller may also be configured to increase or decrease the amount of substance in the aerosol released based on time of day or data related to user vaping operations, including duration of vaping puffs or frequency of vaping puffs.

Advantageously, the stress level of the user can be brought to the optimal level by controlling the amount of aerosol based on the measured stress level.

Preferably, the controller is configured to determine a number of puffs inhaled by the user per unit of time.

Advantageously, it is also possible to determine the user’s stress level based on the frequency of puffs inhaled during vaping or the duration of puffs. According to another aspect of the invention, there is provided a method of operating an aerosol-generating inhaler comprising activating the inhaler to release aerosol from the inhaler; measuring galvanic skin response to determine a stress level of a user using a galvanometer disposed on the body of the inhaler; and controlling the release of the aerosol based on the determined stress level.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 A shows an inhaler with a stress sensor according to one aspect of the invention; Fig. 1 B shows an inhaler with a stress sensor according to another aspect of the invention;

Fig. 2 is a block diagram of various components in the inhaler of Figs 1 A and 1 B;

Figs. 3A-3B are flow diagrams for the operation of the inhaler of Figs. 1 A and 1 B; Fig. 4 is a graph showing a pattern of stress level of a user during a typical week; and

Fig. 5 is a graph showing a comparison of measured galvanic skin response of the user at different time periods with baseline limits.

DETAILED DESCRIPTION Next, various aspects of the invention will be described. Note that the same or similar portions are denoted with the same or similar reference signs in the descriptions of the drawings below. Note that the drawings are schematic and a ratio of each size is different from a real one. Therefore, specific sizes and the like should be judged in consideration of the following descriptions. Needless to say, portions of which relationship and ratios of mutual sizes are different between the mutual drawings are included.

Fig. 1A shows a non-combustion-type flavor inhaler 100, which is an instrument for inhaling a flavor without combustion. The inhaler 100 has a rod-like shape with a main body 101 extending from a non-mouthpiece end 102 to a mouthpiece end 103. An air channel or path is defined in the main body 100 between the opposite ends 102, 103. The inhaler 100 in the present example is an electronic cigarette or a vaping device. The inhaler 100 works by vaporizing or heating an aerosol source contained inside the inhaler 100 to release a flavor or a stimulant for a user to inhale through the mouthpiece end 103. The construction and operation of such an inhaler is well-known in the art and will be understood by a skilled person. The inhaler 100 also includes an activation switch 104 that may be configured to perform at least one of a turn-on and a turn-off of a power source of the inhaler 100. The activation switch 104 may be a push button or a touch button disposed at any convenient location on the surface of the main body 101 of the inhaler 101. People nowadays like to monitor their activity level, body stats, sleep quality, etc. for various reasons. There are several devices or gadgets available in the market that could do that. However, such devices are either wearable devices which may be considered as too intrusive by some users or other non-wearable devices that may not be convenient to use or carry around.

Monitoring the stress level may be of particular interest as stress impacts various other body functions. For example, when a person is experiencing a high level of stress, his or her heart rate, blood pressure, brain activity is likely to increase which may have negative health impact. However, somewhat increased level of stress may be preferred in certain situations such as during an exam, a demanding task or an emergency. There are several activities that may increase the stress level, such as strenuous physical activity, a substance intake, or an emotional setback. Keeping stress level at check and controlling an external stimulus accordingly may help in maintaining a good general state of wellbeing. For the users of e-cigarettes or similar devices, it may also be desirable to control the intake of aerosol based on their current stress level.

According to one aspect of the invention, a stress sensor 204 is integrated in the switch 104 such that when the user touches or presses the switch 104 to turn on the inhaler 100, the sensor 204 measures the stress level of the user by skin contact as described in detail later.

Fig. 1 B shows an inhaler 200 similar to the inhaler 100 shown in Fig. 1A, with only one difference. That is, in the inhaler 200, the stress sensor 204 is not disposed on the activation switch 104 but on a side surface 105 of the main body. The sensor 204 may be provided in the form of a strip or a tag and be placed at a location such that when the user holds the inhaler 200 during use, his or her skin comes in contact with the sensor 204 allowing it to determine the user’s stress level.

It is to be understood that the inhaler 100, 200 may be of any suitable shape and size and could have different functioning mechanisms. Also, the activation switch 104 may be disposed at either side or bottom of the inhaler. Preferably, the sensor 204 is disposed such that it comes in contact with the user’s skin during normal use, without requiring the user to specifically locate the sensor and make contact with it. Fig. 2 shows various components of the inhaler 100, 200. The inhaler 100, 200 comprises an aerosol source 201 and a vaporizer 202 that vaporizes the aerosol source 201 to release aerosol containing the flavor and/or stimulant for the user to inhale. In the present example, the aerosol source 201 is a substance containing nicotine. The aerosol source 201 may be in the form of solid or liquid and is heated by the vaporizer (including a heat source) to release the aerosol without combustion. The vaporizer can include a heating coil to vaporize liquid or include a heating chamber to heat a solid aerosol source (e.g., a tobacco stick) without combustion, or any other appropriate configuration applicable for an aerosol generating device. The vaporizer 202 may be powered by a power source 203. The power source 203 is, for example, a lithium ion battery. The power source 203 supplies an electric power necessary for an action of the inhaler 100, 200. For example, the power source 203 supplies the electric power to all other components or modules included in the inhaler 100, 200.

The aerosol source 201 may include an additional flavor source (not shown) provided on the side of the mouthpiece end 103 beyond a holder holding the aerosol source 201 , and generates a flavor to be inhaled by the user together with the aerosol generated from the aerosol source 201. Examples of the flavor source that can be used include shredded tobacco, a formed body including a tobacco raw material formed granular, a formed body including the tobacco raw material formed to have a sheet in shape. The flavor source may include a plant, such as mint or a herb. A flavor, such as menthol, may be added to the flavor source.

The inhaler 100, 200 further includes a stress sensor. Preferably, the stress sensor is a galvanometer 204 which measures the electrodermal activity of the user. Specifically, the galvanometer 204 determine the stress level of the user by measuring the galvanic skin response (GSR) or skin conductance resulting from the change in sweat gland activity reflective of the user’s emotional state. As the skin conductance is typically captured from the hand and foot regions, electrodes present in the galvanometer 204 make contact with the user’s hand when the user uses the inhaler.

The inhaler 100, 200 also includes a controller 206 that is configured to control various modules or components in the inhaler. The controller 206 also processes the data captured by the galvanometer 204 as explained above. The inhaler 100, 200 may further include an accelerometer 205. The accelerometer 205 is configured to measure the movements of the user when using the inhaler. The galvanic skin response of the user may increase due to intense physical movements such as during exercising or walking fast. In such cases, the galvanometer 204 may determine the user as having a high stress level, although it is not necessarily in response to emotional stress. To minimize such distortions in stress determination caused by intense movements, it is preferred that the user is at rest to get accurate readings. Therefore, measurements made by the galvanometer 204 during any intense movements can be ignored by the controller 206. However, such movement data may be recorded for other purposes, such as for heart-rate determination or for general user reference.

The inhaler 100, 200 may also include a puff detector 207. In one example, the puff detector 207 is connected to a pressure sensor (not shown) that detects air pressure caused by the inhaling action of the user. The puff detector 207 detects a puff state based on a detection result of the sensor (for example, negative pressure in the inhaler 100, 200). Accordingly, the puff detector 207 can determine the number of times of puff actions of inhaling the aerosol. The puff detector 207 can also detect a time period required for one puff action of inhaling the aerosol.

The inhaler 100, 200 may also include a memory 208, a light-emitting element 209, and other modules 210 such as a display and a sound emitter. The light-emitting element 209 such as an LED may be disposed at the tip of the non-mouthpiece end 102. Such an LED may exhibit a first light-emitting mode in a puff state where the aerosol has been being inhaled and a second light-emitting mode different from the first light-emitting mode, in a non-puff state where the aerosol has not been inhaled. Here, the light-emitting mode is defined by a combination of parameters, such as the amount of light of the light-emitting element, the number of light-emitting elements in a lighting state, a color of the light- emitting element, and a cycle in which lighting of the light-emitting element and non lighting of the light-emitting element repeat. The different light-emitting mode means that at least any one of the above parameters is different.

Fig. 3A shows a flow diagram 300A of operation of the inhaler 100, 200. At step 301 , an aerosol-generating device is activated. In the present example, the aerosol source 201 may be heated up or vaporized to release the aerosol when the user presses the activation switch 104 on the inhaler 100. A predetermined operation of the switch 104, such as continuously pressing over the predetermined number of times, turns the power source 203 of the inhaler 100, 200 on. When the operation of the switch 104 turns the power source 203 on, the power source 203 supplies the electric power to the vaporizer 202, galvanometer 204, controller 206 and other components in the inhaler 100, 200.

At step 302, a baseline GSR or stress range of the user is determined. In the present example, the controller 206 calculates a baseline GSR for the user based on the readings obtained from the galvanometer 204 over time. i.e. by continual learning process. A baseline galvanic skin response may be used as an indicator of user’s optimal stress level. As the user’s stress level may vary throughout the day depending on a number of factors, it is preferred to define a baseline GSR range with an upper GSR limit and a lower GSR limit. The baseline range includes all GSR values within an upper value and a lower value for a given period. This allows monitoring the stress level with greater flexibility. Moreover, each user has different ‘normal’ skin conductance, it may not be possible to set a fixed value as baseline. The baseline range for the user may be modified over time as more user data is available. It is to be understood that the baseline range may be stored in the memory 208 of the device and simply fetched by the controller 206 in step 302.

An upper safety limit is also provided, which is generally higher than the upper GSR limit. GSR measurements that are above the upper safety limit are considered to be indicative of abnormal stress levels that are potentially harmful, or could become harmful. The upper safety limit or threshold may be predetermined for all users. Alternatively the upper safety limit may be calculated based on user specific factors such as age, weight and gender.

At step 303, the galvanic skin response of a user is measured. In the present example, the galvanometer 204 activates the electrodes to measure the galvanic skin response of the user when the user presses the activation switch 104 in the inhaler 100 and/or holds the inhaler 200 from the side. As described before, a stress level of the user is determined based on the galvanic skin response. In the present example, the galvanometer 204 sends the measured galvanic skin response readings to the controller 206 to determine the stress level of the user. Preferably, the controller 206 may take an average of multiple readings received and determines a stress level of the user based on an algorithm and user’s recorded historical data.

At step 304, it is determined whether the measured GSR is within the baseline range. In the present example, the controller 206 determines whether the measured GSR obtained in step 303 is included in the baseline GSR range determined or retrieved in step 302. In comparing, the controller 206 determines if the measured GSR falls outside the upper or the lower baseline limits. If it does not, then the controller 206 proceeds to step 305 or else proceeds to step 306. In the present example, if the measured GSR is not within the baseline range, the measured GSR should be either above the upper baseline limit or below the lower baseline limit.

At step 305, an amount of substance in the aerosol is maintained. In the present example, when the measured GSR is within the baseline range, the controller 206 may conclude that the user’s stress level is within the optimal range and therefore continues the delivery of the aerosol unchanged from the source 201. By doing so, the same amount of substance (such as nicotine) as before is continued to be inhaled by the user.

At step 320, it is determined whether the measured GSR is above the upper safety limit. As mentioned, GSR levels that are above the upper safety limit are considered to be abnormal. In the present example, upon determining that the measured GSR is above the upper safety limit, the controller 206 performs a safety action at step 321. The safety action may include reducing an amount of substance in the aerosol, or suspending operation of the inhaler 100, 200. Additionally, or alternatively the safety action of the controller 206 may include generating a visible alert using the light emitting element 209 or sounding an audible alarm. These may be interpreted by the user as warning messages so that they can take counter measures to reduce their stress levels so that they drop back below the upper safety limit.

At step 306, it is determined whether the measured GSR is above the upper baseline limit. In the present example, upon determining that the measured GSR falls outside the baseline range, but is nevertheless below the upper safety limit, the controller 206 further determines if the measured GSR exceeds the upper baseline limit, which is a threshold value for increased GSR. When the user’s GSR is higher than the upper baseline limit, it may indicate that the user is under higher than normal stress, although within safe levels (i.e. below the upper safety limit), and the controller 206 thus proceeds to step 308. On the other hand, when the measured GSR is not exceeding the upper baseline limit, the controller 206 concludes that the measured GSR value is below the lower baseline limit since the result of falling outside baseline rage from step 304 only provides two options of either above upper baseline limit or below the lower baseline limit. In this case, the controller 206 proceeds to step 307.

At step 307, the controller 206 is configured to control an amount of substance in the aerosol based on user preference or other data. In the present example, when the measured GSR is outside the baseline range but not exceeding the upper baseline limit, the controller 206 concludes that the measured GSR value is less than the lower baseline limit, indicative of very low stress levels. When nicotine is used as the substance, it is well-known that certain quantity of nicotine is useful in alleviating stress and calming the user. On the other hand, an increased amount of nicotine may also impart mental alertness and aid in concentration. While lower GSR value may indicate the user is calm and at rest, it may as well indicate that the user is feeling lethargic and struggling to cope with work. In one scenario the controller 206 can control the amount of substance in the aerosol in order to maintain a relaxed physiology and a low stress level. This may be achieved by maintaining the amount of substance in the aerosol or by reducing the amount of substance, depending on user preference. In one example, the controller 206 can maintain or reduce the amount of substance based on the time of day, such as after 8pm. For example, in the evening the user may prefer to maintain a relaxed physiology so that they can have an uninterrupted sleep. The controller 206 can also maintain or reduce the amount of substance in the aerosol based on other data such as the frequency of vaping. It has been found that the frequency of vaping, or the duration of vaping puffs, can be indicative of the relaxation state of the user, and less frequency vapes can indicate that the user wishes to maintain a relaxed state. Therefore, the controller can maintain or reduce the amount of substance in the aerosol at step 307 if the frequency of vaping, or the duration of vaping puffs, is below a predetermined threshold. In another scenario, at step 307, the controller 206 can increase the amount of substance in the aerosol. This can be done in order to increase the GSR value so that it falls once more within the baseline range. This may be particularly desirable during working hours when the user may wish to maintain a normal stress level. In this scenario, at step 307, the controller 206 can increase the amount of substance in the aerosol to provide a boost and make the user more active and alert. This may be done in a number of ways. In one example, the amount of aerosol released from the source 201 may be increased, thereby increasing the quantity of substance to be inhaled by the user. In another example, a multi-tank vaping device may be used which includes two or more liquid reservoirs each containing a liquid with different concentration of substance. By switching supply to the reservoir containing a higher concentration liquid, it is possible to increase the substance intake while maintaining the same aerosol amount. In yet another example, substance delivery can be increased by controlling the heating operation (e.g., by controlling the energy supplied to a heater) in heat-not-burn and vapor-based devices, or controlling a pressurized liquid source in vapor-based devices. The controller 206 can increase the amount of substance in the aerosol based on user preferences or based on other data such as time of day or frequency of vaping. In particular, the controller 206 may, at step 307, increase the amount of substance in the aerosol if the time of day coincides with the user’s normal working pattern. This may be preset as 9am to 5pm, Monday to Friday, but this may be adjusted based on user preferences or other data which are indicative of a different working pattern. The controller 206 may also, at step 307, obtain data regarding the frequency of vaping, or the duration of vaping puffs, and may increase the amount of substance in the aerosol when the frequency of vaping is above a predetermined threshold. It has been found that users vape more frequently, or with longer puffs, when they wish to maintain a normal state of alertness and this may be detected by the controller 206 to achieve the desired state of alertness based on GSR measurements.

At step 308, an amount of substance in the aerosol is increased. In the present example, if the user’s GSR exceeds the upper baseline limit it may indicate that the user is agitated or in high state of stress. A certain quantity of nicotine may be useful in alleviating stress and calming the user and it is also observed that cigarette smokers tend to smoke more under high stress. As such, when determining that the user’s GSR is above upper baseline limit but still in a safe range (i.e., below safety limit), the controller 206 will increase the amount of substance in the aerosol to calm down the user. Fig. 3B shows a flow diagram 300B of additional optional steps in the process of Fig. 3A. It is to be understood that the steps in 300B are although preferable but not essential for the functioning of the invention.

Continuing from step 304, the controller 206 determines whether the measured GSR is within the baseline range as described above. If it is determined that the measured GSR is within the baseline range, the controller 206 proceeds to step 309 else proceeds to step 310.

At step 309, it is determined if longer or more frequent puffs are detected. In the present example, the puff detector 207 senses each time the user takes in a puff of aerosol through the inhaler 100. The puff detector 207 continuously monitors the frequency and duration of puffs taken by the user and feeds in this puff data to the controller 206. The controller 206 preferably compares the puff frequency and duration with the user’s historic puff data which may be stored in the memory 208. If the controller 206 determines that the puffs are getting more frequent and/or longer than usual, it proceeds to step 311 else it proceeds to step 312.

At step 311 , an amount of substance in the aerosol is increased. In the present example, upon determining that the puffs are more frequent and/or longer, the controller 206 may conclude that the user desires higher substance intake and therefore it increases the amount of substance in the aerosol delivered to the user. In this way, the user preference is taken care of without requiring any user intervention. Moreover, by continually monitoring the user’s vaping pattern, a baseline for puff frequency and length can be determined. Deviations from the baseline could also help in determining the emotional state. For example, longer and more frequent puffs may indicate a more stressed state.

At step 312, an amount of substance in the aerosol is maintained. In the present example, if the controller 206 determines that the frequency and duration of puffs is normal as interpreted from the historic puff data, the controller 206 takes no further action and continues delivering the aerosol with the same amount of substance as before.

Going back to step 304, if the measured GSR is found to be outside the baseline range, then at step 310, it is determined whether any intense user movements are detected. In the present example, the accelerometer 205 detects any intense movements by the user while vaping, e.g. brisk walking. It is known that such movements may increase the GSR of the user but not necessarily indicative of the stress level. The accelerometer 205 preferably feeds in such movement data to the controller 206. The controller proceeds to step 313 if such data is received from the accelerometer 205 else proceeds to step 320.

At step 313, the measured GSR is ignored. In the present example, upon determining the user movements, the controller 206 concludes that the measured GSR is outside the baseline range due to such movements. Therefore, the controller 206 ignores the measured GSR for that period as it is unlikely to be indicative of the user’s actual stress level. In this way, any error caused due to the user movements is avoided. Next, the controller 206 proceeds to step 309 checking the puff data as explained above.

Fig. 4 shows a graph 400 of a varying stress level of a user during a typical week. With days of the week plotted on the X-axis and stress level plotted on the Y-axis, a stress pattern of the user may be drawn. In the present example, the stress pattern of the user resembles a sinusoidal waveform of varying amplitude. A flat line overlaying the stress pattern represents a default stress baseline, which is not optimized for a particular user at a given time period. However, for any given day, the stress level of the user may vary throughout the day starting with low stress in the morning, peaking during the day, and going down again in the night. Throughout the week, the stress level may vary from day to day. Typically, stress may be higher during the week days and lower during the weekends. In the shown example, Wednesday is the most stressful day, e.g. due to high workload, and Saturday the least stressful day, e.g. due to leisure time at home.

It is to be understood that the graph 400 only shows one possible example of the stress pattern of the user considering a typical week. Another user with a different lifestyle may have a quite different pattern. For example, a user working over the weekends or in night shifts may have high stress level during the weekends and nights. Also, the stress pattern would differ when the user is away from work, e.g. on holidays or during social events. The controller 206 therefore constantly monitors the user’s stress pattern over different periods of time and keeps learning to update the baseline range. It is also to be understood that the graph 400 is to illustrate the change of stress over time and the baseline range is simplified as a curve for simplicity without showing the upper limit and lower limit. Fig. 5 shows a graph 500 of the user’s GSR data at different time periods. In the graph 500, X-axis has time periods at which the stress level is measured and Y-axis has GSR or skin conductance values in microsiemens (pS). The galvanometer 204 measures the galvanic skin response of the user and the controller 206 records it at each time period. As explained above, the controller 206 also determines the baseline range for the user with the upper and lower baseline limits. The controller 206 also determines an upper safety limit, which is either specific to the user or is predetermined by default. As shown, in the first period, the user’s GSR is determined to be at 3 pS, which is within a range between the upper baseline limit of 4 and the lower baseline limit of 2. However, in the second period, the measured GSR is 12 pS which is higher than the upper baseline limit of 10. As explained above, when the controller 206 determines that the measured GSR is outside the baseline range, it regulates the amount of substance in the aerosol. The controller 206 thus ensures that the user’s stress level stays at the optimum level for the time of the day or according to the user preference. In this example, the measured GSR is at all times below the upper safety limit.

Using the invention described above, it is possible to monitor the stress level of the user without employing any additional device or requiring the user to perform any additional step. Moreover, by controlling the delivery of aerosol based on the determined stress level it is possible to keep the user’s stress level at the baseline or optimal level at most times. This allows the user to enjoy vaping without having to consciously monitor the intake of aerosol.

In the above-described invention, stress readings may be presented to the user though a small display on the inhaler. In addition, it may be possible to alert the user of high or low stress level by flashing a different-colored LED or by emitting an alert sound. In addition or alternatively, it is possible to connect the inhaler to a user’s personal device such as a mobile phone or smartphone which may run an application (such as iOS/Android App) to display current stress level, movement data, puff data, amount of aerosol intake, etc. in a user-friendly format to the user of the inhaler. Such device when connected to the inhaler may also be configured to receive various measurements from the inhaler and determine the baseline as described above. The foregoing description of illustrative embodiments has been presented for purposes of illustration and of description. It is not intended to be exhaustive or limiting with respect to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the disclosed embodiments.