Aerosol generating device and control method

Abstract

This aerosol producing device includes a heating unit, a power source, a suction sensing unit, and a control unit for controlling power supply from the power source to the heating unit in accordance with a control sequence. The control sequence includes at least a first section having a first temperature as a control target value, a second section having a second temperature lower than the first temperature as the control target value, and a third section having a third temperature higher than the second temperature as the control target value. When, in the second section, a suction sensing count does not satisfy a condition, the control unit transitions the temperature control to the third section at a first point in time and performs control so that the temperature of the heating unit reaches the third temperature at a second point in time and, if the suction sensing count does satisfy the condition, transitions the temperature control to the third section at a third point in time and performs control so that the temperature of the heating unit reaches the third temperature at a fourth point in time earlier than the second point in time.

Description

[Technical field]

[0001] The present disclosure relates to an aerosol generating device and a control method. [Background technology]

[0002] Electrically heated aerosol generating devices are known that generate aerosol by heating an aerosol source and deliver the generated aerosol to a user. For example, an electronic cigarette is one such aerosol generating device, and generates an aerosol containing a flavor component and is inhaled by the user.

[0003] The amount of aerosol generated from an aerosol source per unit time varies depending on the nature and shape of the substrate containing the aerosol source as well as the temperature at which the substrate is heated. Therefore, the aerosol generating device controls the heating temperature so that the amount of aerosol delivered to the user is a desired amount. In general, a representation of the change in temperature over time is called a temperature profile, and a time-series definition of the temperature control specifications for achieving a desired temperature profile is called a heating profile.

[0004] For example, Patent Document 1 discloses a temperature profile in which the temperature of the heating element is increased to a high value in a first stage, the temperature of the heating element is decreased to a lower value in a second stage, and the temperature of the heating element is gradually increased in a third stage. This temperature profile flattens the amount of aerosol generated over time to some extent. Patent Document 1 also discloses that, in relation to this temperature profile, the timing of transition of temperature control from one stage to the next stage is determined using indicators such as elapsed time, the temperature of the heating element, the amount of power supplied to the heating element, or the number of suctions. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-74797 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, no matter what index is used, there is a limit to how much the quality of the user's inhalation experience can be improved by simply shifting the timing of the temperature control. For example, if the temperature control is shifted early as a result of the user's fast inhalation, the content of the temperature control appropriate for the stage after the shift should be different from that of the normal shift.

[0007] In view of the above-mentioned circumstances, the technology disclosed herein aims to realize improved temperature control for aerosol generation. [Means for solving the problem]

[0008] According to a first aspect, the present invention provides a heating unit that generates an aerosol by heating an aerosol source, a power source that supplies power to the heating unit, and a detection unit that detects inhalation of the aerosol by a user. The power source has a first section for supplying power to the heating unit with a target value for temperature control of the heating unit set to a value corresponding to a first temperature, a second section after the first section for supplying power from the power source to the heating unit with a target value for temperature control of the heating unit set to a value corresponding to a second temperature lower than the first temperature, and a third section after the second section for supplying power from the power source to the heating unit with a target value for temperature control of the heating unit set to a value corresponding to a third temperature higher than the second temperature. and a control unit that performs control according to a control sequence that includes at least the following: wherein the control unit monitors a detection count representing the number of times that the inhalation is detected by the detection unit, at least in the second section, and if the detection count does not satisfy a predetermined condition, transitions the temperature control to the third section at a first point in time when a predetermined time has elapsed from a reference point in time, and performs the temperature control so that the temperature of the heating section reaches the third temperature at a second point in time after a certain length of time has elapsed; and if the detection count satisfies the predetermined condition, transitions the temperature control to the third section at a third point in time, and performs the temperature control so that the temperature of the heating section reaches the third temperature at a fourth point in time earlier than the second point in time.

[0009] The third point in time may be an earlier point in time than the first point in time.

[0010] The third point in time may be a point in time when the control unit determines that the number of detections satisfies the predetermined condition.

[0011] The third point in time may be a point in time when a time shorter than a remaining time until the first point in time has elapsed after the control unit determines that the number of detections satisfies the predetermined condition.

[0012] The third point in time may be equal to the first point in time.

[0013] The control unit may perform the temperature control so that when the temperature control is transitioned to the third zone as a result of the number of detections satisfying the specified condition, the temperature rise rate of the heating unit in the third zone is higher, compared to when the temperature control is transitioned to the third zone without the number of detections satisfying the specified condition.

[0014] The control unit may perform the temperature control so that when the temperature control is transitioned to the third zone as a result of the number of detections satisfying the specified condition, the temperature rise rate of the heating unit in the third zone is lower, compared to when the temperature control is transitioned to the third zone without the number of detections satisfying the specified condition.

[0015] The predetermined condition may include the number of detections reaching a threshold value.

[0016] The aerosol generating device may further include a receiving portion for receiving a tobacco article including the aerosol source, the tobacco article including an amount of the aerosol source that enables M inhalations of the aerosol (M is an integer greater than or equal to 2), and the threshold value may be greater than or equal to M / 2.

[0017] When the number of detections satisfies the specified condition, the control unit may select a rate of temperature rise of the heating unit in the third section depending on the frequency at which the suction is detected or the cumulative value of the time over which the suction is detected.

[0018] When the number of detections satisfies the specified condition, the control unit may determine the third point in time at which to transition the temperature control from the second zone to the third zone in accordance with the remaining time until the first point in time.

[0019] The control unit may count the number of detections from a point in time when the completion of pre-heating is notified to the user or a point in time when the second interval starts.

[0020] According to a second aspect, the present invention provides a heating unit that generates an aerosol by heating an aerosol source, a power source that supplies power to the heating unit, and a detection unit that detects inhalation of the aerosol by a user, and includes a first section in which a target value for temperature control of the heating unit is set to a value corresponding to a first temperature and power is supplied from the power source to the heating unit, a second section after the first section in which a target value for temperature control of the heating unit is set to a value corresponding to a second temperature lower than the first temperature and power is supplied from the power source to the heating unit, and a third section after the second section in which a target value for temperature control of the heating unit is set to a value corresponding to a third temperature higher than the second temperature and power is supplied from the power source to the heating unit. and a control unit that performs control according to a control sequence that includes at least the following: wherein the control unit monitors a detection frequency that indicates the frequency at which the inhalation is detected by the detection unit, at least in the second interval, and if the detection frequency does not satisfy a predetermined condition, transitions the temperature control to the third interval at a first point in time when a predetermined time has elapsed from a reference point, and performs the temperature control so that the temperature of the heating unit reaches the third temperature at a second point in time after a certain length of time has elapsed; and if the detection frequency satisfies the predetermined condition, transitions the temperature control to the third interval at the third point in time, and performs the temperature control so that the temperature of the heating unit reaches the third temperature at a fourth point in time earlier than the second point in time.

[0021] According to a third aspect, a heating unit that generates an aerosol by heating an aerosol source, a power source that supplies power to the heating unit, a detection unit that detects inhalation of the aerosol by a user, and a supply of power from the power source to the heating unit are at least divided into a first section in which a target value for temperature control of the heating unit is set to a value corresponding to a first temperature and power is supplied from the power source to the heating unit, a second section after the first section in which a target value for temperature control of the heating unit is set to a value corresponding to a second temperature lower than the first temperature and power is supplied from the power source to the heating unit, and a third section after the second section in which a target value for temperature control of the heating unit is set to a value corresponding to a third temperature higher than the second temperature and power is supplied from the power source to the heating unit. and a control unit that performs control according to a control sequence that also includes a control sequence that also includes a control unit that performs control according to ...

[0022] According to a fourth aspect, there is provided a control method for controlling the supply of power from a power source to a heating unit in an aerosol generating device according to a control sequence, the control method may include processing steps corresponding to any combination of the above-mentioned features of the aerosol generating device according to the first, second and third aspects. Effect of the Invention

[0023] The techniques disclosed herein provide improved temperature control for aerosol generation. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a perspective view showing the appearance of an aerosol generating device according to an embodiment. [Diagram 2] FIG. 2 is an explanatory diagram for explaining the insertion of a tobacco stick into the aerosol generation device of FIG. 1. [Diagram 3] FIG. 2 is a block diagram showing an example of a schematic circuit configuration of the aerosol generating device of FIG. [Figure 4] FIG. 4 is a block diagram showing an example of the configuration of a measurement circuit used for measuring a heating unit. [Diagram 5] FIG. 4 is an explanatory diagram for explaining a measurement period and a PWM control period during a heating period. [Figure 6] FIG. 4 is an explanatory diagram for explaining a temperature profile and a heating profile according to an embodiment. [Figure 7] FIG. 4 is an explanatory diagram showing an example of a temperature profile that can be realized in the first embodiment. [Figure 8] FIG. 11 is an explanatory diagram showing an example of a temperature profile that can be realized in the second embodiment. [Figure 9] FIG. 13 is an explanatory diagram showing an example of a temperature profile that can be realized in the third embodiment. [Figure 10] FIG. 13 is an explanatory diagram showing an example of a temperature profile that can be realized in the fourth embodiment. [Figure 11] FIG. 13 is an explanatory diagram showing an example of a temperature profile that can be realized in the fifth embodiment. [Figure 12] FIG. 23 is an explanatory diagram showing an example of a temperature profile that can be realized in the sixth embodiment. [Figure 13] FIG. 23 is an explanatory diagram showing an example of a temperature profile that can be realized in the seventh embodiment. [Figure 14] FIG. 23 is an explanatory diagram showing an example of a temperature profile that can be realized in the eighth embodiment. [Figure 15] 6 is a flowchart showing a first example of the flow of a temperature control process that can be executed in a temperature maintenance section after the temperature is lowered. [Figure 16] 10 is a flowchart showing a second example of the flow of a temperature control process that can be executed in a temperature maintenance section after the temperature is lowered. [Figure 17]10 is a flowchart showing an example of the flow of a temperature control process that can be executed in a re-heating section. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims, and not all combinations of features described in the embodiments are essential to the invention. Two or more features among the multiple features described in the embodiments may be arbitrarily combined. In addition, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0026] <<1. Device configuration example>> In this specification, the present disclosure will be described mainly as an example of application of the technology to a non-combustion device that generates an aerosol by heating an aerosol source to atomize it without combustion. Such a device may also be called a reduced risk product (RRP) or simply an electronic cigarette. However, the present disclosure is not limited to such an example, and the technology may be applied to any type of aerosol generating device, such as a combustion device or a medical nebulizer.

[0027] <1-1.Appearance> Fig. 1 is a perspective view showing the appearance of an aerosol generation device 10 according to one embodiment. Fig. 2 is an explanatory diagram for explaining the insertion of a tobacco stick into the aerosol generation device 10 shown in Fig. 1. Referring to Fig. 1, the aerosol generation device 10 includes a main body 101, a front panel 102, a display window 103, and a slider 104.

[0028] The main body 101 is a housing that supports one or more circuit boards of the aerosol generating device 10 therein. In this embodiment, the main body 101 has a rounded, approximately rectangular parallelepiped shape that is long in the vertical direction in the figure. The size of the main body 101 may be, for example, a size that a user can hold with one hand. The front panel 102 is a flexible panel member that covers the front surface of the main body 101. The front panel 102 may be detachable from the main body 101. The front panel 102 also functions as an input unit that accepts user input. For example, when a user presses the center of the front panel 102, a button (not shown) disposed between the main body 101 and the front panel 102 is pressed, and the user input can be detected. The display window 103 is a strip-shaped window that extends along the longitudinal direction at approximately the center of the front panel 102. Display window 103 transmits light emitted by one or more LEDs (Light-Emitting Diodes) disposed between main body 101 and front panel 102 to the outside.

[0029] The slider 104 is a cover member disposed on the upper surface of the main body 101 so as to be slidable along a direction 104a. As shown in FIG. 2, when the slider 104 is slid toward the viewer in the figure (i.e., the slider 104 is opened), an opening 106 on the upper surface of the main body 101 is exposed. When a user inhales aerosol using the aerosol generating device 10, the user inserts the tobacco stick 15 into a tubular insertion hole 107 along a direction 106a from the opening 106 exposed by opening the slider 104. That is, the insertion hole 107 serves as a receiving portion for receiving the tobacco stick 15. A cross section of the insertion hole 107 perpendicular to the axial direction may be, for example, a circle, an ellipse, or a polygon, and the cross-sectional area gradually decreases as it approaches the bottom surface. As a result, the outer surface of the tobacco stick 15 inserted into the insertion hole 107 is pressed by the inner surface of the insertion hole 107, preventing the tobacco stick 15 from falling out by frictional force and increasing the efficiency of heat transfer from the heating unit 130, which will be described later, to the tobacco stick 15. When the user has finished inhaling the aerosol, he or she pulls out the tobacco stick 15 from the insertion hole 107 and closes the slider 104.

[0030] The tobacco stick 15 is a tobacco article that holds a filler inside a cylindrical cigarette paper. The filler of the tobacco stick 15 may be, for example, a mixture of an aerosol-generating substrate and tobacco shreds. As the aerosol-generating substrate, a substrate containing any kind of aerosol source, such as glycerin, propylene glycol, triacetin, 1,3-butanediol, or a mixture thereof, may be used. The tobacco shreds are a so-called flavor source. The material of the tobacco shreds may be, for example, lamina or midrib. Note that a flavor source derived from a non-tobacco source may be used instead of the tobacco shreds.

[0031] The tobacco stick 15 includes an aerosol source (or an aerosol source and a flavor source) in an amount that allows M puffs of the aerosol. M may be any integer equal to or greater than 2. For example, M may be a value within a range of about 10 to 20, which is close to the number of puffs per cigarette in a typical cigarette.

[0032] In addition, the aerosol generating device 10 is not limited to the above example, and may be capable of receiving a tobacco article that is not in a stick shape (e.g., a tobacco capsule, a cartridge, or a reservoir). The aerosol source included in the tobacco article may be solid or liquid.

[0033] <1-2. Circuit configuration> Fig. 3 is a block diagram showing an example of a schematic circuit configuration of the aerosol generation device 10. Referring to Fig. 3, the aerosol generation device 10 includes a control unit 120, a storage unit 121, an input detection unit 122, a state detection unit 123, a suction detection unit 124, a light emission unit 125, a vibration unit 126, a communication interface (I / F) 127, a connection I / F 128, a heating unit 130, a first switch 131, a second switch 132, a battery 140, a boost circuit 141, a fuel gauge 142, a measurement circuit 150, and a thermistor 155.

[0034] The control unit 120 may be a processor such as a CPU (Central Processing Unit) or a microcontroller. The control unit 120 controls the overall functions of the aerosol generation device 10 by executing a computer program (also called software or firmware) stored in the storage unit 121. The storage unit 121 may be a semiconductor memory, for example. The storage unit 121 stores one or more computer programs and various data (for example, profile data describing a heating profile 50) used for heating control described later.

[0035] The input detection unit 122 is a detection circuit for detecting a user input. For example, the input detection unit 122 detects a user's pressing of the front panel 102 (i.e., pressing a button) and outputs an input signal indicating the detected state to the control unit 120. Note that the aerosol generation device 10 may include any type of input device, such as a button, a switch, or a touch-sensitive surface, instead of (or in addition to) the front panel 102. The state detection unit 123 is a detection circuit for detecting the open / closed state of the slider 104. The state detection unit 123 outputs a state detection signal indicating whether the slider 104 is open or closed to the control unit 120. The inhalation detection unit 124 is a detection circuit for detecting the inhalation (puff) of the tobacco stick 15 by the user. As an example, the inhalation detection unit 124 may include a thermistor (not shown) disposed near the opening 106. In this case, suction detection unit 124 can detect suction based on a change in the resistance value of the thermistor caused by a temperature change resulting from suction by the user. As another example, suction detection unit 124 may include a pressure sensor (not shown) disposed at the bottom of insertion hole 107. In this case, suction detection unit 124 can detect suction based on a decrease in air pressure caused by an airflow caused by suction. Suction detection unit 124 outputs, for example, a suction detection signal indicating whether suction is being performed to control unit 120.

[0036] The light emitting unit 125 includes one or more LEDs and a driver for driving the LEDs. The light emitting unit 125 causes each of the LEDs to emit light in accordance with an instruction signal input from the control unit 120. The vibration unit 126 includes a vibrator (e.g., an eccentric motor) and a driver for driving the vibrator. The vibration unit 126 causes the vibrator to vibrate in accordance with an instruction signal input from the control unit 120. The control unit 120 may use one or both of the light emitting unit 125 and the vibration unit 126 in an arbitrary pattern, for example, to notify the user of some status of the aerosol generating device 10 (e.g., the progress of a session). For example, the light emitting pattern of the light emitting unit 125 can be distinguished by factors such as the light emitting state (always emitting light / blinking / not emitting light), the blinking cycle, and the light emitting color of each LED. The vibration pattern of the vibration unit 126 can be distinguished by factors such as the vibration state (vibration / stop) and the vibration strength of the vibrator.

[0037] The wireless I / F 127 is a communication interface for wirelessly communicating the aerosol generation device 10 with other devices (e.g., a personal computer (PC) or a smartphone owned by a user). The wireless I / F 127 may be an interface conforming to any wireless communication protocol, such as Bluetooth (registered trademark), near field communication (NFC), or wireless local area network (LAN). The connection I / F 128 is a wired interface having a terminal for connecting the aerosol generation device 10 to other devices. The connection I / F 128 may be, for example, a universal serial bus (USB) interface. The connection I / F 128 may be used to charge the battery 140 from an external power source (via a power supply line not shown).

[0038] The heating unit 130 is a resistive heating component that generates an aerosol by heating the aerosol source contained in the aerosol generating substrate of the tobacco stick 15. For example, one or a mixture of two or more of copper, nickel alloy, chromium alloy, stainless steel, and platinum-rhodium may be used as the resistive heating material of the heating unit 130. One end of the heating unit 130 is connected to the positive electrode of the battery 140 via the first switch 131 and the boost circuit 141, and the other end of the heating unit 130 is connected to the negative electrode of the battery 140 via the second switch 132. The first switch 131 is a switching element provided in the power supply line between the heating unit 130 and the boost circuit 141. The second switch 132 is a switching element provided in the ground line between the heating unit 130 and the battery 140. The first switch 131 and the second switch 132 may be, for example, FETs (Field Effect Transistors).

[0039] The battery 140 is a power source for supplying power to the heating unit 130 and other components of the aerosol generation device 10. In FIG. 3, power supply lines from the battery 140 to components other than the heating unit 130 are omitted. The battery 140 may be, for example, a lithium-ion battery. The boost circuit (DC / DC converter) 141 is a voltage conversion circuit that amplifies the voltage of the battery 140 to supply power to the heating unit 130. The fuel gauge 142 is an IC chip for monitoring the remaining power of the battery 140 and other statuses. The fuel gauge 142 may periodically measure status values ​​of the battery 140, such as the state of charge (SOC), the degree of deterioration (SOH), the relative state of charge (RSOC), and the power supply voltage, and output the measurement results to the control unit 120.

[0040] When a user input requesting the start of heating is detected, the control unit 120 starts supplying power from the battery 140 to the heating unit 130. The user input here may be, for example, a long press of a button detected by the input detection unit 122. The control unit 120 outputs a control signal to the first switch 131 and the second switch 132 to turn on both switches, thereby supplying power from the battery 140 to the heating unit 130 with a voltage amplified by the boost circuit 141. When the first switch 131 and the second switch 132 are FETs, the control signal output from the control unit 120 to both switches is a control pulse applied to each gate. In temperature control described later, the control unit 120 adjusts the duty ratio of this control pulse by pulse width modulation (PWM). The control unit 120 may use pulse frequency modulation (PFM) instead of PWM.

[0041] <1-3. Heater temperature measurement> In this embodiment, the control unit 120 controls the supply of power from the battery 140 to the heating unit 130 so as to realize a desired temperature profile for providing a good user experience throughout the entire heating period including the preheating period and the inhalation period. The control may be mainly feedback control in which a temperature index having a correlation with the temperature of the heating unit 130 is a controlled variable and a duty ratio of PWM is a manipulated variable. Here, PID control is adopted as the feedback control. In this embodiment, the aerosol generating device 10 has two types of measuring units for measuring the temperature index of the heating unit 130. The measuring circuit 150 shown in FIG. 3 is one of the two types of measuring units, and the thermistor 155 is the other. The measuring circuit 150 is used to measure a first temperature index based on the electrical resistance value of the heating unit 130. The thermistor 155 is used to measure a second temperature index that depends on the temperature of the heating unit 130 during a period when a voltage cannot be applied to the heating unit 130 (an off period to be described later).

[0042] Fig. 4 is a block diagram showing an example of the configuration of the measurement circuit 150 shown in Fig. 3. Referring to Fig. 4, the measurement circuit 150 includes voltage dividing resistors 151, 152, and 153 and an operational amplifier 154. One end of the voltage dividing resistor 151 is connected to a power supply voltage V TEMP , and the other end is connected to one end of a voltage dividing resistor 152. The other end of the voltage dividing resistor 152 is grounded. A junction between the voltage dividing resistors 151 and 152 is connected to a terminal ADC_VTEMP of the control unit 120. An input to the terminal ADC_VTEMP indicates a reference value for measuring resistance values. One end of the voltage dividing resistor 153 is connected to a power supply voltage V TEMP and the other end is connected to the power supply line of the heating unit 130. A junction between the voltage dividing resistor 153 and the power supply line of the heating unit 130 is connected to a first input terminal of an operational amplifier 154. A second input terminal of the operational amplifier 154 is grounded. An output terminal of the operational amplifier 154 is connected to a terminal ADC_HEAT_TEMP of the control unit 120. An input to the terminal ADC_HEAT_TEMP indicates a value that changes depending on an electrical resistance value Rh that depends on the temperature of the heating unit 130. The control unit 120 can calculate the electrical resistance value Rh of the heating unit 130 based on the ratio of the input value to the terminal ADC_HEAT_TEMP to the input value (reference value) to the terminal ADC_VTEMP.

[0043] Here, the electric resistance value of the heating unit 130 has a characteristic that, for example, it increases monotonically as the temperature rises (i.e., it has a correlation with the temperature). Therefore, in this embodiment, the control unit 120 uses the electric resistance value of the heating unit 130 calculated by using the measurement circuit 150 as a temperature index (first temperature index) as a controlled variable of the PID control. For example, if the target temperature of the PID control at a certain point in time is H TGT [℃], the target temperature is calculated according to the following formula (1): TGT Can be converted to [Ω]:

number

[0044] In formula (1), H ENV is the reference environmental temperature, α is the temperature resistance coefficient of the resistive heating material of the heating unit 130, R ENVrepresents the electrical resistance at the reference ambient temperature. ENV , α and R ENV The values ​​of are all measured or derived in a preliminary evaluation test and are stored in the storage unit 121 in advance.

[0045] Of course, the control unit 120 may convert the electrical resistance value of the heating unit 130 into a temperature using a resistance temperature coefficient, and use the measured temperature thus derived as a control amount for PID control.

[0046] <1-4. Temperature control> As described above, in this embodiment, the temperature control of the heating unit 130 is performed by a method in which the duty ratio of the PWM of the power provided to the heating unit 130 is determined mainly by PID control. TGT [Ω] and the index value (measured resistance value) of the first temperature index in the current control cycle n (n is an integer) is R(n) [Ω]. The duty ratio D(n) of the control cycle n can be derived, for example, according to the following formula (2):

number

[0047] In equation (2), K p , K i and K d represent the proportional gain, integral gain, and differential gain, respectively. Note that in the second term on the right side, which is the integral term, saturation control may be applied to the accumulated value of the deviation of the index value from the target value. In this case, if the accumulated value exceeds a predetermined upper limit value, it is replaced with the upper limit value, and if the accumulated value falls below a predetermined lower limit value, it is replaced with the lower limit value.

[0048] In order to enable feedback control during the heating period, in this embodiment, the control unit 120 sets a part of the repeated control cycle as a measurement period for measuring the first temperature index, and sets the remaining control cycle as a PWM control period for performing PWM control. FIG. 5 is an explanatory diagram for explaining the measurement period and PWM control period during the heating period. The horizontal axis in the figure represents time, and the vertical axis represents the voltage applied to the heating unit 130. One control cycle during the heating period consists of an initial measurement period 20 and a remaining PWM control period 30. In the example of FIG. 5, the period from t0 to t1 is the measurement period 20 of one control cycle, and the period from t1 to t2 is the PWM control period 30 of the control cycle. Similarly, the period from t2 to t3 is the measurement period 20 of the next control cycle, and the period from t3 to t4 is the PWM control period 30 of the control cycle. The length of one control cycle corresponds to the period of measurement of the first temperature index, and may be, for example, several tens of milliseconds.

[0049] In the control cycle n, the control unit 120 applies a very short pulse 21 (e.g., a pulse width of 2 ms) to the heating unit 130 multiple times (e.g., 8 times) during the measurement period 20, and sets the average value of the resistance value calculated multiple times using the measurement circuit 150 within one measurement period 20 as the measurement value R(n) of the first temperature index. The control unit 120 uses the measurement value R(n) to calculate the PWM duty ratio D(n) of the control cycle n according to the above control formula. Then, in the PWM control period 30, the control unit 120 applies a pulse 31 having a pulse width W1 corresponding to the product of the length W0 of the period and the duty ratio D(n) to the heating unit 130 (outputting a control pulse having the same pulse width W1 to the first switch 131 and the second switch 132). Through the repetition of such feedback control, the temperature of the heating unit 130 is controlled to approach the target value.

[0050] The second temperature indicator based on the output value from thermistor 155 is used to determine the temperature of heating unit 130 during a period when no pulses are applied to heating unit 130, for example, for the purpose of efficiently lowering the temperature of heating unit 130, which has once been raised to a high value, to a lower value. Thermistor 155 is disposed near heating unit 130 and outputs a value that depends on the temperature of heating unit 130 to control unit 120.

[0051] <1-5. Temperature profile and heating profile> The control unit 120 executes temperature control of the heating unit 130 according to a heating profile, which is a control sequence that defines the temporal transition of control conditions for realizing a desired temperature profile. In this embodiment, the heating profile is made up of a plurality of sections that divide a heating period into time periods, and the temperature control specifications for each section are specified by target values ​​and other control parameters.

[0052] 6 is an explanatory diagram for explaining a temperature profile and a heating profile that can be adopted in this embodiment. In the diagram, the horizontal axis represents the elapsed time from the start of power supply to the heating unit 130, and the vertical axis represents the temperature of the heating unit 130. The thick broken line represents a temperature profile 40, as an example. The temperature profile 40 is made up of an initial preheating period (T0 to T2) and an inhalation possible period (T2 to T8) that follows the preheating period. As an example, the length of the entire inhalation possible period may be about 5 minutes.

[0053] The preheating period includes a temperature rise section (T0 to T1) in which the temperature of the heating unit 130 is rapidly raised from the environmental temperature H0 to the first temperature H1, and a temperature maintenance section (T1 to T2) in which the temperature of the heating unit 130 is maintained at the first temperature H1. In this way, by first rapidly heating the heating unit 130 to the first temperature H1, heat can be quickly and sufficiently distributed throughout the aerosol-generating substrate of the tobacco stick 15, making it possible to start providing good quality aerosol to the user sooner.

[0054] The inhalation period includes a maintenance section (T2-T3) in which the temperature of the heating unit 130 is maintained at the first temperature H1, a temperature drop section (T3-T4) in which the temperature of the heating unit 130 is lowered to the second temperature H2, and a maintenance section (T4-T5) in which the temperature of the heating unit 130 is maintained at the second temperature H2. In this way, by lowering the temperature of the heating unit 130, which has once risen to the first temperature H1, to the second temperature H2, it is possible to provide the user with a long and stable inhalation with a suitable smoking taste. The inhalation period further includes a temperature rise section (T5-T6) in which the temperature of the heating unit 130 is gradually raised from the second temperature H2 to the third temperature H3, a maintenance section (T6-T7) in which the temperature of the heating unit 130 is maintained at the third temperature H3, and a temperature drop section (T7-T8) in which the temperature of the heating unit 130 is lowered to the environmental temperature H0. In this way, by increasing the temperature of the heating section 130 again in the latter half of the inhalation period, it is possible to suppress deterioration of the smoking taste in a situation in which the aerosol source contained in the tobacco stick 15 is decreasing, and to provide the user with a highly satisfying experience until the end of the inhalation period.

[0055] As an example, the first temperature H1 may be 295° C., the second temperature H2 may be 230° C., and the third temperature H3 may be 260° C. However, different temperature profiles may be designed, for example, depending on the manufacturer's design guidelines, user preferences, or the characteristics of different types of tobacco articles.

[0056] Heating profile 50 is made up of eight sections S0-S7, with boundaries T1-T7. However, as will be explained later, the timing of the transition between two sections does not necessarily coincide with one of the illustrated times T1-T7, but rather depends on the end condition of each section. In the next section, a more specific configuration example of heating profile 50 will be explained for each section in turn.

[0057] <<2. Heating profile configuration example>> <2-1. Initial temperature rise (S0)> Section S0 is the first half of the preheating period. In section S0, PID control is performed by setting the target value of temperature control to a resistance value (hereinafter referred to as R1) corresponding to the first temperature H1. The proportional gain of the PID control in section S0 is set to a higher value compared to other sections, so that the time required for heating can be shortened as much as possible. Section S0 ends when the first temperature index reaches the resistance value R1.

[0058] <2-2. Maintaining temperature during preheating (S1)> Section S1 is the latter half of the preheating period. In section S1, PID control is performed with the target value of temperature control set to resistance value R1. The proportional gain of the PID control in section S1 can be set to a value that stabilizes the temperature of the heating unit 130 near the first temperature H1, unlike the case of the rapid temperature rise in section S0 (for example, it can be set to a value smaller than the proportional gain specified for section S0). Section S1 ends when a time length that can be set to a value within a range of several seconds has elapsed. At the end of section S1, the control unit 120 notifies the user of the end of the preheating period. The notification here may be performed by one or both of the light emission of the light emission unit 125 in a predetermined light emission pattern and the vibration of the vibration unit 126 in a predetermined vibration pattern. By sensing this notification, the user recognizes that preparation for suction is complete and that suction can be started.

[0059] <2-3. Start of session (S2)> Section S2 is the beginning section of the inhalation possible period. In section S2, PID control is performed with the target value of temperature control set to resistance value R1. The gain of the PID control in section S1 may be the same as that in section S1. Section S2 ends when a time length that may be set to a value within a range of several seconds to a dozen seconds has elapsed.

[0060] The user can start inhaling the aerosol generated by the aerosol generation device 10 from section S2. The control unit 120 measures statistics related to suction, such as the number of suction detections, the suction detection frequency, or the accumulated suction time, based on the suction detection signal input from the suction detection unit 124, and stores the measurement results in the storage unit 121. This measurement can be continued after section S3.

[0061] <2-4. Temperature fall (S3)> Section S3 is a section for lowering the temperature of the heating unit 130 that once rose to the first temperature H1 during the preheating period. In section S3, the control unit 120 stops the supply of power from the battery 140 to the heating unit 130 so that the temperature of the heating unit 130 drops toward the second temperature H2. In this specification, such a section in which power is not supplied to the heating unit 130 is referred to as an off section. The control unit 120 ends section S3, for example, when it is determined that the temperature of the heating unit 130 has reached the second temperature H2 based on a second temperature index based on an output value from the thermistor 155.

[0062] <2-5. Maintaining temperature after cooling (S4)> Section S4 is a section for maintaining the temperature of the heating unit 130 in the vicinity of the second temperature H2. In section S4, PID control is performed by setting the target value of the temperature control to a resistance value (hereinafter, R2) corresponding to the second temperature H2. The gain of the PID control in section S4 may be the same as that in sections S1 and S2. As described above, section S4 is a section in which the user can stably repeat inhalations with a suitable smoking taste, and continues for a longer time length (e.g., several tens of seconds to several minutes) compared with sections S2 and S3. If inhalations are performed at a fast pace in section S4, the aerosol source contained in the tobacco stick 15 may decrease more quickly. Therefore, the control unit 120 monitors statistics related to inhalation at least in section S4 (or sections after section S2). In the following description, the statistics to be monitored are also simply referred to as control parameters. The control parameters here may be the number of inhalation detections, the inhalation detection frequency, or the accumulated inhalation time. Then, when the control parameters satisfy a predetermined condition, the control unit 120 transitions the temperature control from section S4 to section S5. The predetermined condition will be described later with some examples. Even if the control parameters do not satisfy the predetermined condition, the control unit 120 transitions the temperature control from section S4 to section S5 when a predetermined time has elapsed from the reference time point. The reference time point may typically be the start time of section S4 (T4 in FIG. 6). Alternatively, the reference time point may be the time point when the end of pre-heating is notified to the user (T2 in FIG. 6).

[0063] <2-6. Reheating (S5)> Section S5 is a section for increasing the temperature of the heating unit 130 from the second temperature H2 to the third temperature H3. In section S5, PID control is performed, and the target value is increased approximately linearly, in practice, stepwise for each control cycle, so that the temperature of the heating unit 130 gradually increases to the third temperature H3 from the start of the section to the end of the section. The gain of the PID control in section S5 may be the same as or different from that in section S4. As shown in FIG. 6, if the transition from section S4 to section S5 occurs at T5, section S5 ends at T6. If the transition from section S4 to section S5 occurs earlier, the end time of section S5 may be different in various embodiments described later. The temperature increase rate of the heating unit 130 in section S5 is equal to the gradient of the target value of the PID control as long as stable control continues. The gradient of the target value may be predefined as the amount of change in the target value for each control cycle, or may be derived by dividing the difference between the measured temperature at the start of the section and the target temperature at the end of the section by the time length of section S5. Section S5 ends when the temperature of the heating unit 130 reaches the third temperature H3.

[0064] <2-7. Maintaining temperature after reheating (S6)> Section S6 is a section for maintaining the temperature of the heating unit 130 near the third temperature H3. In section S6, PID control is performed by setting the target value of the temperature control to a resistance value (hereinafter referred to as R3) corresponding to the third temperature H3. The gain of the PID control in section S6 may be the same as in sections S1, S2, and S4. Section S6 ends when a time length that may be set to a value within a range of several tens of seconds has elapsed.

[0065] <2-8.End (S7)> Section S7 is the final section of the heating period. In section S7, the control unit 120 stops the supply of power from the battery 140 to the heating unit 130 so that the temperature of the heating unit 130 drops toward the environmental temperature H0. That is, section S7 is an off section. Section S7 ends when a time length that can be set to a value within a range of several seconds to several tens of seconds has elapsed. At the start of section S7, the control unit 120 may notify the user that the end of the inhalation period is approaching by emitting light from the light-emitting unit 125 or vibrating the vibration unit 126. Furthermore, at the end of section S7, the control unit 120 may notify the user that the inhalation period has ended by emitting light from the light-emitting unit 125 or vibrating the vibration unit 126.

[0066] <<3. Control of reheating behavior>> According to the above-mentioned heating profile 50, the section S4, which is the temperature maintenance section after the temperature is lowered to the second temperature H2, ends at the latest when a predetermined time has elapsed from the reference time point (T5 in FIG. 6), and the temperature control transitions to the section S5, which is the re-heating section. However, the timing of this transition will be earlier if the statistics regarding the user's inhalation satisfy a predetermined condition. In the following description, the case in which the transition from the section S4 to the section S5 occurs when a predetermined time has elapsed from the reference time point is called "normal transition", and the case in which the transition occurs earlier is called "early transition". In this embodiment, the content of the temperature control after the section S5 is made different between the normal transition and the early transition, thereby further improving the quality of the inhalation experience of the user. For example, if the statistics indicate that the user's inhalation pace is fast, the temperature of the heating unit 130 can be made to reach the third temperature H3 at an early timing appropriate to that pace, so that the user can feel the improvement in the smoking taste brought about by the re-heating. If the pace of inhalation by the user is slow, the temperature of the heating unit 130 can be allowed to reach the third temperature H3 over a designed period of time, thereby providing the user with an inhalation experience for a longer period of time. In this section, several embodiments for realizing different temperature profiles depending on statistics regarding inhalation will be described.

[0067] <3-1. Conditions for early transition> Before describing each embodiment, some examples of conditions for early transition will be presented for each type of monitored statistics. As described above, the statistics regarding the user's inhalation may be, for example, the number of times that inhalation is detected, the frequency of inhalation detection, or the cumulative inhalation time.

[0068] When the number of detected puffs is monitored as a control parameter, the condition for the early transition may include the number of detected puffs reaching a first transition threshold. For example, if the amount of the aerosol source contained in the tobacco stick 15 is an amount that allows M puffs, assuming an average length and strength of puffs, the first transition threshold may be set to a value of M / 2 or more. This means that half of the aerosol source contained in the tobacco stick 15 has already been consumed when the number of detected puffs reaches the first transition threshold. In this case, by performing the re-heating in the section S5 more quickly than in the case of the normal transition, it is possible to reduce the possibility that the improvement in smoking taste brought about by the re-heating will be missed in time. As an example, when M>3, the first transition threshold may be set to M-1. This means that when the number of detected puffs reaches the first transition threshold, the aerosol source contained in the tobacco stick 15 is in a state where it will be depleted if the user takes one more puff. In this case, by performing the re-heating quickly, it is possible to increase the temperature of the heating unit 130 as much as possible during the user's last puff, thereby ensuring that the user can enjoy a sufficient smoking taste at the end of the session.

[0069] When the inhalation detection frequency is monitored as a control parameter, the condition for the early transition may include that the inhalation detection frequency exceeds a second transition threshold. The inhalation detection frequency is obtained by dividing the number of inhalation detections by the length of the monitoring period. At the beginning of the section, the denominator for frequency calculation is small and the value of the control parameter is not stable, so the determination of the section transition in this case may not be made until a certain amount of time has passed since the start of the section. For example, the second transition threshold may be set to a value such that if inhalation is continued at that frequency, the number of inhalation detections will reach the upper limit before the arrival of T6. This means that when the inhalation detection frequency exceeds the second transition threshold, there is a high possibility that the aerosol source contained in the tobacco stick 15 will be depleted before the section S6. In this case, by performing the re-heating in section S5 more quickly than in the case of normal transition, it is possible to reduce the possibility that the improvement in smoking taste brought about by the re-heating will be missed in time.

[0070] When the cumulative inhalation time is monitored as a control parameter, the condition for the early transition may include that the cumulative inhalation time reaches a third transition threshold. For example, the amount of the aerosol source contained in the tobacco stick 15 is the amount consumed by inhalation over a total time L, assuming an average inhalation strength. In this case, the third transition threshold may be set to a value greater than L / 2. This means that when the cumulative inhalation time reaches the third transition threshold, half of the aerosol source contained in the tobacco stick 15 has already been consumed. In this case, by performing the re-heating in section S5 more quickly than in the case of the normal transition, it is possible to reduce the possibility that the improvement in smoking taste brought about by the re-heating will be missed in time.

[0071] In the embodiments and modifications described in the following sections, the control unit 120 counts the number of suction detections from the time when the end of preheating is notified to the user (T2 in FIG. 6) or from the time when section S4 starts (T4 in FIG. 6), and monitors this as a control parameter. However, in any of the embodiments and modifications, the suction detection frequency or the accumulated suction time may be monitored instead of the number of suction detections, or a composite control parameter that combines two or more of these may be monitored.

[0072] <3-2. First Example> FIG. 7 shows an example of a temperature profile 41 that can be realized in the first embodiment, in comparison with the temperature profile 40 during normal transition shown in FIG. puff represents the time point at which it is determined that the number of suction detections satisfies the above-mentioned predetermined condition, and is earlier than T5, which is the time point at which the maximum time length set for the section S4 has elapsed. puff In response to determining that the number of suction detections satisfies the above-mentioned predetermined condition in the period S1, the control unit 120 immediately transitions the temperature control to period S5. In the case of this early transition, the control unit 120 performs the temperature control in period S5 so that the temperature of the heating unit 130 reaches the third temperature H3 at T5a, which is earlier than T6, the time at which the temperature of the heating unit 130 would have reached the third temperature H3 in the case of a normal transition. puff The time length from T5 to T5a is equal to the time length from T5 to T6, and therefore the gradient of the target value of the PID control in section S5 is the same in both the normal transition and early transition cases. According to the first embodiment, it is possible to achieve improvement in smoking taste at an early timing by utilizing the same settings as in the normal transition case, without the need to set a separate temperature rise rate and re-tune the gain.

[0073] <3-3. Second Example> FIG. 8 shows an example of a temperature profile 42 that can be realized in the second embodiment, in comparison with the temperature profile 40 during normal transition shown in FIG. 6. In the second embodiment, the control unit 120 puff In response to determining that the number of suction detections satisfies the above-mentioned predetermined condition in section S1, the control unit 120 immediately transitions the temperature control to section S5. In the case of this early transition, the control unit 120 performs temperature control in section S5 so that the temperature of the heating unit 130 reaches the third temperature H3 at T5b, which is earlier than T6, the time at which the temperature of the heating unit 130 would have reached the third temperature H3 in the case of a normal transition. puffThe time length from T5 to T5b is shorter than the time length from T5 to T6. Therefore, the gradient of the target value of the PID control in section S5 in the case of the early transition is steeper than that in the case of the normal transition, which means that the temperature rise rate of the heating unit 130 is higher. According to the second embodiment, the target temperature reaches the third temperature H3 in a shorter time than in the first embodiment, so that the user can have a sufficient time to enjoy a good inhalation experience after the re-heating is completed.

[0074] <3-4. Third Example> FIG. 9 shows an example of a temperature profile 43 that can be realized in the third embodiment, in comparison with the temperature profile 40 during normal transition shown in FIG. 6. In the third embodiment, the control unit 120 puff In response to determining that the number of suction detections satisfies the above-mentioned predetermined condition in section S1, the control unit 120 immediately transitions the temperature control to section S5. In the case of this early transition, the control unit 120 performs temperature control in section S5 so that the temperature of the heating unit 130 reaches the third temperature H3 at T5c, which is earlier than T6, the time at which the temperature of the heating unit 130 would have reached the third temperature H3 in the case of a normal transition. puff The time length from T5 to T5c is longer than the time length from T5 to T6. Therefore, the gradient of the target value of the PID control in section S5 in the case of this early transition is gentler than that in the case of normal transition, which means that the temperature rise rate of the heating unit 130 is lower. According to the third embodiment, the load on the battery 140 during re-warming is suppressed compared to the first and second embodiments, so that it is possible to minimize the possibility of malfunction caused by voltage drop (temporary voltage drop during power output).

[0075] <3-5. Fourth Example> FIG. 10 shows an example of a temperature profile 44 that can be realized in the fourth embodiment, in comparison with the temperature profile 40 during normal transition shown in FIG. 6. In the fourth embodiment, the control unit 120 puffIn response to the determination that the number of suction detections satisfies the above-mentioned predetermined condition, the temperature control waits for a delay time dT instead of immediately transitioning to section S5. trans (=T puff The temperature control is transitioned to section S5 at the delay time dT. puff In the case of this early transition, the control unit 120 performs temperature control for the section S5 so that the temperature of the heating unit 130 reaches the third temperature H3 at T5d, which is earlier than T6, the time at which the temperature of the heating unit 130 would reach the third temperature H3 in the case of a normal transition. trans The time length from T5 to T5d is equal to the time length from T5 to T6, so the gradient of the target value of the PID control in section S5 is the same in both the normal transition and early transition cases. According to the fourth embodiment, similar to the first embodiment, the same settings as in the normal transition case can be used in the early transition case without the need for separate temperature rise rate settings and gain retuning. In addition, since there is generally a trade-off between the early reheating and the duration of the smoking taste, providing such a delay time rather than immediately transitioning the temperature control can also contribute to optimizing the user's inhalation experience.

[0076] <3-6. Fifth Example> FIG. 11 shows a temperature profile 45 as an example that can be realized in the fifth embodiment, in comparison with the temperature profile 40 during normal transition shown in FIG. 6. In the fifth embodiment, the control unit 120 also puff After determining that the number of suction detections satisfies the above-mentioned predetermined condition, the device waits for a delay time dT, and trans (=T puff In the case of this early transition, the control unit 120 performs the temperature control in the section S5 so that the temperature of the heating unit 130 reaches the third temperature H3 at T5e, which is earlier than T6, which is the time point at which the temperature of the heating unit 130 would reach the third temperature H3 in the case of a normal transition. transThe time length from T5 to T5e is shorter than the time length from T5 to T6. Therefore, the gradient of the target value of the PID control in section S5 in the case of the early transition is steeper than that in the case of the normal transition, which means that the temperature rise rate of the heating unit 130 is higher. According to the fifth embodiment, the target temperature reaches the third temperature H3 in a shorter time than in the fourth embodiment, so that a sufficient time can be secured for the user to enjoy a good inhalation experience after the re-heating is completed.

[0077] <3-7. Sixth Example> FIG. 12 shows a temperature profile 46 as an example that can be realized in the sixth embodiment, in comparison with the temperature profile 40 during normal transition shown in FIG. 6. In the sixth embodiment, the control unit 120 also puff After determining that the number of suction detections satisfies the above-mentioned predetermined condition, the device waits for a delay time dT, and trans (=T puff In the case of this early transition, the control unit 120 performs the temperature control in the section S5 so that the temperature of the heating unit 130 reaches the third temperature H3 at T5f, which is earlier than T6, which is the time point at which the temperature of the heating unit 130 would reach the third temperature H3 in the case of a normal transition. trans The time length from T5 to T5f is longer than the time length from T5 to T6. Therefore, the gradient of the target value of the PID control in section S5 in the case of the early transition is gentler than that in the case of the normal transition, which means that the temperature rise rate of the heating unit 130 is lower. According to the sixth embodiment, the load on the battery 140 during the re-warming is suppressed compared to the fourth and fifth embodiments, so that the possibility of malfunction caused by the drop voltage can be reduced as much as possible.

[0078] <3-8. Seventh Example> FIG. 13 shows a temperature profile 47 as an example that can be realized in the seventh embodiment, in comparison with the temperature profile 40 during normal transition shown in FIG. 6. In the seventh embodiment, the control unit 120 puffIn response to determining that the number of suction detections satisfies the above-mentioned predetermined condition in the section S4, the control unit 120 waits until T5 and then transitions the temperature control to the section S5. However, the control unit 120 performs the temperature control in the section S5 so that the temperature of the heating unit 130 reaches the third temperature H3 at T5g, which is earlier than T6, the time when the temperature of the heating unit 130 should reach the third temperature H3 in the case of normal transition. In the seventh embodiment, the transition timing from the section S4 to the section S5 is equal to T5 regardless of whether the above-mentioned predetermined condition is satisfied, so that it does not match the definition of early transition described above. However, this is also treated as an early transition in that the timing when the temperature of the heating unit 130 reaches the third temperature H3 is brought forward and the transition to the section S6 is earlier. The time length from T5 to T5g is shorter than the time length from T5 to T6. Therefore, the gradient of the target value of the PID control in the section S5 in the case of this early transition is steeper than that in the case of normal transition, which means that the temperature rise rate of the heating unit 130 is higher. According to the seventh embodiment, it is possible to make the target temperature reach the third temperature H3 in a shorter time than in the case of the normal transition.

[0079] <3-9. Eighth Example> 7 to 13 show examples in which even in the case of an early transition, section S6 ends at T7 like a normal transition, but in each of the first to seventh embodiments, the control unit 120 may end section S6 after an early transition at a point in time earlier than the point in time at which section S6 ends after a normal transition. FIG. 14 shows a temperature profile 48 as an example according to such an eighth embodiment. In the eighth embodiment, the control unit 120 determines whether or not section S6 ends at T puffIn response to determining that the number of suction detections satisfies the predetermined condition in step S1, the control unit 120 immediately transitions the temperature control to section S5, and performs temperature control in section S5 so that the temperature of the heating unit 130 reaches the third temperature H3 at T5a, which is earlier than T6, as in the first embodiment. Then, the control unit 120 performs temperature control in section S6 from T5a to T7a (i.e., maintaining the temperature after reheating), and transitions the temperature control to section S7 at T7a to stop the supply of power from the battery 140 to the heating unit 130. T7a is earlier than T7, which is the time when the supply of power to the heating unit 130 is stopped in the case of a normal transition. The earlier this T7a is, the more the total power consumed in one session is reduced.

[0080] In the eighth embodiment, the control unit 120 may determine the timing T7a at which the supply of power to the heating unit 130 is stopped, depending on the value of a monitored control parameter. For example, when the number of detected puffs reaches an upper limit M, the control unit 120 may end the section S6 and stop the supply of power to the heating unit 130. Furthermore, when the accumulated puff time reaches an upper limit L, the control unit 120 may end the section S6 and stop the supply of power to the heating unit 130. This makes it possible to avoid unnecessary consumption of power in a situation where only a small aerosol source remains in the tobacco stick 15.

[0081] <3-10. Variations> It is also possible to envision a modified example that combines the above-mentioned embodiments. In a first modified example, the control unit 120 puff If it is determined that the above-mentioned specified conditions are met, T puffDepending on the statistics related to the suction measured up to the end of the period, different control contents may be selectively applied to the temperature control of the section S5. For example, when a suction detection frequency (or a longer cumulative suction time) higher than a certain threshold is measured, the control unit 120 may apply a high temperature rise rate to the temperature control of the section S5 as in the second embodiment, and when a suction detection frequency (or a shorter cumulative suction time) lower than the threshold is measured, the control unit 120 may apply a normal temperature rise rate to the temperature control of the section S5 as in the first embodiment. Also, for example, when a suction detection frequency (or a longer cumulative suction time) higher than a certain threshold is measured, the control unit 120 may immediately transition the temperature control to the section S5 as in the first, second or third embodiment, and when a suction detection frequency (or a shorter cumulative suction time) lower than the threshold is measured, the control unit 120 may transition the temperature control to the section S5 after waiting for the delay time dT as in the fourth, fifth or sixth embodiment.

[0082] In the second modification, the control unit 120 puff If it is determined that the above-mentioned specified conditions are met, T puff The delay time dT may be changed depending on the length of the remaining time from T to T5. For example, the control unit 120 may change the delay time dT depending on the length of the remaining time from T to T5. puff The product of the remaining time from T to T5 and a predetermined ratio α (0<α<1) may be set as the delay time dT, and the temperature control may be transitioned to section S5 after waiting for the delay time dT. This allows for more flexible adjustment of the transition timing of the temperature control.

[0083] In addition, in this section, an example has been described in which the temperature rise rate of the heating unit 130 is variably controlled by increasing or decreasing the gradient (amount of change per control cycle) of the target value of the PID control in section S5. However, the control unit 120 may also control the temperature rise rate of the heating unit 130 by increasing or decreasing the gain value while maintaining the target value of the PID control constant in section S5.

[0084] <<4. Processing flow>> In this section, several examples of the flow of the temperature control process executed by the control unit 120 of the above-mentioned aerosol generation device 10 will be described with reference to flowcharts. In the following description, a processing step will be abbreviated as S (step).

[0085] <4-1. Temperature control process in section S4> (1) First Example 15 is a flow chart showing a first example of the flow of a temperature control process that can be executed in section S4, which is a temperature maintenance section after the temperature is lowered. This first example can correspond to the first, second, third or eighth embodiment described above.

[0086] First, in S111, the control unit 120 sets the PID control parameters and time length of the current section according to the heating profile 50. The PID control parameters set here may include, for example, a target temperature resistance value, a proportional gain, an integral gain, and a differential gain.

[0087] The subsequent steps S112 to S120 are repeated for each control cycle. First, in S112, the control unit 120 uses the measurement circuit 150 to acquire a first temperature index based on the electrical resistance value of the heating unit 130. The index value acquired here may be, for example, an average value of the results of multiple resistance value measurements, as described with reference to FIG. 5. Then, in S113, the control unit 120 acquires the latest value of a statistic related to suction (for example, the number of suction detections). Then, in S114, the control unit 120 acquires the value of a timer that was started at the start of section S2 or section S4.

[0088] Next, in S115, the control unit 120 determines whether the time length set in S111 has elapsed based on the timer value acquired in S114. If the set time length has not yet elapsed, the process proceeds to S117. In S117, the control unit 120 determines whether the suction-related statistics acquired in S113 satisfy the above-mentioned predetermined condition. If the suction-related statistics do not satisfy the predetermined condition, the temperature control process for section S4 continues, and the process proceeds to S118.

[0089] In S118, control unit 120 calculates the PWM duty ratio for the latest control cycle according to the PID control equation described using equation (2). Next, in S119, control unit 120 outputs a control pulse having a pulse width based on the calculated duty ratio to first switch 131 and second switch 132, thereby supplying power from battery 140 to heating unit 130. Next, in S120, control unit 120 updates the statistics regarding suction of the monitored object based on the suction detection signal input from suction detection unit 124.

[0090] When one control cycle ends in this way, the process proceeds to the next control cycle, and the above-mentioned steps S112 to S120 are repeated. When it is determined in S115 that the set time period has elapsed, or when it is determined in S117 that the suction-related statistics satisfy a predetermined condition, the control unit 120 ends the temperature control process of section S4 shown in Fig. 15, and transitions the temperature control to the next section S5.

[0091] (2) Second Example 16 is a flow chart showing a second example of the flow of the temperature control process that can be executed in section S4, which is the temperature maintenance section after the temperature is lowered. This second example can correspond to the fourth, fifth, sixth or seventh embodiment described above.

[0092] First, in S111, the control unit 120 sets the PID control parameters and time length of the current section according to the heating profile 50. The PID control parameters set here may include, for example, a target temperature resistance value, a proportional gain, an integral gain, and a differential gain.

[0093] Thereafter, steps S112 to S120 are repeated for each control cycle. First, in S112, the control unit 120 uses the measurement circuit 150 to obtain a first temperature index based on the electrical resistance value of the heating unit 130. Then, in S113, the control unit 120 obtains the latest value of the suction-related statistics. Then, in S114, the control unit 120 obtains the value of the timer that was started at the start of section S2 or section S4.

[0094] Next, in S115, the control unit 120 determines whether the time length set in S111 has elapsed based on the timer value acquired in S114. If the set time length has not yet elapsed, the process proceeds to S116. In S116, the control unit 120 determines whether the current state of the temperature control is a transition standby state (i.e., during the delay time dT). At the beginning of the section S4, the control state is not a transition standby state, and the process proceeds to S117. In S117, the control unit 120 determines whether the suction-related statistics acquired in S113 satisfy the above-mentioned predetermined condition. If the suction-related statistics satisfy the predetermined condition, the temperature control enters a transition standby state in S121. If the suction-related statistics do not satisfy the predetermined condition, S121 is skipped.

[0095] Next, in S118, control unit 120 calculates the PWM duty ratio for the latest control cycle according to the PID control equation described using equation (2) regardless of whether it is in the transition standby state. Next, in S119, control unit 120 outputs a control pulse having a pulse width based on the calculated duty ratio to first switch 131 and second switch 132, thereby supplying power from battery 140 to heating unit 130. Next, in S120, control unit 120 updates the statistics regarding suction of the monitored object based on the suction detection signal input from suction detection unit 124.

[0096] When one control cycle ends in this way, the process proceeds to the next control cycle, and the above-mentioned S112 to S120 are repeated. When the control unit 120 determines in S115 that the set time length has elapsed, it ends the temperature control process for section S4 and transitions the temperature control to the next section S5. When the control unit 120 determines in S116 that the current state of the temperature control is a transition waiting state, it further determines in S122 whether or not the delay time dT has elapsed, and when it determines that the delay time dT has elapsed, it ends the temperature control process for section S4 and transitions the temperature control to the next section S5. On the other hand, when it is determined in S122 that the delay time dT has not elapsed, the process proceeds to S118, and the temperature control process for section S4 continues.

[0097] <4-2. Temperature control process in section S5> FIG. 17 is a flowchart showing an example of the flow of a temperature control process that can be executed in section S5, which is the re-heating section.

[0098] First, in S131, the temperature control process for section S5 branches depending on whether the transition from section S4 to section S5 was a normal transition or an early transition. If the transition from section S4 to section S5 was a normal transition, the process proceeds to S132. On the other hand, if the transition from section S4 to section S5 was an early transition, the process proceeds to S133.

[0099] In the case of a normal transition, in S132, the control unit 120 sets the PID control parameters and the temperature rise rate (the amount of change in the target value for each control cycle) for the current section to default values ​​according to the heating profile 50. On the other hand, in the case of an early transition, in S133, the control unit 120 sets the PID control parameters and the temperature rise rate for the current section to values ​​for causing the temperature of the heating unit 130 to reach the third temperature H3 earlier than in the case of a normal transition.

[0100] The subsequent steps S134 to S139 are repeated for each control cycle. First, in S134, the control unit 120 uses the measurement circuit 150 to obtain a first temperature index based on the electrical resistance value of the heating unit 130. In addition, in S135, the control unit 120 obtains the value of the timer that was started at the start of section S5.

[0101] Next, in S136, the control unit 120 determines whether the target value of the temperature control, which is increased for each control cycle, has reached the third temperature. If it is determined that the target value of the PID control has not reached the third temperature, the process proceeds to S137. Note that the determination in S136 may be replaced by a determination of whether the timer value has reached the time length of section S5 (which may differ between normal transition and early transition). In S137, the control unit 120 increases the target value of the PID control according to the temperature increase rate set in S132 or S133.

[0102] Next, in S138, the control unit 120 calculates the PWM duty ratio for the latest control cycle according to the PID control formula described using formula (2). Next, in S139, the control unit 120 outputs a control pulse having a pulse width based on the calculated duty ratio to the first switch 131 and the second switch 132, thereby supplying power from the battery 140 to the heating unit 130.

[0103] When one control cycle ends in this way, the process proceeds to the next control cycle, and the above-mentioned S134 to S139 are repeated. When the control unit 120 determines in S136 that the target value of the PID control has reached the third temperature, it ends the temperature control process of section S5 shown in Fig. 17, and transitions the temperature control to the next section S6.

[0104] <<5. Summary>> Various embodiments and modifications of the present disclosure have been described above with reference to Figs. 1 to 17. According to the technology of the present disclosure, when a statistic such as the number of suction detections, the suction detection frequency, or the cumulative suction time satisfies a predetermined condition in the temperature maintenance section after the temperature is lowered, not only is a transition to the reheating section performed, but the temperature of the reheating section is controlled so that the timing of the completion of the reheating is different from that in normal times. Therefore, it is possible to provide the user with an improved suction experience, such as allowing the user to reliably experience the improvement in the smoking taste brought about by the reheating.

[0105] The invention is not limited to the above-described embodiment, and various modifications and variations are possible within the scope of the gist of the invention.

Claims

1. A heating unit that heats the aerosol source to generate an aerosol; A power source for supplying power to the heating unit; A detection unit that detects inhalation of the aerosol by a user; Supplying power from the power source to the heating unit, a first section in which a target value of the temperature control of the heating unit is set to a value corresponding to a first temperature and power is supplied from the power source to the heating unit; a second section following the first section, in which a target value of the temperature control of the heating unit is set to a value corresponding to a second temperature lower than the first temperature, and power is supplied from the power source to the heating unit; and a third section following the second section, in which a target value of the temperature control of the heating unit is set to a value corresponding to a third temperature higher than the second temperature, and power is supplied from the power source to the heating unit; A control unit that performs control according to a control sequence including at least Equipped with The control unit is monitoring a detection count representing a number of times the suction is detected by the detection unit at least in the second section; When the number of detections does not satisfy a predetermined condition, the temperature control is transitioned to the third section at a first point in time when a predetermined time has elapsed from a reference point in time, and the temperature control is performed so that the temperature of the heating unit reaches the third temperature at a second point in time after a certain length of time has elapsed; When the number of detections satisfies the predetermined condition, the temperature control is transitioned to the third section at a third time point, and the temperature control is performed so that the temperature of the heating unit reaches the third temperature at a fourth time point that is earlier than the second time point. The predetermined condition includes that the number of detections reaches a threshold value. Aerosol generating device.

2. The aerosol generating device according to claim 1 , wherein the third time point is earlier than the first time point.

3. The aerosol generating device according to claim 2 , wherein the third point in time is a point in time when the control unit determines that the number of detections satisfies the predetermined condition.

4. The aerosol generating device of claim 2, wherein the third point in time is a point in time that is shorter than the remaining time until the first point in time after the control unit determines that the number of detections satisfies the specified condition.

5. The aerosol generating device of claim 1 , wherein the third point in time is equal to the first point in time.

6. The aerosol generating device of any one of claims 1 to 5, wherein the control unit performs the temperature control so that the temperature rise rate of the heating unit in the third zone is higher when the temperature control is transitioned to the third zone as a result of the number of detections satisfying the specified condition, compared to when the temperature control is transitioned to the third zone without the number of detections satisfying the specified condition.

7. The aerosol generating device of claim 3 or 4, wherein the control unit performs the temperature control so that when the temperature control is transitioned to the third zone as a result of the number of detections satisfying the specified condition, the temperature rise rate of the heating unit in the third zone is lower than when the temperature control is transitioned to the third zone without the number of detections satisfying the specified condition.

8. The aerosol generating device comprises: a receiving portion for receiving a tobacco article including the aerosol source; Further comprising: the tobacco article includes an aerosol source in an amount that allows M inhalations of the aerosol, where M is an integer greater than or equal to 2; The threshold is equal to or greater than M / 2. The aerosol generating device according to claim 1 .

9. The aerosol generating device according to any one of claims 1 to 8, wherein the control unit selects the temperature rise rate of the heating unit in the third section depending on the frequency at which the inhalation is detected or the cumulative value of the time over which the inhalation is detected when the number of detections satisfies the specified condition.

10. The aerosol generating device of claim 4, wherein the control unit determines the third point in time at which the temperature control is transitioned from the second zone to the third zone in accordance with the remaining time until the first point in time when the number of detections satisfies the specified condition.

11. The aerosol generating device according to any one of claims 1 to 10, wherein the control unit counts the number of detections from the point at which the end of preheating is notified to the user or the point at which the second section begins.

12. A heating unit that heats the aerosol source to generate an aerosol; A power source for supplying power to the heating unit; A detection unit that detects inhalation of the aerosol by a user; Supplying power from the power source to the heating unit, a first section in which a target value of the temperature control of the heating unit is set to a value corresponding to a first temperature and power is supplied from the power source to the heating unit; a second section following the first section, in which a target value of the temperature control of the heating unit is set to a value corresponding to a second temperature lower than the first temperature, and power is supplied from the power source to the heating unit; and a third section following the second section, in which a target value of the temperature control of the heating unit is set to a value corresponding to a third temperature higher than the second temperature, and power is supplied from the power source to the heating unit; A control unit that performs control according to a control sequence including at least Equipped with The control unit is monitoring a detection frequency indicating a frequency at which the suction is detected by the detection unit at least in the second section; When the detection frequency does not satisfy a predetermined condition, the temperature control is transitioned to the third section at a first point in time when a predetermined time has elapsed from a reference point in time, and the temperature control is performed so that the temperature of the heating unit reaches the third temperature at a second point in time after a certain length of time has elapsed; When the detection frequency satisfies the predetermined condition, the temperature control is transitioned to the third section at a third time point, and the temperature control is performed so that the temperature of the heating unit reaches the third temperature at a fourth time point that is earlier than the second time point. The predetermined condition includes that the detection frequency exceeds a threshold value. Aerosol generating device.

13. A heating unit that heats the aerosol source to generate an aerosol; A power source for supplying power to the heating unit; A detection unit that detects inhalation of the aerosol by a user; Supplying power from the power source to the heating unit, a first section in which a target value of the temperature control of the heating unit is set to a value corresponding to a first temperature and power is supplied from the power source to the heating unit; a second section following the first section, in which a target value of the temperature control of the heating unit is set to a value corresponding to a second temperature lower than the first temperature, and power is supplied from the power source to the heating unit; and a third section following the second section, in which a target value of the temperature control of the heating unit is set to a value corresponding to a third temperature higher than the second temperature, and power is supplied from the power source to the heating unit; A control unit that performs control according to a control sequence including at least Equipped with The control unit is monitoring an accumulated suction time representing an accumulated value of a time during which the suction is detected by the detection unit at least in the second section; When the accumulated suction time does not satisfy a predetermined condition, the temperature control is transitioned to the third section at a first point in time when a predetermined time has elapsed from a reference point in time, and the temperature control is performed so that the temperature of the heating part reaches the third temperature at a second point in time after a certain length of time has elapsed; When the accumulated suction time satisfies the predetermined condition, the temperature control is transitioned to the third section at a third time point, and the temperature control is performed so that the temperature of the heating unit reaches the third temperature at a fourth time point that is earlier than the second time point. The predetermined condition includes that the cumulative suction time reaches a threshold value. Aerosol generating device.

14. 1. An aerosol generating device including a heating unit that generates an aerosol by heating an aerosol source, a power source that supplies power to the heating unit, and a detection unit that detects inhalation of the aerosol by a user, comprising: a control method for controlling the supply of power from the power source to the heating unit in accordance with a control sequence, the method comprising: The control sequence includes: a first section in which a target value of the temperature control of the heating unit is set to a value corresponding to a first temperature and power is supplied from the power source to the heating unit; a second section following the first section, in which a target value of the temperature control of the heating unit is set to a value corresponding to a second temperature lower than the first temperature, and power is supplied from the power source to the heating unit; and a third section following the second section, in which a target value of the temperature control of the heating unit is set to a value corresponding to a third temperature higher than the second temperature, and power is supplied from the power source to the heating unit; At least The control method includes: monitoring a detection count representing a number of times the suction is detected by the detection unit at least in the second section; When the number of detections does not satisfy a predetermined condition, the temperature control is transitioned to the third section at a first point in time when a predetermined time has elapsed from a reference point in time, and the temperature control is performed so that the temperature of the heating unit reaches the third temperature at a second point in time after a certain length of time has elapsed. When the number of detections satisfies the predetermined condition, the temperature control is transitioned to the third section at a third time point, and the temperature control is performed so that the temperature of the heating unit reaches the third temperature at a fourth time point earlier than the second time point. Including, The predetermined condition includes that the number of detections reaches a threshold value. Control methods.

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