Aerosol generation device

Abstract

[Problem] To provide a mechanism making it possible to further improve the quality of user experience. [Solution] An aerosol generation device is provided with: an accommodating section in an interior space of which a substrate containing an aerosol source is accommodated; a load for heating the substrate; an impedance circuit comprising a pair of electrodes for detecting the capacitance of the interior space of the accommodating section; a signal generator for generating an input signal to be inputted to the impedance circuit; and a control unit for starting the heating by the load on the basis of the voltage of an output signal from the impedance circuit. The pair of electrodes are arranged further up than the load; and the vertical length of the pair of electrodes and / or the frequency of the input signal is set on the basis of the vertical length of a portion of the substrate where the aerosol source is distributed.

Description

Aerosol Generator

[0001] The present disclosure relates to an aerosol generating device.

[0002] Aerosol generating devices that generate aerosols to be inhaled by users are widely used. For example, an aerosol generating device generates aerosols imparted with flavor components using a base material containing an aerosol source for generating aerosols and a flavor source for imparting flavor components to the generated aerosol. A user can enjoy the flavor by inhaling the aerosol imparted with flavor components generated by the aerosol generating device. The action of a user inhaling the aerosol is hereinafter also referred to as a puff or a puffing action. An example of a device classified as an aerosol generating device is a heated tobacco product, which is used instead of a so-called cigarette. Note that a heated tobacco product is an aerosol generating device that generates aerosol by heating an aerosol source.

[0003] Regarding an aerosol generating device of the type that heats an inserted substrate, a technology for detecting the insertion of a substrate has been developed. For example, Patent Document 1 listed below discloses a technology in which electrodes are arranged in positions surrounding the inserted substrate, and whether or not a substrate has been inserted is determined based on the rate of increase and decrease in voltage when a step of applying a voltage to the electrode and a step of releasing the voltage from the electrode are repeated.

[0004] Patent No. 6348985

[0005] However, the technology disclosed in the above-mentioned Patent Document 1 has only recently been developed, and there is still room for improvement in various respects.

[0006] Therefore, the present disclosure has been made in consideration of the above problems, and an object of the present disclosure is to provide a mechanism that can further improve the quality of the user experience.

[0007] In order to solve the above problems, according to one aspect of the present disclosure, there is provided an aerosol generation device comprising: a storage unit having an opening on an upper side through which a substrate containing an aerosol source can be inserted and removed in the vertical direction and which stores the substrate in an internal space; a load that generates energy for heating the aerosol source of the substrate stored in the storage unit; an impedance circuit including a pair of electrodes that detects the capacitance of the internal space of the storage unit; a signal generator that generates an input signal to be input to the impedance circuit; a comparator that compares the voltage of the output signal from the impedance circuit with a threshold voltage; and a control unit that controls the operation of the load based on the output from the comparator, wherein the pair of electrodes are positioned above the load, and at least one of the vertical lengths of the pair of electrodes and the frequency of at least one signal among the one or more signals that make up the input signal is set based on the vertical length of a portion of the substrate in which the aerosol source is distributed, and the control unit starts the generation of energy by the load when the output from the comparator satisfies a predetermined condition.

[0008] The pair of electrodes may be disposed above a portion of the substrate where an aerosol source is distributed, when the substrate is completely inserted into the container.

[0009] The signal generator may set the frequency of at least one of the one or more signals constituting the input signal so that one or more periods are included in the determination period in which the amount of the aerosol source present between the pair of electrodes is at its maximum, calculated based on the vertical length of the pair of electrodes, the vertical length of the portion of the substrate in which the aerosol source is distributed, and the expected insertion speed of the substrate into the storage section.

[0010] The control unit may set the frequency of at least one of the one or more signals that make up the input signal based on the time during which the capacitance of the pair of electrodes changes, measured when the user inserts the substrate into the storage unit.

[0011] The impedance circuit may be a filter circuit.

[0012] The filter circuit may be designed so that the cutoff frequency when the amount of the aerosol source present between the pair of electrodes is at a maximum corresponds to the frequency of at least one of the one or more signals that constitute the input signal.

[0013] The signal generator, the pair of electrodes and the comparator may form part of a series circuit.

[0014] The wiring between the pair of electrodes may be shielded by a GND potential.

[0015] The impedance circuit may further include an amplifier that amplifies the output signal.

[0016] The amplifier may operate intermittently.

[0017] The amplifier may operate intermittently at a period corresponding to the length of the determination period during which the amount of the aerosol source present between the pair of electrodes is at its maximum, calculated based on the vertical length of the pair of electrodes, the vertical length of the portion of the substrate in which the aerosol source is distributed, and the expected insertion speed of the substrate into the storage section.

[0018] The input signal may be a sine wave.

[0019] The load may be a heating section.

[0020] As described above, the present disclosure provides a mechanism that can further improve the quality of the user experience.

[0021] 7 is a schematic diagram showing an example of the configuration of an aerosol generation device. FIG. 8 is a diagram for explaining an overview of the aerosol generation device according to the present embodiment. FIG. 9 is a diagram showing an example of the configuration of a control circuit. FIG. 10 is a diagram showing an example of the configuration of an impedance circuit. FIG. 11 is a graph showing an example of the gain characteristics of the impedance circuit shown in FIG. 4. FIG. 12 is a graph showing an example of time-series changes in output voltage accompanying the insertion of a stick-shaped substrate. FIG. 13 is a diagram showing another example of the configuration of an impedance circuit. FIG. 14 is a graph showing an example of the gain characteristics of the impedance circuit shown in FIG. 15. FIG. 16 is a diagram showing another example of the configuration of an impedance circuit. FIG. 17 is a diagram showing an example of the flow of processing executed by the aerosol generation device according to the present embodiment. FIG. 18 is a diagram for explaining issues related to the impedance circuit. FIG. 19 is a diagram showing an example of the configuration of an impedance circuit according to a modified example. FIG. 19 is a diagram showing an example of the configuration of an impedance circuit according to a modified example. FIG. 19 is a time chart for explaining intermittent operation by an amplifier. FIG. 19 is a graph showing experimental results when an amplifier is operated intermittently with a clock unit arranged between a pair of electrodes. 10 is a graph showing the experimental results when an amplifier is operated intermittently with a hand placed close to a pair of electrodes without a marking between them.

[0022] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0023] 1. Configuration Example of Aerosol Generating Device The aerosol generating device is a device that generates an aerosol to be inhaled by a user.

[0024] 1 is a schematic diagram showing an example of the configuration of an aerosol generating device. As shown in FIG. 1, the aerosol generating device 100 according to this example configuration includes a power supply unit 111, a sensor unit 112, a notification unit 113, a storage unit 114, a communication unit 115, a control unit 116, a heating unit 121, a storage unit 140, and a heat insulating unit 144.

[0025] The power supply unit 111 stores electric power. Then, the power supply unit 111 supplies electric power to each component of the aerosol generating device 100 based on the control of the control unit 116. The power supply unit 111 can be configured, for example, by a rechargeable battery such as a lithium ion secondary battery.

[0026] The sensor unit 112 acquires various information related to the aerosol generating device 100. As an example, the sensor unit 112 is configured with a pressure sensor such as a condenser microphone, a flow rate sensor, a temperature sensor, or the like, and acquires values ​​associated with inhalation by the user. As another example, the sensor unit 112 is configured with an input device such as a button or a switch that accepts information input from the user.

[0027] The notification unit 113 notifies the user of information. The notification unit 113 is configured by, for example, a light emitting device that emits light, a display device that displays an image, a sound output device that outputs sound, or a vibration device that vibrates.

[0028] The storage unit 114 stores various types of information for the operation of the aerosol generating device 100. The storage unit 114 is configured by a non-volatile storage medium such as a flash memory.

[0029] The communication unit 115 is a communication interface capable of performing communication conforming to any wired or wireless communication standard, such as Wi-Fi (registered trademark), Bluetooth (registered trademark), BLE (Bluetooth Low Energy (registered trademark)), NFC (Near Field Communication), or LPWA (Low Power Wide Area).

[0030] The control unit 116 functions as an arithmetic processing unit and a control unit, and controls the overall operation of the aerosol generation device 100 in accordance with various programs. The control unit 116 is realized by an electronic circuit such as a CPU (Central Processing Unit) or a microprocessor.

[0031] The storage unit 140 has an internal space 141 and holds the stick-shaped substrate 150 while accommodating a portion of the stick-shaped substrate 150 in the internal space 141. The storage unit 140 has an opening 142 that connects the internal space 141 to the outside and accommodates the stick-shaped substrate 150 inserted into the internal space 141 through the opening 142. For example, the storage unit 140 is a cylindrical body with the opening 142 and a bottom 143 as its bottom surface, and defines a columnar internal space 141. An air flow path that supplies air to the internal space 141 is connected to the storage unit 140. An air inlet, which is an air inlet to the air flow path, is arranged, for example, on a side surface of the aerosol generation device 100. An air outlet, which is an air outlet from the air flow path to the internal space 141, is arranged, for example, on the bottom 143.

[0032] The stick-shaped substrate 150 includes a substrate portion 151 and a mouthpiece portion 152. The substrate portion 151 includes an aerosol source. The aerosol source includes a tobacco-derived or non-tobacco-derived flavor component. When the aerosol generating device 100 is a medical inhaler such as a nebulizer, the aerosol source may include a medicament. The aerosol source may be, for example, a liquid such as a polyhydric alcohol, such as glycerin or propylene glycol, or water, containing a tobacco-derived or non-tobacco-derived flavor component, or a solid containing a tobacco-derived or non-tobacco-derived flavor component. When the stick-shaped substrate 150 is held in the storage portion 140, at least a portion of the substrate portion 151 is housed in the internal space 141, and at least a portion of the mouthpiece portion 152 protrudes from the opening 142. When a user holds the mouthpiece portion 152 protruding from the opening 142 in their mouth and inhales, air flows into the internal space 141 via an air flow path (not shown) and reaches the user's mouth along with the aerosol generated from the substrate portion 151.

[0033] The heating unit 121 generates aerosol by heating the aerosol source and atomizing the aerosol source. In the example shown in FIG. 1 , the heating unit 121 is configured in a film shape and is arranged to cover the outer periphery of the storage unit 140. When the heating unit 121 generates heat, the substrate unit 151 of the stick-shaped substrate 150 is heated from the outer periphery, generating aerosol. The heating unit 121 generates heat when power is supplied from the power supply unit 111. As an example, power may be supplied when the sensor unit 112 detects that the user has started inhaling and / or that predetermined information has been input. Power supply may be stopped when the sensor unit 112 detects that the user has stopped inhaling and / or that predetermined information has been input.

[0034] The heat insulating section 144 prevents heat transfer from the heating section 121 to other components. For example, the heat insulating section 144 is made of a vacuum heat insulating material, an aerogel heat insulating material, or the like.

[0035] The above describes an example of the configuration of the aerosol generation device 100. Of course, the configuration of the aerosol generation device 100 is not limited to the above, and various configurations such as those exemplified below may be used.

[0036] As one example, the heating unit 121 may be configured in a blade shape and disposed so as to protrude from the bottom 143 of the storage unit 140 into the internal space 141. In this case, the blade-shaped heating unit 121 is inserted into the substrate 151 of the stick-shaped substrate 150 and heats the substrate 151 of the stick-shaped substrate 150 from the inside. As another example, the heating unit 121 may be disposed so as to cover the bottom 143 of the storage unit 140. Furthermore, the heating unit 121 may be configured as a combination of two or more of a first heating unit covering the outer periphery of the storage unit 140, a blade-shaped second heating unit, and a third heating unit covering the bottom 143 of the storage unit 140.

[0037] As another example, the storage unit 140 may include an opening / closing mechanism such as a hinge that opens and closes a portion of the outer shell that forms the internal space 141. The storage unit 140 may then open and close the outer shell to hold and store the stick-shaped substrate 150 inserted into the internal space 141. In this case, the heating unit 121 may be provided at the holding location in the storage unit 140, and may heat the stick-shaped substrate 150 while pressing it.

[0038] Furthermore, the means for atomizing the aerosol source is not limited to heating by the heating unit 121. For example, the means for atomizing the aerosol source may be induction heating. In that case, the aerosol generation device 100 has at least an electromagnetic induction source such as a coil that generates a magnetic field, instead of the heating unit 121. A susceptor that generates heat by induction heating may be provided in the aerosol generation device 100, or may be included in the stick-shaped substrate 150.

[0039] 2. Technical Features 2.1. Overview An overview of the aerosol generating device 100 according to this embodiment will be described below with reference to FIG.

[0040] Fig. 2 is a diagram illustrating an overview of the aerosol generating device 100 according to this embodiment. Fig. 2 shows how the stick-shaped substrate 150 is inserted into the storage unit 140. As shown in Fig. 2, the direction in which the stick-shaped substrate 150 is inserted is also referred to as "downward," and the direction in which it is removed is also referred to as "upward."

[0041] The housing part 140 has an opening 142 on the upper side through which the stick-shaped substrate 150 can be inserted and removed in the vertical direction, and houses the stick-shaped substrate 150 in an internal space 141 .

[0042] The heating section 121 is disposed on the bottom 143 side of the housing section 140 and heats the stick-shaped substrate 150 housed in the housing section 140 .

[0043] The portion of stick-shaped substrate 150 where the aerosol source is distributed is also referred to as notched portion 153. Notched portion 153 is at least a part of substrate portion 151 shown in Fig. 1. Heating portion 121 and notched portion 153 are positioned so as to be thermally close to each other when housed in housing portion 140.

[0044] The aerosol generating device 100 includes a pair of electrodes C arranged to sandwich the internal space 141 and detecting the capacitance of the internal space 141 of the storage section 140 .

[0045] The aerosol generating device 100 includes a control circuit 10 that controls the operation of the aerosol generating device 100. The control circuit 10 corresponds to at least the control unit 116 among the components shown in FIG. 1. The control circuit 10 is connected to a pair of electrodes C, and detects insertion of the stick-shaped substrate 150 into the storage unit 140 based on the capacitance detected by the pair of electrodes C. The control circuit 10 is also connected to a heating unit 121, and controls the operation of the heating unit 121. For convenience, the control circuit 10, the pair of electrodes C, and the heating unit 121 are illustrated separately in FIG. 2, but hereinafter, it is assumed that the control circuit 10 includes the pair of electrodes C and the heating unit 121.

[0046] The control circuit 10 may have an auto-start function, i.e., the control circuit 10 may start heating by the heating unit 121 when it determines, based on the capacitance detected by the pair of electrodes C, that the stick-shaped substrate 150 has been inserted into the housing unit 140.

[0047] Here, the pair of electrodes C is disposed above the heating unit 121. In particular, the pair of electrodes C is disposed above the notched portion 153 when the stick-shaped substrate 150 is housed in the housing unit 140 (i.e., when the tip of the stick-shaped substrate 150 reaches the bottom portion 143 and insertion is complete). Therefore, the notched portion 153 passes through the pair of electrodes C (more precisely, the space between the pair of electrodes C) while the stick-shaped substrate 150 is being inserted into the housing unit 140. Here, the notched portion 153 has a higher dielectric constant than other portions of the stick-shaped substrate 150 where the aerosol source is not distributed, because the notched portion 153 has a distributed aerosol source. Therefore, when the notched portion 153 passes through the pair of electrodes C, the capacitance changes significantly between the period when the notched portion 153 is present between the pair of electrodes C and the period when the notched portion 153 is not present. Therefore, according to this embodiment, it is possible to accurately detect the insertion of the stick-shaped substrate 150 based on this change in capacitance.

[0048] The control circuit 10 determines whether the mark 153 is present between the pair of electrodes C, i.e., whether the stick-shaped substrate 150 has been inserted, based on the capacitance during a period T (hereinafter also referred to as the determination period) during which the amount of the mark 153 (i.e., the aerosol source) present between the pair of electrodes C is at its maximum. The determination period T is calculated using the vertical length Le [mm] of the pair of electrodes C, the vertical length Lk [mm] of the mark 153, and the insertion speed V [mm / s] of the stick-shaped substrate 150 into the storage section 140 according to the following equation:

[0049]

[0050] Hereinafter, for ease of explanation, a state in which the amount of the notches 153 present between a pair of electrodes C is maximum will also be referred to as "the notches 153 are present between the pair of electrodes C." On the other hand, a state in which the amount of the notches 153 present between the pair of electrodes C is not maximum will also be referred to as "the notches 153 are not present between the pair of electrodes C."

[0051] The outline of the aerosol generating device 100 according to this embodiment has been described above.

[0052] Various other techniques have been proposed for detecting the insertion of a stick, such as the stick-shaped substrate 150, into a device, such as the aerosol generating device 100.

[0053] For example, with regard to induction heating devices, a technology has been proposed that detects the insertion of a stick incorporating a susceptor into the device based on a change in inductance when the stick is inserted. However, if the stick incorporates a susceptor, there is a possibility that the susceptor may damage the digestive system if the stick is accidentally swallowed. Furthermore, such a technology can only be used with induction heating devices, and it has been difficult to apply it to heating devices such as the aerosol generating device 100.

[0054] In this regard, the technology according to the present embodiment described above does not require a built-in susceptor in the stick and is applicable to both induction-heated and heated devices, thereby improving the quality of the user experience.

[0055] Furthermore, a technology for detecting stick insertion based on capacitance has already been proposed, as in Patent Document 1. However, existing technologies, including Patent Document 1, detect the stick based on capacitance after the stick has been inserted. Specifically, even in existing technologies, the aerosol source is distributed in a position close to the heater or induction coil after the stick has been inserted. However, the sensor for measuring capacitance is often positioned away from the heater or induction coil to prevent noise from being mixed in from the heater or induction coil. Therefore, after the stick has been inserted, the area where the aerosol source is distributed is separated from the sensor, limiting the accuracy of stick insertion detection. Furthermore, even if it were possible to place the sensor for measuring capacitance outside the heater or induction coil, there would be concerns about noise mixing and an increase in the size of the device.

[0056] In this regard, the technology according to the present embodiment described above can accurately detect the insertion of the stick-shaped substrate 150 by referring to the change in capacitance when the notched portion 153, which has a high dielectric constant, passes through the pair of electrodes C. Furthermore, since the insertion of the stick-shaped substrate 150 can be detected during insertion rather than after insertion is complete, the auto-start function can be executed more quickly. Furthermore, since the pair of electrodes C can be positioned away from the heating unit 121, restrictions on sensor placement are relaxed, making it possible to further miniaturize the aerosol generation device 100. In this way, the quality of the user experience can be improved.

[0057] 3 is a diagram showing an example of the configuration of the control circuit 10. As shown in Fig. 3, the control circuit 10 includes a signal generator 11, an impedance circuit 12, a comparator 13, and a heating circuit 14.

[0058] The signal generator 11 generates a signal (hereinafter also referred to as an input signal) to be input to the impedance circuit 12. For example, the signal generator 11 generates one sine wave as the input signal.

[0059] The impedance circuit 12 is an AC circuit including a pair of electrodes C. An input signal generated by a signal generator 11 is input to the impedance circuit 12, and the impedance circuit 12 outputs an output signal. The relationship between the voltage Vin of the input signal to the impedance circuit 12 (hereinafter also referred to as the input voltage) and the voltage Vout of the output signal from the impedance circuit 12 (hereinafter also referred to as the output voltage) differs depending on whether or not there is a clock 153 between the pair of electrodes C. This is because the capacitance of the pair of electrodes C changes depending on whether or not there is a clock 153 between the pair of electrodes C, and the gain characteristics of the impedance circuit 12 change.

[0060] The comparator 13 compares the voltage Vout of the output signal from the impedance circuit 12 with the threshold voltage Vth and outputs the comparison result. The threshold voltage Vth is set to a value that allows the voltage Vout of the output signal from the impedance circuit 12 to be distinguished between a case where the clock portion 153 is present and a case where it is not present between the pair of electrodes C. Therefore, the comparator 13 outputs information indicating whether or not the clock portion 153 is present between the pair of electrodes C as the comparison result.

[0061] The heating circuit 14 controls the operation of the heating unit 121 based on the output from the comparator 13. The heating circuit 14 may be regarded as the control unit 116.

[0062] In particular, when the output from the comparator 13 satisfies a predetermined condition, the heating circuit 14 starts heating by the heating unit 121. More specifically, when the heating circuit 14 obtains a comparison result indicating that the notched portion 153 is present between the pair of electrodes C, it determines that the stick-shaped substrate 150 has been inserted and starts heating by the heating unit 121. On the other hand, the heating circuit 14 determines that the stick-shaped substrate 150 has not been inserted and waits for heating by the heating unit 121 to begin until it obtains a comparison result indicating that the notched portion 153 is present between the pair of electrodes C.

[0063] 2.3. Specific Examples The impedance circuit 12 may be a filter circuit. Specific examples in which the impedance circuit 12 is configured as an RC high-pass filter circuit or an RC low-pass filter circuit will be described below with reference to FIGS.

[0064] (RC High-Pass Filter) Fig. 4 is a diagram schematically illustrating an example of the configuration of the impedance circuit 12. As shown in Fig. 4, the impedance circuit 12a may be configured as an RC high-pass filter circuit having a pair of electrodes C and a resistor R.

[0065] The relationship between the input voltage Vin and the output voltage Vout of the impedance circuit 12a shown in FIG.

[0066]

[0067] C is the capacitance of the pair of electrodes C. R is the resistance value of resistor R. f is the frequency of the input signal.

[0068] The gain |G(jω)| for each frequency is calculated by the following equation.

[0069]

[0070] The cutoff frequency fc is calculated by the following formula:

[0071]

[0072] For example, the parameters of the impedance circuit 12a are set as follows: Resistance value R: 510 kΩ; Capacitance C: With the notched portion 153 between the pair of electrodes C: 6.7 pF; Without the notched portion 153 between the pair of electrodes C: 5.1 pF; Input signal frequency f: 5 kHz; Input signal amplitude: 1 Vp-p.

[0073] The gain characteristics of the impedance circuit 12a in the above parameter settings are shown in Figure 5. Figure 5 is a graph showing an example of the gain characteristics of the impedance circuit 12a shown in Figure 4. The vertical axis of this graph represents gain [dB], and the horizontal axis represents frequency [Hz]. The graph also shows the frequency characteristics of the gain of the output signal when the timed portion 153 is present and when it is not present between the pair of electrodes C. Referring to this graph, it can be seen that when the frequency f of the input signal is 5 [kHz] as shown in the above parameter settings, the gain of the output signal when the timed portion 153 is present between the pair of electrodes C is higher than the gain of the output signal when the timed portion 153 is not present between the pair of electrodes C.

[0074] The amplitude of the output signal of the impedance circuit 12a with the above parameter settings is as follows: With the mark 153 between the pair of electrodes C: 0.73 [Vp-p] Without the mark 153 between the pair of electrodes C: 0.63 [Vp-p]

[0075] Thus, there is a difference of 0.1 [V] in the amplitude of the output signal between when the marking 153 is present and when it is not present between the pair of electrodes C. In this case, the threshold voltage Vth can be set to 0.68 [V]. That is, when the output voltage Vout is equal to or greater than the threshold voltage Vth of 0.68 [V], the heating circuit 14 determines that the marking 153 is present between the pair of electrodes C. On the other hand, when the output voltage Vout is less than the threshold voltage Vth of 0.68 [V], the heating circuit 14 determines that the marking 153 is not present between the pair of electrodes C.

[0076] Here, the frequency f of the input signal is set based on the vertical length Le of the pair of electrodes C and the vertical length Lk of the notch 153. With this configuration, as will be described below, it becomes possible to accurately detect changes in capacitance that accompany the insertion of the stick-shaped substrate 150.

[0077] Specifically, the signal generator 11 sets the frequency f of the input signal so that one or more periods are included in the determination period T during which the amount of aerosol source present between the pair of electrodes C (i.e., the amount of the notched portion 153) is at its maximum, as calculated based on the vertical length Le of the pair of electrodes C, the vertical length Lk of the notched portion 153, and the assumed insertion speed V of the stick-shaped substrate 150. With this configuration, during the determination period T during which the amount of aerosol source present between the pair of electrodes C (i.e., the amount of the notched portion 153) remains unchanged, a change in the output voltage Vout due to a change in capacitance accompanying the insertion of the stick-shaped substrate 150 appears. This point will be explained with reference to FIG. 6 .

[0078] FIG. 6 is a graph showing an example of the time series change in the output voltage Vout associated with the insertion of the stick-shaped substrate 150. The vertical axis of this graph represents voltage, and the horizontal axis represents time, with time progressing from left to right. As shown in FIG. 6 , the insertion of the stick-shaped substrate 150 into the housing portion 140 progresses in the following order: insertion in progress (there is no clockwise portion 153 between the pair of electrodes C), insertion in progress (the clockwise portion 153 is present between the pair of electrodes C), and insertion complete. By setting the frequency f of the input signal as described above, as shown in FIG. 6 , there will be at least one opportunity during the determination period T for the output voltage Vout to be equal to or greater than the threshold voltage Vth. Therefore, the comparator 13 can reliably detect the presence of the clockwise portion 153 between the pair of electrodes C.

[0079] A specific example of the determination period T calculated based on the vertical length Le of the pair of electrodes C, the vertical length Lk of the notched portion 153, the expected insertion speed V of the stick-shaped substrate 150, and the above-mentioned formula 1 is shown below: Le: 5 [mm] Lk: 20 [mm] V: 75 [m / s] T: 2 [ms]

[0080] In the above parameter settings, the insertion speed V of the stick-shaped substrate 150 is assumed to be 75 m / s, which is the speed of a finger when snapping, and is considered to be the fastest speed in the human body. By adopting this speed, it is possible to assume the shortest determination period T. In other words, no matter how quickly the user inserts the stick-shaped substrate 150, the comparator 13 can detect the insertion of the stick-shaped substrate 150.

[0081] If the input signal is a sine wave, it is desirable that there be at least one peak of the sine wave (i.e., one or more cycles) during the determination period T. That is, it is desirable that the frequency f≧1 / T [Hz]. It is even more desirable that there be multiple peaks of the sine wave (e.g., 10 or more) during the determination period T, and for example, it is desirable that the frequency f≧10 / T [Hz].

[0082] In the above parameter settings, since T=0.002 [s], it is desirable to set the frequency f≧10 / T=5 [kHz].

[0083] The impedance circuit 12a is designed so that the cutoff frequency fc when the amount of the aerosol source present between the pair of electrodes C (i.e., the amount of the markings 153) is at its maximum corresponds to the frequency f of the input signal. For example, if the frequency f of the input signal is 5 kHz, the capacitance C of the pair of electrodes C and the resistance value R of the resistor R are set so that the cutoff frequency fc when the amount of the aerosol source present between the pair of electrodes C (i.e., the amount of the markings 153) is at its maximum is 5 kHz or higher. This configuration makes it possible to improve the detection accuracy of the markings 153.

[0084] (RC Low-Pass Filter) Fig. 7 is a diagram schematically illustrating another example of the configuration of the impedance circuit 12. As shown in Fig. 7, the impedance circuit 12b may be configured as an RC low-pass filter circuit having a pair of electrodes C and a resistor R.

[0085] The relationship between the input voltage Vin and the output voltage Vout of the impedance circuit 12b shown in FIG.

[0086]

[0087] C is the capacitance of the pair of electrodes C. R is the resistance value of resistor R. f is the frequency of the input signal.

[0088] The gain |G(jω)| for each frequency is calculated by the following equation.

[0089]

[0090] The cutoff frequency fc is calculated by the following formula:

[0091]

[0092] For example, the parameters of the impedance circuit 12b are set as follows: Resistance value R: 510 kΩ; Capacitance C: With the notched portion 153 between the pair of electrodes C: 6.7 pF; Without the notched portion 153 between the pair of electrodes C: 5.1 pF; Frequency f of the input signal: 5 kHz; Amplitude of the input signal: 1 Vp-p.

[0093] The gain characteristics of the impedance circuit 12b in the above parameter settings are shown in Figure 8. Figure 8 is a graph showing an example of the gain characteristics of the impedance circuit 12b shown in Figure 7. The vertical axis of this graph represents gain [dB], and the horizontal axis represents frequency [Hz]. The graph also shows the frequency characteristics of the gain of the output signal when the timed portion 153 is present and when it is not present between the pair of electrodes C. Referring to this graph, it can be seen that when the frequency f of the input signal is 5 [kHz] as shown in the above parameter settings, the gain of the output signal when the timed portion 153 is present between the pair of electrodes C is lower than the gain of the output signal when the timed portion 153 is not present between the pair of electrodes C.

[0094] The amplitude of the output signal of the impedance circuit 12b with the above parameter settings is as follows: With the marking 153 between the pair of electrodes C: 0.68 [Vp-p] Without the marking 153 between the pair of electrodes C: 0.77 [Vp-p]

[0095] Thus, there is a difference of approximately 0.1 [V] in the amplitude of the output signal between when the marking 153 is present and when it is not present between the pair of electrodes C. In this case, the threshold voltage Vth can be set to 0.73 [V]. That is, when the output voltage Vout is less than the threshold voltage Vth of 0.73 [V], the heating circuit 14 determines that the marking 153 is present between the pair of electrodes C. On the other hand, when the output voltage Vout is equal to or greater than the threshold voltage Vth of 0.73 [V], the heating circuit 14 determines that the marking 153 is not present between the pair of electrodes C.

[0096] The frequency f of the input signal may be set as described above for the RC high-pass filter. Similarly, the cutoff frequency fc during the determination period T, during which the amount of the aerosol source present between the pair of electrodes C (i.e., the amount of the notched portion 153) is at its maximum, may also be set as described above for the RC high-pass filter.

[0097] (Circuit Using Operational Amplifier) ​​The impedance circuit 12 may further include an amplifier for amplifying the output signal. An example of the circuit configuration in this case is shown in FIGS.

[0098] Fig. 9 is a diagram schematically illustrating another example of the configuration of the impedance circuit 12. As shown in Fig. 9, the impedance circuit 12c may be a high-pass filter circuit including an operational amplifier OA, an amplifier circuit 15 including resistors R1 and R2, and a pair of electrodes C. When the resistance value of the resistor R1 is equal to the resistance value of the resistor R2, the impedance circuit 12c shown in Fig. 9 is equivalent to the impedance circuit 12a configured as an RC high-pass filter circuit shown in Fig. 4.

[0099] Fig. 10 is a diagram schematically illustrating another example of the configuration of the impedance circuit 12. As shown in Fig. 10, the impedance circuit 12d may be a low-pass filter circuit including an operational amplifier OA, an amplifier circuit 15 including resistors R1 and R2, and a pair of electrodes C. When the resistance value of the resistor R1 is equal to the resistance value of the resistor R2, the impedance circuit 12d shown in Fig. 10 is equivalent to the impedance circuit 12b configured as an RC low-pass filter circuit shown in Fig. 7.

[0100] According to these circuit configurations, the output voltage Vout is amplified, and therefore the detection accuracy of the timer 153 can be improved.

[0101] 2.4. Processing Flow Next, an example of the processing flow for detecting the insertion of the stick-shaped substrate 150 will be described with reference to FIG.

[0102] FIG. 11 is a diagram showing an example of the flow of processing executed by the aerosol generating device 100 according to this embodiment.

[0103] 11 , first, the signal generator 11 starts supplying a signal to the impedance circuit 12 (step S102). For example, the signal generator 11 generates a sine wave as an input signal and supplies it to the impedance circuit 12. As a result, the impedance circuit 12 outputs the output voltage Vout, and the comparator 13 outputs the comparison result between the output voltage Vout and the threshold voltage Vth to the heating circuit 14.

[0104] Next, the heating circuit 14 determines whether the output from the comparator 13 satisfies a predetermined condition (step S104). As an example, for the impedance circuit 12a configured as an RC high-pass filter shown in Figure 4, the heating circuit 14 determines that the predetermined condition is that the output voltage Vout is equal to or greater than the threshold voltage Vth. As another example, for the impedance circuit 12b configured as an RC low-pass filter shown in Figure 7, the heating circuit 14 determines that the predetermined condition is that the output voltage Vout is less than the threshold voltage Vth.

[0105] If it is determined that the output from the comparator 13 does not satisfy the predetermined condition (step S104: NO), the heating circuit 14 determines that the notched portion 153 is not present between the pair of electrodes C, i.e., that the stick-shaped substrate 150 is not inserted (step S106).The heating circuit 14 then waits until the output from the comparator 13 satisfies the predetermined condition.

[0106] On the other hand, if it is determined that the output from the comparator 13 satisfies the predetermined condition (step S104: YES), the heating circuit 14 determines that the notched portion 153 is present between the pair of electrodes C, i.e., that the stick-shaped substrate 150 has been inserted (step S108).Then, the heating circuit 14 starts heating by the heating portion 121 (step S110).

[0107] 12 is a diagram for explaining a problem related to the impedance circuit 12. In FIG. 12, as an example, a problem related to the impedance circuit 12b configured as the RC low-pass filter shown in FIG. 7 is illustrated.

[0108] A first issue with the impedance circuit 12b is a reduction in the accuracy of detecting the insertion of the stick-shaped substrate 150 due to the electrostatic capacitance Human of the human body. As shown in FIG. 12 , in the impedance circuit 12b, the electrostatic capacitance Human that the human body has with GND forms a capacitance in parallel with the pair of electrodes C. Therefore, when the user's fingers approach the pair of electrodes C, such as when inserting the stick-shaped substrate 150 into the housing portion 140, the electrostatic capacitance Human of the human body increases the capacitance of the pair of electrodes C with respect to GND. As a result, there is a risk that the accuracy of detecting the insertion of the stick-shaped substrate 150 will decrease.

[0109] A second issue with the impedance circuit 12b is a reduction in the accuracy of detecting the insertion of the stick-shaped substrate 150 due to the parasitic capacitance Cline between the wires of the pair of electrodes C. As shown in Fig. 12, in the impedance circuit 12b, the parasitic capacitance Cline between the wires is a capacitance in parallel with the pair of electrodes C. Therefore, when the parasitic capacitance Cline between the wires is large, it becomes difficult to see a difference in the capacitance measured by the pair of electrodes C between when the notch 153 is present between the pair of electrodes C. As a result, the accuracy of detecting the insertion of the stick-shaped substrate 150 can be reduced.

[0110] If the accuracy of detecting the insertion of the stick-shaped substrate 150 decreases, there is a possibility that malfunctions may occur, such as auto-starting before insertion or not auto-starting after insertion.

[0111] A modified example that solves these problems will be described below with reference to Fig. 13. Fig. 13 is a diagram schematically illustrating an example of the configuration of an impedance circuit 12 according to the modified example.

[0112] As shown in FIG. 13 , the impedance circuit 12e may be configured with a resistor R connected in parallel to the input signal and a pair of electrodes C connected in series to the input signal. In other words, the signal generator 11, the pair of electrodes C, and the comparator 13 may form part of a series circuit. With this configuration, the electrostatic capacitance of the human body, Human, does not become a capacitance in parallel with the pair of electrodes C. Therefore, it is possible to suppress an increase in the capacitance of the pair of electrodes C to GND caused by the electrostatic capacitance of the human body, Human. As a result, it is possible to prevent a decrease in the detection accuracy of the insertion of the stick-shaped substrate 150. In this way, the first problem described above is solved.

[0113] 13, in the impedance circuit 12e, the wiring between the pair of electrodes C is shielded at GND potential. More specifically, the wiring between the pair of electrodes C and a circuit for detecting the capacitance of the pair of electrodes C (e.g., comparator 13) is shielded at GND potential. This prevents the parasitic capacitance Cline between the electrodes C from becoming a capacitance in parallel with the pair of electrodes C. Therefore, even when the parasitic capacitance Cline between the electrodes C is large, a clear difference can be made in the capacitance measured by the pair of electrodes C between when the notched portion 153 is present and when it is not present. As a result, it is possible to prevent a decrease in the detection accuracy of the insertion of the stick-shaped substrate 150. In this way, the second problem described above is solved.

[0114] The first problem described above can also be solved by the impedance circuit 12a configured as an RC high-pass filter circuit shown in Fig. 4. This is because, in the impedance circuit 12a as well, the signal generator 11, the pair of electrodes C, and the comparator 13 form part of a series circuit.

[0115] <3.2. Modified Example of Circuit Using Amplifier> A modified example of the impedance circuit 12 including an amplifier that amplifies the output signal will be described below with reference to Fig. 14. Fig. 14 is a diagram schematically illustrating an example of the configuration of the impedance circuit 12 according to the modified example.

[0116] 14, the impedance circuit 12f may be configured with a pair of electrodes C connected in series with an input signal, a first amplifier circuit 15-1, a capacitor C', and a second amplifier circuit 15-2. The first amplifier circuit 15-1 is configured with resistors R1 and R2 and an operational amplifier OA1. The second amplifier circuit 15-2 is configured with resistors R3 and R4 and an operational amplifier OA2.

[0117] The impedance Z of the impedance circuit 12f shown in FIG. 14 when there is no notched portion 153 between the pair of electrodes C is calculated by the following equation.

[0118]

[0119] On the other hand, when the notch 153 is present between the pair of electrodes C, the impedance Z is calculated by the following formula.

[0120]

[0121] Here, ΔC is the capacitance of the notch 153 present between the pair of electrodes C.

[0122] The relationship between the input voltage Vin and the output voltage Vout is expressed by the following equation:

[0123]

[0124] Here, R1 to R4 are the resistance values ​​of the resistors R1 to R4.

[0125] The gain |G(jω)| for each frequency is calculated by the following equation.

[0126]

[0127] An ideal operational amplifier can amplify frequencies up to infinity, but in reality, there is a limit to the frequencies that an operational amplifier can amplify.

[0128] For example, the parameters of the impedance circuit 12f are set as follows: Frequency f of the input signal: 32.768 [kHz] Amplitude of the input signal: 5 [V] Impedance Z Without the notched portion 153 between the pair of electrodes C: 13.88 [MΩ] With the notched portion 153 between the pair of electrodes C: 9.17 [MΩ] Resistor R1: 51 [kΩ] Resistor R2: 330 [kΩ] Resistor R3: 5.1 [kΩ] Resistor R4: 82 [kΩ]

[0129] The amplitude of the output signal of the impedance circuit 12a with the above parameter settings is as follows: With the mark 153 between the pair of electrodes C: 3.5072 [Vp-p] Without the mark 153 between the pair of electrodes C: 3.9965 [Vp-p]

[0130] Thus, there is a difference of 0.49 [V] in the amplitude of the output signal between when the marking 153 is present and when it is not present between the pair of electrodes C. In this case, the threshold voltage Vth can be set to 3.75 [V]. That is, when the output voltage Vout is less than the threshold voltage Vth of 3.75 [V], the heating circuit 14 determines that the marking 153 is present between the pair of electrodes C. On the other hand, when the output voltage Vout is equal to or greater than the threshold voltage Vth of 3.75 [V], the heating circuit 14 determines that the marking 153 is not present between the pair of electrodes C.

[0131] In this way, compared to circuits without an amplifier such as the impedance circuits 12a and 12b, the impedance circuit 12f can amplify the difference in amplitude of the output signal between when the timing portion 153 is present and when it is not present between the pair of electrodes C. This makes it possible to improve the detection accuracy of the timing portion 153.

[0132] 3.3. Modifications Related to Intermittent Operation The control circuit 10 may intermittently detect the stick-shaped substrate 150. For example, in the impedance circuit 12 having an amplifier, the amplifier may operate intermittently. This configuration makes it possible to reduce power consumption.

[0133] In particular, the amplifier may operate intermittently at a cycle corresponding to the length of the determination period T. For example, the amplifier's ON / OFF cycle is set to be equal to or shorter than the determination period T. However, if the input signal is a sine wave, it is desirable to set the ON / OFF cycle so that the period in which the amplifier is ON includes at least one peak of the sine wave. With this configuration, it is possible to reduce power consumption while maintaining the detection accuracy of the clock unit 153.

[0134] Hereinafter, the intermittent operation of the amplifier circuits 15-1 and 15-2 (more specifically, the operational amplifiers OA1 and OA2) as amplifiers in the impedance circuit 12f shown in FIG. 14 will be described with reference to FIG.

[0135] FIG. 15 is a time chart for explaining the intermittent operation of the amplifier. The upper time chart shows the clock ON / OFF of the RTC (Real Time Clock) mounted on the control circuit 10. The middle time chart shows the ON / OFF of the amplifier (i.e., operational amplifiers OA1 and OA2). During the period when the amplifier is ON, an output voltage Vout corresponding to the presence or absence of the clock 153 between the pair of electrodes C is output from the impedance circuit 12f, making it possible to determine the presence or absence of the clock 153 between the pair of electrodes C. The lower time chart shows the time series transition of whether or not the clock 153 is present between the pair of electrodes C when the stick-shaped substrate 150 is inserted. That is, YES indicates that the clock 153 is present between the pair of electrodes C, and NO indicates that the clock 153 is not present between the pair of electrodes C.

[0136] As shown in Figure 15, operational amplifiers OA1 and OA2 are turned on / off in synchronization with the RTC clock. The operational amplifiers OA1 and OA2 are repeatedly turned on for 244 μs and off for 1.756 ms. In this case, the period of the operational amplifiers OA1 and OA2 is 2 ms, which coincides with the length of the target determination period T, 2 ms. With this configuration, the operational amplifiers OA1 and OA2 are turned on at least once during the target determination period T, making it possible to determine whether or not a clock 153 exists between a pair of electrodes C.

[0137] A specific example of parameter settings for the impedance circuit 12f is shown below: Current consumption when amplifier is ON: 1.2 [mA] Current consumption when amplifier is OFF: 1.1 [μA] Determination target period T: 2 [ms] Amplifier ON period: 244 [μs] Amplifier OFF period: 1.756 [ms]

[0138] With the above parameter settings, the total average current consumption I is calculated using the following formula:

[0139]

[0140] In this way, by operating the amplifier intermittently, it is possible to reduce current consumption compared to when the amplifier is always on. By adjusting the on / off duty ratio, it is possible to balance maintaining detection accuracy and reducing current consumption.

[0141] The experimental results of this modification will be described with reference to FIGS. 16 and 17. FIG.

[0142] 16 is a graph showing experimental results when the amplifier (i.e., operational amplifiers OA1 and OA2) was operated intermittently with the clock 153 disposed between a pair of electrodes C. The vertical axis of this graph represents voltage, and the horizontal axis represents time, with time flowing from left to right. Waveform 21 represents the waveform of the input signal. Waveform 22 represents the output from comparator 13. As shown in waveform 21, there are cyclical periods during which the amplifier is turned off and the input signal voltage Vin does not change, and periods during which the amplifier is turned on and the input signal voltage Vin changes. As shown in waveform 22, the output from comparator 13 changes during the period during which the amplifier is turned on. That is, comparator 13 outputs an indication that the clock 153 is present between the pair of electrodes C.

[0143] FIG. 17 is a graph showing experimental results when the amplifier (i.e., operational amplifiers OA1 and OA2) was operated intermittently with a hand placed close to a pair of electrodes C without the clock 153 between them. The vertical axis of this graph represents voltage, and the horizontal axis represents time, with time flowing from left to right. Waveform 21 represents the waveform of the input signal. Waveform 22 represents the output from comparator 13. As shown in waveform 21, there are cyclical periods during which the amplifier is turned off and the input signal voltage Vin does not change, and periods during which the amplifier is turned on and the input signal voltage Vin changes. Furthermore, as shown in waveform 22, the output from comparator 13 does not change even during the period during which the amplifier is turned on. In other words, comparator 13 outputs an indication that the clock 153 is not present between the pair of electrodes C.

[0144] <4. Supplementary Information> Although preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings, the present disclosure is not limited to such examples. It is clear that a person skilled in the art to which the present disclosure pertains can conceive of various modified or altered examples within the scope of the technical ideas described in the claims, and it is understood that these also naturally fall within the technical scope of the present disclosure.

[0145] The heating unit 121 described in the above embodiment is an example of a load that generates heat, which is energy for heating the aerosol source of the stick-shaped substrate 150 housed in the housing unit 140. The load is not limited to the heating unit 121. When the means for heating the aerosol source is induction heating, the load may be an induction coil that generates a magnetic field, which is energy for induction heating a susceptor that is thermally close to the aerosol source.

[0146] In the above embodiment, an example has been described in which the insertion speed V of the stick-shaped substrate 150 is assumed to be 75 m / s, which is the finger speed during a finger snap, and the frequency f of the input signal is set. However, the present disclosure is not limited to such an example. For example, the signal generator 11 may set the frequency f of the input signal based on the time during which the capacitance of the pair of electrodes C changes, measured when the user inserts the stick-shaped substrate 150 into the housing portion 140. Here, the time during which the capacitance of the pair of electrodes C changes refers to the time during which the amount of aerosol source present between the pair of electrodes C (i.e., the amount of the interval 153) is at its maximum. For example, the time during which it is determined that the interval 153 is present between the pair of electrodes C by comparing the output voltage Vout with the threshold voltage Vth when the aerosol generation device 100 is actually used may be used as this time.

[0147] In the above embodiment, an example has been described in which the vertical length Le of the pair of electrodes C is given, and the frequency f of the input signal is set based on the vertical length Le of the pair of electrodes C and the vertical length Lk of the markings 153. However, the present disclosure is not limited to such an example. At least one of the vertical length Le of the pair of electrodes C and the frequency f of the input signal may be set based on the vertical length Lk of the markings 153. As an example, when the frequency f of the input signal is given, the vertical length Le of the pair of electrodes C may be set based on the frequency f of the input signal and the vertical length Lk of the markings 153. In this case, the vertical length Le of the pair of electrodes C is set to a value that includes one or more periods determined from the frequency f of the input signal during the determination period T in which the amount of the aerosol source present between the pair of electrodes C (i.e., the amount of the markings 153) is at its maximum.

[0148] In the above embodiment, an example has been described in which the pair of electrodes C are positioned above the notched portions 153 when the insertion of the stick-shaped substrate 150 into the housing portion 140 is complete, but the present disclosure is not limited to such an example. The pair of electrodes C may be positioned so as to overlap with the notched portions 153 when the insertion of the stick-shaped substrate 150 into the housing portion 140 is complete.

[0149] In the above embodiment, an example has been described in which the auto-start function is executed using the detection of the insertion of the stick-shaped substrate 150 as a trigger, but the present disclosure is not limited to such an example. The detection of the insertion of the stick-shaped substrate 150 may also be used as a trigger to execute a wake-up function (return from a low-power standby mode).

[0150] Although the above describes an example in which the signal generator 11 generates a single sine wave, the present disclosure is not limited to such an example. As an example, the signal generator 11 may generate a single square wave. As another example, the signal generator 11 may generate a composite signal obtained by combining multiple signals as the input signal. In this case, it is sufficient that at least one of the one or more signals constituting the input signal has the technical features related to the input signal described above. For example, the signal generator 11 may set the frequency of at least one of the one or more signals constituting the input signal based on the vertical length Le of the pair of electrodes C and the vertical length Lk of the notched portion 153.

[0151] The series of processes performed by each device described herein may be implemented using software, hardware, or a combination of software and hardware. The software programs may be stored in advance, for example, on a recording medium (more specifically, a non-transitory computer-readable storage medium) internal or external to each device. Each program is then loaded into a random access memory (RAM) and executed by a processing circuit such as a central processing unit (CPU). The recording medium may be, for example, a magnetic disk, an optical disk, a magneto-optical disk, or a flash memory. The computer program may also be distributed, for example, via a network, without using a recording medium. The computer may be, for example, an application-specific integrated circuit (ASIC), a general-purpose processor that executes functions by loading a software program, or a computer on a server used in cloud computing. The series of processes performed by each device described herein may be centrally processed by a single computer or distributed across multiple computers. Furthermore, in each of the above embodiments, two or more communication means present in a single device may be physically implemented on a single medium.

[0152] Furthermore, the processes described herein using flowcharts or sequence diagrams do not necessarily have to be performed in the order shown. Some process steps may be performed in parallel. Furthermore, additional process steps may be employed, and some process steps may be omitted.

[0153] Note that the following configurations also fall within the technical scope of the present disclosure: (1) An aerosol generation device comprising: a storage unit having an opening on its upper side through which a substrate containing an aerosol source can be inserted and removed in the vertical direction and storing the substrate in an internal space; a load that generates energy for heating the aerosol source of the substrate stored in the storage unit; an impedance circuit including a pair of electrodes that detects the capacitance of the internal space of the storage unit; a signal generator that generates an input signal to be input to the impedance circuit; a comparator that compares the voltage of the output signal from the impedance circuit with a threshold voltage; and a control unit that controls the operation of the load based on the output from the comparator, wherein the pair of electrodes are disposed above the load, and at least one of the vertical lengths of the pair of electrodes and the frequency of at least one signal among the one or more signals that make up the input signal is set based on the vertical length of a portion of the substrate where the aerosol source is distributed, and the control unit starts the generation of energy by the load when the output from the comparator satisfies a predetermined condition. (2) The aerosol generating device according to (1), wherein the pair of electrodes is positioned above a portion of the substrate where an aerosol source is distributed when the substrate has been completely inserted into the storage unit. (3) The aerosol generating device according to (1) or (2), wherein the signal generator sets the frequency of at least one of the one or more signals constituting the input signal so that one or more periods are included in a determination period during which the amount of the aerosol source present between the pair of electrodes is at its maximum, the determination period being calculated based on the vertical length of the pair of electrodes, the vertical length of the portion of the substrate where an aerosol source is distributed, and an expected insertion speed of the substrate into the storage unit. (4) The aerosol generating device according to any one of (1) to (3), wherein the control unit sets the frequency of at least one of the one or more signals constituting the input signal based on a time during which the capacitance of the pair of electrodes is changing, measured when the user inserts the substrate into the storage unit. (5) The aerosol generating device according to any one of (1) to (4), wherein the impedance circuit is a filter circuit.(6) The aerosol generation device according to (5), wherein the filter circuit is designed so that a cutoff frequency when the amount of the aerosol source present between the pair of electrodes is at a maximum corresponds to the frequency of at least one signal among the one or more signals that constitute the input signal. (7) The aerosol generation device according to any one of (1) to (6), wherein the signal generator, the pair of electrodes, and the comparator constitute part of a series circuit. (8) The aerosol generation device according to any one of (1) to (7), wherein wiring between the pair of electrodes is shielded at GND potential. (9) The aerosol generation device according to any one of (1) to (8), wherein the impedance circuit further includes an amplifier that amplifies the output signal. (10) The aerosol generation device according to (9), wherein the amplifier operates intermittently. (11) The aerosol generating device according to (10), wherein the amplifier operates intermittently at a period corresponding to the length of a determination period during which the amount of the aerosol source present between the pair of electrodes is at its maximum, the period being calculated based on the vertical length of the pair of electrodes, the vertical length of a portion of the substrate in which the aerosol source is distributed, and an estimated insertion speed of the substrate into the storage section. (12) The aerosol generating device according to any one of (1) to (11), wherein the input signal is a single sine wave. (13) The aerosol generating device according to any one of (1) to (12), wherein the load is a heating section.

[0154] REFERENCE SIGNS LIST 100 Aerosol generating device 111 Power supply unit 112 Sensor unit 113 Notification unit 114 Memory unit 115 Communication unit 116 Control unit 121 Heating unit 140 Storage unit 141 Internal space 142 Opening 143 Bottom 144 Heat insulating unit 150 Stick-shaped substrate 151 Substrate unit 152 Suction nozzle unit 10 Control circuit 11 Signal generator 12 Impedance circuit 13 Comparator 14 Heating circuit 15 Amplification circuit

Claims

1. An aerosol generation device comprising: a storage unit having an opening on its upper side through which a substrate containing an aerosol source can be inserted and removed in the vertical direction, and storing the substrate in its internal space; a load that generates energy to heat the aerosol source of the substrate stored in the storage unit; an impedance circuit including a pair of electrodes that detects the capacitance of the internal space of the storage unit; a signal generator that generates an input signal to be input to the impedance circuit; a comparator that compares the voltage of the output signal from the impedance circuit with a threshold voltage; and a control unit that controls the operation of the load based on the output from the comparator, wherein the pair of electrodes are positioned above the load, and at least one of the vertical lengths of the pair of electrodes and the frequency of at least one signal among the one or more signals that make up the input signal is set based on the vertical length of a portion of the substrate where the aerosol source is distributed, and the control unit starts the generation of energy by the load when the output from the comparator satisfies a predetermined condition.

2. The aerosol generating device according to claim 1, wherein the pair of electrodes is positioned above a portion of the substrate where the aerosol source is distributed when the substrate has been completely inserted into the storage section.

3. The aerosol generating device described in claim 1 or 2, wherein the signal generator sets the frequency of at least one of the one or more signals constituting the input signal so that one or more periods are included in the determination period in which the amount of the aerosol source present between the pair of electrodes is at its maximum, calculated based on the vertical length of the pair of electrodes, the vertical length of the portion of the substrate in which the aerosol source is distributed, and the estimated insertion speed of the substrate into the storage section.

4. An aerosol generating device as described in any one of claims 1 to 3, wherein the control unit sets the frequency of at least one of the one or more signals constituting the input signal based on the time during which the capacitance of the pair of electrodes changes, measured when the user inserts the substrate into the storage unit.

5. The aerosol generating device according to any one of claims 1 to 4, wherein the impedance circuit is a filter circuit.

6. The aerosol generating device described in claim 5, wherein the filter circuit is designed so that the cutoff frequency when the amount of the aerosol source present between the pair of electrodes is maximum corresponds to the frequency of at least one of the one or more signals that constitute the input signal.

7. An aerosol generating device according to any one of claims 1 to 6, wherein the signal generator, the pair of electrodes, and the comparator form part of a series circuit.

8. The aerosol generating device according to any one of claims 1 to 7, wherein the wiring between the pair of electrodes is shielded at GND potential.

9. An aerosol generating device according to any one of claims 1 to 8, wherein the impedance circuit further comprises an amplifier that amplifies the output signal.

10. The aerosol generating device according to claim 9, wherein the amplifier operates intermittently.

11. The aerosol generating device described in claim 10, wherein the amplifier operates intermittently at a period corresponding to the length of a determination period during which the amount of the aerosol source present between the pair of electrodes is at its maximum, calculated based on the vertical length of the pair of electrodes, the vertical length of the portion of the substrate in which the aerosol source is distributed, and the estimated insertion speed of the substrate into the storage section.

12. The aerosol generating device according to any one of claims 1 to 11, wherein the input signal is a single sine wave.

13. The aerosol generating device according to any one of claims 1 to 12, wherein the load is a heating unit.

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