Power supply unit for aerosol generating device and control method thereof

Abstract

Provided is a highly safe aerosol generator. This power supply unit (110) comprises: an MCU (11) that controls the supply of heating power from a battery (12) to a heater (40); a protection circuit (30) that limits the supply of the heating power to the heater (40); and a monitoring circuit (20) that includes a charging circuit (a resistive element (22) and a capacitor (23)) capable of storing electricity by means of an output voltage Vs, when heating power is supplied from the battery (12) to the heater (40), and outputs a signal (abnormality detection signal) for operating the protection circuit (30) on the basis of the voltage of the charging circuit, wherein the MCU (11) performs discharge control to discharge the voltage of the charging circuit at a timing (a start timing of a measurement period TD) based on a supply period (control period TC) of the heating power to the heater (40).

Description

[Technical Field]

[0001] The present invention relates to a power supply unit for an aerosol generating device and a control method thereof. [Background technology]

[0002] Patent Document 1 discloses an aerosol generating system including a heating element for heating an aerosol-forming substrate, a power supply for supplying power to the heating element, and an electrical circuit in communication with the heating element and the power supply. The electrical circuit adjusts the power supply to the heating element during a plurality of individual heating cycles in response to user input, determines the maximum electrical resistance of the heating element during each heating cycle, calculates a moving average of the maximum electrical resistance of the heating element over n previous heating cycles, compares the electrical resistance of the heating element with the calculated moving average, determines a malfunction when the electrical resistance is greater than the moving average by more than a threshold value, and controls the power supplied to the heating element based on whether the heating element is malfunctioning.

[0003] Patent Document 2 describes an aerosol generating system including an electric heater having a heating element for heating an aerosol-forming substrate, a power supply, and an electric circuit connected to the electric heater and the power supply. The electric circuit determines a predetermined state when the ratio of the initial electric resistance of the electric heater to the change in the electric resistance from the initial electric resistance is greater than a maximum threshold, and limits the power supplied to the electric heater when the predetermined state is met. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japan Special Publication No. 2021-526015 [Patent Document 2] Japan Special Publication No. 2018-514191 Summary of the Invention [Problem to be solved by the invention]

[0005] As disclosed in Patent Documents 1 and 2, in an aerosol generating device, a processor that controls the power supply to a heating element for heating an aerosol-forming substrate is known to limit the power supply to the heating element when the temperature of the heating element or the temperature of the aerosol-forming substrate heated by the heating element is high, etc. However, if some abnormality occurs in the processor, it may not be possible to limit the power supply to the heating element.

[0006] An object of the present invention is to provide a power supply unit for an aerosol generating device with improved safety and a control method thereof. [Means for solving the problem]

[0007] The power supply unit of an aerosol generating device of one embodiment of the present invention comprises a power supply, a processor that controls the supply of heating power from the power supply to a heating element for heating an aerosol source and / or a flavor source, a protection circuit that limits the supply of the heating power to the heating element, and a monitoring circuit that includes a charge circuit that can be charged with the heating power when heating power is supplied from the power supply to the heating element, and outputs a signal to activate the protection circuit based on the voltage of the charge circuit, and the processor performs discharge control to discharge the voltage of the charge circuit at a timing based on the supply period of the heating power to the heating element.

[0008] One embodiment of the present invention provides a control method for a power supply unit of an aerosol generating device, which includes a processor that controls the supply of power from a power source to a heating element for heating an aerosol source and / or a flavor source, a protection circuit that limits the supply of the power to the heating element, and a charge circuit that can store power using the power, and which performs discharge control to discharge the voltage of the charge circuit at a timing based on the supply cycle of the power to the heating element, and activates the protection circuit based on the voltage of the charge circuit. [Effects of the Invention]

[0009] According to the present invention, safety can be improved. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of the configuration of an aerosol generating device. [Figure 2] 2 is a diagram showing a specific example of an electronic circuit 10 involved in heating a base portion in the power supply unit 110 shown in FIG. 1. FIG. [Figure 3] 10 is a timing chart for explaining the operation of the MCU 11 in the aerosol generation mode. [Figure 4] FIG. 2 is a diagram illustrating an example of a protection circuit 30. [Figure 5] FIG. 10 is a diagram showing an example of a heating profile. [Figure 6] 3 is a diagram showing an electronic circuit 10A which is a modified example of the electronic circuit 10 shown in FIG. 2. FIG. [Figure 7] 10 is a timing chart for explaining the operation of the MCU 11 in the second modified example. [Figure 8] 3 is a diagram showing an electronic circuit 10B which is a modified example of the electronic circuit 10 shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] The aerosol generating device of the embodiment is a device that consumes power to atomize an aerosol source contained in an attached aerosol forming body to generate an aerosol, and makes the generated aerosol inhalable. The aerosol generating device has a variety of configurations and is not particularly limited, but a typical configuration example of the aerosol generating device will be described below with reference to FIG.

[0012] Fig. 1 is a schematic diagram showing a configuration example of an aerosol-generating device. The aerosol-generating device 100A shown in Fig. 1 includes a power supply unit 110 including a power supply section 111A, a sensor section 112A, a notification section 113A, a storage section 114A, a communication section 115A, a control section 116A, a heating section 121A, a holding section 140, and a heat insulating section 144, and a stick-shaped substrate 150 that constitutes an aerosol-forming body.

[0013] The power supply unit 111A stores electric power. Then, the power supply unit 111A supplies electric power to each component of the aerosol generation device 100A based on the control of the control unit 116A. The power supply unit 111A can be configured by, for example, a rechargeable battery such as a lithium ion secondary battery.

[0014] The sensor unit 112A acquires various information related to the aerosol generation device 100A. As an example, the sensor unit 112A is configured with an suction sensor configured with a pressure sensor such as a condenser microphone, a flow rate sensor, or a temperature sensor, and acquires values ​​associated with inhalation by the user. As another example, the sensor unit 112A is configured with an input device such as a button or a switch that accepts information input from the user.

[0015] Notification unit 113A notifies the user of information. Notification unit 113A 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.

[0016] The storage unit 114A stores various types of information for the operation of the aerosol generation device 100 A. The storage unit 114A is configured by a nonvolatile storage medium such as a flash memory, for example.

[0017] The communication unit 115A is a communication interface capable of performing communication in accordance with any wired or wireless communication standard, such as Wi-Fi (registered trademark) or Bluetooth (registered trademark).

[0018] The control unit 116A controls the overall operation of the aerosol generation device 100A in accordance with various programs. The control unit 116A includes, for example, a CPU (Central Processing Unit). The ROM is realized by an electronic circuit including a processor such as a Micro Controller Unit (MCU) or an MCU.

[0019] The holding part 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 holding part 140 has an opening 142 that connects the internal space 141 to the outside, and holds the stick-shaped substrate 150 inserted into the internal space 141 through the opening 142. For example, the holding part 140 is a cylindrical body with the opening 142 and a bottom 143 as its bottom surface, and defines a columnar internal space 141. The holding part 140 also has the function of defining a flow path for air to be supplied to the stick-shaped substrate 150. An air inlet, which is an entrance for air to this flow path, is located in, for example, the bottom 143. On the other hand, an air outlet, which is an exit for air from this flow path, is the opening 142.

[0020] 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 is generated by atomizing the aerosol source. The aerosol source is, for example, a liquid such as a polyhydric alcohol, such as glycerin or propylene glycol, or water. In this configuration example, the aerosol source is not limited to a liquid, but may also be a solid. The substrate portion 151 may further include a flavor source. The flavor source is a component for imparting a flavor component to the aerosol. The flavor source includes a flavor component derived from tobacco or non-tobacco (derived from additives such as menthol or flavorings).

[0021] With stick-shaped substrate 150 held by holder 140, at least a portion of substrate 151 is housed in internal space 141, and at least a portion of suction mouth 152 protrudes from opening 142. When a user holds suction mouth 152 protruding from opening 142 in their mouth and inhales, air flows into internal space 141 through an air inlet hole (not shown) and reaches the user's mouth together with the aerosol generated from substrate 151.

[0022] 1, the heating unit 121A is a sheet-like heater and is arranged to cover the outer periphery of the holding unit 140. When the heating unit 121A generates heat, the substrate unit 151 of the stick-shaped substrate 150 is heated from the outer periphery, and an aerosol is generated. The sheet-like heater constitutes a heating element for heating the aerosol source contained in the substrate unit 151 (and further heating the flavor source if the substrate unit 151 contains a flavor source).

[0023] The heat insulating section 144 prevents heat transfer from the heating section 121A 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.

[0024] An example configuration of the aerosol generation device 100A has been described above. Of course, the configuration of the aerosol generation device 100A is not limited to the above, and various configurations such as those exemplified below may be used. As an example, the heating unit 121A may be configured with a blade-shaped heater and may be arranged so as to protrude from the bottom 143 of the holding unit 140 into the internal space 141. In this case, the heating unit 121A 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 sheet-shaped heater constituting the heating unit 121A may be arranged so as to cover the bottom 143 of the holding unit 140. Furthermore, the heating unit 121A may be configured as a combination of two or more of a first heating unit covering the outer periphery of the holding unit 140, a blade-shaped second heating unit, and a third heating unit covering the bottom 143 of the holding unit 140.

[0025] As another example, the holding 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 holding unit 140 may clamp the stick-shaped substrate 150 inserted into the internal space 141 by opening and closing the outer shell. In this case, the heating unit 121A may be provided at the clamping location of the holding unit 140 and heat the stick-shaped substrate 150 while pressing it. Furthermore, the means for heating the substrate 151 is not limited to direct heating by the heating unit 121A. For example, the substrate 151 may be heated by induction heating. When induction heating is employed, the heating unit 121A may be a reactor (coil), and a susceptor may be housed inside the substrate 151. With this configuration, the susceptor can be heated by induction heating when power is supplied to the reactor, thereby heating the substrate 151. In this case, the reactor constitutes a heating element.

[0026] Furthermore, the aerosol generating device 100A may be configured so that a container filled with an aerosol source and a flavor source, or only with an aerosol source, can be accommodated in the internal space 141 instead of the stick-shaped substrate 150, and the heating unit 121A may heat the container.

[0027] Furthermore, the aerosol generation device 100A may be configured such that a first container containing a liquid aerosol source and a heating unit (heater) for heating the aerosol source, and a second container containing a flavor source and capable of being placed in a path through which the aerosol generated by heating the aerosol source of the first container can pass, are detachably attached to the power supply unit 110, and the control unit 116A controls the power supply to the heating unit of the first container to generate a flavored aerosol. In this configuration, the power supply unit 110 may further be provided with a heating unit for heating the second container, and the control unit 116A may control the power supply to the heating unit for heating the second container to heat the flavor source.

[0028] (Example of power supply unit circuit configuration) FIG. 2 is a diagram showing a specific example of the electronic circuit 10 involved in heating the base portion 151 in the power supply unit 110 (hereinafter also simply referred to as the power supply unit) shown in FIG.

[0029] The electronic circuit 10 includes a battery 12, an example of a power supply unit 111A, an MCU 11, an example of a control unit 116A, an LDO (Low Drop Out) regulator 14, a suction sensor 15, an example of a sensor unit 112A, switches SW1a, SW1b, SW2, SW3, an operational amplifier 16, a resistor Rs, a comparator 17, a comparator 18, a comparator 21, a resistor 22, a capacitor 23, a resistor 24, and a switch SW4, and a monitoring circuit 20 including the switch SW4, and a protection circuit 30. The MCU 11 includes an analog-to-digital converter (hereinafter referred to as ADC) 50b and a memory 50a that stores various information. Hereinafter, the switch SW1a or the switch SW1b will be collectively referred to as switch SW1.

[0030] The resistive element described in this specification may be any element having a fixed electrical resistance, such as a resistor, a diode, or a transistor. In the example of Fig. 2, the resistive element Rs, the resistive element 22, and the resistive element 24 are each resistors. Also, in the example of Fig. 2, the heater 40 is a resistor.

[0031] The switch described in this specification is a semiconductor switching element such as a transistor that switches between interruption and conduction of a wiring path, or a load switch configured by combining a capacitor, a resistor, a transistor, etc. The state in which the switch conducts between the input and output is described as an on state, and the state in which the switch interrupts between the input and output is described as an off state.

[0032] An input terminal of an LDO regulator 14 and one end of a switch SW1a are connected to a main positive bus LU connected to the positive electrode of the battery 12. The LDO regulator 14 steps down and outputs the voltage from the battery 12. The output voltage Vs of the LDO regulator 14 is also used as an operating voltage for each of the MCU 11, the operational amplifier 16, the comparators 17 and 18, and the comparator 21 of the monitoring circuit 20.

[0033] The MCU 11 is connected to the LDO regulator 14 and a main negative bus LD connected to the negative electrode of the battery 12. The MCU 11 is also connected to each of the switches SW1 to SW4 and controls their on / off. The MCU 11 is also connected to the enable terminal of the operational amplifier 16 and controls the operational amplifier 16.

[0034] The MCU 11 inputs a control signal SIG1 to the control terminal of the switch SW1. In the following, it is assumed that when the control signal SIG1 is at a high level, the switch SW1 is in a conducting state, and when the control signal SIG1 is at a low level, the switch SW1 is in a cut-off state.

[0035] The MCU 11 inputs a control signal SIG2 to the control terminal of the switch SW2. In the following, it is assumed that when the control signal SIG2 is at a high level, the switch SW2 is in a conducting state, and when the control signal SIG2 is at a low level, the switch SW2 is in a cut-off state.

[0036] The MCU 11 inputs a control signal SIG3 to the control terminal of the switch SW3 and to the enable terminal of the operational amplifier 16. In the following, it is assumed that the switch SW3 is in a conducting state when the control signal SIG3 is at a high level, and that the switch SW3 is in a cut-off state when the control signal SIG3 is at a low level. It is also assumed that the operational amplifier 16 operates (produces output based on the input voltage) when the control signal SIG3 is at a high level, and stops output when the control signal SIG3 is at a low level.

[0037] The MCU 11 inputs a control signal SIG4 to the control terminal of the switch SW4. In the following, it is assumed that when the control signal SIG4 is at a high level, the switch SW4 is in a conducting state, and when the control signal SIG4 is at a low level, the switch SW4 is in a cut-off state.

[0038] A series circuit including a heater 40 and a switch SW2 is connected between the other end of the switch SW1a and the main negative bus LD. One end of the switch SW1b is connected to a power supply line to which the output voltage Vs is supplied. An RC series circuit including a resistor 22 and a capacitor 23 is connected between the other end of the switch SW1b and the main negative bus LD. Note that this RC series circuit is not limited to the configuration shown in FIG. 2 as long as it is a circuit that allows a time constant to be set. For example, a configuration in which a constant current circuit is provided instead of the resistor 22 may be used.

[0039] Specifically, the other end of switch SW1a is connected to one end of heater 40. The other end of heater 40 is connected to main negative bus LD via switch SW2. In addition, the other end of switch SW1b is connected to one end of resistor element 22. The other end of resistor element 22 is connected to main negative bus LD via capacitor 23.

[0040] One end of a resistor Rs is connected to a node N1 that connects the switch SW1a and the heater 40. The other end of the resistor Rs is connected to one end of a switch SW3. The other end of the switch SW3 is connected to a power supply line that supplies the output voltage Vs.

[0041] A non-inverting input terminal of an operational amplifier 16 is connected to a node N2 connecting the node N1 and the heater 40. An inverting input terminal of the operational amplifier 16 is connected to a node connecting the heater 40 and the switch SW2. The operational amplifier 16 is a differential amplifier that amplifies and outputs the voltage across the heater 40. An output terminal of the operational amplifier 16 is connected to an ADC 50b built into the MCU 11 and a first input terminal of a comparator 17. A circuit that generates a voltage value of a threshold TH1 is connected to a second input terminal of the comparator 17, and the threshold TH1 is input from this circuit. When the voltage value input to the first input terminal exceeds the threshold TH1, the comparator 17 outputs a high-level or low-level high-temperature detection signal. The threshold TH1 may be generated by resistively dividing the output voltage Vs. In this case, the threshold value TH1 also follows fluctuations in the output voltage Vs, as well as the output voltage of the operational amplifier 16, i.e., the voltage value input to the first input terminal of the comparator 17, thereby achieving the effect of canceling fluctuations in the output voltage Vs. More specifically, the input to the operational amplifier 16 is the output voltage Vs divided by resistors, and therefore, when the output voltage Vs fluctuates, the output voltage of the operational amplifier 16, i.e., the voltage value input to the first input terminal of the comparator 17, also fluctuates. If the threshold value TH1 is also generated by dividing the output voltage Vs by resistors, then when the output voltage Vs fluctuates, the threshold value TH1 also fluctuates. Therefore, it is possible to make the voltage values ​​input to both the first input terminal and the second input terminal of the comparator 17 follow fluctuations in the output voltage Vs.

[0042] One end of a resistor 24 is connected to a node connecting the resistor 22 and the capacitor 23 in the monitoring circuit 20. The other end of the resistor 24 is connected to the main negative bus LD via a switch SW4. A first input terminal of a comparator 21 is also connected to the node connecting the resistor 22 and the capacitor 23. A circuit that generates a voltage value of a threshold TH2 is connected to a second input terminal of the comparator 21, and the threshold TH2 is input from this circuit. When the voltage value input to the first input terminal of the comparator 21 exceeds the threshold TH2, the comparator 21 outputs a high-level or low-level abnormality detection signal. The threshold TH2 may be generated by resistor-dividing the output voltage Vs. In this case, the threshold TH2 follows fluctuations in the output voltage Vs, along with the voltage value input to the first input terminal of the comparator 21, thereby canceling out fluctuations in the output voltage Vs. More specifically, since the output voltage Vs is resistively divided and input to the operational amplifier 16, fluctuations in the output voltage Vs also fluctuate the voltage value input to the first input terminal of the comparator 21. If the threshold value TH2 is also generated by resistively dividing the output voltage Vs, fluctuations in the output voltage Vs will similarly fluctuate the threshold value TH2, and therefore it is possible to make the voltage values ​​input to both the first and second input terminals of the comparator 21 follow fluctuations in the output voltage Vs.

[0043] The output terminal of comparator 17 is connected to a first input terminal of comparator 18. The output terminal of comparator 21 is connected to a second input terminal of comparator 18. The output terminal of comparator 18 is connected to protection circuit 30. When at least one of an abnormality detection signal and a high temperature detection signal is input, comparator 18 outputs a high-level or low-level protection start signal for activating protection circuit 30. Comparator 18 may be configured as, for example, an OR circuit. Furthermore, comparator 18 may be configured such that the outputs of comparators 17 and 21 are open-drain outputs, and the outputs are connected by a wired OR.

[0044] The protection circuit 30 is a circuit for suppressing or stopping the supply of power to the heater 40, and various configurations can be adopted. For example, the protection circuit 30 is configured by a circuit for forcibly turning off the switch SW2 or the switch SW1a regardless of control from the MCU 11, a circuit for cutting off the power supply from the battery 12 to the switch SW1a (for example, a circuit for stopping the output of a boost circuit when a boost circuit is provided between the switch SW1a and the battery 12), etc.

[0045] When the MCU 11 transitions to an aerosol generation mode, which is an operation mode for generating aerosol, due to a user operation or the like, it controls the supply of power from the battery 12 to the heater 40. The above control includes heating control, which is control for supplying power to the heater 40 in order to heat the heater 40 (in other words, the base material 151), and measurement control, which is control for supplying power to the heater 40 in order to measure the temperature of the heater 40 (in other words, the base material 151).

[0046] 3 is a timing chart for explaining the operation of the MCU 11 in the aerosol generation mode, which shows the time variations of the control signal SIG3 of the switch SW3, the control signal SIG1 of the switch SW1, the control signal SIG4 of the switch SW4, and the voltage of the capacitor 23.

[0047] When the MCU 11 transitions to the aerosol generation mode, it repeatedly executes a set of heating control and measurement control in a predetermined control cycle TC while controlling the switch SW2 to the on state. Figure 3 shows a heating period TH during which heating control is performed, a measurement period TD during which measurement control is performed, and the control cycle TC of the MCU 11. The heating period TH and the measurement period TD each have a predetermined length, and in the example of Figure 3, the start timing of the control cycle TC coincides with the start timing of the measurement period TD, the end timing of the measurement period TD coincides with the start timing of the heating period TH, and the end timing of the heating period TH coincides with the end timing of the control cycle TC.

[0048] Heating control is a control in which the switch SW3 is turned off and the switch SW1 is turned on for a variable time during the heating period TH. The MCU 11 performs PWM (pulse width modulation) control to control the ratio (duty ratio) of the variable time to the length of the heating period TH. The duty ratio is varied between 0% and 100%, for example. Figure 3 shows an example in which the duty ratio is 100%.

[0049] By this heating control, power is supplied from the power source 12 to the heater 40, causing the heater 40 to heat. The power supplied to the heater 40 by this heating control is referred to as heating power, and the voltage applied to the heater 40 by this heating control is referred to as heating voltage. The timing at which the application of the heating voltage to the heater 40 ends during the heating period TH coincides with the end timing of the heating period TH. Therefore, the control period TC is the period during which the heating power is supplied to the heater 40.

[0050] During the heating period TH, while the switch SW1 is in the ON state, the output voltage Vs is supplied to the RC series circuit consisting of the resistor element 22 and the capacitor 23. As shown in FIG. 3, the MCU 11 controls the switch SW4 to the OFF state during the heating period TH. Therefore, during the heating period TH, the capacitor 23 is charged by the output voltage Vs. It should be noted that the amount of charge charged to the capacitor 23 during one heating period TH increases as the duty ratio increases (as the time for which the heating voltage is applied to the heater 40 increases).

[0051] The measurement control is a control that operates the operational amplifier 16 during the measurement period TD, turns the switch SW1 off, and turns the switch SW3 on to supply a measurement power (output voltage Vs) lower than the heating power to the resistance element Rs and the heater 40. The voltage applied to the heater 40 by this measurement control is referred to as the measurement voltage. Because the electrical resistance value of the resistance element Rs is sufficiently larger than the electrical resistance value of the heater 40, the measurement voltage is sufficiently smaller than the heating voltage.

[0052] As shown in Fig. 3, during the measurement period TD, the MCU 11 also executes discharge control to turn on the switch SW4. This discharge control is executed at the start of each control period TC, and therefore can be said to be executed at a timing based on the control period TC. Furthermore, since this discharge control is executed at the end of each heating period TH, it can also be said to be executed at a timing synchronized with the end timing of the heating period TH. The synchronization of the two timings means that the difference between the two timings is equal to or less than a threshold (ideally, 0), and includes cases where the two timings coincide, as well as cases where there is a slight difference between the two timings due to circuit delay time or the like.

[0053] This measurement control supplies measurement power from the LDO regulator 14 to a voltage divider circuit consisting of the resistor element Rs and the heater 40. The electrical resistance of the resistor element Rs is set to a value significantly greater than the electrical resistance of the heater 40. Therefore, while measurement control is being performed, a small current can be passed through the heater 40. In this state, the operational amplifier 16 outputs a voltage corresponding to the voltage applied to the heater 40. The output voltage of the operational amplifier 16 increases as the electrical resistance of the heater 40 increases. Here, it is assumed that the heater 40 has a positive-temperature-coefficient (PTC) characteristic. Therefore, the higher the temperature of the heater 40 (in other words, the temperature of the aerosol source), the higher the output voltage of the operational amplifier 16. In this state, the MCU 11 acquires the output value of the ADC 50b and acquires the temperature of the heater 40 based on this output value. The MCU 11 adjusts the above-described duty ratio based on the acquired temperature of the heater 40.

[0054] As shown in Fig. 3, during measurement period TD, switch SW4 is turned on by discharge control. Therefore, the voltage charged to capacitor 23 during heating period TH immediately before measurement period TD is discharged by discharge control executed during that measurement period TD. The time constant of the RC series circuit formed by resistance element 22 and capacitor 23 is set to a value that allows the entire maximum voltage that can be charged to capacitor 23 by one heating control (the voltage value that can be charged when the duty ratio is 100%, voltage value V1 in Fig. 3) to be discharged during measurement period TD.

[0055] Therefore, the voltage of capacitor 23 repeatedly rises from an initial value (for example, 0 V) ​​due to heating control, and then returns to the initial value due to discharge control thereafter. In other words, as long as MCU 11 appropriately executes discharge control, the voltage of capacitor 23 does not exceed the maximum voltage (voltage value V1).

[0056] The monitoring circuit 20 is provided to determine whether the voltage of the capacitor 23 is at a value that cannot be reached when the MCU 11 is operating normally, and to activate the protection circuit 30 if such a state occurs.

[0057] Specifically, in the aerosol generation mode, the comparator 21 of the monitoring circuit 20 compares the voltage of the capacitor 23 with a threshold value TH2 and outputs an abnormality detection signal when the voltage of the capacitor 23 exceeds the threshold value TH2. The threshold value TH2 is set to a value greater than the maximum voltage (voltage value V1). The threshold value TH2 may be generated by resistively dividing the output voltage Vs. In this case, the threshold value TH2 follows fluctuations in the output voltage Vs, as well as the voltage value input to the first input terminal of the comparator 21, thereby canceling fluctuations in the output voltage Vs. More specifically, since the input to the operational amplifier 16 is the output voltage Vs divided by a resistor and input thereto, fluctuations in the output voltage Vs also cause fluctuations in the voltage value input to the first input terminal of the comparator 21. When the threshold value TH2 is also generated by resistively dividing the output voltage Vs, fluctuations in the output voltage Vs cause the threshold value TH2 to fluctuate in the same way. Therefore, both the voltage values ​​input to the first input terminal and the second input terminal of the comparator 21 can be made to follow fluctuations in the output voltage Vs.

[0058] For example, if the MCU 11 is unable to execute discharge control for some reason, the voltage of the capacitor 23 will exceed the voltage value V1. In FIG. 3, for example, assume that the discharge control that should have been executed during the measurement period TD, which starts at time ta, is not executed. In this case, as shown by the dashed line in the figure, during the measurement period TD and heating period TH immediately after time ta, the voltage of the capacitor 23 continues to rise, exceeding the voltage value V1 and the threshold value TH2. When this state occurs, the comparator 21 will output an abnormality detection signal.

[0059] Fig. 4 is a diagram showing an example of the protection circuit 30. Fig. 4 shows a resistance element 32 connected to the MCU 11, an N-channel MOSFET which is an example of the switch SW2, a resistance element 33 connected to the gate and source of the N-channel MOSFET, and a resistance element 31 connected to the comparator 18.

[0060] One end of the resistor element 32 is connected to the MCU 11, and the other end of the resistor element 32 is connected to the gate of the N-channel MOSFET. The drain of the N-channel MOSFET is connected to the heater 40, and the source of the N-channel MOSFET is connected to ground (main negative bus LD). The other end of the resistor element 31 is connected to a node N3 that connects the gate of the N-channel MOSFET and the resistor element 32. One end of the resistor element 31 is connected to the output terminal of the comparator 18. The node that connects the node N3 and the gate of the N-channel MOSFET is connected to ground (main negative bus LD) via a resistor element 33. In the example of FIG. 4, the protection circuit 30 is composed of a section from the comparator 18 to the node N3, and the resistor element 32.

[0061] Resistance element 32 is a resistor that limits the value of the current that flows from MCU 11 to comparator 18, and also serves as the gate resistor of the N-channel MOSFET. Resistance element 31 is a resistor that limits the value of the current that flows from the gate of the N-channel MOSFET to comparator 18. Resistance element 33 is a resistor that fixes the gate potential of the N-channel MOSFET. In the example shown in FIG. 4, when a low-level protection start signal is output from comparator 18, the gate potential of the N-channel MOSFET becomes low, and switch SW2 is turned off. This disables the supply of power to heater 40, and heating by heater 40 is stopped.

[0062] 4, the position of the resistive element 31 may be changed to between the node connecting the resistive element 33 and the gate of the N-channel MOSFET and the node N3. Also, the resistive elements 32 and 31 may be combined into one resistive element, and this resistive element may be placed in the position of the resistive element 31.

[0063] (heating profile) The MCU 11 controls the supply of heating power to the heater 40 according to a heating profile that determines the temperature transition of the heater 40 (in the case of induction heating, a susceptor that is induction heated by a reactor corresponding to the heater 40).

[0064] FIG. 5 is a diagram showing an example of a heating profile. The horizontal axis in the diagram represents the elapsed time since the aerosol generation mode was entered, and the vertical axis in the diagram represents the temperature of the heater 40. The heating profile shown in FIG. 5 is composed of a temperature increase period T1 during which the temperature of the heater 40 is increased to a target temperature TP1, a temperature maintenance period T2 during which the temperature of the heater 40 is maintained at the target temperature TP1, a cooling period T3 during which the temperature of the heater 40 is decreased to a target temperature TP3, a temperature maintenance period T4 during which the temperature of the heater 40 is maintained at the target temperature TP3, a temperature increase period T5 during which the temperature of the heater 40 is increased to a target temperature TP2, a temperature maintenance period T6 during which the temperature of the heater 40 is maintained at the target temperature TP2, and a cooling period T7 during which heating of the heater 40 is stopped.

[0065] Target temperature TP1 is greater than target temperature TP2, which is greater than target temperature TP3. The gradient of the temperature transition of heater 40 during temperature rise period T1 is greater than the gradient of the temperature transition of heater 40 during temperature rise period T5, and is the greatest among all periods constituting the heating profile.

[0066] Thus, the heating profile includes a first period (temperature rise period T1, T5) in which the slope of the temperature transition of the heater 40 is greater than a slope threshold (e.g., 0), and a second period (temperature maintenance period T2, T4, T6) in which the slope of the temperature transition of the heater 40 is equal to or less than the slope threshold.

[0067] When the MCU 11 transitions to the aerosol generation mode, it repeatedly executes a set of measurement control, heating control, and discharge control so that the temperature of the heater 40 converges to the target temperature TP1 over the temperature rise period T1. Next, the MCU 11 repeatedly executes a set of measurement control, heating control, and discharge control so that the temperature of the heater 40 is maintained at the target temperature TP1 during the temperature maintenance period T2. Next, the MCU 11 executes only the measurement control and discharge control among the measurement control, heating control, and discharge control, and stops the heating control until the temperature of the heater 40 drops to the target temperature TP3. Note that executing only the measurement control and discharge control among the measurement control, heating control, and discharge control does not prevent the MCU 11 from performing control other than the measurement control, heating control, or discharge control. Next, the MCU 11 repeatedly executes a set of measurement control, heating control, and discharge control during the temperature maintenance period T4 so that the temperature of the heater 40 is maintained at the target temperature TP3. Next, the MCU 11 repeatedly executes a set of measurement control, heating control, and discharge control so that the temperature of the heater 40 converges to the target temperature TP2 over the temperature rise period T5. Next, the MCU 11 repeatedly executes a set of measurement control, heating control, and discharge control so that the temperature of the heater 40 is maintained at the target temperature TP2 during the temperature maintenance period T6. Finally, the MCU 11 ends the measurement control, heating control, and discharge control to lower the temperature of the heater 40. Hereinafter, the periods during which control is performed according to different set conditions for the temperature rise period T1, temperature maintenance period T2, temperature maintenance period T4, temperature rise period T5, and temperature maintenance period T6 will be referred to as period S1, period S2, period S4, period S5, and period S6, respectively.

[0068] The period during which inhalation by the user is recommended is from the start of period S2 to the end of period S7.

[0069] During periods S1 and S5, the temperature of heater 40 needs to be increased, so the above-mentioned duty ratio tends to be large. In particular, during period S1, it is preferable to increase the temperature of heater 40 from the start of heating to a temperature suitable for starting to suction aerosol in as short a time as possible, and the temperature rise gradient is steep, so the duty ratio tends to be particularly large. On the other hand, during periods S2, S4, and S6, it is sufficient to maintain the temperature of heater 40, so the above-mentioned duty ratio tends to be small compared to periods S1 and S5.

[0070] During the cooling period T3, power supply to the heater 40 is stopped. Alternatively, during this period, only measurement control and discharge control may be performed. Therefore, it should be noted that at the start of period S4, the voltage of the capacitor 23 is at its initial value. When power supply to the heater 40 is stopped, the temperature of the heater 40 may be measured by a thermistor (not shown) installed near the heater 40.

[0071] As described above, in the power supply unit including the electronic circuit 10, the voltage of the capacitor 23, which is charged by a single supply of heating power to the heater 40, is completely discharged by a single discharge control by the MCU 11. Therefore, it is possible to determine a state in which the MCU 11 is not performing discharge control (a state in which an abnormality has occurred in the MCU 11) based on the magnitude of the voltage of the capacitor 23. Since the protection circuit 30 limits the supply of heating power to the heater 40 when the voltage of the capacitor 23 is higher than the threshold value TH2, even if an abnormality has occurred in the MCU 11, the power supply to the heater 40 can be appropriately limited, thereby improving the safety of the power supply unit.

[0072] Furthermore, with the power supply unit including the electronic circuit 10, when heating control is being performed, the operational amplifier 16 stops outputting, and therefore the comparator 17 does not output a high-temperature detection signal. During heating control, a large amount of heating power may be supplied to the heater 40, and therefore, when the operational amplifier 16 is operating, the output of the operational amplifier 16 is likely to be large. If the operational amplifier 16 is operating during heating control, this large output from the operational amplifier 16 may be input to the comparator 17, causing the comparator 17 to output a high-temperature detection signal. In this embodiment, the operational amplifier 16 operates only during the period when measurement control is being performed. Therefore, if the temperature of the heater 40 becomes excessively high, the comparator 17 can appropriately output a high-temperature detection signal. In this way, the protection circuit 30 can be operated appropriately to enhance safety.

[0073] Modifications of the electronic circuit 10 will now be described.

[0074] (First Modification) Fig. 6 is a diagram showing an electronic circuit 10A, which is a modified example of the electronic circuit 10 shown in Fig. 2. The electronic circuit 10A shown in Fig. 6 has the same configuration as the electronic circuit 10, except that a comparator 19 is added and the operational amplifier 16 is changed to one that operates constantly in the aerosol generation mode.

[0075] A first input terminal of the comparator 19 is connected to the output terminal of the comparator 17. A second input terminal of the comparator 19 is connected to the MCU 11. A control signal SIG3 is input to the second input terminal of the comparator 19 from the MCU 11. An output terminal of the comparator 19 is connected to the first input terminal of the comparator 18.

[0076] In the electronic circuit 10A, the operational amplifier 16 operates regardless of whether the heater 40 is being controlled by heating control or measurement control. Therefore, even if the temperature of the heater 40 is not excessively high, the operational amplifier 16 outputs a large voltage during heating control. Comparing this voltage with the threshold TH1 results in the comparator 17 outputting a high-temperature detection signal. The comparator 19 is configured to output a high-temperature detection signal only when it receives a high-temperature detection signal from the comparator 17 while the MCU 11 is inputting a high-level control signal SIG3 (i.e., while only measurement control is being performed among heating control and measurement control). Therefore, even if the temperature of the heater 40 becomes excessively high, the comparator 19 can appropriately output a high-temperature detection signal. The first modification has the advantage that the operational amplifier 16 can be constantly operated, thereby stabilizing the output of the operational amplifier 16. Another advantage is that the operational amplifier 16 can be configured without a control function based on a control signal. Note that the state in which only measurement control is being performed among heating control and measurement control does not prevent the MCU 11 from performing control other than heating control or measurement control.

[0077] Note that the second input terminal of the comparator 19 may receive a signal capable of determining whether heating control or measurement control is being performed, and the control signal SIG1 may be input from the MCU 11. In this case, the comparator 19 may be configured to output a high-temperature detection signal only when it receives a high-temperature detection signal from the comparator 17 while the control signal SIG1 is at a low level (i.e., while no heating voltage is being applied to the heater 40). Even with this configuration, the comparator 19 can appropriately output a high-temperature detection signal when the temperature of the heater 40 becomes excessively high. Alternatively, for example, a current flowing between the switch SW1a and the node N1 may be detected, and if a current is detected, it may be determined that heating control is being performed and a signal may be input to the second input terminal of the comparator 19. Alternatively, the comparator 19 may be configured as an AND circuit.

[0078] (Second Modification) In the electronic circuit 10 or the electronic circuit 10A, the time constant of the RC series circuit formed by the resistance element 22 and the capacitor 23 may be set so that the voltage charged to the capacitor 23 by one heating control is not completely discharged during the measurement period TD. In this case, the condition for the threshold value TH2 changes.

[0079] For example, in period S1, the duty ratio tends to be larger than in other periods, so a maximum number of consecutive executions N of heating control at the maximum duty ratio (N is a natural number equal to or greater than 2) is set. The maximum number of consecutive executions N is a value that indicates that performing heating control at the maximum duty ratio more than this number of times in succession is deemed to be a design error.

[0080] In the second variant, the threshold value TH2 is set to a value reached by applying a heating voltage to the heater 40 in the heating period TH (with the maximum DUTY ratio) immediately after the set of the heating period TH (with the maximum DUTY ratio) and the measurement period TD immediately thereafter is repeated N times as described above.

[0081] Fig. 7 is a timing chart for explaining the operation of MCU 11 in the second modified example. The timing chart shown in Fig. 7 is for when control is executed during the temperature rise period T1, and the voltage waveform of capacitor 23 is changed from that shown in Fig. 3.

[0082] In the example of FIG. 7, the maximum number of consecutive executions N during period S1 is set to "4." Also, in the example of FIG. 7, the voltage of capacitor 23 that cannot be fully discharged during measurement period TD is set to voltage value Va. Then, a value obtained by adding three times voltage value Va to voltage value V1 is set as threshold value TH2. By setting threshold value TH2 in this manner, heating control is performed five times from a state in which the voltage of capacitor 23 is at its initial value, and the voltage of capacitor 23 exceeds threshold value TH2. When the voltage of capacitor 23 exceeds threshold value TH2, heating control is performed in excess of the maximum number of consecutive executions N (=4), and there is a possibility that an abnormality has occurred in MCU 11. Therefore, by activating protection circuit 30, overheating of heater 40 can be prevented.

[0083] Note that during period S1, the duty ratio during heating control may be smaller than the maximum duty ratio. Even if an abnormality occurs in MCU 11 and heating control is repeated at a duty ratio smaller than the maximum duty ratio, the voltage of capacitor 23 exceeds threshold value TH2 during some heating period TH. Therefore, it is possible to detect an abnormality in MCU 11. Also, in FIG. 7, for example, if discharge control is not performed during the second measurement period TD, the voltage of capacitor 23 exceeds threshold value TH2 during the second heating period TH, and therefore protection circuit 30 will operate even if an abnormality related to discharge control occurs.

[0084] As described above, in the second modified example, even when the MCU 11 is properly executing the discharge control, the supply of heating power to the heater 40 (i.e., the heating control) is repeated, thereby gradually increasing the voltage of the capacitor 23. If the heating control is not properly executed, the voltage of the capacitor 23 exceeds the threshold TH2, and the protection circuit 30 is activated. In other words, if the MCU 11 is properly executing the discharge control but is unable to properly execute the heating control, the power supply to the heater 40 can be limited, preventing overheating of the heater 40 and improving safety.

[0085] According to the second modification, the comparator 21 determines whether or not there is an abnormality in the heating control by the MCU 11, and activates the protection circuit 30. Heating control is a more advanced control than discharge control. In the second modification, the safety of the power supply unit can be further improved by detecting an abnormality in such advanced control.

[0086] Note that the duty ratio tends to be smaller during periods S2, S4, and S6 than during other periods. Therefore, the rate at which the voltage of capacitor 23 increases due to the repetition of heating control and discharge control is slower than the rate at which the voltage of capacitor 23 increases during period S1. In other words, during periods S2, S4, and S6, unless the set of heating period TH and measurement period TD is repeated a number of times sufficiently greater than the above-mentioned N, the voltage of capacitor 23 will not exceed threshold value TH2, making it difficult to detect an abnormality in MCU 11 early.

[0087] Therefore, during periods S2, S4, and S6, it is preferable to set threshold value TH2 to a value (=threshold value TH2a) smaller than that during period S1. For example, threshold value TH2a is set to a value reached by application of a heating voltage to heater 40 during heating period TH (duty ratio is half the maximum) immediately after a set of heating period TH (duty ratio is half the maximum) and measurement period TD immediately thereafter is repeated M times (M is a natural number of 2 or more). By setting threshold value TH2a in this manner, it is possible to quickly detect a state in which heating control is not being performed appropriately during periods S2, S4, and S6 as well, and activate protection circuit 30.

[0088] For the same reason, in period S5 when the DUTY ratio tends to be larger than in periods S2, S4, and S6 and smaller than in period S1, it is preferable to set threshold value TH2 to a value (=threshold value TH2b) smaller than in period S1 and larger than in periods S2, S4, and S6.

[0089] Note that the period S2 is a period in which the temperature of the heater 40 is maintained at a high temperature, and therefore the duty ratio tends to be larger than in periods S4 and S6. Therefore, in period S2, the threshold value TH2 may be set to the same value as that set in period S1, for example.

[0090] Furthermore, the user's suction operation occurs after period S2, and when the suction operation is performed, the temperature of the heater 40 temporarily drops. Therefore, in order to return the temperature of the heater 40 to the target temperature, the MCU 11 performs control to temporarily increase the duty ratio. In other words, the suction operation may temporarily increase the amount of increase in the voltage of the capacitor 23. Therefore, during periods other than period S1, if a suction operation is detected, the preset threshold value TH2 may be increased by a predetermined amount for a certain period of time. This allows the MCU 11 to perform an abnormality determination with high accuracy.

[0091] The time constant of the RC series circuit of the monitoring circuit 20 varies from one device to another. Therefore, the MCU 11 may, for example, control the switch SW2 to the off state and control the switch SW1 and the switch SW4 to on / off in the same manner as in actual heating control and discharge control, monitor the voltage of the capacitor 23, determine how many volts it takes for the voltage of the capacitor 23 to reach from its initial value (0 V), and perform a calibration process to correct the predetermined thresholds TH2, TH2a, and TH2b based on the determination result. Alternatively, the MCU 11 may, for example, control the switch SW1 to the off state and turn off the switch SW4 in the same manner as in actual discharge control, monitor the voltage of the capacitor 23, determine how long it takes for the voltage of the capacitor 23 to be discharged to how many volts, and perform a calibration process to correct the predetermined thresholds TH2, TH2a, and TH2b based on the determination result. For example, the MCU 11 may determine how long it takes for the voltage of the capacitor 23 to be discharged to its initial value (0 V), and perform a calibration process based on the determination result. Furthermore, the MCU 11 may perform both calibration related to charging of the capacitor 23 and calibration related to discharging of the capacitor 23. This allows individual differences to be absorbed and enables highly accurate abnormality determination of the MCU 11. This calibration process may be performed at the time of manufacturing the power supply unit, at startup, or when switching to the aerosol generation mode, etc.

[0092] The threshold value in this calibration process may be changed using an IC built into the power supply unit, a DA converter provided in the MCU 11, an external DA converter, a direct digital synthesizer, etc. Alternatively, a plurality of voltage divider circuits having different electrical resistance values ​​may be provided, one of the voltage divider circuits may be selected, and the output of the selected voltage divider circuit may be used as the threshold value.

[0093] (Third Modification) Fig. 8 is a diagram showing an electronic circuit 10B that is a modified example of the electronic circuit 10 shown in Fig. 3. The electronic circuit 10B shown in Fig. 8 has the same configuration as the electronic circuit 10, except that a comparator 25 is added to the monitoring circuit 20, and the threshold value TH2 input to the comparator 21 is changed to a threshold value TH3.

[0094] The threshold value TH3 is the voltage value that the voltage of the capacitor 23 reaches after a predetermined time has elapsed from the initial value state (the state at the start of the period S1 and the state at the start of the period S4) when heating is performed by the heater 40 according to the heating profile shown in Fig. 5. The threshold value TH3 is set to, for example, the average value of multiple actual measurement values.

[0095] For example, if the MCU 11 is operating normally, the voltage of the capacitor 23 will reach the threshold value TH3 when time t1 has elapsed since the start of control in the temperature rise period T1. Similarly, if the MCU 11 is operating normally, the voltage of the capacitor 23 will reach the threshold value TH3 when time t2 has elapsed since the start of control in the temperature maintenance period T4. Times t1 and t2 are values ​​obtained by actual measurements, and time t1 is shorter than time t2.

[0096] With times t1 and t2 determined in this manner, if an abnormality occurs in MCU 11 and the duty ratio continues to be unintentionally large during periods S1 and S2, the voltage of capacitor 23 will reach threshold value TH3 at a timing earlier than the time t1 has elapsed since the start of period S1. Also, if an abnormality occurs in MCU 11 and the duty ratio continues to be unintentionally small during periods S1 and S2, the voltage of capacitor 23 will reach threshold value TH3 at a timing later than the time t1 has elapsed since the start of period S1.

[0097] That is, in periods S1 and S2, if there is a large difference between the time t1 and the time elapsed from when the voltage of capacitor 23 was at its initial value (0 V) at the time the voltage of capacitor 23 reached threshold value TH3, then MCU 11 is unable to control the duty ratio normally. Similarly, in periods S4 and after, if there is a large difference between the time t2 and the time elapsed from when the voltage of capacitor 23 was at its initial value (0 V) (start point of period S4) at the time the voltage of capacitor 23 reached threshold value TH3, then MCU 11 is unable to control the duty ratio normally.

[0098] One of the two input terminals of the comparator 25 of the monitoring circuit 20 receives a time t1 as a threshold value TH4 during periods S1 and S2, and receives a time t2 as a threshold value TH4 during periods S4 and thereafter. The other of the two input terminals of the comparator 25 is connected to the MCU 11. Information on the elapsed time t3 from the start of period S1 or period S4 is input from the MCU 11 to the other input terminal. The comparator 25 has an enable terminal connected to the output terminal of the comparator 21. The output terminal of the comparator 25 is connected to the second input terminal of the comparator 18.

[0099] In the monitoring circuit 20 of the electronic circuit 10B, when the output of the comparator 21 becomes high level (in other words, when the voltage of the capacitor 23 reaches the threshold value TH3), the comparator 25 is enabled and compares the elapsed time t3 with the threshold value TH4 (time t1 or time t2). If the result of this comparison shows that the difference between the elapsed time t3 and the threshold value TH4 is equal to or greater than the difference threshold value (i.e., there is an abnormality in the heating control of the MCU 11), the comparator 25 outputs a high-level signal, and if the difference is less than the difference threshold value, the comparator 25 outputs a low-level signal. When the voltage input to either of the two input terminals of the comparator 18 becomes high level, the comparator 25 outputs a protection start signal to activate the protection circuit 30.

[0100] In this way, in the electronic circuit 10B, the presence or absence of an abnormality in the heating control of the MCU 11 can be determined based on a comparison between the threshold value TH4 and the time t3 elapsed from the initial value (0 V) until the voltage of the capacitor 23 reaches the threshold value TH3, thereby improving the safety of the power supply unit. The configuration of the monitoring circuit 20 in the electronic circuit 10B can also be applied to the electronic circuit 10A.

[0101] In the above description, the timing at which the voltage of capacitor 23 reaches the initial value during the period in which control is performed according to the heating profile is the start point of each of period S1 and period S4.

[0102] However, for example, at the start of each of periods S2, S5, and S6, a period may be provided in which heating control is not performed but only discharge control and measurement control are performed, and the voltage of capacitor 23 may be returned to its initial value. In this case, it is preferable to set threshold value TH4 in periods S1 and S5 smaller than threshold value TH4 set in periods S2, S4, and S6.

[0103] More preferably, the threshold value TH4 in period S1 is set to the smallest value, the threshold value TH4 in period S5 is set to a value greater than the threshold value TH4 in period S1, and the threshold value TH4 in periods S2, S4, and S6 is set to a value greater than the threshold value TH4 in period S5. In this way, by setting the threshold value TH4 appropriate for the content of heating control, it is possible to more accurately determine whether or not there is an abnormality in MCU 11.

[0104] Furthermore, when the user performs a suction operation, the threshold value TH4 may be decreased by a predetermined amount from a preset value, thereby enabling the determination of whether or not there is an abnormality in the MCU 11 to be performed with higher accuracy.

[0105] The threshold value TH4 is preferably adjustable by a calibration process similar to that described for the electronic circuits 10 and 10A.

[0106] In the electronic circuits 10 and 10B, the monitoring circuit 20 and the comparator 18 may be omitted, and the output of the comparator 17 may be directly connected to the protection circuit 30. Even in this configuration, when the temperature of the heater 40 is high, the protection circuit 30 can be appropriately activated by a high temperature detection signal, thereby improving safety. Also, in the electronic circuits 10 and 10B, the comparators 17 and 18 may be omitted, and the output of the monitoring circuit 20 may be directly connected to the protection circuit 30. Even in this configuration, when an abnormality occurs in the MCU 11, the protection circuit 30 can be appropriately activated by an abnormality detection signal, thereby improving safety.

[0107] In the electronic circuit 10A, the monitoring circuit 20 and the comparator 18 may be omitted, and the output of the comparator 19 may be directly connected to the protection circuit 30. Even in this configuration, when the temperature of the heater 40 is high, the protection circuit 30 can be appropriately activated by a high temperature detection signal, thereby improving safety. Also, in the electronic circuit 10A, the comparators 17, 18, and 19 may be omitted, and the output of the monitoring circuit 20 may be directly connected to the protection circuit 30. Even in this configuration, when an abnormality occurs in the MCU 11, the protection circuit 30 can be appropriately activated by an abnormality detection signal, thereby improving safety.

[0108] In the electronic circuit 10, the electronic circuit 10A, and the electronic circuit 10B, the switch SW1b may be omitted, a boost circuit may be provided between the main positive bus LU and the switch SW1a, and one end of the resistive element 22 may be connected to the node N1.

[0109] If the power supply unit 110 is configured so that the first container and the second container are detachable and has a heating section for heating the second container, the heaters 40 in each of the electronic circuit 10, the electronic circuit 10A, and the electronic circuit 10B can be replaced with this heating section, thereby preventing overheating of the second container and improving safety.

[0110] This specification describes at least the following items. Note that the components in parentheses correspond to those in the above-described embodiment, but are not limited to these.

[0111] (1) a power source (battery 12); a processor (MCU11) that controls the supply of heating power from the power source to a heating element (heater 40 (reactor and susceptor in the case of induction heating)) for heating the aerosol source and / or flavor source; a protection circuit (protection circuit 30) that limits the supply of the heating power to the heating element; a monitoring circuit (monitoring circuit 20) including a charging circuit (resistance element 22 and capacitor 23) capable of storing electricity using power (output voltage Vs) from the power supply when heating power is supplied from the power supply to the heating element, and which outputs a signal (abnormality detection signal) to activate the protection circuit based on the voltage of the charging circuit; The processor is a power supply unit (power supply unit 110) of the aerosol generating device that performs discharge control to discharge the voltage of the charge circuit at a timing (start timing of the measurement period TD) based on the supply period (control period TC) of the heating power to the heating element.

[0112] According to (1), for example, by making it possible for the voltage of the charging circuit, which is charged by a single supply of heating power to the heating element, to be completely discharged by a single discharge control by the processor, it becomes possible to determine a state in which the processor is not discharging the charging circuit (a state in which an abnormality has occurred in the processor) based on the magnitude of the voltage of the charging circuit. For example, if the voltage of the charging circuit is greater than a threshold, the monitoring circuit outputs a signal to activate the protection circuit, thereby appropriately limiting the power supply to the heating element even if an abnormality has occurred in the processor, thereby improving the safety of the aerosol generating device. Furthermore, according to (1), for example, by preventing the voltage of the charging circuit, which is charged by a single supply of heating power to the heating element, from being completely discharged by a single discharge control by the processor, it becomes possible to determine a state in which the processor is not properly supplying heating power to the heating element (a state in which an abnormality has occurred in the processor) based on the magnitude of the voltage of the charging circuit. For example, when the voltage of the charging circuit is greater than a threshold, the monitoring circuit outputs a signal to activate a protection circuit, thereby appropriately limiting the power supply to the heating element when the processor is not properly supplying heating power to the heating element, thereby improving the safety of the aerosol generation device. Furthermore, according to (1), for example, by configuring the voltage of the charging circuit, which is charged by a single supply of heating power to the heating element, not to be completely discharged by a single discharge control by the processor, and by configuring the time elapsed until the voltage of the charging circuit reaches a threshold value to be within a predetermined range when the processor is properly supplying heating power to the heating element, it is possible to determine whether the processor is not properly supplying heating power to the heating element based on the time elapsed until the voltage of the charging circuit reaches the threshold value. For example, if this elapsed time falls outside the predetermined range, the monitoring circuit outputs a signal to activate the protection circuit, thereby appropriately limiting the power supply to the heating element when the processor is not properly supplying heating power to the heating element, thereby improving the safety of the aerosol generating device.

[0113] (2) A power supply unit for the aerosol generating device according to (1), A power supply unit of an aerosol generating device, wherein the timing is synchronized with the end timing of control of supplying the heating power to the heating element.

[0114] According to (2), the charge circuit is discharged each time heating power is supplied. Therefore, compared to a configuration in which the charge circuit is discharged once for every two heating power supplies, the capacity of the charge circuit can be reduced, which enables reduction in manufacturing costs and miniaturization.

[0115] (3) A power supply unit for the aerosol generating device according to (1) or (2), The monitoring circuit outputs a signal to activate the protection circuit based on a result of comparing the voltage of the charging circuit with a first threshold value (threshold value TH2), the power supply unit of the aerosol generating device.

[0116] According to (3), the supply of heating power to the heating element can be limited simply by comparing the voltage with a threshold value, thereby simplifying the control.

[0117] (4) A power supply unit for the aerosol generating device according to (3), the voltage of the charging circuit charged by a single supply of the heating power to the heating element can be fully discharged by the discharge control; A power supply unit of an aerosol generating device, wherein the first threshold value is greater than a maximum voltage (voltage value V1) of the charging circuit charged by a single supply of the heating power to the heating element.

[0118] According to (4), if the charge circuit does not discharge due to an abnormality in the processor, the voltage of the charge circuit exceeds the first threshold, so that an abnormality in the processor's discharge control can be detected and the supply of heating power to the heating element can be limited.

[0119] (5) A power supply unit for the aerosol generating device according to (3), A power supply unit for an aerosol generating device, wherein the voltage of the charging circuit charged by a single supply of the heating power to the heating element is greater than the voltage of the charging circuit discharged by the discharge control.

[0120] According to (5), the supply of heating power to the heating element and discharge control are repeated to increase the voltage of the charge circuit. By setting the first threshold so that the voltage of the charge circuit does not exceed the first threshold when the supply of heating power is being performed appropriately, it becomes possible to determine whether the supply of heating power is being performed appropriately based on the magnitude relationship between the first threshold and the voltage of the charge circuit.

[0121] (6) A power supply unit for the aerosol generating device according to (5), A power supply unit of an aerosol generating device, wherein the first threshold is a value reached by charging the charge circuit during a period in which the heating power is supplied to the heating element after charging and discharging of the charge circuit have been repeated multiple times.

[0122] According to (6), when excessive charging and discharging is repeated, the voltage of the charging circuit exceeds the first threshold, making it possible to detect a state in which excessive heating power is unintentionally supplied to the heating element.

[0123] (7) A power supply unit for the aerosol generating device according to (5) or (6), the processor controls the supply of the heating power to the heating element in accordance with a heating profile that defines a temperature transition of the heating element; A power supply unit of an aerosol generating device, wherein the first threshold value is variably controlled based on the heating profile during a period in which the supply control is performed in accordance with the heating profile.

[0124] According to (7), an appropriate first threshold is set according to the heating profile, so that the protection circuit can be operated appropriately.

[0125] (8) A power supply unit for the aerosol generating device according to (7), the heating profile includes a first period (temperature rise periods T1, T5) in which the gradient of the temperature transition is greater than a gradient threshold, and a second period (temperature maintenance periods T2, T4, T6) in which the gradient of the temperature transition is equal to or less than the gradient threshold, The power supply unit of the aerosol generation device, wherein the first threshold value is set to a different value in the first period than in the second period.

[0126] According to (8), an appropriate first threshold is set according to the heating profile, so that the protection circuit can be operated appropriately.

[0127] (9) A power supply unit for the aerosol generating device according to (8), A power supply unit of an aerosol generation device, wherein the first threshold set in the first period is greater than the first threshold set in the second period.

[0128] According to (9), since more heating power is supplied to the heating element during the first period than during the second period, the voltage of the charging circuit tends to increase. Therefore, by increasing the first threshold during the first period, the protection circuit can be operated appropriately.

[0129] (10) A power supply unit for the aerosol generating device according to (7), The heating profile includes a first period (temperature rise period T1) in which the gradient of the temperature transition is maximum, A power supply unit of an aerosol generating device, wherein the first threshold value set for the first period is set to a maximum value during a period in which the supply control is performed according to the heating profile.

[0130] According to (10), during the first period, a large amount of heating power is supplied to the heating element, and therefore the voltage of the charging circuit tends to increase. Therefore, by increasing the first threshold during this period, the protection circuit can be operated appropriately.

[0131] (11) A power supply unit for the aerosol generating device according to any one of (5) to (10), a suction sensor (suction sensor 15) that detects a suction operation by a user; The first threshold is temporarily increased when the inhalation action is detected, the power supply unit of the aerosol generating device.

[0132] According to (11), even if a large amount of heating power is temporarily supplied to the heating element due to the suction operation, the first threshold is increased, so that the protection circuit can be operated appropriately.

[0133] (12) A power supply unit for the aerosol generating device according to any one of (3) to (11), The processor supplies power from the power source to the charging circuit, obtains the voltage of the charging circuit charged by that power, and adjusts the first threshold based on that voltage, or controls the discharging of the voltage of the charging circuit to obtain the voltage of the charging circuit, and adjusts the first threshold based on that voltage.

[0134] According to (12), the first threshold value can be adjusted according to individual differences in the charge circuit, so that the protection circuit can operate appropriately regardless of individual differences.

[0135] (13) A power supply unit for the aerosol generating device according to (1) or (2), The monitoring circuit is a power supply unit of an aerosol generating device that outputs a signal to activate the protection circuit based on the first time (elapsed time t3) from when the voltage of the charging circuit reaches the second threshold (threshold TH3) from the initial value (0V).

[0136] According to (13), when the supply of heating power is being performed appropriately, by setting the time threshold value so that the first time does not deviate significantly from the time threshold value, it becomes possible to determine whether the supply of heating power is being performed appropriately based on the relationship between the time threshold value and the first time, and the protection circuit can operate appropriately.

[0137] (14) A power supply unit for the aerosol generating device according to (13), The monitoring circuit outputs a signal to activate the protection circuit when the difference between the first time and a time threshold (threshold TH4) is equal to or greater than a difference threshold, a power supply unit of the aerosol generating device.

[0138] According to (14), the protection circuit can be operated appropriately.

[0139] (15) A power supply unit for the aerosol generating device according to (14), the processor controls the supply of the heating power to the heating element in accordance with a heating profile that defines a temperature transition of the heating element; A power supply unit of an aerosol generating device, wherein during the period in which the supply control is performed in accordance with the heating profile, the time threshold is variably controlled based on the heating profile.

[0140] According to (15), an appropriate time threshold is set according to the heating profile, so that the protection circuit can be activated appropriately.

[0141] (16) A power supply unit for the aerosol generating device according to (15), the heating profile includes a first period (temperature rise periods T1, T5) in which the gradient of the temperature transition is greater than a gradient threshold, and a second period (temperature maintenance periods T2, T4, T6) in which the gradient of the temperature transition is equal to or less than the gradient threshold, A power supply unit of an aerosol generating device, wherein the time threshold is set to a different value between the first period and the second period.

[0142] According to (16), an appropriate time threshold is set according to the heating profile, so that the protection circuit can be activated appropriately.

[0143] (17) A power supply unit for the aerosol generating device according to (16), A power supply unit of an aerosol generating device, wherein the time threshold set for the first period is smaller than the time threshold set for the second period.

[0144] According to (17), since more heating power is supplied to the heating element in the first period than in the second period, the time it takes for the voltage of the charging circuit to reach the second threshold is shorter. Therefore, by reducing the time threshold in the first period, the protection circuit can be operated appropriately.

[0145] (18) A power supply unit for the aerosol generating device according to (15), The heating profile includes a first period (temperature rise period T1) in which the gradient of the temperature transition is maximum, A power supply unit of an aerosol generating device, wherein the time threshold set for the first period is set to the minimum within the period during which the supply control is performed according to the heating profile.

[0146] According to (18), in the first period, a large amount of heating power is supplied to the heating element, so the time it takes for the voltage of the charging circuit to reach the second threshold is short. Therefore, by reducing the time threshold in this period, the protection circuit can be operated appropriately.

[0147] (19) A power supply unit for the aerosol generating device according to any one of (14) to (18), a suction sensor (suction sensor 15) that detects a suction operation by a user; A power supply unit of an aerosol generating device, wherein the time threshold is reduced when the inhalation action is detected.

[0148] According to (19), even if a large amount of heating power is temporarily supplied to the heating element due to the suction operation, the time threshold is reduced, so that the protection circuit can be operated appropriately.

[0149] (20) A power supply unit for the aerosol generating device according to any one of (14) to (19), The processor supplies power from the power source to the charging circuit, obtains the voltage of the charging circuit charged by that power, and adjusts the time threshold based on that voltage, or controls the discharge of the voltage of the charging circuit to obtain the voltage of the charging circuit, and adjusts the time threshold based on that voltage.

[0150] According to (20), the time threshold can be adjusted according to the individual differences of the charge circuit, so that the protection circuit can operate appropriately regardless of the individual differences.

[0151] (twenty one) A control method for a power supply unit of an aerosol generating device including a processor (MCU 11) that controls the supply of power from a power source (battery 12) to a heating element (heater 40 (reactor and susceptor in the case of induction heating)) for heating an aerosol source and / or a flavor source, a protection circuit (protection circuit 30) that limits the supply of the power to the heating element, and a charge circuit (resistance element 22 and capacitor 23) that can store power using the power, Discharge control is performed to discharge the voltage of the charge circuit (resistance element 22 and capacitor 23) at a timing (start timing of measurement period TD) based on a supply cycle (control cycle TC) of the power to the heating element, A control method for activating the protection circuit based on the voltage of the charging circuit. [Explanation of symbols]

[0152] 12 Battery (power supply) 20 Monitoring circuit 30 Protection circuit 110 Power Supply Unit 11 MCU (processor) TC control cycle (supply cycle)

Claims

1. Power supply and a processor for controlling the supply of heating power from the power source to a heating element for heating the aerosol source and / or the flavor source; a protection circuit that limits the supply of the heating power to the heating element; a monitoring circuit that includes a charging circuit capable of storing electricity using power from the power source when heating power is supplied from the power source to the heating element, and that outputs a signal to activate the protection circuit based on the voltage of the charging circuit; The processor performs discharge control to discharge the voltage of the charge circuit at a timing based on the supply cycle of the heating power to the heating element, in a power supply unit of an aerosol generating device.

2. A power supply unit for the aerosol generating device according to claim 1, A power supply unit for an aerosol generating device, wherein the timing is synchronized with the end timing of control of supplying the heating power to the heating element.

3. A power supply unit for the aerosol generating device according to claim 1 or 2, A power supply unit of an aerosol generating device, wherein the monitoring circuit outputs a signal to activate the protection circuit based on the result of comparing the voltage of the charging circuit with a first threshold value.

4. A power supply unit for the aerosol generating device according to claim 3, the voltage of the charging circuit charged by a single supply of the heating power to the heating element can be fully discharged by the discharge control; A power supply unit of an aerosol generating device, wherein the first threshold is greater than the maximum voltage of the charging circuit charged by a single supply of the heating power to the heating element.

5. A power supply unit for the aerosol generating device according to claim 3, A power supply unit for an aerosol generating device, wherein the voltage of the charging circuit charged by a single supply of the heating power to the heating element is greater than the voltage of the charging circuit discharged by the discharge control.

6. A power supply unit for the aerosol generating device according to claim 5, A power supply unit of an aerosol generating device, wherein the first threshold is a value reached by charging the charging circuit during a period in which the heating power is supplied to the heating element after charging and discharging of the charging circuit have been repeated multiple times.

7. A power supply unit for the aerosol generating device according to claim 5 or 6, the processor controls the supply of the heating power to the heating element in accordance with a heating profile that defines a temperature transition of the heating element; A power supply unit of an aerosol generating device, wherein the first threshold is variably controlled based on the heating profile during a period in which the supply control is performed in accordance with the heating profile.

8. A power supply unit for the aerosol generating device according to claim 7, the heating profile includes a first period during which the slope of the temperature transition is greater than a slope threshold and a second period during which the slope of the temperature transition is equal to or less than the slope threshold; A power supply unit of an aerosol generating device, wherein the first threshold is set to a different value between the first period and the second period.

9. A power supply unit for the aerosol generating device according to claim 8, A power supply unit of an aerosol generating device, wherein the first threshold set in the first period is greater than the first threshold set in the second period.

10. A power supply unit for the aerosol generating device according to claim 7, the heating profile includes a first period in which the gradient of the temperature transition is maximum; A power supply unit of an aerosol generating device, wherein the first threshold value set for the first period is set to the maximum value during the period in which the supply control is performed according to the heating profile.

11. A power supply unit for the aerosol generating device according to any one of claims 3 to 10, The processor supplies power from the power source to the charging circuit, obtains the voltage of the charging circuit charged by the power, and adjusts the first threshold based on the voltage, or controls the discharging of the voltage of the charging circuit to obtain the voltage of the charging circuit and adjusts the first threshold based on the voltage.

12. A power supply unit for the aerosol generating device according to claim 1 or 2, A power supply unit for an aerosol generating device, wherein the monitoring circuit outputs a signal to activate the protection circuit based on a first time period for the voltage of the charging circuit to reach a second threshold value from an initial value state.

13. A power supply unit for the aerosol generating device according to claim 12, A power supply unit of an aerosol generating device, wherein the monitoring circuit outputs a signal to activate the protection circuit when the difference between the first time and a time threshold is greater than or equal to a difference threshold.

14. A power supply unit for the aerosol generating device according to claim 13, the processor controls the supply of the heating power to the heating element in accordance with a heating profile that defines a temperature transition of the heating element; A power supply unit of an aerosol generating device, wherein during the period in which the supply control is performed in accordance with the heating profile, the time threshold is variably controlled based on the heating profile.

15. A method for controlling a power supply unit of an aerosol generating device, the method comprising: a processor that controls the supply of power from a power source to a heating element for heating an aerosol source and / or a flavor source; a protection circuit that limits the supply of the power to the heating element; and a charging circuit that can store power using the power, performing discharge control to discharge the voltage of the charge circuit at a timing based on a supply cycle of the power to the heating element; A control method for activating the protection circuit based on the voltage of the charging circuit.

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