Aerosol generation device

Abstract

An inhalation device (100) generates aerosol by heating an aerosol source by inductively heating a susceptor (Su) provided so as to be capable of heating the aerosol source. The inhalation device (100) comprises: a battery (10); a plurality of resonance circuits (80) provided in parallel to each other relative to the battery (10); a plurality of drive circuits (70) provided so as to correspond to the plurality of resonance circuits (80); and an MCU (30). At least one switching element (72) is provided between each resonance circuit (80) and a ground (GND) serving as a reference potential. When driving a drive circuit (70A) provided so as to correspond to a resonance circuit (80A) that is brought into a heating operation state, the MCU (30) controls the switching element (72) provided so as to correspond to a resonance circuit (80B) that is in a non-heating operation state.

Description

Aerosol Generator

[0001] The present disclosure relates to an aerosol generating device that inductively heats a susceptor that is provided to be able to heat an aerosol source.

[0002] Conventionally, there have been known aerosol generating devices that generate aerosols containing, for example, flavor components and allow a user to inhale the generated aerosols. Typically, such aerosol generating devices generate the aerosol by heating an aerosol source with a heating unit that is an electric resistance heater or an induction heater.

[0003] Patent Document 1 describes a circuit for a plurality of inductive elements (e.g., electromagnets, coils, or solenoids) for an aerosol generating device for inductively heating a susceptor for heating an aerosol-generating material. The circuit in Patent Document 1 includes a driver device configured to provide alternating current to each of the plurality of inductive elements in use.

[0004] Japanese Patent No. 6961894

[0005] In the circuit of Patent Document 1, when the driver device provides an AC current to one of the two induction elements, a first induction element, to inductively heat the susceptor, an induced current may be generated in the other induction element, a second induction element, in response to a magnetic field generated by the first induction element. If this induced current flows into the first induction element and interferes with it, the heating efficiency of the aerosol generation device may decrease.

[0006] The present disclosure provides an aerosol generating device that can improve the efficiency of heating by multiple resonant circuits that can inductively heat a susceptor.

[0007] The present disclosure provides an aerosol generating device that generates an aerosol by inductively heating a susceptor that is configured to be able to heat an aerosol source, the aerosol generating device comprising: a power source; a plurality of resonant circuits that are configured in parallel with the power source, each having a coil and a capacitor, and that generate a magnetic field from the coil to inductively heat the susceptor; a plurality of drive circuits that are configured corresponding to the plurality of resonant circuits, each converting DC power from the power source into AC power and supplying the AC power to the corresponding resonant circuit; and a control device that is configured to be able to control the plurality of drive circuits and selectively switches a resonant circuit among the plurality of resonant circuits to a first state in which power is supplied from the power source, wherein at least one switching element is provided between each resonant circuit and ground that serves as a reference potential; and when driving the drive circuit that is configured corresponding to the resonant circuit that is configured to be in the first state, the control device controls the switching element that is configured corresponding to the resonant circuit that is in a second state in which power is not supplied from the power source.

[0008] According to the present disclosure, it is possible to improve the efficiency of heating by a plurality of resonant circuits capable of inductively heating a susceptor.

[0009] FIG. 1 is a schematic diagram showing a first configuration example of the suction device 100. FIG. 2 is a schematic diagram showing a second configuration example of the suction device 100. FIG. 3 is a diagram showing a first example of the circuit configuration of the suction device 100. FIG. 4 is a diagram explaining the reverse flow of induced current generated in the resonant circuit 80B in the non-heating operating state. FIG. 5 is a diagram showing a state in which the second FET 72 provided corresponding to the resonant circuit 80B in the non-heating operating state is switched to a conductive state. FIG. 6 is a diagram showing a second example of the circuit configuration of the suction device 100. FIG. 7 is a diagram showing a third example of the circuit configuration of the suction device 100. FIG. 8 is a diagram showing a fourth example of the circuit configuration of the suction device 100.

[0010] Hereinafter, one embodiment of the aerosol generating device of the present disclosure will be described in detail with reference to the drawings. The drawings should be viewed in the direction of the reference symbols. Note that not all of the features described in the following embodiment are necessarily essential. Furthermore, two or more of the features described in the following embodiment can be arbitrarily combined. Hereinafter, identical or similar elements will be denoted by identical or similar reference symbols, and their description may be omitted or simplified as appropriate.

[0011] 1. Configuration Example of Inhalation Device An inhalation device, which is an example of an aerosol generating device according to the present disclosure, is a device that generates a substance to be inhaled by a user. In the following description, the substance generated by the inhalation device is described as an aerosol. Alternatively, the substance generated by the inhalation device may be a gas.

[0012] (1-1. First Configuration Example of Inhalation Device) FIG. 1 is a schematic diagram showing a first configuration example of an inhalation device 100. As shown in FIG. 1, the inhalation device 100A of this configuration example includes a power supply unit 110, a cartridge 120, and a flavor imparting cartridge 130. The power supply unit 110 includes a power supply section 111A, a sensor section 112A, a notification section 113A, a memory section 114A, a communication section 115A, and a control section 116A. The cartridge 120 includes a heating section 121A, a liquid guiding section 122, and a liquid storage section 123. The flavor imparting cartridge 130 includes a flavor source 131 and a mouthpiece 124. An air flow path 180 is formed in the cartridge 120 and the flavor imparting cartridge 130.

[0013] The power supply unit 111A stores power. The power supply unit 111A supplies power to each component of the suction device 100A under the control of the control unit 116A. The power supply unit 111A may be configured to be rechargeable with power received from an external power source. Examples of the external power source include an AC (Alternating Current) adapter, a mobile charger, and a PC (Personal Computer). The power supply unit 111A is implemented by a rechargeable battery such as a lithium-ion secondary battery.

[0014] The sensor unit 112A acquires various types of information related to the suction device 100A. The sensor unit 112A is configured with, for example, a pressure sensor such as a condenser microphone, a flow rate sensor, or a temperature sensor, and acquires values ​​associated with the suction by the user.

[0015] As one example, sensor unit 112A may include a pressure sensor (also referred to as a "puff sensor") that detects a change in pressure (hereinafter also referred to as an "internal pressure") inside suction device 100A caused by the user's inhalation. As another example, sensor unit 112A may include a flow rate sensor that detects a flow rate (hereinafter also simply referred to as a "flow rate") caused by the user's inhalation. As another example, sensor unit 112A may include a temperature sensor (also referred to as a "puff thermistor") that detects the temperature of heating unit 121A or the vicinity of heating unit 121A.

[0016] The sensor unit 112A may also include an operation detection unit that detects user operations. In other words, the sensor unit 112A may also function as an input unit that accepts information input from the user. In this case, the sensor unit 112A may be configured to include an operation button, an operation switch, a motion sensor, a hall sensor, or the like.

[0017] The notification unit 113A notifies the user of information. The notification unit 113A may be configured, for example, by a light-emitting device that emits light, a display device that displays images, a sound output device that outputs sound, or a vibration device that vibrates. Here, the light-emitting device may be realized, for example, by a light-emitting element such as an LED (Light-Emitting Diode). The display device may be, for example, a liquid crystal display or an OLED display (OLED: Organic Light Emitting Diode). The sound output device may be, for example, a speaker. The vibration device may be, for example, a vibrator configured to include a motor and an eccentric weight attached to the rotation shaft of the motor.

[0018] The storage unit 114A stores various types of information (for example, programs and data) for the operation of the suction device 100 A. The storage unit 114A may be configured, for example, by a non-volatile storage medium such as a flash memory.

[0019] 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), Bluetooth (registered trademark), BLE (Bluetooth Low Energy), NFC (Near Field Communication), or LPWA (Low Power Wide Area).

[0020] The control unit 116A functions as an arithmetic processing unit and a control unit, and controls the overall operation of the suction device 100A in accordance with programs stored in the memory unit 114A, etc. For example, the control unit 116A controls the supply of power from the power supply unit 111A to each component (e.g., the heating unit 121A described below) and the charging of the power supply unit 111A with power received from an external power source. The control unit 116A can be configured, for example, by an electronic circuit or the like including a CPU (Central Processing Unit) or a microprocessor (hereinafter also referred to as an "MCU (Micro Controller Unit)").

[0021] The liquid reservoir 123 stores an aerosol source. The aerosol source is atomized to generate an aerosol. The aerosol source is a liquid, such as a polyhydric alcohol, such as glycerin or propylene glycol, or water. The aerosol source may contain a tobacco-derived or non-tobacco-derived flavor component. When the inhalation device 100A is a medical inhaler, such as a nebulizer, the aerosol source may contain a drug.

[0022] The liquid guide portion 122 guides and holds the aerosol source, which is a liquid stored in the liquid storage portion 123, from the liquid storage portion 123. The liquid guide portion 122 is, for example, a wick formed by twisting a fiber material such as glass fiber or a porous material such as porous ceramic. In this case, the aerosol source stored in the liquid storage portion 123 is guided by the capillary effect of the wick.

[0023] The heating unit 121A generates an aerosol by, for example, heating the aerosol source to atomize the aerosol source. The heating unit 121A is configured in any shape, such as a coil, film, or blade, and is made of any material, such as metal or polyimide. In the example shown in FIG. 1 , the heating unit 121A is configured as a coil wound with a heating resistor, such as nichrome or stainless steel, and is wound around the liquid guiding unit 122. When the heating unit 121A generates heat, the aerosol source held in the liquid guiding unit 122 is heated and atomized, generating an aerosol. The heating unit 121A generates heat when power is supplied from the power supply unit 111A (hereinafter also referred to as "power supply").

[0024] As an example, power supply from power supply unit 111A to heating unit 121A may be performed when sensor unit 112A detects that the user has started inhaling and / or that predetermined information has been input. Then, when sensor unit 112A detects that the user has stopped inhaling and / or that predetermined information has been input, power supply to heating unit 121A may be stopped.

[0025] The heating unit 121A may be configured to generate aerosol by vibration or induction heating. When the aerosol is generated by vibration, the suction device 100A includes a vibration unit as the heating unit 121A. The vibration unit is configured, for example, by a plate-shaped member including piezoelectric ceramics that functions as an ultrasonic vibrator. When the vibration unit vibrates, the aerosol source guided to the surface of the vibration unit by the liquid guide unit 122 is atomized by ultrasonic waves generated by the vibration of the vibration unit, thereby generating the aerosol.

[0026] Furthermore, when aerosol generation is performed by induction heating, the suction device 100A includes a susceptor and an electromagnetic induction source as the heating unit 121A. The susceptor is made of a conductive material such as metal and generates heat through electromagnetic induction. The susceptor is disposed adjacent to the liquid guide unit 122. As an example, the susceptor is made of a metal conductor and is wound around the liquid guide unit 122. The electromagnetic induction source heats the susceptor through electromagnetic induction. The electromagnetic induction source is made of, for example, a coiled conductor and generates a magnetic field when an alternating current is supplied from the power supply unit 111A. When the magnetic field is generated, an eddy current is generated in the susceptor, generating Joule heat. The aerosol source held in the liquid guide unit 122 is heated and atomized by this Joule heat, generating the aerosol.

[0027] The flavor source 131 is a component for imparting flavor components to the aerosol. The flavor source 131 includes tobacco-derived or non-tobacco-derived flavor components. For example, the flavor source 131 may be a tobacco-derived product, such as a processed product obtained by molding shredded tobacco or tobacco raw materials into granules, sheets, or powder. The flavor source 131 may also include a non-tobacco-derived product made from plants other than tobacco (e.g., mint and herbs). For example, the flavor source 131 may include a flavor component such as menthol. The flavor source 131 may also be a stick-shaped member. When the inhalation device 100A is a medical inhaler, the flavor source 131 may include a medication for inhalation by the patient. Note that the flavor source 131 is not limited to a solid, but may also be a liquid containing flavor components such as polyhydric alcohols such as glycerin and propylene glycol, and water. The flavor source 131 may also be disposed inside a container such as a capsule.

[0028] The air flow path 180 is a path for air inhaled by the user. The air flow path 180 has a tubular structure with an air inlet 181, which is an entrance for air into the air flow path 180, and an air outlet 182, which is an exit for air from the air flow path 180, at both ends. A liquid guide section 122 is disposed on the upstream side (closer to the air inlet 181) of the air flow path 180, and a flavor source 131 is disposed on the downstream side (closer to the air outlet 182). Air flowing in through the air inlet 181 as the user inhales is mixed with the aerosol generated by the heating section 121A and, as shown by arrow 190, is transported through the flavor source 131 to the air outlet 182. When the mixed fluid of the aerosol and air passes through the flavor source 131, flavor components contained in the flavor source 131 are imparted to the aerosol.

[0029] Mouthpiece 124 is a member that is held in the mouth by the user when inhaling. Air outlet holes 182 are arranged in mouthpiece 124. By holding mouthpiece 124 in the mouth and inhaling, the user can take in the mixed fluid of the aerosol and air into the oral cavity.

[0030] The above describes an example of the configuration of the suction device 100A. Of course, the configuration of the suction device 100A is not limited to the above, and various configurations such as those exemplified below may be used.

[0031] As an example, the inhalation device 100A may not include the flavoring cartridge 130. In that case, the cartridge 120 is provided with the mouthpiece 124.

[0032] As another example, the inhalation device 100A may further include a flavor source heating unit (not shown) that heats the flavor source 131. The flavor source heating unit may be, for example, in the form of a film and arranged to cover the outer periphery of the flavor source 131. The flavor source heating unit generates heat when power is supplied from the power supply unit 111A, thereby heating the flavor source 131 from the outer periphery. The flavor source heating unit may be, for example, in the form of a blade that pierces the flavor source 131 and heats the flavor source 131 from the inside. The flavor source heating unit may also be configured to heat the flavor source 131 by vibration or induction heating. By providing such a flavor source heating unit, the temperature of the flavor source 131 can be increased compared to when a flavor source heating unit is not provided, thereby enabling an increase in the amount of flavor components imparted to the aerosol.

[0033] As another example, the inhalation device 100A may include multiple types of aerosol sources. Multiple types of aerosols generated from the multiple types of aerosol sources may be mixed in the air flow path 180 and undergo a chemical reaction to generate additional types of aerosols.

[0034] Furthermore, the means for atomizing the aerosol source is not limited to heating by the heating unit 121 A. For example, the means for atomizing the aerosol source may be vibration atomization or induction heating.

[0035] (1-2. Second Configuration Example of Suction Device) Fig. 2 is a schematic diagram showing a second configuration example of the suction device 100. As shown in Fig. 2, the suction device 100B of this configuration example includes a power supply unit 111B, a sensor unit 112B, a notification unit 113B, a memory unit 114B, a communication unit 115B, a control unit 116B, a heating unit 121B, a storage unit 140, and a heat insulating unit 144.

[0036] Each of the power supply unit 111B, sensor unit 112B, notification unit 113B, memory unit 114B, communication unit 115B, and control unit 116B is substantially the same as the corresponding component included in the suction device 100A described above.

[0037] 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 suction 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.

[0038] 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 inhalation device 100B 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.

[0039] 2, the heating unit 121B is configured as a film heater with conductive tracks made of heating resistors whose electrical resistance value correlates with temperature, and is arranged to cover the outer periphery of the housing unit 140. When the heating unit 121B generates heat, the substrate unit 151 of the stick-shaped substrate 150 is heated from the outer periphery, generating an aerosol. Note that the heating resistor of the heating unit 121B can be the same as the heating resistor of the heating unit 121A described above.

[0040] The heat insulating section 144 prevents heat transfer from the heating section 121B 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.

[0041] The above is a description of an example of the configuration of the suction device 100B. Of course, the configuration of the suction device 100B is not limited to the above, and various configurations such as those exemplified below may be used.

[0042] As one example, the heating unit 121B 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 121B 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 121B may be disposed so as to cover the bottom 143 of the storage unit 140. Furthermore, the heating unit 121B 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.

[0043] As another example, the accommodation 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 accommodation unit 140 may then open and close the outer shell to accommodate the stick-shaped substrate 150 inserted into the internal space 141 while clamping it. In this case, the heating unit 121B may be provided at the clamping location in the accommodation unit 140 and heat the stick-shaped substrate 150 while pressing it.

[0044] Furthermore, the means for atomizing the aerosol source is not limited to heating by the heating unit 121B. For example, the means for atomizing the aerosol source may be induction heating. In that case, the suction device 100B has at least an electromagnetic induction source such as a coil that generates a magnetic field, instead of the heating unit 121B. A susceptor that generates heat by induction heating may be provided in the suction device 100B, or may be included in the stick-shaped substrate 150.

[0045] Furthermore, the suction device 100B may further include the heating unit 121A, the liquid guide unit 122, the liquid storage unit 123, and the air flow path 180 according to the first configuration example, and the air flow path 180 may supply air to the internal space 141. In this case, the mixed fluid of the aerosol and air generated by the heating unit 121A flows into the internal space 141 and is further mixed with the aerosol generated by the heating unit 121B, and reaches the oral cavity of the user.

[0046] In the following description, the suction device 100A and the suction device 100B will be referred to as the "suction device 100" without distinction. Similarly, the power supply unit 111A and the power supply unit 111B may be referred to as the "power supply unit 111," the sensor unit 112A and the sensor unit 112B as the "sensor unit 112," the notification unit 113A and the notification unit 113B as the "notification unit 113," the memory unit 114A and the memory unit 114B as the "memory unit 114," the communication unit 115A and the communication unit 115B as the "communication unit 115," the control unit 116A and the control unit 116B as the "control unit 116," and the heating unit 121A and the heating unit 121B as the "heating unit 121."

[0047] 2. Circuit Configuration of Suction Device Next, the circuit configuration of the suction device 100 will be described.

[0048] (2-1. First Example of Circuit Configuration of Suction Device) FIG. 3 is a diagram showing a first example of the circuit configuration of the suction device 100. The example shown in FIG. 3 is an example in which the suction device 100 is the suction device 100B shown in FIG. 2, and aerosol is generated by induction heating a susceptor Su that is provided so as to be able to heat an aerosol source. Here, the susceptor Su is realized, for example, by a plate- or rod-shaped metal that extends along the longitudinal direction of the stick-shaped substrate 150 and is arranged inside the stick-shaped substrate 150 (more specifically, inside the substrate portion 151). Furthermore, the susceptor Su may be realized, for example, by a metal that is arranged so as to cover at least a portion of the outer periphery of the accommodation portion 140.

[0049] 3, the suction device 100 includes, for example, a battery 10 which is an example of a power supply unit 111, an LDO 20 (Low Drop Out), an MCU 30 which is an example of a control unit 116, a first DC / DC converter 40 (DC: Direct Current), a second DC / DC converter 50, a gate driver 60, a drive circuit 70, and a resonance circuit 80. As will be described in detail later, two of each of the gate driver 60, drive circuit 70, and resonance circuit 80 are provided.

[0050] Here, the MCU 30, the first DC / DC converter 40, the second DC / DC converter 50, and the gate driver 60 are each realized by an integrated circuit (IC) that integrates a plurality of electronic components, such as resistors, capacitors, and transistors. Furthermore, the ground terminals (e.g., low-potential power supply terminals) of the ICs that realize the MCU 30, the first DC / DC converter 40, the second DC / DC converter 50, and the gate driver 60 are electrically connected (hereinafter simply referred to as "connected") to a ground GND having a predetermined reference potential. This allows the MCU 30, the first DC / DC converter 40, the second DC / DC converter 50, and the gate driver 60 to operate based on the reference potential of the ground GND (in other words, a common reference potential), and the reference potential of the ground GND can be treated as 0 V, for example.

[0051] The battery 10 is a DC power supply that outputs a predetermined voltage, and is realized by, for example, a lithium-ion secondary battery. Hereinafter, the output voltage of the battery 10 will also be referred to as the "battery voltage Vbat." The battery voltage Vbat can be set to, for example, 3.5 to 4.0 V. The battery 10 is connected to each of the LDO 20, the first DC / DC converter 40, and the second DC / DC converter 50, and supplies the battery voltage Vbat to them.

[0052] The LDO regulator 20 is a linear regulator that receives the battery voltage Vbat, generates a constant voltage lower than the battery voltage Vbat, and outputs the generated constant voltage. Hereinafter, the output voltage of the LDO regulator 20 will also be referred to as the "first system voltage Vsys1." The first system voltage Vsys1 may be, for example, 3.3 V, which is suitable as a power supply voltage for the MCU 30. The LDO regulator 20 is connected to the MCU 30 and supplies the first system voltage Vsys1 to the MCU 30. This allows a stable first system voltage Vsys1 to be supplied to the MCU 30, thereby stabilizing the operation of the MCU 30.

[0053] Note that a step-up / step-down circuit (e.g., a step-up / step-down DC / DC converter) may be provided instead of the LDO regulator 20. In this case, the step-up / step-down circuit generates the first system voltage Vsys1 by boosting the battery voltage Vbat if the supplied battery voltage Vbat is lower than a voltage (e.g., 3.3 V) suitable for use as a power supply voltage for the MCU 30. On the other hand, the step-up / step-down circuit generates the first system voltage Vsys1 by lowering the battery voltage Vbat if the battery voltage Vbat is higher than the suitable power supply voltage for the MCU 30. In this way, an appropriate first system voltage Vsys1 can be supplied to the MCU 30, regardless of whether the battery voltage Vbat is higher or lower than the suitable power supply voltage for the MCU 30, thereby stabilizing the operation of the MCU 30.

[0054] The MCU 30 is a controller (i.e., a computer) that operates when the first system voltage Vsys1 is supplied as a power supply voltage and performs predetermined processing. As will be described in detail later, the MCU 30 can perform processing such as outputting a predetermined control signal (i.e., an instruction) to a gate driver 60 that drives a switch included in a drive circuit 70, which will be described later, as an example of processing for controlling the power supplied to the resonant circuit 80.

[0055] The first DC / DC converter 40 is a switching regulator that receives the battery voltage Vbat, generates a predetermined voltage different from the battery voltage Vbat, and outputs the generated predetermined voltage. The first DC / DC converter 40 may be used in combination with a power inductor (not shown). Hereinafter, the output voltage of the first DC / DC converter 40 is also referred to as the "power system voltage Vheat."

[0056] The first DC / DC converter 40 is connected to a drive circuit 70 that supplies power to a resonant circuit 80, and supplies a power system voltage Vheat to the connected drive circuit 70 or the resonant circuit 80. For example, as shown in FIG. 3 , when the first DC / DC converter 40 is connected to the drive circuit 70, the first DC / DC converter 40 supplies the power system voltage Vheat to the drive circuit 70.

[0057] The first DC / DC converter 40 generates a stable (for example, constant) power system voltage Vheat from the battery voltage Vbat, which may fluctuate depending on the remaining charge of the battery 10, and outputs the power system voltage Vheat. As a result, even if the battery voltage Vbat fluctuates, the stable power system voltage Vheat can be supplied to the resonant circuit 80, and the resonant circuit 80 can appropriately perform induction heating of the susceptor Su.

[0058] As an example, the first DC / DC converter 40 generates a power system voltage Vheat having a voltage value higher than the battery voltage Vbat by boosting the supplied battery voltage Vbat. In this case, the power system voltage Vheat may be set to, for example, 5.0 V. In this way, when the power system voltage Vheat is set higher than the battery voltage Vbat, the temperature of the susceptor Su can be increased more quickly than when the power system voltage Vheat is set lower than the battery voltage Vbat.

[0059] As another example, the first DC / DC converter 40 may generate a power system voltage Vheat having a voltage value lower than the battery voltage Vbat by stepping down the supplied battery voltage Vbat. In this case, the power system voltage Vheat may be set to, for example, 3.0 V. In this manner, when the power system voltage Vheat is set lower than the battery voltage Vbat, it is possible to reduce the power consumption by the resonant circuit 80 when inductively heating the susceptor Su compared to when the power system voltage Vheat is set higher than the battery voltage Vbat.

[0060] The second DC / DC converter 50 is a switching regulator that receives the battery voltage Vbat, generates a predetermined voltage different from the battery voltage Vbat, and outputs the generated predetermined voltage. The second DC / DC converter 50 may be used in combination with a power inductor (not shown). Hereinafter, the output voltage of the second DC / DC converter 50 will also be referred to as a "second system voltage Vsys2." The second DC / DC converter 50 is connected to the gate driver 60, and supplies the second system voltage Vsys2 to the gate driver 60.

[0061] The second DC / DC converter 50 generates a stable second system voltage Vsys2 from the fluctuating battery voltage Vbat, similar to the first DC / DC converter 40, and outputs the second system voltage Vsys2. As a result, even if the battery voltage Vbat fluctuates, the stable second system voltage Vsys2 can be supplied to the gate driver 60, allowing the gate driver 60 to operate appropriately.

[0062] As an example, the second DC / DC converter 50 boosts the supplied battery voltage Vbat to generate a second system voltage Vsys2 having a voltage value higher than the battery voltage Vbat. In this case, the second system voltage Vsys2 may be set to, for example, 5.8 V, which is suitable as a power supply voltage for the gate driver 60. However, the present invention is not limited to this, and the second DC / DC converter 50 may also generate a second system voltage Vsys2 having a voltage value lower than the battery voltage Vbat.

[0063] The gate driver 60 is an IC that drives a switch included in the drive circuit 70 based on an instruction (in other words, a control signal) from the MCU 30. Here, the switch included in the drive circuit 70 is a switch that turns on and off the power supply to the resonant circuit 80. In other words, the drive circuit 70 is a circuit that has a switch that turns on and off the power supply to the resonant circuit 80 based on an instruction from the MCU 30.

[0064] 3, the drive circuit 70 is configured as a half-bridge inverter circuit having a first FET (FET: Field Effect Transistor) 71 as a high-side switch and a second FET 72 as a low-side switch. Here, the first FET 71 and the second FET 72 are described as N-channel MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors), but they may be other types of switching elements (for example, P-channel MOSFETs).

[0065] The first FET 71, which is a high-side switch, has a drain terminal connected to the first DC / DC converter 40 and a source terminal connected to the drain terminal of the second FET 72. The source terminal of the second FET 72, which is a low-side switch, is connected to ground GND. The gate terminals of the first FET 71 and the second FET 72 are each connected to the gate driver 60. In addition, a connection point 70a, which is connected to the resonant circuit 80, is provided between the first FET 71 (more specifically, the source terminal of the first FET 71) and the second FET 72 (more specifically, the drain terminal of the second FET 72) in the drive circuit 70.

[0066] In the example shown in Figure 3, the MCU 30 is configured to be able to independently output to the gate driver 60, for example, a control signal as an instruction regarding the switching of the first FET 71 and a control signal as an instruction regarding the switching of the second FET 72. The MCU 30 then instructs the gate driver 60 to, for example, alternately place the first FET 71 and the second FET 72 in a conductive state. In accordance with this instruction, the gate driver 60 controls the gate voltages applied to the gate terminals of the first FET 71 and the second FET 72, thereby driving the first FET 71 and the second FET 72 so that the first FET 71 and the second FET 72 alternately place the first FET 71 and the second FET 72 in a conductive state. As a result, in the example shown in Figure 3, the drive circuit 70 configured as an inverter circuit converts DC power supplied from the battery 10 and the first DC / DC converter 40 into AC power, and this AC power can be supplied to the resonant circuit 80.

[0067] The resonant circuit 80 is a circuit that inductively heats the susceptor Su when power is supplied to it. That is, when power is supplied to the resonant circuit 80, it functions as an electromagnetic induction source and causes the susceptor Su to generate heat through electromagnetic induction.

[0068] For example, as shown in Fig. 3, the resonant circuit 80 has a resonant coil 81 and a resonant capacitor 82, which are connected in series to form an LC series resonant circuit. In this case, the resonant coil 81 is realized by, for example, a coil-shaped (e.g., spiral) conductor wound around the outer periphery of the housing portion 140, and generates a magnetic field when an alternating current is supplied. When the magnetic field is generated, an eddy current is generated in the susceptor Su, generating Joule heat. This Joule heat heats the aerosol source of the stick-shaped substrate 150, generating an aerosol.

[0069] The resonant capacitor 82 has one end connected to the resonant coil 81 and the other end connected to the ground GND. The resonant frequency varies depending on the inductance of the resonant coil 81 and the capacitance of the resonant capacitor 82, which constitute the resonant circuit 80.

[0070] In this embodiment, two gate drivers 60, two drive circuits 70, and two resonant circuits 80 are provided. The two resonant circuits 80 are provided in parallel with each other relative to the battery 10 and the first DC / DC converter 40. The two drive circuits 70 are provided corresponding to the two resonant circuits 80, respectively. The two gate drivers 60 are provided in parallel with each other relative to the second DC / DC converter 50, and are provided corresponding to the two drive circuits 70, respectively.

[0071] In the following description, the two gate drivers 60, the two drive circuits 70, and the two resonant circuits 80 may be distinguished and described by assigning the reference symbols gate drivers 60A, 60B, drive circuits 70A, 70B, and resonant circuits 80A, 80B, respectively.

[0072] The resonant coils 81A and 81B of the resonant circuits 80A and 80B are wound, for example, at different positions on the outer periphery of the accommodation portion 140, and the susceptor Su is induction heated by the two resonant circuits 80A and 80B. Note that, although the susceptor Su is common to the resonant coils 81A and 81B in the example shown in Fig. 3, separate susceptors Su may be provided for the resonant coils 81A and 81B, respectively.

[0073] The MCU 30 is configured to control the drive circuits 70A, 70B to selectively switch one of the two resonant circuits 80A, 80B to a heating operation state. Here, the "heating operation state" refers to a state in which AC power generated by driving the drive circuit 70 is supplied to the resonant circuit 80, and the resonant circuit 80 inductively heats the susceptor Su. Furthermore, a "non-heating operation state" described later refers to a state in which the drive circuit 70 is not driven, power is not supplied from the battery 10 to the resonant circuit 80, and the resonant circuit 80 does not inductively heat the susceptor Su.

[0074] Specifically, when induction heating the susceptor Su using the resonant circuit 80A, the MCU 30 drives the drive circuit 70A via the gate driver 60A, switching the resonant circuit 80A to a heating operation state. The MCU 30 also does not drive the drive circuit 70B, switching the resonant circuit 80B to a non-heating operation state. Conversely, when induction heating the susceptor Su using the resonant circuit 80B, the MCU 30 drives the drive circuit 70B via the gate driver 60B, switching the resonant circuit 80B to a heating operation state. The MCU 30 also does not drive the drive circuit 70A, switching the resonant circuit 80A to a non-heating operation state. When induction heating the susceptor Su using both the resonant circuit 80A and the resonant circuit 80B, the MCU 30 alternately switches the drive circuits 70A and 70B to be driven at predetermined time intervals, thereby alternately switching the resonant circuits 80A and 80B to be in a heating operation state at predetermined time intervals.

[0075] In this way, the inhalation device 100 includes two resonant circuits 80A and 80B, and therefore, different positions on the stick-shaped substrate 150, which is the aerosol source, can be selectively heated.

[0076] Consider the case shown in FIG. 4 where the drive circuit 70A is driven to inductively heat the susceptor Su using the resonant circuit 80A, but the drive circuit 70B is not driven (i.e., the first FET 71 and the second FET 72 of the drive circuit 70B are not conductive). In this case, the resonant coil 81B is electromagnetically induced in response to the magnetic field generated by the resonant coil 81A, and an induced current (indicated by a thick dashed arrow) may flow through the resonant circuit 80B. More specifically, induced currents I1 and I2 flow alternately in opposite directions through the resonant circuit 80B. The induced current I1 flows through a loop circuit formed between the resonant circuit 80B and the body diode (not shown) of the second FET 72 of the drive circuit 70B via ground GND. The induced current I2 flows back from the resonant circuit 80B through the body diode (not shown) of the first FET 71 of the drive circuit 70B toward the resonant circuit 80A. If the induced current I2 interferes with the resonant circuit 80A, the circuit impedance increases, and the current flowing through the resonant circuit 80A may decrease, which may reduce the heating efficiency of the resonant circuit 80A in the heating operation state.

[0077] 5, when the MCU 30 drives the drive circuit 70A provided corresponding to the resonant circuit 80A in the heating operation state, the MCU 30 switches the second FET 72 provided corresponding to the resonant circuit 80B in the non-heating operation state to a conductive state (denoted as "ON" in FIG. 5) via the gate driver 60B. That is, while the resonant circuit 80B is in the non-heating operation state, the MCU 30 does not drive the drive circuit 70B, but rather sets the first FET 71 to a non-conductive state and the second FET 72 to a conductive state, rather than setting both the first FET 71 and the second FET 72 to a non-conductive state. The second FET 72 is a switching element provided between the resonant circuit 80B and ground GND. When the second FET 72 is in the conductive state, the resonant circuit 80B and the second FET 72 form a loop circuit via ground GND.

[0078] The induced current generated in the resonant circuit 80B flows in a loop within the loop circuit and does not flow back through the body diode of the first FET 71. This prevents the induced current generated in the resonant circuit 80B in the non-heating operating state from flowing back to the resonant circuit 80A in the heating operating state and interfering with the resonant circuit 80A, thereby improving the heating efficiency of the resonant circuit 80A in the heating operating state. Furthermore, unlike the second to fourth examples described below, the first example does not require the addition of a new switching element to prevent the induced current from flowing back, thereby reducing the number of components.

[0079] (2-2. Second Example of Circuit Configuration of Suction Device) Figure 6 is a diagram showing a second example of the circuit configuration of the suction device 100. In the circuit configuration of the second example, switching elements 91A and 91B (denoted as "FET" in the figure) are further provided in addition to the circuit configuration of the first example described above.

[0080] The switching elements 91A, 91B are provided between the resonant capacitor 82 of each resonant circuit 80A, 80B and ground GND. The switching elements 91A, 91B are, for example, N-channel MOSFETs, with drain terminals connected to the resonant capacitor 82 and source terminals connected to ground GND. The gate terminals of the switching elements 91A, 91B are connected to a gate driver (not shown), and the MCU 30 outputs a switching instruction to switch the switching elements 91A, 91B between a conductive state and a non-conductive state via the gate driver.

[0081] When driving the drive circuit 70A provided corresponding to the resonant circuit 80A in the heating operation state, the MCU 30 switches the switching element 91B provided corresponding to the resonant circuit 80B in the non-heating operation state to a non-conductive state ("OFF" in FIG. 6). In the second example, the first FET 71 and the second FET 72 of the drive circuit 70B are both non-conductive. The MCU 30 also switches the switching element 91A provided corresponding to the resonant circuit 80A in the heating operation state to a conductive state ("ON" in the figure).

[0082] 4 is not formed in the resonant circuit 80B in the non-heating operating state, and no induced current is generated in the resonant circuit 80B. Therefore, no induced current flows back from the resonant circuit 80B in the non-heating operating state to the resonant circuit 80A in the heating operating state, improving the heating efficiency of the resonant circuit 80A in the heating operating state.

[0083] Furthermore, since the switching element 91A is switched to the conductive state, the resonant circuit 80A functions normally in the heating operation state, and the susceptor Su can be induction-heated.

[0084] (2-3. Third Example of Circuit Configuration of Suction Device) Figure 7 is a diagram showing a third example of the circuit configuration of the suction device 100. The circuit configuration of the third example further includes diodes 92A, 92B and switching elements 93A, 93B (denoted as "FET" in the figure) in addition to the circuit configuration of the first example described above.

[0085] The diodes 92A and 92B are rectifying elements provided between the respective resonant circuits 80A and 80B and the ground GND. The anode terminals of the diodes 92A and 92B are connected to the connection point 80a between the resonant coil 81 and the resonant capacitor 82, and the cathode terminals are connected to the switching elements 93A and 93B.

[0086] The switching elements 93A and 93B are, for example, N-channel MOSFETs, with drain terminals connected to the cathode terminals of the diodes 92A and 92B and source terminals connected to ground GND. The gate terminals of the switching elements 93A and 93B are connected to a gate driver (not shown), and the MCU 30 outputs a switching instruction for switching the switching elements 93A and 93B between a conductive state and a non-conductive state via the gate driver. Note that the switching elements 93A and 93B are not limited to N-channel MOSFETs and may be other types of switching elements.

[0087] In this way, the diodes 92A and 92B and the switching elements 93A and 93B are provided in parallel with the resonant capacitor 82 relative to the resonant coil 81.

[0088] When driving the drive circuit 70A provided corresponding to the resonant circuit 80A in the heating operation state, the MCU 30 switches the switching element 93B provided corresponding to the resonant circuit 80B in the non-heating operation state to the conductive state ("ON" in the figure). In the third example, as in the second example, the first FET 71 and the second FET 72 of the drive circuit 70B are both in the non-conductive state. Furthermore, the MCU 30 switches the switching element 93A provided corresponding to the resonant circuit 80A in the heating operation state to the non-conductive state ("OFF" in the figure).

[0089] Because the switching element 93B is switched to the conductive state, the induced current (indicated by the thick dashed arrow) generated in the resonant circuit 80B in the non-heating operating state flows to ground GND through the diode 92B and the switching element 93B. The resonant circuit 80B does not resonate. This prevents the induced current generated in the resonant circuit 80B in the non-heating operating state from flowing back to the resonant circuit 80A, improving the heating efficiency of the resonant circuit 80A in the heating operating state.

[0090] Furthermore, since the switching element 93A is switched to the non-conductive state, no current flows through the diode 92A and the switching element 93A, and the resonant circuit 80A functions normally in the heating operation state, thereby enabling induction heating of the susceptor Su.

[0091] (2-4. Fourth Example of Circuit Configuration of Suction Device) Figure 8 is a diagram showing a fourth example of the circuit configuration of suction device 100. In the circuit configuration of the fourth example, the diodes 92A and 92B in the circuit configuration of the third example described above are replaced with switching elements 95A and 95B (denoted as "FET" in the figure). Note that, for the sake of explanation, Figure 8 illustrates the body diodes of switching elements 93A and 93B and switching elements 95A and 95B, respectively.

[0092] The switching elements 93A, 93B and the switching elements 95A, 95B are provided between the respective resonant circuits 80A, 80B and the ground GND, and are provided in parallel with the resonant capacitor 82 with respect to the resonant coil 81. The configuration of the switching elements 93A, 93B is the same as that of the third example, and therefore a description thereof will be omitted.

[0093] The switching elements 95A and 95B are, for example, N-channel MOSFETs, with drain terminals connected to the drain terminals of the switching elements 93A and 93B and source terminals connected to a connection point 80a between the resonant coil 81 and the resonant capacitor 82. With this connection, the body diodes of the switching elements 95A and 95B are formed so that the anode terminals are connected to the resonant circuits 80A and 80B and the cathode terminals are connected to the switching elements 93A and 93B. The body diodes of the switching elements 93A and 93B are also formed so that the anode terminals are connected to ground GND and the cathode terminals are connected to the switching elements 95A and 95B. Thus, the body diodes formed in the switching elements 95A and 95B and the body diodes formed in the switching elements 93A and 93B are arranged in opposite directions.

[0094] The gate terminals of the switching elements 95A and 95B are connected to a gate driver (not shown), and the MCU 30 outputs a switching instruction to switch the switching elements 95A and 95B between a conductive state and a non-conductive state via the gate driver.

[0095] When driving the drive circuit 70A provided corresponding to the resonant circuit 80A in the heating operation state, the MCU 30 switches the switching element 93B and the switching element 95B provided corresponding to the resonant circuit 80B in the non-heating operation state to the conductive state ("ON" in the figure). In the fourth example, as in the second and third examples, the first FET 71 and the second FET 72 of the drive circuit 70B are both in the non-conductive state. Furthermore, the MCU 30 switches the switching element 93A and the switching element 95A provided corresponding to the resonant circuit 80A in the heating operation state to the non-conductive state ("OFF" in the figure).

[0096] Because switching elements 93B and 95B are switched to the conductive state, the induced current (indicated by the thick dashed arrow) generated in resonant circuit 80B in the non-heating operating state flows to ground GND through switching elements 93B and 95B. Furthermore, resonant circuit 80B does not resonate. Therefore, the induced current generated in resonant circuit 80B in the non-heating operating state is prevented from flowing back to resonant circuit 80A, thereby improving the heating efficiency of the aerosol source.

[0097] Furthermore, since the switching elements 93A and 95A are switched to a non-conducting state, no current flows through the switching elements 93A and 95A, and the resonant circuit 80A functions normally in a heating operation state, thereby enabling induction heating of the susceptor Su.

[0098] As described above in the first to fourth examples of the circuit configuration of the suction device 100, at least one switching element (second FET 72, switching elements 91A, 91B, 93A, 93B, 95A, 95B) is provided between each resonant circuit 80 and ground GND. When driving the drive circuit 70A provided corresponding to the resonant circuit 80A in the heating state, the MCU 30 controls the switching elements (second FET 72, switching elements 91B, 93B, 95B) provided corresponding to the resonant circuit 80B in the non-heating state. This configuration prevents the induced current generated in the resonant circuit 80B in the non-heating state from flowing back to the resonant circuit 80A, thereby improving the heating efficiency of the resonant circuit 80A in the heating state.

[0099] The timing at which the MCU 30 controls the switching element provided corresponding to the resonant circuit 80B in the non-heating operating state, specifically the timing at which the switching element is switched between the conductive state and the non-conductive state, can be set arbitrarily. For example, the MCU 30 may control the switching element provided corresponding to the resonant circuit 80B at the same time as switching the drive circuit 70A to the heating operating state, or may control the switching element provided corresponding to the resonant circuit 80B after switching the drive circuit 70A to the heating operating state.

[0100] While one embodiment of the present disclosure has been described above with reference to the drawings, it goes without saying that the present disclosure is not limited to such an embodiment. It is clear that a person skilled in the art can conceive of various modifications or alterations within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present disclosure. Furthermore, the components of the above-described embodiment may be combined in any manner without departing from the spirit of the invention.

[0101] For example, the circuit configuration of the suction device 100 in the above-described embodiment has been described assuming that the suction device 100 is the suction device 100B, but the suction device 100 may be the suction device 100A.

[0102] In the above-described embodiment, two gate drivers 60, two drive circuits 70, and two resonant circuits 80 are provided, but three or more of each may be provided.

[0103] This specification etc. describes at least the following items. In parentheses, components etc. corresponding to the above-mentioned embodiment are shown as examples, but the present invention is not limited to these.

[0104] (1) An aerosol generating device (suction device 100) that generates an aerosol by inductively heating a susceptor (susceptor Su) that is provided so as to be able to heat an aerosol source, the aerosol generating device comprising: a power source (battery 10 and a first DC / DC converter 40); a plurality of resonant circuits (resonant circuits 80 (80A, 80B)) that are provided in parallel with the power source, each having a coil (resonant coil 81) and a capacitor (resonant capacitor 82), and that generate a magnetic field from the coil to inductively heat the susceptor; a plurality of drive circuits (drive circuits 70 (70A, 70B)) that are provided corresponding to the plurality of resonant circuits, respectively, and that convert DC power from the power source into AC power and supply the AC power to the corresponding resonant circuits; and a control device (MCU 30) that is provided so as to be able to control the plurality of drive circuits and that selectively switches among the plurality of resonant circuits which resonant circuits to a first state (heating operation state) in which power is supplied from the power source. An aerosol generating device, wherein at least one switching element (second FET 72, switching elements 91A, 91B, 93A, 93B, 95A, 95B) is provided between each resonant circuit and ground (ground GND) which serves as a reference potential, and the control device controls the switching element provided corresponding to the resonant circuit in a second state in which no power is supplied from the power source when driving the drive circuit provided corresponding to the resonant circuit to be set to the first state.

[0105] According to (1), since the switching element provided corresponding to the resonant circuit in the second state is controlled, it is possible to prevent the induced current generated in the resonant circuit in the second state from flowing back to other resonant circuits, thereby improving the efficiency of heating by the resonant circuit in the first state.

[0106] (2) The aerosol generating device according to (1), wherein each drive circuit has a high-side switch (first FET 71), a low-side switch (second FET 72) connected to the ground, and a connection point (connection point 70a) provided between the high-side switch and the low-side switch and connected to the corresponding resonant circuit, the switching element includes the low-side switch, and the control device switches the low-side switch provided corresponding to the resonant circuit in the second state to a conductive state when driving the drive circuit provided corresponding to the resonant circuit to be set to the first state.

[0107] According to (2), by switching the low-side switch provided corresponding to the resonant circuit in the second state to the conductive state, a loop circuit can be formed in which an induced current flows in a loop between the resonant circuit in the second state and the switching element via the ground. This prevents the induced current generated in the resonant circuit in the second state from flowing back into other resonant circuits. Furthermore, by using the low-side switch of the drive circuit as a switching element for preventing backflow, the number of components can be reduced.

[0108] (3) The aerosol generating device according to (1), wherein the switching elements (switching elements 91A, 91B) are provided between the capacitor and the ground, and when the control device drives the drive circuit provided corresponding to the resonant circuit in the first state, the control device switches the switching element provided corresponding to the resonant circuit in the second state to a non-conductive state.

[0109] According to (3), since the switching element provided between the capacitor and the ground is switched to the non-conducting state, no induced current is generated in the resonant circuit in the second state, and therefore, it is possible to prevent the induced current generated in the resonant circuit in the second state from flowing back to other resonant circuits.

[0110] (4) The aerosol generating device according to (1), wherein a rectifying element (diode 92A, 92B) and a switching element (switching element 93A, 93B) are provided in parallel with the capacitor for the coil between each resonant circuit and the ground, and when the control device drives the drive circuit provided corresponding to the resonant circuit to be set to the first state, the control device switches the switching element provided corresponding to the resonant circuit in the second state to a conductive state.

[0111] According to (4), the induced current generated in the resonant circuit in the second state flows to the ground through the rectifying element and the switching element, thereby preventing the induced current generated in the resonant circuit in the second state from flowing back to other resonant circuits.

[0112] (5) The aerosol generating device according to (1), wherein the switching elements are arranged in parallel with the capacitor relative to the coil between each resonant circuit and the ground, the switching elements have first switching elements (switching elements 95A, 95B) and second switching elements (switching elements 93A, 93B) connected in series, the body diodes formed in the first switching elements and the body diodes formed in the second switching elements are in opposite directions to each other, and when driving the drive circuit provided corresponding to the resonant circuit to be set to the first state, the control device switches the first switching elements and the second switching elements provided corresponding to the resonant circuit in the second state to a conductive state.

[0113] According to (5), the induced current generated in the resonant circuit in the second state flows to the ground through the first switching element and the second switching element, thereby preventing the induced current generated in the resonant circuit in the second state from flowing back to other resonant circuits.

[0114] (6) An aerosol generating device according to (1), wherein, when the switching element is in a conductive state, the resonant circuit and the switching element form a loop circuit through which an induced current generated in the resonant circuit flows in a loop via the ground, and when the control device drives the drive circuit provided corresponding to the resonant circuit to be in the first state, the control device switches the switching element provided corresponding to the resonant circuit in the second state to the conductive state.

[0115] According to (6), by switching the switching element provided corresponding to the resonant circuit in the second state to a conductive state, the resonant circuit and the switching element form a loop circuit via the ground, thereby preventing the induced current generated in the resonant circuit in the second state from flowing back into other resonant circuits.

[0116] 10 Battery (power supply) 30 MCU (control device) 40 First DC / DC converter (power supply) 70, 70A, 70B Drive circuit 70a Connection point 71 First FET (high side switch) 72 Second FET (low side switch, switching element) 80, 80A, 80B Resonant circuit 81 Resonant coil (coil) 82 Resonant capacitor (capacitor) 91A, 91B Switching element 92A, 92B Diode (rectifying element) 93A, 93B Switching element 95A, 95B Switching element 100 Suction device (aerosol generating device) GND Ground Su Susceptor

Claims

1. An aerosol generation device that generates an aerosol by inductively heating a susceptor that is provided so as to be able to heat an aerosol source, the aerosol generation device comprising: a power source; a plurality of resonant circuits that are provided in parallel with the power source and have a coil and a capacitor, the resonant circuits having a magnetic field generated from the coil to inductively heat the susceptor; a plurality of drive circuits that are provided corresponding to the plurality of resonant circuits and convert DC power from the power source into AC power and supply the AC power to the corresponding resonant circuits; and a control device that is provided to be able to control the plurality of drive circuits and selectively switches a resonant circuit among the plurality of resonant circuits to a first state in which power is supplied from the power source, wherein at least one switching element is provided between each resonant circuit and ground that serves as a reference potential; and the control device controls the switching element provided corresponding to a resonant circuit that is in a second state in which power is not supplied from the power source when driving the drive circuit provided corresponding to the resonant circuit that is to be set to the first state.

2. An aerosol generating device as described in claim 1, wherein each drive circuit has a high-side switch, a low-side switch connected to the ground, and a connection point provided between the high-side switch and the low-side switch and connected to the corresponding resonant circuit, the switching element includes the low-side switch, and when the control device drives the drive circuit provided corresponding to the resonant circuit to be set to the first state, it switches the low-side switch provided corresponding to the resonant circuit in the second state to a conductive state.

3. An aerosol generating device as described in claim 1, wherein the switching element is provided between the capacitor and the ground, and when the control device drives the drive circuit provided corresponding to the resonant circuit in the first state, it switches the switching element provided corresponding to the resonant circuit in the second state to a non-conducting state.

4. An aerosol generating device as described in claim 1, wherein a rectifying element and a switching element are provided in parallel with the capacitor for the coil between each resonant circuit and the ground, and when the control device drives the drive circuit provided corresponding to the resonant circuit in the first state, the control device switches the switching element provided corresponding to the resonant circuit in the second state to a conductive state.

5. An aerosol generating device as described in claim 1, wherein the switching element is arranged in parallel with the capacitor relative to the coil between each resonant circuit and the ground, the switching element has a first switching element and a second switching element connected in series, the body diode formed in the first switching element and the body diode formed in the second switching element are opposite in direction to each other, and when driving the drive circuit arranged corresponding to the resonant circuit to be set to the first state, the control device switches the first switching element and the second switching element arranged corresponding to the resonant circuit in the second state to a conductive state.

6. An aerosol generating device as described in claim 1, wherein, when the switching element is in a conductive state, the resonant circuit and the switching element form a loop circuit through which an induced current generated in the resonant circuit flows in a loop via the ground, and when the control device drives the drive circuit provided corresponding to the resonant circuit in the first state, it switches the switching element provided corresponding to the resonant circuit in the second state to the conductive state.

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