Aerosol generation device

Abstract

This aerosol generation device includes: a heating unit that heats an aerosol source; a first temperature sensor that measures a temperature change in a measurement portion caused by the heating by the heating unit; a first AD conversion circuit that converts an output voltage of the first temperature sensor to digital data; a second temperature sensor that measures a temperature change in the heating unit; and a second AD conversion circuit that converts an output voltage of the second temperature sensor to digital data, wherein the first AD conversion circuit is higher in conversion precision than the second AD conversion circuit, and the second AD conversion circuit is faster in conversion speed than the first AD conversion circuit.

Description

Aerosol Generator

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

[0002] Aerosol generators, which are portable electronic devices, are equipped with various electronic components, such as a microcontroller unit (MCU), memory, an analog-to-digital (AD) conversion circuit, a sensor, a heater, and a light-emitting diode (LED). Incidentally, multiple AD conversion circuits are installed, one for each voltage value or signal value to be converted.

[0003] Chinese Utility Model No. 211882197 Chinese Patent No. 108802606 Chinese Utility Model No. 209563498

[0004] Aerosol generators use successive approximation AD converters, which are general-purpose AD converters. Successive approximation AD converters are known as AD converters that offer a good balance between conversion speed and conversion accuracy. In the case of an aerosol generator having a heating source that heats an aerosol source, the conversion speed is important for controlling the temperature of the heating unit itself, and the conversion accuracy is important for monitoring the temperature around the heating unit.

[0005] In view of the above problems, the present disclosure provides an aerosol generating device that has both high temperature control speed in a heating unit and high accuracy in detecting the temperature of a measurement site.

[0006] As one form of the present disclosure, an aerosol generating device is provided which has a heating unit that heats an aerosol source, a first temperature sensor that measures a temperature change at a measurement site due to heating of the heating unit, a first AD conversion circuit that converts the output voltage of the first temperature sensor into digital data, a second temperature sensor that measures the temperature change of the heating unit, and a second AD conversion circuit that converts the output voltage of the second temperature sensor into digital data, wherein the first AD conversion circuit has higher conversion accuracy than the second AD conversion circuit, and the second AD conversion circuit has a faster conversion speed than the first AD conversion circuit.

[0007] Here, a sigma-delta AD converter circuit may be used as the first AD converter circuit, and a successive approximation type or pipeline type AD converter circuit may be used as the second AD converter circuit.

[0008] Furthermore, the first temperature sensor may be operated using the reference voltage of the first AD conversion circuit as an operating power supply.

[0009] The first temperature sensor may have a non-linear temperature characteristic.

[0010] The first temperature sensor may measure the temperature of the housing or the surroundings of the heating unit, and the second temperature sensor may measure a change in temperature of the heating unit based on the control sequence.

[0011] The first temperature sensor may measure the temperature of the housing or the vicinity of the heating unit, and the second temperature sensor may measure the temperature of the aerosol source.

[0012] The digital video signal processing device may further include a first constant voltage circuit that generates a reference voltage for the first AD converter circuit and a second constant voltage circuit that generates an operating power supply for a memory that records an operation log, where the potential of the operating power supply for the memory and the potential of the reference voltage are the same.

[0013] The aerosol source may be a solid.

[0014] The aerosol source may be a liquid.

[0015] According to one aspect of the present disclosure, an aerosol generating device can be provided that has high temperature control speed in a heating unit and high accuracy in detecting the temperature of a measurement site.

[0016] FIG. 1 is a diagram of the front side of the aerosol generation device observed from diagonally above. FIG. 2 is a diagram of the front side of the aerosol generation device observed from diagonally below. FIG. 3 is a diagram of the main body device observed from the front with the front panel removed. FIG. 4 is a diagram schematically showing the internal configuration of the main body device. FIG. 5 is a diagram explaining an example of a heating profile used when the aerosol source is solid. FIG. 6 is a diagram schematically showing an electronic circuit used in embodiment 1. FIG. 7 is a diagram explaining the internal configuration of the MCU and the connection relationship with peripheral circuits. FIG. 8 is a diagram explaining an example of a heating profile used when the aerosol source is liquid.

[0017] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In each drawing, the same parts are denoted by the same reference numerals.

[0018] <Terminology> The aerosol generating device according to each embodiment is a form of electronic cigarette. In the following description, the substance generated by the aerosol generating device is referred to as aerosol. Aerosol refers to a mixture of tiny liquid or solid particles suspended in a gas and air or other gases. In each embodiment, an aerosol generating device that generates aerosol without combustion is described. Note that inhaling aerosol generated by an aerosol generating device is also called "puffing." In each embodiment, an aerosol generating device to which a solid aerosol source can be attached is described. Note that the container that stores the solid aerosol source is referred to as either a "capsule" or a "stick-type substrate" depending on the product form. Capsules and stick-type substrates are consumables. For this reason, guidelines for replacement are set for capsules and stick-type substrates.

[0019] <Embodiment 1> <External Appearance Example> First, an external appearance example of the aerosol generation device used in embodiment 1 will be described. Fig. 1 is a view of the front side of the aerosol generation device 1 observed from diagonally above. Fig. 2 is a view of the front side of the aerosol generation device 1 observed from diagonally below. Fig. 3 is a view of the main device 20 observed from the front with the front panel 10 removed.

[0020] The aerosol generation device 1 used in this embodiment has a size that allows the user to hold it in one hand. The aerosol generation device 1 has a main body device 20, a front panel 10 attached to the front of the main body device 20, and a shutter 30 that is arranged on the top surface of the main body device 20 and can be slid along the top surface. The front panel 10 is a member that can be attached to and detached from the main body device 20. The front panel 10 is attached and detached by the user.

[0021] 1 and 2, the front panel 10 attached to the main device 20 covers the front portion of the main device 20. In other words, even after the front panel 10 is attached, the main device 20 can be observed from the outside except for the front portion. For example, the side, back, top, and bottom surfaces of the main device 20 can be observed from the outside even after the front panel 10 is attached.

[0022] A window 10A is provided in the front panel 10. The window 10A is provided in a position facing the light-emitting element on the main device 20 side. In the case of the first embodiment, the light-emitting element is an LED (=Light Emitting Diode) 20A shown in FIG. 3 . In the case of the first embodiment, eight LEDs 20A are provided in the main device 20. The window 10A in the first embodiment is made of a light-transmitting material. However, the window 10A may be a slit that penetrates from the front surface to the back surface.

[0023] The lighting and blinking patterns of the LED 20A are assigned to indicate the operating status of the aerosol generating device. For example, lighting and blinking of the LED 20A are assigned to indicate a status related to the heating of the aerosol source. Status related to the heating of the aerosol source include, for example, the completion of preparation for heating the aerosol source, the start of heating, the completion or end of heating, the number of aerosol sources available for inhalation, the remaining time available for inhalation, and an abnormality in the main body temperature. In addition, lighting and blinking of the LED 20A are assigned to indicate a malfunction or failure of the main body device 20, the remaining battery level, charging or completion of charging, the pairing status, and the like. Malfunctions here include abnormalities related to the ambient temperature. The lighting and blinking of the light-emitting element are controlled by the control unit 206 (see FIG. 4 ), which will be described later.

[0024] The front panel 10 also serves to buffer the propagation of heat emitted from the main device 20. In this embodiment, aerosol generation is permitted only when the front panel 10 is attached to the main device 20. The front panel 10 used in this embodiment deforms when a user presses a position below the window 10A with their fingertip, and returns to its original shape when the user stops pressing. This deformation makes it possible to operate the power button 20B provided on the main device 20 while the front panel 10 is attached to the main device 20.

[0025] A Type C USB (Universal Serial Bus) connector 21 is provided on the bottom side of the main device 20. The shape and type of the USB connector 21 are merely examples. In the case of the first embodiment, the USB connector 21 is used to charge a power supply unit 201 (see FIG. 4 ) built into the main device 20.

[0026] A hole (not shown) for inserting a stick-shaped substrate 40 (see FIG. 4) containing an aerosol source is provided on the top surface of the main device 20. The hole is exposed by sliding the shutter 30 to the open position and is concealed by sliding the shutter 30 to the closed position. The stick-shaped substrate 40 used in this embodiment has a structure in which a solid aerosol source is stored in a substantially cylindrical paper tube.

[0027] A magnet, for example, is attached to the back surface of the shutter 30. Meanwhile, a Hall IC is attached to the main device 20 within the movable range of the shutter 30. The Hall IC is a magnetic sensor comprised of a Hall element and an operational amplifier, etc., and outputs a voltage according to the strength of the magnetic field that crosses the Hall element. In this embodiment, the opening and closing of the shutter 30 is detected from the change in voltage output from the Hall IC as the shutter 30 slides. In other words, it is detected whether the shutter 30 is in the open or closed position.

[0028] As shown in FIG. 3 , a power button 20B is located approximately in the center of the front of the main device 20. As described above, the power button 20B can be operated with the front panel 10 attached. The power button 20B is used, for example, to turn the power of the main device on and off, turn on and off the power supply to the heating unit 207 (see FIG. 4 ) that heats the aerosol source, and issue a Bluetooth (registered trademark) pairing command. Note that if the power button 20B is pressed and held (for example, for 5 seconds or more) with the front panel 10 detached from the main device 20, a reset function is activated. In this embodiment, BLE (Bluetooth Low Energy) is used as Bluetooth.

[0029] 3, magnets 20C used to attach the front panel 10 are disposed at the top and bottom of the front of the main unit 20. The magnets 20C are disposed in positions facing a magnet (not shown) disposed inside the front panel 10. For example, if the magnet on the front panel 10 has a north pole, the magnet 20C on the main unit 20 side has a south pole. The front panel 10 is detachably attached to the main unit 20 by the attractive force between the magnets.

[0030] Either the magnet on the front panel 10 side or the magnet 20C on the main device 20 side may be a piece of iron or other magnetic metal. Attachment of the front panel 10 to the main device 20 is detected by a Hall IC provided on the main device 20 side. The main device 20 also incorporates various electronic components necessary for generating aerosol. In the first embodiment, the device configuration in which the front panel 10 is attached to the main device 20 is referred to as the aerosol generation device 1, but in a narrower sense, the main device 20 is referred to as the aerosol generation device.

[0031] <Internal Configuration> Fig. 4 is a diagram showing a schematic diagram of the internal configuration of the main device 20. Fig. 4 also shows the state in which the stick-shaped substrate 40 is attached to the main device 20. The internal configuration shown in Fig. 4 is intended to explain the components provided in the main device 20 and their positional relationships. For this reason, the appearance of the components, etc. shown in Fig. 4 does not necessarily match the appearance diagram described above.

[0032] The main device 20 is composed of a power supply unit 201, a sensor unit 202, a notification unit 203, a memory unit 204, a communication unit 205, a control unit 206, a heating unit 207, a heat insulating unit 208, and a holding unit 209. As mentioned above, Fig. 4 shows a state in which the stick-shaped substrate 40 is held by the holding unit 209. In this state, the user inhales the aerosol.

[0033] The power supply unit 201 is a unit that supplies power to each component. The power supply unit 201 uses a secondary battery to store the power required by the main unit 20. In the first embodiment, a lithium-ion secondary battery, for example, is used as the secondary battery. The secondary battery can be charged from an external power source. In the first embodiment, the external power source is supplied via the USB connector 21 (see FIG. 2). Hereinafter, the power source supplied from the secondary battery will be referred to as "VBAT," and the power source supplied via the USB connector 21 will be referred to as "VBUS." The power source VBUS is a 5V power source. The 5V power source can also be generated from VBAT.

[0034] The sensor unit 202 is an electronic component that detects various types of information related to the main device 20. The sensor unit 202 includes, for example, a pressure sensor such as a microphone capacitor and a flow rate sensor. The sensor unit 202 outputs the detected information to the control unit 206. For example, when the sensor unit 202 detects a change in air pressure or air flow associated with inhalation, it outputs a numerical value indicating the inhalation of aerosol by the user to the control unit 206.

[0035] The sensor unit 202 is provided in correspondence with, for example, a button or switch used to receive an operation from a user. The button here is the power button 20B (see FIG. 3) described above. The switch is the shutter 30 (see FIG. 1) described above. When the sensor unit 202 detects a user operation, it outputs the detection of the operation to the control unit 206.

[0036] In addition, the sensor unit 202 has a temperature sensor that detects the temperature of the heating unit 207. The temperature sensor detects the temperature of the heating unit 207 based on, for example, changes in the electrical resistance value of the conductive track of the heating unit 207. The temperature sensor outputs a voltage corresponding to the current electrical resistance value. The control unit 206 calculates the temperature of the heating unit 207 from the output voltage of the temperature sensor. This temperature sensor is used for the purpose of changing the temperature of the heating unit 207 according to a heating profile.

[0037] FIG. 5 is a diagram illustrating an example of a heating profile used when the aerosol source is a solid. The horizontal axis represents the elapsed time from the start of heating. The vertical axis represents the target temperature. In the heating profile shown in FIG. 5, a preheating period is provided before the inhalation period. The preheating period corresponds to a preparation period for generating a sufficient amount of aerosol from the start of inhalation. This is because the temperature of the aerosol source before heating by the heating unit 207 begins is the same as room temperature, and a sufficient amount of aerosol cannot be generated immediately after operating the power button. The target temperature of the heating unit 207 during the preheating period is T1. In this embodiment, the target temperature T1 is set to the highest temperature during the entire period.

[0038] If the temperature of heating unit 207 continues to be maintained at target temperature T1 after the preheating period, not only will the amount of aerosol generated be excessive, but the amount of aerosol generated will also be unstable throughout the inhalation period. Therefore, after the aerosol source is sufficiently heated, the temperature of heating unit 207 is lowered to target temperature T3. Furthermore, during the latter half of the inhalation period, the temperature of heating unit 207 is raised to target temperature T2 (>T3) so that the amount of aerosol generated remains constant throughout the entire period. This heating profile is stored in storage unit 204 as a data file that defines the time change in the target temperature after heating begins.

[0039] In this embodiment, one heating profile is stored in the memory unit 204. However, it may be possible to store multiple heating profiles. If multiple heating profiles can be stored, the heating profile to be used for heating the aerosol source is selected in advance. The heating profile is also called a "control profile" or a "control sequence." Other temperature sensors include a temperature sensor that detects the ambient temperature of the heating unit 207 and a temperature sensor that detects the temperature near the surface of the main unit 20. These two temperature sensors are used to detect unexpected temperature increases. In other words, the temperature sensors here are provided from a safety perspective.

[0040] The notification unit 203 is an electronic component that notifies the user of various information related to the main device 20. The notification unit 203 includes, for example, an LED 20A (see FIG. 3). The light emission and blinking of the LED 20A are controlled in a pattern corresponding to the content of the notification. If multiple LEDs 20A with different light emission colors are provided, the light emission and blinking may be performed in a combination of different light emission colors. For example, red may be used to notify that the device is in a state where it needs to be stopped from use or repaired, and white, green, blue, etc. may be used to notify that the device is in a normal use state.

[0041] The notification unit 203 may include other devices used together with the LED 20A or instead of the LED 20A. The other devices include a display device that displays text, images, and other information, a sound output device that outputs sound, and a vibration device that vibrates the main body device 20. The light-emitting device, the display device, the sound output device, the vibration device, and the like are also used to notify the operating status of the aerosol generation device 1.

[0042] The storage unit 204 is an electronic component that stores various information related to the operation of the main device 20. The storage unit 204 is configured, for example, with a non-volatile semiconductor storage medium such as a flash memory. The information stored in the storage unit 204 includes, for example, an OS (Operating System), FW (Firmware), and other programs. The information stored in the storage unit 204 also includes, for example, information related to the control of the electronic components. The control information includes information related to suction by the user, such as the number of suctions, the suction time, and the cumulative suction time. This information is also called an operation log.

[0043] The communication unit 205 is a communication interface for enabling communication between the main device 20 and other devices. The communication unit 205 communicates with other devices in accordance with any wired or wireless communication standard. Examples of communication standards include wireless LAN (Local Area Network), USB, Wi-Fi (registered trademark), and Bluetooth (registered trademark). For example, the communication unit 205 transmits information about the user's inhalation to a smartphone. The communication unit 205 also downloads update programs and a heating profile that defines the temperature change of the heating unit 207 in heating mode from a server.

[0044] The control unit 206 functions as an arithmetic processing unit or control device, and controls the operation of each unit constituting the main unit 20 in accordance with various programs. Control signals are transmitted via a signal line different from the power line. For example, communication within the main unit 20 uses a serial communication method such as the I2C (Inter-Integrated Circuit) communication method, the SPI (Serial Peripheral Interface) communication method, or the UART (Universal Asynchronous Receiver Transmitter) communication method.

[0045] The control unit 206 is realized by electronic circuits such as a CPU (Central Processing Unit), MCU (Micro Controller Unit), MPU (Micro Processing Unit), GPU (Graphical Processing Unit), ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array), DSP (Digital Signal Processor), etc. The control unit 206 may include a ROM (Read Only Memory) that stores programs, calculation parameters, etc., and a RAM (Random Access Memory) that temporarily stores parameters that change as appropriate.

[0046] The control unit 206 executes various processes and controls through the execution of programs. The processes and controls here include, for example, power supply by the power supply unit 201, charging of the power supply unit 201, detection of information by the sensor unit 202, notification of information using the notification unit 203, writing of information to the storage unit 204 or reading of information from the storage unit 204, and transmission and reception of information using the communication unit 205. In addition, the control unit 206 also controls input of information to electronic components, processing based on information output from electronic components, and the like.

[0047] The holding part 209 is a roughly cylindrical container. In this embodiment, the space inside the holding part 209, defined by the inner wall and the bottom surface, is referred to as the internal space 209A. The internal space 209A is roughly columnar. The holding part 209 here corresponds to the hole exposed by sliding the shutter 30. The holding part 209 is provided with an opening 209B that connects the internal space 209A to the outside. The stick-shaped substrate 40 is inserted into the internal space 209A through this opening 209B. The stick-shaped substrate 40 is inserted until its tip hits the bottom 209C. Only a portion of the stick-shaped substrate 40 is accommodated in the internal space 209A. A state in which the stick-shaped substrate 40 is accommodated in the internal space 209A is referred to as the stick-shaped substrate 40 being held in the internal space 209A.

[0048] The holding part 209 is formed so that the inner diameter of at least a portion of its axial direction is smaller than the outer diameter of the stick-shaped substrate 40. For this reason, the outer peripheral surface of the stick-shaped substrate 40 inserted into the internal space 209A is compressed by the inner wall of the holding part 209. This compression causes the stick-shaped substrate 40 to deform and be held in the internal space 209A. The holding part 209 also has the function of defining the flow path of air passing through the stick-shaped substrate 40. An air inlet, which is the entrance of air to the flow path, is located, for example, in the bottom part 209C. Note that the opening 209B corresponds to an air outlet, which is the air outlet.

[0049] In the present embodiment, only a portion of the stick-type substrate 40 is held in the holding portion 209, with the remainder protruding from the housing. Hereinafter, the portion of the stick-type substrate 40 held in the holding portion 209 will be referred to as the substrate portion 40A, and the portion protruding from the housing will be referred to as the mouthpiece portion 40B. At least the substrate portion 40A contains an aerosol source. The aerosol source is a substance that is atomized by heating to generate an aerosol. Aerosol sources include shredded tobacco, as well as processed products in which tobacco raw materials are formed into granules, sheets, or powder, and other tobacco-derived substances.

[0050] Furthermore, the aerosol source may include non-tobacco-derived substances made from plants other than tobacco, such as mint or herbs. For example, the aerosol source may include a flavoring component such as menthol. If the main device 20 is a medical inhaler, the aerosol source may include a medication for inhalation by the patient. Note that the aerosol source is not limited to solids and may be, for example, a polyhydric alcohol such as glycerin or propylene glycol, or a liquid such as water.

[0051] At least a portion of the suction mouth portion 40B is held in the user's mouth when inhaling. When the user holds the suction mouth portion 40B in their mouth and inhales, air flows into the internal space 209A through the air inlet hole. The inflowing air passes through the internal space 209A and the base portion 40A and reaches the user's mouth. The air that reaches the user's mouth contains aerosol generated in the base portion 40A.

[0052] The heating unit 207 is composed of a heater or other heating element. The heating unit 207 is composed of any material, such as metal or polyimide. The heating unit 207 is, for example, in the form of a film, and is attached to the outer circumferential surface of the holding unit 209. The aerosol source contained in the stick-shaped substrate 40 is heated and atomized by the heat generated by the heating unit 207. The atomized aerosol source is mixed with air or the like to generate an aerosol. In the case of FIG. 4 , the area near the periphery of the stick-shaped substrate 40 is heated first, and the heated range gradually moves toward the center.

[0053] For this reason, atomization of the aerosol source begins near the periphery of the stick-shaped substrate 40 and gradually moves toward the center. The heating unit 207 generates heat when power is supplied from the power supply unit 201. For example, when a predetermined user operation is detected by the sensor unit 202, power supply to the heating unit 207 is permitted. The predetermined user operation here includes operation of the shutter 30 (see FIG. 1) or the power button 20B (see FIG. 3).

[0054] When the temperature of the stick-shaped substrate 40 heated by the heating unit 207 reaches a predetermined temperature, the user can inhale the substrate. The change in the target temperature over time from the start of heating to the end of heating is stored in the storage unit 204 as a heating profile. The heating profile is an example of a control sequence. The inhalation of the aerosol by the user is detected by a flow rate sensor or the like of the sensor unit 202 and stored in the storage unit 204. When a predetermined time has passed since the start of heating, or when a predetermined operation by the user is detected, power supply to the heating unit 207 is stopped. The predetermined operation is, for example, removing the stick-shaped substrate 40.

[0055] In the example of FIG. 4 , the heating unit 207 is disposed on the outer periphery of the stick-shaped substrate 40, but the heating unit 207 may be a blade-shaped metal piece inserted into the stick-shaped substrate 40. Alternatively, an induction heating method, for example, may be used to atomize the aerosol source. In this type of heating method, the heating unit 207 has at least an electromagnetic induction source, such as a coil that generates a magnetic field. In this case, a susceptor is disposed at a position overlapping with the magnetic field generated by the electromagnetic induction source. The susceptor generates heat in response to the generation of the magnetic field and heats the aerosol source. The susceptor may be a metal piece embedded in the stick-shaped substrate 40. When a metal piece acting as the heating unit 207 is embedded in the stick-shaped substrate 40, a coil that induction heats the metal piece is disposed around the holder 209. Alternatively, a susceptor may be disposed on the outer periphery of the stick-shaped substrate 40 within the main device 20, and a coil serving as an electromagnetic induction source may be wound around the outer periphery.

[0056] The heat insulating section 208 is a member that reduces the propagation of heat generated in the heating section 207 to the surrounding area. For this reason, the heat insulating section 208 is arranged so as to cover at least the outer peripheral surface of the heating section 207. The heat insulating section 208 is made of, for example, a vacuum insulation material, an aerogel insulation material, or the like. A vacuum insulation material is an insulation material in which, for example, glass wool and silica (silicon powder) are wrapped in a resin film and placed in a high vacuum state, thereby reducing the thermal conduction of gases to as close to zero as possible.

[0057] <General Configuration of Electronic Circuit> Fig. 6 is a diagram showing a schematic diagram of an electronic circuit used in embodiment 1. Fig. 6 shows the connection relationships between representative components. In Fig. 6, wiring used to supply power (hereinafter referred to as "power lines") is shown with thick lines, and wiring used for control, etc. (hereinafter referred to as "signal lines") is shown with thin lines.

[0058] The electronic circuit shown in FIG. 6 is composed of a charging IC 211, a step-up / step-down DC / DC circuit 212, an MCU 213, a step-up DC / DC circuit 214, a heater switch 215A, a resistance value measurement switch 215B, a heater unit 216, an operational amplifier 217, a fuel gauge IC 218, an LDO (=Low Dropout) constant voltage circuit 219, a flash memory 220, a heater temperature sensor 221, a case temperature sensor 222, and an LED 20A.

[0059] The charging IC 211 is an electronic circuit that switches the power supply path. For example, when a USB cable is connected to the USB connector 21 (see FIG. 2 ), the charging IC 211 connects the power supply VBUS to the step-up / step-down DC / DC circuit 212 and the power supply VBAT. On the other hand, when a USB cable is not connected to the USB connector 21, the charging IC 211 connects the power supply VBAT to the step-up / step-down DC / DC circuit 212.

[0060] The charging IC 211 detects whether a USB cable is connected to the USB connector 21 and switches the power supply path depending on the detection result. When the charging IC 211 lights up the LED 20A with the USB cable not connected, the charging IC 211 generates a 5V power supply by OTG (= On-The-Go) and applies it to the power supply line for the LED 20A.

[0061] The step-up / step-down DC / DC circuit 212 is a circuit that converts the power supply VBUS or power supply VBAT supplied from the charging IC 211 into a constant voltage system power supply Vsys. In the present embodiment, the system power supply Vsys is 3.3 V. In the case of FIG. 6 , the system power supply Vsys is supplied to the MCU 213, the fuel gauge IC 218, and the LDO constant voltage circuit 219.

[0062] For example, when a power supply VBAT is supplied, the step-up / step-down DC / DC circuit 212 generates the system power supply Vsys by stepping up or down the power supply VBAT. The power supply VBAT fluctuates depending on the remaining capacity and degree of deterioration of the secondary battery, but is converted to a constant voltage by the step-up / step-down DC / DC circuit 212. On the other hand, when a voltage derived from the power supply VBUS (i.e., a 5V power supply) is supplied, the step-up / step-down DC / DC circuit 212 steps down the supplied voltage to generate the system power supply Vsys.

[0063] The MCU 213 is an example of the control unit 206 (see FIG. 4 ) that controls the operation of each component of the aerosol generation device 1 (see FIG. 1 ), and is powered by the system power supply Vsys. The MCU 213 is composed of multiple electronic components. For example, the MCU 213 is composed of an AD conversion circuit that converts analog signals input from an input terminal into digital data, an LDO constant voltage circuit that generates various power sources, and a field effect transistor (FET) that controls the operation of an external element (e.g., LED 20A).

[0064] The MCU 213 has a function of detecting the temperature using the case temperature sensor 222 before starting heating of the stick-shaped substrate 40 (see FIG. 4) by the heater unit 216, and if the detected temperature exceeds a threshold value, not starting heating of the stick-shaped substrate 40 by the heater unit 216. The threshold value here may be, for example, the upper and lower limit temperatures of the usage environment temperature, or the upper limit of the temperature allowable at the measurement site.

[0065] The step-up DC / DC circuit 214 converts the power supply VBAT supplied from the secondary battery into a constant voltage boost power supply Vboost. The boost power supply Vboost has a higher potential than the system power supply, for example, 5 V. In the case of FIG. 6 , for the purpose of load distribution, the 5 V power supply supplied to the LED 20A and the boost power supply Vboost supplied to the heater unit 216 are wired separately.

[0066] The heater switch 215A is a switch that controls the application of boost power Vboost to the heater unit 216, and is configured, for example, with an FET. In this embodiment, the opening and closing of the heater switch 215A is controlled by the MCU 213 using PWM (=Pulse Width Modulation). By PWM control of the heater switch 215A, the temperature of the heater unit 216 is controlled to match a heating profile. The heating profile is data that provides a target temperature according to elapsed time, and is stored in the storage unit 204 (see FIG. 4). The opening and closing control of the heater switch 215A may be initiated by detecting a predetermined user input, for example, an input from the power button 20B (see FIG. 3).

[0067] The resistance measurement switch 215B is a switch that is controlled to be open when the resistance of the heater unit 216 is being detected and is controlled to be closed when the resistance is not being detected, and is configured, for example, by an FET. The opening and closing of the resistance measurement switch 215B is also controlled by the MCU 213. The resistance measurement switch 215B is controlled to be closed when the heater switch 215A is in the open state. When the resistance measurement switch 215B is controlled to be closed, the boost power supply Vboost is applied to the operational amplifier 217. In addition, a resistor R is connected in series to the heater unit 216. As a result, a voltage Vheat, which is obtained by dividing the boost power supply Vboost in accordance with the ratio of the resistance of the resistor R to the resistance of the heater unit 216 (i.e., the resistance ratio), appears at the connection midpoint between the resistor R and the heater unit 216.

[0068] The heater unit 216 is an example of the heating section 207 that generates heat when energized and heats the stick-shaped substrate 40 inserted in the holding section 209. The resistance value of the heater unit 216 changes depending on the temperature of the heater unit 216. For example, the resistance value of the heater unit 216 increases as the temperature increases. As a result, the higher the temperature of the heater unit 216, the higher the potential of the voltage Vheat.

[0069] The operational amplifier 217 is a circuit that detects the resistance value of the heater unit 216. In this embodiment, the operational amplifier 217 uses the boost power supply Vboost as its operating power supply. As described above, the supply of the boost power supply Vboost to the operational amplifier 217 is limited to the timing of detecting the voltage Vheat, which corresponds to the resistance value of the heater unit 216. The operational amplifier 217 outputs a voltage corresponding to the voltage Vheat input to the non-inverting input terminal to the MCU 213. Through this voltage, the MCU 213 measures the temperature change of the heater unit 216. In this embodiment, the operational amplifier 217 that detects the voltage Vheat is an example of a second temperature sensor.

[0070] The fuel gauge IC 218 is an electronic component that operates using the system power supply Vsys as its operating power supply and calculates and stores the secondary battery's SOH (State of Health), SOC (State of Charge), full charge capacity, and remaining capacity by monitoring the power supply VBAT. The fuel gauge IC 218 notifies the MCU 213 of the calculated SOH and other information via I2C communication.

[0071] The LDO constant voltage circuit 219 is a power supply circuit that generates a predetermined voltage from the system power supply Vsys. In the case of FIG. 6, the LDO constant voltage circuit 219 outputs 1.8 V. The flash memory 220 is a non-volatile semiconductor memory that stores firmware and operation logs, and is an example of the storage unit 204. In the case of FIG. 6, the potential of the operating power supply for the flash memory 220 is 1.8 V. Note that SPI communication is used for communication between the flash memory 220 and the MCU 213.

[0072] The heater temperature sensor 221 is a temperature sensor that measures the temperature around the heater unit 216. The heater temperature sensor 221 is provided for the purpose of detecting abnormal heat generation. In other words, it is provided from the perspective of safety. In the present embodiment, a thermistor is used as the heater temperature sensor 221. A thermistor is a temperature sensor whose resistance value changes greatly with temperature changes. A thermistor is a temperature sensor that has non-linear temperature characteristics. The heater temperature sensor 221 is an example of a first temperature sensor.

[0073] The power supply voltage of the heater temperature sensor 221 shown in Figure 6 is 1.8 V. In this embodiment, the potential of the power supply voltage supplied to the heater temperature sensor 221 is the same as the potential of the power supply voltage supplied to the flash memory 220. Note that the potential of the power supply voltage supplied to the flash memory 220 and the potential of the power supply voltage supplied to the heater temperature sensor 221 do not need to be 1.8 V, and they do not need to be the same. An output voltage representing the temperature of the measurement site is provided from the heater temperature sensor 221 to the MCU 213.

[0074] The case temperature sensor 222 is a temperature sensor that measures the temperature near the surface of the main unit 20. The case temperature sensor 222 is also provided for the purpose of detecting abnormal heat generation. In other words, it is provided from the perspective of safety. In this embodiment, a thermistor is used as the case temperature sensor 222. The case temperature sensor 222 is also an example of a first temperature sensor.

[0075] The power supply voltage of the case temperature sensor 222 shown in Figure 6 is 1.8 V. In this embodiment, the potential of the power supply voltage supplied to the case temperature sensor 222 is the same as the potential of the power supply voltage supplied to the flash memory 220. Note that the potential of the power supply voltage supplied to the flash memory 220 and the potential of the power supply voltage supplied to the case temperature sensor 222 do not need to be 1.8 V, and they do not need to be the same. An output voltage indicating the temperature of the measurement site is provided to the MCU 213 from the case temperature sensor 222.

[0076] <Internal Structure of MCU> Fig. 7 is a diagram illustrating the internal structure of the MCU 213 and the connection relationship with peripheral circuits. Note that the internal structure of the MCU 213 shown in Fig. 7 is drawn from the perspective of electronic components connected to the power supply line. Needless to say, the MCU 213 includes various electronic components not shown in Fig. 7.

[0077] For example, a CPU is built in. The CPU here generates control signals for, for example, a heater switch 215A (see FIG. 6) and a resistance value measurement switch 215B (see FIG. 6). In addition, the MCU 213 is also provided with a switch (for example, an FET) that controls the turning on and off of the LED 20A (see FIG. 6).

[0078] 7 is provided with an LDO constant voltage circuit 231, sigma-delta (SD) ADCs 232 and 233, LDO constant voltage circuits 234 and 236, and general-purpose (GP) ADCs 235 and 237. However, the LDO constant voltage circuit 234 and the LDO constant voltage circuit 236 may be shared. Of these, the LDO constant voltage circuits 231, 234, and 236 are circuits that generate constant voltages, and the sigma-delta (SD) ADCs 232 and 233 and the general-purpose (GP) ADCs 235 and 237 are circuits that generate data required for the processing of the CPU described above.

[0079] As described above, the heater temperature sensor 221 and the case temperature sensor 222 are temperature sensors used from a safety perspective. Therefore, high conversion accuracy is required for the AD conversion circuit that converts the output voltage from this type of temperature sensor into digital data. In this embodiment, SD-type ADCs 232 and 233, which have high conversion accuracy, are used to convert the output voltages Vin1 and Vin2 of the heater temperature sensor 221 and the case temperature sensor 222. The SD-type ADCs 232 and 233 here are examples of first AD conversion circuits that convert the output voltage of the first temperature sensor into digital data.

[0080] On the other hand, the temperature of the heater unit 216 is measured for heating control based on a heating profile. Therefore, real-time conversion is required for the output voltage representing the resistance value that changes according to the temperature of the heater unit 216. In this embodiment, a GP-type ADC 235 with a high conversion speed is used to convert the output voltage of the operational amplifier 217.

[0081] The GP type ADC 235 is, for example, a successive approximation type ADC or a pipeline type ADC. The GP type ADC 235 here is an example of a second AD conversion circuit that converts the output voltage of the second temperature sensor into digital data. A GP type ADC 237, which has a larger input voltage fluctuation range than the SD type ADC 232, etc., is used to convert the potential that appears at the cc terminal of the USB cable.

[0082] The LDO constant voltage circuit 231 is a power supply circuit that generates 1.8V power from the system power supply Vsys. In this embodiment, the 1.8V power generated by the LDO constant voltage circuit 231 is supplied only to the flash memory 220. In other words, the LDO constant voltage circuit 231 is a power supply circuit dedicated to the flash memory 220. Note that although the LDO constant voltage circuit 231 is built into the MCU 213 in FIG. 7 , it is also possible to provide it outside the MCU 213.

[0083] 7, bidirectional arrows indicate signal lines used by the MCU 213 to write digital data to the flash memory 220 and read digital data from the flash memory 220. The LDO constant voltage circuit 231 here is an example of a second constant voltage circuit.

[0084] The LDO constant voltage circuit 219 is also a power supply circuit that generates 1.8V power from the system power supply Vsys. The LDO constant voltage circuit 219 is an example of a first constant voltage circuit. The 1.8V power generated by the LDO constant voltage circuit 219 is supplied to the heater temperature sensor 221, the case temperature sensor 222, and the SD-type ADCs 232 and 233 via a power line different from that of the LDO constant voltage circuit 231.

[0085] 7, the power supply line used to supply 1.8V power corresponding to the LDO constant voltage circuit 231 is different from the power supply line used to supply 1.8V power corresponding to the LDO constant voltage circuit 219. Therefore, even if the potential of the 1.8V power supply that supplies drive power to the flash memory 220 fluctuates as the flash memory 220 operates, the fluctuations will not be propagated to the potential of the 1.8V power supply supplied by the LDO constant voltage circuit 219. Thus, even if the flash memory 220 operates, the conversion accuracy of the SD ADC 232 and the SD ADC 233 will not decrease.

[0086] 7, the 1.8V power supply generated by the LDO constant voltage circuit 219 is supplied via a common power supply line to the heater temperature sensor 221 and the SD ADC 232. That is, the 1.8V power supply is supplied to the heater temperature sensor 221 as an operating power supply, and to the SD ADC 232 as a reference voltage Vref1.

[0087] Therefore, even if the potential of the power supply line connecting the heater temperature sensor 221 and the SD ADC 232 fluctuates due to superimposed noise, the fluctuations in the 1.8V power supply supplied to the heater temperature sensor 221 and the fluctuations in the 1.8V power supply (reference voltage Vref1) supplied to the SD ADC 232 change in phase. As a result, the effects of the fluctuations in the power supply potential are canceled out. Therefore, the conversion accuracy of the SD ADC 232 does not decrease. The converted output of the SD ADC 232 is output to a CPU (not shown).

[0088] Similarly, the 1.8V power supply generated by the LDO constant voltage circuit 219 is supplied via a common power supply line to the case temperature sensor 222 and the SD ADC 233. That is, the 1.8V power supply is supplied to the case temperature sensor 222 as an operating power supply, and to the SD ADC 233 as a reference voltage Vref1.

[0089] Therefore, even if the potential of the power supply line connecting the case temperature sensor 222 and the SD ADC 233 fluctuates due to superimposed noise, the fluctuations in the 1.8V power supply supplied to the case temperature sensor 222 and the fluctuations in the 1.8V power supply (reference voltage Vref1) supplied to the SD ADC 233 change in phase. As a result, the effects of the fluctuations in the power supply potential are canceled out. Therefore, the conversion accuracy of the SD ADC 233 does not decrease. The conversion output of the SD ADC 233 is also output to a CPU (not shown).

[0090] 7, the LDO constant voltage circuit 219 is provided outside the MCU 213, but it may be provided inside the MCU 213. In addition, the MCU 213 is provided with an LDO constant voltage circuit 234 that generates a constant voltage operating power supply Vref2 from the system power supply Vsys, and an LDO constant voltage circuit 236 that generates a constant voltage operating power supply Vref3 from the system power supply Vsys.

[0091] Here, the operating power supplies Vref2 and Vref3 may be, for example, 1.8 V. In Fig. 7, the operating power supplies Vref2 and Vref3 are written assuming a case where the power supply is not 1.8 V. Note that the operating power supplies Vref2 and Vref3 may be at the same potential or at different potentials.

[0092] <Effects> In the aerosol generation device 1 according to this embodiment (see FIG. 1 ), the SD-type ADCs 232 and 233 that convert the output voltage of the temperature sensor, which is provided for safety reasons, into digital data use ADCs with higher conversion accuracy than the GP-type ADC 235 that converts the output voltage of the heater unit 216 into digital data. On the other hand, the GP-type ADC 235 that converts the output voltage of the heater unit 216 into digital data uses an ADC with a faster conversion speed than the SD-type ADCs 232 and 233 that convert the output voltage of the temperature sensor, which is provided for safety reasons, into digital data. This makes it possible to provide an aerosol generation device that has high temperature control speed in the heating unit 207 and high temperature detection accuracy at the measurement site.

[0093] Furthermore, in the aerosol generation device 1 according to this embodiment, the reference voltage Vref1 of the SD-type ADC 232 is also supplied as an operating power supply to the heater temperature sensor 221. The reference voltage Vref1 of the SD-type ADC 233 is also supplied as an operating power supply to the case temperature sensor 222. Therefore, even if the potential of the operating power supply (or the reference voltage Vref1) fluctuates, it is possible to offset the influence of the potential fluctuation, thereby improving the conversion accuracy of the ADC. In other words, the temperature measurement accuracy can be improved.

[0094] <Other Embodiments> (1) Although the embodiments of the present disclosure have been described above, the technical scope of the present disclosure is not limited to the scope described in the above-described embodiments. It is clear from the claims that various modifications or improvements to the above-described embodiments are also included in the technical scope of the present disclosure.

[0095] (2) In the above embodiment, the case where the temperature change of the heater unit 216 is measured has been described. However, the temperature change of the stick-shaped substrate 40 may also be measured. In other words, the temperature change of the aerosol source may also be measured. The temperature change of the aerosol source may be measured, for example, via a temperature sensor provided on the bottom 209C of the holder 209 (see FIG. 4). Alternatively, the temperature change of the aerosol source may be measured indirectly via the voltage Vheat appearing in the heater unit 216.

[0096] (3) In the above embodiment, the SD ADCs 232 and 233 are given as an example of an electronic circuit that provides a constant voltage circuit separate from the constant voltage circuit that supplies operating power to the flash memory 220 even when the electronic circuit operates at the same potential as the flash memory 220. However, this type of electronic circuit is not limited to the SD ADCs 232 and 233. For example, this type of electronic circuit may include an AD conversion circuit (not shown) that is used to measure the temperature around the secondary battery.

[0097] (4) In the above-described embodiment, SD-type ADCs 232 and 233, which have high conversion accuracy, are used as AD conversion circuits that provide a constant voltage circuit separate from the constant voltage circuit that supplies operating power to the flash memory 220, even when the ADCs operate at the same potential as the flash memory 220. However, GP-type ADCs 235 and 237, which have high conversion speeds, may also be used.

[0098] (5) In the above embodiment, the aerosol source is described as being solid. However, the aerosol source may be liquid. When the aerosol source is liquid, a method is adopted in which the aerosol source is guided to a thin tube called a wick by capillary action, and the aerosol source is evaporated by heating a coil wrapped around the wick. When the aerosol source is liquid, the aerosol source is heated in conjunction with the user's inhalation.

[0099] That is, when the sensor unit 202 (see FIG. 4) detects the user's inhalation, the liquid aerosol source is heated. However, an upper limit (e.g., 2.5 seconds) is set for the heating time per inhalation, and heating of the aerosol source is stopped when the upper limit is reached, even if the inhalation continues beyond the upper limit. Note that the amount of power required for heating a liquid aerosol source is less than that required for a solid aerosol source.

[0100] 8 is a diagram illustrating an example of a heating profile used when the aerosol source is a liquid. In FIG. 8, the horizontal axis represents the number of inhalations. The left vertical axis represents the amount of flavor component, and the right vertical axis represents the target temperature. Note that the multiple circles in the diagram represent the measurement results of the amount of flavor component according to the number of inhalations, and the line graph represents the target temperature of the heating unit 207 for converging the amount of flavor component to the target amount.

[0101] (6) In the above embodiment, the aerosol generator generates an aerosol by heating a solid aerosol source. However, the aerosol generator may generate an aerosol by separately heating a solid aerosol source and a liquid aerosol source. This type of aerosol generator is also called a hybrid aerosol generator.

[0102] <Summary> The present disclosure includes the following configurations: (1) An aerosol generation device including a heating unit that heats an aerosol source, a first temperature sensor that measures a temperature change at a measurement site due to heating of the heating unit, a first AD conversion circuit that converts an output voltage of the first temperature sensor into digital data, a second temperature sensor that measures a temperature change at the heating unit, and a second AD conversion circuit that converts the output voltage of the second temperature sensor into digital data, wherein the first AD conversion circuit has higher conversion accuracy than the second AD conversion circuit, and the second AD conversion circuit has a faster conversion speed than the first AD conversion circuit. (2) The aerosol generation device described in (1), wherein the first AD conversion circuit is a sigma-delta AD conversion circuit, and the second AD conversion circuit is a successive approximation type or a pipeline type AD conversion circuit. (3) The aerosol generation device described in (1) or (2), wherein the first temperature sensor operates using a reference voltage of the first AD conversion circuit as an operating power source. (4) The aerosol generating device according to any one of (1) to (3), wherein the first temperature sensor has a nonlinear temperature characteristic. (5) The aerosol generating device according to any one of (1) to (4), wherein the first temperature sensor measures the temperature of the housing or the area around the heating unit, and the second temperature sensor measures a temperature change in the heating unit based on a control sequence. (6) The aerosol generating device according to any one of (1) to (4), wherein the first temperature sensor measures the temperature of the housing or the area around the heating unit, and the second temperature sensor measures the temperature of the aerosol source. (7) The aerosol generating device according to any one of (1) to (6), wherein the aerosol generating device has a first constant voltage circuit that generates a reference voltage for the first AD conversion circuit and a second constant voltage circuit that generates an operating power supply for a memory that records an operation log, and wherein the potential of the operating power supply for the memory is the same as the potential of the reference voltage. (8) The aerosol generating device according to any one of (1) to (6), wherein the aerosol source is solid. (9) An aerosol generating device according to any one of (1) to (6), wherein the aerosol source is a liquid.

[0103] DESCRIPTION OF SYMBOLS 1...Aerosol generating device, 10...Front panel, 10A...Window, 20...Main body device, 20A...LED, 20B...Power button, 20C...Magnet, 21...USB connector, 30...Shutter, 40...Stick-shaped substrate, 40A...Substrate part, 40B...Suction mouth part, 201...Power supply part, 202...Sensor part, 203...Notification part, 204...Memory part, 205...Communication part, 206...Control part, 207...Heating part, 208...Insulation part, 209...Holding part, 209A...Internal space, 209 B...opening, 209C...bottom, 212...step-up / step-down DC / DC circuit, 213...MCU, 214...step-up DC / DC circuit, 215A...heater switch, 215B...resistance value measurement switch, 216...heater unit, 217...op-amp, 219, 231, 234, 236...LDO constant voltage circuit, 220...flash memory, 221...heater temperature sensor, 222...case temperature sensor, 232, 233...SD type ADC, 235, 237...GP type ADC

Claims

1. a heating unit that heats the aerosol source; a first temperature sensor for measuring a temperature change at a measurement site caused by heating of the heating unit; a first AD conversion circuit that converts the output voltage of the first temperature sensor into digital data; a second temperature sensor for measuring a temperature change of the heating unit; a second AD conversion circuit that converts the output voltage of the second temperature sensor into digital data; and the first AD conversion circuit has higher conversion accuracy than the second AD conversion circuit; the second AD conversion circuit has a conversion speed faster than that of the first AD conversion circuit; Aerosol generator.

2. the first AD converter circuit is a sigma-delta AD converter circuit, the second AD conversion circuit is a successive approximation type or a pipeline type AD conversion circuit; The aerosol generating device according to claim 1 .

3. the first temperature sensor operates using a reference voltage of the first AD conversion circuit as an operating power supply; The aerosol generating device according to claim 1 or 2.

4. the first temperature sensor has a nonlinear temperature characteristic; The aerosol generating device according to claim 1 .

5. the first temperature sensor measures a temperature around the housing or the heating unit; the second temperature sensor measures a temperature change of the heating unit based on a control sequence; The aerosol generating device according to claim 1 .

6. the first temperature sensor measures a temperature around the housing or the heating unit; the second temperature sensor measures the temperature of the aerosol source; The aerosol generating device according to claim 1 .

7. a first constant voltage circuit that generates a reference voltage for the first AD conversion circuit; a second constant voltage circuit that generates an operating power supply for a memory that records an operation log; and the potential of the operating power supply of the memory is the same as the potential of the reference voltage; The aerosol generating device according to claim 1 .

8. the aerosol source is a solid; The aerosol generating device according to claim 1 .

9. the aerosol source is a liquid; The aerosol generating device according to claim 1 .