Circuitry for an aerosol generation device and aerosol generation device

Abstract

The utility model discloses a kind of circuit capable for aerosol generating device, aerosol generating device is equipped with containing cavity, containing cavity is used to accommodate electromagnetic induction type aerosol generating product, aerosol generating device includes first coil, circuit includes: detection circuit, comprising: first resonant amplification circuit, for determining the electromagnetic signal of first coil, first resonant amplification circuit includes first inductor, first resistance and first capacitor, wherein, first inductor and first resistance come from the first coil of access, electromagnetic signal is used to determine whether the object to be measured of being put into containing cavity is foreign matter, to make aerosol generating device be in heating state or non-heating state.The utility model further discloses a kind of aerosol generating device.Above-mentioned technical means, can determine the electromagnetic signal of first coil, the electromagnetic signal can be used to determine foreign matter detection result, provide guarantee for the reliability and user safety of electromagnetic induction type aerosol generating device.

Description

Technical Field

[0001] This utility model relates to the field of novel tobacco products, and in particular to a circuit for an aerosol generating device and an aerosol generating device. Background Technology

[0002] Electromagnetic induction heated tobacco products are a new type of tobacco product based on the principle of electromagnetic induction. Unlike traditional combustion methods, they use electromagnetic induction to precisely control the temperature and heat the tobacco evenly, allowing it to release the desired flavor and nicotine at a lower temperature. This effectively avoids the generation of harmful substances caused by high-temperature combustion, thereby reducing potential health risks to users and minimizing secondhand smoke pollution, making them healthier and more environmentally friendly.

[0003] However, existing technologies suffer from a core flaw: the electromagnetic properties of metallic objects within foreign objects can be confused with those of standard heating components. When a user mistakenly inserts an everyday metal tool (such as tweezers or an ear pick) into the heating chamber, the existing aerosol generating device (heated cigarette device) may misinterpret it as a compatible cigarette and activate the heating mechanism. If the user uses the device without noticing the abnormality, it can cause contact burns (such as ear canal burns) or ignite nearby flammable materials (such as tissues), resulting in burn accidents. Simultaneously, when a metallic object enters the heating chamber of the induction coil, it can cause the heating system of the aerosol generating device to malfunction. This can lead to incorrect energy transfer to the metallic object, causing localized overheating, short circuits, component burnout, and even a fire risk, seriously threatening user safety.

[0004] However, there is currently no suitable detection method to detect foreign objects containing metals, so as to upgrade aerosol generating devices from "circuit safety" to "electromagnetic safety" and provide assurance for the reliability and user safety of electromagnetic induction aerosol generating devices.

[0005] In addition to the problems mentioned above, existing aerosol generating devices also suffer from technical issues such as the use of multiple components, resulting in a non-compact and complex structure. Utility Model Content

[0006] In a first aspect, this application also provides a circuit for use in an aerosol generating device, the aerosol generating device having a receiving cavity for accommodating an electromagnetic induction type aerosol generating article, the aerosol generating device including a first coil, and the circuit including:

[0007] The detection circuit includes:

[0008] The first resonant amplifier circuit is used to determine the electromagnetic signal of the first coil. The first resonant amplifier circuit includes a first inductor, a first resistor, and a first capacitor. The first inductor and the first resistor are derived from the first coil. The electromagnetic signal is used to determine whether the object to be tested placed in the receiving cavity is a foreign object, so that the aerosol generating device is in a heated or unheated state.

[0009] According to the circuit for the aerosol generating device of this application, the electromagnetic signal of the first coil can be determined. This electromagnetic signal can be used to determine whether the test object is a foreign object, thus avoiding the abnormal start-up of the heating system of the aerosol generating device due to the insertion of a foreign object containing a metal body under abnormal use. This also avoids the risk of local overheating, short circuit, or component burnout caused by incorrect energy transfer to the foreign metal body. This upgrades the aerosol generating device from "circuit safety" to "electromagnetic safety", providing a guarantee for the reliability and user safety of electromagnetic induction aerosol generating devices.

[0010] In some embodiments, the circuit includes a first switch and a heating circuit, and the aerosol generating device further includes a second coil, one end of the first switch is connected to the second coil, and the other end of the first switch is connected to a detection circuit or a heating circuit.

[0011] In some embodiments, the detection circuit includes a second resonant amplifier circuit, the other end of the first switch is connected to the second resonant amplifier circuit, and is used to determine the electromagnetic signal of the second coil. The second resonant amplifier circuit includes a second inductor, a second resistor and a second capacitor, wherein the second inductor and the second resistor are derived from the connected second coil.

[0012] Secondly, this application also provides an aerosol generating apparatus, comprising:

[0013] A containment cavity for containing products generated by electromagnetic induction aerosols;

[0014] First coil;

[0015] The PCB board contains circuitry, including detection circuitry, which includes:

[0016] A first resonant amplifier circuit is used to determine the electromagnetic signal of the first coil. The first resonant amplifier circuit includes a first inductor, a first resistor, and a first capacitor, wherein the first inductor and the first resistor are derived from the first coil connected to the circuit.

[0017] The signal conditioning module is used to condition the electromagnetic signal from the first resonant amplifier circuit into a weak electrical signal;

[0018] The processor is used to process the weak electrical signal from the signal conditioning module to determine a first detection value. The first detection value is used to determine whether the object to be tested placed in the containment cavity is a foreign object, so that the aerosol generating device is in a heated state or a non-heated state.

[0019] In some embodiments, the aerosol generating device includes a second coil; the circuit includes a first switch and a heating circuit, one end of the first switch is connected to the second coil, and the other end of the first switch is connected to a detection circuit or a heating circuit.

[0020] In some embodiments, the aerosol generating device satisfies at least one or more of the following conditions:

[0021] The first switch includes a single-pole double-throw switch or a transistor;

[0022] The first coil includes multiple coils, and along the length of the receiving cavity, one or more of the multiple coils are disposed above the second coil, and one or more of the multiple coils are disposed below the second coil;

[0023] The first resonant amplifier circuit includes multiple circuits, and each coil in the first coil is connected to each first resonant amplifier circuit.

[0024] The first coil includes two coils: a first upper coil and a first lower coil. The first upper coil is positioned above the second coil, and the first lower coil is positioned below the second coil.

[0025] The first coil and / or the second coil include planar coils and / or solenoid coils;

[0026] The PCB board includes a flexible PCB board, on which a first coil and a second coil are printed.

[0027] Thirdly, this application also provides an aerosol generating apparatus, comprising: a receiving cavity for containing aerosol generating articles;

[0028] Second coil;

[0029] The PCB board contains a circuit, including a detection circuit, a heating circuit, and a first switch. One end of the first switch is connected to a second coil, and the other end of the first switch is connected to either the detection circuit or the heating circuit. The detection circuit includes:

[0030] The second resonant amplifier circuit is used to determine the electromagnetic signal of the second coil. The second resonant amplifier circuit includes a second inductor, a second resistor, and a second capacitor. The second inductor and the second resistor are derived from the connected second coil. The electromagnetic signal is used to determine whether the object to be tested placed in the receiving cavity is a foreign object, so that the aerosol generating device is in a heated or unheated state.

[0031] According to the aerosol generating device provided in this application, the electromagnetic signal of the second coil can be determined. This electromagnetic signal can be used to determine whether the object to be tested is a foreign object, so that the aerosol generating device is in a heating state or a non-heating state. This avoids the abnormal start-up of the heating system of the aerosol generating device due to the insertion of a foreign object containing a metal body when the aerosol generating device is not used normally. This avoids the risk of local overheating, short circuit or component burnout caused by incorrect energy transfer to the foreign metal body. It realizes the upgrade of the aerosol generating device from "circuit safety" to "electromagnetic safety", and provides a guarantee for the reliability and user safety of electromagnetic induction aerosol generating devices. At the same time, the second coil detection and heating functions can be reused through the first switch, ensuring that the structure of the smoking device is compact and simplified. Attached Figure Description

[0032] Figure 1 This application illustrates a flow chart of a detection method for an aerosol generating device according to some embodiments thereof. Figure 1 ;

[0033] Figure 2 This application illustrates a flow chart of a detection method for an aerosol generating device according to some embodiments thereof. Figure 2 ;

[0034] Figure 3 This application illustrates a flow chart of a detection method for an aerosol generating device according to some embodiments thereof. Figure 3 ;

[0035] Figure 4 This application illustrates a flow chart of a detection method for an aerosol generating device according to some embodiments thereof. Figure 4 ;

[0036] Figure 5 This application illustrates a flow chart of a detection method for an aerosol generating device according to some embodiments thereof. Figure 5 ;

[0037] Figure 6 A schematic diagram of a circuit for an aerosol generating apparatus according to some embodiments of this application is shown. Figure 1 ;

[0038] Figure 7 A block diagram of a detection circuit provided according to some embodiments of this application is shown. Figure 1 ;

[0039] Figure 8 A block diagram of a detection circuit provided according to some embodiments of this application is shown. Figure 2 ;

[0040] Figure 9This diagram illustrates a first series resonant amplifier circuit according to some embodiments of this application;

[0041] Figure 10 This diagram illustrates a first parallel resonant amplifier circuit according to some embodiments of this application;

[0042] Figure 11 This illustration shows a cavity in an empty state according to some embodiments of this application. Figure 1 ;

[0043] Figure 12 This illustration shows a cavity in an empty state according to some embodiments of this application. Figure 2 ;

[0044] Figure 13 This illustration shows a cavity in an empty state according to some embodiments of this application. Figure 3 ;

[0045] Figure 14 A schematic diagram of an aerosol generating article for an aerosol generating apparatus according to some embodiments of this application is shown;

[0046] Figure 15 This illustration shows a cavity in an empty state according to some embodiments of this application. Figure 4 ;

[0047] Figure 16 This illustration shows a cavity containing a test object according to some embodiments of the present application. Figure 1 ;

[0048] Figure 17 This illustration shows a cavity containing a test object according to some embodiments of the present application. Figure 2 ;

[0049] Figure 18 This illustrates a mutual inductive coupling model between a detection coil and a heating element according to some embodiments of this application;

[0050] Figure 19a This invention illustrates a planar spiral detection coil according to some embodiments of the present application;

[0051] Figure 19b This illustrates a planar rectangular detection coil according to some embodiments of this application;

[0052] Figure 19c This invention illustrates a cylindrical solenoid-type detection coil according to some embodiments of the present application;

[0053] Figure 19d This illustration shows a short dipole pair spiral detection coil according to some embodiments of this application;

[0054] Figure 20 This diagram illustrates the initial determination of standard detection values ​​according to some embodiments of this application;

[0055] Figure 21 A schematic diagram illustrating calibration triggered by standard detection values ​​according to some embodiments of this application is shown;

[0056] Figure 22 This application illustrates a flow chart of a detection method for an aerosol generating device according to some embodiments thereof. Figure 6 . Detailed Implementation

[0057] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. Although the description of this utility model will be presented in conjunction with preferred embodiments, this does not mean that the features of this utility model are limited to this embodiment. On the contrary, the purpose of describing the utility model in conjunction with the embodiments is to cover other options or modifications that may be derived based on the claims of this utility model. To provide a deep understanding of this utility model, many specific details will be included in the following description. This utility model may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of this utility model, some specific details will be omitted in the description. It should be noted that, without conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0058] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0059] In the description of this embodiment, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment based on the specific circumstances.

[0060] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0061] Firstly, reference Figure 1 This application provides a detection method for an aerosol generating device. Combined with... Figures 11-17The aerosol generating device includes a receiving cavity 1 for containing the aerosol-generating product. Preferably, the aerosol-generating product is an electromagnetic induction type aerosol-generating product. The aerosol generating device includes a first coil 2. The detection method includes the following steps:

[0062] Step S10': Determine the first standard detection value corresponding to the first coil 2 when the accommodating cavity 1 is in an empty cavity state or when the standard aerosol generating product is contained;

[0063] Step S20': When the object to be tested is placed into the receiving cavity 1, determine the first current detection value corresponding to the first coil 2;

[0064] Step S30': Based on the first standard detection value and the first current detection value, determine whether the object to be tested is a foreign object, so that the aerosol generating device is in a heated state or a non-heated state.

[0065] It should be noted that "standard aerosol generating articles" can be understood as one or more aerosol generating articles used in conjunction with the aerosol generating device. "Foreign objects" can be understood as non-standard aerosol generating articles. That is, other articles besides standard aerosol generating articles, such as non-aerosol generating articles including metal bodies (such as ear picks, paper clips, or tweezers), or one or more aerosol generating articles not used in conjunction with the aerosol generating device.

[0066] According to the detection method for an aerosol generating device provided in this application, it is possible to determine whether the object to be tested is a foreign object based on a first standard detection value and a first current detection value, thereby enabling the aerosol generating device to be in a heating or non-heating state. That is, the heating function of the aerosol generating device can be controlled to be turned on or off based on the foreign object detection result, avoiding abnormal startup of the heating system of the aerosol generating device due to the insertion of a foreign object containing a metal body under abnormal use conditions. This avoids the risk of local overheating, short circuit, or component burnout caused by incorrect energy transfer to the foreign metal body, achieving an upgrade from "circuit safety" to "electromagnetic safety" for the aerosol generating device, and providing assurance for the reliability and user safety of electromagnetic induction aerosol generating devices.

[0067] In some embodiments, reference Figure 6 and combined Figures 11-16 The aerosol generating device includes a second coil 3, which can be connected to both a heating circuit and a detection circuit. The first coil 2 and the second coil 3 are arranged along the length of the receiving cavity (e.g., the first coil 2 and the second coil 3 may partially overlap or not overlap in the length direction). When the aerosol generating device is in a non-heating state, the first coil 2 and the second coil 3 are respectively connected to the detection circuit. (Reference) Figure 2 The detection methods include:

[0068] Step S10: Determine the first standard detection value corresponding to the first coil 2 and the second standard detection value corresponding to the second coil 3 when the accommodating cavity 1 is in an empty cavity state or when it is accommodating the standard aerosol generating product.

[0069] Step S20: When the object to be tested is placed into the receiving cavity 1, the first current detection value corresponding to the first coil 2 and the second current detection value corresponding to the second coil 3 are determined respectively.

[0070] Step S30: Based on the first standard detection value, the second standard detection value, the first current detection value, and the second current detection value, determine whether the object to be tested is a foreign object, so that the aerosol generating device is in a heated state or a non-heated state.

[0071] Since both the first coil 2 and the second coil 3 can be connected to the detection circuit, and the first coil 2 and the second coil 3 are along the length of the receiving cavity (e.g., Figure 11 The Z-direction setting shown increases the range of foreign object detection, thereby improving the accuracy of foreign object detection.

[0072] In some embodiments, reference Figure 3 Step S30, based on the first standard detection value, the second standard detection value, the first current detection value, and the second current detection value, determines whether the object to be tested is a foreign object, so as to put the aerosol generating device into a heated state or a non-heated state, including the following steps:

[0073] Step S31: Determine whether the first detection difference value between the first current detection value and the first standard detection value falls within the first detection range;

[0074] Step S32: If the first detection difference value does not fall within the first detection range, the object to be tested is determined to be a foreign object, so that the aerosol generating device is in a non-heating state.

[0075] Step S33: If the first detection difference value falls within the first detection range, determine whether the second detection difference value between the second current detection value and the second standard detection value falls within the second detection range, so as to determine whether the object to be tested is a foreign object, so as to put the aerosol generating device in a heated state or a non-heated state.

[0076] According to the above detection method, if the first detection difference value does not fall within the first detection range, the object to be tested is directly determined to be a foreign object, and the determination is no longer based on the second detection difference value; if the first detection difference value falls within the first detection range, the determination is further based on the second detection difference value, thereby improving the detection efficiency while ensuring the accuracy of foreign object detection.

[0077] In some embodiments, reference Figure 4Step S33, determining whether the second detection difference value between the second current detection value and the second standard detection value falls within the second detection range, in order to determine whether the analyte is a foreign object, so that the aerosol generating device is in a heated or unheated state, includes the following steps:

[0078] Step S331: If the second detection difference value does not fall within the second detection range, determine that the analyte is a foreign object, and then put the aerosol generating device in a non-heating state; and / or,

[0079] Step S332: If the second detection difference value falls within the second detection range, the test object is determined to be a standard aerosol product, so that the aerosol device is in a heated state.

[0080] In another embodiment, reference Figure 5 Step S33, determining whether the second detection difference value between the second current detection value and the second standard detection value falls within the second detection range, in order to determine whether the analyte is a foreign object, so that the aerosol generating device is in a heated or unheated state, includes the following steps:

[0081] Step S331': If the second detection difference value does not fall within the second detection range, determine that the analyte is a foreign object, and then put the aerosol generating device in a non-heating state; and / or,

[0082] Step S332': If it is determined that the second detection difference value falls within the second detection range, determine whether the second detection difference value falls within the third detection range, wherein the second detection range covers the third detection range;

[0083] Step S333': If the second detection difference value does not fall within the third detection range but falls within the second detection range, the user determines whether the object to be tested is a foreign object, and then sets the aerosol generating device to a heated or unheated state. It should be noted that the user can determine whether the object to be tested is a foreign object through the operating interface on the aerosol generating device; and / or,

[0084] Step S334': If the second detection difference value falls within the third detection range, the test substance is determined to be a standard aerosol generating product, and the aerosol generating device is put into a heating state.

[0085] In other words, when making a determination based on the second detection difference value, in some embodiments, the second detection difference value may only be compared with the second detection range: (a) if the second detection difference value does not fall within the second detection range, the analyte is determined to be a foreign object; (b) if the second detection difference value falls within the second detection range, the analyte is determined to be a standard aerosol generating product. In other embodiments, the second detection difference value may be compared with both the second detection range and the third detection range: (a) if the second detection difference value does not fall within the second detection range, the analyte is determined to be a foreign object; (b) if the second detection difference value does not fall within the third detection range but falls within the second detection range, the user determines whether the analyte is a foreign object; (c) if the second detection difference value falls within the third detection range, the analyte is determined to be a standard aerosol generating product. It should be noted that the "second detection range" in some embodiments and in others may be the same or different.

[0086] In some embodiments, the first detection difference value is the difference between the first current detection value and the first standard detection value, and the second detection difference value is the difference between the second current detection value and the second standard detection value. In other embodiments, the first detection difference value is the rate of change between the first current detection value and the first standard detection value, and the second detection difference value is the rate of change between the second current detection value and the second standard detection value.

[0087] In some embodiments, the detected value includes the resonant frequency. For example, the resonant frequency can be determined based on a resonant amplifier circuit. At resonance, the circuit impedance reaches its extreme value, and the voltage reaches its extreme value under constant current. By sweeping the frequency and measuring the resonant amplified voltage, the frequency at which the voltage extreme value occurs is the resonant frequency. Alternatively, the AC voltage and current waveforms can be directly measured. When the voltage and current reach the same phase, the circuit resonates. Signal processing and calculation are performed through a phase-locked loop to obtain the corresponding frequency, which is the resonant frequency.

[0088] In other embodiments, the detected value includes a voltage value. For example, the voltage value may be determined based on a resonant amplifier circuit. The resonant amplifier circuit will be described in detail below.

[0089] In some embodiments, where the first detection difference value is the difference between a first current detection value and a first standard detection value, and the second detection difference value is the difference between a second current detection value and a second standard detection value, the detection value includes a resonant frequency. For example, the absolute value of a first detection range is greater than or equal to 0 and less than 150 kHz; and / or, the absolute value of a second detection range is greater than or equal to 0 and less than 300 kHz; and / or, the absolute value of a third detection range is greater than or equal to 0 and less than 150 kHz. In other embodiments, the detection value includes a voltage value. For example, the absolute value of a first detection range is greater than or equal to 0 and less than 0.5 V; and / or, the absolute value of a second detection range is greater than or equal to 0 and less than 1 V; and / or, the absolute value of a third detection range is greater than or equal to 0 and less than 0.5 V.

[0090] In some embodiments, where the first detection difference value is the rate of change between a first current detection value and a first standard detection value, and the second detection difference value is the rate of change between a second current detection value and a second standard detection value, the detection value includes a resonant frequency. For example, the absolute value of a first detection range is greater than or equal to 0 and less than 5%; and / or, the absolute value of a second detection range is greater than or equal to 0 and less than 10%. In other embodiments, the detection value includes a voltage value. For example, the absolute value of a first detection range is greater than or equal to 0 and less than 17%; and / or, the absolute value of a second detection range is greater than or equal to 0 and less than 33%; and / or, the absolute value of a third detection range is greater than or equal to 0 and less than 17%.

[0091] Secondly, refer to Figure 6 and Figure 7 This application also provides a circuit for an aerosol generating device, including: a detection circuit, which includes: a first resonant amplifier circuit 10.

[0092] The first resonant amplifier circuit 10 is used to determine the electromagnetic signal of the first coil 2. This electromagnetic signal is used to determine whether the object under test is a foreign object, thus enabling the aerosol generating device to be in a heated or unheated state. The first resonant amplifier circuit 10 includes a first inductor, a first resistor, and a first capacitor. The first inductor and the first resistor originate from the connected first coil 2; in other words, the first coil 2, once connected, can be equivalent to a first inductance L. D and the first resistor R DAnd together with the first capacitor C, they form a resonant circuit. Exemplarily, the electromagnetic signal can be a voltage signal. The first coil 2 can be connected to the circuit through its two terminals. The voltage across the first coil 2 can be sampled by a voltage sampling circuit to obtain a voltage amplified signal for processing by the subsequent signal conditioning module. Alternatively, the electromagnetic signal can be a resonant frequency signal. Based on the resonant amplification circuit, the frequency corresponding to the extreme value of the voltage amplified signal, i.e., the resonant frequency, is determined for processing by the subsequent signal conditioning module. The electromagnetic signal can include the first standard detection signal corresponding to the first standard detection value and the first current detection signal corresponding to the first current detection value, as described in the first aspect of the method. The amplification circuit based on the resonant topology can amplify the small voltage signal of the first coil 2, thereby improving the accuracy of the detection result.

[0093] In some embodiments, the detection circuit may further include a signal conditioning module 20, which is used to condition the electromagnetic signal from the first resonant amplifier circuit 10 into a weak electrical signal. The weak electrical signal can be amplified, filtered, and shaped more precisely, thereby improving the sensitivity of the entire system; secondly, the weak electrical signal is less sensitive to external interference (such as electromagnetic interference), and therefore experiences less interference during transmission, helping to maintain signal integrity. Exemplarily, the signal conditioning module 20 may include a rectifier circuit and / or a filter circuit.

[0094] In some embodiments, the detection circuit may further include a processor 30, which processes the weak electrical signal from the signal conditioning module 20 to determine a first detection value (which may include a first standard detection value and a first current detection value). The first detection value is used to determine whether the object to be tested placed in the receiving cavity is a foreign object, so that the aerosol generating device is in the heated state or the unheated state. Exemplarily, the processor 30 may execute the method of any embodiment of the first aspect based on the weak electrical signal, which will not be described in detail here.

[0095] The circuit provided in this application for an aerosol generating device can determine its electromagnetic signal based on a first coil. This electromagnetic signal can be used for foreign object detection, avoiding the risk of abnormal activation of the heating system of the aerosol generating device due to the insertion of foreign objects containing metal bodies under abnormal use, which could lead to local overheating, short circuit, or component burnout. This upgrades the aerosol generating device from "circuit safety" to "electromagnetic safety," providing assurance for the reliability and user safety of electromagnetic induction aerosol generating devices.

[0096] In some embodiments, the processor 30 may be a microcontroller. Specifically, the processor 30 may be an STM32F030C8T6 microcontroller. It is a microcontroller based on the ARM Cortex-M0 core manufactured by STMicroelectronics, which has advantages such as high cost-effectiveness, low power consumption and rich peripherals.

[0097] In some embodiments, continue to refer to Figure 6 The circuit for the aerosol generating device further includes a first switch K1 and a heating circuit. The aerosol generating device also includes a second coil 3, with one end of the first switch K1 connected to the second coil 3 and the other end connected to a detection circuit or a heating circuit. Exemplarily, the first switch K1 includes a single-pole double-throw switch, and the second coil 3 switches between a "detection coil" and a "heating coil" via the single-pole double-throw switch. The single-pole double-throw switch can be an Analog Devices ADG824 model single-pole double-throw switch. In other embodiments, the first switch K1 includes a transistor, exemplarily a power transistor or a combination thereof. In other words, when the aerosol generating device is in a non-heating state, the second coil 3 is connected to the detection circuit via the first switch K1, at which point the second coil 3 functions as a detection coil; when it is determined that the analyte is not a foreign object, the first switch K1 is controlled to switch to the heating circuit, and the second coil 3 is connected to the heating circuit, so that the heating component located within the standard aerosol generating article (such as...) Figure 14 (As shown) When heating occurs, the aerosol generating device is in heating mode, and the second coil 3 acts as a heating coil. After heating is complete, the aerosol generating device is in non-heating mode, and the first switch K1 is controlled to switch back to the detection circuit, and the second coil 3 is reconnected to the detection circuit. Through the first switch K1, the detection and heating functions of the second coil 3 can be reused, improving the accuracy of foreign object detection while ensuring the compact structure of the smoking device.

[0098] In some embodiments, reference Figure 8The detection circuit further includes a second resonant amplifier circuit 40. The other end of the first switch K1 is connected to the second resonant amplifier circuit 40 to determine the electromagnetic signal of the second coil 3. Exemplarily, the electromagnetic signal may include a voltage signal or a resonant frequency signal, and may include the second standard detection signal corresponding to the second standard detection value and the second current detection signal corresponding to the second current detection value in the first aspect of the method described above. The second resonant amplifier circuit includes a second inductor, a second resistor, and a second capacitor, wherein the second inductor and the second resistor originate from the connected second coil 3. The signal conditioning module 20 is used to condition the electromagnetic signal from the second resonant amplifier circuit 40 into a weak electrical signal for processing by the processor 30. The processor 30 processes the weak electrical signal from the signal conditioning module 20 to determine a second detection value (which may include a second standard detection value and a second current detection value), the second detection value being used to determine whether the object to be tested placed in the receiving cavity is a foreign object, so that the aerosol generating device is in a heated or unheated state.

[0099] In some embodiments, reference Figure 9 The first resonant amplifier circuit includes a first series resonant amplifier circuit, which includes an AC voltage U. AC First inductor L D First resistor R D The system consists of a first capacitor C, a fourth resistor R1, and an amplifying element A. One end of the fourth resistor R1 is connected to the AC voltage U. AC The fourth resistor R1 is connected to the inverting input terminal of the amplifying element A and one end of the first coil 2. The other end of the first coil 2 is connected to the output terminal of the amplifying element A through the first capacitor C. The non-inverting input terminal of the amplifying element A is grounded. For example, the amplifying element A can be an amplifier (e.g., an operational amplifier).

[0100] In some embodiments, reference Figure 10 The first resonant amplifier circuit includes a first parallel resonant amplifier circuit, which includes an AC voltage U. AC First inductor L D First resistor R D The first capacitor C, the fourth resistor R1, the amplifying element A, and the feedback resistor R f Among them, the first coil 2, the first capacitor C, and the feedback resistor R f They are connected in parallel, and one end of the fourth resistor R1 is connected to the AC voltage U. AC The other end of the fourth resistor R1 is connected to the inverting input terminal of the amplifier element A and the feedback resistor R. fOne end of the first capacitor C, one end of the first coil 2, and the other end of the first coil 2 are connected together. The other end of the first coil 2 is connected to the output terminal of the amplifying element A, and the non-inverting input terminal of the amplifying element A is grounded. For example, the amplifying element A can be an amplifier (e.g., an operational amplifier). This is achieved by setting the feedback resistor R... f This method feeds a portion of the amplifier's output signal back to the amplifier's inverting input, creating a negative feedback loop within the amplifier. This stabilizes the amplifier's gain, prevents the amplifier from operating in the saturation or nonlinear region, and improves the circuit's operational stability.

[0101] In some embodiments, reference Figure 9 and Figure 10 The first resonant amplifier circuit also includes diode D. e Third resistor R e and the third capacitor C e Among them, diode D e The positive terminal of diode D is connected to the output terminal of amplifying element A. e The negative terminal and the third resistor R e One end, the third capacitor C e One end is connected to the third resistor R. e With the third capacitor C e Parallel connection, third resistor R e The other end, the third capacitor C e The other end is grounded. Because diode D e It has unidirectional conduction, preventing signal reverse transmission and avoiding interference to the amplifier and subsequent circuits. Secondly, a third resistor R is connected in parallel. e With the third capacitor C e This ensures the amplifier operates normally and stably. The detected value can be the first inductance L. D and the first resistor R D The AC voltage detection value (e.g., amplitude) across the series branch (i.e., the equivalent circuit part after the first coil 2 is connected); or it can be the third resistor R. e and the third capacitor C e The DC voltage detection value at both ends of the parallel branch is proportional to the AC voltage detection value mentioned above.

[0102] The specific structure of the second resonant amplifier circuit 40 can be referred to the above description of the first resonant amplifier circuit 10, and will not be repeated here. It should be noted that the first resonant amplifier circuit 10 and the second resonant amplifier circuit 40 can be respectively set with AC voltage U. AC (Signal source) can also share the same AC voltage U AC (Signal source).

[0103] The above two resonant amplifier circuits (such as Figure 9The first series resonant amplifier circuit shown and Figure 10 The first parallel resonant amplifier circuit shown can determine whether the object under test is a foreign object by the difference between the voltage amplification signal or the resonant frequency signal. The difference is that when the circuit is adjusted to the resonant condition, the total impedance of the series resonant amplifier circuit reaches its minimum value at the resonant frequency, so the current through the circuit reaches its maximum value at resonance; the total impedance of the parallel resonant amplifier circuit reaches its maximum value at the resonant frequency, so the current through the circuit reaches its minimum value at resonance.

[0104] Series resonant amplifier circuits offer high sensitivity to impedance changes, effectively reflecting minute impedance differences in the device under test (DUT), making them more suitable for precision testing of DUTs with high performance requirements. For higher detection accuracy (e.g., judging minute differences), a series resonant amplifier circuit is preferred. Parallel resonant amplifier circuits provide more stable signal amplitude response and stronger anti-interference performance, making them suitable for batch testing and complex testing environments. For more complex testing environments (e.g., strong interference signals), a parallel resonant amplifier circuit is preferred.

[0105] It should be noted that although this application only shows embodiments of series resonant amplifier circuits and parallel resonant amplifier circuits, those skilled in the art will understand that other composite resonant circuits can also be used to achieve this.

[0106] In some embodiments, AC voltage U AC The AC voltage source chip is provided. Specifically, the AC voltage source chip can be the AD9851BRSZRL chip. It is a Direct Digital Synthesizer (DDS) chip manufactured by Analog Devices, Inc. (ADI). It is powerful and highly integrated, capable of generating high-precision sine wave signals, and can output sine waves from 3MHz to 10MHz with a step accuracy of 1kHz.

[0107] Thirdly, refer to Figure 11 This application also provides an aerosol generating device (not shown in the figure), comprising: a receiving cavity 1 for receiving an electromagnetic induction type aerosol generating article, wherein the aerosol generating article is provided with a heating element (such as...). Figure 14 (as shown); a first coil 2 and a second coil 3, the second coil 3 being able to be connected to a heating circuit to cause the heating element to heat up; a PCB board (not shown in the figure), the PCB board having a circuit for an aerosol generating device as in any embodiment of the second aspect.

[0108] It should be noted that the "heating component" can be understood as a component that rapidly heats the tobacco matrix or other atomizable materials through eddy current action. Preferably, at least a portion of the heating component can be placed within the aerosol-generating article. The aerosol-generating article can be a cigarette-shaped smoking article, including but not limited to tobacco sheets, tobacco particles, shredded tobacco, reconstituted tobacco, and other tobacco products that can be heated by an aerosol-generating device to generate an aerosol for the user to inhale. Further, the "heating component" is preferably a part of the aerosol-generating article, that is, the aerosol-generating article includes the "heating component".

[0109] Furthermore, the second coil 3 can be connected to both the heating circuit and the detection circuit, and the first coil 2 and the second coil 3 are along the length of the receiving cavity (e.g., Figure 11 The Z-direction setting (as shown) means that the two can be non-overlapping or partially overlapping in the length direction. This setting can expand the detection range while ensuring the compactness of the instrument structure.

[0110] In some embodiments, the first coil 2 includes a plurality of coils along the length direction of the receiving cavity 1 (e.g., ...). Figure 11 (As shown in the Z direction), several coils of the plurality of coils are positioned above the second coil, and several other coils of the plurality of coils are positioned below the second coil 3. The first resonant amplifier circuit 10 includes a plurality of coils, and each coil of the first coil 2 is connected to a different first resonant amplifier circuit.

[0111] In some embodiments, the first coil 2 and / or the second coil 3 include planar coils and / or solenoid coils. In other words, the first coil 2 and the second coil 3 can both be planar coils (e.g., Figure 12 (as shown) or similar solenoid coils (such as...) Figure 11 (as shown); or, the first coil 2 and the second coil 3 are of different types, such as Figure 13 As shown, the first coil 2 can be a planar coil, and the second coil 3 can be a solenoid coil; or, as... Figure 15 As shown, when the first coil 2 includes multiple coils, the first coil can include a planar coil and a solenoid coil. It should be noted that the number of first coils 2 can be one or more, along the length of the receiving cavity (e.g., Figure 11 (As shown in the Z direction), the first coil 2 and the second coil 3 can be connected to each other, spaced apart, or partially overlapped; no specific limitation is made here.

[0112] In some embodiments, reference Figure 17 The number of first coils 2 is one, and it can be positioned above the second coil 3, that is, along the length direction (e.g., Figure 11(As shown in the Z direction) The first coil 2 is positioned near the opening of the receiving cavity for inserting the aerosol-generating article, close to the second coil 3. When the dimension of the object to be tested 4 along its length is larger than that of the receiving cavity 1, the object to be tested 4 (e.g., a metal tweezer or a metal ear pick) can be detected using only the first coil 2 positioned at the top.

[0113] For example, after the aerosol generating device is powered on (e.g., turned on), the AC voltage source chip (e.g., AD9851 chip) performs a frequency sweep on the first coil. For instance, the frequency of the frequency sweep is 3 to 10 MHz, in 10 kHz increments, and the voltage signal corresponding to each frequency point is recorded. The frequency corresponding to the minimum voltage signal is used as the first background detection value f. bg-top When metal tweezers enter the receiving cavity 1, the first coil 2 at the top is affected by the metal, causing a change in its equivalent inductance and thus a shift in its resonant frequency. At this time, the current first detection value f of the first coil 2 is determined by the detection circuit. exam-top Based on the first current detection value f exam-top Compared with the first background detection value f bg-top The difference value, for example, the difference Δf = f exam-top -f bg-top The absolute value of the aerosol generator falls within the absolute value of the first detection range [0, 150) kHz to determine whether the test object 4 is a foreign object, thus keeping the aerosol generator in a non-heating state and avoiding abnormal heating of the aerosol generator due to the insertion of foreign objects, which could cause unnecessary damage to the equipment and injury to the user. When the first coil 2 is set at the top, the first standard detection value f corresponding to the first coil 2 under the containment cavity 1 containing the standard aerosol generating product is determined. std-top The first standard detection value f corresponding to the first coil when the cavity 1 is in an empty state. bg-top Approximately, therefore, it can be based on the first current detection value f exam-top The first standard test value f of the standard aerosol generating product contained in the receiving cavity 1. std-top The difference value (e.g., the difference) or based on the first current detection value f exam-top The first standard detection value f of cavity 1 in the cavity state bg-top The difference value (e.g., the difference) is used to determine whether the test object 4 is a foreign object. Besides determining whether the test object 4 is a foreign object based on the resonant frequency of the detection value, it can also be determined based on the voltage value of the detection value. For example, a first standard detection value V can be determined by the detection circuit. std-top and the first current detection value V exam-top And based on the first current detection value V exam-top Compared with the first standard test value V std-top The difference, such as the rate of change. Whether the absolute value falls within the absolute value of the first detection range [0, 17)% determines whether the test object 4 is a foreign object. As mentioned above, when the first coil 2 is set at the top, since the receiving cavity 1 contains the standard aerosol generating product, the first standard detection value V corresponding to the first coil 2 is determined. std-top The first standard detection value V corresponding to the first coil when the cavity 1 is in an empty state. bg-top Approximately, therefore, it can also be based on the first current detection value V. exam-top Compared with the first standard test value V bg-top rate of change Determine whether test object 4 is a foreign object.

[0114] It should be noted that the "standard detection value" in this application (i.e., the detection value corresponding to the coil under the standard aerosol generating product in the receiving cavity or the detection value corresponding to the coil when the receiving cavity is empty) can be pre-stored before the aerosol generating device leaves the factory and does not need to be determined by the user; or it can be determined by the user after the aerosol generating device leaves the factory. For example, after the aerosol generating device is activated, the user can determine the detection value corresponding to the coil (e.g., the first coil 2) when the receiving cavity 1 is empty as the standard detection value through the operation interface and save it to the aerosol generating device. Alternatively, the user can determine the detection value corresponding to the coil under the standard aerosol generating product in the receiving cavity 1 by inserting one or more standard aerosol generating products into the receiving cavity 1 and save it as the standard detection value to the aerosol generating device. Or, the user can manually adjust or input the standard detection value through the operation interface, which is not specifically limited here.

[0115] In other embodiments, the number of first coils 2 is one, which can be disposed below the second coil 3, i.e., along the length direction (e.g., ...). Figure 11 (As shown in the Z direction) The first coil 2 is positioned away from the opening of the receiving cavity 1 for inserting the aerosol-generating article, away from the second coil 3. Similar to the case where the first coil 2 is positioned at the top, when the first coil 2 is positioned at the bottom of the receiving cavity 1, it is possible to determine whether the test object 4 is a foreign object based on the difference (e.g., difference or rate of change) between the first current detection value and the first standard detection value of the receiving cavity 1 in an empty state, or the difference (e.g., difference or rate of change) between the first current detection value and the first standard detection value of the standard aerosol-generating article contained in the receiving cavity 1. This will not be elaborated further here. When the first coil 2 is positioned at the bottom of the receiving cavity 1, small metal pieces, paperclips (such as...) can be detected. Figure 16Foreign objects (as shown) fall into the receiving cavity 1. When the first coil 2 and the second coil 3 are different types of coils (e.g., planar coil or solenoid coil), the first coil 2 can also be located in the middle of the receiving cavity 1. When the first coil 2 is located at the bottom of the receiving cavity 1, for example, the absolute value of the first detection range can be [0, 150) kHz.

[0116] In other embodiments, reference is made to Figures 11-13 The first coil 2 includes two coils: a first upper coil and a first lower coil. The first upper coil is positioned above the second coil 3, and the first lower coil is positioned below the second coil 3. The first upper coil, the first lower coil, and the second coil 3 can be connected to their respective resonant amplifier circuits to determine the electromagnetic signal corresponding to each coil. The second coil can also be switched from being connected to a detection circuit to being connected to a heating circuit via a first switch K1, causing the heating element to heat up and the aerosol to be in a heated state.

[0117] For example, when the accommodating cavity 1 contains a standard aerosol generating article, an AC signal at the resonant frequency of the standard aerosol generating article state is applied to the detection coils (e.g., the first coil 2 and the second coil 3), and the standard detection values ​​of the detection circuits corresponding to the top coil, middle coil, and bottom coil are measured respectively, for example, the standard voltage value V. std-top V std-mid V std-bottom For example, the first coil 2 includes a top coil and a bottom coil, and the second coil 3 includes a middle coil. As mentioned above, the standard detection value can be predetermined and stored in the aerosol generating device before leaving the factory, or it can be determined and stored by the user-instructed detection circuit after leaving the factory, or it can be directly input and stored by the user. Alternatively, when the receiving cavity 1 is in an empty state, an AC signal at the resonant frequency is applied to the detection coil, and the standard detection values ​​of the detection circuits corresponding to the top coil, middle coil, and bottom coil are measured respectively. For example, the standard voltage value V bg-top V bg-mid V bg-bottom This leads to the correction of the standard test value of the middle coil based on a preset correction term. The top coil (upper coil) can be understood as the coil along its length (e.g., along its length). Figure 11 The area (in the Z direction as shown) no more than 10mm from the insertion port of the receiving cavity 1; the bottom coil (lower coil) can be understood as the area along the length direction (e.g., Figure 11 The area (in the Z direction as shown) is no more than 5 mm from the bottom of cavity 1; the middle coil can cover the entire area.

[0118] For example, refer to Figure 20When using the aerosol generator for the first time, after powering on, the user should measure the standard detection values ​​(or "cavity reference measurement") of the top coil (upper coil) and / or bottom coil (lower coil) in the empty cavity 1, and save the standard detection values ​​to the aerosol generator's memory. Then, insert a standard aerosol generating product (or "standard cartridge") into the cavity 1, measure the standard detection value of the middle coil in the cavity 1 below the standard aerosol generating product (or "standard value calibration"), and save it to the aerosol generator's memory. Alternatively, insert a standard aerosol generating product (or "standard cartridge") into the cavity 1, measure the standard detection values ​​of the upper and / or bottom coils and the middle coil in the cavity 1 below the standard aerosol generating product (or "standard value calibration"), and save them to the aerosol generator's memory. Combined with... Figure 21 As shown, users can also periodically maintain the standard detection values, i.e., remeasure the standard detection values ​​of the top coil (upper coil) and / or bottom coil (lower coil) in the empty cavity 1, and then update the remeasured standard detection values ​​to the memory. When the user replaces a different type of standard aerosol generating product (standard cartridge), the standard detection value of the middle coil under the replaced standard aerosol generating product in the cavity 1 is remeasured and updated to the memory as the standard detection value for the next foreign object detection; or when the user replaces a different type of standard aerosol generating product (standard cartridge), the standard detection values ​​of the upper and / or bottom coils and the middle coil under the replaced standard aerosol generating product in the cavity 1 are remeasured and updated to the memory as the standard detection values ​​for the next foreign object detection. After each standard detection value update, the detection range or detection threshold (the detection threshold is the upper limit of the detection range) can be updated to improve the accuracy of the detection.

[0119] After the test object 4 is placed in the receiving cavity 1, an AC signal at the resonant frequency of the product state generated by a standard aerosol is applied to the detection coils (e.g., the first coil 2 and the second coil 3). The current detection values ​​of the detection circuits corresponding to the top coil, middle coil, and bottom coil are detected respectively, for example, the current voltage value V. exam-top V exam-mid V exam-bottom .

[0120] Based on the difference (e.g., rate of change) between the current detected value (e.g., current voltage value) and the standard detected value (e.g., standard voltage value), it is determined whether the test object 4 is a foreign object. For example, the rate of voltage change can be determined using the following formula:

[0121]

[0122] In formula (1), δ exam-iV represents the rate of change of voltage at position i corresponding to the detection coil. exam-i This represents the current voltage value corresponding to the detection coil at position i, V. std-i This indicates the standard voltage value corresponding to the detection coil at position i, where i represents the top, middle, and bottom.

[0123] In some embodiments, when the voltage change rate δ exam-i If the object does not fall within the detection range at the corresponding location, the object to be tested 4 is determined to be a foreign object; when the voltage change rate δ exam-i When the sample falls into the detection range at the corresponding location, it is determined that the sample 4 is a standard aerosol generating product, or the user determines whether it is the sample 4.

[0124] In other embodiments, the voltage change rate δ corresponding to the detection coil at the top position or the detection coil at the bottom position is determined respectively. exam-i Whether it falls within the first detection range (e.g., the absolute value of the first detection range is greater than or equal to 0 and less than 17%). The rate of voltage change δ of the detection coil at the top position or the detection coil at the bottom position. exam-i If the object does not fall within the first detection range, the object to be tested 4 is determined to be a foreign object. The voltage change rate δ at the top or bottom detection coil is determined by... exam-i If the voltage falls within the first detection range, determine the voltage change rate δ corresponding to the detection coil at the middle position. exam-mid Whether it falls within the scope of the second detection.

[0125] Determining the voltage change rate δ exam-mid If the sample 4 does not fall within the second detection range (e.g., the absolute value of the second detection range is greater than or equal to 0 and less than 33%), the sample 4 is determined to be a foreign object; the voltage change rate δ is then determined. exam-mid If the voltage falls within the second detection range, determine the voltage change rate δ. exam-mid Whether it falls within the third detection range (e.g., the absolute value of the third detection range is greater than or equal to 0 and less than 17%).

[0126] Determining the voltage change rate δ exam-mid If the sample falls within the third detection range, analyte 4 is determined to be a standard aerosol-generating product; the voltage change rate δ is then determined. exam-mid If the object falls within the second detection range but not the third detection range, the user can determine whether the object to be tested 4 is a foreign object through the operation interface.

[0127] In some other embodiments, unlike the above-described embodiments based on the rate of change, reference is made to... Figure 22The detection method can also be based on the difference. For example, after detection is initiated, the top coil (upper coil) first performs detection to determine whether the absolute value of the difference between the resonant frequency of the current detection value and the standard detection value of the top coil is less than 150kHz, or whether the absolute value of the voltage difference is less than 0.5V, i.e., whether it falls within the first detection range. If the absolute value of the difference between the resonant frequency of the current detection value and the standard detection value of the top coil is greater than or equal to 150kHz, or the absolute value of the voltage difference is greater than or equal to 0.5V, i.e., not falling within the first detection range, the object under test is determined to be a foreign object, the protection is activated, heating is stopped, and the aerosol generating device is in a non-heating state. If the absolute value of the difference between the current detection value of the top coil and the standard detection value falls within the first detection range, the bottom coil (lower coil) further detects to determine whether the absolute value of the difference between the resonant frequency of the current detection value and the standard detection value of the bottom coil is less than 150kHz, or whether the absolute value of the voltage difference is less than 0.5V, i.e., whether it falls within the first detection range.

[0128] If the absolute value of the difference between the resonant frequency of the current detection value of the bottom coil and the standard detection value is greater than or equal to 150kHz, or the absolute value of the voltage difference is greater than or equal to 0.5V, i.e., it does not fall within the first detection range, the object to be tested is determined to be a foreign object, the protection is activated, heating is stopped, and the aerosol generating device is in a non-heating state; if the absolute value of the difference between the current detection value of the bottom coil and the standard detection value falls within the first detection range, the middle coil performs further detection.

[0129] If the absolute value of the difference between the resonant frequency of the current detection value and the standard detection value of the central coil is greater than or equal to 300kHz, or the absolute value of the voltage difference is greater than or equal to 1V, i.e., it does not fall within the second detection range, the object to be tested is determined to be a foreign object, the protection is activated, heating is stopped, and the aerosol generating device is in a non-heating state; if the absolute value of the difference between the resonant frequency of the current detection value and the standard detection value of the central coil is less than 300kHz, or the absolute value of the voltage difference is less than 1V, i.e., it falls within the second detection range, it is determined whether the absolute value of the difference between the resonant frequency of the current detection value and the standard detection value of the central coil is less than 150kHz, or whether the absolute value of the voltage difference is less than 0.5V.

[0130] If the absolute value of the difference between the resonant frequency of the current detection value of the central coil and the standard detection value is greater than or equal to 150kHz and less than 300kHz, or the absolute value of the voltage difference is greater than or equal to 0.5V and less than 1V, i.e., falling within the second detection range but not within the third detection range, the user must confirm whether to turn on heating via the operation interface. If the absolute value of the difference between the resonant frequency of the current detection value of the central coil and the standard detection value is less than 150kHz, or the absolute value of the voltage difference is less than 0.5V, i.e., falling within the third detection range, the test object is determined to be a standard aerosol generating product, heating is turned on, and the aerosol generating device is in heating mode.

[0131] In some embodiments, the PCB board includes a flexible PCB board and a non-flexible PCB board, which are electrically connected by leads. This configuration allows for a more compact structure of the aerosol generating device. Furthermore, a first coil and a second coil are printed on the flexible PCB board; a signal conditioning module and a processor are provided on the non-flexible PCB board. The non-flexible PCB board can be rectangular and nested within the components of the aerosol generating device, improving robustness and reliability.

[0132] In some embodiments, the first coil and / or the second coil are planar detection coils and are printed and fixed on a PCB board. The inventors have discovered that when the position of the object under test 4 changes slightly, the detection circuit can more sensitively sense the electromagnetic signal of the planar coil, thus improving the detection sensitivity of the aerosol generating device.

[0133] Fourthly, this application also provides an aerosol generating apparatus, comprising:

[0134] A containment cavity for holding aerosol-generating products;

[0135] Second coil;

[0136] The PCB board contains a circuit, including a detection circuit, a heating circuit, and a first switch. One end of the first switch is connected to a second coil, and the other end of the first switch is connected to either the detection circuit or the heating circuit. The detection circuit includes:

[0137] The second resonant amplifier circuit is used to determine the electromagnetic signal of the second coil. The second resonant amplifier circuit includes a second inductor, a second resistor, and a second capacitor. The second inductor and the second resistor are derived from the connected second coil. The electromagnetic signal is used to determine whether the object to be tested placed in the receiving cavity is a foreign object, so that the aerosol generating device is in a heated or unheated state.

[0138] According to the aerosol generating device provided in this application, the electromagnetic signal of the second coil can be determined. This electromagnetic signal can be used to determine whether the object to be tested is a foreign object, thereby setting the aerosol generating device to a heating or non-heating state. This avoids the abnormal activation of the heating system of the aerosol generating device due to the insertion of a foreign object containing a metal body under abnormal use, thus avoiding the risk of local overheating, short circuit, or component burnout caused by incorrect energy transfer to the foreign metal body. This upgrades the aerosol generating device from "circuit safety" to "electromagnetic safety," providing assurance for the reliability and user safety of electromagnetic induction aerosol generating devices. Simultaneously, the second coil detection and heating functions can be reused through the first switch, ensuring a compact and simplified structure for the smoking device. For detailed descriptions of each component and circuit, please refer to the descriptions in the first to third aspects above; further details will not be repeated here.

[0139] To improve the accuracy of voltage sensitivity, the inventors further studied the influencing factors of voltage change rate based on the mutual inductance coupling model.

[0140] The mutual inductive coupling model between the detection coil (e.g., the first coil and the second coil) and the metallic foreign object is as follows: Figure 18 As shown. According to Faraday's law of electromagnetic induction, when a block conductor is placed in an alternating magnetic field or moves in a fixed magnetic field, an induced current is generated within the conductor and closes within the conductor. Therefore, a metallic foreign object under the eddy current effect can be equivalent to a short-circuit loop current model, and in this case, the metallic foreign object can be equivalent to a coil. For example... Figure 18 As shown, L D R represents the self-inductance of the detection coil. D I represents the internal resistance of the detection coil. D L represents the current flowing through the detection coil. H R represents the self-inductance of a metallic foreign object. H I represents the internal resistance of a metallic foreign object. H M represents the current flowing through the metallic foreign object; M represents the mutual inductance between the metallic foreign object and the detection coil.

[0141] The induced electromotive force V on the detection coil mD It can be represented as:

[0142] V mD =jωMI H (2)

[0143] In formula (2), V mD The induced electromotive force on the detection coil is represented by j; the imaginary unit is represented by ω; the angular frequency of the alternating voltage is represented by M; and the mutual inductance between the metallic foreign object and the detection coil is represented by I. H This represents the current flowing through a metallic foreign object.

[0144] The total voltage V on the detection coilD It can be represented as:

[0145] V D =Z D I D +V mD =Z D I D +jωMI H (3)

[0146] In formula (3), V D Z represents the total voltage across the detection coil. D This indicates the impedance of the detection coil without it in place; I D V represents the current flowing through the detection coil. mD The induced electromotive force on the detection coil is represented by j; the imaginary unit is represented by ω; the angular frequency of the alternating voltage is represented by M; and the mutual inductance between the metallic foreign object and the detection coil is represented by I. H This represents the current flowing through a metallic foreign object.

[0147] Induced electromotive force V on a metallic foreign object mH It can be represented as:

[0148] V mH =jωMI D (4)

[0149] In formula (4), V mH ω represents the induced electromotive force on the metallic foreign object; j represents the imaginary unit; ω represents the angular frequency of the alternating voltage; M represents the mutual inductance between the metallic foreign object and the detection coil; I D This represents the current flowing through the detection coil.

[0150] The total voltage V on the metallic foreign object H It can be represented as:

[0151] V H =Z H I H +V mH =Z H I H +jωMI D (5)

[0152] Formula (5), V H Z represents the total voltage across the metallic foreign object. H Indicates the impedance of a metallic foreign object; I H V represents the current flowing through a metallic foreign object; mH ω represents the induced electromotive force on the metallic foreign object; j represents the imaginary unit; ω represents the angular frequency of the alternating voltage; M represents the mutual inductance between the metallic foreign object and the detection coil; I D This represents the current flowing through the detection coil.

[0153] Since the metallic foreign object is equivalent to a short-circuit loop current model, the total voltage V across the metallic foreign object is... H =0, that is, formula (5) can be expressed as:

[0154] V H =Z H I H +jωMI D =0,

[0155] Solve for I H ,Right now

[0156]

[0157] Substituting formula (6) into formula (3), we get:

[0158]

[0159] Simplifying, we get:

[0160]

[0161] Divide formula (11) by I D The equivalent impedance Z of the detection coil can be obtained. eq :

[0162]

[0163] Z D =R D +jωL D (9)

[0164] Substituting formula (9) into formula (8) and separating the real and imaginary parts, we get:

[0165]

[0166] The real part coefficient is also the proportionality coefficient of the change in the internal resistance of the detection coil. The imaginary part coefficient is also the proportionality coefficient of the change in self-inductance of the detection coil.

[0167] refer to Figure 9 and Figure 10 Due to the virtual short and virtual open characteristics of the amplifier, under AC voltage U AC Under certain conditions, the current flowing through the detection coil is the same whether there is no metal object (before the metal object is placed) or when a metal object is placed (after the metal object is placed). Therefore, the voltage change of the detection coil before and after the metal object is placed is equal to the impedance change. That is, the rate of change of impedance of the detection coil is equal to the rate of change of voltage δ, which can be expressed as:

[0168]

[0169] in,

[0170] In formula (11), δ represents the rate of change of impedance (or voltage change) of the detection coil; Z eq Z represents the equivalent impedance of the detection coil when a metallic foreign object is placed in it. D Q represents the impedance of the detection coil when no metallic foreign object is placed; D β represents the equivalent quality factor of the detection coil; β represents the proportional coefficient of the change in the internal resistance of the detection coil; α represents the proportional coefficient of the change in the self-inductance of the detection coil.

[0171] It can be seen that the impedance change rate (or voltage change rate) δ of the detection coil is related to the mutual inductance M of the heating element to the detection coil. Therefore, the impedance change rate (or voltage change rate) δ of the detection coil can be increased by increasing the mutual inductance M.

[0172] Referring to formula (1), voltage sensitivity In other words, by increasing the mutual inductance M, the impedance change rate (or voltage change rate) δ of the detection coil can be increased, thereby improving the accuracy of the voltage sensitivity S.

[0173] The inventors' research also revealed that designing a reasonable detection coil structure and size can improve the mutual inductance M. In other words, depending on the structure of the metallic foreign object being tested, the mutual inductance M can be increased by designing a corresponding detection coil, thereby improving the detection accuracy.

[0174] According to the law of electromagnetic induction, the induced current in a metallic foreign object is proportional to the strength of the induced magnetic field generated by the detection coil and its component perpendicular to the surface of the metallic foreign object. Therefore, increasing the strength of the induced magnetic field and its perpendicular component is a key factor in improving the mutual inductance M. Thus, the detection coil should be optimized in the following ways, including but not limited to: (1) The detection coil should adopt a multi-turn spiral structure design to increase the strength of the induced magnetic field. The number of turns and layers of the coil can be adjusted according to the detection accuracy requirements, but it should be designed in conjunction with the frequency and inductance value to avoid the resonant frequency being too low; (2) The plane (cross-section) of the detection coil should be as parallel as possible to the plane of the metallic foreign object (i.e., the plane with the largest cross-sectional area), while keeping the distance within a small range to increase the perpendicular component of the magnetic field; (3) The design of the detection coil should ensure that its center position is aligned with the center of the metallic foreign object, thereby optimizing the distribution of the perpendicular component of the magnetic field; (4) The diameter of the detection coil should match the size of the metallic foreign object to ensure that the induced magnetic field can completely cover the surface of the metallic foreign object; (5) In the design of a multi-layer spiral detection coil, the spacing between each layer should be minimized to improve the uniformity of the magnetic field and the coupling strength.

[0175] Figures 19a to 19d The following diagram illustrates the structure of a detection coil provided in some embodiments of this application. Figures 19a to 19d Specifically, depending on the structure of the metallic foreign object to be tested, the mutual inductance M can be increased by setting a corresponding detection coil on the detection device, thereby improving the detection accuracy.

[0176] For flat, thin-film, or large-area metallic foreign objects to be tested, methods such as... Figure 19a The planar spiral detection coil shown ( Figure 19a The difference between the left and right images is the number of turns; both have a planar spiral structure. Planar spiral coils can generate a uniform induced magnetic field within a planar region, with the largest vertical component, making them suitable for covering larger planar areas.

[0177] For elongated or rectangular cross-section metallic foreign objects to be tested, methods such as... Figure 19b The planar rectangular detection coil is shown. The induced magnetic field of the planar rectangular coil is mainly concentrated in the elongated region, making it suitable for matching with strip-shaped metal foreign objects.

[0178] For metallic foreign objects with columnar, annular, or axisymmetric structures, methods such as... Figure 19c The cylindrical solenoid-type detection coil shown is suitable for surrounding a cylindrical heating element to generate a strong vertical induced magnetic field, as the axial magnetic field strength of the cylindrical solenoid-type coil is the largest.

[0179] For dispersed, locally distinctive, or small metallic foreign objects (e.g., locally asymmetric metallic foreign objects, metallic foreign objects with complex geometric structures), methods such as... Figure 19d The diagram shows a short dipole pair spiral detection coil. Short dipole pair spiral coils can generate a strong localized magnetic field, making their distribution suitable for use with small, complex geometries, especially for localized detection.

[0180] Table 1 shows the planar spiral detection coil (e.g., ...). Figure 19a As shown) in a series resonant amplifier circuit (such as Figure 8 The parameter design example is shown in the figure.

[0181] Table 1 Planar spiral detection coil (e.g.) Figure 19a As shown) in a series resonant amplifier circuit (such as Figure 9 Parameter design example (shown)

[0182]

[0183]

[0184] It should be noted that the parameters of the detection coil, such as the self-inductance L... D and internal resistance R DThe self-inductance L can be determined through a combination of theoretical calculations, simulation analysis, and experimental measurements. Specifically, by utilizing the geometric dimensions and material properties of the detection coil, its self-inductance L is accurately calculated using electromagnetic simulation software. D Simultaneously, based on simulation analysis of the conductor's material resistivity and high-frequency skin effect, the internal resistance R was measured. D In addition, the actual electrical parameters of the detection coil were experimentally measured and verified using an impedance analyzer or LCR meter to ensure the accuracy of the values ​​in Table 1.

[0185] AC voltage (AC excitation source) U AC The selection of frequency f can be determined by the following principles: First, ensure that the excitation frequency matches the operating frequency range of the detection coil and the electromagnetic characteristics of the metal foreign object to be tested; second, improve the detection sensitivity while avoiding electromagnetic interference and excessive circuit loss caused by excessively high frequency.

[0186] The first capacitor C can be adjusted according to the AC excitation source U. AC The frequency f and the self-inductance L of the detection coil D The resonance matching is determined, and the specific formula can be found below.

[0187]

[0188] In AC voltage (AC excitation source) U AC The frequency f is 3MHz and the self-inductance L of the detection coil D With a capacitance of 10μH, the theoretical calculated value is approximately 177pF. Simultaneously, through simulation optimization and experimental debugging, the final capacitance value used was determined to achieve optimal resonant performance. The fourth resistor R1 can be adjusted according to the amplification factor of the required resonant amplifier circuit. In some embodiments, diode D... e The LRB521S-40T1G model can be used, with the third capacitor C. e The resistance of the first capacitor is 10kΩ, and the capacitance of the third capacitor Ce is 190nF.

[0189] The inventors' research also found that for induction heating products for cigarettes, the different sizes, materials, and shapes of metal foreign objects can be attributed to the different effects of the metal foreign objects on the equivalent impedance (including equivalent self-inductance and equivalent internal resistance) of the detection coil; while for induction heating products for cigarettes, in addition to the parameters of the metal foreign object itself (size, material, shape), the different positions of the metal foreign object relative to the detection coil can also be attributed to the effect of the metal foreign object on the equivalent impedance of the detection coil.

[0190] Although the present invention has been illustrated and described with reference to certain preferred embodiments, those skilled in the art should understand that the above description is a further detailed explanation of the present invention in conjunction with specific embodiments, and should not be construed as limiting the specific implementation of the present invention to these descriptions. Those skilled in the art can make various changes in form and detail, including some simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A circuit for an aerosol generating device, the aerosol generating device having a receiving cavity for accommodating an electromagnetic induction type aerosol generating product, characterized in that, The aerosol generating device includes a first coil, and the circuit includes: The detection circuit includes: A first resonant amplifier circuit is used to determine the electromagnetic signal of a first coil. The first resonant amplifier circuit includes a first inductor, a first resistor, and a first capacitor. The first inductor and the first resistor are derived from the first coil. The electromagnetic signal is used to determine whether the object to be tested placed in the receiving cavity is a foreign object, so that the aerosol generating device is in a heated or unheated state.

2. The circuit for an aerosol generating device as described in claim 1, characterized in that, include: The aerosol generating device further includes a first switch and a heating circuit, and a second coil. One end of the first switch is connected to the second coil, and the other end of the first switch is connected to the detection circuit or the heating circuit.

3. The circuit for an aerosol generating device as described in claim 2, characterized in that, The detection circuit includes a second resonant amplifier circuit, and the other end of the first switch is connected to the second resonant amplifier circuit to determine the electromagnetic signal of the second coil. The second resonant amplifier circuit includes a second inductor, a second resistor, and a second capacitor, wherein the second inductor and the second resistor are derived from the connected second coil.

4. An aerosol generating device, characterized in that, include: A containment cavity for containing products generated by electromagnetic induction aerosols; First coil; A PCB board, wherein the PCB board is provided with circuitry, the circuitry including a detection circuit, comprising: A first resonant amplifier circuit is used to determine the electromagnetic signal of the first coil. The first resonant amplifier circuit includes a first inductor, a first resistor, and a first capacitor. The first inductor and the first resistor are derived from the connected first coil. The electromagnetic signal is used to determine whether the object to be tested placed in the receiving cavity is a foreign object, so that the aerosol generating device is in a heated or unheated state.

5. The aerosol generating apparatus as described in claim 4, characterized in that, The aerosol generating device includes a second coil; the circuit includes a first switch and a heating circuit, one end of the first switch is connected to the second coil, and the other end of the first switch is connected to the detection circuit or the heating circuit.

6. The aerosol generating apparatus as described in claim 5, characterized in that, The first coil includes two coils: a first upper coil and a first lower coil. The first upper coil is positioned above the second coil, and the first lower coil is positioned below the second coil.

7. The aerosol generating apparatus as described in claim 5, characterized in that, The PCB board includes a flexible PCB board on which the first coil and the second coil are printed.

8. The aerosol generating apparatus as described in claim 5, characterized in that, The first coil and / or the second coil include planar coils and / or solenoid coils.

9. The aerosol generating apparatus as described in claim 7, characterized in that, The aerosol generating device must satisfy at least one or more of the following conditions: The first switch includes a single-pole double-throw switch or a transistor; The first coil includes a plurality of coils, and along the length of the receiving cavity, one or more of the plurality of coils are disposed above the second coil, and one or more of the plurality of coils are disposed below the second coil; The first resonant amplifier circuit includes multiple circuits, and each coil in the first coil is connected to each first resonant amplifier circuit.

10. An aerosol generating device, characterized in that, include: A containment cavity for holding aerosol-generating products; Second coil; A PCB board is provided with a circuit, the circuit including a detection circuit, a heating circuit, and a first switch. One end of the first switch is connected to the second coil, and the other end of the first switch is connected to either the detection circuit or the heating circuit. The detection circuit includes: The second resonant amplifier circuit is used to determine the electromagnetic signal of the second coil. The second resonant amplifier circuit includes a second inductor, a second resistor, and a second capacitor. The second inductor and the second resistor are derived from the connected second coil. The electromagnetic signal is used to determine whether the object to be tested placed in the receiving cavity is a foreign object, so that the aerosol generating device is in a heated or unheated state.

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