A heated smoking device

Abstract

The present application is applicable to the technical field of heated smoking articles, and provides a heated smoking article, including: a battery, a radio frequency circuit, a resonant cavity, a shielding cover and a shell, wherein the battery, the radio frequency circuit, the resonant cavity and the shielding cover are arranged inside the shell; the battery is electrically connected to the radio frequency circuit, and is used to power the radio frequency circuit; the radio frequency circuit is used to generate a radio frequency signal; the resonant cavity is connected to the radio frequency circuit, and is used to convert the radio frequency signal generated by the radio frequency circuit into heat energy to heat the cigarette cartridge; the shielding cover is arranged outside the radio frequency circuit, and an opening is provided at the top of the shielding cover, and the opening is used to connect the resonant cavity to the radio frequency circuit. The heated smoking article adopts a power oscillator to generate a high-efficiency and high-power microwave signal, and the microwave is converted into heat energy in the resonant cavity to heat the cigarette cartridge, which has the advantages of rapid and uniform heating and strong penetration, effectively improves the carbonization rate of the cigarette cartridge, and the heated cigarette cartridge has a good taste and a high utilization rate of the cigarette cartridge.

Description

Technical Field

[0001] The present application belongs to the technical field of heated smoking articles, and in particular, relates to a heated smoking article. Background Art

[0002] Heat-not-burn tobacco uses a low-temperature heating method, which not only retains the smoking experience of traditional tobacco, but also reduces the content of harmful substances such as tar and nicotine produced by high temperatures. At the same time, it does not produce ash and open flames, and is well received by consumers and businesses.

[0003] Heat-not-burn tobacco products mainly include resistance heating type and electromagnetic heating type. Resistance heating type heats the tobacco cartridge by contacting the resistance wire, and heats the tobacco cartridge by heat conduction and convection. It has the disadvantages of long preheating time, poor heating penetration and uniformity, low utilization rate of tobacco cartridge, easy burning and poor taste of tobacco cartridge, etc. Electromagnetic heating type heats the tobacco cartridge by contacting the electromagnetic heating metal rod. In addition to the above disadvantages, it also has the problems of low electromagnetic to heat conversion efficiency and low heating efficiency. Summary of the invention

[0004] In view of this, the embodiment of the present application provides a heated smoking device, which has the advantages of rapid and uniform heating and strong penetration, effectively improves the carbonization rate of the cigarette cartridge, and the heated cigarette cartridge has a good taste and a high utilization rate of the cigarette cartridge.

[0005] This application is implemented through the following technical solutions:

[0006] In the first aspect, an embodiment of the present application provides a heating smoking device, comprising: a battery, a radio frequency circuit, a resonant cavity, a shielding cover and a shell, wherein the battery, the radio frequency circuit, the resonant cavity and the shielding cover are arranged inside the shell; the battery is electrically connected to the radio frequency circuit for powering the radio frequency circuit; the radio frequency circuit is used to generate a radio frequency signal; the resonant cavity is connected to the radio frequency circuit for converting the radio frequency signal generated by the radio frequency circuit into thermal energy to heat the smoking cartridge; the shielding cover is arranged outside the radio frequency circuit and the shielding cover, and an opening is provided on the top of the shielding cover, and the opening is used to connect the resonant cavity to the radio frequency circuit.

[0007] In the embodiment of the present application, the above-mentioned heating tobacco device adopts a power oscillator to generate a high-efficiency and high-power microwave signal, and converts the microwave into thermal energy in the resonant cavity to achieve heating of the tobacco cartridge, which has the advantages of rapid, uniform heating and strong penetration, effectively improves the carbonization rate of the tobacco cartridge, and the heated tobacco cartridge has a good taste and a high utilization rate of the tobacco cartridge.

[0008] Based on the first aspect, in some embodiments, the RF circuit includes a power supply unit, a starting unit and a RF unit; the power supply unit is connected to the starting unit, and the starting unit is connected to the RF unit; the power supply unit is used to supply power to the RF unit, the starting unit is used to control the starting of the RF unit, and the RF unit is used to generate a RF signal through power oscillation.

[0009] Based on the first aspect, in some embodiments, the radio frequency unit includes a GaN die, a tuning circuit, a feedback circuit, a load matching circuit, a gate bias circuit and a drain bias circuit; the tuning circuit and the gate bias circuit are connected to the feedback circuit, one end of the feedback circuit is connected to the gate of the GaN die, and the other end is connected to the drain of the GaN die; one end of the load matching circuit is connected to the drain of the GaN die, and the other end is connected to the drain bias circuit; the GaN die is used to amplify the signal, the gate bias circuit is used to provide a gate voltage for the GaN die, the drain bias circuit is used to provide a drain voltage for the GaN die, the tuning circuit is used for frequency tuning, the feedback circuit is used to select the oscillation frequency and form a positive feedback loop, and the load matching circuit is used to achieve harmonic matching at the output end.

[0010] Based on the first aspect, in some embodiments, the tuning circuit includes a first capacitor, a second capacitor, a third capacitor, a first varactor, a first microstrip line and a first inductor; the first end of the first capacitor is connected to the first end of the first microstrip line, the second end of the first capacitor is grounded, the second end of the first microstrip line is connected to the first end of the second capacitor, the second end of the second capacitor is grounded, the first end of the third capacitor is connected to the first end of the second capacitor, the second end of the third capacitor is connected to a common node between the first end of the first inductor and the first end of the first varactor, the second end of the first inductor is connected to the frequency modulation voltage, and the second end of the first varactor is grounded.

[0011] Based on the first aspect, in some embodiments, the gate bias circuit includes a fourth capacitor, a fifth capacitor, a second microstrip line and a first resistor; the first end of the fifth capacitor is connected to the gate voltage, the second end of the fifth capacitor is grounded, the first end of the first resistor is connected to the gate voltage, the second end of the first resistor is connected to a common node between the first end of the fourth capacitor and the first end of the second microstrip line, the second end of the fourth capacitor is grounded, and the second end of the second microstrip line is connected to the second end of the first microstrip line.

[0012] Based on the first aspect, in some embodiments, the feedback circuit includes a third microstrip line, a fourth microstrip line, a fifth microstrip line and a sixth capacitor; a common node between a first end of the fifth microstrip line and a first end of the third microstrip line is connected to a first end of the third capacitor, a second end of the fifth microstrip line is connected to a gate of the GaN die, a second end of the third microstrip line is connected to a first end of the sixth capacitor, a second end of the sixth capacitor is connected to a first end of the fourth microstrip line, and a second end of the fourth microstrip line is connected to a drain of the GaN die.

[0013] Based on the first aspect, in some embodiments, the load matching circuit includes a sixth microstrip line, a seventh microstrip line, an eighth microstrip line, a ninth microstrip line, a tenth microstrip line, a seventh capacitor and a load resistor; the first end of the sixth microstrip line is connected to the drain of the GaN core, the second end of the sixth microstrip line is connected to the common node of the first end of the seventh microstrip line, the first end of the eighth microstrip line and the second end of the eleventh microstrip line, the second end of the eighth microstrip line is connected to the common node of the tenth microstrip line and the first end of the ninth microstrip line, the second end of the ninth microstrip line is connected to the seventh capacitor, the second end of the seventh capacitor is connected to the common node of the first end of the load resistor and the power output end, and the second end of the load resistor is grounded.

[0014] Based on the first aspect, in some embodiments, the drain bias circuit includes an eleventh microstrip line, a twelfth microstrip line, a thirteenth microstrip line, a fourteenth microstrip line and an eighth capacitor; the first end of the eleventh microstrip line is connected to a common node of the first end of the twelfth microstrip line, the first end of the thirteenth microstrip line and the second end of the fourteenth microstrip line, the second end of the eleventh microstrip line is connected to the second end of the sixth microstrip line, the first end of the fourteenth microstrip line is connected to the common node of the first end of the eighth capacitor and the drain voltage, and the second end of the eighth capacitor is grounded.

[0015] Based on the first aspect, in some embodiments, the startup unit includes a second resistor, a third resistor, a fourth resistor, a fifth resistor, a ninth capacitor, a tenth capacitor, a first diode, a second diode, a third diode, a fourth diode, a first field effect transistor, a second field effect transistor and a first switch; the source of the first field effect transistor is connected to the input voltage terminal, the drain of the first field effect transistor is connected to the output voltage terminal, the first end of the first resistor is connected to the source of the first field effect transistor, the second end of the first resistor is connected to the gate of the first field effect transistor, the first end of the second field effect transistor is connected to the gate of the first field effect transistor, the second end of the second field effect transistor is connected to the drain of the second field effect transistor, the positive electrode of the first diode is connected to the input signal terminal, and the negative electrode of the first diode is connected to the negative electrode of the first switch. The first end, the positive electrode of the second diode is connected to the drain of the second field effect tube, the negative electrode of the second diode is connected to the first end of the first switch, the second end of the first switch is connected to the source of the second field effect tube, the first capacitor is connected in parallel to the source and drain of the second field effect tube, the second capacitor is connected in parallel to the gate and source of the second field effect tube, the third resistor is connected in parallel to the second capacitor, the source of the second field effect tube is connected to the pull-up voltage, the first end of the fourth resistor is connected to the gate of the second field effect tube, the second end of the fourth resistor is connected to the output signal end, the positive electrode of the third diode is connected to the source of the first field effect tube, the negative electrode of the third diode is connected to the drain of the first field effect tube, the positive electrode of the fourth diode is connected to the source of the second field effect tube, and the negative electrode of the fourth diode is connected to the drain of the second field effect tube.

[0016] Based on the first aspect, in some embodiments, the RF circuit sets the impedance matching value of the RF circuit according to the resonant cavity oscillator, and the impedance matching between the RF circuit and the resonant cavity array is the best and most impedance matching.

[0017] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0019] Figure 1 is a schematic diagram of the structure of the heating smoking device provided in the embodiment of the present application;

[0020] Figure 2 It is a schematic diagram of the structure of the radio frequency circuit of the heating smoking device provided in the embodiment of the present application;

[0021] Figure 3 This is a schematic diagram of a radio frequency unit for a heated smoking device provided in an embodiment of the present application;

[0022] Figure 4 This is a schematic diagram of the heating smoking device starting unit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0023] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0024] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.

[0025] It should also be understood that the term “and / or” used in the specification and appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0026] As used in the specification and appended claims of this application, the term "if" can be interpreted as "when" or "uponce" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "uponce it is determined" or "in response to determining" or "uponce [described condition or event] is detected" or "in response to detecting [described condition or event]", depending on the context.

[0027] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0028] References to "one embodiment" or "some embodiments" etc. described in the specification of this application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0029] Based on the technical problems mentioned in the background technology, an embodiment of the present application provides a heating smoking device, which adopts a power oscillator to generate a high-efficiency and high-power microwave signal, and converts the microwave into thermal energy in the resonant cavity to heat the cigarette cartridge. It has the advantages of rapid, uniform heating and strong penetration, effectively improves the carbonization rate of the cigarette cartridge, and the heated cigarette cartridge has a good taste and a high utilization rate of the cigarette cartridge.

[0030] like Figure 1 As shown, a heating smoking device provided by an embodiment of the present application includes: a battery 1, a radio frequency circuit 2, a resonant cavity 3, a shielding cover 4 and a shell 5. The battery 1, the radio frequency circuit 2, the resonant cavity 3, and the shielding cover 4 are arranged inside the shell 5. The battery 1 is electrically connected to the radio frequency circuit 2 for powering the radio frequency circuit 2. The radio frequency circuit 2 is used to generate a radio frequency signal. The resonant cavity 3 is connected to the radio frequency circuit 2 for converting the radio frequency signal generated by the radio frequency circuit 2 into heat energy to heat the cigarette cartridge. The shielding cover 4 is arranged outside the radio frequency circuit 2, and an opening is provided at the top of the shielding cover 4, and the opening is used to connect the resonant cavity 3 to the radio frequency circuit 2.

[0031] In some embodiments, battery 1 is implemented by two lithium batteries connected in series, wherein the voltage range of a single battery is 3.7V to 4.2V, the overall voltage range of the series-connected batteries is 7.4V to 8.4V, and the battery internal resistance is required to be less than 100mΩ. Two specifications are developed and produced according to the battery capacity, one battery 1 has a capacity of 200mAh, and the other has a capacity of 1200mAh, which are respectively suitable for 3 and 20 cigarette cartridges, and can be charged and discharged for more than 300 times.

[0032] The RF circuit 2 is the core component of the heat-not-burn smoking device. It is a GaN HEMT parallel feedback common-source (CS) oscillator with harmonic tuning components, which is used to generate RF signals through power oscillation. Figure 2 As shown, the radio frequency circuit 2 includes a power supply unit 200, a start-up unit 210 and a radio frequency unit 220. The power supply unit 200 is connected to the start-up unit 210, and the start-up unit 210 is connected to the radio frequency unit 220. The start-up unit 210 is used to control the radio frequency unit 220 to start.

[0033] In some embodiments, the radio frequency circuit 2 further includes a single chip microcomputer, which has an ADC analog-to-digital conversion module that can convert analog signals into digital signals. The single chip microcomputer can sample the voltage of the battery 1 to determine whether the battery 1 is low on power. When the battery is low on power, the single chip microcomputer controls the three-color light on the housing 5 to display red, and when the battery is not low on power, it displays green.

[0034] In some embodiments, the power supply unit 200 is used to supply power to the radio frequency unit 220. The circuit of the power supply unit 200 also has a voltage stabilization function, realizing a voltage stabilization power supply of 7.4V to 8.4V for the battery 1. The power supply unit 200 can generate a 3.3V±0.05V voltage to provide to the above-mentioned single chip microcomputer and the three-color light circuit of the housing 5, etc., and generate a -1.2V±0.05V voltage to provide to the gate voltage VG of the gate bias circuit Y4 of the radio frequency unit 220.

[0035] Figure 3 The schematic diagram of the radio frequency unit 220 is shown in FIG. The radio frequency unit 220 includes a GaN die X1, a tuning circuit Y1, a feedback circuit Y2, a load matching circuit Y3, a gate bias circuit Y4, and a drain bias circuit Y5.

[0036] The tuning circuit Y1 and the gate bias circuit Y4 are connected to the feedback circuit Y2, one end of the feedback circuit Y2 is connected to the gate of the GaN die X1, and the other end is connected to the drain of the GaN die X1. One end of the load matching circuit Y3 is connected to the drain of the GaN die X1, and the other end is connected to the drain bias circuit Y5.

[0037] The GaN die X1 is used to amplify the signal, the gate bias circuit Y4 is used to provide the gate voltage for the GaN die X1, the drain bias circuit Y5 is used to provide the drain voltage VD for the GaN die X1, the tuning circuit Y1 is used for frequency tuning, the feedback circuit Y2 is used to select the frequency of the oscillation circuit and form a positive feedback loop, and the load matching circuit Y3 is used to achieve harmonic matching at the output end.

[0038] In some embodiments, the above-mentioned single chip microcomputer can generate a variable duty cycle PWM signal to control the drain voltage VD provided by the PMOS tube to the drain bias circuit Y5 of the RF unit 220. By adjusting the drain voltage VD, the output power of the RF unit 220 can be adjusted to achieve different heating times for different cigarette cartridges, thereby achieving rapid smoke discharge from the cigarette cartridge while avoiding burning of the cigarette cartridge.

[0039] The above-mentioned single chip microcomputer also has a DAC digital-to-analog conversion module, which generates a tuning voltage Vtune through the DAC digital-to-analog conversion module of the single chip microcomputer to control the variable capacitance diode in the tuning circuit Y1 to complete the frequency scanning function. The frequency scanning range is adjustable, for example, between 2.43GHz and 2.47GHz.

[0040] In some embodiments, the GaN die X1 is used to amplify the signal, the saturated power density of GaN is 3W / mm~4W / mm, the burnout voltage is greater than 100V, the material thermal resistance is about 2℃ / W, and the rated junction temperature is 175℃. The selection of the GaN die X1 parameters determines the technical indicators such as the maximum output power of the oscillator and the maximum gain of small signals. The output power of the S-band GaN power oscillator successfully developed so far ranges from a few watts to hundreds of watts, and the efficiency can reach more than 71%, which can be efficiently applied to the above-mentioned RF circuit 2.

[0041] In some embodiments, the tuning circuit Y1 is used for frequency tuning. The tuning circuit Y1 includes a first capacitor C1, a second capacitor C2, a third capacitor C3, a first varactor DIODE1, a first microstrip line TL1, and a first inductor. The first end of the first capacitor C1 is connected to the first end of the first microstrip line TL1, the second end of the first capacitor C1 is grounded, the second end of the first microstrip line TL1 is connected to the first end of the second capacitor C2, the second end of the second capacitor C2 is grounded, the first end of the third capacitor C3 is connected to the first end of the second capacitor C2, the second end of the third capacitor C3 is connected to the common node of the first end of the first inductor and the first end of the first varactor DIODE1, the second end of the first inductor is connected to the frequency modulation voltage Vtune, and the second end of the first varactor DIODE1 is grounded.

[0042] The second capacitor C2 meets the large signal working amplitude and phase conditions of the oscillator, and is connected in parallel with the third capacitor C3, the first inductor L1 and the first variable capacitance diode DIODE1 to form a tuning capacitor for frequency tuning. The first microstrip line TL1 is equivalent to an inductor, which is connected in series with the first capacitor C1 and connected to the gate of the GaN core through the fifth microstrip line TL5 to form a short-circuit matching of the second harmonic input end, which can effectively improve the efficiency of the oscillator. The tuning circuit Y1 is connected to the gate of the GaN core X1 and plays a role similar to a self-bias voltage. It can adaptively adjust the gate voltage of the GaN core to stabilize the gate current and ensure that the core is in a safe working state. At the same time, the tuning circuit Y1Y1 also achieves fast oscillation, and its oscillation time is less than 10ns.

[0043] In some embodiments, the gate bias circuit Y4 includes a fourth capacitor C4, a fifth capacitor C5, a second microstrip line TL2 and a first resistor R1.

[0044] The first end of the fifth capacitor C5 is connected to the gate voltage VG, the second end of the fifth capacitor C5 is grounded, the first end of the first resistor R1 is connected to the gate voltage VG, the second end of the first resistor R1 is connected to the common node of the first end of the fourth capacitor C4 and the first end of the second microstrip line TL2, the second end of the fourth capacitor C4 is grounded, and the second end of the second microstrip line TL2 is connected to the second end of the first microstrip line TL1. The gate bias circuit Y4 is used to provide a gate voltage VG for the GaN die X1. According to the design function of the RF circuit 2, the gate voltage VG is -1.2V.

[0045] In some embodiments, the feedback circuit Y2 is used to select the oscillation frequency and form a positive feedback loop. The feedback circuit Y2 includes a third microstrip line TL3, a fourth microstrip line TL4, a fifth microstrip line TL5 and a sixth capacitor C6.

[0046] The common node of the first end of the fifth microstrip line TL5 and the first end of the third microstrip line TL3 is connected to the first end of the third capacitor C3, the second end of the fifth microstrip line TL5 is connected to the gate of the GaN die X1, the second end of the third microstrip line TL3 is connected to the first end of the sixth capacitor C6, the second end of the sixth capacitor C6 is connected to the first end of the fourth microstrip line TL4, and the second end of the fourth microstrip line TL4 is connected to the drain of the GaN die X1. The third microstrip line TL3, the fourth microstrip line TL4 and the fifth microstrip line TL5 are equivalent to inductors L, and the open-loop oscillation frequency point is calculated by the equivalent inductors and the sixth capacitor C6, and the switch oscillation frequency is designed to be the center frequency of the required frequency band to achieve oscillation frequency selection. Select the appropriate capacitance value of the sixth capacitor C6 and the inductor L value, and determine the width and length of the third microstrip line TL3, the fourth microstrip line TL4 and the fifth microstrip line TL5 by calculation or simulation.

[0047] In some embodiments, the load matching circuit Y3 is used to achieve output end harmonic matching. The load matching circuit Y3 includes a sixth microstrip line TL6, a seventh microstrip line TL7, an eighth microstrip line TL8, a ninth microstrip line TL9, a tenth microstrip line TL10, a seventh capacitor C7 and a load resistor RL.

[0048] The first end of the sixth microstrip line TL6 is connected to the drain of the GaN die X1, the second end of the sixth microstrip line TL6 is connected to the common node of the first end of the seventh microstrip line TL7, the first end of the eighth microstrip line TL8 and the second end of the eleventh microstrip line TL11, the second end of the eighth microstrip line TL8 is connected to the common node of the first end of the tenth microstrip line TL10 and the ninth microstrip line TL9, the second end of the ninth microstrip line TL9 is connected to the seventh capacitor C7, the second end of the seventh capacitor C7 is connected to the first end of the load resistor RL and the common node of the power output terminal Pout, and the second end of the load resistor RL is grounded. The seventh capacitor C7 is a DC blocking capacitor. The sixth microstrip line TL6, the seventh microstrip line TL7, the eighth microstrip line TL8, the ninth microstrip line TL9 and the tenth microstrip line TL10 are used for harmonic matching to achieve output end harmonic matching and improve output efficiency.

[0049] In some embodiments, the drain bias circuit Y5 is used to provide a drain voltage VD for the GaN die X1, and the RF unit 220 adopts a similar self-biased gate voltage design, and the drain voltage can be designed according to the voltage of the system battery 1. The drain bias circuit Y5 includes an eleventh microstrip line TL11, a twelfth microstrip line TL12, a thirteenth microstrip line TL13, a fourteenth microstrip line TL14 and an eighth capacitor C8.

[0050] The first end of the eleventh microstrip line TL11 is connected to a common node of the first end of the twelfth microstrip line TL12, the first end of the thirteenth microstrip line TL13 and the second end of the fourteenth microstrip line TL14, the second end of the eleventh microstrip line TL11 is connected to the second end of the sixth microstrip line TL6, the first end of the fourteenth microstrip line TL14 is connected to a common node of the first end of the eighth capacitor C8 and the drain voltage VD, and the second end of the eighth capacitor C8 is grounded.

[0051] like Figure 4 As shown, the startup unit 210 includes a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a ninth capacitor C9, a tenth capacitor C10, a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a first field effect transistor Q1, a second field effect transistor Q2 and a first switch S1.

[0052] The source of the first field effect transistor Q1 is connected to the input voltage terminal, the drain of the first field effect transistor Q1 is connected to the output voltage terminal, the first end of the first resistor R1 is connected to the source of the first field effect transistor Q1, the second end of the first resistor R1 is connected to the gate of the first field effect transistor Q1, the first end of the second field effect transistor Q2 is connected to the gate of the first field effect transistor Q1, the second end of the second field effect transistor Q2 is connected to the drain of the second field effect transistor Q2, the anode of the first diode D1 is connected to the input signal terminal, the cathode of the first diode D1 is connected to the first end of the first switch S1, the anode of the second diode D2 is connected to the drain of the second field effect transistor Q2, the cathode of the second diode D2 is connected to the first end of the first switch S1, and the cathode of the first switch S1 is connected to the gate of the first field effect transistor Q1. The second end is connected to the source of the second field effect transistor Q2, the first capacitor C1 is connected in parallel to both sides of the source and drain of the second field effect transistor Q2, the second capacitor C2 is connected in parallel to both sides of the gate and source of the second field effect transistor Q2, the third resistor R3 is connected in parallel to the second capacitor C2, the source of the second field effect transistor Q2 is connected to the pull-up voltage, the first end of the fourth resistor R4 is connected to the gate of the second field effect transistor Q2, the second end of the fourth resistor R4 is connected to the output signal end, the positive electrode of the third diode D3 is connected to the source of the first field effect transistor Q1, the negative electrode of the third diode D3 is connected to the drain of the first field effect transistor Q1, the positive electrode of the fourth diode D4 is connected to the source of the second field effect transistor Q2, and the negative electrode of the fourth diode D4 is connected to the drain of the second field effect transistor Q2. The eighth capacitor C8 is a bypass capacitor.

[0053] In the shutdown state, long press the first switch S1, at this time the first field effect tube Q1 is turned on, Vout is powered on, and the MCU works normally. After a certain delay, the MCU_IO port changes to the input pull-up state. When S1 is disconnected, Q2 is turned on, which can maintain Q1 on and Vout is powered normally, thus realizing long press to start.

[0054] In the power-on state, long press switch S1 to detect that MCU_IO is at a low level. After a delay, detect MCU_IO as a low level again, set the MCU_IO port to input low level, and the second field effect tube Q2 is cut off. When the button is released, the first field effect tube Q1 is cut off, and Vout is disconnected, so as to achieve long press shutdown. At this time, the RF component is completely turned off, and the static current is only the current consumed by battery 1. The theoretical standby current is less than 0.1uA, and it can be in standby for a long time. You can also use the counter to count for 2 and a half minutes in the power-on state. After the heating of the cigarette cartridge is completed, set the MCU_IO port to input low level and automatically shut down.

[0055] The RF circuit 2 can quickly oscillate and output a 7.6W continuous wave RF signal within 10ns, with a high output efficiency of more than 71%, and can quickly start oscillation in 8ns. The steady-state temperature is about 65°C when installed on a metal base. It also has a frequency sweep function within the range of 2.43GHz to 2.47GHz.

[0056] In some embodiments, the resonant cavity 3 of the above-mentioned heated tobacco device is connected to the RF circuit 2, which is used to convert the RF signal generated by the RF circuit 2 into heat energy to heat the tobacco cartridge, so as to achieve efficient conversion of RF energy. The power oscillator and the resonant cavity 3 are jointly designed, and the RF circuit 2 sets the impedance matching value of the RF circuit 2 according to the oscillator of the resonant cavity 3. The impedance matching of the RF circuit 2 and the resonant cavity 3 is the best and most anti-matching. Different from the conventional 50Ω output impedance selection, the above-mentioned tobacco device is directly matched to the optimal impedance of the resonant cavity 3 and the RF circuit 2, and no longer converted to 50Ω.

[0057] In some embodiments, the shielding cover 4 is mainly used for radio frequency signal shielding to prevent personal injury caused by signal radiation. After the design of the resonant cavity 3 and the shielding cover 4, the test radiation intensity outside the smoking device is far less than the national standard requirement of 0.4 watts per square meter, achieving the purpose of green and environmentally friendly application. At the same time, it has passed the electromagnetic compatibility test to avoid the possibility of affecting the normal operation of other electronic devices such as mobile phones and computers when the heating smoking device is working.

[0058] In some embodiments, the housing 5 of the heating smoking device is used to install the battery 1, the RF circuit 2, the resonant cavity 3 and the shielding cover 4. The RF components can be isolated from direct contact with the human body to prevent the temperature of the RF components from being transferred to the human body.

[0059] The above-mentioned heating smoking device is the first to adopt a power oscillator as a radio frequency source, which improves the power added efficiency and increases the smoking time of the cigarette cartridge. The heating smoking device using this radio frequency circuit 2 can generate high-power and high-efficiency radio frequency signals in a single stage, greatly reducing the size of the heating smoking device and the cost, which is conducive to industrial mass production.

[0060] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0061] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0062] In the embodiments provided in the present application, it should be understood that the disclosed devices / network equipment and methods can be implemented in other ways. For example, the device / network equipment embodiments described above are merely schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0063] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0064] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A heated smoking device, characterized in that: include: A battery, a radio frequency circuit, a resonant cavity, a shielding cover and a shell, wherein the battery, the radio frequency circuit, the resonant cavity and the shielding cover are arranged inside the shell; The battery is electrically connected to the radio frequency circuit and is used to supply power to the radio frequency circuit; The radio frequency circuit is used to generate a radio frequency signal; The resonant cavity is connected to the radio frequency circuit and is used to convert the radio frequency signal generated by the radio frequency circuit into thermal energy to heat the cigarette cartridge; The shielding cover is arranged outside the radio frequency circuit and the shielding cover, and an opening is arranged on the top of the shielding cover, and the opening is used to connect the resonant cavity with the radio frequency circuit; The radio frequency circuit includes a power supply unit, a start-up unit and a radio frequency unit; The power supply unit is connected to the start-up unit, and the start-up unit is connected to the radio frequency unit; The power supply unit is used to supply power to the radio frequency unit, the start-up unit is used to control the start-up of the radio frequency unit, and the radio frequency unit is used to generate a radio frequency signal through power oscillation; The radio frequency unit includes a GaN die, a tuning circuit, a feedback circuit, a load matching circuit, a gate bias circuit and a drain bias circuit; The tuning circuit and the gate bias circuit are connected to the feedback circuit, one end of the feedback circuit is connected to the gate of the GaN die, and the other end is connected to the drain of the GaN die; One end of the load matching circuit is connected to the drain of the GaN die, and the other end is connected to the drain bias circuit; The GaN die is used to amplify signals, the gate bias circuit is used to provide a gate voltage for the GaN die, the drain bias circuit is used to provide a drain voltage for the GaN die, the tuning circuit is used for frequency tuning, the feedback circuit is used to select an oscillation frequency and form a positive feedback loop, and the load matching circuit is used to achieve harmonic matching at the output end.

2. The heating smoking device according to claim 1, characterized in that: The tuning circuit includes a first capacitor, a second capacitor, a third capacitor, a first varactor diode, a first microstrip line and a first inductor; The first end of the first capacitor is connected to the first end of the first microstrip line, the second end of the first capacitor is grounded, the second end of the first microstrip line is connected to the first end of the second capacitor, the second end of the second capacitor is grounded, the first end of the third capacitor is connected to the first end of the second capacitor, the second end of the third capacitor is connected to a common node between the first end of the first inductor and the first end of the first varactor, the second end of the first inductor is connected to a frequency modulation voltage, and the second end of the first varactor is grounded.

3. The heating smoking device according to claim 2, characterized in that: The gate bias circuit includes a fourth capacitor, a fifth capacitor, a second microstrip line and a first resistor; The first end of the fifth capacitor is connected to the gate voltage, the second end of the fifth capacitor is grounded, the first end of the first resistor is connected to the gate voltage, the second end of the first resistor is connected to a common node between the first end of the fourth capacitor and the first end of the second microstrip line, the second end of the fourth capacitor is grounded, and the second end of the second microstrip line is connected to the second end of the first microstrip line.

4. The heating smoking device according to claim 3, characterized in that: The feedback circuit includes a third microstrip line, a fourth microstrip line, a fifth microstrip line and a sixth capacitor; A common node between the first end of the fifth microstrip line and the first end of the third microstrip line is connected to the first end of the third capacitor, the second end of the fifth microstrip line is connected to the gate of the GaN die, the second end of the third microstrip line is connected to the first end of the sixth capacitor, the second end of the sixth capacitor is connected to the first end of the fourth microstrip line, and the second end of the fourth microstrip line is connected to the drain of the GaN die.

5. The heating smoking device according to claim 4, characterized in that: The load matching circuit includes a sixth microstrip line, a seventh microstrip line, an eighth microstrip line, a ninth microstrip line, a tenth microstrip line, a seventh capacitor and a load resistor; The first end of the sixth microstrip line is connected to the drain of the GaN core, the second end of the sixth microstrip line is connected to a common node of the first end of the seventh microstrip line, the first end of the eighth microstrip line and the second end of the eleventh microstrip line, the second end of the eighth microstrip line is connected to a common node of the tenth microstrip line and the first end of the ninth microstrip line, the second end of the ninth microstrip line is connected to the seventh capacitor, the second end of the seventh capacitor is connected to a common node of the first end of the load resistor and the power output end, and the second end of the load resistor is grounded.

6. The heating smoking device according to claim 5, characterized in that: The drain bias circuit includes an eleventh microstrip line, a twelfth microstrip line, a thirteenth microstrip line, a fourteenth microstrip line and an eighth capacitor; The first end of the eleventh microstrip line is connected to a common node of the first end of the twelfth microstrip line, the first end of the thirteenth microstrip line and the second end of the fourteenth microstrip line, the second end of the eleventh microstrip line is connected to the second end of the sixth microstrip line, the first end of the fourteenth microstrip line is connected to the first end of the eighth capacitor and the common node of the drain voltage, and the second end of the eighth capacitor is grounded.

7. The heated smoking article according to claim 1, characterized in that: The startup unit includes a second resistor, a third resistor, a fourth resistor, a fifth resistor, a ninth capacitor, a tenth capacitor, a first diode, a second diode, a third diode, a fourth diode, a first field effect transistor, a second field effect transistor and a first switch; The source of the first field effect transistor is connected to the input voltage terminal, the drain of the first field effect transistor is connected to the output voltage terminal, the first end of the first resistor is connected to the source of the first field effect transistor, the second end of the first resistor is connected to the gate of the first field effect transistor, the first end of the second field effect transistor is connected to the gate of the first field effect transistor, the second end of the second field effect transistor is connected to the drain of the second field effect transistor, the anode of the first diode is connected to the input signal terminal, the cathode of the first diode is connected to the first end of the first switch, the anode of the second diode is connected to the drain of the second field effect transistor, the cathode of the second diode is connected to the first end of the first switch, and the cathode of the first switch is connected to the gate of the first field effect transistor. The second end is connected to the source of the second field effect tube, the first capacitor is connected in parallel to both sides of the source and drain of the second field effect tube, the second capacitor is connected in parallel to both sides of the gate and source of the second field effect tube, the third resistor is connected in parallel to the second capacitor, the source of the second field effect tube is connected to the pull-up voltage, the first end of the fourth resistor is connected to the gate of the second field effect tube, the second end of the fourth resistor is connected to the output signal end, the anode of the third diode is connected to the source of the first field effect tube, the cathode of the third diode is connected to the drain of the first field effect tube, the anode of the fourth diode is connected to the source of the second field effect tube, and the cathode of the fourth diode is connected to the drain of the second field effect tube.

8. The heated smoking article according to claim 1, characterized in that: The radio frequency circuit sets the radio frequency circuit impedance matching value according to the resonant cavity oscillator, and the impedance matching between the radio frequency circuit and the resonant cavity array is the best and most impedance matching.

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