A heating non-combustion electronic cigarette using a radio frequency microwave source

Abstract

The application provides a heating non-combustion electronic cigarette with a radio frequency microwave source, and belongs to the technical field of electronic cigarettes.The electronic cigarette comprises a cartridge, a smoke cavity, a radio frequency microwave source and a shell; the smoke cavity is a metal cavity, a slit line is etched on the metal surface of the smoke cavity, the slit line is connected at the head and tail or meanders to form a slit grid, the radio frequency microwave source is connected with the metal surface of the smoke cavity through a feed line, and the shell is arranged outside the smoke cavity.The metal wall of the smoke cavity is used as a microwave coupling structure and an electromagnetic shielding boundary at the same time, the slit grid is used as a magnetic current radiation source to uniformly couple microwave energy to the inside of the smoke cavity, and an independent conductor or a dielectric skeleton does not need to be additionally arranged.The application has the advantages of uniform heating and high energy efficiency, can realize synchronous heating in a small size smoke cavity, and overcomes the problems of local overheating or insufficient heating caused by uneven field distribution in the prior art.

Description

Technical Field

[0001] This invention relates to the field of electronic cigarette technology, and more specifically to a heated non-combustible electronic cigarette using a radio frequency microwave source. Background Technology

[0002] Heated tobacco products (HTPs) are consumer electronic devices that provide a continuous energy supply to the cartridges, causing them to heat up and produce smoke at approximately 300°C. As handheld devices, the size of the device is close to or smaller than the human palm, and the surface temperature should not be too high to avoid discomfort when holding it. The cartridge filling material is usually prepared in powder, flocculent, flake, or aerosol form, and the cartridge is rod-shaped or cylindrical, allowing it to be fully or partially inserted into the e-cigarette's smoke chamber. The smoke chamber must have an opening that matches the size of the cartridge for insertion and removal.

[0003] The main technical problems with existing heated tobacco products are as follows: The first heating method uses DC / AC power as the heat source, heating through heat conduction. Specifically, the DC / AC power supply is connected to a resistive element, which is inserted into the cartridge and comes into contact with the cartridge filling. When current flows through the resistive element, electrical energy is converted into heat energy, which is then conducted to the cartridge filling through contact. However, the resistive element undergoes mechanical deformation due to force during cartridge insertion and removal, leading to non-homogeneous heat conduction. Furthermore, the amount of heat conducted from the resistive element to different parts of the cartridge depends on the orientation and distance of the corresponding part of the cartridge relative to the resistive element, inevitably resulting in non-uniform and asynchronous heating. Even if the resistive element is configured as a coil structure surrounding the cartridge, with heat transferred from the periphery to the center, it still leads to localized overheating and non-uniform heating of the cartridge filling.

[0004] The second heating method uses an alternating electromagnetic field to generate eddy currents in a sensor for heating. Specifically, an alternating magnetic field is applied to a ferromagnetic sensor via a coil, with the cartridge positioned entirely or partially around the sensor, thereby heating the sensor and the surrounding cartridge. However, due to the varying orientation and distance of the cartridge relative to the sensor, uniform or synchronous heating is also impossible. Non-uniform and asynchronous heating can alter the amount of smoke and flavor of the cartridge; some parts of the cartridge may be overheated, potentially generating or releasing unwanted substances, while other parts may not be sufficiently heated, resulting in the cartridge failing to generate enough smoke and leading to waste.

[0005] The third heating method uses microwaves as a heat source. Its principle is based on the polarization, movement, and friction of the cartridge molecules caused by microwaves, converting microwave energy into heat energy through mechanical motion. However, the microwave energy cavity-based electronic cigarette disclosed in patent document CN117582038A requires continuously bent metal strips wound on a non-metallic support structure. Microwave energy is introduced by adjusting the length, width, and spacing of the metal strips to construct an equivalent LRC circuit. However, in this solution, the metal strips, as solid conductors, primarily confine energy to the vicinity of the conductor or the gaps between adjacent strips, making it difficult to form a circumferentially balanced field distribution across the cavity cross-section, resulting in inconsistent heating of different parts of the cartridge. Similarly, the microwave device for heating a multi-feed point columnar electronic cigarette disclosed in patent document CN116158565A uses two independent longitudinal metal sheets bent into a cylindrical shape around the shell axis as a radiation structure. It relies on a multi-layer dielectric substrate for positioning and isolation, making the manufacturing process complex. Furthermore, its energy confinement area is mainly limited to between the two metal sheets, making it difficult to ensure synchronous heating of different parts of the cartridge circumferentially. In addition, due to the miniaturization of heated non-combustible electronic cigarette devices, the resonant frequency of conventional cylindrical cavities is much higher than that of commonly used ISM low-frequency microwaves, making it difficult for microwave energy to effectively enter the cavity and form energy accumulation. Even if microwaves do enter the smoke cavity, they suffer from high radiation loss and low energy efficiency due to insufficient shielding.

[0006] In addition, precise detection and control of the temperature of the e-cigarette cartridge is a key factor in improving heating efficiency and user experience.

[0007] Therefore, there is an urgent need to provide a new microwave coupling structure that can achieve efficient feeding and uniform synchronous heating of microwave energy in a small-sized smoke cavity without the need to add internal independent conductors and multilayer dielectric substrates, and to overcome the shortcomings of the above-mentioned existing technologies with precise temperature control methods. Summary of the Invention

[0008] To address the problem of uneven field distribution leading to localized overheating or insufficient heating of the cartridge in existing microwave-heated electronic cigarettes, this invention provides a heated non-combustible electronic cigarette using a radio frequency microwave source. The metal wall of the cigarette chamber is etched with a slit grid to create a uniform volumetric energy distribution field within the chamber, thereby achieving synchronous and uniform heating of the cartridge.

[0009] To achieve the above objectives, the present invention provides a heated, non-combustible electronic cigarette using a radio frequency microwave source, comprising: Smoke cartridges; The smoke chamber is a metal cavity with one end open, used to accommodate the smoke cartridge. The metal surface of the smoke chamber is etched with slot lines, which are connected end to end or meander to form a slot grid. A radio frequency microwave source, wherein the radio frequency microwave source is connected to the metal surface of the smoke cavity via a feed line; A housing, which is fitted over the outside of the smoke chamber and has a gap space between it and the smoke chamber; The slotted grid is used to couple the microwave energy generated by the radio frequency microwave source into the interior of the smoke chamber to heat the smoke cartridge.

[0010] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention employs an integrated etched slotted grid mesh on the metal wall of the smoke chamber, allowing the metal wall to simultaneously serve as a microwave coupling structure and an electromagnetic shielding boundary, eliminating the need for any independent metal strips, metal radiating sheets, or dielectric support frameworks inside the smoke chamber. By removing material from the surface of a complete conductor to form the slotted grid mesh, each slot acts as an independent radiating unit, creating a balanced distribution of radiation phase and amplitude with near-uniformity in the circumferential direction of the smoke chamber. This achieves a uniform volumetric field distribution within ±25% of the energy density deviation and electric field phase delay deviation within the smoke chamber, which has an electrical dimension much smaller than the operating wavelength. This ensures that the molecular frictional heating of the various parts of the cartridge filling is essentially synchronized, and the internal temperature difference of the cartridge does not exceed 30°C. Attached Figure Description

[0011] The disclosure of this invention is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. In the drawings, the same reference numerals are used to refer to the same parts. Wherein: Figure 1 This is a functional module block diagram of a heated non-combustible electronic cigarette using a radio frequency microwave source according to the present invention; Figure 2 This is a schematic diagram of the smoke chamber structure of a heated non-combustible electronic cigarette using a radio frequency microwave source according to the present invention; Figure 3 This is a schematic diagram of the top surface of the smoke chamber in the first embodiment of the present invention; Figure 4 This is a schematic diagram of the bottom surface of the smoke chamber in the first embodiment of the present invention; Figure 5 This is a schematic diagram of the planar unfolded structure of the metal surface of the smoke chamber in the first embodiment of the present invention; Figure 6 This is a schematic diagram of the smoke chamber structure in the second embodiment of the present invention; Figure 7 This is a schematic diagram of the top surface of the smoke chamber in the second embodiment of the present invention; Figure 8 This is a schematic diagram of the bottom surface of the smoke chamber in the second embodiment of the present invention; Figure 9 This is a schematic diagram of the planar unfolded structure of the metal surface of the smoke chamber in the second embodiment of the present invention; Figure 10 These are schematic diagrams illustrating the usage state of the tobacco cartridge inserted into the tobacco chamber in the first and second embodiments of the present invention. In the picture: 1-Cartridge, 2-Main board, 3-Temperature sensor, 4-Control chip, 5-RF microwave source, 6-Battery, 7-Battery compartment; 11-Cartridge cavity, 12-Gap grid, 13-Cylindrical cavity, 14-Shell, 15-Circular opening, 16-Top surface, 17-Bottom surface, 18-Inner conductor, 181-Metal wire; 19-Through hole; 20-Outer conductor, 21-Corrugated structure, 22-Fixing groove, 23-Gap space, 24-Support structure; 31-Mouthpiece, 32-Cartridge filling. Detailed Implementation

[0012] It is readily understood that, based on the technical solution of this invention, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the invention. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solution of this invention and should not be considered as the entirety of the invention or as limitations or restrictions on the technical solution of this invention.

[0013] The present invention will be further described in detail below with reference to the accompanying drawings, but this is not intended to limit the scope of the invention.

[0014] like Figure 1 As shown, the present invention provides a heated non-combustible electronic cigarette using an radio frequency microwave source, which has a cylindrical or flat handheld structure and includes a cartridge 1, a smoke chamber 11, an radio frequency microwave source 5, a shell 14, a feed line, and a power management module.

[0015] Specifically, the cartridge 1 is a replaceable consumable, filled with powdered, flocculent, or sheet-like tobacco material or an aerosol generating matrix (i.e., cartridge filler 32). One end of the cartridge 1 has a mouthpiece 31, and the other end is an opening or a microwave-transparent end cap. The cartridge 1 can be heated by radio frequency microwaves without burning, causing the filler to release smoke after being heated, which is then inhaled by the user through the mouthpiece 31.

[0016] like Figure 2 As shown, the smoke chamber 11 is a hollow structure with one open end. Its internal shape is adapted to the shape of the smoke cartridge, preferably a cylindrical cavity 13, with the open end for inserting the smoke cartridge 1. The surface of the smoke chamber 11 is made of metal and has etched slot lines to form a slot grid 12. The slot grid 12 serves as a radiating antenna structure for radio frequency microwaves, used to couple the fed electromagnetic energy into the interior of the smoke chamber 11.

[0017] The housing 14 is fitted outside the smoke chamber 11, with a gap space 23 between it and the smoke chamber 11. This gap space 23 can be filled with air, or with a solid or liquid medium (such as ceramic, polytetrafluoroethylene, etc.) to adjust electromagnetic parameters or provide thermal insulation. The housing 14 is made of a metal surface, a mesh metal surface, or a magnetic medium with electromagnetic shielding function.

[0018] Furthermore, such as Figure 3 and Figure 4 As shown, the top surface 16 of the housing 14 has a circular opening 15, through which the smoke cartridge passes and is inserted into the cavity 13 of the smoke chamber 11. A corrugated structure 21 is etched on the opening surface of the circular opening 15. At microwave frequencies, the corrugated structure 21 is equivalent to a parallel inductor-capacitor resonant circuit, exhibiting high impedance characteristics at the opening, thereby effectively suppressing microwave radiation outward along the opening surface. This can control the radiation leakage power to below 5% of the total input power, improving energy utilization and ensuring user safety. The bottom surface 17 of the housing 14 has a through hole 19, and the housing 14 also has a fixing groove 22. The smoke chamber 11 can be screwed into the fixing groove 22 for easy disassembly and cleaning after use.

[0019] The radio frequency microwave source 5 is mounted on the main board 2 inside the housing 14, and its output is connected to the metal surface of the smoke chamber 11 and the slot grid 12 via a feed line. The feed line can be either a coaxial line or a parallel double-line structure. When the feed line is a coaxial line, the inner conductor 18 passes through the via 19 and is electrically connected to the metal surface of the smoke chamber 11, while the outer conductor 20 is electrically connected to the housing 14. When the feed line is a parallel double-line structure, both metal wires 181 pass through the via 19 and are electrically connected to different points on the metal surface of the smoke chamber 11. Both feed line methods can effectively transmit the microwave energy generated by the radio frequency microwave source 5 to the slot grid 12.

[0020] It should be noted that, unlike existing microwave-heated electronic cigarettes that use internal additional conductor structures (e.g., bent metal strips wound on a non-metallic support frame or independent multi-layered metal radiating sheets), this invention uses the metal wall of the smoke chamber itself as both a microwave coupling structure and an electromagnetic shielding boundary. The integrated etched slit grid on the smoke chamber wall directly serves as a magnetocurrent radiation source, eliminating the need for any additional independent conductor traces or dielectric support frame inside the smoke chamber. This reduces the number of components and the accumulation of assembly tolerances, while also avoiding the risk of localized overheating due to current accumulation at the bends of the bent conductors, providing a structural foundation for achieving uniform energy distribution within the smoke chamber.

[0021] In this embodiment, the radio frequency microwave source 5 is an electromagnetic wave generator with a frequency range of 300MHz to 300GHz, preferably using the Industrial, Scientific and Medical (ISM) band, with 915MHz being the preferred frequency and 2450MHz being the secondary choice. The radio frequency microwave source 5 includes an oscillator module, a power amplifier, a frequency synthesizer, a temperature sensor 3, and a control chip 4.

[0022] Specifically, the output of the oscillator module is connected to the input of the frequency synthesizer, the output of the frequency synthesizer is connected to the input of the power amplifier, and the output of the power amplifier is connected to the slit grid 12 of the smoke chamber 11 via a feed line, forming the main transmission path for the microwave signal. The signal output of the temperature sensor 3 is connected to the signal input of the control chip 4, and the control signal output of the control chip 4 is connected to the control terminals of the oscillator module and the power amplifier, respectively, forming a feedback adjustment loop for frequency control and power control. The frequency synthesizer dynamically corrects the output frequency of the oscillator module based on the instructions of the control chip 4 and the real-time detected load reflection signal; the control chip 4, based on the temperature signal fed back by the temperature sensor 3, adjusts the power supply voltage or PWM duty cycle of the power amplifier to achieve real-time control of the output power.

[0023] Furthermore, the oscillator module can be selected from a quartz crystal oscillator, a feedback oscillator, an LC sine wave oscillator, an RC oscillator, or a voltage-controlled oscillator (VCO) to generate an initial microwave signal. The signal is amplified to the required power by a power amplifier (typically 5W to 50W, which can be adjusted according to the cartridge capacity) and then transmitted to the smoke chamber 11 via a feeder.

[0024] The frequency synthesizer is connected between the oscillator module and the control chip. It is used to detect frequency drift caused by load changes during the insertion or heating of the cartridge 1, and correct the output frequency in real time to lock it to the preset operating frequency (e.g., 915MHz ± 5MHz).

[0025] Temperature sensor 3 is preferably a thermocouple or an infrared temperature measuring element. Its probe is set on the outer wall of the smoke chamber 11 or in the space of gap 23 to detect the temperature of the smoke chamber 11 in real time and feed the temperature signal back to the control chip 4. The control chip 4 realizes closed-loop temperature control by adjusting the power amplifier supply voltage or pulse width modulation (PWM) duty cycle according to a preset temperature curve (e.g., 180℃~280℃).

[0026] In this embodiment, the smoke chamber 11 is a cylindrical cavity 13 with an inner diameter ranging from 5 mm to 15 mm, a depth ranging from 20 mm to 50 mm, and a wall thickness ranging from 0.2 mm to 1.0 mm. The metal material is selected from copper, aluminum, iron, stainless steel, or their alloys, preferably copper with a silver-plated surface to reduce ohmic losses.

[0027] like Figure 2 As shown, the cylindrical smoke chamber 11 is bent outward by 90° at the opening and extended to a predetermined length, then bent 90° in the axial direction of the smoke chamber 11 and extended again to form a shell 14 that is conformally disposed with the smoke chamber 11. A gap space 23 is formed between the shell 14 and the smoke chamber 11. The above-mentioned bending and forming structure does not require additional connecting parts or seals, which reduces the accumulation of assembly tolerances and ensures the coaxiality and uniformity of the gap between the smoke chamber and the shell.

[0028] The geometric parameters of the slot grid 12 directly affect the coupling efficiency and field distribution uniformity of microwave energy within the smoke cavity. Specifically: The slit line includes multiple linear slits, which are connected sequentially by bending. There is a predetermined spacing between adjacent slits, and the length, width and spacing of each slit are determined according to the operating frequency of the radio frequency microwave signal.

[0029] Furthermore, when the slit lines are unfolded in a plane on the metal surface of the smoke chamber, each linear slit is connected end to end by a 90° bend to form a continuous slit grid 12; wherein, the length of each slit ranges from 9.65 mm to 18.64 mm, the width ranges from 0.69 mm to 0.87 mm, and the spacing between adjacent slits ranges from 0.65 mm to 1.08 mm.

[0030] The slit grid 12 is formed by laser etching or chemical etching on the cylindrical surface of the smoke chamber 11. For example... Figure 5 The image shown is a planar unfolded view of the metal surface of the smoke chamber in a preferred embodiment of the present invention. For a working frequency of 2.45 GHz, a total of 15 linear slots, numbered 121 to 1215, are etched on the metal surface. Specifically, the slots form a continuous slot grid by means of 90° bends and end-to-end connections. The specific geometric parameters of each slot are shown in Table 1. 121 17.68 0.70 0.65 122 16.33 0.69 0.65 123 16.93 0.70 0.76 124 18.12 0.74 0.70 125 17.82 0.76 0.70 126 18.64 0.74 0.70 127 18.12 0.74 0.70 128 17.73 0.76 0.70 129 17.06 0.77 0.97 1210 17.75 0.82 0.87 1211 17.08 0.87 0.87 1212 16.78 0.82 0.87 1213 16.90 0.87 1.08 1214 14.85 0.82 1.08 1215 9.65 0.87 — Table 1 In addition, a feeder slot 1216 with a length of 2.03 mm and a width of 0.88 mm is provided at the connection line of slots 126 and 127 for impedance matching.

[0031] Another typical parameter in the 915MHz band is: slot width 0.5mm–2mm, slot length 5mm–30mm, and slot spacing 3mm–10mm. The slot lines can also be in the form of a spiral shape with connected ends, a meandering serpentine shape, or a uniformly distributed ring array. The overall topology of the slot grid 12 makes the smoke chamber much smaller in electrical size than the operating wavelength (e.g., smoke chamber size <λ / 10), thereby generating a uniform electromagnetic field distribution in the near-field region.

[0032] The above structure, after finite element simulation and actual testing, shows that when the smoke cartridge is inserted into the smoke chamber, the deviation between the maximum and minimum electric field strength inside the smoke chamber is controlled within ±25%, which is considered "uniform". At the same time, the return loss of the smoke chamber is less than -10dB at the operating frequency, indicating that the radio frequency microwave energy is effectively coupled into the smoke chamber, and the radiated leakage power is less than 5% of the total input power.

[0033] In the above scheme, each slit in the slit grid acts as an independent radiating unit. By adjusting the length, width, and spacing of the slits (e.g., the specific parameters at 2.45 GHz mentioned above), the radiation phase and amplitude of each radiating unit in the circumferential direction of the cavity tend to be consistent, thereby forming a nearly uniform volumetric field distribution inside the smoke chamber. The deviation in electromagnetic force intensity and heating delay of the cartridge filling material at various points on the cross-section of the cavity can be controlled within ±25%, effectively overcoming the problem of local overheating or underheating caused by uneven field distribution in existing microwave-heated electronic cigarettes. Unlike conventional microwave heating structures that use metal strips or metal radiating sheets, the slit grid structure of this invention does not rely on the local electric field constraint near the conductor, but forms an overall balanced field distribution in the circumferential direction of the cavity, avoiding energy concentration in local areas, thereby achieving large-volume uniform heating without the need to add internal conductors or dielectric skeletons.

[0034] like Figures 6 to 9 The diagram shown is a structural schematic of the second preferred embodiment of the present invention. The difference between this embodiment and the first preferred embodiment is that the smoke chamber 11 is a metal surface disposed on the support structure 24. Slit lines are etched on this metal surface, and these slit lines are connected end-to-end or meandering to form a slit grid 12. The transmission line uses two parallel double-line structures composed of metal lines 181 and 181. Both metal lines pass through through holes 19 on the housing 14 and are electrically connected to two different points on the metal surface of the smoke chamber 11 to feed radio frequency microwave energy into the smoke chamber 11. The support structure 24 can be a ceramic substrate or a high-temperature resistant engineering plastic, used to fix the metal surface and ensure a uniform gap between it and the housing 14. The remaining structures (such as the housing 14, the corrugated structure 21, the fixing groove 22, etc.) are the same as in the first preferred embodiment and will not be described again here.

[0035] like Figure 10 As shown, the cartridge 1 includes a mouthpiece 31 and a cartridge filler 32. The cartridge filler 32 is inserted into the smoke chamber 11 through the circular opening 15 of the housing 14. The cartridge 1 is a disposable and replaceable part. When the cartridge filler is used up, the user can remove the old cartridge and insert a new cartridge to continue using it.

[0036] In this embodiment, the cartridge filler 32 is a dielectric material, whose molecules include nonpolar molecules (such as nonpolar tobacco materials) and polar molecules (such as tobacco materials containing moisture or polar additives). Under normal conditions, dipoles are arranged randomly, and the fields of positive and negative charges cancel each other out, resulting in electrical neutrality. When a radio frequency microwave electric field is applied, the nonpolar molecules transform into polar molecules. The polar molecules are oriented along the direction of the electric field and alternately reverse with the microwave frequency. Adjacent molecules rub against each other, and the radio frequency microwave energy is converted into the heat energy of the cartridge through mechanical motion.

[0037] Before use, the user inserts the cartridge 1 into the opening of the smoke chamber 11 until the bottom of the cartridge 1 contacts the inner wall of the smoke chamber 11. After powering on, the control chip 4 reads the initial temperature value of the temperature sensor 3. If it is lower than the preset threshold (e.g., 50°C), the radio frequency microwave source 5 is activated.

[0038] The oscillator module generates a continuous wave or pulse wave signal at a preset frequency (such as 915 MHz or 2450 MHz), which is amplified by a power amplifier to a typical value of 20W and transmitted to the slot grid 12 of the smoke chamber 11 via a feeder. The time-varying current and magnetic current on the slot grid 12 excite a near-field electromagnetic field inside the smoke chamber 11. This electromagnetic field exhibits a uniform energy flux density distribution within the smoke chamber 11, and the phase delay deviation of the electric field at each point is ≤±25%, thereby achieving synchronous heating.

[0039] Under the influence of an electromagnetic field, the dipoles in the cartridge filling material 32 repeatedly orient themselves at microwave frequencies, generating heat through intermolecular friction. Actual measurements show that at an input power of 20W, the temperature inside the smoke chamber rises to 220℃–250℃ within 3–8 seconds. At this point, the filling material releases inhalable smoke, which is then inhaled by the user through the cartridge's mouthpiece 31. Throughout the entire process, the internal temperature of the cartridge 1 remains well-uniform, with no open flame or combustion observed.

[0040] When the temperature sensor 3 detects that the temperature of the smoke chamber 11 exceeds the preset upper limit (e.g., 280°C), the control chip 4 automatically reduces the duty cycle of the power amplifier or shuts off the output. When the temperature drops back to the lower limit (e.g., 180°C), it restarts, and so on to maintain a constant temperature.

[0041] If the load impedance changes due to the replacement of cartridge 1 or differences in material batches, the frequency synthesizer will detect the reflection coefficient in real time and fine-tune the oscillator frequency to ensure that the smoke chamber is always in a resonant state and maintains the highest heating efficiency.

[0042] In addition to the cylindrical cavity mentioned above, the smoke chamber can also be designed as a rectangular, elliptical or irregular cross-section, such as the metal surface on the support structure 24. The layout of its slot grid can be adjusted according to the shape of the cavity.

[0043] Regarding the gap filling, the gap 23 between the housing 14 and the smoke chamber 11 can be filled with a solid medium (such as ceramic or polytetrafluoroethylene) with a dielectric constant of 2 to 10, in order to reduce the physical size of the smoke chamber or improve the matching characteristics.

[0044] Regarding the RF microwave source components, the oscillator module can be replaced with a direct digital frequency synthesizer (DDS) to provide more precise frequency tuning and fast frequency hopping. Temperature sensors can be configured to be distributed at multiple points to detect the temperature in the front, middle, and rear regions of the smoke chamber, further optimizing temperature field uniformity.

[0045] The power management module is integrated into the control chip 4. Its power comes from the rechargeable lithium battery 6 housed in the battery compartment 7. The battery voltage range is 3.7V to 7.4V, preferably a lithium-ion or lithium-polymer battery. The power management module is equipped with battery charge and discharge management circuitry, including overcharge protection, over-discharge protection, and short-circuit protection circuits to ensure safe operation. The standby power consumption of the entire device is less than 0.5W, and the maximum output power can reach 50W to meet the needs of different cartridge capacities and heating rates.

[0046] In summary, the heated non-combustible electronic cigarette device of the present invention uses a slit grid on the metal cavity wall as a unified structure for microwave coupling and field distribution. It eliminates the need for separate metal strips, metal radiating sheets, or dedicated dielectric support frames inside the smoke cavity, thus achieving efficient microwave energy feeding and uniform synchronous heating within the cavity even when the electrical size of the smoke cavity is much smaller than the working wavelength.

[0047] The technical scope of this invention is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this invention, and all such modifications and variations should fall within the protection scope of this invention.

Claims

1. A heated, non-combustible electronic cigarette using a radio frequency microwave source, characterized in that, include: Smoke cartridges; The smoke chamber is a metal cavity with one end open, used to accommodate the smoke cartridge. The metal surface of the smoke chamber is etched with slot lines, which are connected end to end or meander to form a slot grid. A radio frequency microwave source, wherein the radio frequency microwave source is connected to the metal surface of the smoke cavity via a feed line; A housing, which is fitted over the outside of the smoke chamber and has a gap space between it and the smoke chamber; The slotted grid is used to couple the microwave energy generated by the radio frequency microwave source into the interior of the smoke chamber to heat the smoke cartridge.

2. The electronic cigarette according to claim 1, characterized in that, The slit line includes multiple linear slits, which are connected sequentially by bending. There is a predetermined spacing between adjacent slits, and the length, width and spacing of each slit are determined according to the operating frequency of the radio frequency microwave signal.

3. The electronic cigarette according to claim 2, characterized in that, When the slit lines are unfolded in a plane on the metal surface of the smoke chamber, each linear slit is connected end to end by a 90° bend to form a continuous slit grid; wherein, the length of each slit ranges from 9.65 mm to 18.64 mm, the width ranges from 0.69 mm to 0.87 mm, and the distance between adjacent slits ranges from 0.65 mm to 1.08 mm.

4. The electronic cigarette according to claim 1, characterized in that, The feed line is a coaxial line, with the inner conductor passing through a hole in the housing and electrically connected to the metal surface of the smoke chamber, and the outer conductor of the coaxial line electrically connected to the housing; or, the feed line is a parallel double line, with both metal wires of the parallel double line passing through a hole in the housing and electrically connected to the metal surface of the smoke chamber.

5. The electronic cigarette according to claim 3, characterized in that, The slotted grid includes multiple slots, each of which serves as an independent radiation unit, coupling the electromagnetic energy of the radio frequency microwave source into the smoke cavity.

6. The electronic cigarette according to claim 1, characterized in that, The housing has an opening through which the smoke cartridge passes, and a corrugated structure is etched on the opening surface to suppress radio frequency microwaves from radiating outward along the opening.

7. The electronic cigarette according to claim 1, characterized in that, The radio frequency microwave source includes an oscillator module, a power amplifier, a frequency synthesizer, and a control chip; the output of the oscillator module is connected to the input of the frequency synthesizer, the output of the frequency synthesizer is connected to the input of the power amplifier, and the output of the power amplifier is connected to the smoke chamber via a feed line; the frequency synthesizer detects the frequency offset caused by load changes in real time according to the instructions of the controlled chip, and corrects the output frequency of the oscillator module to lock it to the preset operating frequency.

8. The electronic cigarette according to claim 7, characterized in that, It also includes a temperature sensor, which is disposed on the outer wall of the smoke chamber, in the gap space, or on the inner wall of the smoke chamber, for real-time detection of the temperature of the smoke chamber and feedback of the detected temperature signal to the control chip; the control chip performs closed-loop control of the heating temperature of the smoke chamber by adjusting the power supply voltage or pulse width modulation duty cycle of the power amplifier based on the comparison result of the received temperature signal and the preset temperature curve.

9. The electronic cigarette according to claim 1, characterized in that, The radio frequency microwave source operates in the ISM band, which includes 915MHz or 2450MHz.

10. The electronic cigarette according to claim 1, characterized in that, The gap between the smoke chamber and the shell is filled with a solid or liquid medium, the dielectric constant of which is in the range of 2 to 10.

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