Electronic cigarette and microphone structure thereof
By adopting a combined structure of conductive shell, piezoelectric film and circuit board in the electronic cigarette head, combined with the principle of piezoelectric and parallel plate capacitance, the problems of the influence and complex structure of the e-liquid in the existing technology are solved, and low power consumption is achieved , simplified structure and high sensitivity detection effect.
Patent Information
- Application Number
- CN202420770051.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-12
- Publication Date
- 2024-12-10
- Estimated Expiration
- 2034-04-12
AI Technical Summary
In the existing electronic cigarette head structure, capacitive microphone heads are easily affected by e-liquid, resulting in reduced sensitivity. The piezoelectric microphone heads are complex in structure and high in manufacturing cost, and the overall stability is insufficient.
Using a combined structure of conductive shell, piezoelectric film and circuit board, the piezoelectric film is protected through the tubular structure of the conductive shell, simplifying the structure and improving stability. Using the combination of piezoelectric film and parallel plate capacitance principles, a capacitor digital conversion circuit is set up to improve the Detect sensitivity and switch signal acquisition through analog switch time-sharing to avoid crosstalk.
It achieves no oil leakage risk, low power consumption, simplified structure, reduced manufacturing costs and improved stability, while improving detection sensitivity and accuracy, and reducing overall power consumption by an order of magnitude.
Smart Images
Figure CN222129382U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of electronic cigarettes, and in particular to an electronic cigarette and a microphone structure thereof. Background Art
[0002] The electronic cigarette microphone is a device used to detect the user's smoking action in the electronic cigarette. Currently there are two types: capacitive and piezoelectric.
[0003] The structure of the capacitive electronic cigarette microphone is a through hole on the top of the metal shell, and a breathable metal sheet, an insulating pad, and a conductive layer are arranged inside from top to bottom. The bottom of the shell is a PCB board. The copper on the front of the PCB board is connected to the film through a conductive bracket, and the copper on the back of the PCB is connected to the breathable metal sheet through the metal shell. The conductive bracket and the metal shell are insulated from each other by an insulating ring. The metal shell needs to be connected to the smoke outlet of the electronic cigarette. When the user smokes, the airway forms a negative pressure that drives the film to move toward the metal sheet through the air holes on the metal sheet. The distance between the film and the metal sheet decreases, and the mutual capacitance increases. The front of the PCB board is a detection chip, which is detected based on the frequency method. The resistor R is combined with the capacitor C constructed between the film and the metal sheet to form an RC oscillation. The change in mutual capacitance causes the oscillation frequency to change, and the switch signal is output through the threshold comparison. In this type of structure, there is a gap between the breathable metal sheet and the film, and the smoke oil can easily enter the gap, affecting the deformation of the conductive film, resulting in a decrease in the sensitivity of the microphone or even failure.
[0004] The sensor of the piezoelectric microphone consists of a piezoelectric film in the middle and electrodes at both ends. Through the piezoelectric effect, the negative pressure generated by smoking acts on the sensor, causing the film to deform and generate voltage output. Since the piezoelectric material does not require power supply, only the signal measurement circuit needs power supply, the power consumption is lower than that of the capacitive type, and there is no risk of oil leakage.
[0005] CN219396290U provides a piezoelectric sensor microphone structure, in which the entire assembly structure of the piezoelectric sensor is arranged in a packaging shell, the assembly structure includes a substrate and a piezoelectric sensing layer fixedly connected to the substrate, a back cavity penetrating the substrate is arranged on the substrate, the piezoelectric sensing layer covers the back cavity, the piezoelectric sensing layer includes a first dielectric layer fixedly connected to the substrate, a piezoelectric dielectric layer covering the first dielectric layer, a lower electrode layer covering the first dielectric layer, a piezoelectric sensitive film layer covering the lower electrode layer, and an upper electrode layer arranged on the piezoelectric sensitive film layer, the electrode layer is led out through an electrical lead-out element, the assembly structure is fixed on the substrate and soldered to the printed circuit board by soldering, the back cavity of the assembly structure is opposite to the air vent, the overall structure is relatively complex, and there are disadvantages in manufacturing cost and assembly. Utility Model Content
[0006] The utility model aims to improve the deficiencies of the prior art and provides an electronic cigarette microphone structure and an electronic cigarette using the microphone structure.
[0007] The electronic cigarette microphone structure of the utility model comprises a conductive shell, a piezoelectric film, and a circuit board; the piezoelectric film is connected to the smoke outlet of the electronic cigarette, and an upper electrode and a lower electrode are respectively arranged on the upper and lower surfaces of the piezoelectric film, and the upper electrode and the lower electrode serve as signal output electrodes of the piezoelectric film; the piezoelectric film is arranged in the conductive shell, and the upper electrode is electrically connected to the circuit board through the shell of the conductive shell, and a conductive bracket insulated from the conductive shell is arranged in the conductive shell, and the lower electrode is electrically connected to the circuit board through the conductive bracket; at least a piezoelectric measurement branch and a processing module are arranged on the circuit board, and the piezoelectric measurement branch is provided with a signal amplifier for amplifying the output signal of the piezoelectric film, and the processing module is electrically connected to the piezoelectric measurement branch.
[0008] The advantages of the microphone structure of the utility model are:
[0009] (1) Compared with capacitive microphones, piezoelectric film is filled between the upper electrode and the lower electrode, so there is no risk of failure due to oil leakage. At the same time, the passive self-generation based on piezoelectric materials can reduce power consumption compared with capacitive microphones.
[0010] (2) Compared with the piezoelectric microphone, the upper electrode is electrically connected to the circuit board by the shell of the conductive shell, and the lower electrode is electrically connected to the circuit board by the conductive bracket. The overall structure is simplified and compact, the manufacturing cost is low, and the overall stability is strong.
[0011] As an improved solution, the conductive shell is a tubular structure, the piezoelectric film is located in the conductive shell to form protection, the top tube wall of the conductive shell is bent inwards and pressed against the upper electrode on the top surface of the piezoelectric film, and a first air vent is formed to connect the smoke outlet and the piezoelectric film. The top tube wall of the conductive shell is bent inwards and directly pressed against the upper electrode, so as to further simplify the structure and process and improve stability. In terms of simplification and stability, further, the top tube wall of the conductive shell is bent inwards and pressed against the bottom surface of the circuit board, and the upper electrode is connected to the copper cladding below the circuit board such as the PCB through the conductive shell, and the bending at both ends is used to achieve the upper and lower direction limit. On this basis, further, the conductive bracket is sandwiched between the piezoelectric film and the circuit board to support and electrically connect the lower electrode on the bottom surface of the piezoelectric film. On the one hand, the lower electrode is connected to the copper cladding above the PCB through the conductive bracket, and on the other hand, the conductive bracket supports the piezoelectric film and the PCB to the bending and pressing at both ends of the shell. In order to achieve reliable insulation between the conductive bracket and the conductive shell, an insulating ring is provided between the conductive bracket and the inner side wall of the conductive shell.
[0012] In the microphone structure of the utility model, a second air hole is provided on the circuit board to balance the air pressure.
[0013] As another improvement scheme, a capacitance measurement branch is provided on the circuit board, and the capacitance measurement branch includes at least a capacitance-to-digital conversion circuit of a coupling processing module. The capacitance-to-digital conversion circuit is also electrically connected to the upper electrode through the shell of the conductive shell, and is electrically connected to the lower electrode through a conductive bracket. The upper electrode and the lower electrode serve as signal output electrodes of the piezoelectric film and sensing electrodes of the parallel plate capacitance sensor. The piezoelectric measurement branch and the capacitance measurement branch both obtain electrical signals from the upper electrode and the lower electrode and input them into the processing module. In this solution, the upper electrode and the lower electrode are reused as the signal output electrode of the piezoelectric film and the sensing electrode of the parallel plate capacitance sensor, so as to achieve structural compounding. The piezoelectric measurement branch and the capacitance measurement branch both obtain the electrical signal input processing module from the upper electrode and the lower electrode, so as to achieve circuit compounding. The sensor volume is minimized, and the microphone structure and circuit can be greatly simplified. At the same time, the sensor can achieve the pressure detection effect based on the piezoelectric effect, and can also make up for the defect that the piezoelectric material cannot detect the static force based on the parallel plate capacitance principle; or, the piezoelectric signal is used as the wake-up, and after the wake-up, the mutual capacitance signal between the two plates is collected based on the capacitance digital conversion circuit, and the smoking signal is detected by the change of the mutual capacitance signal. On the one hand, the overall power consumption of the microphone can be reduced by one order of magnitude, and on the other hand, the capacitance digital conversion circuit (CDC), such as ADI 7142 and ADI 7147, adopts a method of charging and discharging the measured capacitance multiple times and comparing it with the reference capacitance by using a Δ-Σ modulation method (see: US Patent No. 5,836,664). Number:5,134,401) directly converts the measured capacitance value into a digital value, which can increase the measurement sensitivity of the capacitance to 1ff level, thereby achieving the purpose of improving accuracy. In this solution, the frequency range of the excitation signal input to the upper electrode or the lower electrode of the capacitance digital conversion circuit can be configured to be different from the frequency range of the output signal of the piezoelectric film, and the system can achieve signal differentiation processing according to the difference in frequency.
[0014] As a further improvement of this solution, an analog switch is also provided on the circuit board. The upper electrode and the lower electrode are connected to the piezoelectric measurement branch and the capacitive measurement branch in a time-sharing manner through the switching of the analog switch. By setting the analog switch, the output acquisition of the piezoelectric film and the application of the capacitive excitation are switched in a time-sharing manner through the analog switch, thereby avoiding the crosstalk problem between the output signal of the piezoelectric film and the excitation signal of the sensor. At the same time, the chip is more convenient for time-sharing control with the help of the analog switch.
[0015] As another improvement of this solution, the upper electrode and / or the lower electrode is arranged on the side of the piezoelectric film by silk screen printing or evaporation. The silk screen printing or evaporation process can allow the electrode to be attached to the piezoelectric film in an extremely thin state, thereby preventing the electrode from affecting the deformation performance of the film.
[0016] An electronic cigarette is also provided, comprising the above-mentioned electronic cigarette microphone structure. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 A schematic diagram of the structure of the microphone is shown;
[0018] Figure 2 An exploded diagram of the microphone structure is shown;
[0019] Figure 3 Shows the explosion diagram of the microphone structure with the addition of a breathable metal sheet
[0020] Figure 4 Shows a schematic diagram of a circuit composed of discrete components;
[0021] Figure 5 A curve diagram of piezoelectric signal changes during smoking is shown;
[0022] Figure 6 A graph showing the change in capacitance after smoke oil accumulates on the piezoelectric film;
[0023] Figure 7 A schematic diagram of adding an analog switch circuit is shown; DETAILED DESCRIPTION
[0024] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.
[0025] like Figure 1 As shown, the electronic cigarette microphone includes a housing 100 , an insulating ring 200 , a piezoelectric film 300 , a conductive support 400 , and a circuit board 500 .
[0026] like Figure 1 , 2 As shown, the piezoelectric film 300 is composed of an upper electrode 310, a piezoelectric material 320, and a lower electrode 330; the circuit board 500 is composed of an upper copper clad layer 510, a substrate 520, and a lower copper clad layer 530; the upper electrode 310 of the piezoelectric film 300 is coupled to the lower copper clad layer 530 of the circuit board 500 through the housing 100; the lower electrode 330 of the piezoelectric film 300 is coupled to the upper copper clad layer 510 of the circuit board 500 through the conductive support 400; the conductive support 400 and the inner side wall of the conductive housing 100 are separated by an insulating ring 200 to achieve reliable insulation between the conductive support 400 and the conductive housing 100.
[0027] like Figure 3 As shown, a permeable metal sheet 110 is disposed between the piezoelectric film 300 and the housing 100 , and the upper electrode 310 of the piezoelectric film 300 is coupled to the lower copper clad 530 of the circuit board 500 through the permeable metal sheet 110 and the housing 100 .
[0028] like Figure 4As shown, the piezoelectric film includes an upper electrode 310 , a piezoelectric material 320 , and a lower electrode 330 . The upper electrode 310 and the lower electrode 330 are coupled to a signal amplifier 700 , a capacitance-to-digital conversion circuit 800 , and a processing module 900 .
[0029] like Figure 4 , 5 As shown, when someone smokes, the piezoelectric film 300 will be deformed due to negative pressure, and an electrical signal will be formed due to the piezoelectric effect of the piezoelectric material 320, and a wake-up judgment threshold X is set. At T2, the processing module 900 collects the electrical signal amplified by the signal amplifier 700 to reach the wake-up threshold X, and wakes up the processing module 900; after the processing module 900 wakes up, the capacitance-to-digital conversion circuit 800 collects the mutual capacitance signal between the upper electrode 310 and the lower electrode 330, and sets the threshold Y for smoking judgment. At T3, the capacitance value collected by the capacitance-to-digital conversion circuit 800 reaches the threshold Y for smoking judgment, and the processing module 900 sends a smoking signal.
[0030] like Figure 6 As shown, the capacitance change value Y1 is set as the threshold value for smoking judgment. During the T3 period, since the piezoelectric film is connected to the airway, the smoke oil slowly adheres to the side of the piezoelectric film connected to the airway, which affects the capacitance. The capacitance change caused by the accumulation of smoke oil is slow. During the T4 period, the capacitance change caused by smoking is a sudden change, and the change is greater than the threshold value Y1 for smoking judgment, and the processing module 900 sends a smoking signal.
[0031] like Figure 7 As shown, the upper electrode 310 and the lower electrode 330 are coupled to the signal amplifier 700 and the capacitance digital conversion circuit 800 through the switch array 600; the analog switch K1 connects to the line 1, and the analog switch K2 connects to the line 3, and the upper electrode 310 and the lower electrode 330 are connected to the signal amplifier 700 through the analog switches K1 and K2. When the negative pressure generated by smoking causes the piezoelectric film 300 to deform, an electrical signal is formed due to the piezoelectric effect of the piezoelectric material 320. The electrical signal is amplified by the signal amplifier 700 and then input into the processing module 900 to wake up the processing module 900; the analog switch K1 connects to the line 2, and the analog switch K2 connects to the line 4, and the upper electrode 310 and the lower electrode 330 are connected to the capacitance digital conversion circuit 800 through the analog switches K1 and K2. The capacitance digital conversion circuit 800 collects the mutual capacitance signal between the upper electrode 310 and the lower electrode 330, and the processing module 900 outputs a smoking judgment signal based on the change of the mutual capacitance signal.
[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit the protection scope of the utility model. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in this field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the utility model.
Claims
1. An electronic cigarette microphone structure, characterized in that: It includes a conductive shell, a piezoelectric film, and a circuit board; The piezoelectric film is connected to the smoke outlet of the electronic cigarette, and an upper electrode and a lower electrode are respectively arranged on the upper and lower surfaces of the piezoelectric film, and the upper electrode and the lower electrode serve as signal output electrodes of the piezoelectric film; The piezoelectric film is arranged in a conductive shell, the upper electrode is electrically connected to the circuit board through the shell of the conductive shell, a conductive bracket insulated from the conductive shell is arranged in the conductive shell, and the lower electrode is electrically connected to the circuit board through the conductive bracket; At least a piezoelectric measurement branch and a processing module are arranged on the circuit board. The piezoelectric measurement branch is provided with a signal amplifier for amplifying the output signal of the piezoelectric film. The processing module is electrically connected to the piezoelectric measurement branch.
2. The electronic cigarette microphone structure according to claim 1, characterized in that: The conductive shell is a tubular structure, the piezoelectric film is located in the conductive shell, the top tube wall of the conductive shell is bent inwardly and crimped to the upper electrode on the top surface of the piezoelectric film, and a first air hole is formed to connect the smoke outlet duct and the piezoelectric film.
3. The electronic cigarette microphone structure according to claim 2, characterized in that: The top tube wall of the conductive shell is bent inwardly and pressed against the bottom surface of the circuit board.
4. The electronic cigarette microphone structure according to claim 2 or 3, characterized in that: The conductive support is sandwiched between the piezoelectric film and the circuit board to support and electrically connect the lower electrode on the bottom surface of the piezoelectric film.
5. The electronic cigarette microphone structure according to claim 4, characterized in that: An insulating ring is arranged between the conductive bracket and the inner side wall of the conductive shell to separate them.
6. The electronic cigarette microphone structure according to claim 1, characterized in that: The circuit board is provided with a second vent hole.
7. The electronic cigarette microphone structure according to claim 1, characterized in that: A capacitance measurement branch is provided on the circuit board, and the capacitance measurement branch at least includes a capacitance-to-digital conversion circuit of a coupling processing module. The capacitance-to-digital conversion circuit is also electrically connected to the upper electrode through the shell of the conductive shell, and is electrically connected to the lower electrode through a conductive bracket. The upper electrode and the lower electrode serve as multiplexed electrodes for signal output electrodes of the piezoelectric film and sensing electrodes of the parallel plate capacitance sensor. The piezoelectric measurement branch and the capacitance measurement branch both obtain electrical signals from the upper electrode and the lower electrode and input them into the processing module.
8. The electronic cigarette microphone structure according to claim 6, characterized in that: The circuit board is also provided with an analog switch, and the upper electrode and the lower electrode are switched on the piezoelectric measurement branch and the capacitance measurement branch in a time-sharing manner through the switching of the analog switch.
9. The electronic cigarette microphone structure according to claim 6, characterized in that: The upper electrode and / or the lower electrode are arranged on the side of the piezoelectric film by screen printing or evaporation.
10. An electronic cigarette, characterized in that: It comprises the electronic cigarette microphone structure as described in any one of claims 1 to 9.