CN115039926A - MEMS-based electronic cigarette gas flow induction method, heating wire driving circuit and electronic cigarette - Google Patents

Abstract

The invention relates to an electronic cigarette flow induction method based on MEMS, a heating wire driving circuit and an electronic cigarette, wherein the method comprises the following steps: monitoring a real-time capacitance value in the cavity, judging whether the capacitance value in the cavity changes according to the real-time capacitance value and a preset reference capacitance value, and generating an electric signal when the capacitance value in the cavity changes; and outputting the electric signal to the outside of the cavity for processing. The electronic cigarette smoking device comprises an electronic cigarette, an air flow sensor, a micro-electromechanical system (MEMS) and a controller, wherein the electronic cigarette is provided with the air flow sensor, the MEMS is arranged on the controller, the controller is used for monitoring whether the air flow inside the electronic cigarette changes or not in real time, if so, the internal capacitance value of the MEMS based air flow sensor changes, an electric signal is generated, the electric signal is output to the outside of the MEMS based air flow sensor for identification, whether the air flow is a user smoking action or not is judged, and in addition, when the user smoking action is carried out, corresponding smoke volume is provided according to the size of the electric signal. The recognition accuracy is high, misjudgment is not easy to occur, the influence of environmental factors is small, and the service life is long.

Description

MEMS-based electronic cigarette airflow sensing method, heating wire drive circuit and electronic cigarette

technical field

The invention relates to the technical field of electronic cigarettes, and more particularly, to a MEMS-based electronic cigarette airflow sensing method, a heating wire driving circuit and an electronic cigarette.

Background technique

Electronic cigarettes are a cigarette substitute consisting of batteries, chips, atomizers and other accessories. When the electronic cigarette is in use, by sensing the smoking action of the user, the atomizer can turn the special e-liquid into vapor for the user to smoke by atomization. Because the content of harmful substances such as tar, carbon monoxide and nitric acid in the vapor is low, e-cigarettes are favored by users.

The traditional electronic cigarette uses the microphone head structure to detect the user's smoking action. The microphone head structure is a common capacitor. When the user smokes, the microphone head structure is deformed and the capacitance changes. The heating wire heats up and atomizes the e-liquid for the user to smoke. However, the accuracy of the microphone head structure is not increased, which is easy to be misunderstood, and cannot accurately provide the corresponding smoke volume according to the smoking action of the user. It is easily affected by environmental factors and has a short service life.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention lies in the problems of inaccuracy of the existing microphone head structure and short service life. In view of the above-mentioned defects of the prior art, a MEMS-based electronic cigarette, method, chip and electronic cigarette are provided.

The technical solution adopted by the present invention to solve the technical problem is to construct a MEMS-based electronic cigarette heating wire drive circuit, including:

The first module composed of the air flow sensor package based on the MEMS process is used to monitor whether the capacitance value in the cavity changes, and generate an electrical signal when the change occurs;

a second module packaged by a heating wire driving control chip, used for judging whether it is a smoking action of the user according to the electrical signal, and generating an indication signal when it is a smoking action;

The airflow sensor based on the MEMS process and the heating wire drive control chip are both independent package structures; the output end of the airflow sensor based on the MEMS process is electrically connected to the input end of the heating wire drive control chip; the The bias voltage terminal of the airflow sensor of the MEMS process is electrically connected to the bias voltage terminal of the heating wire driving control chip.

Further, the first module includes: a package substrate, a top cover and the airflow sensor based on the MEMS process; the airflow sensor based on the MEMS process and the top cover are both disposed on the package substrate; the The airflow sensor based on the MEMS process is located between the top cover and the package substrate.

Further, the packaging substrate is provided with an air inlet hole corresponding to the position of the airflow sensor based on the MEMS process; an air cavity is formed between the packaging substrate and the top cover; the top cover is far away from the inlet and outlet. The air hole is provided with an air outlet; the air inlet and the air cavity are communicated with the air outlet.

Further, the first module further includes pins arranged on the side of the package substrate away from the top cover; the bias voltage terminal and the output terminal of the airflow sensor based on the MEMS process are both the same as the The pins are electrically connected.

The present invention provides a MEMS-based electronic cigarette airflow sensing method, comprising the following steps:

Monitoring the real-time capacitance value in the cavity, judging whether the capacitance value in the cavity changes according to the real-time capacitance value and the preset reference capacitance value, and generating an electrical signal when the change occurs;

The electrical signal is output outside the cavity for processing.

Further, the step: judging whether the capacitance value in the cavity changes according to the real-time capacitance value and the preset reference capacitance value, and generating an electrical signal when the change occurs, specifically including:

Calculate the capacitance difference according to the real-time capacitance value and the preset reference capacitance value;

If the capacitance difference is not 0, an electrical signal is generated;

If the capacitance difference is 0, no electrical signal is generated.

Further, the capacitance difference value is a difference value between the reference capacitance value and the real-time capacitance value.

Further, it also includes the steps:

measuring the frequency of the electrical signal;

Determine whether the electrical signal is generated by the user's smoking action according to the frequency, and if so, generate an indication signal;

Control the electronic cigarette to switch to the working state.

Further, the indication signal is a heating wire driving signal.

The present invention provides an electronic cigarette, comprising the electronic cigarette heating wire driving circuit described in any one of the foregoing.

The beneficial effect of the present invention is that: using a MEMS-based airflow sensor to monitor in real time whether there is an airflow change inside the electronic cigarette, if so, the internal capacitance value of the MEMS-based airflow sensor changes, and an electrical signal is generated, and the electrical signal is output to the electronic cigarette based on The outside of the MEMS airflow sensor is identified to determine whether the airflow is a smoking action of the user, and when it is a smoking action of the user, the corresponding amount of smoke is provided according to the magnitude of the electrical signal. The recognition accuracy is high, misjudgment is not easy to occur, the environmental factors are less affected, and the service life is long.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the present invention will be further described below with reference to the accompanying drawings and embodiments. Ordinary technicians can also obtain other drawings based on these drawings without creative labor:

1 is a flowchart of a MEMS-based electronic cigarette airflow sensing method according to an embodiment of the present invention;

2 is a schematic structural diagram of an electronic cigarette heating wire driving circuit according to an embodiment of the present invention;

3 is a schematic structural diagram of a first module according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of an air flow direction according to an embodiment of the present invention.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the following will be described clearly and completely in combination with the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, and Not all examples. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

As shown in FIG. 1 , an embodiment of the present invention provides a MEMS-based electronic cigarette airflow sensing method, including the following steps:

S100: monitor the real-time capacitance value in the cavity, determine whether the capacitance value in the cavity changes according to the real-time capacitance value and the preset reference capacitance value, and generate an electrical signal when the change occurs;

S200: Output the electrical signal to the outside of the cavity for processing.

When the air pressure difference occurs in the cavity of the airflow sensor based on the MEMS process, its capacitance will also change. The airflow sensor based on the MEMS process monitors the capacitance value in its cavity in real time, and compares the real-time capacitance value with the preset reference capacitance value. If there is a change, an electrical signal is generated, and the airflow sensor based on the MEMS process outputs the electrical signal to the The external control chip identifies and completes the airflow sensing process. The external control chip judges whether the electric signal is a smoking action of the user, and when it is a smoking action of the user, according to the frequency of the electric signal, it outputs the corresponding amount of smoke for the user to smoke. The airflow sensor based on MEMS technology is used to sense airflow changes, which has high recognition accuracy, is not prone to misjudgment, has less influence from environmental factors, and has a long service life.

In a further embodiment, the step: judging whether the capacitance value in the cavity changes according to the real-time capacitance value and the preset reference capacitance value, and generating an electrical signal when the change occurs, specifically including:

Calculate the capacitance difference according to the real-time capacitance value and the preset reference capacitance value;

If the capacitance difference is not 0, an electrical signal is generated;

If the capacitance difference is 0, no electrical signal is generated.

Preferably, the capacitance difference value is the difference between the reference capacitance value and the real-time capacitance value.

The preset reference capacitance value is set as C ₀ , the real-time capacitance value is set as C ₁ , and the capacitance difference value is set as C _difference , then the capacitance difference value C _difference =C ₀ −C ₁ . Under normal conditions, C ₀ is equal to C ₁ . If the C _{difference is} not 0, an electrical signal is generated; if the C _difference is 0, no electrical signal is generated, and the airflow sensor based on the MEMS process continues to monitor the internal airflow change of the electronic cigarette.

In a further embodiment, it also includes the steps:

measure the frequency of electrical signals;

Determine whether the electrical signal is generated by the user's smoking action according to the frequency, and if so, generate an indication signal;

Control the electronic cigarette to switch to working state.

The capacitance change of the air flow sensor based on the MEMS process of the present application is similar to the generation factor of the capacitance change of the traditional microphone head, that is, the difference in air pressure causes the change of the spacing inside the air flow sensor based on the MEMS process, and the capacitance change occurs. When the user smokes, the distance increases, and when the user blows, the distance decreases. The relationship between the capacitance value and the distance is: C=εA/d, where C is the capacitance value, ε is the dielectric constant of the isolation medium, and A is the overlapping surface area between the conductive film and the backplane. Among them, when the user smokes, the distance increases, the capacitance value becomes smaller, C ₀ is greater than C ₁ , and the C _difference is a positive value. When the user exhales, the distance decreases, and its capacitance value increases, _C0 is less than C1, and the C _difference is negative. When the C _difference is a positive value or a negative value, the corresponding electrical signal frequency is also different, and the user's smoking action is identified by the electrical signal frequency.

If the electrical signal is generated by the user's smoking action, an instruction signal is generated to control the heating wire to heat and atomize the e-liquid. If the electrical signal is not generated by the user's smoking action, no indication signal is generated, and the heating wire does not generate heat.

In a further embodiment, the indication signal is a heating wire driving signal.

The present invention provides a MEMS-based electronic cigarette heating wire drive circuit, as shown in FIG. 2 to FIG. 4 , including:

The first module 1 packaged by the airflow sensor 11 based on the MEMS process is used to monitor whether the capacitance value in the cavity changes, and generate an electrical signal when the change occurs;

The second module 2 packaged by the heating wire drive control chip 21 is used to judge whether it is a smoking action of the user according to the electrical signal, and generate an indication signal when it is a smoking action;

The airflow sensor 11 based on the MEMS process and the heating wire drive control chip 21 are both independent package structures; the output end of the airflow sensor 11 based on the MEMS process is electrically connected to the input end of the heating wire drive control chip 21; the airflow sensor 11 based on the MEMS process The bias voltage terminal of the heating wire is electrically connected to the bias voltage terminal of the heating wire driving control chip 21 .

The first module 1 and the second module 2 are separately packaged, which can further reduce the volume of each module and simplify the packaging process. When the air pressure difference occurs in the cavity of the airflow sensor 11 based on the MEMS process in the first module 1, its capacitance will also change. The airflow sensor 11 based on the MEMS process monitors the capacitance value in its cavity in real time, and compares the real-time capacitance value with the preset reference capacitance value. If there is a change, an electrical signal is generated, and the airflow sensor 11 based on the MEMS process converts the electrical signal The heating wire driving control chip 21 output to the second module 2 performs identification and completes the airflow induction process. The heating wire driving control chip 21 determines whether the electrical signal is a smoking action of the user, and when it is a smoking action of the user, according to the frequency of the electrical signal, it outputs a corresponding amount of smoke for the user to smoke. The airflow sensor 11 based on the MEMS process is used to sense airflow changes, with high recognition accuracy, less misjudgment, less influence from environmental factors, and long service life.

In a further embodiment, the first module 1 includes: a package substrate 12, a top cover 13 and an airflow sensor 11 based on a MEMS process; both the airflow sensor 11 and the top cover 13 based on the MEMS process are arranged on the package substrate 12; The airflow sensor 11 of the MEMS process is located between the top cover 13 and the package substrate 12 . The diameter or length and width of the top cover 13 are larger than the diameter or length and width of the package substrate 12 , so that the package substrate 12 can be completely installed in the top cover 13 , and the top cover 13 and the package substrate 12 are adhered by silica gel . The package structure of the second module 2 is similar to that of the first module 1 , except that the airflow sensor 11 based on the MEMS process is replaced with a heating wire driving control chip 21 . The first module 1 and the second module 2 are separately packaged, which can further reduce the volume of each module, simplify the packaging process, reduce the defective rate of the finished electronic cigarette performance, reduce the work intensity of the installer, and improve the performance of the electronic cigarette. Productivity.

In a further embodiment, the package substrate 12 is provided with an air intake hole 14 corresponding to the position of the airflow sensor 11 based on the MEMS process; an air cavity 15 is formed between the package substrate 12 and the top cover 13 ; the top cover 13 is far away from the intake air The hole 14 is provided with an air outlet 16 ; the air inlet 14 and the air cavity 15 are communicated with the air outlet 16 . When the user inhales, the gas enters the air cavity 15 from the air inlet hole 14 and then is discharged from the air outlet hole 16 .

In a further embodiment, the first module 1 further includes a pin 17 disposed on the side of the package substrate 12 away from the top cover 13 ; the bias voltage terminal and the output terminal of the airflow sensor 11 based on the MEMS process are both connected to the pin 17 electrical connection.

The present invention provides an electronic cigarette, including the electronic cigarette heating wire driving circuit as described above. The electronic cigarette uses a MEMS-based airflow sensor to monitor in real time whether there is an airflow change inside the electronic cigarette. If so, the internal capacitance value of the MEMS-based airflow sensor changes, and an electrical signal is generated to output the electrical signal to the MEMS-based airflow sensor. The outside of the device is identified to determine whether the airflow is a smoking action of the user, and when it is a smoking action of the user, the corresponding smoke amount is provided according to the magnitude of the electrical signal. The identification accuracy is high, misjudgment is not easy to occur, the environmental factors are less affected, and the service life is long.

It should be understood that, for those skilled in the art, improvements or changes can be made according to the above description, and all these improvements and changes should fall within the protection scope of the appended claims of the present invention.

Claims (10)

1. an electronic cigarette heating wire drive circuit based on MEMS, is characterized in that, comprises: The first module composed of the air flow sensor package based on the MEMS process is used to monitor whether the capacitance value in the cavity changes, and generate an electrical signal when the change occurs; a second module packaged by a heating wire driving control chip, used for judging whether it is a smoking action of the user according to the electrical signal, and generating an indication signal when it is a smoking action; The airflow sensor based on the MEMS process and the heating wire drive control chip are both independent package structures; the output end of the airflow sensor based on the MEMS process is electrically connected to the input end of the heating wire drive control chip; the The bias voltage terminal of the airflow sensor of the MEMS process is electrically connected to the bias voltage terminal of the heating wire driving control chip. 2 . The MEMS-based electronic cigarette heating wire driving circuit according to claim 1 , wherein the first module comprises: a package substrate, a top cover, and the MEMS-based airflow sensor; the MEMS-based The airflow sensor of the process and the top cover are both disposed on the packaging substrate; the airflow sensor based on the MEMS process is located between the top cover and the packaging substrate. 3 . The MEMS-based electronic cigarette heating wire driving circuit according to claim 2 , wherein the package substrate is provided with an air intake hole corresponding to the position of the airflow sensor based on the MEMS process; the package substrate An air cavity is formed between the top cover and the top cover; an air outlet hole is provided on the top cover away from the air inlet hole; the air inlet hole and the air cavity are communicated with the air outlet hole. 4. The MEMS-based electronic cigarette heating wire driving circuit according to claim 2, wherein the first module further comprises a pin disposed on the side of the package substrate away from the top cover; the Both the bias voltage terminal and the output terminal of the airflow sensor based on the MEMS process are electrically connected to the pins. 5. A MEMS-based electronic cigarette airflow sensing method, characterized in that: comprising the following steps: Monitoring the real-time capacitance value in the air cavity, judging whether the capacitance value in the cavity changes according to the real-time capacitance value and the preset reference capacitance value, and generating an electrical signal when the change occurs; The electrical signal is output to the outside of the air cavity for processing. 6. The MEMS-based electronic cigarette airflow sensing method according to claim 5, wherein the step is to determine whether the capacitance value in the cavity changes according to the real-time capacitance value and the preset reference capacitance value, and Generate electrical signals when changes occur, including: Calculate the capacitance difference according to the real-time capacitance value and the preset reference capacitance value; If the capacitance difference is not 0, an electrical signal is generated; If the capacitance difference is 0, no electrical signal is generated. 7 . The MEMS-based electronic cigarette airflow sensing method according to claim 6 , wherein the capacitance difference is the difference between the reference capacitance value and the real-time capacitance value. 8 . 8. The MEMS-based electronic cigarette airflow sensing method according to claim 5, further comprising the steps of: measuring the frequency of the electrical signal; Determine whether the electrical signal is generated by the user's smoking action according to the frequency, and if so, generate an indication signal; Control the electronic cigarette to switch to working state. 9 . The MEMS-based electronic cigarette airflow sensing method according to claim 8 , wherein the indication signal is a heating wire driving signal. 10 . 10. An electronic cigarette, characterized by comprising the electronic cigarette heating wire driving circuit according to any one of claims 6-9.

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