CN115005511A - Gas mist generating device and control method - Google Patents

Abstract

The application provides an aerosol generating device and a control method; wherein the aerosol-generating device comprises: a susceptor configured to be penetrated by a varying magnetic field to generate heat to heat an aerosol-generating article; an LC oscillator having an inductor coil configured to direct a varying current through the inductor coil to drive the inductor coil to generate a varying magnetic field; a comparator configured to compare an oscillation voltage of the LC oscillator with a preset value and output a pulse signal having the same frequency as the oscillation voltage according to a comparison result; a controller configured to receive the pulse signal and acquire an oscillation frequency of the LC oscillator by calculating a frequency of the pulse signal. Compared with the existing active sampling mode for acquiring the frequency, the mode that the power frequency of the controller needs to be increased to about dozens of MHz is adopted, and the power consumption of the controller is greatly reduced.

Description

Gas mist generating device and control method

Technical Field

The embodiment of the application relates to the technical field of heating non-combustion low-temperature smoking set, in particular to an aerosol generation device and a control method.

Background

Smoking articles (e.g., cigarettes, cigars, etc.) burn tobacco during use to produce tobacco smoke. Attempts have been made to replace these tobacco-burning products by making products that release compounds without burning.

An example of such a product is a heating device that releases a compound by heating rather than burning the material. For example, the material may be tobacco or other non-tobacco products, which may or may not include nicotine. In known devices, tobacco products are heated by an electromagnetic induction heated heater to generate an aerosol for smoking. In one prior art embodiment of the above heating device, the' 201580007754.2 patent proposes an induction heating device for heating a special cigarette product by electromagnetic induction; specifically, an induction coil and a capacitor are connected in series or in parallel to form an LC oscillation mode to form alternating current, so that the coil generates an alternating magnetic field to induce a receptor to heat a cigarette product. In the above known heating device, a comparator is usually used to detect the oscillating voltage, and then the control chip samples the above result to calculate the frequency of the LC oscillation. In implementation, because the frequency of LC oscillation is very high, about 200-400 KHz, the control chip can sample when the comparator outputs the result instantly, and the sampling speed of the control chip is increased to about tens of MHz to avoid missing the result signal output instantly by the comparator; further, the power consumption of the control chip in tracking the frequency of LC oscillation in this way is very large, and the processing of the main line process is affected, which is not preferable.

Disclosure of Invention

Based on the above problem of controlling a chip to actively sample for LC oscillation frequency with high power consumption, embodiments of the present application provide an aerosol-generating device configured to heat an aerosol-generating article to generate an aerosol for inhalation; the method comprises the following steps:

a susceptor configured to be penetrated by a varying magnetic field to generate heat to heat an aerosol-generating article;

an LC oscillator having an inductor coil configured to direct a varying current through the inductor coil to drive the inductor coil to generate a varying magnetic field;

a comparator configured to compare an oscillation voltage of the LC oscillator with a reference value and output a pulse signal having the same frequency as the oscillation voltage according to a comparison result;

a controller configured to receive the pulse signal and acquire an oscillation frequency of the LC oscillator by calculating a frequency of the pulse signal.

Compared with the existing active sampling mode, the mode that the power frequency of the controller needs to be increased to about dozens of MHz when the frequency is acquired by the controller through the passive pulse signal receiving and then the frequency calculation process is processed by the aerosol generation device, and the power consumption of the controller is greatly reduced.

In a preferred implementation, the controller is further configured to trigger an interrupt process of the controller when the pulse signal is received.

The term "interrupt/interrupt processing" is a control mode of a chip or a single chip or similar device, and specifically, when a CPU or a receiving process receives an "interrupt signal", other processes or tasks are temporarily stopped, and after a function or process corresponding to the "interrupt signal" is completed at an appropriate time, the original process or task is returned.

In a preferred implementation, the controller is configured to acquire the frequency of the pulse signal according to the interval time of the transition edge in the pulse signal.

The electrical basic term "transition edge" refers to the process of transitioning from one state to another when a signal is pulsed, and includes both the rising and falling edges described above. "rising edge" and "falling edge" are electrical base terms; here, "rising edge" is a rising change in the signal level from a low level to a high level; conversely, a "falling edge" is a falling change in signal level from a high level to a low level.

In a preferred implementation, the transition edges include a rising edge and a falling edge; the controller is configured to acquire the frequency of the pulse signal according to the interval time of adjacent rising edges or falling edges of the pulse signal.

In a preferred implementation, the controller includes a capture compare register for capturing transition edges of the pulse signal.

In a preferred implementation, the controller includes a counter for counting the number of transition edges captured by the capture compare register.

In a preferred implementation, the controller includes a timer for storing a time at which a transition edge is captured by the capture compare register.

In a preferred implementation, the controller is further configured to adjust the oscillation frequency of the LC oscillator so that the oscillation frequency of the LC oscillator remains the same as or substantially close to a preset frequency.

An embodiment of the present application also proposes a control method of an aerosol-generating device comprising:

a susceptor configured to be penetrated by a varying magnetic field to generate heat to heat an aerosol-generating article;

an LC oscillator having an inductor coil configured to direct a varying current through the inductor coil to drive the inductor coil to generate a varying magnetic field;

the method comprises the following steps:

comparing the oscillation voltage of the LC oscillator with a preset value, and outputting a pulse signal with the same frequency as the oscillation voltage according to a comparison result;

and receiving the pulse signal, and acquiring the oscillation frequency of the LC oscillator by calculating the frequency of the pulse signal.

In a preferred implementation, the method further comprises the following steps:

and adjusting the oscillation frequency of the LC oscillator so that the oscillation frequency of the LC oscillator is the same as or basically close to the preset frequency.

Drawings

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the figures in which like reference numerals refer to similar elements and which are not to scale unless otherwise specified.

Figure 1 is a schematic diagram of an aerosol-generating device provided by an embodiment of the present application;

FIG. 2 is a block diagram of one embodiment of the circuit of FIG. 1;

FIG. 3 is a schematic diagram of the basic components of one embodiment of the circuit of FIG. 2;

FIG. 4 is a schematic diagram of signals during oscillation of the LC oscillator of FIG. 3;

FIG. 5 is a block diagram of an MCU controller in one embodiment;

fig. 6 is a schematic structural diagram of an embodiment of an MCU controller.

Detailed Description

To facilitate an understanding of the present application, the present application is described in more detail below with reference to the accompanying drawings and detailed description.

An embodiment of the present application provides an aerosol-generating device, the configuration of which can be seen in fig. 1, including:

a chamber within which an aerosol-generating article a is removably received;

a magnetic field generator for generating a varying magnetic field; in the embodiment shown in fig. 1, the magnetic field generator is an induction coil L that generates a magnetic field by supplying an alternating current;

a susceptor 30, at least a portion of which extends within the chamber and is configured to inductively couple with the inductor L to generate heat when penetrated by the varying magnetic field to heat an aerosol-generating article a, such as a cigarette, to volatilize at least one component of the aerosol-generating article a to form an aerosol for smoking;

the battery cell 10 is a rechargeable direct current battery cell and can output direct current;

the circuit 20, which is electrically connected to the rechargeable battery cell 10 through a suitable electrical connection, is used for converting the direct current output from the battery cell 10 into an alternating current with a suitable frequency, and then supplying the alternating current to the inductance coil L.

The inductor L may comprise a helically wound cylindrical inductor coil, as shown in figure 1, depending on the arrangement in use of the product. The helically wound cylindrical inductor L may have a radius r in the range of about 5mm to about 10mm, and in particular the radius r may be about 7 mm. The length of the helically wound cylindrical inductor L may be in the range of about 8mm to about 14mm, with the number of turns of the inductor L being in the range of about 8 to 15 turns. Accordingly, the internal volume may be about 0.15cm ³ To about 1.10cm ³ Example (A) ofInside the enclosure.

In a more preferred implementation, the frequency of the alternating current supplied by the circuit 20 to the inductor L is between 80KHz and 400 KHz; more specifically, the frequency may be in the range of approximately 200KHz to 300 KHz.

In a preferred embodiment, the battery cell 10 provides a dc supply voltage in a range from about 2.5V to about 9.0V, and the battery cell 10 provides a dc current with an amperage in a range from about 2.5A to about 20A.

In a preferred embodiment, the susceptor 30 is generally in the shape of a pin or blade, which in turn is advantageous for insertion into the aerosol-generating article a; meanwhile, the susceptor 30 may have a length of about 12 mm, a width of about 4mm and a thickness of about 0.5 mm, and may be made of grade 430 stainless steel (SS 430). As an alternative embodiment, the susceptor 30 may have a length of about 12 millimeters, a width of about 5 millimeters, and a thickness of about 0.5 millimeters, and may be made of grade 430 stainless steel (SS 430). In other variations, the susceptor 30 may also be configured in a cylindrical or tubular shape; the interior space forms a chamber for receiving the aerosol-generating article a in use and generates an aerosol for inhalation by heating the periphery of the aerosol-generating article a. These susceptors may also be made from grade 420 stainless steel (SS420), as well as iron/nickel containing alloy materials such as permalloy.

In the embodiment shown in figure 1, the aerosol-generating device further comprises a support 40 for the arrangement of the inductor coil L and susceptor 30, the material of the support 40 may comprise a high temperature resistant non-metallic material such as PEEK or ceramic, etc. In practice, the inductor L is fixed by being wound around the outer wall of the bracket 40. Also, according to the hollow tubular shape of the holder 40, as shown in fig. 1, the tubular hollow part space thereof forms the above-mentioned chamber for receiving the aerosol-generating article a.

In alternative embodiments, the susceptor 30 is made of the above susceptor material, or is formed by plating, depositing, etc., a coating of susceptor material on the outer surface of a heat resistant substrate material such as ceramic.

The above structure and basic components of the circuit 20 in a preferred embodiment can be seen in fig. 2 to 3, including:

the parallel LC oscillator 24, specifically consisting of a capacitor C1 in parallel with the inductor L, is further oscillated by applying a pulsed voltage thereto to generate a varying current supplied to the inductor L, thereby generating a varying magnetic field to induce heating of the susceptor 30.

The transistor switch 23 includes a switching tube Q1, which is turned on and off alternately to conduct current between the battery cell 10 and the parallel LC oscillator 24 to oscillate the parallel LC oscillator 24, forming a varying current flowing through the inductor L, thereby generating a varying magnetic field in the inductor L. Of course, in the preferred embodiment shown in fig. 3, the switch Q1 is a conventional MOS switch, and the connected MOS switch is turned on/off according to the PWM driving signal received by the G-pole of the switch driver 22.

Further in the preferred embodiment, the on and off of the transistor switch 23 is controlled by a driving signal of the switch transistor driver 22. Of course, the driving signal of the switching tube driver 22 is generated based on the pulse control signal of the PWM system generated by the MCU controller 21. In the implementation shown in fig. 3, the switching tube driver 22 is a conventional FD2204 type switching tube driver, which is controlled by the MCU controller 21 in a PWM manner, and alternately sends high/low levels as driving signals from the 3 rd and 10 th I/O ports according to the pulse width of the PWM to control the on-time of the connected switching tube Q1, so that the parallel LC oscillator 24 oscillates and generates a magnetic field.

Specifically, fig. 4 shows the variation of the oscillating current/voltage within one period from time t1 to time t5 when the parallel LC oscillator 24 of the circuit 20 shown in fig. 3 is driven in a symmetric resonance mode with a 50% duty cycle; the method comprises the following steps:

s1, time period from t1 to t 2: the switching transistor driver 22 drives the transistor Q1 to be in saturation conduction by sending a PWM pulse driving signal to the G-pole of the transistor Q1. After the current i1 is switched on, the current i1 flows through the inductance coil L from the positive electrode of the battery cell 10, and the coil inductance does not allow the current to suddenly change; therefore, the inductor L is charged at time t1 to time t2 to form a linearly rising current i 1.

S2, time period from t2 to t 3: at time t2, the PWM pulse ends and MOS transistor Q1 turns off, and the current does not immediately change to 0 due to the inductive reactance of inductor L, but instead assumes the current i2 that charges capacitor C1 by charging capacitor C1.

Until time t3, the capacitor C1 is fully charged, and the current becomes 0; at this time, the magnetic field energy of the inductor L is completely converted into the electric field energy of the capacitor C1, a peak voltage is reached at both ends of the capacitor C1, and the voltage formed between the D electrode and the S electrode of the MOS transistor Q1 is actually the sum of the peak voltage of the anti-phase pulse and the positive output voltage of the battery cell 10.

S3, time period from t3 to t 4: the capacitor C1 discharges through the inductance coil L until the discharge is completed, i3 reaches the maximum value, the voltage at the two ends of the capacitor C1 gradually drops to disappear, and at the moment, the electric energy in the capacitor C1 is completely converted into the magnetic energy in the inductance coil L. The current flowing through the inductor L also varies stepwise due to the inductive reactance and is in the opposite direction to the above S1 and S2; the capacitor C1 discharges until the electromotive force across the inductor L reverses.

S4, time period from t4 to t 5: when the MOS tube Q1 is turned on again at the time t4, the inductance coil L and the filter capacitor C3 form backflow, the energy of the inductance coil L backflushs to the filter capacitor C3 to form a gradually-reduced current i4 until the period at the time t5 reduced to 0 is ended; and then the next oscillation cycle is started.

As can be understood from the above description, at the time t4, the D-pole/S-pole voltage of the MOS transistor Q1 crosses zero, and the MOS transistor Q1 is switched on/off during oscillation at the time when the D-pole/S-pole voltage crosses zero.

Further in the preferred implementation of fig. 3 and 4, the circuit 20 further comprises:

the frequency detection unit 25 and the MCU controller 21 cooperate to detect the oscillation frequency of the LC oscillator 24. In the implementation shown in fig. 3, the frequency detection unit 25 comprises a comparator U1; in the connection mode, the sampling terminal in-of the comparator U1 is connected to the LC oscillator 24 through a diode D1 to sample the voltage of the LC oscillator 24, and the sampling terminal in + is connected to the standard voltage Vcc to obtain the reference value Vref, and when the voltage sampled by the sampling terminal in-is higher than the reference value Vref of the comparator U1, a high level signal is output to the MCU controller 21.

Specifically, a schematic diagram of the output signal Vout of the comparator U1 is shown in fig. 4. When the oscillation voltage of the LC oscillator 24 is higher than the reference value Vref of the comparator U1, the output of the comparator U1 changes from the low level to the high level; when the oscillation voltage of the LC oscillator 24 falls below the reference value Vref of the comparator U1, the output of the comparator U1 changes from high to low.

As can be seen from fig. 4, the comparator U1 converts the "rising edge" and the "falling edge" of the oscillating voltage signal of the LC oscillator 24 into the pulse square wave signal Vout with the same period for outputting, and the MCU controller 21 receives the output signal Vout and measures the period of the pulse square wave to obtain the oscillating frequency of the LC oscillator 24.

The above "rising edge" and "falling edge" are electrical basic terms; here, "rising edge" is a rising change in the signal level from a low level to a high level; conversely, a "falling edge" is a falling change in signal level from a high level to a low level.

In the implementation of the present application, the MCU controller 21 implemented above does not actively sample the pulsed square wave signal Vout, but instead adopts a passive external interrupt processing mode; specifically, the pulse square wave Vout is sent to the MCU controller 21 as an external interrupt signal, and the MCU controller 21 temporarily stops other main line processes or tasks after receiving the signal, calculates the acquired frequency according to the received signal, and then returns to the main line process or task. The electrical term "interrupt/interrupt processing" is a control mode of a chip or a device similar to a single chip microcomputer, and specifically, when a CPU or a receiving process receives an "interrupt signal", other processes or tasks are temporarily stopped, and after a function or process corresponding to the "interrupt signal" is completed at an appropriate time, the original process or task is returned.

In a preferred embodiment, the MCU controller 21 determines the oscillation frequency by detecting the adjacent intervals of the pulsed square wave. For example, the oscillation period is calculated by the time difference between the start time t300 of the second of the two adjacent pulse square waves and the start time t100 of the first, and then the oscillation frequency is calculated by the oscillation period.

In other variant implementations, the above circuit 20 may also use a series LC oscillator instead of the above parallel LC oscillator 24 to oscillate to drive the inductance coil L to generate the varying magnetic field; correspondingly, in the implementation of matching, the LC oscillators connected in series are driven by a bridge circuit, for example, a half bridge including two switching tubes or a full bridge including four switching tubes, to realize inversion.

Further, after acquiring the frequency of the parallel LC oscillator 24 or the series LC oscillator, the MCU controller 21 may subsequently adjust the frequency or duty ratio of the output control signal, so that the oscillation frequency of the parallel LC oscillator 24 or the series LC oscillator is the same as or substantially close to the preset frequency.

In a preferred implementation, the MCU controller 21 calculates the acquisition frequency by combining the cycles of the pulse signals output by the timing acquisition comparator U1 in the external interrupt mode.

Fig. 5 in particular shows a block diagram of an MCU controller 21 with the above functions, including Capture compare registers CCR (Capture/compare register), counters CNT and timers 211. The MCU controller 21 with the above functional modules can be applied to STM32 singlechips, msp430 singlechips, British flyer XC866 singlechips and the like of HNB products.

In a general implementation, the method for the MCU controller 21 to calculate the acquired oscillation frequency according to the pulse signal output from the comparator U1 includes:

s10, when the capture comparison register CCR captures the jump edge of the pulse signal, the timer 211 starts to time, meanwhile, the counter CNT counts the captured jump edge, and the count value is stored in the capture comparison register CCR after the counting is finished;

s20, the MCU controller 21 calculates the frequency of the pulse signal captured by the capture comparison register CCR according to the saved count value and the duration of the pulse signal recorded by the timer 211.

The above electrical term "transition edge" is the process of transitioning from one state to another state when a signal is pulsed, and includes both the rising and falling edges described above. For example, it corresponds to the rising edge b31 of the pulse square wave signal in fig. 4 that momentarily rises to a high level or the falling edge b32 of the process that momentarily falls to a low level.

The MCU controller 21 processes the output signal of the comparator U1 in an external interrupt mode to acquire frequency, and the process of frequency calculation is processed only after receiving the pulse signal, so that the process of frequency acquisition in the operation composition is executed to be the same as the frequency of the pulse signal; the power consumption of the MCU controller 21 is greatly reduced compared to the conventional active sampling that is required to raise the MCU controller 21 to a frequency of about several tens of MHz.

Fig. 6 shows a schematic diagram of the MCU controller 21 capable of capturing the acquisition frequency of the pulsed square wave signal Vout by the above control manner of external interrupt. The MCU controller 21 is an STM32 singlechip; when this STM32 singlechip carries out above processing program, adopt following setting, include:

1. capture channel TIMx selection: the capture channels are ICs 1/2/3/4 in fig. 6, each TIMx has a corresponding capture compare register CCR1/2/3/4, and when capture occurs, the value of the counter CNT is latched into the corresponding capture register CCR; when only the pulse width of the input signal needs to be measured, one capture channel is used. The mapping of the input and capture channels is specifically configured by bits CCxS [1:0] of register CCMRx within the STM32 monolithic chip, not shown in FIG. 6.

2. Setting a prescaler: the ICx output signal is passed through a prescaler to determine how many events occur and to perform a capture. In particular this setting is also configured by the bit ICxPSC of the register CCMRx within the STM32 monolithic chip, not shown in fig. 6.

3. Capture register set: the signal ICxPS that passes through the prescaler is the final captured signal, and when capture occurs (the first time), the value of the counter CNT will be latched into the capture register CCR and a CCxI interrupt will also be generated, the corresponding interrupt bit CCxIF (in the SR register) will be set, and CCxIF can be cleared to 0 by software or by reading the value in CCR.

After the setting is completed, the step of acquiring the frequency of the pulse square wave Vout in the operation process of the STM32 singlechip comprises the following steps:

when a rising edge b31 occurs on the capture channel TIMx, the first capture occurs, and the value of the counter CNT is latched into the corresponding capture compare register CCR; a capture interrupt is also entered, a capture is recorded once in the interrupt service routine (which may be recorded with a flag variable), and the value in the capture compare register CCR is read into value 1. When a second rising edge b33 occurs, a second capture occurs, the value of the counter CNT will be latched into the capture compare register CCR again, and the capture interrupt is entered again; in the capture interrupt, the value of the capture compare register CCR is read into value3 and the capture record flag is cleared. By using the difference between value3 and value1, we can calculate the period (frequency) of the signal.

It should be noted that the description and drawings of the present application illustrate preferred embodiments of the present application, but are not limited to the embodiments described in the present application, and further, those skilled in the art can make modifications or changes according to the above description, and all such modifications and changes should fall within the scope of the claims appended to the present application.

Claims (10)

1. An aerosol-generating device configured to heat an aerosol-generating article to generate an aerosol; it is characterized by comprising:

a susceptor configured to be penetrated by a varying magnetic field to generate heat to heat an aerosol-generating article;

an LC oscillator having an inductor coil configured to direct a varying current through the inductor coil to drive the inductor coil to generate a varying magnetic field;

a comparator configured to compare an oscillation voltage of the LC oscillator with a reference value and output a pulse signal according to a comparison result;

a controller configured to receive the pulse signal and acquire an oscillation frequency of the LC oscillator by detecting a frequency of the pulse signal.

2. The aerosol-generating device of claim 1, wherein the controller is further configured to trigger an interrupt process of the controller when the pulse signal is received.

3. An aerosol-generating device according to claim 1 or 2, wherein the controller is configured to derive the frequency of the pulsed signal in dependence on the time interval of a transition edge in the pulsed signal.

4. The aerosol-generating device of claim 3, wherein the transition edge comprises a rising edge and a falling edge; the controller is configured to acquire the frequency of the pulse signal according to the interval time of adjacent rising edges or falling edges of the pulse signal.

5. The aerosol-generating device of claim 3, wherein the controller comprises a capture compare register to capture a transition edge of the pulse signal.

6. The aerosol-generating device of claim 5, wherein the controller comprises a counter to count a number of transition edges captured by the capture compare register.

7. The aerosol-generating device of claim 5, wherein the controller comprises a timer to store a time at which the capture compare register captures a transition edge.

8. An aerosol-generating device according to claim 1 or 2, wherein the controller is further configured to adjust the oscillation frequency of the LC oscillator such that the oscillation frequency of the LC oscillator remains the same or substantially close to a preset frequency.

9. A method of controlling an aerosol-generating device, the aerosol-generating device comprising:

a susceptor configured to be penetrated by a varying magnetic field to generate heat to heat an aerosol-generating article;

an LC oscillator having an inductor coil configured to direct a varying current through the inductor coil to drive the inductor coil to generate a varying magnetic field;

characterized in that the method comprises:

comparing the oscillation voltage of the LC oscillator with a preset value, and outputting a pulse signal with the same frequency as the oscillation voltage according to a comparison result;

and receiving the pulse signal, and acquiring the oscillation frequency of the LC oscillator by calculating the frequency of the pulse signal.

10. The method of controlling an aerosol-generating device according to claim 9, further comprising:

and adjusting the oscillation frequency of the LC oscillator so that the oscillation frequency of the LC oscillator is the same as or basically close to the preset frequency.

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