Dry burning prevention control method and circuit of electronic cigarette

Abstract

The invention discloses an anti-dry-burning control method of an electronic cigarette and a circuit thereof. The control method comprises the following steps: S1, setting a tobacco juice residual amount threshold value L1 near dry burning, and setting a resistance value amplification first threshold value R1; s2, when the starting switch is switched on and the heating resistor is powered off, the tobacco juice residual amount detection unit detects the tobacco juice residual amount real-time value L in real time; s3, after the starting switch is switched on and before the heating resistor is powered on, a resistance value detection unit detects the heating resistor in real time to obtain a real-time resistance value R, and the microprocessor sets the real-time resistance value R obtained in the current period as an initial resistance value R0; s4, when the heating resistor is powered on and powered off, the microprocessor obtains the real-time change amplitude value of the resistance value as R-R0; and S5, when the microprocessor analyzes and judges that L is smaller than or equal to L1 and R-R0 is larger than or equal to R1, output is cut off immediately, power is forbidden to be supplied to the heating resistor again, and dry burning prevention protection is facilitated. The method has the advantages that whether the electronic cigarette reaches the dry burning state or not can be accurately analyzed and judged, dry burning protection is carried out, and a user is prevented from inhaling electronic cigarette smoke with scorched smell.

Description

Technical Field

[0001] The present invention relates to the technical field of dry-burning prevention of electronic cigarettes. More specifically, the present invention relates to a dry-burning prevention control method for an electronic cigarette. Background Art

[0002] An electronic cigarette generally includes a battery assembly and an atomizer. The atomizer includes an atomizing device. After the heating resistor in the atomizing device is energized, it generates heat, and the e-liquid of the electronic cigarette in contact with the heating resistor is heated and atomized to form a steam-like smoke. The smoke flows through the smoke channel in the atomizer to the mouthpiece of the atomizer for the user to inhale.

[0003] During the actual use of an electronic cigarette, it may occur that when the e-liquid is exhausted or the e-liquid does not make good contact with the heating resistor, resulting in no e-liquid around the heating resistor when it is heating, and only the heating resistor is in a "dry-burning" situation, which is likely to damage the electronic cigarette.

[0004] Existing electronic cigarettes generally include directly detecting the content of the e-liquid or detecting the resistance value of the heating resistor, that is, detecting the working temperature of the heating resistor to determine whether the electronic cigarette is in a "dry-burning" state, and then performing power-off protection. The existing dry-burning prevention protection methods for electronic cigarettes generally detect the absolute value of the resistance of the heating resistor, and when it is determined that its resistance value reaches the dry-burning protection set value, the battery assembly cuts off the power supply to the heating resistor for dry-burning prevention protection, or when it is determined that the rate of change of its resistance value within a certain time reaches the dry-burning protection set value, the battery assembly cuts off the power supply to the heating resistor for dry-burning prevention protection.

[0005] However, directly detecting the content of the e-liquid is difficult to accurately detect due to the shaking of the atomizer causing the liquid level of the e-liquid to keep changing, and directly detecting the working temperature of the heating resistor may also cause a temporary lack of e-liquid around the heating resistor during heating due to the poor contact between the e-liquid and the heating resistor, resulting in a short-term dry-burning. Therefore, these methods will cause inaccurate dry-burning judgments and result in dry-burning protection, making the electronic cigarette unable to continue to be used when there is still e-liquid, and there is no circuit that can accurately, real-time and conveniently detect and protect whether the atomizer has a real dry-burning. Summary of the Invention

[0006] The present invention provides a dry-burning prevention control method for an electronic cigarette and its circuit to overcome the above technical deficiencies.

[0007] The technical solution of the present invention is realized as follows: A dry-burning prevention control method for an electronic cigarette includes the following steps:

[0008] S1. In the circuit of the electronic cigarette, a heating resistor, a liquid level detection unit, a resistance value detection unit, a microprocessor, a start switch, and a power adjustment unit are electrically connected. A liquid level threshold L1 near dry burning is set, and a first threshold R1 for the increase in the resistance value of the heating resistor during dry burning is set.

[0009] S2. During each puff, from when the start switch is turned on until the heating resistor is powered off, the liquid level detection unit continuously detects the real-time liquid level value L and sends it to the microprocessor.

[0010] S3. During each puff, from when the start switch is turned on until the heating resistor is powered on, the resistance value detection unit continuously detects the real-time resistance value R of the heating resistor and sends it to the microprocessor, and the microprocessor sets the real-time resistance value R obtained during this period as the initial resistance value R0.

[0011] S4. During each puff, from when the heating resistor is powered on until the heating resistor is powered off, the resistance value detection unit continuously detects the real-time resistance value R of the heating resistor and sends it to the microprocessor, and the microprocessor subtracts the real-time resistance value R obtained during this period from the initial resistance value R0 to get the real-time change amplitude value of the resistance value as R - R0.

[0012] S5. When the microprocessor analyzes and determines that L ≤ L1 and R - R0 ≥ R1, the microprocessor controls the power adjustment unit to immediately cut off the output and prohibit it from supplying power to the heating resistor again for dry-burning protection.

[0013] Preferably, step S1 further includes: setting a second threshold R2 for the increase in the resistance value of the heating resistor that may cause dry burning, and setting R2 > R1; and further including step S6: when the microprocessor analyzes and determines that L > L1 and R - R0 ≥ R2, the microprocessor controls the power adjustment unit to temporarily cut off the power supply to the heating resistor for temporary dry-burning protection.

[0014] Preferably, step S1 further includes: setting the power adjustment unit to constant power output, the liquid level detection unit includes a timer, and equivalently replacing the liquid level threshold L1 with a duration threshold T1 for the heating resistor to work; step S2 further includes: equivalently replacing the real-time liquid level value L with a real-time duration threshold T for the heating resistor to work; step S5 further includes: equivalently replacing the microprocessor's analysis and determination of L ≤ L1 with the analysis and determination of T ≤ T1.

[0015] Preferably, step S1 further includes: setting the power adjustment unit to a constant power output, the e-liquid remaining amount detection unit includes a timer, and equivalently replacing the e-liquid remaining amount threshold L1 with the working duration remaining threshold T1 of the heating resistor; step S2 further includes: equivalently replacing the real-time value L of the e-liquid remaining amount with the real-time value T of the working duration remaining of the heating resistor; step S5 further includes: equivalently replacing the microprocessor analyzing and determining L ≤ L1 with analyzing and determining T ≤ T1; step S6 further includes: equivalently replacing the microprocessor analyzing and determining L > L1 with analyzing and determining T > T1.

[0016] Preferably, step S1 further includes: setting a time interval threshold t1; step S2 further includes: the microprocessor obtaining the time interval t between the end of the previous puff and the start of the current puff; step S3 further includes: when the microprocessor analyzes and determines that t ≤ t1, replacing the initial resistance value R0 obtained during the current puff with the initial resistance value R0 obtained during the previous puff.

[0017] Preferably, in step S3, the microprocessor takes the average value of the multiple real-time resistance values R obtained during this period and sets this average value as the initial resistance value R0.

[0018] Preferably, in step S3, the microprocessor sets the lowest value among the multiple real-time resistance values R obtained during this period as the initial resistance value R0.

[0019] Preferably, in step S3, the microprocessor sets the first value or the last value among the multiple real-time resistance values R obtained during this period as the initial resistance value R0.

[0020] Preferably, the value range of L1 is set to (0.5% - 2%)L0, where L0 is the total e-liquid volume value, and the value range of R1 is set to 0.05Ω - 0.9Ω.

[0021] Preferably, the value range of L1 is set to (0.5% - 2%)L0, where L0 is the total e-liquid volume value, the value range of R1 is set to 0.05Ω - 0.9Ω, and the value range of R2 is set to 0.09Ω - 1.0Ω.

[0022] Preferably, the value range of L0 is set to 1ml - 10ml.

[0023] Preferably, the value range of T1 is set to (0.5% - 2%)T0, where T0 is the total working duration of the heating resistor, and the value range of R1 is set to 0.05Ω - 0.9Ω.

[0024] Preferably, the value range of T1 is set to (0.5%-2%)T0, where T0 is the total working duration of the heating resistor. The value range of R1 is set to 0.05 Ω - 0.9 Ω, and the value range of R2 is set to 0.09 Ω - 1.0 Ω.

[0025] Preferably, the value range of T0 is set to 400 seconds - 4000 seconds.

[0026] Preferably, the value range of t1 is set to 2 - 4 seconds.

[0027] Another technical solution of the present invention is implemented as follows: A circuit for implementing the dry-burning prevention control method of an electronic cigarette, including an electrically connected battery, a power regulation unit, a microprocessor, a start switch, a sampling reference resistor, a resistance value detection unit, a liquid level detection unit for the e-liquid, and an e-liquid data storage module. When the start switch is turned on or off, the microprocessor controls the power regulation unit to output power to the heating resistor or turn off the output. The resistance value detection unit is used to detect the resistance value R of the heating resistor in real time and transmit it to the microprocessor. The liquid level detection unit for the e-liquid is used to detect the real-time value L of the remaining e-liquid in the atomizer in real time and transmit it to the microprocessor. The e-liquid data storage module is used to store the initial resistance value R0, the resistance value R detected in real time, the real-time value L of the remaining e-liquid, and some initially set thresholds and data.

[0028] Preferably, it further includes a timer, which is used to detect and calculate the time interval t between the turn-off of the power supply of the heating resistor at the end of the previous puff and the turn-on of the start switch at the start of the next puff.

[0029] Another technical solution of the present invention is implemented as follows: A circuit for implementing the dry-burning prevention control method of an electronic cigarette, including an electrically connected battery, a power regulation unit, a microprocessor, a start switch, a sampling reference resistor, a resistance value detection unit, a liquid level detection unit for the e-liquid, and an e-liquid data storage module. When the start switch is turned on or off, the microprocessor controls the power regulation unit to output power to the heating resistor or turn off the output. The resistance value detection unit is used to detect the resistance value R of the heating resistor in real time and transmit it to the microprocessor. The liquid level detection unit for the e-liquid includes a timer, which is used to accumulate the working duration Ta of the heating resistor in real time and transmit it to the microprocessor. The e-liquid data storage module is used to store the initial resistance value R0, the resistance value R detected in real time, the real-time value T of the remaining working duration of the heating resistor, and some initially set thresholds and data.

[0030] Preferably, the timer is further used to detect and calculate the time interval t between the turn-off of the power supply of the heating resistor at the end of the previous puff and the turn-on of the start switch at the start of the next puff.

[0031] Preferably, the atomizer circuit further includes an anti-counterfeiting chip, which includes an anti-counterfeiting data storage module and an e-liquid data storage module.

[0032] The beneficial effect of the dry-burning prevention control method for the electronic cigarette of the present invention is that by simultaneously detecting the remaining amount of e-liquid in the electronic cigarette and the amplitude value of the resistance change during each puff, it can accurately analyze and judge whether the electronic cigarette reaches the dry-burning state or the temporary dry-burning state, and then respectively perform permanent dry-burning protection and temporary dry-burning protection, avoiding users from inhaling the smoky electronic cigarette with a burnt smell and enhancing the good user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is the dry-burning prevention circuit of the electronic cigarette of the present invention Figure 1 ;

[0034] Figure 2 is the dry-burning prevention circuit of the electronic cigarette of the present invention Figure 2 ;

[0035] Figure 3 is the dry-burning prevention circuit of the electronic cigarette of the present invention Figure 3 ;

[0036] Figure 4 is the graph of the resistance value change of the heating resistor when the electronic cigarette of the present invention is working. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not used to limit the present invention.

[0038] The electronic cigarette of the present invention is composed of a battery assembly and an atomizer. The battery assembly provides power to the atomizer. Among them, the battery assembly is detachably or non-detachably connected to the atomizer. In the case of detachable connection, the atomizer can be replaced after its e-liquid is consumed, and the battery assembly can be reused multiple times. In the case of non-detachable connection, the atomizer and the battery assembly are fixedly connected, and the atomizer cannot be replaced after its e-liquid is consumed, that is, the electronic cigarette is a disposable electronic cigarette.

[0039] The meanings of the following letters and symbols in the present invention are as follows:

[0040] L0 = total e-liquid amount value, L1 = e-liquid remaining amount threshold, L = e-liquid remaining amount real-time value.

[0041] T0 = total duration, T1 = duration remaining amount threshold, Ta = elapsed working duration, T = duration remaining amount real-time value.

[0042] t1 = time interval threshold, t = time interval between the end of the previous puff and the start of the next puff.

[0043] R0 = initial resistance value, R1 = first threshold value of resistance increase, R2 = second threshold value of resistance increase, R = real-time resistance value.

[0044] Embodiment 1

[0045] As Figure 1 shown, the circuit for implementing the anti-dry-burning control method of the electronic cigarette in this embodiment includes a battery component circuit and an atomizer circuit. Among them, the atomizer circuit includes a heating resistor and a liquid level detection unit for the remaining liquid. The battery component circuit includes a battery, a power regulation unit, a microprocessor, a liquid data storage module, a start switch, a sampling reference resistor, and a resistance detection unit that are electrically connected. Among them, the microprocessor includes a liquid information calculation module, a dry-burning judgment module, and a resistance change judgment module, and these modules are parts with specific functions in the integrated circuit components; the liquid level detection unit for the remaining liquid, the liquid data storage module, the resistance detection unit, the power regulation unit, and the start switch are respectively communicatively connected to the microprocessor. After the start switch is turned on, the microprocessor controls the power regulation unit to output power to the heating resistor, and the heating resistor is energized to generate heat, and the electronic cigarette starts to work. When the start switch is turned off, the microprocessor controls the power regulation unit to cut off the output to the heating resistor, and the electronic cigarette enters the standby state. In the circuit configuration of the electronic cigarette of the present invention, when the start switch is turned on, the power regulation unit does not immediately output power to the heating resistor, but there is a delay, and the delay time can usually be designed to be 10 - 100 milliseconds. In this embodiment, the start switch is an airflow sensor. Each time the user takes a puff, an inhalation airflow is generated inside the electronic cigarette, and the airflow sensor is triggered by sensing the inhalation airflow, and the start switch is turned on. When the user stops puffing, there is no inhalation airflow, so the airflow sensor cannot sense the airflow and is turned off. In other embodiments, the start switch can be a manual button switch, or a microphone or a pressure sensor, etc. When the airflow sensor or the pressure sensor or the microphone detects the airflow or negative pressure generated by the user's smoking in the air path of the electronic cigarette, it can be triggered to control the power regulation unit to turn on the power supply of the heating resistor, and turn it off when the user stops puffing. The manual button switch is turned on when manually pressed and turned off when pressed again. The resistance detection unit can detect the resistance value of the heating resistor in real time and transmit it to the microprocessor. The liquid data storage module can be used to store data such as the resistance value and duration detected in real time, as well as some preset threshold values and data. The liquid level detection unit for the remaining liquid is used to detect the remaining stock of the liquid in the atomizer in real time, and the liquid level detection unit for the remaining liquid is a liquid level sensor for detecting the remaining liquid level in real time. The heating resistor of the electronic cigarette of the present invention is a positive temperature coefficient thermistor, that is, the higher the temperature, the greater its resistance value. In other embodiments, the liquid data storage module can also be arranged inside the microprocessor without being set up separately.

[0046] Embodiment 2

[0047] As Figure 2 shown, the circuit for implementing the dry - burn prevention control method of the electronic cigarette in this embodiment, on the basis of the previous embodiment, the liquid level detection unit is not arranged in the atomizer circuit, but in the battery module circuit. The liquid level detection unit includes a timer, and this timer belongs to the detection unit that can detect and calculate the liquid level of the e - liquid equally. Since there is a certain amount of e - liquid stored in the atomizer, under the condition of the same power, the heating resistor will consume it after working for a certain period of time. There is a corresponding relationship between the total value of the e - liquid volume L0 and the total duration T0 during which the e - liquid is consumed, that is, the total working duration of the heating resistor. The real - time value L of the remaining e - liquid volume also corresponds to the real - time value T of the remaining working duration of the heating resistor. Therefore, detecting the remaining e - liquid volume can be equivalently replaced by detecting the remaining working duration of the heating resistor. That is, the liquid level detection unit can be specifically designed as a timer for detecting the working duration of the heating resistor. In addition, every time the user takes a puff, the start switch is turned on once, and then the heating resistor is powered on once. The duration of the power - on is the duration of each puff, that is, the working duration of the start switch corresponds to the working duration of the heating resistor. Therefore, the timer can accumulate the working time of the start switch, that is, accumulate the already - worked duration Ta of the start switch (corresponding to the already - worked duration of the heating resistor) and send it to the micro - processor. If the set total working duration of the heating resistor is T0 (which can be converted into the total value of the e - liquid volume L0), then the micro - processor can calculate the real - time value T of the remaining working duration of the heating resistor: T = T0 - Ta. The real - time value T of the remaining working duration of the heating resistor is equivalent to the real - time value L of the remaining e - liquid volume. The timer can also be used to detect and calculate the time interval t between the moment when the power supply of the heating resistor is turned off (that is, the power - regulation unit is turned off) at the end of the previous puff and the moment when the start switch is turned on at the beginning of the next puff.

[0048] Embodiment 3

[0049] As Figure 3 shown, the circuit for implementing the dry - burn prevention control method of the electronic cigarette in this embodiment, on the basis of the previous embodiment, when the electronic cigarette battery module and the atomizer are detachably connected, the atomizer circuit further includes an anti - counterfeiting chip. The anti - counterfeiting chip is originally used for anti - counterfeiting functions. Because it also has a storage module that can be utilized, the e - liquid data storage module can be transferred to the storage module in the anti - counterfeiting chip. That is, the anti - counterfeiting chip can include an anti - counterfeiting data storage module and an e - liquid data storage module, and also includes a data backup module and a data reading and writing processing module. The e - liquid data storage module can store e - liquid level data, setting data, and can also store data such as the already - worked duration data, the available working duration data, the real - time value of the remaining duration, and setting data of the heating resistor representing the e - liquid level. The anti - counterfeiting chip in this embodiment uses an anti - counterfeiting chip with the model number XJX001.

[0050] The existing dry-burning prevention control methods for electronic cigarettes generally detect the absolute value of the resistance of the heating resistor, and when it is determined that the resistance value reaches the dry-burning protection setting value, the battery assembly cuts off the power supply to the heating resistor for dry-burning protection, or when it is determined that the rate of change of the resistance value within a certain period of time reaches the dry-burning protection setting value, the battery assembly cuts off the power supply to the heating resistor for dry-burning protection.

[0051] The dry-burning prevention control method of the present invention includes temporary dry-burning protection when the remaining amount of e-liquid is greater than the e-liquid remaining amount threshold L1 at near dry-burning and permanent dry-burning protection when the remaining amount of e-liquid is lower than or equal to the e-liquid remaining amount threshold L1 at near dry-burning. In both cases, it is also necessary to determine whether the change in the heating resistor R within each puff by the user reaches a certain increase. If the set resistance value increase is reached, it is determined as dry-burning, and dry-burning protection or temporary dry-burning protection is performed.

[0052] Embodiment 4

[0053] As Figure 4 shown, on the T time axis, t11 - t13, t21 - t23, t31 - t33 are the times for each puff, the time points of t11, t21, t31 are the time points when the start switch is turned on, the time points of t12, t22, t32 are the time points when the heating resistor is powered on, and the time points of t13, t23, t33 are the time points when the heating resistor is powered off.

[0054] In this embodiment, a dry-burning prevention control method for an electronic cigarette is provided, including the following steps:

[0055] S1. In the circuit of the electronic cigarette, a heating resistor, an e-liquid remaining amount detection unit, a resistance value detection unit, a microprocessor, an e-liquid data storage module, a start switch, and a power adjustment unit are electrically connected. In the e-liquid data storage module, the e-liquid remaining amount threshold at near dry-burning is set to L1 = 0.1 ml, and the first threshold for the resistance value increase of the heating resistor when dry-burning occurs is set to R1 = 0.12 Ω; another e-liquid total amount value L0 = 10 ml is set.

[0056] S2. During each puff, from when the start switch is turned on until the heating resistor is powered off (such as Figure 4 the time periods of t11 - t13, t21 - t23, t31 - t33 shown), the e-liquid remaining amount detection unit detects the real-time e-liquid remaining amount value L in real time and sends it to the microprocessor.

[0057] S3. During each puff, from when the start switch is turned on until before the heating resistor is powered on (such as Figure 4 the time periods of t11 - t12, t21 - t22, t31 - t32 shown), the resistance value detection unit detects the real-time resistance value R of the heating resistor in real time and sends it to the microprocessor, and the microprocessor sets the real-time resistance value R obtained during this period as the initial resistance value R0.

[0058] S4, during each puff, the heating resistor is powered on and powered off (such as Figure 4 The resistance detection unit detects the heating resistor in real time to obtain the real-time resistance R and sends it to the microprocessor. The microprocessor subtracts the real-time resistance R obtained in this period from the initial resistance R0 to obtain the real-time resistance change amplitude R-R0.

[0059] S5. When the microprocessor analyzes and determines that L≤L1 and R-R0≥R1, the microprocessor controls the power regulation unit to immediately shut down the output and prohibit it from supplying power to the heating resistor again to perform anti-dry burning protection.

[0060] In the above step S3, due to the circuit configuration of the present invention, when the start switch is turned on, the power adjustment unit does not immediately output power to the heating resistor, but there is some delay, and the delay time can be designed to be 20 milliseconds. That is, during each puff, after the start switch is turned on and before the heating resistor is powered on, the resistance detection unit detects the heating resistor in real time to obtain one or more real-time resistance values ​​R and sends them to the microprocessor, and the microprocessor sets the real-time resistance value R obtained during this period as the initial resistance value R0. The preferred solution used in this embodiment is that the microprocessor takes the lowest value of the multiple real-time resistance values ​​R obtained during this period as the initial resistance value R0. In other embodiments, the microprocessor can also take the average value of the multiple real-time resistance values ​​R obtained during this period and set the average value as the initial resistance value R0, or take the first value or the last value of the multiple real-time resistance values ​​R obtained during this period as the initial resistance value R0. The initial resistance value R0 is set according to the resistance value detected in real time during each puff, so the initial resistance value of each puff is not a fixed resistance value, but a resistance value that changes according to the actual. The initial resistance value R0 changes according to the actual situation, which helps to compare the real-time resistance value detected when the heating resistor is powered on to obtain the resistance change amplitude value R-R0 within each puff range, which can truly reflect the temperature increase within each puff range, so that the microprocessor can accurately determine whether dry burning occurs. It is understandable that since the initial resistance value R0 of each puff will change with the temperature increase of the heating resistor when the user takes each puff, the resistance amplitude change R-R0 of each puff also changes. If R0 is kept unchanged, the resistance amplitude change R-R0 cannot truly reflect the actual change of resistance during each puff, which may lead to the misjudgment of dry burning. Therefore, setting the real-time resistance value detected at the beginning of each puff as the initial resistance value R0 can accurately reflect whether dry burning actually occurs.

[0061] In the above steps, when the microprocessor reads and determines that the real-time value L of the remaining e-liquid is L ≤ L1, and reads and determines that the resistance change amplitude value R - R0 of the real-time resistance R during each puff of the user relative to the initial resistance R0 is R - R0 ≥ R1, that is, at this time, the e-liquid in the atomizer is nearly insufficient, and the resistance change amplitude value during each puff has exceeded the set value. Therefore, the microprocessor determines that the heating resistor has a real dry burn and controls the power adjustment unit to turn off the output and prohibits it from supplying power to the heating resistor again. In this way, it can accurately determine that the e-liquid in the atomizer is close to the minimum limit, and avoid continuously supplying power to the atomizer with almost no e-liquid, preventing the user from inhaling smoky with a burnt smell and causing an unpleasant user experience.

[0062] Embodiment 5

[0063] As Figure 4 shown, on the T time axis, t11 - t13, t21 - t23, t31 - t33 are the times of each puff. The time points of t11, t21, t31 are the time points when the start switch is turned on. The time points of t12, t22, t32 are the time points when the heating resistor is powered on. The time points of t13, t23, t33 are the time points when the heating resistor is powered off.

[0064] Based on Embodiment 4, a dry-burning prevention control method for an electronic cigarette in this embodiment includes the following steps:

[0065] S1. In the circuit of the electronic cigarette, set a heating resistor, an e-liquid remaining amount detection unit, a resistance detection unit, a microprocessor, an e-liquid data storage module, a start switch, and a power adjustment unit that are electrically connected. In the e-liquid data storage module, set the e-liquid remaining amount threshold L1 = 0.1 ml when approaching dry burn, set the first threshold of the resistance increase of the heating resistor when dry burn occurs as R1 = 0.12 Ω, set the second threshold of the resistance increase of the heating resistor that may cause dry burn as R2 = 0.17 Ω, and another set the total e-liquid amount value L0 = 10 ml.

[0066] S2. During each puff, from when the start switch is turned on to when the heating resistor is powered off (such as Figure 4 shown in the time periods of t11 - t13, t21 - t23, t31 - t33), the e-liquid remaining amount detection unit detects the real-time value L of the remaining e-liquid in real time and sends it to the microprocessor.

[0067] S3. During each puff, from when the start switch is turned on to before the heating resistor is powered on (such as Figure 4 shown in the time periods of t11 - t12, t21 - t22, t31 - t32), the resistance detection unit detects the real-time resistance R of the heating resistor in real time and sends it to the microprocessor. The microprocessor sets the real-time resistance R obtained during this time period as the initial resistance R0.

[0068] S4. During each puff, from the time when the heating resistor is powered on to the time when it is powered off (such as the time periods t12 - t13, t22 - t23, t32 - t33 shown in Figure 4 ), the resistance value detection unit continuously detects the resistance value of the heating resistor to obtain a real-time resistance value R and sends it to the microprocessor. The microprocessor subtracts the initial resistance value R0 from the real-time resistance value R obtained during this period to get the real-time change amplitude value of the resistance value as R - R0.

[0069] S5. When the microprocessor analyzes and determines that L ≤ L1 and R - R0 ≥ R1, the microprocessor controls the power adjustment unit to immediately turn off the output and prohibits it from supplying power to the heating resistor again for dry-burning protection.

[0070] S6. When the microprocessor analyzes and determines that L > L1 and R - R0 ≥ R2, the microprocessor controls the power adjustment unit to temporarily turn off the power supply to the heating resistor for temporary dry-burning protection.

[0071] In the above step S3, due to the circuit configuration of the present invention, when the start switch is turned on, the power adjustment unit does not immediately output power to the heating resistor but has a certain delay, and the delay time can be designed to be 20 milliseconds. That is, during each puff, after the start switch is turned on and before the heating resistor is powered on, the resistance value detection unit continuously detects the heating resistor to obtain one or more real-time resistance values R and sends them to the microprocessor. The microprocessor sets the real-time resistance value R obtained during this period as the initial resistance value R0. In a preferred solution of this embodiment, the microprocessor takes the lowest value among the multiple real-time resistance values R obtained during this period and sets it as the initial resistance value R0. In other embodiments, the microprocessor can also take the average value of the multiple real-time resistance values R obtained during this period and set this average value as the initial resistance value R0, or take the first value or the last value among the multiple real-time resistance values R obtained during this period and set it as the initial resistance value R0. The initial resistance value R0 is set according to the real-time detected resistance value during each puff, so the initial resistance value for each puff is not a fixed value but varies according to the actual resistance value. The variation of the initial resistance value R0 according to the actual situation helps to compare the real-time resistance value detected when the heating resistor is powered on with it to obtain the resistance value change amplitude value R - R0 within the range of each puff, which can truly reflect the temperature increase amplitude within the range of each puff, so that the microprocessor can accurately determine whether dry-burning occurs. It can be understood that since the user's initial resistance value R0 for each puff changes as the temperature of the heating resistor increases during each puff, the resistance value amplitude change R - R0 for each puff also changes. If R0 remains unchanged, the resistance value amplitude change R - R0 cannot truly reflect the actual change of the resistance value during each puff, which may lead to misjudgment of dry-burning. Therefore, setting the real-time resistance value detected at the beginning of each puff as the initial resistance value R0 can accurately reflect whether dry-burning actually occurs.

[0072] In the above steps, if the microprocessor reads and determines that the real-time value L of the e-liquid remaining amount satisfies L ≤ L1, and reads and determines that the resistance change amplitude value R - R0 of the real-time resistance R during each puff of the user relative to the initial resistance R0 is greater than or equal to R1, that is, at this time, the e-liquid in the atomizer is nearly insufficient, and the resistance change amplitude value during each puff has exceeded the set value. Therefore, the microprocessor determines that the heating resistor has a real dry burn and controls the power adjustment unit to turn off the output, and prohibits it from supplying power to the heating resistor again. In this way, it can accurately determine that the e-liquid in the atomizer is close to the minimum limit, and avoid continuously supplying power to the atomizer with nearly no e-liquid, preventing the user from inhaling smoky fumes with a burnt smell and causing an unpleasant use experience.

[0073] Meanwhile, if the microprocessor reads and determines that the e-liquid remaining amount value L > L1, and reads and determines that the resistance change amplitude value R - R0 ≥ R2, that is, at this time, the e-liquid in the atomizer is still sufficient, but due to the different placement angles of the atomizer, the liquid supply is not timely or sufficient, resulting in a temporary lack of e-liquid around the heating resistor and causing a temporary dry burn. Therefore, the microprocessor determines that the heating resistor may have a temporary dry burn and controls the power adjustment unit to temporarily turn off the output, making the heating resistor stop working. If the liquid supply around the heating resistor can be quickly restored, when the user continues to puff and the detected resistance change amplitude value R - R0 < R2, the microprocessor controls the power adjustment unit to restore power supply to the heating resistor, and the electronic cigarette can continue to work. In this case, the microprocessor can accurately determine the temporary dry burn of the heating resistor and perform temporary dry burn protection, also avoiding the user from inhaling smoky fumes with a burnt smell and causing an unpleasant use experience.

[0074] Embodiment Six

[0075] As Figure 4 shown, on the T time axis, t11 - t13, t21 - t23, t31 - t33 are the times of each puff. The time points of t11, t21, t31 are the time points when the start switch is turned on. The time points of t12, t22, t32 are the time points when the heating resistor is powered on. The time points of t13, t23, t33 are the time points when the heating resistor is powered off.

[0076] Based on Embodiment Four, a method for preventing dry burn control of an electronic cigarette in this embodiment includes the following steps:

[0077] S1. In the circuit of an electronic cigarette, a heating resistor, a liquid level detection unit, a resistance detection unit, a microprocessor, a liquid data storage module, a start switch, and a power adjustment unit are electrically connected. The liquid level detection unit includes a timer. The power adjustment unit is set to output at a constant power. In the liquid data storage module, a remaining working time threshold T1 = 35 seconds for the heating resistor when approaching dry burning is set, and a first threshold for the resistance increase of the heating resistor during dry burning is set as R1 = 0.12 Ω. Additionally, a total working time T0 = 3500 seconds for the heating resistor is set.

[0078] S2. During each puff, from when the start switch is turned on until the heating resistor is powered off (such as the time periods t11 - t13, t21 - t23, t31 - t33 shown), the timer continuously detects the real-time remaining working time value T of the heating resistor and sends it to the microprocessor. Figure 4 shown in t11 - t13, t21 - t23, t31 - t33 time periods), the timer continuously detects the real-time remaining working time value T of the heating resistor and sends it to the microprocessor.

[0079] S3. During each puff, from when the start switch is turned on until before the heating resistor is powered on (such as the time periods t11 - t12, t21 - t22, t31 - t32 shown), the resistance detection unit continuously detects the real-time resistance R of the heating resistor and sends it to the microprocessor. The microprocessor sets the real-time resistance R obtained during this time period as the initial resistance R0. Figure 4 shown in t11 - t12, t21 - t22, t31 - t32 time periods), the resistance detection unit continuously detects the real-time resistance R of the heating resistor and sends it to the microprocessor. The microprocessor sets the real-time resistance R obtained during this time period as the initial resistance R0.

[0080] S4. During each puff, from when the heating resistor is powered on until it is powered off (such as the time periods t12 - t13, t22 - t23, t32 - t33 shown), the resistance detection unit continuously detects the real-time resistance R of the heating resistor and sends it to the microprocessor. The microprocessor subtracts the real-time resistance R obtained during this time period from the initial resistance R0 to get the real-time change amplitude value of the resistance as R - R0. Figure 4 shown in t12 - t13, t22 - t23, t32 - t33 time periods), the resistance detection unit continuously detects the real-time resistance R of the heating resistor and sends it to the microprocessor. The microprocessor subtracts the real-time resistance R obtained during this time period from the initial resistance R0 to get the real-time change amplitude value of the resistance as R - R0.

[0081] S5. When the microprocessor analyzes and determines that T ≤ T1 and R - R0 ≥ R1, the microprocessor controls the power adjustment unit to immediately turn off the output and prohibits it from supplying power to the heating resistor again for dry-burning protection.

[0082] In the above steps, the e-liquid remaining amount detection unit includes a timer, and the detection of the e-liquid remaining amount is achieved by the method of timing with the timer. This timer belongs to the detection unit that can detect and calculate the e-liquid remaining amount equally. Since there is a certain amount of e-liquid stored in the atomizer, under the condition of the same power, the heating resistor can consume it after working for a certain period of time. There is a corresponding relationship between the total e-liquid amount value L0 and the total duration T0 during which the e-liquid is consumed, that is, the total working duration of the heating resistor. The real-time value L of the e-liquid remaining amount and the real-time value T of the remaining working duration of the heating resistor are also corresponding. Therefore, the detection of the e-liquid remaining amount can be equivalently replaced by detecting the remaining working duration of the heating resistor. That is, the e-liquid remaining amount detection unit can be specifically designed as a timer for detecting the working duration of the heating resistor. In addition, every time the user takes a puff of smoke, the start switch is turned on once, and then the heating resistor is powered on once. The duration of the power-on is the duration of each puff of smoke, that is, the working duration of the start switch corresponds to the working duration of the heating resistor. Therefore, the timer can accumulate the working time of the start switch, that is, accumulate the already working duration Ta of the start switch (corresponding to the already working duration of the heating resistor) and send it to the microprocessor. If the set total working duration of the heating resistor is T0 (which can be converted into the total e-liquid amount value L0), the microprocessor can calculate the real-time value T of the remaining working duration of the heating resistor as T = T0 - Ta. The real-time value T of the remaining working duration of the heating resistor is equivalent to the real-time value L of the e-liquid remaining amount.

[0083] When the microprocessor reads and judges that the real-time value T of the remaining duration is less than or equal to T1, and reads and judges that the resistance change amplitude value R - R0 of the real-time resistance R during each puff of the user relative to the initial resistance R0 is greater than or equal to R1, that is, at this time, because the e-liquid in the atomizer is almost insufficient, and the resistance change amplitude value during each puff has exceeded the set value, the microprocessor judges that the heating resistor has a real dry burn and controls the power adjustment unit to turn off the output and prohibits it from supplying power to the heating resistor again. In this way, it can accurately judge that the e-liquid in the atomizer is close to the minimum limit, and avoid continuing to supply power to the atomizer that is almost out of e-liquid, and prevent the user from inhaling smoky with a burnt smell and causing an unpleasant use experience.

[0084] Embodiment Seven

[0085] As Figure 4 shown, on the T time axis, t11 - t13, t21 - t23, t31 - t33 are the times of each puff of smoke. The time points of t11, t21, t31 are the time points when the start switch is turned on. The time points of t12, t22, t32 are the time points when the heating resistor is powered on. The time points of t13, t23, t33 are the time points when the heating resistor is powered off.

[0086] Based on Embodiment Five, a dry-burning prevention control method for an electronic cigarette in this embodiment includes the following steps:

[0087] S1. In the circuit of an electronic cigarette, a heating resistor, a liquid level detection unit, a resistance detection unit, a microprocessor, a liquid data storage module, a start switch, and a power adjustment unit are electrically connected. The liquid level detection unit includes a timer. The power adjustment unit is set to output at a constant power. In the liquid data storage module, a remaining working time threshold T1 = 35 seconds for the heating resistor when approaching dry burning is set, a first threshold R1 = 0.12 Ω for the resistance increase of the heating resistor when dry burning occurs is set, a second threshold R2 = 0.17 Ω for the resistance increase of the heating resistor when possible dry burning may occur is set, and a total working time T0 = 3500 seconds for the heating resistor is set.

[0088] S2. During each puff, from when the start switch is turned on until the heating resistor is powered off (such as the time periods t11 - t13, t21 - t23, t31 - t33 shown), the timer continuously detects the real - time remaining working time value T of the heating resistor and sends it to the microprocessor. Figure 4 shown t11 - t13, t21 - t23, t31 - t33 time periods), the timer continuously detects the real - time remaining working time value T of the heating resistor and sends it to the microprocessor.

[0089] S3. During each puff, from when the start switch is turned on until before the heating resistor is powered on (such as the time periods t11 - t12, t21 - t22, t31 - t32 shown), the resistance detection unit continuously detects the real - time resistance R of the heating resistor and sends it to the microprocessor, and the microprocessor sets the real - time resistance R obtained during this time period as the initial resistance R0. Figure 4 shown t11 - t12, t21 - t22, t31 - t32 time periods), the resistance detection unit continuously detects the real - time resistance R of the heating resistor and sends it to the microprocessor, and the microprocessor sets the real - time resistance R obtained during this time period as the initial resistance R0.

[0090] S4. During each puff, from when the heating resistor is powered on until it is powered off (such as the time periods t12 - t13, t22 - t23, t32 - t33 shown), the resistance detection unit continuously detects the real - time resistance R of the heating resistor and sends it to the microprocessor, and the microprocessor subtracts the real - time resistance R obtained during this time period from the initial resistance R0 to get the real - time change amplitude value of the resistance as R - R0. Figure 4 shown t12 - t13, t22 - t23, t32 - t33 time periods), the resistance detection unit continuously detects the real - time resistance R of the heating resistor and sends it to the microprocessor, and the microprocessor subtracts the real - time resistance R obtained during this time period from the initial resistance R0 to get the real - time change amplitude value of the resistance as R - R0.

[0091] S5. When the microprocessor analyzes and determines that T ≤ T1 and R - R0 ≥ R1, the microprocessor controls the power adjustment unit to immediately turn off the output and prohibits it from supplying power to the heating resistor again for dry - burning protection.

[0092] S6. When the microprocessor analyzes and determines that T > T1 and R - R0 ≥ R2, the microprocessor controls the power adjustment unit to temporarily turn off the power supply to the heating resistor for temporary dry - burning protection.

[0093] In the above steps, the e-liquid remaining amount detection unit includes a timer, and the detection of the e-liquid remaining amount is achieved by the method of timing with the timer. This timer belongs to the detection unit that can detect and calculate the e-liquid remaining amount equally. Since there is a certain amount of e-liquid stored in the atomizer, under the condition of the same power, the heating resistor can consume it after working for a certain period of time. There is a corresponding relationship between the total e-liquid amount value L0 and the total duration during which the e-liquid is consumed, that is, the total duration T0 during which the heating resistor can work. The real-time value L of the e-liquid remaining amount and the real-time value T of the remaining duration during which the heating resistor can work are also corresponding. Therefore, the detection of the e-liquid remaining amount can be equivalently replaced by detecting the remaining duration during which the heating resistor can work, that is, the e-liquid remaining amount detection unit can be specifically designed as a timer for detecting the working duration of the heating resistor. In addition, every time the user takes a puff of smoke, the start switch is turned on once, and then the heating resistor is powered on once, and the duration of the power-on is the duration of each puff of smoke, that is, the working duration of the start switch corresponds to the working duration of the heating resistor. Therefore, the timer can accumulate the working time of the start switch, that is, accumulate the already working duration Ta of the start switch (corresponding to the already working duration of the heating resistor) and send it to the microprocessor. If the set total working duration of the heating resistor is T0 (which can be converted into the total e-liquid amount value L0), the microprocessor can calculate the real-time value T of the remaining duration during which the heating resistor can work as T = T0 - Ta. The real-time value T of the remaining duration during which the heating resistor can work is equivalent to the real-time value L of the e-liquid remaining amount.

[0094] If the microprocessor reads and judges that the real-time value T of the e-liquid remaining amount ≤ T1, and reads and judges that the resistance change amplitude value R - R0 of the real-time resistance R during each puff of the user relative to the initial resistance R0 ≥ R1, that is, at this time, because the e-liquid in the atomizer is almost insufficient, and the resistance change amplitude value during each puff has exceeded the set value, so the microprocessor judges that the heating resistor has a real dry burn and controls the power adjustment unit to turn off the output and prohibits it from supplying power to the heating resistor again. In this way, it can accurately judge that the e-liquid in the atomizer is close to the minimum limit, and avoid continuing to supply power to the atomizer with almost no e-liquid, and avoid the user inhaling the smoky smell and causing an unpleasant use experience.

[0095] Meanwhile, if the microprocessor reads and determines that the remaining e-liquid value T > T1, and reads and determines that the resistance change amplitude value R - R0 ≥ R2, that is, the e-liquid in the atomizer is still sufficient at this time, but due to the different placement angles of the atomizer, the liquid supply is not timely or sufficient, resulting in a temporary lack of e-liquid around the heating resistor and causing a temporary dry burn. Therefore, the microprocessor determines that the heating resistor may have a temporary dry burn and controls the power adjustment unit to temporarily turn off the output, so that the heating resistor pauses working. If the liquid supply can be quickly restored around the heating resistor, when the user continues to draw and the detected resistance change amplitude value R - R0 < R2, the microprocessor controls the power adjustment unit to restore power supply to the heating resistor, and the e-cigarette can continue to work. In this case, the microprocessor can accurately judge the temporary dry burn of the heating resistor and perform temporary dry burn protection, which can also avoid the user inhaling the smoky smell and causing an unpleasant use experience.

[0096] Embodiment VIII

[0097] As Figure 4 shown, on the T time axis, t11 - t13, t21 - t23, t31 - t33 are the times for each puff. The time points of t11, t21, t31 are the time points when the start switch is turned on. The time points of t12, t22, t32 are the time points when the heating resistor is powered on. The time points of t13, t23, t33 are the time points when the heating resistor is powered off.

[0098] As Figure 4 shown, the time point when the start switch is turned on, which is also the start time point of the first puff, is t11. The time point when the heating resistor is powered off at the end of the first puff is t13. The start time point of the second puff is t21. The time interval between t13 and t21 is t. Similarly, the end time point of the second puff is t23. The start time point of the third puff is t31. The time interval between t23 and t31 is t.

[0099] Based on Embodiment VII, a dry-burn prevention control method for an e-cigarette in this embodiment includes the following steps:

[0100] In the circuit of the e-cigarette, a heating resistor, an e-liquid remaining amount detection unit, a resistance value detection unit, a microprocessor, an e-liquid data storage module, a start switch, and a power adjustment unit are electrically connected. The e-liquid remaining amount detection unit includes a timer. The power adjustment unit is set to output a constant power. In the e-liquid data storage module, the working duration margin threshold T1 = 35 seconds for the heating resistor when approaching dry burn is set. The first threshold for the resistance value increase of the heating resistor when dry burn occurs is set as R1 = 0.12Ω. The second threshold for the resistance value increase of the heating resistor that may have a dry burn is set as R2 = 0.17Ω. Another time interval threshold t1 = 3 seconds is set. Another total working duration T0 = 3500 seconds for the heating resistor is set.

[0101] S2. During each puff, from when the start switch is turned on until the heating resistor is powered off (such as the time periods t11 - t13, t21 - t23, t31 - t33 shown), the timer continuously detects the real-time remaining working duration value T of the heating resistor and sends it to the microprocessor. Additionally, the microprocessor obtains the time interval t between the end of the previous puff and the start of the current puff. Figure 4

[0102] S3. During each puff, from when the start switch is turned on until the heating resistor is powered on (such as the time periods t11 - t12, t21 - t22, t31 - t32 shown), the resistance detection unit continuously detects the real-time resistance R of the heating resistor and sends it to the microprocessor. The microprocessor sets the real-time resistance R obtained during this time period as the initial resistance R0. When the microprocessor analyzes and determines that t ≤ t1, it replaces the initial resistance R0 obtained during the current puff with the initial resistance R0 obtained during the previous puff. Figure 4

[0103] S4. During each puff, from when the heating resistor is powered on until it is powered off (such as the time periods t12 - t13, t22 - t23, t32 - t33 shown), the resistance detection unit continuously detects the real-time resistance R of the heating resistor and sends it to the microprocessor. The microprocessor subtracts the initial resistance R0 from the real-time resistance R obtained during this time period to get the real-time change amplitude value of the resistance as R - R0. Figure 4

[0104] S5. When the microprocessor analyzes and determines that T ≤ T1 and R - R0 ≥ R1, the microprocessor controls the power adjustment unit to immediately turn off the output and prohibit it from supplying power to the heating resistor again for dry-burning protection.

[0105] S6. When the microprocessor analyzes and determines that T > T1 and R - R0 ≥ R2, the microprocessor controls the power adjustment unit to temporarily turn off the power supply to the heating resistor for temporary dry-burning protection.

[0106] In the above steps, the microprocessor obtains the time interval t between the end of the previous puff and the start of the current puff, that is, the timer can detect and calculate the time interval t from the time when the power supply of the heating resistor is turned off (that is, the power adjustment unit is turned off) at the end of the previous puff to the time when the start switch is turned on at the start of the next puff. When the microprocessor determines that the time interval t is less than or equal to the time interval threshold t1, it is regarded that the user is puffing continuously and uninterruptedly, and the microprocessor calculates the initial resistance value R0 when the current puff is puffed according to the initial resistance value R0 of the previous puff. The above configuration is because if the user continuously and quickly puffs, the interval between each two puffs is very short, the heating resistor will work continuously without sufficient pause or standby time, and the temperature generated by the previous puff will not be able to drop quickly, that is, the resistance value will maintain a high resistance value, so the initial resistance value R0 detected by the current puff will also be high and cannot drop normally. At this time, the resistance change amplitude R-R0 is small and cannot reflect the dry burning state. Therefore, when the time interval t between each two puffs is less than the time interval threshold t1, the initial resistance value R0 of the current puff should be calculated according to the initial resistance value R0 of the previous puff, so as to truly reflect the large temperature increase during continuous puffing and the occurrence of dry burning.

[0107] In the above step S3, in the circuit configuration of the present invention, when the start switch is turned on, the power adjustment unit does not immediately output power to the heating resistor, but there is a certain delay, and the delay time can be designed to be 20 milliseconds. That is, during each puff, after the start switch is turned on and before the heating resistor is powered on, the resistance value detection unit detects the heating resistor in real time to obtain one or more real-time resistance values R and sends them to the microprocessor. The microprocessor sets the real-time resistance value R obtained during this period as the initial resistance value R0. In a preferred solution of this embodiment, the microprocessor takes the lowest value among the multiple real-time resistance values R obtained during this period and sets it as the initial resistance value R0. In other embodiments, the microprocessor can also take the average value of the multiple real-time resistance values R obtained during this period and set this average value as the initial resistance value R0, or take the first value or the last value among the multiple real-time resistance values R obtained during this period and set it as the initial resistance value R0. The initial resistance value R0 is set according to the real-time detected resistance value during each puff, so the initial resistance value of each puff is not a fixed value, but a value that changes according to the actual resistance value. The change of the initial resistance value R0 according to the actual situation helps to obtain the resistance value change amplitude value R - R0 within the range of each puff by comparing the real-time resistance value detected when the heating resistor is powered on, which can truly reflect the temperature rise amplitude within the range of each puff, so that the microprocessor can accurately judge whether dry burning occurs. It can be understood that since the temperature of the heating resistor rises during each puff by the user, the initial resistance value R0 of each puff will change, so the resistance value amplitude change R - R0 of each puff also changes. If R0 remains unchanged, the resistance value amplitude change R - R0 cannot truly reflect the actual change of the resistance value during each puff, which may lead to misjudgment of dry burning. Therefore, setting the real-time resistance value detected at the beginning of each puff as the initial resistance value R0 can accurately reflect whether dry burning actually occurs.

[0108] In the above step, if the microprocessor reads and judges that the real-time value L of the e-liquid remaining amount ≤ L1, and reads and judges that the resistance value change amplitude value R - R0 of the real-time resistance value R during each puff of the user relative to the initial resistance value R0 ≥ R1, that is, at this time, because the e-liquid in the atomizer is almost insufficient, and the resistance value change amplitude value during each puff has exceeded the set value, the microprocessor judges that the heating resistor has a real dry burning and controls the power adjustment unit to turn off the output and prohibits it from supplying power to the heating resistor again. In this way, it can accurately judge that the e-liquid in the atomizer is close to the minimum limit, and avoid continuously supplying power to the atomizer with almost no e-liquid, and prevent the user from inhaling the smoky smell and causing an unpleasant use experience.

[0109] Meanwhile, if the microprocessor reads and determines that the remaining e-liquid value L > L1, and reads and determines that the resistance change amplitude value R - R0 ≥ R2, that is, the e-liquid in the atomizer is still sufficient at this time, but due to the different placement angles of the atomizer, the liquid supply is not timely or sufficient, resulting in a temporary lack of e-liquid around the heating resistor and causing a temporary dry burn. Therefore, the microprocessor determines that the heating resistor may have a temporary dry burn and controls the power adjustment unit to temporarily turn off the output, so that the heating resistor stops working. If the liquid supply can be quickly restored around the heating resistor, when the user continues to suck and the detected resistance change amplitude value R - R0 < R2, the microprocessor controls the power adjustment unit to restore power supply to the heating resistor, and the e-cigarette can continue to work. In this case, the microprocessor can accurately determine the temporary dry burn of the heating resistor and perform temporary dry burn protection, which can also avoid the user inhaling the smoky smell and causing an unpleasant use experience.

[0110] In the above embodiment, the value range of L1 can also be set as (0.5% - 2%)L0, the value range of R1 can be set as 0.05Ω - 0.9Ω, the value range of R2 can be set as 0.09Ω - 1.0Ω; or the value range of T1 can be set as (0.5% - 2%)T0. Among them, the value range of L0 can also be set as (1 - 10)ml, the value range of T0 can be set as (400 - 4000) seconds, and the value range of t1 can be set as 2 - 4 seconds.

[0111] The above description only presents the preferred embodiments of the present invention, and the above specific embodiments are not limitations to the present invention. Within the scope of the technical idea of the present invention, various deformations and modifications can occur. Any retouching, modification or equivalent replacement made by those of ordinary skill in the art based on the above description shall fall within the scope protected by the present invention.

Claims

1. A method for preventing dry burning of an electronic cigarette, characterized in that: The following steps are involved: S1. In the circuit of the electronic cigarette, a heating resistor, a smoke liquid remaining amount detection unit, a resistance value detection unit, a microprocessor, a start switch and a power adjustment unit are electrically connected, and a smoke liquid remaining amount threshold L1 when dry burning is approaching is set, and a first threshold value R1 of the resistance value increase of the heating resistor when dry burning occurs is set; S2, during each puff, from the time when the start switch is turned on to the time when the heating resistor is powered off, the smoke liquid remaining amount detection unit detects in real time to obtain the real-time value L of the smoke liquid remaining amount and sends it to the microprocessor; S3, during each puff, after the start switch is turned on and before the heating resistor is powered on, the resistance detection unit detects the heating resistor in real time to obtain a real-time resistance R and sends it to the microprocessor, and the microprocessor sets the real-time resistance R obtained during this period as the initial resistance R0; S4, during each puff, from the time when the heating resistor is powered on to the time when the heating resistor is powered off, the resistance detection unit detects the heating resistor in real time to obtain a real-time resistance value R and sends it to the microprocessor, and the microprocessor subtracts the real-time resistance value R obtained during this period from the initial resistance value R0 to obtain a real-time change amplitude value of the resistance value R-R0; S5. When the microprocessor analyzes and determines that L≤L1 and R-R0≥R1, the microprocessor controls the power regulating unit to immediately shut down the output and prohibits it from supplying power to the heating resistor again to perform anti-dry burning protection.

2. The electronic cigarette anti-dry burning control method according to claim 1, characterized in that: The step S1 also includes: setting the second threshold value of the resistance increase of the heating resistor that may cause dry burning to R2, and setting R2 to be greater than R1; and also includes step S6: when the microprocessor analyzes and determines that L>L1 and R-R0≥R2, the microprocessor controls the power regulation unit to temporarily shut down the power output to the heating resistor to perform temporary anti-dry burning protection.

3. The electronic cigarette anti-dry burning control method according to claim 1, characterized in that: The step S1 also includes: setting the power adjustment unit to a constant power output, the smoke liquid remaining detection unit includes a timer, and the smoke liquid remaining threshold L1 is equivalently replaced by the remaining threshold T1 of the working time of the heating resistor; the step S2 also includes: replacing the real-time value L of the smoke liquid remaining with the real-time value T of the working time of the heating resistor; the step S5 also includes: equivalently replacing the microprocessor analyzing and judging L≤L1 with analyzing and judging T≤T1.

4. The electronic cigarette anti-dry burning control method according to claim 2, characterized in that: The step S1 also includes: setting the power adjustment unit to a constant power output, the smoke liquid remaining detection unit includes a timer, and the smoke liquid remaining threshold value L1 is equivalently replaced by the remaining threshold value T1 of the working time of the heating resistor; the step S2 also includes: replacing the real-time value L of the smoke liquid remaining by the real-time value T of the working time of the heating resistor; the step S5 also includes: replacing the microprocessor's analysis and judgment of L≤L1 by equivalently replacing it with analysis and judgment of T≤T1; the step S6 also includes: replacing the microprocessor's analysis and judgment of L>L1 by analysis and judgment of T>T1.

5. The electronic cigarette anti-dry burning control method according to any one of claims 1 to 4, characterized in that: The step S1 further includes: setting a time interval threshold t1; the step S2 further includes: the microprocessor obtaining a time interval t between the end of the previous puff and the start of the current puff; the step S3 further includes: when the microprocessor analyzes and determines that t≤t1, replacing the initial resistance value R0 obtained during the current puff with the initial resistance value R0 obtained during the previous puff.

6. The electronic cigarette anti-dry burning control method according to any one of claims 1 to 4, characterized in that: In step S3, the microprocessor takes an average value of a plurality of real-time resistance values ​​R obtained during this period and sets the average value as the initial resistance value R0.

7. The electronic cigarette anti-dry burning control method according to any one of claims 1 to 4, characterized in that: In step S3, the microprocessor sets the lowest value among the multiple real-time resistance values ​​R obtained during this period as the initial resistance value R0.

8. The electronic cigarette anti-dry burning control method according to any one of claims 1 to 4, characterized in that: In step S3, the microprocessor sets the first value or the last value of the multiple real-time resistance values ​​R obtained during this period as the initial resistance value R0.

9. The electronic cigarette anti-dry burning control method according to claim 1, characterized in that: The value range of L1 is set to (0.5%-2%) L0, where L0 is the total value of the smoke liquid, and the value range of R1 is set to 0.05Ω-0.9Ω.

10. The electronic cigarette anti-dry burning control method according to claim 2, characterized in that: The value range of L1 is set to (0.5%-2%) L0, where L0 is the total value of the smoke liquid, the value range of R1 is set to 0.05Ω-0.9Ω, and the value range of R2 is set to 0.09Ω-1.0Ω.

11. The electronic cigarette anti-dry burning control method according to claim 9 or 10, characterized in that: Set the value range of L0 to 1ml-10ml.

12. The electronic cigarette anti-dry burning control method according to claim 3, characterized in that: The value range of T1 is set to (0.5%-2%)T0, where T0 is the total working time of the heating resistor, and the value range of R1 is set to 0.05Ω-0.9Ω.

13. The electronic cigarette anti-dry burning control method according to claim 4, characterized in that: The value range of T1 is set to (0.5%-2%)T0, where T0 is the total working time of the heating resistor, the value range of R1 is set to 0.05Ω-0.9Ω, and the value range of R2 is set to 0.09Ω-1.0Ω.

14. The electronic cigarette anti-dry burning control method according to claim 11 or 12, characterized in that: Set the value range of T0 to 400 seconds-4000 seconds.

15. The electronic cigarette anti-dry burning control method according to claim 5, characterized in that: Set the value range of t1 to 2-4 seconds.

16. A circuit for implementing the electronic cigarette anti-dry burning control method according to any one of claims 1-2, characterized in that: The invention comprises an electrically connected battery, a power regulating unit, a microprocessor, a start switch, a sampling reference resistor, a resistance detection unit, a smoke liquid remaining detection unit and a smoke liquid data storage module. When the start switch is turned on or off, the microprocessor controls the power regulating unit to output power to the heating resistor or shuts off the output. The resistance detection unit is used to detect the resistance R of the heating resistor in real time and transmit it to the microprocessor. The smoke liquid remaining detection unit is used to detect the real-time value L of the smoke liquid remaining in the atomizer in real time and transmit it to the microprocessor. The smoke liquid data storage module is used to store the initial resistance R0, the resistance R detected in real time, the real-time value L of the smoke liquid remaining and some thresholds and data set initially.

17. The electronic cigarette circuit according to claim 16, characterized in that: A timer is also included, which is used to detect and calculate the time interval t between the power supply of the heating resistor being turned off at the end of the previous puff and the start switch being turned on at the beginning of the next puff.

18. A circuit for implementing the electronic cigarette anti-dry burning control method according to any one of claims 3-4, characterized in that: The invention comprises an electrically connected battery, a power regulating unit, a microprocessor, a start switch, a sampling reference resistor, a resistance detection unit, a smoke liquid remaining detection unit and a smoke liquid data storage module. When the start switch is turned on or off, the microprocessor controls the power regulating unit to output power to the heating resistor or shuts off the output. The resistance detection unit is used to detect the resistance R of the heating resistor in real time and transmit it to the microprocessor. The smoke liquid remaining detection unit comprises a timer. The timer is used to accumulate the working time Ta of the heating resistor in real time and transmit it to the microprocessor. The smoke liquid data storage module is used to store the initial resistance R0, the resistance R detected in real time, the real-time value T of the remaining working time of the heating resistor and some threshold values ​​and data set initially.

19. The electronic cigarette circuit according to claim 18, characterized in that: The timer is also used to detect and calculate the time interval t between the power supply of the heating resistor being turned off at the end of the last puff and the start switch being turned on at the beginning of the next puff.

20. The electronic cigarette circuit according to claim 18, characterized in that: The atomizer circuit further comprises an anti-counterfeiting chip, and the anti-counterfeiting chip comprises an anti-counterfeiting data storage module and a smoke liquid data storage module.

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