A microgrid atomizer control circuit with low liquid medicine residue

Abstract

The invention discloses a microgrid atomizer control circuit with low liquid medicine residue. A pulse width modulation (PWM) signal of a single chip microcomputer is electrically connected to a grid of a field effect tube to control the on and off of the field effect tube. The source of the field effect tube is electrically connected to a third resistor R3, a shell of the third resistor R3 is grounded, a drain of the field effect tube is electrically connected to a middle lead end of a three-pin inductor, a left lead end of an inductor L1 is electrically connected to a plate of a capacitor C1, a right lead end of the inductor L1 is electrically connected to a first pin of a USB connector, and a fourth pin of the USB connector is also electrically connected to the drain of the field effect tube. The invention directly uses a single chip microcomputer to generate a PWM signal wave of a fixed frequency to supply the field effect tube, and then boosts the voltage through a three-pin inductor, and the boosted square wave enters an atomizing sheet, and the atomizing sheet can break up water droplets and atomize the water droplets. The PWM signal wave has the advantages of high flexibility, energy saving, low hardware requirements, easy programming and control, and enhanced noise resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of atomizers, and in particular relates to a microgrid atomizer control circuit with low drug liquid residue. Background Art

[0002] With the development of industry, air pollution is serious, and the number of patients with respiratory diseases has greatly increased due to the sudden cold and warm weather during the transition of seasons. At present, diseases such as bronchial asthma, respiratory viral infections and pneumonia are at a high incidence, and atomization inhalation is one of the most effective methods for treating these diseases. Because the drug directly enters the respiratory tract and lungs, the target organ, through inhalation, it is faster and more effective than oral drugs, and its dosage is only one-tenth of other drug administration methods at most, which significantly reduces the toxic side effects of drugs, especially for children. In inhalation therapy, how to deliver drugs to the patient's respiratory tract and lungs, the inhalation device plays a key role.

[0003] The residual liquid volume of the nebulizer is an important performance indicator, which is directly related to the drug use efficiency of each treatment. The national standard stipulates that the residual liquid volume of the nebulizer cup should be ≤1mL. This standard is intended to ensure the effectiveness of nebulization treatment and avoid reducing the treatment effect due to excessive drug residue. Too much residual liquid means that after the treatment, more drugs will still remain in the nebulizer cup, which not only wastes the drugs, but also affects the treatment effect for treatments that require precise control of drug dosage. The smaller the residual volume, the more complete the nebulization. The low residual volume of the drug liquid is economical and cost-effective. The amount of residual liquid is related to the control of the host. The transformer capacitor resonant circuit of the host is composed of inductance and capacitance. Usually, the input and output ends of the transformer are connected in series to form a resonant circuit. The inductance is formed by the coil of the transformer, and the capacitance is added to the circuit through external components. The capacitance of the capacitor and the inductance of the inductor can be adjusted as needed to achieve the desired resonant frequency.

[0004] The transformer capacitor resonant circuit in the prior art has the following disadvantages: 1. Calculation and adjustment of the resonant frequency: The resonant frequency needs to be calculated according to actual needs, and the parameters of the capacitor and inductor need to be adjusted to achieve the desired resonance effect. 2. Control of the quality factor: The quality factor refers to the degree of energy loss in the circuit, which needs to be controlled within a reasonable range to ensure the efficiency and stability of the circuit. 3. Impedance matching problem: The impedance of the input and output ends needs to be matched to ensure the effective transmission of energy. 4. Overvoltage, overcurrent and other problems: Appropriate protection measures need to be taken to avoid overvoltage, overcurrent and other problems in the circuit to ensure the stability and safety of the circuit. Summary of the invention

[0005] The invention provides a microgrid atomizer control circuit with low drug liquid residue to solve the existing problems.

[0006] To solve the above problems, the technical solution provided by the present invention is as follows:

[0007] An embodiment of the present invention provides a microgrid atomizer control circuit with low liquid medicine residue, including a power supply, a single-chip microcomputer, a field effect tube, a three-pin inductor L1, a capacitor C1, a USB connector and an atomizer sheet, wherein the single-chip microcomputer is electrically connected to the power supply, and the pulse width modulation PWM signal of the single-chip microcomputer is electrically connected to the gate of the field effect tube to control the on and off of the field effect tube; the source of the field effect tube is electrically connected to the third resistor R3, the shell of the third resistor R3 is grounded, the drain of the field effect tube is electrically connected to the middle lead terminal 2 of the three-pin inductor, the left lead terminal 1 of the inductor L1 is electrically connected to one plate of the capacitor C1, a 5V voltage is loaded on the first capacitor C1 plate, the right lead terminal 3 of the inductor L1 is electrically connected to the first pin 1 of the USB connector, and the fourth pin 4 of the USB connector is also electrically connected to the drain of the field effect tube.

[0008] In an optional embodiment of the present invention, when the field effect tube receives a PWM signal, when the PWM signal outputs a high level, the three-legged inductor is charged, and its electrical energy is converted into magnetic energy. At the same time, the capacitor C1 stores charge and accumulates positive charge; when the PWM signal outputs a low level, the current flowing through the inductor L1 will decrease, and the inductor L1 releases energy to hinder the current from decreasing. The current passing through the inductor L1 will slowly decrease. At this time, the charge will continue to accumulate at both ends of the atomizer sheet, and the two ends of the atomizer sheet will obtain a larger voltage to complete the boost action; through the continuous change of the PWM signal, the value of the input voltage is boosted to drive the atomizer sheet to work.

[0009] In an optional embodiment of the present invention, the output frequency of the single-chip microcomputer controls the resonant frequency and the output duty cycle of the atomizer sheet; when the output frequency and the atomizer sheet do not match, the single-chip microcomputer cannot control the atomization of the atomizer sheet; when the output frequency and the atomizer sheet match, the single-chip microcomputer can control the atomization of the atomizer sheet, and the single-chip microcomputer needs to set the PWM wave output frequency to be the same as the resonant frequency of the atomizer sheet to drive atomization; when the duty cycle of the PWM signal output is relatively small, the atomization amount of the atomizer sheet is small.

[0010] In an optional embodiment of the present invention, the frequency of the pulse width modulation (PWM) signal provided by the single chip microcomputer is 108KHZ.

[0011] In an optional embodiment of the present invention, a first resistor R1 is further connected in series between the pulse width modulation (PWM) signal of the single chip microcomputer and the gate of the field effect tube.

[0012] In an optional embodiment of the present invention, a diode Z1 is connected in parallel across both ends of the first resistor R1.

[0013] In an optional embodiment of the present invention, the gate of the field effect tube is also electrically connected to one end of a second resistor R2, and a shell of the second resistor R2 is grounded.

[0014] Compared with the prior art, the embodiment of the present invention provides a microgrid atomizer control circuit with low liquid residue, which has the following beneficial effects: the present invention directly uses a single-chip microcomputer to generate a fixed frequency PWM signal wave to supply a field effect tube, and then boosts the voltage through a three-pin inductor. The boosted square wave enters the atomizer, and the atomizer can break up the water droplets and atomize the water droplets. Advantages of PWM signal wave: 1. High flexibility: PWM technology allows the single-chip microcomputer to generate analog signals in a digital way, thereby realizing precise control of various devices. By adjusting the pulse width, the output voltage or current can be flexibly controlled; 2. Energy saving: PWM technology can effectively reduce power consumption. When a lower output voltage or current is required, the overall power consumption can be reduced by reducing the pulse width instead of reducing the power supply voltage; 3. Low hardware requirements: Compared with using a dedicated analog circuit, the single-chip microcomputer system using PWM technology has lower hardware requirements and reduces system costs. 4. Easy to program and control: The generation and control of PWM signals are relatively simple, and most single-chip microcomputer programming languages ​​provide direct support for PWM functions; 5. Enhanced noise resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 A schematic diagram of a control circuit of a microgrid atomizer with low drug liquid residue provided in an embodiment of the present application.

[0017] Figure 2 A schematic diagram of the specific connection relationship of a microgrid atomizer control circuit with low drug liquid residue provided in an embodiment of the present application.

[0018] Figure 3 A schematic diagram of the single-chip microcomputer output frequency of a microgrid atomizer control circuit with low liquid medicine residue provided in an embodiment of the present application.

[0019] Figure 4 A power supply schematic diagram of a microgrid atomizer control circuit with low drug liquid residue provided in an embodiment of the present application.

[0020] Figure 5 A schematic diagram of the correspondence between the microcontroller gear position and the residual liquid amount of a microgrid atomizer control circuit with low liquid residue provided in an embodiment of the present application. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0022] The embodiment of the present invention provides a microgrid atomizer control circuit with low liquid medicine residue. The working principle of the microgrid atomizer control circuit is as follows: the circuit is driven by a certain frequency oscillation, so that the piezoelectric ceramic atomizer plate undergoes resonance changes, thereby driving the metal mesh to oscillate at high speed, so that the liquid medicine passes through the numerous tiny mesh holes on the metal mesh and is quickly ejected, forming countless tiny atomized particles. The diameter of the atomized particles is generally within 5μm, so the amount of residual liquid is relatively small. The present invention changes the atomization rate by controlling the duty cycle of the PWM signal wave of the single-chip microcomputer, and the residual liquid amount of the atomization is ≤0.1mL through testing.

[0023] Specifically, Figure 1 and Figure 2 As shown, a control circuit of a microgrid atomizer with low liquid medicine residue includes a power supply, a single-chip microcomputer, a field effect tube, a three-pin inductor L1, a capacitor C1, a USB connector and an atomizer. Among them, the single-chip microcomputer is electrically connected to the power supply. The pulse width modulation PWM signal of the single-chip microcomputer is electrically connected to the gate of the field effect tube to control the on and off of the field effect tube; the source of the field effect tube is electrically connected to the third resistor R3, the shell of the third resistor R3 is grounded, the drain of the field effect tube is electrically connected to the middle lead terminal 2 of the three-pin inductor, the left lead terminal 1 of the inductor L1 is electrically connected to one plate of the capacitor C1, and a 5V voltage is loaded on the first capacitor C1 plate, the right lead terminal 3 of the inductor L1 is electrically connected to the first pin 1 of the USB connector, and the fourth pin 4 of the USB connector is also electrically connected to the drain of the field effect tube.

[0024] When the field effect tube receives a PWM signal, when the PWM signal outputs a high level, the three-legged inductor is charged, and its electrical energy is converted into magnetic energy. At the same time, the capacitor C1 stores charge and accumulates positive charge; when the PWM signal outputs a low level, the current flowing through the inductor L1 will decrease, and the inductor L1 releases energy to hinder the current from decreasing. The current passing through the inductor L1 will slowly decrease. At this time, the charge will continue to accumulate at both ends of the atomizer sheet, and the two ends of the atomizer sheet will obtain a larger voltage to complete the boost action; through the continuous change of the PWM signal, the value of the input voltage is boosted to drive the atomizer sheet to work.

[0025] like Figure 3As shown, the output frequency of the microcontroller controls the resonant frequency and output duty cycle of the atomizer; when the output frequency does not match the atomizer, the microcontroller cannot control the atomizer; when the output frequency matches the atomizer, the microcontroller can control the atomizer. The microcontroller needs to set the PWM wave output frequency to be the same as the resonant frequency of the atomizer to drive the atomization; when the duty cycle of the PWM signal output is relatively small, the atomization amount of the atomizer is small. The pulse width modulation PWM signal frequency provided by the microcontroller is 108KHZ.

[0026] like Figure 2 As shown, a first resistor R1 is connected in series between the pulse width modulation PWM signal of the single chip and the gate of the field effect tube. A diode Z1 is connected in parallel at both ends of the first resistor R1. The gate of the field effect tube is also electrically connected to one end of a second resistor R2, and the shell of the second resistor R2 is grounded.

[0027] like Figure 4 As shown, the power circuit is directly provided with 5V / 1A power by the power adapter.

[0028] The present invention also provides a microgrid atomizer control method with low liquid medicine residue, comprising the following steps:

[0029] Step 1: The circuit board is electrically connected to the atomizer, and the power adapter provides power to the microcontroller. Step 2: Select a brand new atomizer, and test the microcontroller and the atomizer one-on-one. Step 3: The circuit board selects the maximum atomization gear and starts atomization. Step 4: After the atomization is completed, the remaining liquid in the atomizer can be calculated. Step 5: The test results are as follows: Figure 5 shown.

[0030] Among them, residual liquid volume inspection: use an electronic balance with an accuracy of not less than 0.01g to measure the mass m5 of the atomizer cup assembly (microgrid), inject physiological saline into the atomizer cup to the maximum scale, the water temperature is 20℃±5℃, start the atomizer, and adjust the atomization rate to the maximum until there is no water in the atomizer sheet and the atomizer port no longer produces mist. Use a balance to measure the total mass m6 of the atomizer sheet assembly (microgrid) and the remaining water at this time, and calculate the residual liquid volume according to formula (1) as follows:

[0031] (1), where: C is the residual liquid volume, in mL; m5 is the mass of the nebulizer cup assembly (microgrid), in grams; m6 is the total mass of the nebulizer cup assembly (microgrid) and the remaining water after nebulization, in grams; ρ is the density of saline, in g / mL.

[0032] In summary, although the present invention has been disclosed as above in terms of preferred embodiments, the above preferred embodiments are not intended to limit the present invention. A person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined in the claims.

Claims

1. A microgrid atomizer control circuit with low liquid residue, characterized in that: It includes a power supply, a single-chip computer, a field effect tube, a three-pin inductor L1, a capacitor C1, a USB connector and an atomizer, wherein the single-chip computer is electrically connected to the power supply, the pulse width modulation PWM signal of the single-chip computer is electrically connected to the gate of the field effect tube to control the on and off of the field effect tube; the source of the field effect tube is electrically connected to the third resistor R3, the shell of the third resistor R3 is grounded, the drain of the field effect tube is electrically connected to the middle lead terminal 2 of the three-pin inductor, the left lead terminal 1 of the inductor L1 is electrically connected to one plate of the capacitor C1, a 5V voltage is loaded on the plate of the first capacitor C1, the right lead terminal 3 of the inductor L1 is electrically connected to the first pin 1 of the USB connector, and the fourth pin 4 of the USB connector is also electrically connected to the drain of the field effect tube.

2. A microgrid atomizer control circuit with low liquid medicine residue according to claim 1, characterized in that: When the field effect tube receives a PWM signal, when the PWM signal outputs a high level, the three-legged inductor is charged, and its electrical energy is converted into magnetic energy. At the same time, the capacitor C1 stores charge and accumulates positive charge; when the PWM signal outputs a low level, the current flowing through the inductor L1 will decrease, and the inductor L1 releases energy to prevent the current from decreasing. The current passing through the inductor L1 will slowly decrease. At this time, the charge will continue to accumulate at both ends of the atomizer sheet, and the two ends of the atomizer sheet will obtain a larger voltage to complete the boost action; through the continuous change of the PWM signal, the value of the input voltage is boosted to drive the atomizer sheet to work.

3. A microgrid atomizer control circuit with low liquid medicine residue according to claim 2, characterized in that: The output frequency of the single-chip microcomputer controls the resonant frequency and output duty cycle of the atomizer sheet; when the output frequency does not match the atomizer sheet, the single-chip microcomputer cannot control the atomizer sheet to atomize; when the output frequency matches the atomizer sheet, the single-chip microcomputer can control the atomizer sheet to atomize, and the single-chip microcomputer needs to set the PWM wave output frequency to be the same as the resonant frequency of the atomizer sheet to drive atomization; when the duty cycle of the PWM signal output is relatively small, the atomization amount of the atomizer sheet is small.

4. A microgrid atomizer control circuit with low liquid medicine residue according to claim 3, characterized in that: The pulse width modulation (PWM) signal frequency provided by the microcontroller is 108KHZ.

5. The microgrid atomizer control circuit with low liquid medicine residue according to claim 1, characterized in that: A first resistor R1 is also connected in series between the pulse width modulation (PWM) signal of the single chip and the gate of the field effect tube.

6. A microgrid atomizer control circuit with low liquid medicine residue according to claim 5, characterized in that: A diode Z1 is connected in parallel across two ends of the first resistor R1.

7. A microgrid atomizer control circuit with low liquid medicine residue according to claim 6, characterized in that: The gate of the field effect tube is also electrically connected to one end of a second resistor R2, and a shell of the second resistor R2 is grounded.

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