Ultrasonic nebulizer

Abstract

The application discloses an ultrasonic atomizer, which comprises a liquid storage cavity for storing a liquid matrix, an ultrasonic atomizing sheet for generating oscillation to atomize the liquid matrix, a controller, a control circuit and a power supply. The control circuit comprises a power supply branch, a switch branch, a resonance branch and an impedance branch. The power supply branch is used to generate a direct current power supply according to the power supply. The switch branch is used to turn on and off in response to a first pulse signal output by the controller to generate a pulse voltage according to the direct current power supply. The resonance branch is used to resonate in response to the turning on and off of the switch branch to output a driving voltage of the ultrasonic atomizing sheet according to the pulse voltage. The impedance branch is connected between the resonance branch and the ultrasonic atomizing sheet, and is used to match the impedance of the combination of the impedance branch and the ultrasonic atomizing sheet with the impedance of the combination of the power supply branch, the switch branch and the resonance branch. In this way, the working efficiency of the ultrasonic atomizer can be improved.

Description

Technical Field

[0001] This application relates to the field of ultrasonic atomizer technology, and in particular to an ultrasonic atomizer. Background Technology

[0002] In daily life, ultrasonic atomizers can be used in many fields such as humidification, fragrance addition, sterilization, decoration, medical atomization, and e-cigarettes.

[0003] Among them, the ultrasonic atomizer uses ultrasonic atomization technology to achieve the atomization function. Specifically, in the ultrasonic atomizer, the ultrasonic atomizing plate can convert electrical energy into ultrasonic energy. At room temperature, the ultrasonic energy can atomize water-soluble atomizing liquid into tiny mist particles of 1μm to 5μm. Thus, water can be used as a medium to spray water-soluble atomizing liquid into a mist using ultrasonic directional pressure.

[0004] However, in the existing technology, there is a lot of additional energy loss when driving the ultrasonic atomizing plate, resulting in low working efficiency of the ultrasonic atomizer. Summary of the Invention

[0005] The present application aims to provide an ultrasonic atomizer that can improve the working efficiency of ultrasonic atomizers.

[0006] In a first aspect, this application provides an ultrasonic atomizer, comprising:

[0007] A liquid storage chamber is used to store a liquid matrix;

[0008] An ultrasonic atomizing plate is used to generate oscillations to atomize the liquid matrix;

[0009] Controller, control circuit and power supply;

[0010] The control circuit includes:

[0011] A power supply branch, connected to the power supply, is used to generate DC power according to the power supply.

[0012] A switch branch is connected to the controller and the power supply branch respectively, and is used to turn on and off in response to the first pulse signal output by the controller, so as to generate a pulse voltage according to the DC power supply;

[0013] The resonant branch is connected to the power supply branch and the switch branch respectively, and is used to resonate in response to the conduction and disconnection of the switch branch, so as to drive the driving voltage of the ultrasonic atomizing plate according to the pulse voltage output.

[0014] An impedance branch is connected between the resonant branch and the ultrasonic atomizing plate. The impedance branch is used to match the impedance of the combination of the impedance branch and the ultrasonic atomizing plate with the impedance of the combination of the power supply branch, the switch branch and the resonant branch.

[0015] In one alternative embodiment, the power supply branch includes a first inductor;

[0016] The first end of the first inductor is connected to the power supply, and the second end of the first inductor is connected to the switching branch and the resonant branch respectively.

[0017] In one alternative embodiment, the switching branch includes a switching transistor;

[0018] The first terminal of the switching transistor is connected to the controller, the second terminal of the switching transistor is grounded, and the third terminal of the switching transistor is connected to the power supply branch and the resonant branch respectively.

[0019] In an alternative embodiment, the switching branch further includes a first capacitor, a first terminal of which is connected to a third terminal of the switching transistor, and a second terminal of which is grounded.

[0020] The first capacitor is used to charge when the switch is off and the current flowing through the resonant branch is less than a first current threshold, and to discharge when the switch is off and the current flowing through the resonant branch is greater than or equal to the first current threshold, resonating with the resonant branch.

[0021] Specifically, the switch is turned on when the first capacitor discharges to the second current threshold.

[0022] In one alternative, when the switch is off, the frequency at which the combination of the first capacitor and the resonant branch resonates is less than the frequency of the ultrasonic atomizing sheet.

[0023] When the switch is turned on, the frequency of the resonant branch is greater than the frequency of the ultrasonic atomizing sheet.

[0024] In one alternative embodiment, the frequency of the ultrasonic atomizing plate is any frequency in the range of [2.9MHz-3.1MHz].

[0025] When the switch is off, the frequency at which the combination of the first capacitor and the resonant branch resonates is any frequency in the range of [2MHz-3MHz].

[0026] When the switch is turned on, the resonant branch resonates at any frequency in the range of [3.2MHz-4MHz].

[0027] In one alternative embodiment, the switching branch further includes a first resistor and a second resistor connected in series;

[0028] The first end of the circuit formed by the first resistor and the second resistor connected in series is connected to the controller, the second end of the circuit formed by the first resistor and the second resistor connected in series is grounded, and the connection point between the first resistor and the second resistor is connected to the first end of the switching transistor.

[0029] In one alternative embodiment, the resonant branch includes a second capacitor and a second inductor;

[0030] The first end of the second capacitor is connected to the power supply branch and the switch branch respectively, the second end of the second capacitor is connected to the first end of the second inductor, and the second end of the second inductor is connected to the impedance branch.

[0031] In one alternative embodiment, the resonant branch includes a sixth capacitor and the primary winding of a transformer;

[0032] The first terminal of the sixth capacitor is connected to the power supply branch and the switch branch respectively, the second terminal of the sixth capacitor is connected to the first terminal of the primary winding, and the second terminal of the primary winding is grounded.

[0033] In one alternative embodiment, the impedance branch includes a sixth inductor and the secondary winding of the transformer;

[0034] The first end of the sixth inductor is connected to the first end of the secondary winding of the transformer, the second end of the sixth inductor is connected to the ultrasonic atomizing sheet, and the second end of the secondary winding of the transformer is grounded.

[0035] In one alternative embodiment, the impedance branch includes a third capacitor;

[0036] The first terminal of the third capacitor is connected to the resonant branch and the ultrasonic atomizing sheet, respectively, and the second terminal of the third capacitor is grounded.

[0037] In one alternative embodiment, the impedance branch further includes a third inductor;

[0038] The first end of the third inductor is connected to the first end of the third capacitor and the resonant branch, respectively, and the second end of the third inductor is connected to the ultrasonic atomizing sheet; or, the first end of the third inductor is connected to the resonant branch, and the second end of the third inductor is connected to the first end of the third capacitor and the ultrasonic atomizing sheet, respectively.

[0039] In one alternative embodiment, the impedance of the combination of the impedance branch and the ultrasonic atomizing plate includes a real part and an imaginary part. When the real part of the impedance is equal to the impedance of the combination of the power supply branch, the switching branch, and the resonant branch, and the imaginary part of the impedance is zero, the impedance of the combination of the impedance branch and the ultrasonic atomizing plate matches the impedance of the combination of the power supply branch, the switching branch, and the resonant branch.

[0040] In one alternative embodiment, the control circuit further includes a drive branch;

[0041] The switch branch is connected to the controller through the drive branch, and the drive branch is connected to the power supply;

[0042] The driving branch is used to receive the first pulse signal and output a second pulse signal to the switching branch according to the first pulse signal and the power supply, wherein the driving capability of the second pulse signal is stronger than that of the first pulse signal.

[0043] In one alternative embodiment, the drive branch includes a drive chip, which includes a power input terminal, at least one signal input terminal, and at least one signal output terminal.

[0044] The power input terminal is connected to the power source, the signal input terminal is connected to the controller, and the signal output terminal is connected to the switch branch.

[0045] The signal input terminal is used to input the first pulse signal, and the signal output terminal is used to output the second pulse signal.

[0046] In one alternative embodiment, the control circuit further includes a current detection branch;

[0047] The current detection branch is connected to the power supply, the power supply branch and the controller respectively, and the current detection branch is used to detect the current flowing into the power supply branch.

[0048] In one alternative embodiment, the current sensing branch includes an amplifier and a third resistor, the third resistor being connected to the amplifier, the power supply branch, and the power supply, respectively, and the amplifier being connected to the controller;

[0049] The amplifier is configured to output a detection voltage based on the voltage across the third resistor, so that the controller determines the current flowing into the power supply branch based on the detection voltage.

[0050] The ultrasonic nebulizer provided in this application allows for resonance of the resonant branch during the operation of the ultrasonic atomizing plate. This is achieved by switching the switching branch on or off, causing the resonant branch to exhibit pure resistance, thus reducing the reactive power portion and power loss, thereby improving the efficiency of the ultrasonic nebulizer. Consequently, the resonant branch has the lowest impedance, the highest current, and the highest output driving voltage, exceeding the power supply voltage. This enables the boosting of the power supply voltage to drive the ultrasonic nebulizer. Furthermore, by using an impedance branch to match the impedance of the impedance branch and the ultrasonic atomizing plate with the impedance of the power supply branch, the switching branch, and the resonant branch, the reactive power portion of the impedance branch and the ultrasonic atomizing plate combination is reduced, further minimizing power loss and improving the efficiency of the ultrasonic nebulizer. Attached Figure Description

[0051] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0052] Figure 1 This is a schematic diagram of the structure of the ultrasonic atomizer provided in the embodiments of this application;

[0053] Figure 2 This is a schematic diagram of the structure of an ultrasonic atomizer provided in another embodiment of this application;

[0054] Figure 3 This is a schematic diagram of the control circuit provided in an embodiment of this application;

[0055] Figure 4 A schematic diagram of the circuit structure of the control circuit provided in the embodiments of this application;

[0056] Figure 5 A schematic diagram of the circuit structure of a control circuit provided in another embodiment of this application;

[0057] Figure 6 This is a schematic diagram of the control circuit provided in another embodiment of this application;

[0058] Figure 7 A schematic diagram of the circuit structure of the control circuit provided in another embodiment of this application. Detailed Implementation

[0059] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0060] An ultrasonic atomizer according to an embodiment of this application improves efficiency by setting a resonant branch to provide a driving voltage for the ultrasonic atomizing plate after boosting the power supply. Simultaneously, an impedance branch is used to achieve impedance matching of the ultrasonic atomizing plate, further reducing its reactive power and improving efficiency.

[0061] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the ultrasonic atomizer provided in an embodiment of this application. Figure 1 As shown, the ultrasonic nebulizer 100 includes a liquid storage chamber 11, an ultrasonic nebulizing plate 12, a controller 13, a control circuit 14, and a power supply 15.

[0062] The liquid storage chamber 11 is used to store a liquid matrix, which may include different substances depending on the application scenario. For example, in the field of electronic atomization, it may contain nicotine and / or fragrances and / or aerosol generating substances (e.g., glycerin). In the field of medical atomization, it may include drugs with disease treatment or health benefits and / or solvents such as saline.

[0063] The ultrasonic atomizing plate 12 is in fluid communication with the liquid storage chamber 11. The ultrasonic atomizing plate 12 can be directly disposed in the liquid storage chamber 11, or the atomizing chamber containing the ultrasonic atomizing plate 12 can be directly connected to the liquid storage chamber 11, or liquid can be transferred between the ultrasonic atomizing plate 12 and the liquid storage chamber 11 through a liquid-absorbing medium. It is used to generate oscillations to atomize the liquid matrix, that is, to atomize the liquid matrix transmitted to or near the ultrasonic atomizing plate 12 into an aerosol through vibration. Specifically, during use, the ultrasonic atomizing plate 12 disperses the liquid matrix through high-frequency vibration (preferably a vibration frequency of 1.7MHz to 4.0MHz, exceeding the range of human hearing and belonging to the ultrasonic frequency band) to generate aerosols with naturally suspended particles.

[0064] The controller 13 may be a microcontroller unit (MCU) or a digital signal processing (DSP) controller, etc. The controller 13 is electrically connected to the control circuit 14, and the controller 13 can be used to control at least one electronic component in the control circuit 14. The control circuit 14 is electrically connected to the ultrasonic atomizing plate 12, and the control circuit 14 is used to provide driving voltage and driving current to the ultrasonic atomizing plate 12 according to the power supply 15. In one embodiment, the controller 13 and the control circuit 14 may be disposed on a printed circuit board (PCB).

[0065] Power source 15 is used for power supply. In one embodiment, power source 15 is a battery. The battery can be a lithium-ion battery, lithium metal battery, lead-acid battery, nickel-metal hydride battery, lithium-sulfur battery, lithium-air battery, or sodium-ion battery, etc., and is not limited thereto. In terms of scale, the battery in this embodiment can be a single cell, or a battery module composed of multiple cells connected in series and / or parallel, etc., and is not limited thereto. Of course, in other embodiments, the battery may include more or fewer components, or have different component configurations, and this embodiment does not limit this.

[0066] In one embodiment, the ultrasonic atomizer 100 further includes a liquid transfer medium 16, an air outlet channel 17, an upper housing 18, and a lower housing 19.

[0067] The liquid transfer element 16 is used to transfer the liquid matrix between the liquid storage chamber 11 and the ultrasonic atomizing plate 12.

[0068] The exhaust channel 17 is used to output inhalable vapor or aerosol generated by the liquid matrix for users to inhale.

[0069] The upper housing 18 and the lower housing 19 are detachably connected. In one embodiment, the upper housing 18 and the lower housing 19 can be detachably connected through a snap-fit ​​structure or a magnetic attraction structure. The upper housing 18 and the lower housing 19 together serve to house and protect other components. The liquid storage chamber 11, the ultrasonic atomizing plate 12, the liquid transfer element 16, and the air outlet channel 17 are all disposed within the upper housing 18, while the controller 13, the control circuit 14, and the power supply 15 are all disposed within the lower housing 19.

[0070] The upper housing 18 and the lower housing 19 are detachably aligned in a functional relationship. Various mechanisms can be used to connect the lower housing 19 to the upper housing 18, resulting in threaded engagement, press-fit engagement, interference fit, magnetic engagement, etc. In some embodiments, when the upper housing 18 and the lower housing 19 are in an assembled configuration, the ultrasonic atomizer 100 may be substantially rod-shaped, cylindrical, bar-shaped, columnar, etc.

[0071] The upper housing 18 and the lower housing 19 can be formed of any suitable structurally sound material. In some examples, the upper housing 18 and the lower housing 19 can be formed of metals or alloys such as stainless steel or aluminum. Other suitable materials include various plastics (e.g., polycarbonate), metal-plated plastic, ceramics, and so on.

[0072] It should be noted that, as Figure 1 The hardware structure of the ultrasonic atomizer 100 shown is merely an example, and the ultrasonic atomizer 100 may have more or fewer components than those shown in the figure, may combine two or more components, or may have different component configurations. The various components shown in the figure can be implemented in hardware, software, or a combination of hardware and software, including one or more signal processing and / or application-specific integrated circuits. For example, as... Figure 2 As shown, the ultrasonic atomizing plate 12 can be placed in the liquid storage chamber 11, which can save the liquid transmission element 16 and help save costs.

[0073] At the same time, it is understandable that Figure 1 or Figure 2 The ultrasonic nebulizer 100 shown can be applied to various occasions and plays different roles, and this application embodiment does not impose specific limitations on it. For example, in one embodiment, the ultrasonic nebulizer 100 is applied in the medical field. In this case, the ultrasonic nebulizer 100 can be a medical nebulizer, which can atomize the liquid medicine added inside and allow the patient to inhale it to achieve the effect of adjuvant therapy. As another example, in another embodiment, the ultrasonic nebulizer 100 can also be used as an electronic product, such as an electronic cigarette. An electronic cigarette is an electronic product that uses atomization or other means to turn nicotine solution, etc., into an aerosol for the user to inhale.

[0074] Please refer to the following: Figure 3 , Figure 3 This is a schematic diagram of the ultrasonic atomizer circuit structure provided in an embodiment of this application. Figure 3 As shown, the control circuit 14 includes a power supply branch 141, a switch branch 142, a resonant branch 143, and an impedance branch 144.

[0075] Specifically, power supply branch 141 is connected to power supply 15, switch branch 142 is connected to controller 12 and power supply branch 141 respectively, resonant branch 143 is connected to power supply branch 141 and switch branch 142 respectively, and impedance branch 144 is connected between resonant branch 143 and ultrasonic atomizing plate 12. Specifically, the first end of power supply branch 141 is connected to power supply 15, the second end of power supply branch 141 is connected to the first end of switch branch 142 and the first end of resonant branch 143 respectively, the second end of switch branch 142 is connected to controller 13, the second end of resonant branch 143 is connected to the first end of impedance branch 144, and the second end of impedance branch 144 is connected to the first end of ultrasonic atomizing plate 12.

[0076] Specifically, power supply branch 141 is used to generate DC power according to power supply 15. Switching branch 142 is used to turn on and off in response to a first pulse signal output by controller 13 to generate a pulse voltage according to the DC power supply. Resonant branch 143 is used to resonate in response to the on and off of switching branch 142 to output a driving voltage for driving ultrasonic atomizing plate 12 according to the pulse voltage. Impedance branch 144 is used to match the impedance of the combination of impedance branch 144 and ultrasonic atomizing plate 12 with the impedance of the combination of power supply branch 141, switching branch 142 and resonant branch 143.

[0077] In this embodiment, when the ultrasonic atomizing plate 12 needs to be driven, firstly, the power supply 15 is converted into DC power output after passing through the power supply branch 141. Simultaneously, the controller 13 outputs a first pulse signal to control the switching branch 142 to continuously cycle between on and off, thereby converting the DC power output from the power supply branch 141 into AC power, i.e., pulse voltage. Subsequently, after resonance occurs, the resonant branch 143 can boost the received pulse voltage and use the boosted driving voltage to drive the ultrasonic atomizing plate 12. Since the resonant branch 143 achieves resonance, it essentially exhibits pure resistance, reducing the reactive power portion of the resonant branch 143, i.e., reducing power loss, thereby improving the working efficiency of the ultrasonic atomizer 100. Furthermore, in this case, the impedance of the resonant branch 143 is minimal, the current is maximum, and a larger driving voltage can be output to drive the ultrasonic atomizing plate 12 to operate stably.

[0078] Furthermore, the ultrasonic atomizing plate 12 can be equivalent to a capacitive load. After the resonant branch 143 resonates, the combination of the power supply branch 141, the switch branch 142 and the resonant branch 143 results in a purely resistive output. If energy is directly transferred between the two (i.e., the capacitive load and the purely resistive output), a large amount of reactive power will be generated, which will lead to a significant reduction in the efficiency of driving the ultrasonic atomizing plate 12.

[0079] Therefore, in this embodiment, an impedance branch 144 is also provided to match the impedance of the combination of the impedance branch 144 and the ultrasonic atomizing plate 12 with the impedance of the combination of the power supply branch 141, the switch branch 142, and the resonant branch 143. This reduces the reactive power portion of the combination of the impedance branch 144 and the ultrasonic atomizing plate 12, thereby reducing power loss. The ultrasonic atomizing plate 12 can obtain higher driving energy, improving the efficiency of driving the ultrasonic atomizing plate 12 and also improving the working efficiency of the ultrasonic atomizer 100.

[0080] Specifically, in one embodiment, the impedance (Zh) of the combination of impedance branch 144 and ultrasonic atomizing plate 12 includes a real part (Rh) and an imaginary part (j*Xh). When the real part of the impedance is equal to the impedance (Z0) of the combination of power supply branch 141, switch branch 142 and resonant branch 143, and the imaginary part of the impedance is zero, the impedance of the combination of impedance branch 144 and ultrasonic atomizing plate 12 matches the impedance of the combination of power supply branch 141, switch branch 142 and resonant branch 143.

[0081] Where Zh = Rh + j*Xh. Furthermore, since the impedance of the combination of power supply branch 141, switch branch 142, and resonant branch 143 is purely resistive, Z0 = R0, where R0 represents the resistance of the combination of switch branch 142 and resonant branch 143. Therefore, to ensure that the impedance of the combination of impedance branch 144 and ultrasonic atomizing plate 12 matches the impedance of the combination of power supply branch 141, switch branch 142, and resonant branch 143, the following conditions must be met: Rh = R0, and j*Xh = 0. At this point, the ultrasonic atomizing plate 12 has higher operating efficiency.

[0082] In different applications, the above conditions can be achieved in various ways, and this application does not impose specific limitations on them. For example, in one embodiment, firstly, a suitable load is configured in the resistor branch 144 so that Rh = R0, at which point the ultrasonic atomizing plate 12 can obtain the maximum driving power. Secondly, the resistor branch 144 needs to be further configured with an impedance opposite to the capacitive reactance of the ultrasonic atomizing plate 12 to cancel its capacitive reactance and eliminate the useless work caused by its capacitive reactance.

[0083] In one embodiment, such as Figure 4 As shown, the power supply branch 141 includes a first inductor L1. The first end of the first inductor L1 is connected to the power supply 15, and the second end of the first inductor L1 is connected to the switching branch 142 and the resonant branch 143, respectively.

[0084] Specifically, the first inductor L1 is a high-frequency choke. A high-frequency choke significantly impedes high-frequency alternating current, has minimal impediment to low-frequency alternating current, and even less impede direct current (DC). Therefore, it can be used to "pass DC while blocking AC, pass low frequencies, and block high frequencies." Thus, the first inductor L1 allows DC to pass through to provide energy to subsequent circuits, enabling the output of DC power according to power supply 15. Additionally, the first inductor L1 can also prevent high-frequency short circuits.

[0085] Figure 4 One exemplary structure of the switch branch 142 is also shown, such as Figure 4 As shown, the switching branch 142 includes a switching transistor Q1. The first terminal of the switching transistor Q1 is connected to the controller 13, the second terminal of the switching transistor Q1 is grounded to GND, and the third terminal of the switching transistor Q1 is connected to the power supply branch 141 and the resonant branch 143 respectively.

[0086] In this embodiment, the switching transistor Q1 is an N-type metal-oxide-semiconductor field-effect transistor (NMOS transistor). Specifically, the gate of the NMOS transistor is the first terminal of the switching transistor Q1, the source of the NMOS transistor is the second terminal of the switching transistor Q1, and the drain of the NMOS transistor is the third terminal of the switching transistor Q1.

[0087] In addition, in other embodiments, the switching transistor Q1 can also be a P-type metal-oxide-semiconductor field-effect transistor or a signal relay. The switching transistor Q1 can also be at least one of a transistor, an insulated-gate bipolar transistor, an integrated gate-commutated thyristor, a gate-turn-off thyristor, a junction-gate field-effect transistor, a MOS-controlled thyristor, a gallium nitride-based power device, a silicon carbide-based power device, and a silicon controlled rectifier.

[0088] In one embodiment, the switch branch 142 further includes a first resistor R1 and a second resistor R2 connected in series. The first terminal of the circuit formed by the series connection of the first resistor R1 and the second resistor R2 is connected to the controller 13, the second terminal of the circuit formed by the series connection of the first resistor R1 and the second resistor R2 is grounded to GND, and the connection point between the first resistor R1 and the second resistor R2 is connected to the first terminal of the switch transistor Q1.

[0089] In this embodiment, the first resistor R1 and the second resistor R2 are used to divide the voltage of the first pulse signal output by the controller 13 to obtain the voltage at the first terminal of the switch Q1. When the voltage across the second resistor R2 is greater than the turn-on voltage of the switch Q1, the switch Q1 is turned on; otherwise, the switch Q1 is turned off.

[0090] In one embodiment, the switch branch 142 further includes a first capacitor C1, the first end of which is connected to the third end of the switch transistor Q1, and the second end of the first capacitor C1 is grounded to GND.

[0091] Specifically, the first capacitor C1 is used to charge when the switch Q1 is off and the current flowing through the resonant branch 143 is less than a first current threshold, and to discharge when the switch Q1 is off and the current flowing through the resonant branch 143 is greater than or equal to the first current threshold, resonating with the resonant branch 143. When the first capacitor C1 discharges to the second current threshold, the switch Q1 is turned on.

[0092] It is understood that the settings of the first current threshold and the second current threshold are both related to the parameters of the first capacitor C1 and the resonant branch 143. In other words, in different application scenarios, different first current thresholds and second current thresholds can be obtained by selecting different first capacitors C1 and resonant branches 143. This application embodiment does not impose specific limitations on this.

[0093] In this embodiment, the first capacitor C1 serves to hysteresis the voltage. Specifically, when the switch Q1 is turned off, the voltage between the second and third terminals of the switch Q1 does not suddenly rise; instead, it maintains the voltage across the first capacitor C1. The voltage between the second and third terminals of the switch Q1 only begins to rise after the current between them drops to zero. This achieves soft turn-off of the switch Q1.

[0094] Meanwhile, the current flowing through the resonant branch 143 is less than the first current threshold, and the first capacitor C1 is charged. Then, the current in the resonant branch 143 gradually increases until it is greater than or equal to the first current threshold. At this point, the current in the resonant branch 143 is greater than the current in the first inductor L1, and the first capacitor C1 resonates with the resonant branch 143, discharging. Subsequently, when the first capacitor C1 discharges to the second current threshold, the switch Q1 turns on. It can be seen that by selecting appropriate first capacitor C1 and resonant branch 143 to make the second current threshold zero, zero-voltage turn-on of the switch Q1 can be achieved, that is, soft turn-on of the switch Q1 is realized.

[0095] It's understandable that when a transistor (such as switching transistor Q1) is in a switching state, it can theoretically achieve 100% efficiency. However, due to the influence of transistor barrier capacitance, diffusion capacitance, and distributed capacitance in the circuit, the transistor requires a certain transition time from saturation to cutoff or from cutoff to saturation. This results in significant increases in collector current and collector voltage during the transition time, leading to increased power dissipation. Typically, parasitic capacitance is not very large, and its effect can be ignored at low operating frequencies. However, at higher operating frequencies, the increase in power dissipation cannot be ignored, reducing efficiency and even damaging the device.

[0096] Therefore, in this embodiment, by setting the first capacitor C1 and the resonant branch 143, the soft switching process (including soft turn-on and soft turn-off) of the switching transistor Q1 can be realized, that is, the product of voltage and current is always zero when the switching transistor Q1 is turned on and off. As a result, the switching loss of the switching transistor Q1 is also close to zero, the switching efficiency of the switching transistor Q1 is high, and thus the working efficiency of the ultrasonic atomizer 100 is also improved.

[0097] Subsequently, in one embodiment, in order to ensure that the switching transistor Q1 can operate in a soft-switching state, the following parameters can be configured: First, when the switching transistor Q1 is off, the frequency of the combined resonance of the first capacitor C1 and the resonant branch 143 (denoted as the first resonant frequency) is configured to be less than the frequency of the ultrasonic atomizing plate 12. At the same time, when the switching transistor Q1 is on, the frequency of the resonant branch 143 (denoted as the second resonant frequency) is configured to be greater than the frequency of the ultrasonic atomizing plate 12.

[0098] The first resonant frequency and the second resonant frequency can be configured according to the actual ultrasonic atomizing sheet 12 selected, and this application embodiment does not impose specific restrictions on this.

[0099] For example, in an optional embodiment, the selected ultrasonic atomizing plate 12 has a frequency of any frequency in the range of [2.9MHz-3.1MHz]. The first resonant frequency can then be any frequency in the range of [2MHz-3MHz], and the second resonant frequency can be any frequency in the range of [3.2MHz-4MHz]. For instance, if the ultrasonic atomizing plate has a frequency of 3MHz, the first resonant frequency is 2.5MHz, and the second resonant frequency is 4MHz, then the first resonant frequency is less than the frequency of the ultrasonic atomizing plate, and the frequency of the ultrasonic atomizing plate is less than the second resonant frequency. This allows for soft switching of the switching transistor Q1, improving its switching efficiency.

[0100] For example, in another optional embodiment, if the selected ultrasonic atomizing plate 12 has a frequency of any frequency in the range of [10KHz-10MHz], then the first resonant frequency and the second resonant frequency can be set according to the actual frequency of the ultrasonic atomizing plate 12 used, as long as the first resonant frequency is less than the frequency of the ultrasonic atomizing plate and the frequency of the ultrasonic atomizing plate is less than the second resonant frequency. For example, if the actual frequency of the ultrasonic atomizing plate 12 used is 2.4MHz or 2.7MHz, the first resonant frequency can be any frequency in the range of [1.5MHz-2MHz], and the second resonant frequency can be any frequency in the range of [3MHz-3.5MHz]. If the actual frequency of the ultrasonic atomizing plate 12 used is 130KHz or 160KHz, then the first resonant frequency can be any frequency in the range of [100KHz-120KHz], and the second resonant frequency can be any frequency in the range of [180KHz-200KHz].

[0101] Figure 4 One exemplary structure of the resonant branch 143 is also shown, such as Figure 4 As shown, the resonant branch 143 includes a second capacitor C2 and a second inductor L2. The first end of the second capacitor C2 is connected to the power supply branch 141 (i.e., the second end of the first inductor L1) and the switching branch 142 (i.e., the third end of the switching transistor Q1), respectively. The second end of the second capacitor C2 is connected to the first end of the second inductor L2, and the second end of the second inductor L2 is connected to the impedance branch 144.

[0102] In this embodiment, when the second capacitor C2 and the second inductor L2 form a series resonance, the circuit composed of the second capacitor C2 and the second inductor L2 is purely resistive. At this time, the impedance is at its minimum and the current is at its maximum. A high voltage N times larger than the pulse voltage input to the resonant branch 143 is generated across the second capacitor C2 and the second inductor L2, where N is greater than 1. This high voltage is used to drive the ultrasonic atomizing plate 12. Consequently, the ultrasonic atomizing plate 12 can obtain sufficient driving energy, which is beneficial for maintaining the stable operation of the ultrasonic atomizing plate 12.

[0103] Figure 5 Another illustrative structure of the resonant branch 143 is also shown, such as Figure 5 As shown, the resonant branch 143 includes a sixth capacitor C6 and the primary winding L4 of the transformer. The first terminal of the sixth capacitor C6 is connected to both the power supply branch 141 and the switch branch 142, and the second terminal of the sixth capacitor C6 is connected to the first terminal of the primary winding L4. The second terminal of the primary winding L4 is grounded to GND.

[0104] In this embodiment, the resonance between the sixth capacitor C6 and the primary winding L4 of the transformer is similar to the resonance between the second capacitor C2 and the second inductor L2, which is easily understood by those skilled in the art and will not be elaborated further here.

[0105] In one embodiment, such as Figure 4 As shown, the impedance branch 144 includes a third capacitor C3 and a third inductor L3. The first end of the third inductor L3 is connected to the first end of the third capacitor C3 and the resonant branch 143, and the second end of the third inductor L3 is connected to the ultrasonic atomizing plate 12.

[0106] It should be noted that, Figure 4 The embodiment shown is only one example of the structure of impedance branch 144. In other embodiments, impedance branch 144 may also be other structures. This application does not impose specific limitations on this, as long as the impedance of the combination of impedance branch 144 and ultrasonic atomizing plate 12 can be matched with the impedance of the combination of power supply branch 141, switch branch 142 and resonant branch 143.

[0107] For example, in one embodiment, the impedance branch 144 may consist of only the third capacitor C3. In this case, the first terminal of the third capacitor C3 is connected to both the resonant branch 143 and the ultrasonic atomizing plate 12, and the second terminal of the third capacitor C3 is grounded to GND.

[0108] For example, in another embodiment, the impedance branch 144 still includes a third capacitor C3 and a third inductor L3, and in this embodiment, the first end of the third inductor L3 is connected to the resonant branch 143, and the second end of the third inductor L3 is connected to the first end of the third capacitor C3 and the ultrasonic atomizing sheet 12 respectively.

[0109] For example, in yet another implementation, such as Figure 5 As shown, the impedance branch includes the sixth inductor L6 and the secondary winding L5 of the transformer. The first end of the sixth inductor L6 is connected to the first end of the secondary winding L5 of the transformer, the second end of the sixth inductor L6 is connected to the ultrasonic atomizing plate 12, and the second end of the secondary winding L5 of the transformer is grounded to GND.

[0110] In one embodiment, please continue to refer to Figure 5 The control circuit 14 also includes a sixth resistor R6, a seventh resistor R7, and an eighth resistor R8. The first end of the sixth resistor R6 is connected to the first end of the sixth inductor L6, the second end of the sixth resistor R6 is connected to the first end of the seventh resistor R7, the second end of the seventh resistor R7 and the first end of the eighth resistor R8 are both grounded to GND, and the second end of the eighth resistor R8 is connected to the ultrasonic atomizing plate 12.

[0111] In this embodiment, the sixth resistor R6 and the seventh resistor R7 are used to implement the voltage detection function, and the eighth resistor R8 is used to implement the current detection function.

[0112] The following are Figure 4 The working principle of the circuit structure shown will be introduced.

[0113] Before the switching transistor Q1 is turned off, Q1 is in the on state. Power supply 15 forms a loop through the first inductor L1, the switching transistor Q1, and ground GND, storing energy from power supply 15 in the first inductor L1. The first inductor L1 has a large inductance value and stores a lot of energy, so it can be equivalent to a constant current source.

[0114] Next, the first pulse signal output by controller 13 is at a low level, the switch Q1 is turned off, and the current that originally flowed through switch Q1 is transferred to the first capacitor C1, so the current in switch Q1 is 0. Power supply 15, first inductor L1, and first capacitor C1 form a circuit, and power supply 15 begins to charge the first capacitor C1. The voltage across the first capacitor C1 gradually increases, and at this time, the current in resonant branch 143 gradually decreases from negative to zero axis.

[0115] When the current in the first inductor L1 equals the current in the first capacitor C1, the current in the resonant branch 143 and the ultrasonic atomizing plate 12 is 0. The current in the resonant branch 143 and the ultrasonic atomizing plate 12 changes from negative to positive and gradually increases. When the current in the resonant branch 143 equals the current in the first inductor L1, the current flowing through the first capacitor C1 is 0, and at this time, the voltage across the first capacitor C1 reaches its maximum value.

[0116] As the current in the resonant branch 143 increases further, and exceeds the current in the first inductor L1, the first capacitor C1 begins to discharge. The voltage across the first capacitor C1 gradually decreases. When the charge stored in the first capacitor C1 is completely discharged, the first pulse signal output by the controller 13 switches from a low level to a high level, and the switch Q1 is turned on. It can be seen that when the switch Q1 is turned on, the voltage between the second and third terminals of the switch Q1 (i.e., the voltage across the first capacitor C1) is zero, so no losses occur when the switch Q1 is turned on.

[0117] Subsequently, after the switching transistor Q1 is turned on, the first capacitor C1 is short-circuited, and the voltage across the first capacitor C1 is 0. At this time, the initial current flowing through the switching transistor Q1 is 0 and begins to gradually increase, while the current in the resonant branch 143 gradually decreases. When the current flowing through the switching transistor Q1 equals the current in the first inductor L1, the current in the resonant branch 143 is 0.

[0118] The current in the resonant branch 143 changes from 0 to negative, and the current amplitude gradually increases, while the current flowing through the switch Q1 remains in the rising phase. The power supply 15 stores the energy in the first inductor L1 again until the first pulse signal output by the controller 13 switches from a high level to a low level again, at which point the switch Q1 is turned off again.

[0119] The above process is repeated cyclically to drive the ultrasonic atomizing plate 12. During this process, on the one hand, the first capacitor C1, the second capacitor C2, and the first inductor L2 work together to achieve a soft-switching process for the switching transistor Q1, minimizing damage to Q1 and thus increasing the operating efficiency of the ultrasonic atomizer 100. On the other hand, by setting up an impedance branch 144 to match the impedance of the combination of the impedance branch 144 and the ultrasonic atomizing plate 12 with the impedance of the combination of the power supply branch 141, the switching branch 142, and the resonant branch 143, the wasted power generated by the ultrasonic atomizing plate 12 is reduced, resulting in higher driving efficiency for the ultrasonic atomizing plate 12 and further improving the operating efficiency of the ultrasonic atomizer 100.

[0120] In one embodiment, such as Figure 6As shown, the control circuit 14 also includes a drive branch 145. The switch branch 142 is connected to the controller 13 via the drive branch 145, and the drive branch drives the drive branch 145 to be connected to the power supply 15. Specifically, the second end of the switch branch 142 is connected to the first end of the drive branch 145, the second end of the drive branch 145 is connected to the controller 13, and the third end of the drive branch 145 is connected to the power supply 15.

[0121] Specifically, the drive branch 145 receives the first pulse signal output by the controller 13 and outputs a second pulse signal to the switch branch 142 based on the first pulse signal and the power supply 15. The second pulse signal has a stronger driving capability than the first pulse signal. Therefore, the drive branch 145 amplifies the first pulse signal output by the controller 13 and outputs the second pulse signal to more efficiently drive the rapid switching of the switch transistor Q1 in the switch branch 142.

[0122] Figure 7 An exemplary structure of the drive branch 145 is shown in the figure, such as Figure 7 As shown, the drive branch 145 includes a drive chip U1, which includes a power input terminal, at least one signal input terminal, and at least one signal output terminal. In this embodiment, the power input terminal is pin 6 of the drive chip U1, the at least one signal input terminal includes pin 2 of the drive chip U1, and the at least one signal output terminal includes pin 5 of the drive chip U1.

[0123] The power input terminal is connected to power supply 15, the signal input terminal is connected to controller 13, and the signal output terminal is connected to switch branch 142. The signal input terminal is used to input a first pulse signal, and the signal output terminal is used to output a second pulse signal.

[0124] Specifically, pin 6 of driver chip U1 is connected to power supply 15. Pin 2 of driver chip U1 is connected to controller 13. Pin 5 of driver chip U1 is connected to switch branch 142. Pin 2 of driver chip U1 is used to input a first pulse signal, and pin 5 of driver chip U1 is used to output a second pulse signal.

[0125] In this embodiment, by configuring the driver chip U1, the driving capability of the pulse signal output by the controller 13 is improved. This enables rapid driving of the switch sub-branch 142, maintaining stable operation of the ultrasonic atomizing plate 12. Simultaneously, the greater the current input to pin 6 of the driver chip U1, the stronger the driving capability output from pin 5 of the driver chip U1.

[0126] In one embodiment, the driver chip U1 can be an integrated chip of model SGM48000. Of course, other models of integrated chips can also be used in other embodiments, and this application does not limit this. Furthermore, since there are different types of driver chips, the specific pin definitions may differ when using other types of driver chips, but the functions and signal definitions are the same. Therefore, if other types of driver chips are selected, they can be configured in a manner similar to the above embodiments, which is readily understood by those skilled in the art and will not be elaborated further here.

[0127] In this embodiment, power supply 15 is used as the input power source for the driver chip U1. In other words, in this embodiment, power supply 15 simultaneously powers both the driver chip U1 and the ultrasonic atomizing plate 12 to save costs. In other embodiments, to prevent the driver chip U1 and the ultrasonic atomizing plate 12 from interfering with each other during operation, two different power supplies can be used to power the driver chip U1 and the ultrasonic atomizing plate 12 respectively, thereby improving the stability of their operation.

[0128] In one embodiment, such as Figure 6 As shown, the control circuit 14 also includes a current detection branch 146. The current detection branch 146 is connected to the power supply 15, the power supply branch 141, and the controller 13. Specifically, the first end of the current detection branch 146 is connected to the power supply 15, the second end of the current detection branch 146 is connected to the power supply branch 141, and the third end of the current detection branch 146 is connected to the controller 13.

[0129] In this embodiment, the current detection branch 146 is used to detect the current flowing into the power supply branch 141. Subsequently, the controller 13 can determine whether the ultrasonic atomizing plate 12 has an abnormality such as excessive current during operation based on the current, so that it can be dealt with in a timely manner when an abnormality occurs, which helps to reduce the risk of damage to the ultrasonic atomizing plate 12.

[0130] Figure 7 An exemplary structure of the current detection branch 146 is shown in the figure, such as Figure 7 As shown, the current detection branch 146 includes an amplifier U2 and a third resistor R3. The third resistor R3 is connected to both the amplifier U2 and the power supply branch 141, and the amplifier U2 is connected to the controller 13.

[0131] Specifically, the first end of the third resistor R3 is connected to the power supply 15 and the non-inverting input of the amplifier U2, the second end of the third resistor R3 is connected to the inverting input of the amplifier U2 and the first end of the first inductor L1, the output of the amplifier U2 is connected to the controller 13, the grounding terminal of the amplifier U2 is grounded to GND, and the power supply terminal of the amplifier U2 is connected to the voltage V1.

[0132] In this embodiment, amplifier U2 is configured to output a detection voltage based on the voltage across the third resistor R3, so that controller 13 can determine the current flowing into power supply branch 141 based on the detection voltage. Specifically, amplifier U2 can amplify the received voltage across the third resistor R3 by a factor of K before outputting the detection voltage, where K is a positive integer. Subsequently, after acquiring the detection voltage, controller 13 can determine the current flowing into power supply branch 141 based on the relationship between the detection voltage and the current flowing into power supply branch 141.

[0133] In one embodiment, the current detection branch 146 further includes a fourth capacitor C4, a fifth capacitor C5, a fourth resistor R4, and a fifth resistor R5. The fourth capacitor C4 and the fifth capacitor C5 are filter capacitors, the fifth resistor R5 is a current-limiting resistor, and the fourth resistor R4 is a pull-down resistor.

[0134] It should be noted that in the embodiments shown in the figures above, the resistor is presented as a single resistor, and the capacitor as a single capacitor. In other embodiments, the resistor may be an integration of series, parallel, or mixed resistors, and the capacitor may be an integration of series, parallel, or mixed capacitors.

[0135] The connection described in this application can be a direct connection, i.e., a connection between two components, or an indirect connection, i.e., an indirect connection between two components that can be formed through one or more elements.

[0136] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them; under the concept of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this application as described above, which are not provided in detail for the sake of brevity; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. An ultrasonic atomizer, characterized in that, include: A liquid storage chamber is used to store a liquid matrix; An ultrasonic atomizing plate is used to generate oscillations to atomize the liquid matrix; Controller, control circuit and power supply; The control circuit includes: A power supply branch, connected to the power supply, is used to generate DC power according to the power supply. A switch branch is connected to the controller and the power supply branch respectively, and is used to turn on and off in response to the first pulse signal output by the controller, so as to generate a pulse voltage according to the DC power supply; The resonant branch is connected to the power supply branch and the switch branch respectively, and is used to resonate in response to the conduction and disconnection of the switch branch, so as to drive the driving voltage of the ultrasonic atomizing plate according to the pulse voltage output. An impedance branch is connected between the resonant branch and the ultrasonic atomizing plate. The impedance branch is used to match the impedance of the combination of the impedance branch and the ultrasonic atomizing plate with the impedance of the combination of the power supply branch, the switch branch and the resonant branch. The switch branch includes a switch transistor; The first terminal of the switching transistor is connected to the controller, the second terminal of the switching transistor is grounded, and the third terminal of the switching transistor is connected to the power supply branch and the resonant branch respectively. The switching branch also includes a first capacitor, the first terminal of which is connected to the third terminal of the switching transistor, and the second terminal of which is grounded. The first capacitor is used to charge when the switch is off and the current flowing through the resonant branch is less than a first current threshold, and to discharge when the switch is off and the current flowing through the resonant branch is greater than or equal to the first current threshold, wherein when the current flowing through the resonant branch is greater than or equal to the first current threshold, the current in the resonant branch is greater than the current in the power supply branch, and the first capacitor discharges in resonance with the resonant branch. Specifically, when the first capacitor discharges to the second current threshold, the switch is turned on. The settings of the first current threshold and the second current threshold are both related to the parameters of the first capacitor and the resonant branch.

2. The ultrasonic atomizer according to claim 1, characterized in that, The power supply branch includes a first inductor; The first end of the first inductor is connected to the power supply, and the second end of the first inductor is connected to the switching branch and the resonant branch respectively.

3. The ultrasonic atomizer according to claim 1, characterized in that, When the switch is off, the frequency of the combined resonance of the first capacitor and the resonant branch is lower than the frequency of the ultrasonic atomizing sheet. When the switch is turned on, the frequency of the resonant branch is greater than the frequency of the ultrasonic atomizing sheet.

4. The ultrasonic atomizer according to claim 3, characterized in that, The frequency of the ultrasonic atomizing plate is any frequency in the range of [2.9MHz-3.1MHz]. When the switch is off, the frequency at which the combination of the first capacitor and the resonant branch resonates is any frequency in the range of [2MHz-3MHz]. When the switch is turned on, the resonant branch resonates at any frequency in the range of [3.2MHz-4MHz].

5. The ultrasonic atomizer according to claim 1, characterized in that, The switch branch also includes a first resistor and a second resistor connected in series; The first end of the circuit formed by the first resistor and the second resistor connected in series is connected to the controller, the second end of the circuit formed by the first resistor and the second resistor connected in series is grounded, and the connection point between the first resistor and the second resistor is connected to the first end of the switching transistor.

6. The ultrasonic atomizer according to claim 1, characterized in that, The resonant branch includes a second capacitor and a second inductor; The first end of the second capacitor is connected to the power supply branch and the switch branch respectively, the second end of the second capacitor is connected to the first end of the second inductor, and the second end of the second inductor is connected to the impedance branch.

7. The ultrasonic atomizer according to claim 1, characterized in that, The resonant branch includes the sixth capacitor and the primary winding of the transformer; The first terminal of the sixth capacitor is connected to the power supply branch and the switch branch respectively, the second terminal of the sixth capacitor is connected to the first terminal of the primary winding, and the second terminal of the primary winding is grounded.

8. The ultrasonic atomizer according to claim 7, characterized in that, The impedance branch includes the sixth inductor and the secondary winding of the transformer; The first end of the sixth inductor is connected to the first end of the secondary winding of the transformer, the second end of the sixth inductor is connected to the ultrasonic atomizing sheet, and the second end of the secondary winding of the transformer is grounded.

9. The ultrasonic atomizer according to claim 1, characterized in that, The impedance branch includes a third capacitor; The first terminal of the third capacitor is connected to the resonant branch and the ultrasonic atomizing sheet, respectively, and the second terminal of the third capacitor is grounded.

10. The ultrasonic atomizer according to claim 9, characterized in that, The impedance branch also includes a third inductor; The first end of the third inductor is connected to the first end of the third capacitor and the resonant branch, respectively, and the second end of the third inductor is connected to the ultrasonic atomizing sheet; or, the first end of the third inductor is connected to the resonant branch, and the second end of the third inductor is connected to the first end of the third capacitor and the ultrasonic atomizing sheet, respectively.

11. The ultrasonic nebulizer according to any one of claims 1-10, characterized in that, The impedance of the combination of the impedance branch and the ultrasonic atomizing plate includes a real part and an imaginary part. When the real part of the impedance is equal to the impedance of the combination of the power supply branch, the switch branch and the resonant branch, and the imaginary part of the impedance is zero, the impedance of the combination of the impedance branch and the ultrasonic atomizing plate matches the impedance of the combination of the power supply branch, the switch branch and the resonant branch.

12. The ultrasonic atomizer according to claim 1, characterized in that, The control circuit also includes a drive branch; The switch branch is connected to the controller through the drive branch, and the drive branch is connected to the power supply; The driving branch is used to receive the first pulse signal and output a second pulse signal to the switching branch according to the first pulse signal and the power supply, wherein the driving capability of the second pulse signal is stronger than that of the first pulse signal.

13. The ultrasonic atomizer according to claim 12, characterized in that, The driving branch includes a driving chip, which includes a power input terminal, at least one signal input terminal, and at least one signal output terminal. The power input terminal is connected to the power source, the signal input terminal is connected to the controller, and the signal output terminal is connected to the switch branch. The signal input terminal is used to input the first pulse signal, and the signal output terminal is used to output the second pulse signal.

14. The ultrasonic atomizer according to claim 1, characterized in that, The control circuit also includes a current detection branch; The current detection branch is connected to the power supply, the power supply branch and the controller respectively, and the current detection branch is used to detect the current flowing into the power supply branch.

15. The ultrasonic atomizer according to claim 14, characterized in that, The current detection branch includes an amplifier and a third resistor. The third resistor is connected to the amplifier, the power supply branch, and the power supply, respectively. The amplifier is connected to the controller. The amplifier is configured to output a detection voltage based on the voltage across the third resistor, so that the controller determines the current flowing into the power supply branch based on the detection voltage.

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