Humidifier atomizing circuit

Abstract

This invention discloses a humidifier atomizing circuit, including a microcontroller and an atomizing plate oscillation circuit. The atomizing plate oscillation circuit includes an atomizing plate, a first inductor, a second inductor, a first capacitor, a second capacitor, a first switching transistor, and a second switching transistor. The first capacitor is connected between the input and output terminals of the first switching transistor, and the first inductor is connected between the output terminal of the first switching transistor and a first power supply. The second capacitor is connected between the input and output terminals of the second switching transistor, and the second inductor is connected between the output terminal of the second switching transistor and the first power supply. The two ends of the atomizing plate are respectively connected to the output terminals of the first and second switching transistors. The control terminals of the first and second switching transistors are respectively connected to a first PWM pin and a second PWM pin defined by the microcontroller. The input terminals of the first and second switching transistors are connected and grounded through a resistor. This circuit can significantly improve the humidification efficiency of the humidifier.

Description

Technical Field

[0001] This invention relates to the field of humidifiers, and more particularly to a humidifier atomization circuit. Background Technology

[0002] With the development of technology, the humidifier industry has become increasingly mature, and the industry's requirements for humidifiers are becoming more and more stringent. For example, there are new requirements regarding noise levels, mist particle size, and humidification efficiency. International and domestic standards for humidifiers have clearly defined the relevant parameter requirements. The People's Republic of China National Standard GB / T23332-2018 specifies that humidification efficiency is divided into four levels from high to low: A, B, C, and D. The humidification efficiency should not be lower than level D. Specifically, for ultrasonic humidifiers, level A efficiency is specified as η≥13.5mL / h / W. Therefore, further upgrades and optimizations of humidifiers are necessary. Summary of the Invention

[0003] In view of the above-mentioned deficiencies of the prior art, the purpose of the present invention is to provide a humidifier atomization circuit that improves humidification efficiency and reduces the energy consumption of the humidifier.

[0004] To achieve the above objectives, the present invention provides a humidifier atomizing circuit, including a microcontroller and an atomizing plate oscillation circuit;

[0005] The atomizing plate oscillation circuit includes an atomizing plate, a first inductor, a second inductor, a first capacitor, a second capacitor, a first switching transistor, a second switching transistor, and a first resistor;

[0006] The first capacitor is connected between the input and output terminals of the first switching transistor, and the first inductor is connected between the output terminal of the first switching transistor and the first power supply.

[0007] The second capacitor is connected between the input and output terminals of the second switching transistor, and the second inductor is connected between the output terminal of the second switching transistor and the first power supply.

[0008] The two ends of the atomizing plate are respectively connected to the output terminal of the first switching transistor and the output terminal of the second switching transistor;

[0009] The control terminals of the first and second switching transistors are respectively connected to the first and second PWM pins defined by the microcontroller.

[0010] The input terminals of the first and second switching transistors are connected, and this connection point is connected to the power supply ground through the first resistor.

[0011] Furthermore, a third inductor is connected between the two legs of the atomizing plate.

[0012] Furthermore, the first and second switching transistors are NMOS transistors.

[0013] Furthermore, the first switch and the second switch are two switching units of a dual MOS transistor.

[0014] Furthermore, the first resistor comprises multiple resistors connected in parallel.

[0015] Furthermore, the humidifier atomizing circuit also includes a third switch, a fourth switch, and a third power supply. The control terminal of the third switch is connected to the fan control pin defined by the microcontroller. The input terminal of the third switch is grounded. The output stage of the third switch is connected to the control terminal of the fourth switch. The input terminal of the third switch is connected to the second power supply. The control terminal of the third switch is connected to the third power supply through a resistor. The output terminal of the third switch is connected to the control terminals of the first switch and the second switch through resistors respectively. The voltage of the third power supply is higher than the voltage of the second power supply.

[0016] Furthermore, the third switch is an NPN transistor, and the fourth switch is a PMOS transistor.

[0017] Furthermore, the humidifier atomization circuit also includes an atomization voltage monitoring circuit, which includes two voltage biasing circuits. The two ends of the first voltage biasing circuit are respectively connected to the power supply ground and the output terminal of the first switching transistor, and the voltage divider tap of the first voltage biasing circuit is connected to the first atomization voltage monitoring pin defined by the microcontroller. The two ends of the second voltage biasing circuit are respectively connected to the power supply ground and the output terminal of the second switching transistor, and the voltage divider tap of the second voltage biasing circuit is connected to the second atomization voltage monitoring pin defined by the microcontroller.

[0018] Furthermore, the humidifier atomization circuit also includes an atomization frequency tracking circuit, which includes a second resistor and a third capacitor. One end of the second resistor is connected to the connection node of the input terminal of the first switching transistor and the input terminal of the second switching transistor, and the other end of the second resistor is grounded through the third capacitor and connected to the atomization frequency tracking pin defined by the microcontroller.

[0019] The beneficial effects of this invention are:

[0020] This invention employs a dual LC oscillation circuit to increase the voltage difference across the atomizing plate under the same operating voltage, thereby greatly improving the humidification efficiency of the humidifier. Attached Figure Description

[0021] Figure 1 This is a circuit schematic diagram of a preferred embodiment of the present invention. Detailed Implementation

[0022] To further illustrate the various embodiments, the present invention provides accompanying drawings. These drawings are part of the disclosure of the present invention, primarily used to illustrate the embodiments and to explain the operating principles of the embodiments in conjunction with the relevant descriptions in the specification. With reference to these drawings, those skilled in the art should be able to understand other possible implementations and the advantages of the present invention. Components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0023] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0024] like Figure 1 As shown, this invention provides a humidifier atomization circuit, which consists of a microcontroller U1, an atomizing plate oscillation circuit, an atomization voltage monitoring circuit, and an atomization frequency tracking circuit. The atomizing plate oscillation circuit includes an atomizing plate P1, a dual LC oscillation circuit composed of inductors L11 and C10, and inductors L12 and C11, an inductor L13, dual MOSFETs Q1, and resistors R10, R11, and R12. The dual MOSFETs Q1 include two NMOS units, Q1-1 and Q1-2, which drive two LC drive circuits respectively. The rapid switching of high and low voltages by the dual MOSFETs Q1 forms the oscillation excitation. Due to the use of a dual LC oscillation circuit, the operating voltage across the atomizing plate P1 can be increased to twice the voltage provided by a single LC oscillation circuit. The voltage across the atomizing plate P1 determines its ability to convert electrical energy into mechanical energy. Simultaneously, using dual MOSFETs reduces the heat generated by the MOSFETs. Inductor L13 is used for matching the atomizing plate P1 and releasing oscillation energy. The connection node between the source of the first switch Q1-1 and the source of the second switch Q1-2 is grounded through parallel resistors R10, R11, and R12 to improve the overcurrent capacity of the circuit.

[0025] The atomization voltage monitoring circuit includes two voltage-dividing circuits composed of resistors R17 and R18, and R15 and R16. The oscillation signals LC_wave_B and LC_wave_A are divided and then fed back to pins 14 (WavP_B) and 3 (WavP_A) of the microcontroller U1, respectively. The atomization voltage monitoring circuit can monitor the output amplitude of the vibration circuit and adjust the switching frequencies of the first switch Q1-1 and the second switch Q1-2 of the dual MOSFETs Q1 in real time to maximize the voltage across the atomizer P1 and achieve the highest atomization efficiency.

[0026] The atomization frequency tracking circuit includes resistor R14 and capacitor C20. One end of resistor R14 is connected to the connection node between the source of the first switching transistor Q1-1 and the source of the second switching transistor Q1-2, and the other end is connected to pin 10 (Ineb) of microcontroller U1 and grounded through capacitor C20. This circuit is mainly used to collect the voltage across resistors R10, R11, and R12 to analyze the current passing through the atomizing plate. Combining this with the characteristics of the atomizing plate, the operating frequency of the atomizing plate is tracked and calculated, and then fed back to microcontroller U1.

[0027] In this embodiment, the power supply MCU_VDD of microcontroller U1 is 5V. The two gates of the dual MOSFET Q1 are connected to pin 7 (PWM_B) and pin 15 (PWM_A) of microcontroller U1, respectively. To ensure normal operation, the two gates of the dual MOSFET Q1 need to be pulled up, typically to the microcontroller's power supply MCU_VDD. However, the voltage and current of MCU_VDD are relatively low, resulting in weak driving capability. To address the insufficient driving capability of microcontroller U1, the two gates of the dual MOSFET Q1 can be pulled up to 12V via pull-up resistors R22 and R23, respectively. This pull-up voltage can be set as needed, and should be greater than the microcontroller's power supply MCU_VDD.

[0028] Due to voltage mismatch, a large leakage current will occur during standby. For energy saving and performance stability, the pull-up circuit needs to be turned off when the atomizing plate P1 is not working. Therefore, in this embodiment, the pull-up resistors R22 and R23 of the two gates of the dual MOSFET Q1 are connected to the 12V power supply through MOSFET Q22 and transistor Q21, controlled by pin 18 (ON / OFF) of the microcontroller U1. This pin is also used to turn the humidifier fan P4 on or off to achieve linkage control. In other embodiments, a separate pin can also be used for pull-up circuit control.

[0029] Experiments have verified that the dual-LC oscillation circuit of this embodiment improves humidification efficiency by more than 50% compared to the single-LC oscillation circuit. The humidifier using the atomization circuit of this embodiment can achieve a humidification efficiency η of 20 mL / h / W, far exceeding the minimum requirement for humidification efficiency grade A stipulated in the national standard.

[0030] In this embodiment, the 12V, 5V, and MCU_VDD power supplies are provided by the humidifier's power management circuit, which will not be further explained here.

[0031] In this embodiment, the operating voltage of the atomizing plate oscillation circuit is 12V, but it can also be applied and is not limited to conventional power supply circuits such as 5V / 24V / 34V, and can be used with atomizing plates of various frequencies.

[0032] In this embodiment, both the transistors and MOSFETs are used as switching transistors, and can be selected as needed, and can be used interchangeably to a certain extent. Therefore, a switching transistor can be used as a higher-level concept than the corresponding transistor and MOSFET, and the pin definitions for the switching transistor, transistor, and MOSFET are as follows:

[0033] Switching transistor triode MOSFET 1 Control pole base gate 2 Input pole emitter Source 3 Output pole collector Leakage level

[0034] Although the invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims, all of which shall be within the scope of protection of the invention.

Claims

1. A humidifier atomizing circuit, characterized in that, Includes a microcontroller (U1) and an atomizing plate oscillation circuit; The atomizing plate oscillation circuit includes an atomizing plate (P1), a first inductor (L12), a second inductor (L11), a first capacitor (C10), a second capacitor (C11), a first switching transistor (Q1-1), and a second switching transistor (Q1-2). The first capacitor (C10) is connected between the input and output terminals of the first switching transistor (Q1-1), and the first inductor (L12) is connected between the output terminal of the first switching transistor (Q1-1) and the first power supply (12V). The second capacitor (C11) is connected between the input and output terminals of the second switching transistor (Q1-2), and the second inductor (L11) is connected between the output terminal of the second switching transistor (Q1-2) and the first power supply (12V). The two ends of the atomizing plate (P1) are respectively connected to the output terminal of the first switching transistor (Q1-1) and the output terminal of the second switching transistor (Q1-2); The control terminals of the first switching transistor (Q1-1) and the second switching transistor (Q1-2) are respectively connected to the first PWM pin and the second PWM pin defined by the microcontroller (U1); The input terminal of the first switch (Q1-1) and the input terminal of the second switch (Q1-2) are connected, and this connection node is connected to the power supply ground (GND) through the first resistor. The atomizing plate oscillation circuit uses a microcontroller to coordinate the control of dual PWM signals, so that the voltages at both ends of the atomizing plate are superimposed. A third inductor (L13) is also connected between the two legs of the atomizing plate (P1). The first switch (Q1-1) and the second switch (Q1-2) are NMOS transistors.

2. The humidifier atomizing circuit as described in claim 1, characterized in that, The first switch (Q1-1) and the second switch (Q1-2) are two switching units of a dual MOSFET (Q1).

3. The humidifier atomizing circuit as described in claim 1, characterized in that, The first resistor comprises multiple resistors connected in parallel.

4. The humidifier atomizing circuit as described in claim 1, characterized in that, The humidifier atomization circuit also includes a third switching transistor (Q21), a fourth switching transistor (Q22), and a third power supply; The control electrode of the third switch (Q21) is connected to the fan control pin defined by the microcontroller (U1), the input electrode of the third switch (Q21) is grounded, and the output electrode of the third switch (Q21) is connected to the control electrode of the fourth switch (Q22). The input terminal of the fourth switch (Q22) is connected to the third power supply, and the output terminal of the fourth switch (Q22) is connected to the control terminal of the first switch (Q1-1) and the control terminal of the second switch (Q1-2) through resistors respectively.

5. The humidifier atomizing circuit as described in claim 4, characterized in that, The third switch (Q21) is an NPN transistor, and the fourth switch (Q22) is a PMOS transistor.

6. The humidifier atomizing circuit as described in claim 1, characterized in that, The humidifier atomization circuit also includes an atomization voltage monitoring circuit, which includes two voltage biasing circuits. The two ends of the first voltage biasing circuit are connected to the power ground (GND) and the output of the first switching transistor (Q1-1), respectively. The voltage divider tap of the first voltage biasing circuit is connected to the first atomization voltage monitoring pin (WavP_B) defined by the microcontroller (U1). The two ends of the second voltage biasing circuit are connected to the power ground (GND) and the output of the second switching transistor (Q1-2), respectively. The voltage divider tap of the second voltage biasing circuit is connected to the second atomization voltage monitoring pin (WavP_A) defined by the microcontroller (U1).

7. The humidifier atomizing circuit as described in claim 1, characterized in that, The humidifier atomization circuit also includes an atomization frequency tracking circuit, which includes a second resistor (R14) and a third capacitor (C20). One end of the second resistor (R14) is connected to the connection node between the input terminal of the first switching transistor (Q1-1) and the input terminal of the second switching transistor (Q1-2). The other end of the second resistor (R14) is grounded through the third capacitor (C20) and connected to the atomization frequency tracking pin (Ineb) defined by the microcontroller (U1).

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