Power drive system and control method for a hand-held suction iron adapted to work with a wide voltage

Abstract

The application discloses a power supply driving system and a control method of a handheld air suction ironer suitable for wide voltage operation, belongs to clothes ironing technology, and relates to the technical field of clothes ironing. The existing wide voltage scheme is difficult to be applied to the handheld air suction ironer. The power supply driving system comprises an input and phase detection unit, a rectification and voltage detection unit, a switching power supply unit, a main control unit, a fan driving unit, a heating control unit and a water pump driving unit. A circuit switching mechanism is arranged to select an electric heating tube for heating in a wide voltage range to match the actual voltage and realize the stability of the heating power. The rated voltage of the alternating electromagnetic pump is between 140V and 190V. In the low voltage interval or the high voltage interval, only the average driving power needs to be adjusted to keep the water supply flow relatively stable. Therefore, the whole handheld air suction ironer can work in the wide voltage range with the expected performance, can output steam with the expected flow and temperature, and can also adsorb clothes on the ironing panel to improve the ironing effect.

Description

Technical Field

[0001] This invention pertains to garment ironing technology, specifically relating to a power drive system and control method for a handheld vacuum iron that operates with a wide voltage range. It relies on setting the rated voltage of the AC electromagnetic pump between 140V and 190V, enabling the handheld vacuum iron to operate normally within an AC input range of 85V to 265V, outputting steam of the desired flow rate and temperature, and adsorbing the garment. Background Technology

[0002] Most handheld steam brushes or garment steamers currently on the market are only suitable for operation on a single voltage level. To meet the needs of global travel and multi-market sales, some wide-voltage steam generator solutions have emerged. These solutions mainly employ dual heating elements that automatically switch between each other via voltage detection to maintain a relatively consistent heating power. A wide-voltage steam generator disclosed in patent document CN211694813U is such existing technology.

[0003] However, existing wide-voltage solutions have the following drawbacks: They are significantly insufficient in the water supply stage. Commercially available AC electromagnetic pumps are mostly limited to 100–127V and 220–240V, lacking products suitable for a wider voltage range (85V to 265V). Using any fixed-specification electromagnetic pump at the other voltage level will result in a significant deviation of the flow rate from the target, or even pump damage. While dual-pump switching can solve the flow rate problem, it increases mechanical size, manufacturing costs, and assembly complexity, hindering the compact design of handheld products.

[0004] Furthermore, the applicant's patent documents CN122039406A, CN120989888A, CN224663232U, and CN224605298U all disclose handheld suction irons. Besides using a water pump to supply water and a vaporization device (heating tube) to vaporize the water into steam, these irons also use suction to draw the clothing onto the ironing surface to enhance the ironing effect. Compared to irons that only provide steam, these handheld suction irons also incorporate a suction fan in their electrical components. Existing technologies, such as the wide-voltage steam generator disclosed in patent document CN211694813U, are limited by the requirement to "ensure that the heating power or temperature is basically consistent," making them unsuitable for these handheld suction irons, mainly due to the following shortcomings: (1) Only heating consistency is addressed, without considering the changes in speed / suction of the high-speed DC fan under different input voltages. At the low-voltage end, if the motor is directly powered by the changing rectifier bus, the speed of the high-speed DC fan will drop significantly and the suction will be insufficient; at the high-voltage end, the high-speed DC fan may overspeed or overheat.

[0005] (2) Most water pumps are AC electromagnetic pumps, which are sensitive to voltage and frequency. The flow rate changes with the input voltage, resulting in unstable steam volume.

[0006] (3) There is a lack of coordinated closed-loop control for the two performance indicators, "steam volume" and "suction power," which are directly perceptible to users. Users experience significant differences when using the product in different countries / regions.

[0007] (4) The switching process, power distribution and protection logic are mostly designed for a single heating circuit and have not been optimized for multi-load coordination of handheld suction irons. Summary of the Invention

[0008] This invention addresses the shortcomings of existing wide-voltage steam generator solutions that are difficult to apply to handheld vacuum irons. It provides a power drive system and control method for handheld vacuum irons that can operate with a wide voltage range, aiming to maintain a basically constant steam output and suction power in the handheld vacuum iron within the full voltage range of AC85-265V.

[0009] To achieve the above objectives, the power drive system of the handheld vacuum iron of the present invention, which is adapted to wide voltage operation, includes: Input and phase detection unit, used to receive AC mains power and detect phase; The rectification and voltage detection unit is used to rectify AC mains power into high-voltage DC bus and detect the voltage. A switching power supply unit is used to draw power from the high-voltage DC bus and output low-voltage DC power. The main control unit is powered by the switching power supply unit and is used to acquire signals from the input and phase detection unit and the rectification and voltage detection unit. The fan drive unit includes a high-speed fan drive module directly powered by a high-voltage DC bus and a high-speed DC fan; A heating control unit includes at least two heating elements and a circuit switching mechanism. The circuit switching mechanism is used to select the heating element for heating within a wide voltage range to match the voltage range and achieve stable heating power. A water pump drive unit, including a pump drive circuit and an AC electromagnetic pump with a rated voltage between 140V and 190V; The main control unit is configured to: control the circuit switching of the heating control unit according to the voltage detection result, and adjust the average drive power of the AC electromagnetic pump according to the voltage detection result so that the water supply flow rate remains relatively stable within a wide voltage range.

[0010] In this system, a high-speed DC fan adheres the garment to the ironing panel during ironing. The electric heating element heats the garment, causing the vaporization device (or vaporization boiler) to vaporize the supplied water into steam. Appropriate water flow and heating power ensure the output of steam at the desired flow rate and temperature. Insufficient water flow and high heating power result in high-temperature steam, which may damage the garment. Conversely, insufficient water flow and low heating power fail to vaporize all the water, resulting in low-temperature steam mixed with water droplets, which does not achieve the desired ironing effect. The water pump is used to supply water at an appropriate flow rate. In other words, to guarantee the desired steam flow rate and temperature, the water pump must always deliver water at the desired flow rate within a wide voltage range, whether low or high voltage, and the electric heating element must always maintain a stable heating power to vaporize the supplied water into steam at the desired temperature, thus outputting steam at the desired flow rate and temperature for ironing.

[0011] This power drive system directly supplies power to the high-speed DC fan via a high-voltage DC bus. A circuit switching mechanism selects the heating element for heating within a wide voltage range to match the actual voltage (high or low voltage range), ensuring stable heating power. In particular, the AC electromagnetic pump's rated voltage is between 140V and 190V. Regardless of whether it's a low or high voltage range, adjusting the average drive power maintains a relatively stable water flow. This allows the handheld vacuum iron to operate with desired performance across a wide voltage range, outputting the desired steam flow and temperature while also adhering to the ironing panel to improve ironing results. The handheld vacuum iron maintains a relatively constant steam output and suction power within a wide voltage range of AC85-265V.

[0012] Preferably, the at least two heating elements include a first heating element and a second heating element, wherein the rated voltage of the first heating element is higher than that of the second heating element; when the AC mains voltage is in the high voltage range, only the first heating element operates; when the AC mains voltage is in the low voltage range, the first and second heating elements operate in parallel. The heating elements are considered as heating resistors, and the power formula for a purely resistive circuit is used. When the AC mains power is in the high voltage range, the desired heating power can be achieved by only the first heating element working. When the AC mains power is in the low voltage range, the first heating element and the second heating element work in parallel. The voltage decreases and the resistance decreases. By adjusting the resistance values ​​of the first heating element and the second heating element, the desired heating power can also be achieved.

[0013] Preferably, the first heating element is set to 240±20V / 1500±30W, and the second heating element is set to 120±10V / 1100±20W; when the AC mains power is in the high voltage range, only the first heating element works and outputs 1500±30W of power; when the AC mains power is in the low voltage range, the first heating element and the second heating element are connected in parallel to achieve a power of 1500±30W.

[0014] Preferably, the circuit switching mechanism is composed of a relay, with a switching threshold set between 160V and 180V and having hysteresis. That is, the relay is controlled to switch the circuit based on the voltage detection result, selecting the heating element for heating to match the voltage range and achieve stable heating power.

[0015] Preferably, the rated voltage of the AC electromagnetic pump is configured as 180V to adapt to AC mains voltage ranges, or as 150V to adapt to AC mains voltage ranges. That is, for different main sales markets of the handheld vacuum iron, the most suitable rated voltage is selected based on the dominant grid voltage: in the European market, the dominant grid voltage is 230V, and a customized voltage of approximately 180V is more advantageous; in the US and Japanese markets, the dominant grid voltage is 100–120V, and a customized voltage of approximately 150V is more advantageous. The advantage lies in the fact that the rated voltage is closer to the dominant grid voltage, thus allowing the AC electromagnetic pump to operate under near-rated conditions and achieve its performance. Furthermore, when the product is taken to an environment with a different dominant grid voltage due to travel or other factors, the rated voltage of the AC electromagnetic pump, being close to that dominant grid voltage, also allows the AC electromagnetic pump to operate normally.

[0016] Preferably, the rated voltage of the high-speed DC fan is 140VDC, which is suitable for wide voltage direct drive, and the operating speed range of the high-speed DC fan is 50,000 RPM to 100,000 RPM.

[0017] Preferably, the switching power supply unit includes a switching power supply module and an LDO step-down circuit. The switching power supply module outputs 15±3V DC power, and the LDO step-down circuit outputs approximately 5±1V DC power for use by the main control unit. The power drive system also includes a UI unit and a temperature control unit. The UI unit includes display LEDs and buttons, and the temperature control unit includes an NTC temperature sensor.

[0018] Preferably, the voltage detected by the rectifier and voltage detection unit is set to a low voltage range of 85V-170V, and the voltage detected by the rectifier and voltage detection unit is set to a high voltage range of 170V-265V.

[0019] The control method for a handheld vacuum iron adapted to wide voltage operation according to the present invention includes the following control means: (S1) Detect the input AC voltage or the bus voltage after the input AC voltage is rectified, and determine whether it is currently in a low voltage range or a high voltage range according to a preset threshold. (S2) Based on the voltage range, select a heating element from at least two heating elements for heating by switching the circuit to match the voltage range and achieve stable heating power; (S3) Drive a high-speed DC fan, which is directly powered by a high-voltage DC bus; (S4) Adjust the average drive power of the AC electromagnetic pump with a rated voltage between 140V and 190V according to the voltage detection results so that the AC electromagnetic pump can always maintain a relatively stable water supply flow rate in both low voltage and high voltage ranges.

[0020] This method also directly powers the high-speed DC fan via a high-voltage DC bus. A circuit switching mechanism selects the heating element for heating within a wide voltage range to match the high or low voltage range, ensuring stable heating power. Specifically, the AC electromagnetic pump's rated voltage is between 140V and 190V. Whether in a low or high voltage range, only the average drive power needs adjustment to maintain a relatively stable water flow. This allows the handheld vacuum iron to operate with the desired performance across a wide voltage range, outputting the desired steam flow and temperature while also adhering to the ironing panel to improve ironing results. The handheld vacuum iron maintains a relatively constant steam output and suction power across the entire AC 85-265V voltage range.

[0021] Preferably, the method for adjusting the average drive power of the AC electromagnetic pump based on the voltage detection results is as follows: when the AC mains voltage is in the low voltage range, the main control unit drives the AC electromagnetic pump continuously at full power; when the AC mains voltage is in the high voltage range, the main control unit drives the AC electromagnetic pump with full-cycle drop-out drive. This ensures that the AC electromagnetic pump maintains a relatively stable water supply flow rate regardless of whether the voltage range is low or high.

[0022] Preferably, the whole-cycle loss is synchronized by zero-crossing detection, and the switching is performed in units of a complete power frequency cycle, with the modulation cycle updated in units of 2 to 6 power frequency cycles.

[0023] Preferably, the main control unit outputs a PWM pulse width modulation signal to adjust the flow rate based on factors such as the target steam volume, the temperature of the vaporization device, and the water level, so that the flow rate matches the heating power and avoids overflow or dry burning.

[0024] Preferably, the thyristor adjusts the phase or zero-crossing based on the temperature feedback from the vaporization device detected by the NTC temperature sensor, so that the actual heating power of the electric heating tube meets the steam demand.

[0025] Preferably, the Boost voltage regulator circuit regulates the high voltage DC bus to a preset target (e.g., 310-340V), and the sensorless drive maintains the motor speed within the target range based on speed feedback or open-loop setting, thereby maintaining a basically constant suction force.

[0026] Preferably, when the voltage is extremely low and the Boost voltage regulator circuit is unable to regulate the high-voltage DC bus to the preset target, the speed setting of the high-speed DC fan is appropriately reduced or the high-speed DC fan is put into power priority mode.

[0027] Preferably, within the normal voltage range, priority is given to ensuring that both steam volume and suction power are close to the target values; when the voltage is close to the lower limit, priority is given to ensuring the basic steam volume and the suction power setting is appropriately reduced; when the voltage is close to the upper limit, power limiting protection is implemented; and the load is reduced before switching configurations to achieve a soft transition.

[0028] Preferably, the flow rate of the AC electromagnetic pump is set to 25±3g / min, the heating power of the electric heating tube is set to 1500±30W, and the suction force of the high-speed DC fan is set to 5.0KPa.

[0029] This invention directly powers a high-speed DC fan via a high-voltage DC bus. A circuit switching mechanism selects the heating element for heating within a wide voltage range to match the high or low voltage range, ensuring stable heating power. Specifically, the AC electromagnetic pump's rated voltage is between 140V and 190V. Regardless of whether it's a low or high voltage range, only the average drive power needs adjustment to maintain a relatively stable water flow. This allows the handheld suction iron to operate with desired performance across a wide voltage range, outputting the desired steam flow and temperature, maintaining stable steam output, and adhering to the ironing panel to improve ironing results. It achieves stable water supply, heating, and suction within a continuous wide voltage range, ensuring that the handheld suction iron maintains essentially constant steam output and suction power across the entire AC 85-265V voltage range. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the power drive system for the handheld vacuum iron that is adapted to wide voltage operation according to the present invention; Figure 2 This is a diagram of the heating control logic of the present invention; Figure 3 This is the control logic diagram for the average drive power of the AC electromagnetic pump of the present invention; Figure 4 This is a flowchart of the overall voltage adaptive control of the present invention; Explanation of the labels in the diagram: 100 Input and phase detection unit, 110 AC mains input module, 120 Mains phase detection circuit; 200 rectifier and voltage detection unit, 210 rectifier and filter module, 220 mains voltage detection circuit; 300 switching power supply unit, 310 switching power supply module, 320 step-down circuit; 400 main control unit; 500 fan drive unit, 510 high-speed fan drive module, 520 high-speed DC fan; 600 Heating control unit, 610 First heating element, 620 Second heating element, 630 First relay, 640 Second relay; 700 water pump drive unit, 710 pump drive circuit, 720 AC electromagnetic pump; 800 UI units, 810 LED displays, 820 buttons; 900 temperature control unit. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0032] The terms “comprising” and “having”, and any variations thereof, used in the specification and claims of this invention are intended to cover a non-exclusive inclusion, such as a method or product that includes a series of technical features, not necessarily limited to those technical features explicitly listed, but may also include other technical features that may be included in the method or product but not explicitly listed.

[0033] In the description of this invention, it should be understood that the technical features defined by terms such as "first" and "second" which have a sequential concept are only used to clearly describe the defined technical features and to clearly distinguish the defined technical features from other technical features, and do not represent that they are named in this way in actual implementation. Therefore, they should not be construed as limitations on this invention.

[0034] The present invention will now be described in detail with reference to specific embodiments and accompanying drawings.

[0035] Figure 1 A power drive system for a handheld vacuum iron that can operate with a wide voltage range is shown. The power drive system includes an input and phase detection unit 100, a rectification and voltage detection unit 200, a switching power supply unit 300, a main control unit 400, a fan drive unit 500, a heating control unit 600, and a water pump drive unit 700.

[0036] The input and phase detection unit 100 includes an AC mains input module 110 and a mains phase detection circuit 120, which are used to receive AC mains power and detect the phase.

[0037] The rectification and voltage detection unit 200 includes a rectification and filtering module 210 and an AC mains voltage detection circuit 220, which is used to rectify AC mains power into a high-voltage DC bus and detect the voltage.

[0038] The switching power supply unit 300 includes a switching power supply module 310 and a step-down module 320, which are used to draw power from the high-voltage DC bus and output low-voltage DC power.

[0039] The main control unit 400 is an MCU microcontroller unit, which is powered by the switching power supply unit 300 and is used to acquire signals from the input and phase detection unit 100 and the rectification and voltage detection unit 200.

[0040] The fan drive unit 500 consists of a high-speed fan drive module 510 and a high-speed DC fan 520, which are directly powered by a high-voltage DC bus.

[0041] The heating control unit 600 includes a first heating element 610, a second heating element 620, and a circuit switching mechanism. The circuit switching mechanism is used to select the heating element for heating within a wide voltage range to match the voltage range and achieve stable heating power.

[0042] The water pump drive unit 700 includes a pump drive circuit 710 and an AC electromagnetic pump 720 with a rated voltage between 140V and 190V.

[0043] The main control unit 400 is configured to: control the circuit switching of the heating control unit 600 according to the voltage detection result to select the heating tube for heating to match the voltage range and achieve stable heating power; and adjust the average driving power of the AC electromagnetic pump 720 according to the voltage detection result so that the water supply flow of the AC electromagnetic pump remains relatively stable within a wide voltage range.

[0044] The high-speed DC fan 520 adheres the garment to the ironing panel during ironing. The electric heating element vaporizes the supplied water into steam using a vaporization device (vaporization boiler). Appropriate water flow and heating power output the desired steam flow and temperature. Low water flow and high heating power result in high-temperature steam, which may damage clothing; high water flow and low heating power fail to vaporize all the water, resulting in low-temperature steam mixed with water droplets, which does not achieve the desired ironing effect. The water pump is used to input the appropriate flow of water. In other words, to ensure the desired steam flow and temperature, within a wide voltage range, whether low or high voltage, the AC electromagnetic pump must always deliver water at the desired flow rate, and the electric heating element must always vaporize the supplied water into steam at the desired temperature, thus outputting the desired steam flow and temperature for ironing.

[0045] This power drive system features a high-speed DC fan directly powered by a high-voltage DC bus. A circuit switching mechanism selects the heating element for heating within a wide voltage range to match the high or low voltage range, ensuring stable heating power. In particular, the AC electromagnetic pump has a rated voltage between 140V and 190V. Whether in a low or high voltage range, only the average drive power needs adjustment to maintain a relatively stable water flow. This allows the handheld vacuum iron to operate with desired performance across a wide voltage range, outputting the desired steam flow and temperature while also adhering to the ironing panel to improve ironing results. The handheld vacuum iron maintains a relatively constant steam output and suction power across the entire AC 85-265V voltage range.

[0046] In one embodiment, the rated voltage of the first heating element 610 is higher than the rated voltage of the second heating element 620; when the AC mains voltage is in the high voltage range, only the first heating element operates; when the AC mains voltage is in the low voltage range, the first and second heating elements operate in parallel. The heating elements are treated as heating resistors, and the power formula for a purely resistive circuit is used. When the AC mains voltage is in the high-voltage range, the first heating element alone can achieve the desired heating power. When the AC mains voltage is in the low-voltage range, the first and second heating elements operate in parallel. The voltage decreases, and the resistance decreases. By adjusting the resistance values ​​of the first and second heating elements, the desired heating power can still be achieved. This method eliminates the need to connect the two heating elements in series; selective switching and parallel connection are sufficient to maintain a relatively consistent heating power under both high and low voltage conditions. In other embodiments, switching methods such as series-parallel connection can also be used to achieve wide-voltage power matching.

[0047] In one embodiment, particularly suitable for ironing regular clothing, the first heating element 610 is set to 240±20V / 1500±30W, and the second heating element 620 is set to 120±10V / 1100±20W. When the AC mains power is in the high voltage range, only the first heating element works and outputs 1500±30W of power. When the AC mains power is in the low voltage range, the first heating element and the second heating element are connected in parallel to achieve a power of 1500±30W.

[0048] like Figure 1 As shown, the circuit switching mechanism consists of a first relay 630 and a second relay 640. The switching threshold is set between 160V and 180V and has hysteresis. That is, the relays are controlled to switch the circuit based on the voltage detection result, selecting the heating element for heating to match the voltage range and achieve stable heating power. Figure 2 As shown, in the high-voltage range, the first relay is closed and the second relay is open, so only the first heating element heats. In the low-voltage range, both the first and second relays are closed, and the first and second heating elements heat in parallel.

[0049] In a specific embodiment, the AC electromagnetic pump 720 is configured with a rated voltage of 180V to adapt to AC mains voltage ranges or 150V to adapt to AC mains voltage ranges. That is, for different main sales markets of the handheld vacuum iron, the most suitable rated voltage is selected based on the dominant grid voltage: for markets with a dominant grid voltage of 230V, a rated voltage of 180V is more advantageous; for markets with a dominant grid voltage of 100–120V, a rated voltage of 150V is more advantageous. The advantage lies in the fact that the rated voltage is closer to the dominant grid voltage, thus allowing the AC electromagnetic pump to operate under near-rated conditions and achieve its performance. Furthermore, when the product is transported to an environment with a different dominant grid voltage due to travel or other factors, the rated voltage of the AC electromagnetic pump remains close to that dominant grid voltage, enabling the AC electromagnetic pump to operate normally.

[0050] In one embodiment, the high-speed DC fan 520 has a rated voltage of 140VDC, is suitable for wide voltage direct drive, and operates at speeds ranging from 50,000 RPM to 100,000 RPM.

[0051] like Figure 1 As shown, the switching power supply unit 300 includes a switching power supply module 310 and an LDO step-down circuit 320. The switching power supply module 310 outputs 15±3V DC power, and the LDO step-down circuit 320 outputs approximately 5±1V DC power for use by the main control unit 400. The power drive system also includes a UI unit 800 and a temperature control unit 900. The UI unit 800 includes a display LED 810 and buttons 820, and the temperature control unit 900 includes an NTC temperature sensor. The buttons provide operation commands to the main control unit, and the NTC temperature sensor is used to detect the temperature of the vaporization device (vaporization boiler) in real time. When the temperature of the vaporization device (vaporization boiler) rises to a set threshold, the main control unit commands the power supply to the heating element to be stopped; when the temperature of the vaporization device (vaporization boiler) drops to the set threshold, the main control unit commands the power supply to the heating element to be restored.

[0052] In one embodiment, when the voltage detected by the rectifier and voltage detection unit 200 is 85V-170V, it is set as a low voltage range; when the voltage detected by the rectifier and voltage detection unit 200 is 170V-265V, it is set as a high voltage range.

[0053] Control methods for handheld vacuum irons that can operate with a wide voltage range include the following control measures: (S1) Detect the input AC voltage or the bus voltage after the input AC voltage is rectified, and determine whether it is currently in a low voltage range or a high voltage range according to a preset threshold. For example, if the preset threshold is 170V, a voltage range of 85V-170V is set as a low voltage range, and a voltage range of 170V-265V is set as a high voltage range.

[0054] (S2) Based on the voltage range (low voltage range or high voltage range), the heating element is selected from at least two heating elements for heating by circuit switching to match the voltage range and achieve stable heating power. Specifically, the rated voltage of the first heating element is higher than that of the second heating element. When the AC mains power is in the high voltage range, only the first heating element works. When the AC mains power is in the low voltage range, the first heating element and the second heating element work in parallel.

[0055] (S3) Drives a high-speed DC fan, which is directly powered by the high-voltage DC bus.

[0056] (S4) Adjust the average drive power of AC electromagnetic pump 720 with a rated voltage between 140V and 190V according to the voltage detection results so that the AC electromagnetic pump can always maintain a relatively stable water supply flow rate in both low voltage and high voltage ranges.

[0057] This method also directly powers the high-speed DC fan via a high-voltage DC bus. A circuit switching mechanism selects the heating element for heating within a wide voltage range to match the high or low voltage range, ensuring stable heating power. Specifically, the AC electromagnetic pump's rated voltage is between 140V and 190V. Regardless of whether it's a low or high voltage range, only the average drive power needs adjustment to maintain a relatively stable water flow. This allows the handheld vacuum iron to operate with the desired performance within a wide voltage range, outputting the desired steam flow and temperature while also adhering to the ironing panel to improve ironing results. The handheld vacuum iron maintains a relatively constant steam output and suction power within a wide voltage range of AC85-265V.

[0058] like Figure 3 As shown, the method for adjusting the average drive power of the AC electromagnetic pump based on the voltage detection results is as follows: when the AC mains voltage is in the low voltage range, the main control unit continuously drives the AC electromagnetic pump at full power; when the AC mains voltage is in the high voltage range, the main control unit drives the AC electromagnetic pump using full-cycle drop-out drive. This ensures that the AC electromagnetic pump maintains a relatively stable water supply flow regardless of whether the voltage range is low or high. More specifically, the full-cycle drop-out is synchronized through zero-crossing detection, with switching on and off in units of a complete power frequency cycle, and the modulation cycle using 2 to 6 power frequency cycles as the basic update unit.

[0059] like Figure 4 As shown, after the power is turned on and the handheld vacuum iron is started, the power supply voltage / bus voltage is detected, and then the voltage range is determined. When the actual voltage is in the high voltage range, only the first heating element heats, and the AC electromagnetic pump is driven with full-cycle drop-out drive to maintain stable water delivery (steam = 20g / min), heating of the heating element (heating power = 1500W), and stable fan speed (DC140V closed-loop control). When the actual voltage is in the low voltage range, both the first and second heating elements heat; the AC electromagnetic pump is driven continuously at full power to maintain stable water delivery (steam = 20g / min), heating of the heating element (heating power = 1500W), and stable fan speed (DC140V closed-loop control). Afterwards, the handheld vacuum iron continues to work stably, and closed-loop control is achieved by monitoring the working status.

[0060] In one embodiment, the main control unit outputs a PWM pulse width modulation signal to adjust the flow rate based on factors such as the target steam volume, the temperature of the vaporization device, and the water level, so that the flow rate matches the heating power and avoids overflow or dry burning.

[0061] In one embodiment, the thyristor adjusts the phase or zero-crossing based on the temperature feedback of the vaporization device detected by the NTC temperature sensor, so that the actual heating power of the heating element meets the steam demand.

[0062] In one embodiment, the high-voltage DC bus is regulated to a preset target (e.g., 310-340V) by the Boost voltage regulator circuit, and the sensorless drive maintains the motor speed within the target range based on speed feedback or open-loop setting, thereby maintaining a basically constant suction force.

[0063] In one embodiment, when the voltage is extremely low and the Boost voltage regulator circuit is unable to regulate the high-voltage DC bus to the preset target, the speed setting of the high-speed DC fan is appropriately reduced or the high-speed DC fan is put into power priority mode.

[0064] In one embodiment, within the normal voltage range, priority is given to ensuring that both steam volume and suction power are close to the target values; when the voltage is close to the lower limit, priority is given to ensuring the basic steam volume and the suction power setting is appropriately reduced; when the voltage is close to the upper limit, power limiting protection is implemented; and the load is reduced before switching configurations at the moment of switching to achieve a soft transition.

[0065] In one embodiment, the flow rate of the AC electromagnetic pump is set to 25±3 g / min, the heating power of the electric heating tube is set to 1500±30 W, and the suction force of the high-speed DC fan is set to 5.0 KPa.

[0066] Therefore, the following beneficial effects are achieved: 1. Within a wide voltage range of 85-265V, the steam output and suction power remain essentially constant, ensuring a consistent user experience.

[0067] 2. The heating, air intake, and water supply paths are decoupled, and each path can use the optimal topology and devices to improve efficiency and reliability.

[0068] 3. The fan adopts a fixed high-voltage rated + voltage stabilizing bus to avoid a significant drop in suction at the low-voltage end.

[0069] 4. The water pump is completely unaffected by AC voltage / frequency, and the flow rate is highly controllable.

[0070] 5. Facilitates product compliance with safety regulations and testing, and is suitable for handheld products with size and thermal management constraints.

[0071] The following table will be used to illustrate the various technical parameters.

[0072] Table 1: Power Architecture Parameters

[0073] Table 2: Detection and Main Control

[0074] Table 3: Heating Control Unit (Actually Confirmed)

[0075] Table 4: Water Pump Drive Unit (Core Innovation)

[0076] Table 5: Suction Motor Unit

[0077] Table 6: Human-Computer Interaction and Other Aspects

Claims

1. A power drive system for a handheld vacuum iron that operates with a wide voltage range, characterized in that: include: An input and phase detection unit (100) is used to receive AC mains power and detect the phase. A rectification and voltage detection unit (200) is used to rectify AC mains power into high voltage DC bus and detect the voltage. A switching power supply unit (300) is used to draw power from the high-voltage DC bus and output low-voltage DC power; The main control unit (400) is powered by the switching power supply unit and is used to acquire signals from the input and phase detection unit and the rectification and voltage detection unit; The fan drive unit (500) includes a high-speed fan drive module (510) directly powered by a high-voltage DC bus and a high-speed DC fan (520). The heating control unit (600) includes at least two heating elements and a circuit switching mechanism. The circuit switching mechanism is used to select the heating element for heating within a wide voltage range to match the voltage range and achieve stable heating power. The water pump drive unit (700) includes a pump drive circuit (710) and an AC electromagnetic pump (720) with a rated voltage between 140V and 190V. The main control unit is configured to: control the circuit switching of the heating control unit (600) according to the voltage detection result, and adjust the average driving power of the AC electromagnetic pump (720) according to the voltage detection result so that the water supply flow rate remains relatively stable within a wide voltage range.

2. The power drive system according to claim 1, characterized in that: The at least two heating elements include a first heating element (610) and a second heating element (620). The rated voltage of the first heating element (610) is higher than the rated voltage of the second heating element (620). When the AC mains power is in the high voltage range, only the first heating element works. When the AC mains power is in the low voltage range, the first heating element and the second heating element work in parallel.

3. The power drive system according to claim 2, characterized in that: The first heating element (610) is set to 240±20V / 1500±30W, and the second heating element (620) is set to 120±10V / 1100±20W. When the AC mains power is in the high voltage range, only the first heating element works and outputs 1500±30W of power. When the AC mains power is in the low voltage range, the first heating element and the second heating element are connected in parallel to achieve a power of 1500±30W.

4. The power drive system according to claim 1, characterized in that: The circuit switching mechanism is composed of relays, and the switching threshold is set between 160V and 180V and has hysteresis.

5. The power drive system according to claim 1, characterized in that: The AC electromagnetic pump (720) is configured with a rated voltage of 180V to adapt to AC mains power in the high voltage range or 150V to adapt to AC mains power in the low voltage range.

6. The power drive system according to claim 1, characterized in that: The rated voltage of the high-speed DC fan (520) is 140VDC, which is suitable for wide voltage direct drive. The operating speed range of the high-speed DC fan (520) is 50,000 RPM to 100,000 RPM.

7. The power drive system according to claim 1, characterized in that: The switching power supply unit (300) includes a switching power supply module (310) and an LDO step-down circuit (320). The switching power supply module (310) outputs 15±3V DC power, and the LDO step-down circuit (320) outputs approximately 5±1V DC power for use by the main control unit (400). The power drive system also includes a UI unit (800) and a temperature control unit (900). The UI unit (800) includes a display LED (810) and buttons (820), and the temperature control unit (900) includes an NTC temperature sensor.

8. The power drive system according to claim 1, characterized in that: When the voltage detected by the rectifier and voltage detection unit (200) is 85V-170V, it is set to the low voltage range; when the voltage detected by the rectifier and voltage detection unit (200) is 170V-265V, it is set to the high voltage range.

9. A control method for a handheld suction iron that adapts to a wide voltage range, characterized by: Including the following control measures: (S1) Detect the input AC voltage or the bus voltage after the input AC voltage is rectified, and determine whether it is currently in a low voltage range or a high voltage range according to a preset threshold. (S2) Based on the voltage range, select a heating element from at least two heating elements for heating by switching the circuit to match the voltage range and achieve stable heating power; (S3) Drive a high-speed DC fan, which is directly powered by a high-voltage DC bus; (S4) Adjust the average drive power of the AC electromagnetic pump with a rated voltage between 140V and 190V according to the voltage detection results so that the AC electromagnetic pump can always maintain a relatively stable water supply flow rate in both low voltage and high voltage ranges.

10. The control method according to claim 9, characterized in that: The method for adjusting the average drive power of the AC electromagnetic pump based on the voltage detection results is as follows: when the AC mains power is in the low voltage range, the main control unit uses full-power continuous drive for the AC electromagnetic pump; when the AC mains power is in the high voltage range, the main control unit uses full-cycle drop-out drive for the AC electromagnetic pump.

11. The control method according to claim 9, characterized in that: The entire cycle of wave drop is synchronized by zero-crossing detection, and the switching is performed in units of a complete power frequency cycle. The modulation cycle is updated in units of 2 to 6 power frequency cycles.

12. The control method according to any one of claims 9-11, characterized in that: The main control unit outputs a PWM pulse width adjustment signal to regulate the flow rate based on factors such as the target steam volume, the temperature of the vaporization device, and the water level, so that the flow rate matches the heating power and avoids overflow or dry burning.

13. The control method according to claim 9, characterized in that: The thyristor adjusts the phase or zero-crossing based on the temperature feedback from the vaporization device detected by the NTC temperature sensor, so that the actual heating power of the electric heating tube meets the steam demand.

14. The control method according to claim 9, characterized in that: The Boost voltage regulator circuit stabilizes the high-voltage DC bus to a preset target (such as 310-340V). The sensorless drive maintains the motor speed within the target range based on speed feedback or open-loop setting, thereby keeping the suction power basically constant.

15. The control method according to claim 13, characterized in that: When the voltage is extremely low, causing the Boost voltage regulator circuit to be unable to regulate the high-voltage DC bus to the preset target, the speed setting of the high-speed DC fan should be appropriately reduced or the high-speed DC fan should be put into power priority mode.

16. The control method according to claim 9, characterized in that: in Within the normal voltage range, priority is given to ensuring that both steam volume and suction power are close to the target values; when the voltage is close to the lower limit, priority is given to ensuring the basic steam volume and the suction power setting is appropriately reduced; when the voltage is close to the upper limit, power limiting protection is implemented; at the moment of switching, the load is reduced first and then the configuration is switched to achieve a soft transition.

17. The control method according to claim 9, characterized in that: The flow rate of the AC electromagnetic pump is set to 25±3g / min, the heating power of the electric heating element is set to 1500±30W, and the suction force of the high-speed DC fan is set to 5.0KPa.

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