Water purifier, Preheating control method, Electronic device, and Computer-readable storage medium

Abstract

The application discloses a water purifier, a preheating control method, an electronic device and a computer readable storage medium. The preheating control method comprises the following steps: obtaining a water use signal and a water temperature setting value; setting a corresponding cut-off preheating time value, a cut-off temperature rise speed value and a cut-off water temperature value according to a temperature rise value of heating the current water temperature value to the water temperature setting value; starting the preheating of the heating body; when one or more conditions of the preheating time of the heating body reaching the cut-off preheating time value, the temperature rise speed of the heating body exceeding the cut-off temperature rise speed value or the water temperature reaching the cut-off water temperature value are met, starting the booster pump and the water pump and starting to discharge water. The application not only controls simply, but also can more perfectly avoid the generation of the steam phenomenon in the preheating stage and the switching process from the preheating stage to the instant heating stage.

Description

Technical Field

[0001] This invention relates to the field of water purifiers, and particularly to an instant hot water purifier. Background Technology

[0002] Existing water purifiers that can heat water generally provide hot water in two ways. One is the hot water tank type, which uses an internal storage tank to pre-store and heat the filtered water. The other is the instantaneous hot water purifier, which heats the filtered water directly while it is being filtered.

[0003] The filtration system of an instant water purifier is typically the same as that of a regular water purifier, including a booster pump and filter cartridges. The difference lies in the heating system, which usually includes a heating element and a water pump. Because the water pressure is high after pressurization in the filtration system, a pressure-reducing device is used to reduce the pressure. A portion of the water returns to the filtration system, while the depressurized water enters the heating system for heating.

[0004] CN210103585U discloses an instant hot water purifier that uses a booster pump to push water into a pre-filter, a reverse osmosis filter, and a post-filter for filtration. Part of the filtered water returns to the booster pump for depressurization via a one-way return valve and a return solenoid valve, while the remainder enters the heating element for heating via a hot water discharge solenoid valve. CN219782281U discloses an instant hot water purifier that uses a self-priming pump to push water into filter elements for filtration. Part of the filtered water returns to the self-priming pump for depressurization via a three-way solenoid valve and a pressure relief pipe, while the remainder enters the instant heating pipe for heating via a water pump.

[0005] However, existing instant water purifiers, lacking a water tank, present a challenge in confirming water availability during heating. While a flow meter is added after the pressure reducing valve for flow detection, the flow meter itself requires time to detect flow. Furthermore, to accelerate heating, the heating element is typically preheated, meaning no water flows during preheating, and the flow meter receives no signal. Therefore, if the flow meter receives no signal during preheating, water will flow simultaneously after preheating. Initially, the flow meter cannot quickly report the flow rate due to its detection requirements. Consequently, if there is no water upstream or the water is rapidly vaporized, the pressure at the heating element's outlet will increase due to the pressure of the steam in the pipes during continuous heating. This results in little or no water entering the heating element, inevitably leading to rapid dry burning, causing steam leakage or burnout of the heating element. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome the defects of the existing instant water purifiers, which are prone to dry burning, steam spraying, and even burn-out of the heating element.

[0007] The present invention solves the above-mentioned technical problems through the following technical solution:

[0008] A preheating control method, the preheating control method comprising the following steps:

[0009] Obtain water usage signals and water temperature setpoints;

[0010] The corresponding preheating time, temperature rise rate, and water temperature are set based on the temperature rise value that heats the current water temperature to the set water temperature value.

[0011] Start the heating element to preheat;

[0012] When one or more of the following conditions are met: the preheating time of the heating element reaches the cut-off preheating time value, the temperature rise rate of the heating element exceeds the cut-off temperature rise rate value, or the water temperature reaches the cut-off water temperature value, the booster pump and water pump are started, and water is discharged.

[0013] In this solution, by monitoring preheating time, temperature rise rate, and water temperature to promptly stop preheating, steam injection and dry burning of the heating element can be effectively reduced or even avoided. Specifically, monitoring the cutoff values ​​for preheating time and water temperature minimizes the risk of water being heated to temperatures that generate excessive steam, especially when the water temperature setpoint is high. Furthermore, monitoring the cutoff value for temperature rise prevents the water from being heated too rapidly due to an abnormally fast temperature rise rate. By monitoring these three factors, steam injection during the preheating phase and the transition from preheating to instantaneous heating can be more effectively prevented.

[0014] Preferably, the step of setting the corresponding preheating time cutoff value, temperature rise cutoff value, and water temperature cutoff value based on the temperature rise value of heating the current water temperature to the set water temperature value includes:

[0015] Based on the preset data, obtain the cutoff preheating time, cutoff temperature rise rate, and cutoff water temperature corresponding to the current temperature rise value;

[0016] And / or calculate the estimated preheating time required to heat the water in the heating element to the set water temperature based on the temperature rise value, reduce the estimated preheating time value according to the preset reduction method to obtain the cut-off preheating time value, calculate the cut-off temperature rise rate value of the heating element required to heat the water flowing through the heating element to the set water temperature based on the temperature rise value, and reduce the set water temperature value according to the temperature rise value and the preset reduction method to obtain the cut-off water temperature value.

[0017] Therefore, by ending preheating when the preheating time limit is reached, the water in the heating element can be prevented from being heated to an excessively high temperature. By ending preheating when the temperature rise rate limit is reached, the flowing water at the outlet can be prevented from being heated and vaporized after preheating. By ending preheating when the water temperature limit is reached, operational margins can be provided for the heating control of subsequent water outlet heating elements. This is primarily to prevent the heating element from reaching an excessively high temperature during the preheating stage, which has a faster temperature rise than the immediate heating stage, thus avoiding steam ejection caused by insufficient time for the immediate heating stage heating element to cool down.

[0018] In this solution, one method is to obtain the cutoff preheating time, cutoff temperature rise rate, and cutoff water temperature based on the current situation. Another method is to select based on preset data; updating the preset data allows for more precise control in actual use.

[0019] Preferably, the step of reducing the expected preheating time value according to a preset reduction method to obtain the cutoff preheating time value includes:

[0020] The estimated preheating time value is reduced by one of the preset reduction ratio, reduction magnitude, or functional relationship to obtain the cut-off preheating time value;

[0021] And / or the step of reducing the water temperature setpoint according to the temperature rise value and the preset reduction method to obtain the cutoff water temperature value includes:

[0022] The temperature rise value is reduced according to one of the preset reduction ratio, reduction magnitude, or functional relationship to obtain a set difference value. The cutoff water temperature value is obtained by subtracting the set difference value from the water temperature set value.

[0023] The resulting values ​​for preheating cutoff time, temperature rise cutoff rate, and water temperature cutoff allow for more precise timing of the preheating end. This avoids excessively large values ​​that could lead to steam jetting, and also allows for the selection of values ​​that are closer to the actual situation by referencing the expected preheating time, water temperature setpoint, and temperature rise value, thus preventing the water from being underheated due to premature preheating.

[0024] Preferably, the step of calculating the cutoff temperature rise rate of the heating element required to heat the water flowing through the heating element to the set water temperature based on the temperature rise value includes:

[0025] Set the expected output flow rate of the water pump;

[0026] The expected temperature rise time of water flowing through the heating element is obtained based on the expected water flow rate of the water pump and the internal volume of the heating element.

[0027] The cutoff temperature rise rate is obtained by comparing the temperature rise value with the expected temperature rise time value.

[0028] Therefore, by obtaining the cutoff temperature rise rate value based on the expected operating conditions, it is possible to more accurately detect excessively rapid temperature rise of the heating element during actual operation, and to limit further preheating under accurate conditions. This ensures relatively sufficient preheating while preventing steam jetting that may occur at the beginning of water flow.

[0029] Preferably, the step of calculating the expected preheating time required to heat the water in the heating element to the set water temperature based on the temperature rise value includes:

[0030] The estimated preheating time is determined based on the power of the heating element, its internal volume, the specific heat capacity of water, and the temperature rise.

[0031] Therefore, the expected preheating time and preheating cutoff time are obtained based on the anticipated operating conditions, allowing for a more accurate determination of the actual preheating time of the heating element and enabling the limitation of further preheating under accurate conditions. This ensures relatively sufficient preheating while preventing steam jetting that occurs at the very beginning of water flow.

[0032] Preferably, after the step of starting the booster pump and water pump and beginning to discharge water, the method further includes:

[0033] The water flow rate in the heating pipe is detected, and heating is stopped when the water flow rate is less than a preset first flow rate reference value within a preset time.

[0034] Monitoring water flow can promptly detect steam injection, preventing damage caused by overheating of the heating element.

[0035] Preferably, the step of stopping the heating of the heating element may include, at the same time or after:

[0036] According to the preset reduction method, reduce one or more of the current cut-off preheating time value, cut-off temperature rise rate value, and cut-off water temperature value, and record the new cut-off preheating time value, cut-off temperature rise rate value, and cut-off water temperature value into the preset data.

[0037] Therefore, based on the steam injection phenomenon generated in the previous operation, the cutoff preheating time value, cutoff temperature rise rate value, and cutoff water temperature value record can be adjusted as a reference for the next operation to avoid the occurrence of steam injection phenomenon in the next operation.

[0038] Preferably, the step of reducing one or more of the current cutoff preheating time value, cutoff temperature rise rate value, and cutoff water temperature value according to a preset reduction method includes:

[0039] The current cutoff preheating time value, cutoff temperature rise rate value, and cutoff water temperature value are reduced according to one or more of the preset reduction ratio, reduction magnitude, and functional relationship.

[0040] Preferably, after the step of stopping the heating of the heating element, the method further includes:

[0041] The water flow rate in the heating pipe is detected. If the water flow rate exceeds the preset second flow rate reference value, the heating element is restarted to continue heating.

[0042] Therefore, by monitoring the water flow rate, the system can be activated when there is sufficient water flowing through the heating element after the steam injection phenomenon ends, ensuring water output during the immediate heating phase.

[0043] Preferably, after the step of starting the booster pump and water pump and starting to discharge water, the power of the heating element is controlled by a PID algorithm based on the water temperature setpoint and the detected outlet water temperature of the heating element, and the power of the heating element automatically increases as the outlet water temperature of the heating element decreases.

[0044] Therefore, after exiting the preheating stage, the PID control of the heating element can be seamlessly connected, thereby realizing the process from rapid preheating to rapid and precise temperature control and stable temperature.

[0045] Preferably, the step of starting the heating element to preheat includes:

[0046] The heating element is activated at its maximum power to begin heating.

[0047] This allows the heating element to preheat faster, while the preheating time cutoff value, temperature rise cutoff value, and water temperature cutoff value can prevent preheating runaway and steam injection.

[0048] A water purifier includes a filter, a booster pump, a pressure reducing device, a heating pipe, a water pump, and a heating element. The heating pipe is equipped with a flow sensor and a temperature sensor. The water purifier operates according to the preheating control method.

[0049] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor performs the preheating control method.

[0050] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the preheating control method.

[0051] The positive and progressive effects of this invention are that it is not only simple to control, but also can better avoid the occurrence of steam injection during the preheating stage and the process of switching from the preheating stage to the instantaneous heating stage. Attached Figure Description

[0052] Figure 1 This is a flowchart of a water purifier control method according to a first embodiment of the present invention.

[0053] Figure 2 This is a flowchart of a water purifier control method according to a second embodiment of the present invention.

[0054] Figure 3 This is a flowchart of a water purifier control method according to a third embodiment of the present invention.

[0055] Figure 4 This is a schematic diagram of the water circuit of a water purifier according to an embodiment of the present invention. Detailed Implementation

[0056] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments described herein.

[0057] like Figure 1 As shown, this invention discloses a preheating control method, which includes the following steps:

[0058] S100: Obtain water usage signal and water temperature setpoint;

[0059] S200: Set the corresponding preheating time cutoff value, temperature rise cutoff value, and water temperature cutoff value based on the temperature rise value that heats the current water temperature to the set water temperature value;

[0060] S300, Start the heating element preheating;

[0061] S400: When one or more of the following conditions are met: the preheating time of the heating element reaches the cutoff preheating time value, the temperature rise rate of the heating element exceeds the cutoff temperature rise rate value, or the water temperature reaches the cutoff water temperature value, the booster pump and water pump are started, and water is discharged.

[0062] Water temperature can be detected using various temperature detection devices, such as temperature sensors. Water temperature measurement can be performed, for example, by directly detecting the water temperature in the water path behind the heating element, or by remote sensing methods such as infrared sensors.

[0063] In step S100, the water temperature to be heated can be set to the set value by the user through various known methods such as adjusting buttons on the water purifier, remote control, or remote control via mobile device. A water usage signal can be obtained by the user through various known methods such as operating buttons on the water purifier, remote control, remote control via mobile device, or turning the faucet on and off.

[0064] In step S400, the booster pump can be any known pump suitable for various water purifiers, which achieves filtration by pressurizing water and passing it through the filter element. Pressure reduction of the filtered water can be achieved using various known pressure reduction methods in instant water purifiers, such as a pressure reducing valve reducing pressure while simultaneously returning a portion of the water to the booster pump or other locations.

[0065] In this embodiment, by timely stopping preheating based on preheating time, temperature rise rate, and water temperature, steam injection and dry burning of the heating element can be effectively reduced or even avoided. Specifically, monitoring the cutoff values ​​for preheating time and water temperature can minimize the risk of water being heated to temperatures that generate large amounts of steam, especially when the water temperature setpoint is high. Furthermore, monitoring the cutoff value for temperature rise rate can prevent the water from being heated too rapidly due to an abnormally fast temperature rise rate of the heating element. By monitoring these three factors, steam injection during the preheating stage and the transition from the preheating stage to the instantaneous heating stage can be more effectively prevented.

[0066] like Figure 2 As shown, in another preferred embodiment, the preheating control method may preferably include the following steps:

[0067] S100: Obtain water usage signal and water temperature setpoint;

[0068] S201. Calculate the estimated preheating time required to heat the water in the heating body to the set water temperature based on the temperature rise value, reduce the estimated preheating time value according to the preset reduction method to obtain the cut-off preheating time value, calculate the cut-off temperature rise rate value of the heating body required to heat the water flowing through the heating body to the set water temperature based on the temperature rise value, and reduce the set water temperature value according to the temperature rise value and the preset reduction method to obtain the cut-off water temperature value.

[0069] S202. Obtain the cut-off preheating time, cut-off temperature rise rate, and cut-off water temperature corresponding to the current temperature rise value based on the preset data.

[0070] S300, Start the heating element preheating;

[0071] S400: When one or more of the following conditions are met: the preheating time of the heating element reaches the cutoff preheating time value, the temperature rise rate of the heating element exceeds the cutoff temperature rise rate value, or the water temperature reaches the cutoff water temperature value, the booster pump and water pump are started, and water is discharged.

[0072] In step S201, water needs to be discharged immediately after the heating element is preheated, and the heating element cannot stop heating, otherwise there will be a period of cold water. The preheating time of the water in the heating element cannot be executed according to the calculation. During preheating, all parts of the heating element are heated simultaneously, so the water in the heating element will rise in temperature simultaneously. If it is preheated to a high temperature, such as 95°C, and water is discharged at this time while it is heating, the water at the original water inlet of the heating element has already reached a high temperature of 95°C during preheating, and it is still being heated by the heating element when it is discharged. Therefore, the temperature is likely to exceed 100°C, resulting in steam spraying. Once steam spraying occurs, a large amount of water vapor will form at the water outlet of the heating element, and the pressure at the water outlet of the heating element will increase, thereby causing the flow rate of the motor pump to decrease. The steam spraying phenomenon forms a positive feedback, and may even cause the heating element to burn out due to high temperature. Therefore, the preheating exit time condition, that is, the preheating cutoff time value, is set to be less than the expected preheating time value, such as half of the expected preheating time value.

[0073] In step S201, since the temperature rise is relatively rapid during preheating, temperature is also one of the judgment conditions. A certain amount of time needs to be reserved for temperature feedback control to prevent steam injection. For example, heating from 25℃ to the water temperature setpoint, such as 95℃, results in a temperature rise of 70℃. This temperature rise can be reduced from 70℃ to 35℃, and then the water temperature setpoint can be reduced based on this reduced 35℃ temperature rise, i.e., the water temperature setpoint of 95℃ is reduced to a cutoff water temperature of 60℃. By using the temperature rise method, a more consistent control effect can be obtained under different temperature setpoints and ambient water temperatures.

[0074] Steps S201 and S202 can be two independent steps, meaning they can be executed solely through step S201 or solely through step S202. When only step S202 is executed, the preset data can come from pre-set data. The preset data can be a relationship between the temperature rise value and the preheating time cutoff value, the temperature rise rate cutoff value, and the water temperature cutoff value. That is, for each temperature rise value, a corresponding preheating time cutoff value, temperature rise rate cutoff value, and water temperature cutoff value are specified. Alternatively, it can be a relationship between temperature rise value-related data and the preheating time cutoff value, temperature rise rate cutoff value, and water temperature cutoff value. For example, the water temperature setpoint and the current water temperature value can be considered as a whole and used as temperature rise-related data.

[0075] Steps S201 and S202 can also be implemented as a coordinated step. That is, one of steps S201 and S202 is selected for execution based on certain conditions. For example, during the initial run, step S201 is executed and stored as preset data, and in subsequent runs, the preset data is read and executed according to step S202.

[0076] Step S201 can refer to the cut-off preheating time value, cut-off temperature rise rate value, and cut-off water temperature value calculated in real time during the operation of the water purifier, or it can refer to the cut-off preheating time value, cut-off temperature rise rate value, and cut-off water temperature value calculated in the manner of step S201 before the water purifier is started.

[0077] By ending preheating in step S201 when the preheating time limit is reached, excessively high temperatures in the heating element can be avoided. Ending preheating when the temperature rise rate limit is reached prevents the flowing water at the outlet from vaporizing after preheating. Ending preheating when the water temperature limit is reached provides operational margin for the heating control of subsequent outlet heating elements. This primarily aims to prevent steam ejection caused by the heating element reaching excessively high temperatures during the preheating stage (which has a faster temperature rise than the immediate heating stage) and not having sufficient time to cool down during the immediate heating stage.

[0078] In this embodiment, one method is to obtain the cutoff preheating time, cutoff temperature rise rate, and cutoff water temperature based on the current situation. Another method is to select based on preset data; updating the preset data allows for more precise control in actual use.

[0079] In a further preferred embodiment, the step S201 of reducing the expected preheating time value according to a preset reduction method to obtain the cutoff preheating time value includes: reducing the expected preheating time value according to one of a preset reduction ratio, reduction magnitude, or functional relationship to obtain the cutoff preheating time value; and / or the step of reducing the water temperature setpoint according to the temperature rise value and the preset reduction method to obtain the cutoff water temperature value includes: reducing the temperature rise value according to one of a preset reduction ratio, reduction magnitude, or functional relationship to obtain a preset difference value, and subtracting the preset difference value from the water temperature setpoint to obtain the cutoff water temperature value.

[0080] The resulting values ​​for preheating cutoff time, temperature rise cutoff rate, and water temperature cutoff allow for more precise timing of the preheating end. This avoids excessively large values ​​that could lead to steam jetting, and also allows for the selection of values ​​that are closer to the actual situation by referencing the expected preheating time, water temperature setpoint, and temperature rise value, thus preventing the water from being underheated due to premature preheating.

[0081] In a further preferred embodiment, step S201, which involves calculating the cutoff temperature rise rate of the heating element required to heat the water flowing through it to a set water temperature, includes:

[0082] Set the expected output flow rate of the water pump;

[0083] The expected temperature rise time of water flowing through the heating element is obtained based on the expected water flow rate of the water pump and the internal volume of the heating element.

[0084] The cutoff temperature rise rate is obtained by comparing the temperature rise value with the expected temperature rise time value.

[0085] In the above steps, for example, the expected outflow rate is set to F = 0.428 L / min, and the internal volume of the heating element is V = 25 ml. Therefore, the expected temperature rise time for the water flowing through the heating element is t = V * 60 / F = 25 * 60 / 428 = 3.5 s. The temperature rise value is calculated as ΔT = 70 ℃ from 25 ℃ to 95 ℃. Thus, the temperature rise per second, i.e., the cutoff temperature rise rate, can be calculated as ΔT / t = 70 / 3.5 = 20 ℃ / s.

[0086] Therefore, by obtaining the cutoff temperature rise rate value based on the expected operating conditions, it is possible to more accurately detect excessively rapid temperature rise of the heating element during actual operation, and to limit further preheating under accurate conditions. This ensures relatively sufficient preheating while preventing steam jetting that may occur at the beginning of water flow.

[0087] Further, the step S201, which involves calculating the estimated preheating time required to heat the water in the heating element to the set water temperature based on the temperature rise, includes: obtaining the estimated preheating time based on the power of the heating element, the internal volume of the heating element, the specific heat capacity of water, and the temperature rise. The estimated preheating time can be calculated, for example, according to a physical theorem: P*t=C*V△T. Where P is the power of the heating element, t is the estimated preheating time, C is the specific heat capacity of water (taken as 4200), V is the internal volume of the heating element, and △T is the temperature rise, i.e., the deviation between the set water temperature and the current water temperature. For example: a 2100W heating element, a current water temperature of 25℃, a set water temperature of 95℃, and an internal volume V of 25ml, the preheating time is calculated as: t=C*V△T / P=4200*0.025*70 / 2100=3.5s.

[0088] Therefore, the expected preheating time and preheating cutoff time are obtained based on the anticipated operating conditions, allowing for a more accurate determination of the actual preheating time of the heating element and enabling the limitation of further preheating under accurate conditions. This ensures relatively sufficient preheating while preventing steam jetting that occurs at the very beginning of water flow.

[0089] like Figure 3 As shown, this invention discloses a preheating control method, which includes the following steps:

[0090] S100: Obtain water usage signal and water temperature setpoint;

[0091] S202. Obtain the cut-off preheating time, cut-off temperature rise rate, and cut-off water temperature corresponding to the current temperature rise value based on the preset data.

[0092] S300, Start the heating element preheating;

[0093] S400: When one or more of the following conditions are met: the preheating time of the heating element reaches the cut-off preheating time value, the temperature rise rate of the heating element exceeds the cut-off temperature rise rate value, or the water temperature reaches the cut-off water temperature value, the booster pump and the water pump are started, and water is discharged outward.

[0094] S500: Detect the water flow rate of the heating pipeline, and stop heating the heating element when the water flow rate is less than the preset first flow rate reference value within a preset time.

[0095] S600: Reduce one or more of the current cut-off preheating time value, cut-off temperature rise rate value, and cut-off water temperature value according to the preset reduction method, and record the new cut-off preheating time value, cut-off temperature rise rate value, and cut-off water temperature value into the preset data.

[0096] In this embodiment, the execution of step S500 can promptly detect the occurrence of steam jetting by monitoring the water flow rate, thus preventing damage to the heating element due to overheating. For example, when hot water begins to be dispensed immediately after preheating, if no data is detected within a preset time (e.g., the time it takes for 1 / 3 of the water flow to pass through the heating element, e.g., 1.2 seconds) via a flow meter, it indicates that there is no water at the front end, and heating is immediately stopped. Of course, step S500 can also be applied as needed. Figure 1 and Figure 2 In the embodiment shown, the first flow rate reference value can be 0, or other minute flow rate values ​​that may be generated when steam injection occurs.

[0097] Step S600 can be executed simultaneously with or after stopping the heating element in step S500. However, overall, step S500 is executed first; it's just a matter of whether S600 is started immediately after determining that the flow rate is less than the preset first reference value, or whether step S500 is executed completely before step S600. In step S600, based on the steam injection phenomenon observed in the previous run, the preheating time cutoff value, temperature rise cutoff rate value, and water temperature cutoff value can be adjusted as a reference for the next run to prevent the recurrence of steam injection. Of course, step S600 can also be used as needed. Figure 1 and Figure 2 The implementation method shown.

[0098] The step in S600 of reducing one or more of the current cutoff preheating time value, cutoff temperature rise rate value, and cutoff water temperature value according to a preset reduction method includes: reducing one or more of the current cutoff preheating time value, cutoff temperature rise rate value, and cutoff water temperature value according to a preset reduction ratio, reduction magnitude, or functional relationship. For example, in S202, the preset cutoff preheating time value is 3.5s, the cutoff temperature rise rate value is 20℃, and the cutoff water temperature value is 60℃. Once the condition in S500 is triggered, new preset data can be obtained by reduction, such as a new cutoff preheating time value of 3.0s, a new cutoff temperature rise rate value of 18℃, and a new cutoff water temperature value of 55℃. Then, the new preset data is stored as the basis for the next execution of step S202.

[0099] In some implementations, after S500 stops heating, the user can be notified via an alarm or other means, allowing them to restart the heating element after a certain period. A more preferred approach is to further include, after step S500, detecting the water flow rate in the heating pipe and restarting the heating element when the flow rate exceeds a preset second flow rate reference value. By monitoring the water flow rate and comparing it with the second flow rate reference value, the heating element can be restarted once sufficient water flows through it after the steam jetting phenomenon has ended, ensuring water output during the immediate heating phase, thus eliminating the need for the user to re-operate.

[0100] exist Figures 1-3 In this embodiment, step S300 can be performed using an existing control method for the heating element, or preferably, the heating element can be started at its maximum power. This allows for faster preheating of the heating element, and by monitoring the preheating time cutoff value, the temperature rise rate cutoff value, and the water temperature cutoff value, preheating runaway and steam injection can be avoided.

[0101] exist Figures 1-3 In this embodiment, the instant heating after step S400 can be performed by controlling the heating element, water pump, and booster pump in the existing instant heating method. Alternatively, the power of the heating element can be controlled by a PID algorithm based on the water temperature setpoint and the detected outlet water temperature of the heating element. The power of the heating element automatically increases as the outlet water temperature decreases. This allows for seamless transition from PID control of the heating element after exiting the preheating stage, thus achieving a process from rapid preheating to rapid, precise temperature control and stable temperature.

[0102] The power of the heating element is further optimized and controlled by a PID algorithm based on the water temperature setpoint and the detected heated water temperature. The power of the heating element automatically increases as the heated water temperature decreases. For example, P0 = U(t) = Kp2*e(t) + Ki2*Σe(t) + Kd2*(e(t) - e(t-1)), where e(t) is the current error e(t) = ΔT = heated water temperature – water temperature setpoint, e(t-1) is the previous error, and Kp2, Ki2, and Kd2 are all PID system parameters that can be set empirically according to the situation. The output data is the power.

[0103] A further preferred water pump can be an electric motor pump. Furthermore, the pump's power is controlled by a PID algorithm based on the pump's rated flow rate and the detected flow rate in the heating pipe. For example, an incremental PID algorithm can be used, with the formula: ΔU1(t)=Kp1*(e(t)-e(t-1))+Ki1*e(t)+Kd1*(e(t)–2*e(t-1)+e(t-2)). U1(t) is the water flow rate that needs to be adjusted, e (t) represents the current flow deviation, i.e., the standard deviation under the current voltage of the water pump. The deviation between the constant flow rate and the actual flow rate of the heating pipeline measured by the flow meter is caused by throttling after pressure reduction. e(t-1) is the previous flow rate deviation, and e(t-2) is the flow rate deviation two weeks prior. Kp1, Ki1, and Kd1 are the coefficients of the PID controller. Based on experience and actual adjustment results, the values ​​of Kp, Ki, and Kd coefficients can be confirmed. After calculating U1(t), the flow rate is adjusted by adjusting the voltage of the water pump.

[0104] like Figure 4 As shown, this invention also discloses a water purifier, including a filtration device (filter cartridges 12 and 13), a booster pump 11, a pressure reducing device (pressure reducing valve 25), a heating pipe 20, a water pump 21, and a heating element 22. The heating pipe 20 is equipped with a flow sensor 24 and two temperature sensors 23 before and after the heating element 22. During the preheating stage, the current water temperature can be detected by the two temperature sensors 23 before and after the heating element 22. During the instant heating stage, the heated water temperature is obtained by the temperature sensor 23 at the outlet end (rear end) of the heating element 22, and the water temperature before heating is obtained by the temperature sensor 23 at the inlet end of the heating element 22. The water purifier operates according to the aforementioned preheating control method. The heating pipe is controlled by a solenoid valve 26, and another ambient temperature water path is controlled by another solenoid valve 26. The water purifier also includes a wastewater valve 14 and an ultraviolet disinfection device 15. After the booster pump 11 pressurizes the water, a portion of it passes through filters 13 and 12 and is depressurized by pressure reducing valve 25 before entering the heating chamber, while the other portion flows back.

[0105] The present invention also discloses an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor performs the water purifier control method.

[0106] The present invention also discloses a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the water purifier control method.

[0107] This invention is not only simple to control, but also can better avoid the occurrence of steam injection during the preheating stage and the process of switching from the preheating stage to the instantaneous heating stage.

[0108] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A preheating control method, characterized in that, The preheating control method includes the following steps: Obtain water usage signals and water temperature setpoints; The preheating time cutoff value, temperature rise cutoff value, and water temperature cutoff value are set according to the temperature rise value that heats the current water temperature to the set water temperature value. Specifically, this includes: obtaining the preheating time cutoff value, temperature rise cutoff value, and water temperature cutoff value corresponding to the current temperature rise value based on preset data. This includes: calculating the expected preheating time value required to heat the water in the heating body to the set water temperature value based on the temperature rise value; reducing the expected preheating time value according to a preset reduction method to obtain the preheating time cutoff value; reducing the set water temperature value based on the temperature rise value and the preset reduction method to obtain the water temperature cutoff value; and calculating the temperature rise cutoff value of the heating body required to heat the water flowing through the heating body to the set water temperature value based on the temperature rise value. Start the heating element to preheat; When one or more of the following conditions are met: the preheating time of the heating element reaches the cut-off preheating time value, the temperature rise rate of the heating element exceeds the cut-off temperature rise rate value, or the water temperature reaches the cut-off water temperature value, the booster pump and water pump are started, and water begins to flow out. The system detects the water flow rate in the heating pipe and stops heating when the water flow rate falls below a preset first reference value within a preset time period. The process of stopping the heating element, either simultaneously or afterward, includes: reducing one or more of the current cut-off preheating time value, cut-off temperature rise rate value, and cut-off water temperature value according to a preset reduction method, and recording the new cut-off preheating time value, cut-off temperature rise rate value, and cut-off water temperature value into preset data.

2. The preheating control method as described in claim 1, characterized in that, The step of reducing the expected preheating time value according to a preset reduction method to obtain the cutoff preheating time value includes: The expected preheating time value is reduced by one of the preset reduction ratio, reduction magnitude, or functional relationship to obtain the cut-off preheating time value; And / or the step of reducing the water temperature setpoint according to the temperature rise value and the preset reduction method to obtain the cutoff water temperature value includes: The temperature rise value is reduced according to one of the preset reduction ratio, reduction magnitude, or functional relationship to obtain a set difference value. The cutoff water temperature value is obtained by subtracting the set difference value from the water temperature set value.

3. The preheating control method as described in claim 1, characterized in that, The step of calculating the cutoff temperature rise rate of the heating element required to heat the water flowing through it to a set water temperature based on the temperature rise value includes: Set the expected output flow rate of the water pump; The expected temperature rise time of water flowing through the heating element is obtained based on the expected water flow rate of the water pump and the internal volume of the heating element. The cutoff temperature rise rate is obtained by comparing the temperature rise value with the expected temperature rise time value.

4. The preheating control method as described in claim 1, characterized in that, The step of calculating the estimated preheating time required to heat the water in the heating element to the set water temperature based on the temperature rise value includes: The estimated preheating time is determined based on the power of the heating element, its internal volume, the specific heat capacity of water, and the temperature rise.

5. The preheating control method as described in claim 1, characterized in that, The step of reducing one or more of the current cutoff preheating time value, cutoff temperature rise rate value, and cutoff water temperature value according to a preset reduction method includes: The current cutoff preheating time value, cutoff temperature rise rate value, and cutoff water temperature value are reduced according to one or more of the preset reduction ratio, reduction magnitude, and functional relationship.

6. The preheating control method as described in claim 1, characterized in that, Following the step of stopping the heating element, the following is also included: The water flow rate in the heating pipe is detected. If the water flow rate exceeds the preset second flow rate reference value, the heating element is restarted to continue heating.

7. The preheating control method according to any one of claims 1-6, characterized in that, After the steps of starting the booster pump and water pump and starting to discharge water are completed, the power of the heating element is controlled by a PID algorithm based on the water temperature setpoint and the detected outlet water temperature of the heating element. The power of the heating element automatically increases as the outlet water temperature of the heating element decreases.

8. The preheating control method according to any one of claims 1-6, characterized in that, The step of starting the heating element preheating includes: The heating element is activated at its maximum power to begin heating.

9. A water purifier, characterized in that, The water purifier includes a filter, a booster pump, a pressure reducing device, a heating pipe, a water pump, and a heating element. The heating pipe is equipped with a flow sensor and a temperature sensor. The water purifier operates according to the preheating control method described in any one of claims 1-8.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, The processor executes the preheating control method as described in any one of claims 1-8.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the preheating control method as described in any one of claims 1-8.

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