Control method of water purifier

Abstract

The invention discloses a control method of a water purifier, and relates to the technical field of water purifiers. The water purifier comprises a water inlet waterway, a pure water waterway, a water outlet waterway and a filter element, a backflow waterway is arranged between the water inlet waterway and the pure water waterway, a booster pump is arranged in the water inlet waterway, and the backflow waterway is communicated with the inlet end of the booster pump. Determining first output power based on a target flow velocity corresponding to the outlet water temperature, and controlling the booster pump to operate according to the first output power so as to control the water purifier to enter a water production mode; and in the water production mode, water quality data fed back by the water inlet waterway and the pure water waterway respectively are obtained, the output power of the booster pump is adjusted based on the water quality data and the target flow speed, and the booster pump is controlled to continuously operate based on the adjusted output power. Therefore, the water purifier has the advantages of reducing noise, improving the quality of pure water and being more intelligent and reliable in work.

Description

Technical Field

[0001] The present application relates to the technical field of water purifiers, and in particular, to a control method for a water purifier. Background Art

[0002] Currently, the integrated water purifiers on the market include non-thermal tank instant water purifiers, which usually use a combination of a flow limiting valve and a flow meter to output water at a flow rate lower than the normal temperature flow rate according to the water outlet flow rate corresponding to the specified water outlet temperature. When the pure water production rate of the filter element is basically constant, a part of the pure water will flow back to the front end of the booster pump. When the water outlet flow rate is low and the pure water return volume is large, the excessive flow rate at the front end of the filter element will cause excessive pressure in front of the filter element membrane, resulting in an increase in the power of the entire machine and a large noise, which in turn shortens the life of the filter element and affects the user experience.

[0003] However, it is unreasonable to excessively pursue the reduction or increase of the pressure before the filter element membrane. When the pressure before the filter element membrane is too low, the pure water conversion will also decrease accordingly. When the salt permeation of the filter element is basically maintained constant, the lower pure water flow rate will lead to poor pure water quality or poor desalination rate performance; while increasing the pressure before the filter element membrane without limit will not only have the above-mentioned defects such as excessive noise, but also easily increase the salt permeation abnormally due to concentration polarization.

[0004] Therefore, when adjusting the pressure in front of the filter membrane, how to reasonably balance the pure water quality performance and power reduction and noise reduction has become a key research direction in the working scenario of the water purifier. Summary of the invention

[0005] The purpose of the present application is to provide a control method for a water purifier, which can improve the problem of excessive noise when the water purifier is working, and can make the pure water quality have better performance. Therefore, the present application has the advantages of reducing noise, improving the quality of pure water, and making the water purifier work more intelligently and reliably.

[0006] The embodiment of the present application is implemented as follows:

[0007] In a first aspect, an embodiment of the present application provides a control method for a water purifier, the water purifier comprising an inlet waterway, a pure water waterway, an outlet waterway and a filter element, a reflux waterway is provided between the inlet waterway and the pure water waterway, a booster pump is provided in the inlet waterway, and the reflux waterway is connected to an inlet end of the booster pump, the control method for the water purifier comprising: obtaining an outlet water temperature in a user instruction, determining a first output power based on a target flow rate corresponding to the outlet water temperature, and controlling the booster pump to operate according to the first output power to control the water purifier to enter a water production mode; in the water production mode, obtaining water quality data respectively fed back by the inlet waterway and the pure water waterway, adjusting the output power of the booster pump based on the water quality data and the target flow rate, and controlling the booster pump to operate continuously based on the adjusted output power.

[0008] In some embodiments, water quality data respectively fed back by the water inlet waterway and the pure water waterway are obtained, and the output power of the booster pump is adjusted based on the water quality data and the target flow rate, including: in the water production mode, determining whether the water quality data respectively fed back by the water inlet waterway and the pure water waterway meet preset conditions; if they meet the preset conditions, controlling the booster pump to operate at a first output power based on the target flow rate; if they do not meet the preset conditions, increasing the output power of the booster pump step by step from the first output power until the water quality data meets the preset conditions, using the current output power of the booster pump as the second output power, and controlling the booster pump to continuously operate at the second output power.

[0009] In some embodiments, during the adjustment process of the output power of the boost pump, when the output power reaches the rated output power of the boost pump, or when the pre-membrane pressure value of the filter element reaches a preset pressure threshold, the adjustment of the output power of the boost pump is stopped and the current water quality data is recorded.

[0010] In some embodiments, a pure water flow meter is provided in the pure water water circuit. In the water production mode, the control method of the water purifier also includes: updating the target pumping speed of the booster pump based on the PID algorithm, the target flow rate and the real-time pure water flow rate feedback from the pure water flow meter; and adjusting the target output power of the booster pump based on the latest target pumping speed.

[0011] In some embodiments, the target water pumping speed of the booster pump is updated based on the PID algorithm, the target flow rate and the real-time pure water flow rate fed back by the pure water flow meter, including: updating the pure water flow rate deviation based on the real-time pure water flow rate and the target flow rate; if the pure water flow rate deviation is less than a preset deviation threshold, outputting the target water pumping speed based on the integral control algorithm; if the pure water flow rate deviation is greater than or equal to the preset deviation threshold, outputting the target water pumping speed based on the full proportional control algorithm.

[0012] In some embodiments, based on the latest target pumping speed, the target output power of the boosting pump is adjusted, including: based on the target pumping speed, determining the pumping output power corresponding to the target pumping speed; if the pumping output power is less than the minimum starting power of the boosting pump, adjusting the target output power to the minimum starting power; if the pumping output power reaches the minimum starting power of the boosting pump, adjusting the target output power to the pumping output power.

[0013] In some embodiments, the control method of the water purifier also includes: determining the water production mode of the water purifier according to the outlet water temperature; when the water production mode is the instant water production mode, opening the reflux water circuit, determining the hot water outlet flow rate in the outlet water circuit according to the outlet water temperature, obtaining the preset reflux flow rate, and adding the hot water outlet flow rate and the reflux flow rate to obtain the target flow rate.

[0014] In some embodiments, the water purifier also includes an instant heating body, and the hot water outlet flow rate in the outlet water circuit is determined according to the outlet water temperature, including: calculating the hot water outlet flow rate based on the temperature difference between the raw water temperature in the inlet water circuit and the outlet water temperature, and the heating power of the instant heating body corresponding to the outlet water temperature.

[0015] In some embodiments, the control method of the water purifier also includes: when the water production mode is the normal temperature water production mode, the rated output power of the boost pump is used as the target output power, and pure water is output to the water outlet waterway at the normal temperature water production flow rate corresponding to the rated output power.

[0016] In some embodiments, the water purifier also includes a reflux flushing mode, and the control method of the water purifier also includes: a raw water quality sensor is provided in the water inlet circuit, and in the reflux flushing mode, the pure water reflux flushing time and / or the output power of the booster pump are adjusted based on the water quality data fed back by the raw water quality sensor; a water pressure sensor is provided in the water inlet circuit, and the water pressure sensor is provided on the inlet side of the booster pump. In the reflux flushing mode, the output power of the booster pump is adjusted based on the real-time water pressure detection value fed back by the water pressure sensor; the larger the real-time water pressure detection value, the smaller the output power of the booster pump.

[0017] The beneficial effects of this application compared with the prior art are:

[0018] The present application can improve the problem of excessive noise when the water purifier is working, and the pure water quality in the embodiments of the present application usually has good performance. The embodiments of the present application determine the first output power based on the target flow rate corresponding to the outlet water temperature in the user instruction, and control the operation of the booster pump according to the first output power, which can reasonably regulate the pumping speed required for the water purifier to prepare pure water, thereby reducing the pressure in front of the filter element membrane to reduce noise; the embodiments of the present application adjust the output power of the booster pump based on water quality data and target flow rate in the water production mode, which can improve the water quality of the pure water produced by the filter element or maintain it at a good level, so that the water purifier can take into account the requirements of noise reduction and good performance of pure water quality, and the water purifier works more intelligently and reliably, effectively improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 This is a schematic diagram of the water circuit structure of a water purifier shown in one embodiment of the present application;

[0021] Figure 2This is a flow chart of a method for controlling a water purifier according to an embodiment of the present application;

[0022] Figure 3 A flow chart of a method for controlling a water purifier according to an embodiment of the present application.

[0023] Figure markings: 1-water purifier; 110-water inlet waterway; 120-pure water waterway; 130-reflux waterway; 140-water outlet waterway; 141-normal temperature water outlet waterway; 142-instant hot water outlet waterway; 150-concentrated water discharge waterway; 201-filter element; 202-pre-filter element; 211-water inlet valve; 212-water outlet valve; 213-concentrated water valve; 221-boosting pump; 222-water pump; 231-check valve; 232-flow limiting valve; 241-raw water quality sensor; 242-pure water quality sensor; 251-first flow meter; 252-second flow meter; 260-water outlet faucet. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0025] Similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0026] The technical solution of the present application will be described clearly and completely below in conjunction with the accompanying drawings.

[0027] Please refer to Figure 1 , Figure 1 FIG. 1 is a schematic diagram of the water path structure of a water purifier 1 according to an embodiment of the present application. Figure 1 As shown, the present application provides a water purifier 1, which includes a water outlet faucet 260, an inlet waterway 110, a pure water waterway 120, an outlet waterway 140, a reflux waterway 130 and a concentrated water discharge waterway 150. Among them, one end of the pure water waterway 120 is connected to the inlet waterway 110 through a filter element 201, and the filter element is used to filter salts and impurities in the raw water to prepare pure water. The other end of the pure water waterway 120 is connected back to the inlet waterway 110 through the reflux waterway 130. One end of the outlet waterway 140 is connected to the pure water waterway 120, and the other end of the outlet waterway 140 is connected to the water outlet faucet 260.

[0028] The inlet waterway 110 may be provided with a pre-filter element 202, a raw water quality sensor 241, an inlet valve 211 and a booster pump 221 in sequence. Among them, the reconnection position of the reflux waterway 130 and the inlet waterway 110 is located on the water inlet side of the booster pump 221. The raw water quality sensor 241 may be provided on the outlet side of the pre-filter element 202; the raw water quality sensor 241 may also be provided on the water inlet side of the pre-filter element 202, and the raw water quality sensor 241 is used to detect the water quality detection value of the raw water that has not been filtered by the filter element 201. Furthermore, a check valve 231 is provided on the reflux waterway 130, and the check valve 231 is used to limit the flow direction of the pure water in the reflux waterway 130, so as to prevent the raw water in the inlet waterway 110 from entering the pure water waterway 120 or the outlet waterway 140 through the reflux waterway 130.

[0029] One end of the pure water circuit 120 is connected to the water inlet circuit 110 through the filter element 201, and the other end of the pure water circuit 120 is connected to the water outlet circuit 140 and the return circuit 130. The pure water circuit 120 may be provided with a pure water quality sensor 242 and a first flow meter 251, the first flow meter 251 is used to detect the pure water flow rate in the pure water circuit 120, and the pure water quality sensor 242 is used to detect the water quality detection value of the pure water obtained after filtering by the filter element 201. In the embodiment of the present application, the raw water quality sensor 241 and the pure water quality sensor 242 can both use TDS probes, and the water quality sensor is used to detect the water quality of the raw water or pure water in the water circuit where it is located, and the water quality is expressed by the TDS detection value.

[0030] The brine discharge waterway 150 is connected to the wastewater outlet of the filter element 201. The brine discharge waterway 150 is provided with a brine valve 213 for controlling the on-off of the brine discharge waterway 150. In some embodiments, the brine valve 213 may still have a small hole in the off state to allow a small amount of brine to be discharged.

[0031] The working modes of the water purifier 1 may include a standby mode, a water outlet mode, and a flushing mode. Among them, the water outlet mode may include a normal temperature water outlet mode and an instant hot water outlet mode. Correspondingly, the water outlet waterway 140 may include a normal temperature water outlet waterway 141 and an instant hot water outlet waterway 142, one end of each of the two water outlet waterways 140 is connected to the pure water waterway 120 and the reflux waterway 130, and the other end of each of the two water outlet waterways 140 is connected to the water outlet faucet 260. Among them, a water outlet valve 212 is provided on the normal temperature water outlet waterway 141, and a flow limiting valve 232, a second flow meter 252, and a pump 222 are provided on the instant hot water outlet waterway 142 in sequence, and the instant hot water outlet waterway 142 can heat pure water through the instant hot body, and pump the heated pure water to the water outlet faucet 260 through the pump 222.

[0032] See also Figure 2 , Figure 2FIG. 1 is a flow chart of a control method for a water purifier according to an embodiment of the present application. Figure 2 As shown, the embodiment of the present application provides a control method for a water purifier, which can be applied to the water purifier provided by any embodiment of the present application, and can also be applied to other water purifiers or water products. The control method for a water purifier includes the following steps S110 to S120.

[0033] S110: Obtain the outlet water temperature in the user instruction, determine the first output power based on the target flow rate corresponding to the outlet water temperature, and control the booster pump to operate according to the first output power to control the water purifier to enter the water production mode.

[0034] When using a water purifier, users usually choose to discharge water at room temperature or at a specified temperature. Therefore, the water purifier will carry the water outlet temperature in response to the user instruction generated by the user's click operation. Since the heating rate corresponding to the instant heating body in the water purifier fully heating the pure water to different temperatures within a unit time is different, the water outlet flow rate corresponding to different water outlet temperatures is different. Since the speed at which the filter element in the water purifier prepares pure water within a unit time depends on the reflux flow rate in the reflux waterway and the water outlet flow rate, when the reflux flow rate is fixed, the target flow rate corresponding to different water outlet temperatures may be different. The target flow rate refers to the pure water flow rate in the pure water waterway, and the target flow rate can also be understood as the speed at which the filter element prepares pure water. When the flow rate of the filter element to prepare pure water needs to be changed, the amount of water pumped by the booster pump within a unit time also needs to be changed accordingly to meet the pure water preparation requirements. Therefore, the output power of the booster pump also needs to change accordingly to meet the target flow rate of pure water preparation, that is, the water purifier should control the booster pump to operate according to the first output power corresponding to the target flow rate.

[0035] In this step, after receiving a user instruction carrying the outlet water temperature, the water purifier searches or calculates the target flow rate that the pure water in the pure water circuit should reach based on the outlet water temperature, and then calculates or searches the output power that can drive the booster pump to run and the amount of water pumped by the booster pump after running to meet the filter element's demand for preparing pure water at the target flow rate based on the target flow rate, and uses this power as the first output power to control the operation of the booster pump to control the booster pump to enter the water production mode. In an embodiment of the present application, the target flow rate and the first output power corresponding to the outlet water temperature can be pre-stored in the memory of the water purifier, and the water purifier can directly call it based on the outlet water temperature when searching for the target flow rate or the first output power; the water purifier can also use a calculation model for calculating the target flow rate and the first output power, and then input the outlet water temperature to directly obtain the target flow rate and the first output power output by the calculation model.

[0036] S120: In the water production mode, water quality data fed back from the water inlet circuit and the pure water circuit are obtained, the output power of the booster pump is adjusted based on the water quality data and the target flow rate, and the booster pump is controlled to continue to operate based on the adjusted output power.

[0037] The water production mode refers to the state in which the water purifier continuously prepares pure water through the filter element and discharges water according to the outlet water temperature. Water quality sensors for detecting water quality are provided in both the water inlet waterway and the pure water waterway. In the embodiment of the present application, the water purifier not only controls the booster pump to operate at the first output power according to the outlet water temperature, but also adjusts the output power of the booster pump based on the raw water quality data and the pure water quality data monitored in real time after the booster pump is running, so that the water quality performance of the pure water produced by the water purifier is maintained at a good level or improved, thereby taking into account the needs of noise reduction and good water quality performance.

[0038] In the above technical solution, the water purifier controls the booster pump to operate at the first output power corresponding to the target flow rate according to the outlet water temperature, which can reasonably reduce the pressure value in front of the filter element membrane. When the outlet water temperature is high, the water purifier cannot heat the high-flow pure water to this temperature in a short time. It is necessary to reduce the pure water flow rate in the instant hot water outlet waterway to fully heat the pure water. When the pure water flow rate in the return waterway is fixed, the speed of the filter element preparing pure water per unit time can also be appropriately reduced. Therefore, the booster pump usually does not need to operate at full power to pump water to the filter element, but only needs to operate at the first output power corresponding to the outlet water temperature or target flow rate. The reduction in the pressure in front of the filter element membrane reduces the noise volume when the water purifier prepares pure water. In water production mode, the water purifier further adjusts the output power of the booster pump based on water quality data and target flow rate, which can improve or maintain the water quality of pure water produced by the filter element. The pure water speed and water output speed of the water purifier are more accurate and reliable, thereby enabling the water purifier to take into account the needs of noise reduction and good performance of pure water quality. The water purifier works more intelligently and reliably, effectively improving the user experience.

[0039] See also Figure 3 , Figure 3 FIG. 1 is a flow chart of a control method for a water purifier according to an embodiment of the present application. Figure 3 As shown, the embodiment of the present application provides a control method for a water purifier, which can be applied to the water purifier provided by any embodiment of the present application, and can also be applied to other water purifiers or water products. The control method for a water purifier includes the following steps S201 to S240.

[0040] S201: When receiving a water extraction instruction from a user, obtain the outlet water temperature.

[0041] When a user uses a water purifier to take normal temperature water or hot water, he or she usually clicks or touches a button on the water purifier body to select the water outlet temperature, or manually enters the required water outlet temperature. The interactive module in the water purifier responds to the user's water extraction operation and can generate a user water extraction instruction carrying the water outlet temperature. When the control module (controller) in the water purifier receives the user water extraction instruction sent by the interactive module, it obtains the water outlet temperature carried in the user water extraction instruction.

[0042] S202: Determine the water production mode of the water purifier according to the outlet water temperature.

[0043] The water purifier may include a temperature sensor, which may be installed on the body of the water purifier or in the water circuit of the water purifier to detect the current air temperature or the temperature of the unheated raw water or pure water in the water circuit of the water purifier. The water making mode of the water purifier may include an instant hot water making mode and a normal temperature water making mode. The instant hot water making mode refers to a mode in which the water purifier filters the raw water to prepare pure water, and then allows the pure water to flow out of the water outlet faucet after being heated by the instant hot body in the instant hot water outlet water circuit; the normal temperature water making mode refers to a mode in which the water purifier filters the raw water to prepare pure water, and then allows the pure water to flow out of the water outlet faucet directly through the normal temperature water outlet water circuit. In this step, the water purifier can obtain the normal temperature water temperature through the temperature sensor, and then determine the water making mode of the water purifier according to the comparison result between the outlet water temperature and the normal temperature water temperature. If the outlet water temperature is higher than the normal temperature water temperature, the water making mode of the water purifier is the instant hot water making mode; if the outlet water temperature is not higher than the normal temperature water temperature, the water making mode of the water purifier is the normal temperature water making mode.

[0044] S210: In the instant hot water mode, the return water circuit is opened, a first output power is determined according to the outlet water temperature, and the booster pump is controlled to operate according to the first output power.

[0045] Taking the water flow rate of the water purifier as 800G as an example, when the outlet water temperature of the water purifier is at room temperature 25℃, and the booster pump is running at full power, the maximum speed that the filter element can reach in preparing pure water is the rated pure water flow rate (that is, the maximum flow rate that pure water in the pure water waterway can reach). Taking the rated pure water flow rate of 2000ml / min as an example, when the outlet water temperature of the water purifier is 100℃, the maximum flow rate that the instantaneous heating body in the instantaneous hot water outlet waterway can support is about 400ml / min. Without using the water production method of reducing pressure and power, the pure water flow rate in the return waterway when the booster pump is running at full power is as high as 1600ml / min.

[0046] When the outlet water temperature is high, the maximum outlet water flow rate that the instant hot water outlet waterway can support is limited. At this time, if the booster pump is still running at full power, it will cause the pure water flow rate in the reflux waterway to be too large, the pressure in front of the filter element membrane to increase, and the noise and the power of the whole machine to increase. Therefore, in the instant hot water outlet mode, the water purifier can appropriately reduce the output power of the booster pump, thereby reducing the speed at which the filter element prepares pure water and the reflux flow rate in the reflux waterway. In the instant hot water mode, the speed at which the filter element in the water purifier waterway prepares pure water is the target flow rate corresponding to the outlet water temperature. Generally, the higher the outlet water temperature, the lower the target flow rate, and the lower the first output power. In order to reduce the probability of empty jets and scalding users when the water purifier discharges hot water, the water purifier needs to adjust the pumping speed (output power) of the booster pump so that at least part of the pure water produced by the filter element can continue to flow back to the water inlet waterway through the reflux waterway at a fixed flow rate, so the reflux flow rate can be preset to a specified value.

[0047] Thus, the embodiment of the present application can determine the hot water outlet flow rate in the hot water outlet water path according to the outlet water temperature, and then calculate the pure water flow rate (i.e., the target flow rate) in the pure water water path according to the hot water outlet flow rate and the preset reflux flow rate, so as to further determine the first output power corresponding to the target flow rate. Step S210 includes sub-steps S211 to S213, and the specific contents are as follows.

[0048] S211: In the instant water heating mode, the return water circuit is opened.

[0049] In the embodiment of the present application, a reflux valve may be provided on the reflux waterway, and the reflux valve is used to control the on-off of the reflux waterway. Furthermore, the water purifier can open the reflux waterway by controlling the opening of the reflux valve. Alternatively, only a check valve may be provided on the reflux waterway, and the water purifier may control the booster pump to operate at an appropriate power according to the outlet water temperature, and then adjust the target flow rate of the filter element to prepare pure water, so that after part of the pure water flows into the instant hot water outlet waterway, part of the pure water can enter the water inlet waterway again through the reflux waterway.

[0050] In some embodiments, the water purifier can adjust the output power of the booster pump in advance according to the outlet water temperature, and then control the booster pump to discharge water at the first output power; in other embodiments, the water purifier can first control the booster pump to run at full power, and then determine the first output power based on the outlet water temperature, and adjust the output power of the booster pump from the rated output power to the first output power. In the instant hot water mode, the water purifier can first control the water inlet valve to open, control the booster pump to run at the first output power or full power, and then control the flow limiting valve and the water pump in the instant hot water outlet waterway to open, so as to achieve instant hot water outlet at a specified temperature.

[0051] S212: Determine the hot water outlet flow rate in the water outlet waterway according to the outlet water temperature, obtain a preset reflux flow rate, and add the hot water outlet flow rate and the reflux flow rate to obtain a target flow rate.

[0052] Part of the pure water obtained by filtering the filter element in the water purifier enters the instant hot water outlet waterway, and the other part flows into the water inlet waterway through the reflux waterway. Therefore, the target flow rate should be the cumulative value of the hot water outlet flow rate and the reflux flow rate in the instant hot water outlet waterway. The hot water outlet flow rate in the instant hot water outlet waterway depends on the outlet water temperature. In this step, the water purifier can find or calculate the hot water outlet flow rate in the instant hot water outlet waterway according to the outlet water temperature, and then obtain the pre-set reflux flow rate in the instant hot water mode, and then add the two together to get the target flow rate.

[0053] Specifically, the water purifier determines the hot water outlet flow rate in the outlet water path according to the outlet water temperature, including: calculating the hot water outlet flow rate based on the temperature difference between the raw water temperature in the inlet water path and the outlet water temperature, and the instant heating power corresponding to the outlet water temperature. For specific reference formulas, please refer to the following formulas (1)-(2).

[0054] Q=K×P×t=c×m×deltaT; (1)

[0055] m=(K×P×t) / (c×deltaT); (2)

[0056] Among them, Q is the energy consumed by the instant heating body to heat the pure water in the instant heating water outlet waterway to the outlet water temperature, in joule (J); P is the heating power of the instant heating body at the rated voltage AC220V, in W; t is the heating time of the instant heating body, usually with a unit time of 60s (1min); c is the specific heat capacity of water, in J / (kg·℃); m is the hot water outlet flow rate in the instant heating water outlet waterway, in ml / min; deltaT is the temperature difference between the unheated raw water temperature or pure water temperature and the outlet water temperature, in degrees Celsius (℃); K is the heating conversion efficiency of the instant heating body, which can be 0.85, 0.9, 0.95 and other values.

[0057] Further, the water purifier adds the preset reflux flow rate and the hot water outlet flow rate to obtain the target flow rate. The value of the reflux flow rate cannot be too small, that is, the target flow rate of the filter element to make pure water should be greater than the hot water outlet flow rate in the instant hot water outlet waterway, so as to reduce the risk of empty pumping in the instant hot water outlet waterway and the probability of jetting when the water outlet faucet is out of water; the value of the reflux flow rate is usually not too large, so as to reduce the pre-membrane pressure of the filter element, thereby achieving the purpose of energy saving and noise reduction. In the embodiment of the present application, the water purifier can adjust the set value of the reflux flow rate according to the outlet water temperature carried in the water extraction instruction, or the reflux flow rate can also be stored in the memory of the water purifier in the form of a fixed value, so that the water purifier can call the calculation when determining the target flow rate according to the hot water outlet temperature. In some embodiments, the reflux flow rate can be set to a fixed value, and the reflux flow rate value can be 600ml / min, 700ml / min, 800ml / min, 900ml / min, etc.

[0058] In the embodiment of the present application, different outlet water temperatures can correspond to different instant heating body heating powers and reflux flow rates, and accordingly, the target flow rates calculated by the water purifier according to the outlet water temperatures are also different. Please refer to the following table (1), which shows the parameters such as the instant heating body heating power and the target flow rate corresponding to different outlet water temperatures provided in an embodiment of the present application.

[0059] Table (1):

[0060]

[0061] S213: Determine a first output power according to the target flow rate, and control the boost pump to operate according to the first output power.

[0062] After the water purifier calculates or finds the target flow rate corresponding to the outlet water temperature according to the outlet water temperature, it can determine the first output power according to the target flow rate. The water purifier can calculate the first output power based on the target flow rate, or the water purifier can call the data relationship table stored in the memory to find the first output power corresponding to the target flow rate. Furthermore, the water purifier adjusts the output power of the boost pump to the first output power to control the boost pump to continuously pump water according to the first output power. Normally, the first output power is lower than the rated power, so that the noise of the water purifier is significantly reduced when making water.

[0063] S220: In the normal temperature water production mode, the preset output power is used as the target output power, and the booster pump is controlled to operate according to the preset output power.

[0064] In the normal temperature water production mode, the water purifier controls the water outlet valve to open, and a large amount of pure water can flow away through the normal temperature water outlet waterway and the water outlet faucet. The rear end pressure of the filter element can be effectively released, and the pressure in front of the membrane is generally low. Therefore, the water purifier can control the booster pump to operate at a higher preset output power to maximize the normal temperature water outlet flow rate of the water purifier and improve the performance of the whole machine. In the embodiment of the present application, the preset output power does not exceed the rated output power, and the filter element outputs pure water to the normal temperature water outlet waterway at the normal temperature water production flow rate corresponding to the preset output power.

[0065] In some embodiments, the water purifier can use the rated output power of the booster pump as the target output power, and the filter element outputs pure water to the normal temperature water outlet waterway at the normal temperature water production flow rate corresponding to the rated output power. The water purifier opens the water inlet valve and the water outlet valve, and controls the booster pump to start at full power. At the same time, the water purifier can also display the pure water production rate of the water purifier based on the first flow rate fed back by the first flow meter (the flow meter provided in the pure water waterway), thereby improving the user experience.

[0066] In an embodiment of the present application, when the water purifier controls the booster pump to operate at the target output power (first output power or preset output power) based on the outlet water temperature, the output power of the booster pump can also be adjusted adaptively in time according to the parameter information detected during the water production process. The following steps S230 to S240 provide two ways to adjust the output power of the booster pump, namely, adjustment based on the water quality detection situation and adjustment based on the actual detection flow rate. In an embodiment of the present application, the water purifier can be adjusted only according to the water quality situation (i.e., only step S230 is executed), can be adjusted only according to the actual flow rate (i.e., only step S240 is executed), or can be adjusted based on the water quality situation and the actual flow rate at the same time. In addition, when the water purifier adjusts the output power of the booster pump based on the water quality situation and the actual flow rate at the same time, the target output power re-determined based on the water quality situation can be used as the preferred adjustment target to maximize the water quality of the water purifier, thereby improving the user experience.

[0067] S230: Based on the water quality data and the target flow rate, the output power of the booster pump is adjusted, and the booster pump is controlled to continue to operate based on the adjusted output power.

[0068] Water quality refers to the water quality of the water purifier when the filter element filters the raw water to prepare pure water in the normal temperature water production mode or the instant hot water production mode. The water quality can be reflected in the form of desalination rate, or simply in the form of pure water TDS value. Water quality sensors can be installed on both the water inlet and pure water circuits of the water purifier to detect the quality of raw water and pure water respectively.

[0069] In some embodiments, the water purifier can obtain water quality data fed back by the water inlet circuit (raw water quality sensor in the water inlet circuit) and the pure water circuit (pure water quality sensor in the pure water circuit) respectively in the normal temperature water production mode or the instant water production mode, and then adjust the output power of the booster pump based on the water quality data and the target flow rate, and control the booster pump to continue to operate based on the adjusted output power. The specific details are as follows: the water purifier can determine whether the water quality data meets the preset conditions based on the raw water quality detection value and the pure water quality detection value received in real time. If the preset conditions are met, the water purifier controls the booster pump to continue to operate at the target output power. For example, in the instant water production mode, the water purifier controls the booster pump to continue to operate at the first output power based on the target flow rate. If the preset conditions are not met, the water purifier can increase or decrease the output power of the booster pump from the first output power step by step (usually increase it step by step) until the water quality data meets the preset conditions. Then, the water purifier uses the current output power of the booster pump when the water quality data meets the preset conditions as the second output power, that is, as the new target output power, to control the booster pump to continue to operate according to the second output power.

[0070] In an embodiment of the present application, the preset condition can be set as: the pure water TDS value is less than the preset TDS threshold, or the water quality level of the pure water meets the preset level, or the pollution level of the pure water or raw water is lower than the preset pollution level, etc.

[0071] To determine whether the water quality data meets the preset conditions, the desalination rate can be evaluated. For example, when both the raw water quality sensor and the pure water quality sensor are used to detect the TDS value, the desalination rate calculation formula is: Desalination rate = (TDS 原水 –TDS 纯水 ) / TDS 原水 When the desalination rate is less than the preset ratio (for example, 90%), the water purifier determines that the water quality data does not meet the preset conditions. In this case, the water purifier can gradually increase the output power of the booster pump to increase the pure water flow rate and the reflux flow rate in the pure water waterway, thereby trying to improve the filtration effect and improve the pure water quality performance.

[0072] To determine whether the water quality data meets the preset conditions, it can also be evaluated through the pure water quality detection value. For example, when the pure water quality sensor is used to detect the TDS value, the water purifier determines whether the pure water quality detection value is higher than the preset TDS threshold. If the pure water quality detection value is higher than the preset TDS threshold, the water purifier determines that the pure water quality does not meet the preset conditions. In this case, the water purifier can increase the output power of the booster pump step by step to increase the pure water flow rate and the reflux flow rate in the pure water waterway, and then try to improve the filtration effect and improve the pure water quality performance.

[0073] In some embodiments, if the method of adjusting the output power of the booster pump step by step cannot continue to improve the water quality of the pure water produced by the water purifier, or if the output power of the booster pump has been increased to the rated output power, if the desalination rate or water quality test value corresponding to the pure water produced in this case still does not meet the standard, it means that the filter element or the water quality sensor may be faulty. The water purifier can record the current pure water quality data and raw water quality data, and prompt the user after the water production is completed, so that the user can detect and repair.

[0074] S240: Based on the PID algorithm, the target flow rate and the real-time pure water flow rate fed back by the pure water flow meter, the target pumping speed of the booster pump is updated, and based on the latest target pumping speed, the target output power of the booster pump is adjusted.

[0075] Pure water flow meter refers to a flow meter installed in the pure water circuit to detect the flow rate of pure water produced by the filter element. Figure 1 As shown, the pure water flowmeter is the first flowmeter in the pure water water circuit. Specifically, in the normal temperature water making mode or the instant hot water making mode, the water purifier can obtain the real-time pure water flow rate in the pure water water circuit through the pure water flowmeter. Then, the water purifier can update the pure water flow rate deviation based on the real-time pure water flow rate and the target flow rate; if the pure water flow rate deviation is less than the preset deviation threshold, the water purifier outputs the target pumping speed based on the integral control algorithm; if the pure water flow rate deviation is greater than or equal to the preset deviation threshold, the water purifier outputs the target pumping speed based on the full proportional control algorithm. Finally, the water purifier adjusts the target output power of the booster pump based on the latest target pumping speed, and controls the booster pump to operate according to the new target output power. In some embodiments, when the water purifier calculates the target pumping speed and adjusts the target output power of the booster pump, the controller total interrupt can be turned off to prevent accidental interruptions from disrupting the control timing of the water purifier.

[0076] In the above technical solution, the water purifier introduces different algorithms based on whether the difference between the monitored real-time pure water flow rate and the target flow rate is less than the preset deviation threshold, so as to calculate the new target output power for controlling the operation of the boost pump, thereby more accurately and reliably controlling the boost pump to pump water and the filter element to make pure water.

[0077] In the embodiment of the present application, the output power of the boost pump should always reach the minimum starting power of the boost pump and should not exceed the rated output power of the boost pump. On this basis, a pressure sensor can also be provided in the water purifier to detect the pre-membrane pressure value of the filter element. When the pre-membrane pressure value of the filter element reaches the preset pressure threshold, the water purifier should stop adjusting the output power of the boost pump and record the current water quality data. In the process of the water purifier determining the target output power according to the updated target pumping speed of the boost pump, the water purifier uses the pumping output power corresponding to the target pumping speed as the target output power based on the target pumping speed. Among them, if the pumping output power is less than the minimum starting power of the boost pump, the water purifier adjusts the target output power to the minimum starting power; if the pumping output power reaches the minimum starting power of the boost pump, the water purifier adjusts the target output power to the pumping output power.

[0078] In addition to the water production mode, the water purifier can also adaptively adjust the output power of the booster pump in the backflow flushing mode to reduce the noise when flushing the filter element and save water, or improve the quality of filter flushing. There are many ways to adjust the output power of the booster pump in the backflow flushing mode, the specific details are as follows.

[0079] First, a raw water quality sensor may be provided in the water inlet circuit of the water purifier, and a pure water quality sensor may be provided in the pure water circuit of the water purifier. In the reflux flushing mode, the water purifier may adjust the pure water reflux flushing time and / or the output power of the booster pump based on the raw water quality data or pure water desalination rate fed back by the raw water quality sensor. In the above technical solution, the reflux flushing time and the output power of the booster pump are controlled according to the raw water quality detection value (raw water quality data), so that the water purifier can also reasonably reduce noise and fully flush during the flushing operation.

[0080] For example, the water purifier can adjust the pure water return flushing time according to the raw water TDS value fed back by the raw water quality sensor in real time. When the raw water TDS value is <100, the water purifier does not set the pure water return flushing time; when 250> the raw water TDS value is ≥100, the pure water return flushing time is set to 30s; when the raw water TDS is ≥250, the pure water return flushing time is set to 50s. In the pure water return flushing mode, the booster pump can run at full power, or it can adjust the output power to reduce the power operation in combination with the real-time feedback of the pure water quality detection value, thereby maintaining the good performance of the pure water quality while reducing the flushing noise of the water purifier.

[0081] Second, a water pressure sensor may be provided in the water inlet waterway of the water purifier, and the water pressure sensor may be provided on one side of the inlet end of the booster pump. In the reflux flushing mode, the water purifier may adjust the output power of the booster pump based on the real-time water pressure detection value fed back by the water pressure sensor. Among them, the larger the real-time water pressure detection value, the smaller the output power of the booster pump. In the embodiment of the present application, the water purifier adds a water pressure sensor between the water inlet valve and the booster pump, and controls the booster pump to reduce power operation according to the water pressure detection value collected by the water pressure sensor through a closed-loop feedback control algorithm, thereby improving the reliability of maintaining a constant water inlet pressure and achieving noise reduction.

[0082] Third, please refer to step S240. In the reflux flushing mode, the water purifier can adjust the output power of the booster pump in real time according to the real-time pure water flow rate feedback from the pure water flow meter and the preset target pure water flushing flow rate, so as to achieve closed-loop precise control of the pure water flushing flow rate, so as to realize the booster pump output power adjustment method similar to the water production mode.

[0083] Fourth, the water purifier can control the booster pump to operate according to the preset flushing output power, which is usually less than the rated output power; or, the water purifier can drive the booster pump to operate according to the preset flushing voltage, and the pulse signal corresponding to the flushing voltage is not the maximum duty cycle, so as to realize the direct pressure reduction control of the booster pump by the water purifier. The preset flushing output power and the preset flushing voltage are required to support the water purifier to complete the backflow flushing work between the minimum water inlet pressure and the maximum water inlet pressure (usually 0.1Mpa to 0.4Mpa).

[0084] The embodiment of the present application provides a computer-readable storage medium, which stores a computer program. The computer program can be executed by a main control chip or a controller to complete a control method of a water purifier.

[0085] If the function is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, and other media that can store program codes.

[0086] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A control method for a water purifier, the water purifier comprising an inlet waterway, a pure water waterway, an outlet waterway and a filter element, a return waterway is provided between the inlet waterway and the pure water waterway, a booster pump is provided in the inlet waterway, the return waterway is connected to the inlet end of the booster pump, characterized in that: The control method of the water purifier comprises: Obtaining the outlet water temperature in the user instruction, determining a first output power based on a target flow rate corresponding to the outlet water temperature, and controlling the booster pump to operate according to the first output power to control the water purifier to enter a water production mode; In the water production mode, water quality data fed back from the water inlet waterway and the pure water waterway are obtained, the output power of the booster pump is adjusted based on the water quality data and the target flow rate, and the booster pump is controlled to continue to operate based on the adjusted output power.

2. The control method of the water purifier according to claim 1, characterized in that: The step of adjusting the output power of the booster pump based on the water quality data and the target flow rate includes: In the water production mode, determining whether the water quality data fed back by the water inlet waterway and the pure water waterway meet the preset conditions; If the preset condition is met, controlling the booster pump to operate at the first output power based on the target flow rate; If the preset condition is not met, the output power of the boost pump is gradually increased from the first output power until the water quality data meets the preset condition, the current output power of the boost pump is used as the second output power, and the boost pump is controlled to continue running at the second output power.

3. The control method of the water purifier according to claim 2, characterized in that: During the adjustment process of the output power of the boost pump, when the output power reaches the rated output power of the boost pump, or when the pre-membrane pressure value of the filter element reaches a preset pressure threshold, the adjustment of the output power of the boost pump is stopped and the current water quality data is recorded.

4. The control method of the water purifier according to claim 1, characterized in that: A pure water flow meter is provided in the pure water waterway. In the water production mode, the control method of the water purifier further includes: Based on the PID algorithm, the target flow rate and the real-time pure water flow rate fed back by the pure water flow meter, updating the target pumping speed of the booster pump; Based on the latest target water pumping speed, the target output power of the boosting pump is adjusted.

5. The control method of the water purifier according to claim 4, characterized in that: The updating of the target pumping speed of the booster pump based on the PID algorithm, the target flow rate and the real-time pure water flow rate fed back by the pure water flow meter comprises: Based on the real-time pure water flow rate and the target flow rate, updating the pure water flow rate deviation; If the pure water flow rate deviation is less than a preset deviation threshold, outputting the target water pumping speed based on an integral control algorithm; If the pure water flow rate deviation is greater than or equal to the preset deviation threshold, the target water pumping speed is output based on a full proportional control algorithm.

6. The control method of the water purifier according to claim 4, characterized in that: The step of adjusting the target output power of the booster pump based on the latest target pumping speed includes: Based on the target water pumping speed, determining a water pumping output power corresponding to the target water pumping speed; If the water pump output power is less than the minimum starting power of the booster pump, adjusting the target output power to the minimum starting power; If the water pumping output power reaches the minimum starting power of the booster pump, the target output power is adjusted to the water pumping output power.

7. The control method of a water purifier according to any one of claims 1 to 6, characterized in that: The control method of the water purifier also includes: Determining the water production mode of the water purifier according to the outlet water temperature; When the water production mode is the instant water production mode, the reflux water circuit is opened, the hot water outlet flow rate in the outlet water circuit is determined according to the outlet water temperature, the preset reflux flow rate is obtained, the hot water outlet flow rate and the reflux flow rate are added together to obtain the target flow rate.

8. The control method of a water purifier according to claim 7, wherein the water purifier further comprises an instant heating element, characterized in that: The step of determining the hot water outlet flow rate in the water outlet waterway according to the outlet water temperature includes: The hot water outlet flow rate is calculated based on the temperature difference between the raw water temperature in the water inlet water path and the outlet water temperature, and the instant heating power corresponding to the outlet water temperature.

9. The control method of the water purifier according to claim 7, characterized in that: The control method of the water purifier also includes: When the water production mode is the normal temperature water production mode, the rated output power of the booster pump is used as the target output power, and pure water is output to the water outlet waterway at the normal temperature water production flow rate corresponding to the rated output power.

10. The control method of a water purifier according to any one of claims 1 to 6, characterized in that: The water purifier further includes a backflow flushing mode, and the control method of the water purifier further includes: A raw water quality sensor is provided in the water inlet water channel. In the backflow flushing mode, the pure water backflow flushing time and / or the output power of the booster pump are adjusted based on the water quality data fed back by the raw water quality sensor. A water pressure sensor is provided in the water inlet waterway, and the water pressure sensor is provided at one side of the inlet end of the booster pump. In the reflux flushing mode, the output power of the booster pump is adjusted based on the real-time water pressure detection value fed back by the water pressure sensor; the larger the real-time water pressure detection value, the smaller the output power of the booster pump.

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