Water purification system and control method thereof

Abstract

The invention belongs to the technical field of water purification, and particularly discloses a water purification system and a control method of the water purification system. The water purification system comprises a booster pump, a first filtering device, a second filtering device and a bypass pipe, the bypass pipe and the second filtering device are arranged in parallel, the first filtering device is provided with a first water inlet, a first pure water outlet and a first concentrated water port, and the second filtering device is provided with a second water inlet, a second pure water outlet and a second concentrated water port; the first water inlet is communicated with the outlet of the booster pump, the first pure water outlet is selectively communicated with the water inlet end of the bypass pipe or the second water inlet, and the second pure water outlet and the water outlet end of the bypass pipe are both communicated with the water outlet pipe; the second concentrated water port is connected with a wastewater pipe, and the first concentrated water port is selectively communicated with the second water inlet or the wastewater pipe. According to the water purification system and the control method disclosed by the invention, water production modes of the water purification system can be increased, the filtering effect is improved, and the use experience of a user is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of water purification, and particularly to a water purification system and a control method thereof. Background Art

[0002] With the improvement of people's living standards, water purification devices such as water purifiers or pipeline machines that can filter and purify drinking water have been more and more widely used, greatly meeting people's needs for water use safety.

[0003] The water purification devices provided by the prior art usually include a booster pump and an RO membrane filter element connected in sequence by pipelines. Among them, the RO membrane filter element is the core filtering device of the water purification device. This kind of water purification device usually has a water production mode and a flushing mode. In the water production mode, tap water passes through the pre-filtration of the pre-filtering device and the boosting of the booster pump in sequence and then enters the RO membrane filter element, and the produced pure water is supplied to the drinking water end through the water supply pipe; in the flushing mode, tap water flushes the filter element to avoid blockage of the RO membrane filter element.

[0004] The water quality in different places is uneven. The existing household water purification device modes are relatively fixed and single, and it is difficult to adapt to the water purification needs of different water qualities in various places, thus affecting the use experience of the water purification device. Summary of the Invention

[0005] The first technical problem to be solved by the present invention is to provide a water purification system, which can effectively solve the problem that it is difficult to meet the user's water use adjustment needs due to the single mode of the existing water purification system, enhance the mode of the water purification system, improve the use flexibility of the water purification system, and meet the diverse water use needs of users.

[0006] The second technical problem to be solved by the present invention is to provide a control method for a water purification system, which can effectively solve the problem that the water production mode of the existing water purification system is difficult to be adjusted according to water quality and user needs, enhance the filtering effect of the water purification system, and improve the use experience of the water purification system.

[0007] The above technical problems are solved by the following technical solutions:

[0008] A water purification system includes a booster pump, a first filtering device, a second filtering device and a bypass pipe. The bypass pipe is arranged in parallel with the second filtering device. The first filtering device has a first water inlet, a first pure water outlet and a first concentrated water outlet. The second filtering device has a second water inlet, a second pure water outlet and a second concentrated water outlet. The first water inlet is communicated with the outlet of the booster pump. The first pure water outlet is selectively communicated with the water inlet end of the bypass pipe or the second water inlet. The second pure water outlet and the water outlet end of the bypass pipe are both communicated with the water outlet pipe;

[0009] The second concentrated water outlet is connected to a wastewater pipe, and the first concentrated water outlet is selectively communicated with the second water inlet or the wastewater pipe;

[0010] The water inlet of the booster pump is connected to a water inlet pipe, and a water inlet TDS detection device is arranged on the water inlet pipe. The water purification system further includes a controller, and the water inlet TDS detection device is communicatively connected to the controller; a water outlet TDS detection device is arranged on the water outlet pipe, and the water outlet TDS detection device is communicatively connected to the controller.

[0011] Compared with the background art, the water purification system of the present invention has the following beneficial effects: The water purification system provided by the present invention can detect the water quality through the TDS detection device. When the water quality is relatively good, in the normal water production mode of the water purification system, part of the raw water is filtered by the first filtering device to generate pure water, and the concentrated water formed by the filtration of the first filtering device can be supplied to the second filtering device for secondary filtration to form another part of pure water. Compared with the conventional water purification system with only one filtering device, since it can realize the secondary filtration of the concentrated water, it can increase the amount of pure water generated after filtration, reduce the amount of wastewater, reduce water resource waste, and improve the filtration effect while meeting the water quality requirements after filtration; when the water quality is relatively poor, the water purification system is in the strong purification water production mode. Since the pure water flowing out of the first filtering device can be filtered again by the second filtering device, the purity of the water flowing out of the second filtering device can be effectively improved, thereby enhancing the filtration efficiency and filtration effect of the entire water purification system and meeting the user's demand for high-purity drinking water. That is, the water purification system provided in this embodiment can select the water production mode of the water purification system according to the filtration requirements of different water qualities or the user's requirements for the purity of the water outlet, reduce water resource waste and energy consumption while meeting the filtration effect, and improve the user's use experience.

[0012] In one embodiment, the water purification system further includes an electromagnetic three-way valve, which has a first filtration inlet, a second filtration inlet and a filtration outlet. The first filtration inlet is communicated with the first pure water outlet through a pure water pipe, the second filtration inlet is communicated with the first concentrated water outlet, the filtration outlet is communicated with the second water inlet, and the water inlet end of the bypass pipe is connected to the pure water pipe.

[0013] In one embodiment, a bypass control valve is arranged on the bypass pipe, and the bypass control valve is used to control the on-off of the bypass pipe.

[0014] In one embodiment, the water purification system further includes a wastewater three-way valve, which has a first wastewater inlet, a second wastewater inlet and a wastewater outlet. The second wastewater inlet is communicated with the second concentrated water outlet, the wastewater outlet is communicated with the wastewater pipe, and the first wastewater inlet is communicated with the first concentrated water outlet.

[0015] In one embodiment, a drainage control device is provided on the wastewater pipe. The drainage control device includes a first drainage valve and a second drainage valve connected in series on the wastewater pipe. The first drainage valve is located upstream of the second drainage valve, and both the first drainage valve and the second drainage valve are solenoid valves.

[0016] When the first drainage valve is closed, it has a first maximum allowable flow rate. When the second drainage valve is closed, it has a second maximum allowable flow rate, and the second maximum allowable flow rate is greater than zero and less than the first maximum allowable flow rate.

[0017] When the first drainage valve is open and the second drainage valve is closed, the drainage control device is in the first drainage state; when the first drainage valve is closed and the second drainage valve is open, the drainage control device is in the second drainage state; when both the first drainage valve and the second drainage valve are open, the drainage control device is in the fully open drainage state.

[0018] The above second technical problem is solved by the following technical solution:

[0019] A control method for a water purification system, used to control the water purification system as described above. The control method includes:

[0020] During the water production process, according to the inlet TDS value of the first filtration device and / or according to the outlet TDS value of the outlet pipe, control the water purification system to switch between different working modes. The working modes include a conventional water production mode and a strong purification water production mode.

[0021] Control to connect the first pure water outlet to the inlet end of the bypass pipe and connect the first concentrated water outlet to the second inlet when the water purification system is in the conventional water production mode.

[0022] Control to connect the first pure water outlet to the second inlet and connect the first concentrated water outlet to the wastewater pipe when the water purification system is in the strong purification water production mode.

[0023] Compared with the background technology, the beneficial effects of the control method of the water purification system of the present invention are as follows: By selecting the conventional water production mode or the strong purification water production mode according to the inlet TDS value and / or the outlet TDS value, the water production mode of the water purification system can be selected according to the filtration requirements of different water qualities or the user's requirements for the purity of the outlet water, while meeting the filtration effect, reducing water resource waste and energy consumption, and improving the user experience.

[0024] In one embodiment, when the inlet TDS value is greater than the first inlet TDS threshold and less than or equal to the second inlet TDS threshold, the water purification system is controlled to be in the normal water production mode; when the inlet TDS value is greater than the second inlet TDS threshold, the water purification system is controlled to be in the strong purification water production mode;

[0025] Or, when the outlet TDS value is greater than the first outlet TDS threshold and less than or equal to the second outlet TDS threshold, the water purification system is controlled to be in the normal water production mode; when the outlet TDS value is greater than the second outlet TDS threshold, the water purification system is controlled to be in the strong purification water production mode;

[0026] Or, when the inlet TDS value is between the first inlet TDS threshold and the second inlet TDS threshold and the outlet TDS value is less than or equal to the second outlet TDS value, the water production mode is controlled to be in the normal water production mode; when the inlet TDS value is greater than the second inlet TDS threshold or the outlet TDS value is greater than the second outlet TDS threshold, the water purification system is controlled to be in the strong purification water production mode.

[0027] In one embodiment, a drainage control device is provided on the wastewater pipe. The drainage control device includes a first drainage valve and a second drainage valve connected in series on the wastewater pipe. The first drainage valve is located upstream of the second drainage valve, and both the first drainage valve and the second drainage valve are solenoid valves;

[0028] When the first drainage valve is closed, it has a first maximum allowable flow rate, and when the second drainage valve is closed, it has a second maximum allowable flow rate. The second maximum allowable flow rate is greater than zero and less than the first maximum allowable flow rate;

[0029] The working mode further includes a water-saving water production mode;

[0030] When the inlet TDS value is less than the first inlet TDS threshold or the outlet TDS value is less than the first outlet TDS threshold, the water purification system is in the water-saving water production mode, connecting the first pure water outlet to the inlet end of the bypass pipe, connecting the first concentrated water outlet to the second water inlet, and controlling the first drainage valve and the second drainage valve to be closed;

[0031] When the water purification system is in the normal water production mode or the strong purification water production mode, the first drainage valve is controlled to be closed and the second drainage valve is controlled to be opened.

[0032] In one embodiment, the working mode further includes a flushing mode; when the water purification system is in the flushing mode, the first pure water outlet is disconnected from the water inlet end of the bypass pipe and the second water inlet, the first concentrated water outlet is communicated with the second water inlet, and the first drain valve and the second drain valve are controlled to open;

[0033] Wherein, after the water purification system finishes water production in the strong purification water production mode, the water purification system is controlled to enter the flushing mode.

[0034] In one embodiment, when the water purification system is started and operated for the first time, or when the time interval between two adjacent starts of the water purification system is greater than or equal to a preset interval duration, the water purification system is controlled to be locked to operate in the conventional water production mode until the cumulative duration of filtration of the water purification system in the conventional water production mode is greater than a preset cumulative duration, and then the inlet TDS value or the outlet TDS value is obtained. Description of the Drawings

[0035] Figure 1 It is a schematic structural diagram of the water purification system provided in Embodiment 1 of the present invention;

[0036] Figure 2 It is a schematic diagram of the control method provided in Embodiment 2 of the present invention;

[0037] Figure 3 It is a flowchart of the control method provided in Embodiment 3 of the present invention.

[0038] Label Description:

[0039] 1. Prefiltration device; 2. Booster pump; 3. First filtration device; 31. First water inlet; 32. First pure water outlet; 33. First concentrated water outlet; 4. Second filtration device; 41. Second water inlet; 42. Second pure water outlet; 43. Second concentrated water outlet; 5. Outlet pipe; 6. Bypass pipe; 7. Bypass control valve; 8. Waste water pipe; 9. Drainage control device; 91. First drain valve; 92. Second drain valve; 10. Concentrated water discharge pipe; 20. Electromagnetic three-way valve; 201. First filtration inlet; 202. Second filtration inlet; 203. Filtration outlet; 30. Waste water three-way valve; 301. First waste water inlet; 302. Second waste water inlet; 303. Waste water outlet; 40. Inlet TDS detection device; 50. Outlet TDS detection device; 60. Inlet switch valve; 70. Check valve; 80. Pressure switch; 90. Outlet switch; 110. Inlet pipe; 120. Inlet communication pipe. Detailed Embodiments

[0040] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the protection scope of the present application.

[0041] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0042] The terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, unless otherwise stated, the meaning of "a plurality" is two or more.

[0043] In the description of the present application, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0044] Embodiment 1

[0045] This embodiment provides a water purification system, which can be applied to water purification systems such as water purifiers and pipeline machines to enrich the functions of the water purification system and improve the user experience of the water purification system while meeting the demand for pure drinking water.

[0046] As Figure 1As shown, specifically, the water purification system includes a booster pump 2, a first filtration device 3, a second filtration device 4, a water outlet pipe 5, and a bypass pipe 6. Among them, the first filtration device 3 has a first water inlet 31, a first pure water outlet 32, and a first concentrated water outlet 33, and the second filtration device 4 has a second water inlet 41, a second pure water outlet 42, and a second concentrated water outlet 43; the first water inlet 31 is communicated with the outlet of the booster pump 2, the bypass pipe 6 is arranged in parallel with the second filtration device 4, and the first pure water outlet 32 can be selectively communicated with the water inlet end of the bypass pipe 6 or the second water inlet 41; the second pure water outlet 42 and the water outlet end of the bypass pipe 6 are both communicated with the water outlet pipe 5; the second concentrated water outlet 43 is connected to a waste water pipe 8, and the first concentrated water outlet 33 is selectively communicated with the second water inlet 41 or the waste water pipe 8.

[0047] The water purification system provided in this embodiment has a conventional water production mode and a strong purification water production mode.

[0048] When the water purification system is in the conventional water production mode, the first pure water outlet 32 is communicated with the water inlet end of the bypass pipe 6, and the first concentrated water outlet 33 is communicated with the second water inlet 41. Water flows from the inlet end of the booster pump 2 into the booster pump 2, is pressurized by the booster pump 2, and then enters the first filter element inside the first filtration device 3 from the first water inlet 31. The first filter element filters the water, and the pure water generated by the filtration flows out of the first pure water outlet 32 and flows through the bypass pipe 6 to the water outlet pipe 5; at the same time, the concentrated water generated by the filtration of the first filter element is discharged from the first concentrated water outlet 33 of the first filtration device 3 and enters the second filtration device 4 through the second water inlet 41. The second filter element of the second filtration device 4 performs secondary filtration on the incoming concentrated water. The pure water generated by the secondary filtration flows through the second pure water outlet 42 to the water outlet pipe 5, and the concentrated water generated by the secondary filtration is discharged to the waste water pipe 8 through the second concentrated water outlet 43; the pure water flowing out of the second pure water outlet 42 and the bypass pipe 6 is supplied to the drinking water end through the water outlet pipe 5.

[0049] When the water purification system is in the strong purification water production mode, the first pure water outlet 32 is disconnected from the bypass pipe 6, the first pure water outlet 32 is communicated with the second water inlet 41, and the first concentrated water outlet 33 is communicated with the waste water pipe 8. After the external incoming water is pressurized by the booster pump 2, it enters the first filtration device 3 through the first water inlet 31 for primary filtration. The pure water generated by the first filtration device 3 enters the second filtration device 4 through the second water inlet 41 and is filtered again to form pure water with a higher purity. The pure water is supplied to the drinking water end from the water outlet pipe 5; at the same time, the concentrated water generated by the filtration of the first filtration device 3 flows through the first concentrated water outlet 33 to the waste water pipe 8, and the concentrated water generated by the second filtration device 4 flows through the second concentrated water outlet 43 to the waste water pipe 8 to realize the discharge of waste water.

[0050] The water purification system provided in this embodiment has at least a conventional water production mode and a strong purification water production mode. In the conventional water production mode, raw water is filtered by the first filtering device 3 to produce a part of pure water, and the concentrated water formed by the filtration of the first filtering device 3 can be supplied to the second filtering device 4 for secondary filtration to form part of pure water. Compared with the conventional water purification system with only one filtering device, since it can realize the secondary filtration of the concentrated water, it can increase the amount of pure water produced after filtration, reduce the amount of wastewater, reduce water resource waste, and improve the filtering effect while meeting the water quality requirements after filtration; when the water purification system is in the strong purification water production mode, since the pure water flowing out of the first filtering device 3 can be filtered again by the second filtering device 4, the purity of the water flowing out of the second filtering device 4 can be effectively improved, thereby enhancing the filtering efficiency and filtering effect of the entire water purification system, meeting the user's demand for high-purity drinking water, or meeting the filtering demand for raw water with poor water quality. That is, the water purification system provided in this embodiment can select the water production mode of the water purification system according to the filtering requirements of different water qualities or the user's requirements for the purity of the outlet water, reduce water resource waste and energy consumption while meeting the filtering effect, and improve the user's use experience.

[0051] In one embodiment, both the first filtering device 3 and the second filtering device 4 are RO membrane filtering devices, and the filtering effect is better. In other embodiments, it is also possible that the first filtering device 3 is an RO membrane filtering device and the second filtering device 4 is a desalination filtering device to reduce the salt content in the final pure water and improve the water use experience in the strong purification water production mode.

[0052] To better achieve the water inlet control of the second water inlet 41, the water purification system further includes a water inlet control device, and the water inlet control device can control the selective communication between the first pure water outlet 32 or the first concentrated water outlet 33 and the second water inlet 41. In one embodiment, the water inlet control device includes an electromagnetic three-way valve 20, and the electromagnetic three-way valve 20 has a first filtering inlet 201, a second filtering inlet 202 and a filtering outlet 203. The first filtering inlet 201 is communicated with the first pure water outlet 32, the second filtering inlet 202 is communicated with the second pure water outlet 42, and the filtering outlet 203 is communicated with the second water inlet 41. A control valve core is arranged in the electromagnetic three-way valve 20, and the control valve core can control the filtering outlet 203 to selectively communicate with the first filtering inlet 201 or the second filtering inlet 202. The electromagnetic three-way valve 20 is an electromagnetic valve, and the electromagnetic three-way valve 20 is communicatively connected to the controller so that the controller can automatically control the switching of the conduction mode of the electromagnetic three-way valve 20.

[0053] In other embodiments, the water inlet control device may include two water inlet control valves, one of the water inlet control valves is arranged on the connecting pipeline between the first pure water outlet 32 and the second water inlet 41, and the other water inlet control valve may be arranged on the connecting pipeline between the first concentrated water outlet 33 and the second water inlet 41.

[0054] In one embodiment, a bypass control valve 7 is provided on the bypass pipe 6, whereby the on / off of the bypass pipe 6 can be controlled, thereby controlling the flow direction of the water flowing out of the first pure water outlet 32. Specifically, the first filtration inlet 201 and the first pure water outlet 32 are connected by a pure water pipe, and the water inlet end of the bypass pipe 6 is connected to the water outlet pipe 5. In other embodiments, a water outlet three-way valve may be provided. The water inlet port of the water outlet three-way valve is communicated with the first pure water outlet 32, one water outlet port is connected to the water inlet end of the bypass pipe 6, and the other water outlet port is connected to the second water inlet 41. That is, the water outlet three-way valve controls the flow direction of the water flowing out of the first pure water outlet 32.

[0055] To improve the automatic control of wastewater discharge, in one embodiment, the water purification system further includes a wastewater three-way valve 30. The wastewater three-way valve 30 has a first wastewater inlet 301, a second wastewater inlet 302, and a wastewater outlet 303. The first wastewater inlet 301 is communicated with the first concentrated water outlet 33 through a concentrated water discharge pipe 10, and the second wastewater inlet 302 and the wastewater outlet 303 are connected in series to the wastewater pipe 8.

[0056] The wastewater three-way valve 30 has a first conduction state in which the second wastewater inlet 302 and the wastewater outlet 303 are conducted, and a second conduction state in which both the second wastewater inlet 302 and the first wastewater inlet 301 are conducted to the wastewater outlet 303. When the water purification system is in the conventional water production mode, the wastewater three-way valve 30 is in the second conduction state to increase the resistance of the water flow from the first concentrated water outlet 33 to the wastewater pipe 8, so that the concentrated water discharged from the first concentrated water outlet 33 can enter the second filtration device 4.

[0057] Furthermore, the second filtration inlet 202 and the concentrated water discharge pipe 10 are communicated through an inlet communication pipe 120, simplifying the pipeline layout of the water purification system. That is, the concentrated water flowing out of the first concentrated water outlet 33 can sequentially flow through the concentrated water discharge pipe 10, the inlet communication pipe 120, the second filtration inlet 202, and the filtration outlet 203 to the second water inlet 41.

[0058] To further enrich the functions of the water purification system, in one embodiment, a drainage control device 9 is provided on the wastewater pipe 8. The drainage control device 9 is used to control the switching of the wastewater pipe 8 among a first drainage state, a second drainage state, and a fully open drainage state, and the maximum allowable flow rates of the first drainage state, the second drainage state, and the fully open drainage state gradually increase. The drainage control device 9 is provided downstream of the wastewater three-way valve 30.

[0059] The above settings enable the water purification system to also have a water-saving water production mode: when the water purification system is in the normal water production mode or the strong purification water production mode, the drainage control device 9 is in the second drainage state; when the water purification system is in the water-saving water production mode, the drainage control device 9 is in the first drainage state, and the first pure water outlet 32 is communicated with the bypass pipe 6, and the first concentrated water outlet 33 is communicated with the second water inlet 41.

[0060] That is, when the water purification system is in the water-saving water production mode, the water flow is pressurized by the booster pump 2 and then enters the first filtering device 3. The pure water generated by filtering through the first filtering device 3 flows through the first pure water outlet 32 and the bypass pipe 6 to the water outlet pipe 5; the concentrated water generated by filtering through the first filtering device 3 flows to the second filtering device 4 for re-filtering, and the concentrated water generated by filtering through the second filtering device 4 is discharged to the waste water pipe 8. Since the maximum allowable flow rate of the waste water pipe 8 in the water-saving water production mode is less than the maximum allowable flow rate in the normal water production mode, the waste water drainage flow rate generated by the second filtering device 4 is reduced compared with the normal water production mode, resulting in an increase in the pressure on the raw water side in the second filtering device 4, so that the pure water generated by filtering through the second filtering device 4 increases; due to the increase in the pressure on the raw water side in the second filtering device 4, it will further cause an increase in the waste water discharge pressure of the first filtering device 3, so that the water pressure on the raw water side of the first filtering device 3 will also increase, further increasing the amount of pure water generated by filtering through the first filtering device 3. Thus, it can effectively reduce the waste water discharge volume, increase the pure water flow rate of the water outlet pipe 5, and achieve water saving.

[0061] The above settings of the drainage control device 9 enable the water purification system to also have two flushing modes, which are the first flushing mode and the second flushing mode respectively:

[0062] When the water purification system is in the first flushing mode, the first concentrated water outlet 33 is communicated with the second water inlet 41, and the drainage control device 9 is in the fully open drainage state. The water flow enters the first filtering device 3 after passing through the booster pump 2. Since the waste water pipe 8 is in the fully open drainage state, the drainage pressure of the second concentrated water outlet 43 is relatively small, while the pressure of the water flow from the first water inlet 31 to the first pure water outlet 32 and the pressure of the water flow from the second water inlet 41 to the second pure water outlet are relatively large. Thus, the water flow entering from the first water inlet 31 flushes the first filter element and then directly discharges from the first concentrated water outlet 33 to the inside of the second filtering device 4, and after flushing the second filter element of the second filtering device 4, it discharges from the second concentrated water outlet 43 to the waste water pipe 8. Thereby, the high-concentration ions accumulated on the raw water side of the first filtering device 3 and the raw water side of the second filtering device 4 are discharged to the waste water pipe 8 through the water flow, realizing the flushing of the first filtering device 3 and the second filtering device 4, avoiding the blockage of the first filter element and the second filter element, and ensuring the filtering effect of the first filter element and the second filter element.

[0063] When the water purification system is in the second flushing mode, both the first concentrated water outlet 33 and the second concentrated water outlet 43 are connected to the waste water pipe 8. The incoming water flow is pressurized by the booster pump 2 and enters the first filtering device 3 from the first water inlet 31. After flushing the first filter element, it is directly discharged from the first concentrated water outlet 33 into the waste water pipe 8, realizing the flushing of the first filtering device 3. At this time, since the first concentrated water outlet 33 is directly connected to the waste water pipe 8, the resistance of the water flow directly discharging from the first concentrated water outlet 33 to the waste water pipe 8 is much smaller than the resistance of the water flow passing through the second filtering device 4 and then discharging to the waste water pipe 8. Therefore, almost all of the water flow flowing out from the first concentrated water outlet 33 is directly discharged into the waste water pipe 8 and no longer passes through the second filtering device 4.

[0064] In one embodiment, the drainage control device 9 includes a first drainage valve 91 and a second drainage valve 92 arranged in series. The first drainage valve 91 is located upstream of the second drainage valve 92, and both the first drainage valve 91 and the second drainage valve 92 are normally closed solenoid valves. When the first drainage valve 91 is closed, it has a first maximum allowable flow rate. When the second drainage valve 92 is closed, it has a second maximum allowable flow rate, and the second maximum allowable flow rate is greater than zero and less than the first maximum allowable flow rate. When the first drainage valve 91 is open and the second drainage valve 92 is closed, the drainage control device 9 is in the first drainage state. When the first drainage valve 91 is closed and the second drainage valve 92 is open, the drainage control device 9 is in the second drainage state. When both the first drainage valve 91 and the second drainage valve 92 are open, the drainage control device 9 is in the fully open drainage state. Thus, by controlling the opening and closing of the first drainage valve 91 and the second drainage valve 92, the drainage flow rate of the waste water pipe 8 can be controlled, so as to better control the switching of the water purification system between the water-saving water production mode and other water production modes.

[0065] Specifically, the first drainage valve 91 has a first drainage port. When the first drainage valve 91 is closed, the first drainage port has a first maximum allowable flow rate. When the first drainage valve 91 is open, the first drainage valve 91 has a first valve opening flow rate. The second drainage valve 92 has a second drainage port. When the first drainage valve 91 is closed, the second drainage port has a second maximum allowable flow rate. When the second drainage valve 92 is open, the second drainage valve 92 has a second valve opening flow rate. The first drainage port is larger than the second drainage port, that is, the first maximum allowable flow rate is greater than the second maximum allowable flow rate.

[0066] Both the first drainage valve 91 and the second drainage valve 92 can adopt existing mature structures, and the specific structures thereof are not limited in this embodiment. In other embodiments, the drainage control device 9 can also adopt a flow regulating valve, and the flow regulating valve can regulate the flow rate of the waste water pipe 8 to realize the switching of the water purification system between the water-saving water production mode and other water production modes.

[0067] In an embodiment, to reduce the probability of clogging of the first filtering device 3, the water purification system further includes a pre-filtering device 1. The water inlet of the pre-filtering device 1 is used to introduce the raw water flow. The water outlet of the pre-filtering device 1 is connected to the water inlet of the booster pump 2. That is, the booster pump 2 is arranged between the pre-filtering device 1 and the first filtering device 3 to achieve rough filtration of the raw water, reduce large particle impurities in the water flowing to the booster pump 2, and reduce the probability of clogging of the booster pump 2 and the first filtering device 3. The pre-filtering device 1 can be, but is not limited to, a PPC composite filter element.

[0068] The pre-filtering device 1 and the booster pump 2 are connected through a water inlet pipe 110. An inlet water switch valve 60 is arranged on the water inlet pipe 110. The inlet water switch valve 60 is used to control the on-off of the water flow to the booster pump 2 to achieve the opening and closing control of the entire water purification system. The inlet water switch valve 60 is preferably an electromagnetic valve. The water purification system has a controller, and the controller is communicatively connected to the inlet water switch valve 60 to better meet the electric control of the water purification system.

[0069] In an embodiment, an inlet water TDS detection device 40 is arranged on the water inlet pipe 110. The inlet water TDS detection device 40 is arranged between the inlet water switch valve 60 and the booster pump 2 to detect the inlet water TDS value of the water inlet pipe 110. The inlet water TDS detection device 40 is communicatively connected to the controller so that the detected value of the inlet water TDS detection device 40 can be sent to the controller. The setting of the inlet water TDS detection device 40 enables users to select the water production mode of the water purification system according to the inlet water TDS value, improving the rationality of the user's selection of the water production mode; or, the controller can automatically select the water production mode according to the inlet water TDS value detected by the inlet water TDS detection device 40 to achieve the automation degree of the water production mode selection and improve the user experience.

[0070] In an embodiment, a first inlet water TDS threshold value and a second inlet water TDS threshold value corresponding to the inlet water TDS detection device 40 are preset in the controller. The first inlet water TDS threshold value is less than the second inlet water TDS threshold value. When the inlet water TDS value detected by the inlet water TDS detection device 40 is less than or equal to the first inlet water TDS threshold value, the controller controls the water purification system to be in the water-saving water production mode; when the inlet water TDS value detected by the inlet water TDS detection device 40 is greater than the first inlet water TDS threshold value and less than or equal to the second inlet water TDS threshold value, the controller controls the water purification system to be in the conventional water production mode; when the inlet water TDS value detected by the inlet water DS detection device is greater than the second inlet water TDS threshold value, the controller controls the water purification system to be in the strong purification water production mode.

[0071] That is, when the influent TDS value entering the first filtration device 3 is less than or equal to the first influent TDS threshold, it indicates that the accumulation of ions generated by filtration on the raw water side decreases. The pressure difference between the raw water side and the purified water side of the first filtration device 3 and the second filtration device 4 can be further increased to reduce the concentrated water discharge, increase the production of pure water, and reduce the waste of water resources. When the influent TDS value detected by the influent TDS detection device 40 is between the first influent TDS threshold and the second influent TDS threshold, it indicates that the water quality entering the first filtration device 3 is average. If the concentrated water discharge is reduced, it is easy to cause the first filter element of the first filtration device 3 to be blocked. Therefore, controlling the water purification system to be in the conventional water production mode can balance the filtration effect and the service life of the first filtration device 3. When the influent TDS value detected by the influent TDS detection device 40 is greater than the second influent TDS threshold, it indicates that the water quality entering the first water inlet 31 is poor. Only using the first filtration device 3 for a single filtration can meet the requirement of the effluent purity. Therefore, the pure water generated by the first filtration device 3 is filtered again by the second filtration device 4, which can better meet the effluent purity requirement of the water outlet pipe 5.

[0072] To detect the TDS value of the pure water in the water outlet pipe 5, an effluent TDS detection device 50 is provided in the water outlet pipe 5. The effluent TDS detection device 50 is communicatively connected to the controller. The effluent TDS detection device 50 can detect the effluent TDS value in the water outlet pipe 5, so that the controller can better determine the filtration effect of the water purification system and whether the effluent TDS value of the water purification system meets the requirements. The outlet end of the bypass pipe 6 is located between the effluent TDS detection device 50 and the second pure water outlet 42.

[0073] In an embodiment, when the effluent TDS value detected by the effluent TDS detection device 50 is less than or equal to the second effluent TDS threshold, it is determined that the pure water in the water outlet pipe 5 meets the drinking water requirement. When the effluent TDS value detected by the effluent TDS detection device 50 is greater than the second preset effluent TDS value, it is determined that the pure water in the water outlet pipe 5 does not meet the drinking water requirement. At this time, if the water purification system is in the conventional water production mode, the controller can control the water purification system to switch to the strong purification water production mode to enhance the filtration effect. If the water production mode is already in the strong purification water production mode at this time, the controller can control the alarm module to issue an alarm to remind the user to repair the water purification system, or allow the controller to switch the water purification system to the flushing mode to flush the first filtration device 3 or the first filtration device 3 and the second filtration device 4.

[0074] A check valve 70 is also provided on the water outlet pipe 5. The check valve 70 only allows water to flow from the water inlet end of the water outlet pipe 5 to the water outlet end. The check valve 70 is used to prevent water from flowing back into the second filtration device 4 when there are fluctuations in the water pressure at the water usage end or the drinking water end is blocked, which may cause excessive internal pressure in the second filtration device 4 and damage it, or water from flowing back into the first filtration device 3 through the bypass pipe 6 of the water flow channel, resulting in excessive internal pressure in the first filtration device 3, thus ensuring the safe use of the second filtration device 4 and the first filtration device 3.

[0075] A water outlet switch 90 is provided at the water outlet end of the water outlet pipe 5. The water outlet switch 90 can be a faucet or other switch structure that can be manually controlled or electronically controlled to discharge water. This embodiment does not limit this. The water outlet end of the water outlet switch 90 forms the drinking water end.

[0076] Furthermore, a pressure switch 80 is also provided on the water outlet pipe 5. The pressure switch 80 is located downstream of the check valve 70 and is communicatively connected to the controller. The pressure switch 80 is used to detect the pressure of the water outlet pipe 5 to determine whether the drinking water end is opened. That is, when the drinking water end is opened, the pressure of the water outlet pipe 5 decreases. When the pressure value detected by the pressure switch 80 is lower than the preset starting pressure value, it is determined that there is water usage at the drinking water end, and the controller can control the filtration device to start to prepare drinking water; when the user closes the drinking water end, the water pressure in the water outlet pipe 5 increases. When the pressure switch 80 detects that the water pressure in the water outlet pipe 5 is greater than the preset closing pressure, the controller controls the filtration device to close.

[0077] Embodiment 2

[0078] This embodiment provides a control method for a water purification system, which is applied to the water purification system in Embodiment 1 to control the automatic operation of the water purification system, so as to improve the user experience of the water purification system while meeting the filtration effect of the water purification system.

[0079] As Figure 2 shown, the control method provided in this embodiment includes the following steps:

[0080] During the water production process, according to the inlet TDS value of the first filtration device 3 and / or according to the outlet TDS value of the water outlet pipe 5, control the water purification system to switch between the normal water production mode and the strong purification water production mode;

[0081] Control to connect the first pure water outlet 32 to the water inlet end of the bypass pipe 6 and connect the first concentrated water outlet 33 to the second water inlet 41 when the water purification system is in the normal water production mode;

[0082] Control to connect the first pure water outlet 32 to the second water inlet 41 and connect the first concentrated water outlet 33 to the waste water pipe 8 when the water purification system is in the strong purification water production mode.

[0083] The control method of the water purification system provided by this embodiment can, during the water production process, automatically select and adjust the water production mode by the controller according to the inlet TDS value or the outlet TDS value, meet the purity requirements of the produced pure water, take into account the requirements of water conservation and energy conservation, improve the filtering effect and user experience of the water purification system, and better meet the filtering requirements for different water qualities.

[0084] In one embodiment, when the inlet TDS value is greater than the first inlet TDS threshold and less than or equal to the second inlet TDS threshold, the water purification system is controlled to be in the normal water production mode; when the inlet TDS value is greater than the second inlet TDS threshold, the water purification system is controlled to be in the strong purification water production mode. That is, the timing of switching the water production mode is judged by the inlet TDS value, and thus the required water production mode can be better determined according to the inlet water quality.

[0085] In another embodiment, when the outlet TDS value is greater than the first outlet TDS threshold and less than or equal to the second outlet TDS threshold, the water purification system is controlled to be in the normal water production mode; when the outlet TDS value is greater than the second outlet TDS threshold, the water purification system is controlled to be in the strong purification water production mode. That is, the water production mode of the water purification system is selected by the outlet TDS value, and thus it can be better ensured that the outlet TDS value of the water flowing out of the outlet pipe 5 meets the requirements of drinking water.

[0086] In still another embodiment, the inlet TDS value and the outlet TDS value can be taken into account simultaneously to better ensure that the water production mode is not only adapted to the water quality but also can better meet the purity requirements of the outlet water. Specifically, when the inlet TDS value is greater than the first inlet TDS threshold and less than or equal to the second inlet TDS threshold, and the outlet TDS value is less than or equal to the second outlet TDS threshold, the water purification system is controlled to be in the normal water production mode; when the inlet TDS value is greater than the second inlet TDS threshold, or when the outlet TDS value is greater than the second outlet TDS threshold, the water purification system is controlled to be in the strong purification water production mode.

[0087] In one embodiment, the first inlet TDS threshold is 140 - 160 ppm, the second inlet TDS threshold is 450 - 550 ppm; the first outlet TDS threshold is 20 - 30 ppm, and the second outlet TDS threshold is 40 - 60 ppm.

[0088] To further achieve energy conservation of the water purification system and the water purification system, in one embodiment, the provided control method further includes:

[0089] When the inlet TDS value is greater than the first inlet TDS threshold, the drainage control device 9 is controlled to be in the second drainage state;

[0090] When the inlet TDS value is less than or equal to the first inlet TDS threshold, or the outlet TDS value is less than or equal to the first outlet TDS threshold, the water purification system is controlled to be in the water-saving water production mode, so that the first pure water outlet 32 is communicated with the water inlet end of the bypass pipe 6, the first concentrated water outlet 33 is communicated with the second water inlet 41, and the drainage control device 9 is in the first drainage state.

[0091] That is, when the water purification system is in the conventional water production mode and the strong purification water production mode, the drainage control device 9 discharges the generated concentrated water at the normal waste water drainage flow rate; when the water purification system is in the energy-saving mode, the waste water discharge amount is reduced and the pure water output amount is increased, so as to achieve water saving.

[0092] Further, the control method further includes: when the water purification system is in the strong purification water production mode and the outlet TDS value is greater than the second outlet TDS threshold, the controller controls the alarm module to issue an alarm. When the outlet TDS value is higher than the second outlet TDS threshold in the strong purification water production mode, it indicates that the overall filtration performance of the water purification system is poor, and the TDS value of the prepared pure water is still relatively high, making it difficult to meet the drinking requirements. By controlling the alarm module to issue an alarm, it can prompt the user to repair and check the water purification system even.

[0093] Embodiment III

[0094] This embodiment provides a control method for a water purification system, and the control method provided in this embodiment is a further improvement based on the control method provided in Embodiment II.

[0095] As Figure 3 shown, the control method provided in this embodiment specifically includes:

[0096] Step S101, the water purification system is powered on and standby;

[0097] Step S102, receiving a water production instruction;

[0098] In one embodiment, the controller determines whether there is a water production instruction according to the pressure value detected by the pressure switch 80. When the drinking water end is opened, the water pressure detected by the pressure switch 80 decreases. When the pressure switch 80 detects that the water pressure in the water outlet pipe 5 is less than or equal to the preset starting water pressure, the controller determines that there is a water production instruction.

[0099] In another embodiment, a water production start button can be set on the water purification system. The water production start button is communicatively connected to the controller. When the water production start button is pressed, the controller determines that it has received a water production instruction.

[0100] In another embodiment, a touch screen may be provided on the water purification system, and the user inputs a water production instruction to the controller through the touch screen; alternatively, a voice recognition device may be provided on the water purification system. The voice recognition device is communicatively connected to the controller. The voice recognition device picks up the user's voice information and sends it to the controller, and the controller analyzes the voice information to determine whether there is a water production instruction.

[0101] Step S103: Determine whether the preset water production mode operation conditions are met. If so, execute step S104; if not, execute step S108.

[0102] When the water purification system is powered on for the first time, or when the water purification system has not been used for a long time, the TDS value of the water produced in the initial stage of water production by the water purification system is relatively high. At this time, it is difficult for the detection of the inlet TDS value or the outlet TDS to effectively reflect the water quality. Therefore, if the water production mode is selected according to the inlet TDS value or the outlet TDS value, the selected water production mode may not match the water quality of the water to be filtered. The preset water production operation conditions include: the water purification system is started and operated for the first time, or the time interval between two adjacent starts of the water purification system is greater than or equal to the preset time interval, or the cumulative operation time of the water production mode of the water purification system locked to the preset water production mode has not reached the preset cumulative time.

[0103] Step S104: Control the water production mode to be locked to the preset water production mode.

[0104] When the water quality is unknown, using the preset water production mode of the water purification system for water production can reduce the control difficulty of the water purification system and simplify the control logic.

[0105] In one embodiment, the preset water production mode is the conventional water production mode. The pure / waste water ratio in the conventional water production mode is moderate, which is more suitable as a membrane washing mode when the inlet water quality is uncertain. The strong purification water production mode has a greater load on the first filter element of the first filtering device 3, and the membrane washing effect on the first filter element in the strong purification water production mode is relatively poor compared to the conventional water production mode. Therefore, setting the preset water production mode to the conventional water production mode can meet the water production requirements while improving the membrane washing effect.

[0106] Step S105: Determine whether the water production is finished. If not, execute step S106; if so, execute step S110.

[0107] Step S106: Determine whether the cumulative water production time of the water production mode locked to the preset water production mode has reached the preset locking time. If so, execute step S107; if not, return to step S104.

[0108] In one embodiment, the preset locking duration is 8 to 20 minutes. It can be understood that since the water receiving time at the drinking water end is usually short each time, and the time required for one water production process is usually less than the preset locking time. Therefore, there is a situation where the water production mode is locked to the preset water production mode during multiple water production processes. When the cumulative water production duration during which the water production mode is continuously locked reaches the preset locking duration, the locking of the preset index mode is released.

[0109] It should be noted that the above cumulative water production duration is the total duration of multiple water productions using the preset water production mode, and the intermediate duration between two adjacent water production processes is not included in the cumulative water production duration.

[0110] Step S107: Release the locking of the preset water production mode and execute step S108;

[0111] Step S108: Select a water production mode according to the inlet TDS value or the outlet TDS value;

[0112] When the preset water production operation conditions are not met or the locking of the preset water production mode is released, the water production mode can be adjusted according to the inlet TDS value and / or the outlet TDS value, so that the water production mode matches the current water quality or the current filtration performance of the first filtration device 3 and the second filtration device 4, achieving energy conservation and water conservation while meeting the requirement of the water outlet purity.

[0113] The specific method of selecting the water production mode according to the inlet TDS value or the outlet TDS value can be set with reference to Embodiment 2, and will not be elaborated in this embodiment.

[0114] Step S109: Determine whether the water production is over. If so, execute step S110; if not, execute step S108;

[0115] Step S110: Determine whether the previous water production mode is the strong purification water production mode. If so, execute step S120; if not, execute step S130;

[0116] Since the strong purification water production mode has a relatively large load on the first filter element of the first filtration device 3, after the strong purification water production mode ends, the ion concentration accumulated on the raw water side of the first filtration device 3 is relatively large, which is likely to cause the first filter element to be blocked and affect the next use of the water purification device of the water purification system. Therefore, to ensure the filtration effect of the first filtration device 3, after each water production using the strong purification water production mode, the second flushing mode is run to flush the first filtration device 3 to reduce the probability of blockage of the first filtration device 3.

[0117] Step S120: Enter the second flushing mode. After the second flushing mode ends, execute step S130;

[0118] Specifically, after the water purification system finishes water production in the strong purification water production mode, the drainage control device 9 is controlled to switch from the second drainage state to the fully open drainage state, and water flow is introduced into the booster pump 2 to flush the first filtering device 3 with the water flow.

[0119] The operation duration of the second flushing mode is preferably 15 s to 30 s.

[0120] Step S130: Determine whether a preset flushing condition is met? If yes, execute step S140; if no, return to step S101.

[0121] Since the second flushing mode only flushes the first filtering device 3 and runs after each execution of the strong purification water production mode, and during the long-term operation of the water purification system, both the first filtering device 3 and the second filtering device 4 may be blocked. To ensure the overall filtering performance of the water purification system, when the preset flushing condition is met, both the first filtering device 3 and the second filtering device 4 need to be flushed to ensure the filtering effect of the first filtering device 3 and the second filtering device 4.

[0122] The preset flushing condition includes: the continuous operation duration of the water purification system since the last execution of the first flushing mode reaches the cumulative operation duration, or the TDS value of the water output in the strong purification water production mode is always greater than the second water output TDS threshold, or the cumulative filtration flow of the second filtering device 4 after the last execution of the first flushing mode is greater than the preset flow rate.

[0123] The preset flushing condition can be set according to the flushing requirements, and the present invention will not list them one by one.

[0124] Step S140: Enter the first flushing mode. After the first flushing mode runs to completion, return to step S101. Specifically executing the first flushing mode includes: controlling the first concentrated water outlet 33 to communicate with the second water inlet 41, and the wastewater pipe 8 is in the fully open drainage state;

[0125] Supply water flow to the booster pump 2, and make the water flow pressurized by the booster pump 2 flow through the first water inlet 31, the first concentrated water outlet 33, the second water inlet 41, the second concentrated water outlet 43 and the wastewater pipe 8 in sequence to flush the first filtering device 3 and the second filtering device 4.

[0126] Embodiment 4

[0127] This embodiment provides a control method for the water purification system, and the control method provided in this embodiment is a further improvement on the control method in Embodiment 3. The same structures as those in Embodiment 3 will not be described in detail in this embodiment.

[0128] In this embodiment, the control method further includes:

[0129] During the water production process, receive the water production mode switching instruction issued by the user;

[0130] When the target water production mode selected by the user matches the current influent TDS value or the current effluent TDS value, switch to the target water production mode.

[0131] That is, for the control method provided in this embodiment, the user can automatically select the water production mode to meet the user's own requirements for the purity of drinking water and improve the usage experience of the water purification system. And when the target water production mode selected by the user matches the current influent TDS value or the current effluent TDS value, the controller controls the water purification system to switch to the target water production mode selected by the user.

[0132] The control method further includes:

[0133] When the target water production mode selected by the user does not match the current influent TDS value and the current effluent TDS value, remind the user to select and switch to the water production mode matched by the system;

[0134] According to the user's re-selection, switch the water purification system to the water production mode selected by the user.

[0135] That is, when the target water production mode selected by the user does not match the current influent TDS value or the effluent TDS value, the system reminds the user by means of voice broadcast or screen display, etc., so as to prevent the user from randomly switching the water production mode due to lack of understanding of the filtration status, ensure the overall filtration effect of the water purification system and the water purification system, and achieve the effect of reducing energy consumption and saving water as much as possible; at the same time, this setting can enhance the interaction between the user and the water purification system and improve the user's usage experience of the water purification system.

[0136] When the user is reminded of the matched water production mode by the water purification system, the user can re-select the water production mode, and regardless of whether the water production mode selected by the user is the one recommended by the water purification system, the controller controls the water purification system to switch to the water production mode selected by the user to better meet the user's active control of the water purification system.

[0137] Furthermore, the user can select the water production mode through the mode selection button set on the water purification system, or can select the water production mode of the water purification system through the corresponding mobile phone APP.

[0138] In one embodiment, the control method further includes:

[0139] In the standby state, receive the flushing instruction issued by the user;

[0140] Execute the first flushing mode.

[0141] That is, the user can automatically select the running time of the first flushing mode.

[0142] In the specific content of the above specific embodiments, each technical feature can be combined arbitrarily without contradiction. For the sake of brevity of description, not all possible combinations of the above technical features are described. However, as long as the combinations of these technical features do not exist in contradiction, they should all be considered as the scope recorded in this specification.

[0143] The specific content of the above specific embodiments only expresses several embodiments of the present invention, and its description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent for the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be subject to the appended claims.

Claims

1. A water purification system, characterized in that, it includes a booster pump (2), a first filtration device (3), a second filtration device (4) and a bypass pipe (6). The bypass pipe (6) is arranged in parallel with the second filtration device (4). The first filtration device (3) has a first water inlet (31), a first pure water outlet (32) and a first concentrated water outlet (33). The second filtration device (4) has a second water inlet (41), a second pure water outlet (42) and a second concentrated water outlet (43). The first water inlet (31) is communicated with the outlet of the booster pump (2). The first pure water outlet (32) is selectively communicated with the inlet end of the bypass pipe (6) or the second water inlet (41). The second pure water outlet (42) and the outlet end of the bypass pipe (6) are both communicated with a water outlet pipe (5); the second concentrated water outlet (43) is connected with a waste water pipe (8), and the first concentrated water outlet (33) is selectively communicated with the second water inlet (41) or the waste water pipe (8); the inlet of the booster pump (2) is connected with a water inlet pipe (110). An inlet TDS detection device (40) is arranged on the water inlet pipe (110). The water purification system further includes a controller. The inlet TDS detection device (40) is in communication connection with the controller. An outlet TDS detection device (50) is arranged on the water outlet pipe (5). The outlet TDS detection device (50) is in communication connection with the controller.

2. The water purification system according to claim 1, characterized in that, the water purification system further includes an electromagnetic three-way valve (20). The electromagnetic three-way valve (20) has a first filtration inlet (201), a second filtration inlet (202) and a filtration outlet (203). The first filtration inlet (201) is communicated with the first pure water outlet (32) through a pure water pipe. The second filtration inlet (202) is communicated with the first concentrated water outlet (33). The filtration outlet (203) is communicated with the second water inlet (41). The inlet end of the bypass pipe (6) is connected to the pure water pipe.

3. The water purification system according to claim 2, characterized in that, a bypass control valve (7) is arranged on the bypass pipe (6). The bypass control valve (7) is used to control the on-off of the bypass pipe (6).

4. The water purification system according to claim 1, characterized in that, the water purification system further includes a waste water three-way valve (30). The waste water three-way valve (30) has a first waste water inlet (301), a second waste water inlet (302) and a waste water outlet (303). The second waste water inlet (302) is communicated with the second concentrated water outlet (43). The waste water outlet (303) is communicated with the waste water pipe (8). The first waste water inlet (301) is communicated with the first concentrated water outlet (33).

5. The water purification system according to claim 1, characterized in that, A drain control device (9) is provided on the waste water pipe (8). The drain control device (9) includes a first drain valve (91) and a second drain valve (92) connected in series on the waste water pipe (8). The first drain valve (91) is located upstream of the second drain valve (92), and both the first drain valve (91) and the second drain valve (92) are solenoid valves. When the first drain valve (91) is closed, it has a first maximum allowable flow rate. When the second drain valve (92) is closed, it has a second maximum allowable flow rate, and the second maximum allowable flow rate is greater than zero and less than the first maximum allowable flow rate.

6. A control method for a water purification system Characterized in that It is used to control the water purification system according to any one of claims 1-5. The control method includes: During the water production process, according to the inlet TDS value of the first filtration device (3) and / or according to the outlet TDS value of the outlet pipe (5), control the water purification system to switch between different working modes. The working modes include a normal water production mode and a strong purification water production mode. Control that when the water purification system is in the normal water production mode, connect the first pure water outlet (32) to the inlet end of the bypass pipe (6), and connect the first concentrated water outlet (33) to the second inlet (41). Control that when the water purification system is in the strong purification water production mode, connect the first pure water outlet (32) to the second inlet (41), and connect the first concentrated water outlet (33) to the waste water pipe (8).

7. The control method according to claim 6 Characterized in that When the inlet TDS value is greater than the first inlet TDS threshold and less than or equal to the second inlet TDS threshold, control the water purification system to be in the normal water production mode; when the inlet TDS value is greater than the second inlet TDS threshold, control the water purification system to be in the strong purification water production mode. Or, when the outlet TDS value is greater than the first outlet TDS threshold and less than or equal to the second outlet TDS threshold, control the water purification system to be in the normal water production mode. When the outlet TDS value is greater than the second outlet TDS threshold, control the water purification system to be in the strong purification water production mode. Or, when the inlet TDS value is between the first inlet TDS threshold and the second inlet TDS threshold and the outlet TDS value is less than or equal to the second outlet TDS value, control the water production mode to be in the normal water production mode; when the inlet TDS value is greater than the second inlet TDS threshold or the outlet TDS value is greater than the second outlet TDS threshold, control the water purification system to be in the strong purification water production mode.

8. The control method according to claim 7 Characterized in that A drainage control device (9) is provided on the wastewater pipe (8). The drainage control device (9) includes a first drainage valve (91) and a second drainage valve (92) connected in series on the wastewater pipe (8). The first drainage valve (91) is located upstream of the second drainage valve (92). Both the first drainage valve (91) and the second drainage valve (92) are solenoid valves. When the first drainage valve (91) is closed, it has a first maximum allowable flow rate. When the second drainage valve (92) is closed, it has a second maximum allowable flow rate. The second maximum allowable flow rate is greater than zero and less than the first maximum allowable flow rate. The working mode further includes a water-saving water production mode. When the inlet TDS value is less than the first inlet TDS threshold or the outlet TDS value is less than the first outlet TDS threshold, the water purification system is in the water-saving water production mode, connecting the first pure water outlet (32) to the inlet end of the bypass pipe (6), connecting the first concentrated water outlet (33) to the second inlet (41), and controlling the first drainage valve (91) and the second drainage valve (92) to close. When the water purification system is in the normal water production mode or the strong purification water production mode, control the first drainage valve (91) to close and control the second drainage valve (92) to open.

9. According to the control method described in claim 8, It is characterized in that The working mode further includes a flushing mode. When the water purification system is in the flushing mode, disconnect the first pure water outlet (32) from the inlet end of the bypass pipe (6) and the second inlet (41), connect the first concentrated water outlet (33) to the second inlet (41), and control the first drainage valve (91) and the second drainage valve (92) to open. Among them, after the water purification system finishes water production in the strong purification water production mode, control the water purification system to enter the flushing mode.

10. According to the control method described in any one of claims 6-9, It is characterized in that When the water purification system is started and operated for the first time, or when the time interval between two adjacent starts of the water purification system is greater than or equal to a preset interval duration, control the water purification system to be locked in the normal water production mode until the cumulative duration of filtration of the water purification system in the normal water production mode is greater than a preset cumulative duration, and then obtain the inlet TDS value or the outlet TDS value.

Images