Connecting valve, return water valve, pressure valve assembly and water supply system

Abstract

The present invention discloses a connection valve, a return water valve, a pressure valve assembly and a water supply system. The return water valve includes a valve body and a pressure relief valve. The valve body is provided with a hot water flow channel, a cold water flow channel, a one-way flow channel and a pressure relief flow channel; the hot water flow channel includes a water inlet cavity, a communication cavity and a water outlet cavity, and the water inlet and the water outlet of the communication cavity are respectively used for communicating with the water inlet cavity and the water outlet cavity; the one-way flow channel communicates the communication cavity with the cold water flow channel; the pressure relief flow channel communicates the water outlet cavity and the one-way flow channel. The pressure relief valve is arranged in the pressure relief flow channel and is adapted to switch between a pressure relief position for opening the pressure relief flow channel and a closed position for closing the pressure relief flow channel. The return water valve of the present invention can solve the problem that the water in the hot water flow channel flows into the cold water flow channel when the water supply system uses the cold water mode.

Description

Technical Field

[0001] The present invention relates to the technical field of zero - cold - water water supply, and particularly relates to a communication valve, a return water valve, a pressure valve assembly and a water supply system. Background Art

[0002] Water supply systems such as water heater water supply systems or wall - hung boiler water supply systems are usually used to provide water for users. Conventional water supply systems generally include structures such as a gas supply device, a cold water pipe, a hot water pipe, a water mixing device, etc.; among them, the gas supply device is connected to the water mixing device through the hot water pipe to use the water mixing device to mix the hot water supplied by the gas supply device and the cold water supplied by the cold water pipe into water with a suitable temperature and supply it to a water outlet device (such as a shower head, a faucet and other water outlet structures) for users to use.

[0003] In the related art, in order to endow a traditional water supply system with a zero - cold - water function, a return water valve is usually configured in the water supply system. This return water valve has a hot water flow channel, a cold water flow channel and a one - way flow channel connecting the hot water flow channel and the cold water flow channel; among them, a one - way valve is configured in the one - way flow channel; a switching valve (such as a one - way valve or a linkage valve, etc.) is configured in the hot water flow channel, and an inlet cavity and an outlet cavity are formed on both sides of the switching valve in the hot water flow channel. Taking the linkage valve as an example, when the water supply system is in the cold water mode of use, the linkage valve is in the initial position, the inlet cavity is connected to the one - way flow channel, and only the water in the cold water pipe passes through the cold water flow channel; when the water supply system is in the zero - cold - water mode of use, the linkage valve moves towards the outlet cavity and switches to the open position, so that the inlet cavity is connected to the one - way flow channel, so that the hot water pipe, the inlet cavity, the one - way flow channel and the cold water pipe form a return water waterway, and then the cold water at the water outlet end can flow back to the hot water supply device for heating to avoid the output of cold water at the initial stage of the water supply system being turned on.

[0004] However, when the pipeline water pressure in the user's home is relatively high, after the water supply system uses the over - cold water mode (such as turning on cold water or flushing the toilet, etc.), due to the pressure - maintaining effect of the outlet cavity of the hot water flow channel in the return water valve, it remains in a relatively high water pressure state. This makes the pressure difference between the outlet cavity and the inlet cavity of the hot water flow channel in the return water valve relatively large, thus locking the linkage valve in the initial position. When using the zero - cold - water mode subsequently, it is difficult for the water pressure in the inlet cavity of the hot water flow channel in the return water valve to offset this pressure difference, and it is also difficult to push the linkage valve to switch to the open position, and thus it is difficult to turn on the zero - cold - water mode. Summary of the Invention

[0005] The main object of the present invention is to propose a return water valve, aiming to solve the problem that after the water supply system uses the cold water mode, the water pressure in the outlet cavity of the hot water flow channel in the return water valve is relatively high, locking the switching valve (such as a one - way valve or a linkage valve, etc.) in the initial position and making it difficult to switch positions subsequently.

[0006] To achieve the above object, the present invention provides a return water valve, which includes a valve body and a pressure relief valve. The valve body is provided with a hot water flow channel, a cold water flow channel, a one-way flow channel and a pressure relief flow channel; the hot water flow channel includes a water inlet cavity, a water outlet cavity and a communication cavity located between the water inlet cavity and the water outlet cavity for installing a switching valve; the one-way flow channel communicates the communication cavity with the cold water flow channel; the pressure relief flow channel communicates the water outlet cavity and the one-way flow channel. The pressure relief valve is arranged in the pressure relief flow channel and is adapted to switch between a pressure relief position where the pressure relief flow channel is conducted and a closed position where the pressure relief flow channel is closed.

[0007] Optionally, the pressure relief flow channel is provided with a pressure relief port communicating with the water outlet cavity; the pressure relief valve includes a pressure relief valve core and a pressure relief reset member; wherein, the pressure relief valve core is arranged opposite to the pressure relief port for opening and closing the pressure relief port; the pressure relief reset member is fixed in the valve body and connected to the pressure relief valve core.

[0008] Optionally, a limiting groove corresponding to and communicating with the pressure relief port is arranged on the side wall of the pressure relief flow channel; the pressure relief valve core is axially movably installed in the limiting groove.

[0009] Optionally, the pressure relief reset member is configured as a pressure relief spring; one end of the pressure relief spring is connected to the pressure relief valve core, and the other end of the pressure relief spring is fixed in the valve body.

[0010] Optionally, the return water valve further includes a pressure regulating member installed on the valve body for connecting and fixing the pressure relief spring, and the pressure regulating member is movable relative to the valve body to adjust the distance between the pressure regulating member and the pressure relief valve core.

[0011] Optionally, the valve body is provided with an installation port for installing the pressure regulating member; the pressure regulating member is in threaded fit with the installation port.

[0012] Optionally, the communication cavity has a water inlet communicating with the water inlet cavity and a water outlet communicating with the water outlet cavity; the switching valve of the return water valve is a linkage valve, and the linkage valve is adapted to switch between an initial position and an open position, wherein: in the initial position, one end of the linkage valve blocks the water outlet, and a gap is formed between the other end of the linkage valve and the water inlet; in the open position, the linkage valve opens both the water inlet and the water outlet.

[0013] Optionally, the linkage valve includes a valve core seat and a valve core; wherein, the valve core seat is arranged in the water outlet cavity for blocking the water outlet; the valve core is arranged in the communication cavity and is linked with the valve core seat, and in the initial position, the linkage valve forms the gap between the valve core and the water inlet.

[0014] Optionally, the valve core seat is provided with a connecting shaft extending towards the water outlet of the communication cavity; the valve core ring is sleeved on the connecting shaft, and the length of the valve core ring sleeved on the connecting shaft is adjustable.

[0015] Optionally, one end of the valve core is provided with a socket hole sleeved with the connecting shaft, and the other end thereof is provided with an adjusting screw hole communicating with the socket hole; the linkage valve further includes an adjusting screw, and the adjusting screw is installed in the adjusting screw hole and is in contact and cooperation with the end face of the connecting shaft.

[0016] Optionally, an annular sealing portion is convexly provided on the outer peripheral wall of the end of the valve core away from the valve core seat, and a gap is formed between the annular sealing portion of the valve core and the water inlet in the initial position.

[0017] Optionally, the linkage valve further includes a gasket, and the gasket is arranged on the lower surface of the valve core seat.

[0018] Optionally, the return water valve further includes a reset member, and the reset member is used to make the linkage valve have a tendency to reset to the initial position.

[0019] Optionally, the return water valve further includes a check valve, and the check valve is arranged in the one-way flow channel to guide the water flow in the hot water flow channel to flow unidirectionally towards the cold water flow channel during return water.

[0020] The present invention further provides a water supply system, and the water supply system includes a hot water supply device, a water mixing device and a return water valve. Wherein, the hot water supply device has a water outlet pipe and a water inlet pipe; the hot water access end of the water mixing device is communicated with the water outlet pipe through a hot water pipe, and the cold water access end of the water mixing device is communicated with the water inlet pipe through a cold water pipe; the hot water flow channel of the return water valve is connected to the hot water pipe, and the cold water flow channel of the return water valve is connected to the cold water pipe. The return water valve includes a valve body and a pressure relief valve. The valve body is provided with a hot water flow channel, a cold water flow channel, a one-way flow channel and a pressure relief flow channel; the hot water flow channel includes a water inlet cavity, a water outlet cavity and a communication cavity located between the water inlet cavity and the water outlet cavity for installing a switching valve; the one-way flow channel communicates the communication cavity with the cold water flow channel; the pressure relief flow channel communicates the water outlet cavity and the one-way flow channel. The pressure relief valve is arranged in the pressure relief flow channel, and the pressure relief valve is adapted to switch between a pressure relief position for conducting the pressure relief flow channel and a closed position for closing the pressure relief flow channel.

[0021] Optionally, the hot water supply device is a gas water heater or a gas wall-mounted boiler or an electric water heater.

[0022] The technical solution of the present invention is provided with a hot water flow channel, a cold water flow channel, a one-way flow channel and a pressure relief flow channel in the return water valve; wherein, the hot water flow channel has a water inlet cavity, a communication cavity and a communication cavity located between the water inlet cavity and the water outlet cavity for installing a switch valve; the one-way flow channel communicates the communication cavity with the cold water cavity; the pressure relief flow channel communicates the water outlet cavity with the one-way flow channel, and a pressure relief valve is arranged in the pressure relief flow channel. The pressure relief valve is adapted to switch between a pressure relief position for conducting the pressure relief flow channel and a closed position for closing the pressure relief flow channel. Thus, when the water pressure in the water outlet cavity of the hot water flow channel is relatively high, the water outlet cavity is pressure-relieved through the pressure relief valve, ensuring that the pressure of the water outlet cavity is not too high, and ensuring that the linkage valve can be locked in the cold water mode and can be better opened when switching to the zero cold water mode (please refer to the following description for details). BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0024] Figure 1 Structural schematic diagram of an embodiment of the water supply system of the present invention;

[0025] Figure 2 For Figure 1 Structural schematic diagram of an embodiment of the return water valve in;

[0026] Figure 3 For Figure 2 Enlarged view of part A in;

[0027] Figure 4 For Figure 2 Enlarged view of part B in;

[0028] Figure 5 For Figure 2 Schematic diagram of the state of the return water valve in the cold water mode in;

[0029] Figure 6 For Figure 2 Schematic diagram of the state of the return water valve in the hot water mode in;

[0030] Figure 7 For Figure 2 Schematic diagram of the state of the return water valve in the zero cold water mode in;

[0031] Figure 8 Structural schematic diagram of another embodiment of the water supply system of the present invention;

[0032] Figure 9 ForFigure 8 Schematic diagram of the state of the medium pressure valve assembly in the cold water mode;

[0033] Figure 10 For Figure 9 Schematic diagram of the structure of an embodiment of the connecting valve in the medium;

[0034] Figure 11 For Figure 10 Enlarged view at C in the medium;

[0035] Figure 12 For Figure 10 Enlarged view at D in the medium;

[0036] Figure 13 For Figure 9 Schematic diagram of the state of the pressure valve assembly in the medium in the hot water mode;

[0037] Figure 14 For Figure 9 Schematic diagram of the state of the pressure valve assembly in the medium in the zero cold water mode;

[0038] Figure 15 Schematic diagram of the structure of another embodiment of the water supply system of the present invention;

[0039] Figure 16 For Figure 15 Schematic diagram of the state of the pressure valve assembly in the medium in the cold water mode.

[0040] Explanation of the reference numerals in the drawings:

[0041] Table 1: Explanation of the reference numerals in the attached Figures 1 to 10 of

[0042] Label Name Label Name 100 Valve body 322 Socket hole 110 Hot water runner 323 Adjusting screw hole 111 Water inlet cavity 330 Adjusting screw 112 Communication cavity 340 Gasket 113 Water outlet cavity 301 Clearance 120 Cold water runner 302 Open gap 130 One-way runner 400 Reset part / Reset spring 140 Cover 500 Water regulating valve 150 Pressure relief runner 700 Pressure relief valve 151 Pressure relief port 710 Pressure relief valve core 152 Limit groove 720 Pressure relief reset part / Pressure relief spring 153 Installation port 10 Return water valve 160 Pressure regulating part 20 Hot water supply device 200 Check valve 30 Water mixing device 300 Linkage valve 40 Water outlet device 310 Valve core seat 50 Hot water pipe 311 Connecting shaft 60 Cold water pipe 320 Valve core 70 Circulating water pump 321 Annular sealing part

[0043] Table 2: Explanation of the reference numerals in the attached Figures 8 to 16 of

[0044]

[0045]

[0046] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Detailed implementation manners

[0047] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0048] It should be noted that if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and should not be construed as indicating or implying their 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 at least one such feature.

[0049] In addition, the meaning of "and / or" appearing throughout the text is that it includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, or solution B, or the solution where both A and B are satisfied simultaneously.

[0050] Water supply systems such as water heater water supply systems or wall-mounted boiler water supply systems are usually used to provide water for users. Conventional water supply systems generally include structures such as a gas supply device, a cold water pipe, a hot water pipe, and a mixing device; among them, the gas supply device is connected to the mixing device through the hot water pipe to use the mixing device to mix the hot water supplied by the gas supply device and the cold water supplied by the cold water pipe into water with a suitable temperature and supply it to the water outlet device (such as a shower head, a faucet, etc. water outlet structures) for users to use.

[0051] In the related art, in order to enable the traditional water supply system to have the zero cold water function, a return water valve is usually configured in the water supply system. This return water valve has a hot water flow channel, a cold water flow channel, and a one-way flow channel connecting the hot water flow channel and the cold water flow channel; among them, a one-way valve is configured in the one-way flow channel; a switch valve (such as a one-way valve or a linkage valve, etc.) is configured in the hot water flow channel, and an inlet cavity and an outlet cavity are formed on both sides of the switch valve in the hot water flow channel. Taking the linkage valve as an example, when the water supply system is in the cold water mode of use, the linkage valve is in the initial position, the inlet cavity is connected to the one-way flow channel, and only the water from the cold water pipe passes through the cold water flow channel; while when the water supply system is in the zero cold water mode of use, the linkage valve moves towards the outlet cavity and switches to the open position, so that the inlet cavity is connected to the one-way flow channel, so that the hot water pipe, the inlet cavity, the one-way flow channel, and the cold water pipe are constructed into a return water waterway, and then the cold water at the water outlet end can flow back to the hot water supply device for heating to avoid the output of cold water at the initial stage of the water supply system being turned on.

[0052] However, when the pipeline water pressure in the user's home is relatively high, after the water supply system uses the super cold water mode (such as turning on cold water or flushing the toilet, etc.), due to the pressure maintaining effect of the outlet cavity of the hot water flow channel, it will remain in a relatively high water pressure state. This makes the pressure difference between the outlet cavity and the inlet cavity of the hot water flow channel relatively large, thus locking the linkage valve in the initial position. When using the zero cold water mode subsequently, it is difficult for the water pressure in the inlet cavity of the hot water flow channel in the return water valve to offset this pressure difference, and it is also difficult to push the linkage valve to switch it to the open position, and thus it is difficult to turn on the zero cold water mode.

[0053] Based on this, the present invention provides a return water valve and a water supply system including the return water valve. The return water valve aims to solve the problem that after the water supply system uses the cold water mode, the water pressure in the water outlet cavity of the hot water flow channel in the return water valve is relatively high, locking the switching valve (such as a one-way valve or a linkage valve, etc.) in the initial position, and it is difficult to switch positions subsequently.

[0054] Figures 1 to 7 FIG. is a schematic diagram of an embodiment of the return water valve and the water supply system including the return water valve proposed by the present invention. The Figures 1 to 7 description of the reference numerals of the attached drawings can be seen in Table 1 above. The return water valve 10 is used to be connected to the cold water pipe 50 and the hot water pipe 60 of the water supply system to form a return water path in the water supply system, so that the water supply system has a zero cold water mode. The return water valve 10 can solve the problem that after the water supply system uses the cold water mode, the water pressure in the water outlet cavity of the hot water flow channel in the return water valve is relatively high, locking the switching valve (such as a one-way valve or a linkage valve, etc.) in the initial position, and it is difficult to switch positions subsequently.

[0055] Please refer to Figure 2 and Figure 3 In an embodiment of the return water valve of the present invention, the return water valve 10 includes a valve body 100 and a linkage valve 300. The valve body 100 is provided with a hot water flow channel 110, a cold water flow channel 120, a one-way flow channel 130 and a pressure relief flow channel 150; the hot water flow channel 110 includes a water inlet cavity 111, a communication cavity 112 and a water outlet cavity 113 located between the water inlet cavity 111 and the communication cavity 112 for installing the switching valve 300; the one-way flow channel 130 communicates the communication cavity 112 with the cold water flow channel 120; the pressure relief flow channel 150 communicates the water outlet cavity 113 and the one-way flow channel 130. A pressure relief valve 700 is provided in the pressure relief flow channel 150, and the pressure relief valve 700 is adapted to switch between a pressure relief position where the pressure relief flow channel 150 is conducted and a closed position where the pressure relief flow channel 150 is closed.

[0056] Specifically, the switching valve 300 of the return water valve 10 is arranged in the communication cavity 112 of the hot water flow channel 110, and the switching valve 300 can be a valve structure with a switching function such as a linkage valve or a one-way valve. Specifically, in this embodiment, the switching valve 300 is a linkage valve 300. The linkage valve 300 is arranged in the hot water flow channel 110, and the linkage valve 300 is adapted to switch between an initial position where the water inlet 112a and the water outlet 112b are closed and an open position where the water inlet 112a and the water outlet 112b are opened.

[0057] The one-way flow channel 130 of the return water valve 10 is adapted to guide the water flow to flow unidirectionally from the hot water flow channel 110 to the cold water flow channel 120, and reverse flow is not allowed. To achieve the unidirectional flow of the water flow in the one-way flow channel 130, a one-way valve 200 can be arranged in the one-way flow channel 130. The one-way valve 200 can have various structural types, and various types of one-way valves are relatively common in the current market, and will not be listed one by one here. Optionally, the one-way valve 200 includes a one-way valve core 210 movably arranged in the one-way flow channel 130, and a return spring 220 connecting the one-way valve core 210 and the valve body 100. The one-way valve 200 has an open position for opening the one-way flow channel 130, and a closed position for being reset to close the one-way flow channel 130 under the drive of the return spring 220.

[0058] The linkage valve 300 is installed in the hot water flow channel 110 of the return water valve 10. The linkage valve 300 is adapted to move from the initial position to the open position when the difference between the water pressure in the water inlet cavity 111 and the water pressure in the water outlet cavity 113 of the hot water flow channel 110 increases, and it has the following two meanings: 1) When the difference between the water pressure in the water inlet cavity 111 and the water pressure in the water outlet cavity 113 starts to increase, the linkage valve 300 moves from the initial position to the open position; 2) When the difference between the water pressure in the water inlet cavity 111 and the water pressure in the water outlet cavity 113 increases to a preset value, the linkage valve 300 moves from the initial position to the open position. In a specific embodiment, the above two design methods can be selected according to actual needs.

[0059] The hot water flow channel 110 of the return water valve 10 is also provided with a first interface 101 at the entrance of its water inlet cavity 111, and a second interface 102 at the outlet of its water outlet cavity 113; the cold water flow channel 120 of the return water valve 10 is provided with a third interface 103 at its entrance, and a fourth interface 104 at its outlet. When the return water valve 10 is assembled into the water supply system, the first interface 101 of the return water valve 10 is connected to the hot water supply device 20 through the hot water pipe 50, and the second interface 102 is connected to the hot water access end 31 of the mixing device 30; the third interface 103 is connected to the cold water source (such as a tap water pipeline) through the cold water pipe 60, and the fourth interface 104 is connected to the cold water access end 32 of the mixing device 30. In addition, the water supply system is also equipped with a circulation water pump 70, and the circulation water pump 70 is used to connect the third interface 103 and the hot water supply device 20 for sucking cold water. The circulation water pump 70 can be arranged on the pipeline between the heat exchanger of the hot water supply device 20 and the cold water pipe 60. Specifically, the circulation water pump 70 is arranged on the water inlet pipe 21 of the hot water supply device 20.

[0060] Since the water supply system is equipped with the return water valve 10, the water supply system has at least three working modes: cold water mode, hot water mode and zero cold water mode. The working principles of these three working modes will be explained below, and for details, please refer to the following text.

[0061] Please refer to Figure 1 and Figure 5 When the water supply system uses the cold water mode, the return water valve 10 is in the initial position; at this time, the pressure of the cold water flow channel 120 of the return water valve 10 decreases, and the water flow in the cold water pipe 60 flows from the cold water flow channel 120 to the cold water access end 32 of the mixing device 30, and then is supplied to the water outlet device 40 through the output end of the mixing device 30. At this time, the one-way valve core 210 of the one-way valve 200 is in the closed position under the tension of the return spring 220.

[0062] In the above cold water mode, since the pressure of the cold water pipe 60 decreases, the pressure of the cold water flow channel 120 of the return water valve 10 will decrease. The water inlet cavity 111 of the hot water flow channel 110 of the return water valve 10 is connected to the hot water pipe 50, and the pressure of the hot water pipe 50 is higher than that of the cold water pipe 60. The water flow in the hot water pipe 50 has a tendency to enter the cold water flow channel 120 from the water inlet cavity 111, thus having a tendency to push the linkage valve 300 upward; in addition, the water outlet cavity 113 of the hot water flow channel 110 is connected to the hot water access end 31 of the mixing device 30, and the hot water access end 31 is in the closed state in this mode, so the water outlet cavity 113 is in a pressure-holding state. The pressure reduction of the cold water flow channel 120 also causes a pressure difference between the water outlet cavity 113 of the hot water flow channel 110 and the cold water flow channel 120. Therefore, the water pressure in the water outlet cavity 113 also has a tendency to push down the linkage valve 300, thus offsetting the upward thrust of the water inlet cavity 111 of the hot water flow channel 110 on the linkage valve 300, restricting the upward movement and opening of the linkage valve 300, and keeping the linkage valve 300 in the initial position.

[0063] Please refer to Figure 1 and Figure 6 When the water supply system uses the hot water mode, the pressure of the water outlet cavity 113 of the hot water flow channel 110 in the return water valve 10 decreases and drops below the pressure of the water inlet cavity 111, increasing the pressure difference between the pressure in the water inlet cavity 111 and the pressure in the water outlet cavity 113. The water flow in the water inlet cavity 111 pushes the linkage valve 300 upward, causing the linkage valve 300 to move to the open position. Thus, the water flow in the hot water pipe 50 flows from the hot water flow channel 110 through the water inlet cavity 111 to the water outlet cavity 113, and then enters the mixing device 30 from the hot water access end 31 of the mixing device 30 and is supplied to the water outlet device 40 through the outlet of the mixing device 30. The flow rate of the hot water pipe 50 increases, and the hot water supply device 20 starts to prepare hot water. At this time, the one-way valve core 210 of the one-way valve 200 is in the closed position under the tension of the return spring 220.

[0064] Please refer to Figure 1 and Figure 7, when the water supply system uses the zero - cold - water mode, the circulation pump 70 is turned on and pushes the water flow to move, causing the water pressure in the hot - water pipe 50 to increase. As a result, the pressure in the water - inlet chamber 111 of the hot - water flow channel 110 in the return - water valve 10 increases, which then pushes the linkage valve 300 to move upward. When at rest, the pressure in the water - inlet chamber 111 and the water - outlet chamber 113 of the return - water valve 10 is balanced. At this time, the linkage valve 300 reaches the open position, and the linkage valve 300 opens the water - inlet port 112a of the communication chamber 112. A large amount of water flow in the hot - water pipe 50 enters the one - way flow channel 130, thereby overcoming the acting force of the return spring 220 to push open the one - way valve 200. The water flows through the one - way flow channel 130 into the cold - water flow channel 120, and then returns to the hot - water supply device 20 through the cold - water pipe 60 for circulating heating.

[0065] As described above, when using the cold - water mode, a water - hammer phenomenon will occur during the process of switching on the cold water. This phenomenon will cause the pressure in the water - inlet chamber 111 of the hot - water flow channel 110 in the return - water valve 10 to increase (increase by about 0.2 - 0.3 MPa). The pressure difference between the water - inlet chamber 111 and the water - outlet chamber 113 of the hot - water flow channel 110 has a tendency to push the linkage valve 300 to move upward, thereby squeezing the water flow in the water - outlet chamber 113, causing the water pressure in the water - outlet chamber 113 to increase. Furthermore, the water pressure in the water - outlet chamber 113 pushes open the pressure - relief valve 700, causing the pressure - relief valve 700 to move to the pressure - relief position, making the pressure - relief flow channel 150 conductive. A small part of the water flow in the water - outlet chamber 113 is discharged to the one - way flow channel 130 through the pressure - relief flow channel 150, thereby realizing the pressure relief of the water - outlet chamber 113 to ensure that the pressure in the water - outlet chamber 113 is not too high and there is a certain pressure difference. In this way, it can be ensured that when the cold - water mode is turned on, the linkage valve 300 can be better maintained in the initial position without opening, preventing the problem of water cross - flow after the cold - water opening operation. After switching the working mode later, the linkage valve 300 can be easily opened.

[0066] Due to the existence of the pressure - relief valve 700, even if a water - hammer phenomenon occurs when switching on the cold water in the cold - water mode, the pressure in the water - outlet chamber 113 of the hot - water flow channel 110 will not be too high. Therefore, as Figure 6 shown, after the zero - cold - water mode is turned on, the circulation pump 70 will push the water flow to move, causing the pressure in the water - inlet chamber 111 of the return - water valve 10 to increase. The pressure generated by the circulation pump 70 in the water - inlet chamber 111 of the return - water valve 10 can better offset the pressure difference, and then push the linkage valve 300 to move upward so that the linkage valve 300 can be normally opened, realizing the water - circulation pre - heating. This can effectively reduce the situation where after the zero - cold - water mode is turned on, the linkage valve 300 is locked in the initial position because the water - outlet chamber 113 of the hot - water flow channel 110 in the return - water valve 10 maintains a high pressure, making it difficult for the linkage valve 300 to be normally opened.

[0067] The technical solution of the present invention is provided with a hot water flow channel 110, a cold water flow channel 120, a one-way flow channel 130 and a pressure relief flow channel 150 in the return water valve 10; wherein, the hot water flow channel 110 has a water inlet cavity 111, a communication cavity 112 and a water outlet cavity 113 located between the water inlet cavity 111 and the communication cavity 112 for installing the switching valve 300. The water inlet 112a and the water outlet 112b of the communication cavity 112 are respectively used to communicate with the water inlet cavity 111 and the water outlet cavity 113; the one-way flow channel 130 communicates the communication cavity 112 and the cold water flow channel 120; the pressure relief flow channel 150 communicates the water outlet cavity 113 and the one-way flow channel 130, and a pressure relief valve 700 is arranged in the pressure relief flow channel 150. The pressure relief valve 700 is adapted to switch between a pressure relief position for conducting the pressure relief flow channel 150 and a closed position for closing the pressure relief flow channel 150. Thus, when the water pressure in the water outlet cavity 113 of the hot water flow channel 110 is relatively high, the water outlet cavity 113 is pressure-relieved through the pressure relief valve 700 to ensure that the pressure in the water outlet cavity 113 is not too high, ensuring that the linkage valve 300 can be locked in the cold water mode and can be better opened when switched to the zero cold water mode (please refer to the foregoing description for details).

[0068] Please refer to Figure 2 and Figure 3 In an embodiment, the valve body 100 is further provided with a pressure relief port 151 for communicating the water outlet cavity 113 and the pressure relief flow channel 150; the pressure relief valve 700 includes a pressure relief valve core 710 and a pressure relief reset member 720. Among them, the pressure relief valve core 710 is disposed opposite to the pressure relief port 151 for opening and closing the pressure relief port 151; the pressure relief reset member 720 is fixed in the valve body 100 and is connected to the pressure relief valve core 710.

[0069] Specifically, the pressure relief reset member 720 has elasticity. When the pressure relief valve 700 is in the closed position, the tension of the pressure relief reset member 720 confines the pressure relief valve core 710 in the position of closing the pressure relief port 151; when the water pressure in the water outlet cavity 113 is greater than the tension of the pressure relief reset member 720, the water flow in the water outlet cavity 113 will push open the pressure relief valve core 710, causing the pressure relief port 151 to open. At this time, the pressure relief reset member 720 is compressed and stores elastic potential energy, which is used to drive the pressure relief valve core 710 to return to the closed position after the pressure relief is completed.

[0070] As for the specific structural type of the pressure relief reset member 720, there can be various structural types. For example, but not limited to, the pressure relief reset member 720 can be a spring, a spring sheet or a tension spring and other elastic structures. Specifically in this embodiment, the pressure relief reset member 720 is configured as a pressure relief spring 720. One end of the pressure relief spring 720 is fixed in the valve body 100, and the other end of the pressure relief spring 720 is connected to the pressure relief valve core 710.

[0071] Please refer to Figure 2 and Figure 3, in one embodiment, to ensure that the pressure relief valve core 710 accurately moves to switch the pressure relief port 151, a limiting groove 152 communicating with the pressure relief port 151 is provided on the side wall of the pressure relief flow channel 150; the pressure relief valve core 710 is axially movably installed in the limiting groove 152. Since the pressure relief valve core 710 is limited to move within the limiting groove 152, the pressure relief valve core 710 is always aligned with the pressure relief port 151, so that the pressure relief valve core 710 accurately switches the pressure relief port 151 during the movement process, avoiding the situation where the pressure relief valve core 710 is misaligned with the pressure relief port 151.

[0072] Please also refer to Figure 2 and Figure 3 , in one embodiment, considering that the water pressure in different user households is different, the degree of pressure relief required for the water outlet cavity is also different. Therefore, to make the return water valve 10 applicable to the water pressure of different user households, optionally, the return water valve 10 further includes a pressure regulating member 160 installed on the valve body 100 for the pressure relief spring 720 to be connected and fixed. The pressure regulating member 160 is movable relative to the valve body 100 to adjust the distance between the pressure regulating member 160 and the pressure relief valve core 710.

[0073] Specifically, since the two ends of the pressure relief reset member 720 are respectively connected between the pressure relief valve core 710 and the pressure regulating member 160, therefore, adjusting the distance between the pressure regulating member 160 and the pressure relief valve core 710 can also adjust the tightness of the pressure relief spring 720 squeezed by the pressure regulating member 160 and the pressure relief valve core 710, so that the pressure relief spring 720 has different pressure relief elastic forces, and further makes the pressure relief valve have different pressure relief values. For example, reducing the distance between the pressure regulating member 160 and the pressure relief valve core 710 makes the pressure relief spring 720 more compressed, so that the pressure relief spring 720 has a greater pressure relief elastic force. At this time, the water outlet cavity 111 needs to have a higher water pressure to overcome the pressure relief elastic force of the pressure relief spring 720 to push the pressure relief valve core 710 to the pressure relief position; vice versa. Therefore, when the water pressure in the user's household is relatively high, the distance between the pressure regulating member 160 and the pressure relief valve core 710 can be appropriately reduced. Conversely, the distance between the pressure regulating member 160 and the pressure relief valve core 710 can be appropriately increased.

[0074] Furthermore, the valve body 100 is provided with an installation port 153 for installing the pressure regulating member 160; the pressure regulating member 160 is in threaded fit with the installation port 153. During adjustment, by rotating the pressure regulating member 160, the pressure regulating member 160 can be made to move relatively closer to or farther away from the pressure relief valve core 710, thereby adjusting the distance between the two.

[0075] Please refer to Figure 2 and Figure 4Based on any of the above embodiments, the switch valve 300 of the water return valve 10 is a linkage valve 300, and the linkage valve 300 is suitable for switching between an initial position and an open position, wherein: in the initial position, one end of the linkage valve 300 blocks the water outlet 112b, and a gap 301 is formed between the other end of the linkage valve 300 and the water inlet 112a; in the open position, the linkage valve 300 opens both the water inlet 112a and the water outlet 112b. Specifically, the linkage valve 300 covers but does not completely block the water inlet 112a of the connecting cavity 112 in the initial position, so that a narrow gap 301 is formed between the linkage valve 300 and the water inlet 112a (it should be noted that the gap is not enough to open the water inlet 112a).

[0076] When water hammer occurs in the cold water mode, a small portion of the water flowing in the water inlet chamber 111 of the hot water flow channel 110 will enter the connecting chamber 112 from the gap 301, thereby relieving the pressure in the water inlet chamber 111 and reducing the situation where the pressure in the water inlet chamber 111 is greater than the pressure in the water outlet chamber 113, so that the upward force exerted by the water flow in the water inlet chamber 111 on the linkage valve 300 is basically the same as the downward force exerted by the water flow in the water outlet chamber 113 on the linkage valve 300, thereby limiting the water flow in the water inlet chamber 111 from pushing the linkage valve 300 upward and keeping the linkage valve 300 in the initial position, thereby greatly reducing the amount of water leaking from the hot water pipe 50 to the connecting chamber 112.

[0077] This small amount of water is not enough to push open the one-way valve 200, so that the water flow in the hot water pipe 50 will not flow to the cold water flow channel 120 through the one-way flow channel 130 in large quantities. This amount of water is much smaller than the flow rate of the hot water supply device 20 when it is started, thereby solving the problem of water hammer in the cold water mode causing the water flow in the hot water pipe 50 to flow to the cold water flow channel 120, effectively reducing the situation where the hot water supply device 20 is accidentally started due to the increase in the flow rate of the hot water pipe 50, and realizing that the hot water supply device 20 does not start when the cold water is turned on. In other words, the water inlet chamber 111 can be depressurized through the gap 301, and the water outlet chamber 113 can be depressurized through the pressure relief valve 700.

[0078] See also Figure 2 and Figure 4 In one embodiment, for the structure of the linkage valve 300, the linkage valve 300 includes a valve core seat 310 and a valve core 320; wherein the valve core seat 310 is arranged in the water outlet chamber 113, and is used to block the water outlet 112b of the connecting chamber 112; the valve core 320 is arranged in the connecting chamber 112, and is linked with the valve core seat 310. In the initial position, the linkage valve 300 forms a gap 301 between the valve core 320 and the water inlet 112a of the connecting chamber 112.

[0079] Specifically, the valve core seat 310 and the valve core 320 of the linkage valve 300 are linked in the same direction. In the initial position, the linkage valve 300 blocks the water outlet 112b of the communication cavity 112 through the valve core seat 310, and a gap 301 is formed between the valve core 320 of the linkage valve 300 and the water inlet 112a of the communication cavity 112. When the linkage valve 300 moves upward to the open position under the action of the water pressure difference on both sides, the valve core seat 310 of the linkage valve 300 opens the water outlet 112b of the communication cavity 112, and the valve core 320 of the linkage valve 300 opens the water inlet 112a of the communication cavity 112. Vice versa.

[0080] As for the way of the linkage setting of the valve core seat 310 and the valve core 320 of the linkage valve 300, there can be various design schemes. For example, in one embodiment, the valve core seat 310 is provided with a connecting shaft 311 extending toward the water outlet 112b of the communication cavity 112; the valve core 320 is sleeved on the connecting shaft 311. Here, it is considered that there may be structural design or assembly errors in the design process of the return water valve 10, so that after the linkage valve 300 is installed in the hot water flow channel 110 of the return water valve 10, a zero gap or an excessive gap may occur between the valve core 320 of the linkage valve 300 and the water inlet 112a of the communication cavity 112 of the hot water flow channel 110. To reduce the occurrence of this situation, optionally, the length of the valve core 320 sleeved on the connecting shaft 311 is set to be adjustable, so that the size of the gap 301 formed between the valve core 320 and the water inlet 112a of the communication cavity 112 can be adjusted.

[0081] Specifically, please refer to Figure 4 , Figure 4 where h1 represents the length of the valve core 320 sleeved on the connecting shaft 311; h2 represents the size of the gap 301 between the valve core 320 and the water inlet 112a of the communication cavity 112. The size of the gap 301 refers to the width size in the axial direction of the connecting shaft 311. By adjusting the length of the upper end of the valve core 320 sleeved on the connecting shaft 311, the distance between the lower end of the valve core 320 and the water inlet 112a of the communication cavity 112 can be adjusted, so as to adjust the size of the gap 301 formed between the valve core 320 and the water inlet 112a of the communication cavity 112.

[0082] For example, when the length of the valve core 320 sleeved on the connecting shaft 311 is reduced, the lower end of the valve core 320 will approach the water inlet 112a of the communication cavity 112, so as to reduce the distance between the lower end of the valve core 320 and the water inlet 112a of the communication cavity 112, and reduce the gap 301 between the valve core 320 and the water inlet 112a of the communication cavity 112 (that is, when h1 is reduced, h2 is also reduced).

[0083] Please also refer to Figure 2 and Figure 4, as for the way to realize the adjustable length of the valve core 320 sleeved on the connecting shaft 311, there can be various design methods. In one embodiment, one end of the valve core 320 is provided with a socket hole 322 sleeved on the connecting shaft 311, and the other end is provided with an adjusting screw hole 323 communicating with the socket hole 322; the valve core 320 further includes an adjusting screw 330, and the adjusting screw 330 is installed in the adjusting screw hole 323 and is in contact and cooperation with the end face of the connecting shaft 311.

[0084] When it is necessary to adjust the size of the gap 301, rotate the adjusting screw 330. Since the inner end face of the adjusting screw 330 is in contact with and abuts against the end face of the connecting shaft 311, the relative positions of the adjusting screw 330 and the connecting shaft 311 remain unchanged, while the valve core 320 threadedly engaged with the adjusting screw 330 expands and contracts axially relative to the connecting shaft 311, thereby changing the length of the valve core 320 sleeved on the connecting shaft 311 and realizing the adjustable length of the valve core 320 sleeved on the connecting shaft 311.

[0085] Certainly, in another embodiment, an internal thread can also be directly provided on the inner peripheral surface of the socket hole 322 of the valve core 320, and an external thread can be provided on the outer peripheral surface of the connecting shaft 311, so that the internal thread of the valve core 320 is engaged with the external thread of the connecting shaft 311, thereby directly rotating the valve core 320 to change the length of the valve core 320 sleeved on the lower shaft section 332, and further realizing the adjustable length of the valve core 320 sleeved on the connecting shaft 311.

[0086] As for the position of the gap 301 formed between the valve core 320 and the water inlet 112a of the communication cavity 112, optionally, an annular sealing portion 321 is convexly provided on the outer peripheral wall of one end of the valve core 320 away from the valve core seat 310. In the initial position, a gap 301 is formed between the annular sealing portion 321 and the water inlet 112a of the communication cavity 112. It can be understood that the valve core 320 covers but does not completely block the water inlet 112a of the communication cavity 112 through the annular sealing portion 321, so as to form a narrow gap 301 between the annular sealing portion 321 and the water inlet 112a.

[0087] Please refer to Figure 2 , based on any of the above embodiments, the return water valve 10 further includes a reset member 400, and the reset member 400 is used to make the linkage valve 300 have a tendency to reset to the initial position. Thus, after the hot water use of the water outlet device 40 ends or after the hot water in the hot water pipe 50 is preheated, etc., the reset member 400 can drive the linkage valve 300 to reset to the initial position. The reset member 400 can also be an elastic structure such as a spring, a spring piece or a tension spring

[0088] Optionally, the reset member 400 is configured as a reset spring 400. One end of the reset spring 400 is fixed within the water outlet chamber 113, and the other end of the reset spring 400 is connected to the linkage valve 300. The reset spring 400 is used to give the core of the linkage valve 300 a tendency to reset to the initial position. Thus, on the one hand, after the hot water usage of the water outlet device 40 ends or after preheating the hot water in the hot water pipe 50, etc., the reset spring 400 can drive the linkage valve 300 to reset to the initial position; on the other hand, the reset spring 400 can also limit the linkage valve 300 to the initial position to ensure the usage stability of the linkage valve 300 at the initial position.

[0089] Please refer to Figure 2 , in one embodiment, the linkage valve 300 further includes a gasket 340, and the gasket 340 is disposed on the lower surface of the valve core seat 310. Specifically, the lower surface of the valve core seat 310 is convexly provided with a mounting portion surrounding the outer circumference of the connecting shaft 311; the gasket 340 is sleeved on the mounting portion. The gasket 340 can be made of a material such as rubber that has elasticity and a better sealing effect, so as to seal the gap between the valve core seat 310 and the water outlet 112b of the communication chamber 112 when the linkage valve 300 is in the initial position.

[0090] Please refer to Figure 2 , based on any of the above embodiments, the return water valve 10 further includes a water regulating valve 500. The water regulating valve 500 is installed in the cold water flow channel 120 through the installation port for regulating the water flow rate in the cold water flow channel 120. Optionally, the hot water flow channel 110 is a straight flow channel, and / or the cold water flow channel 120 is a straight flow channel, and / or the one-way flow channel 130 is a straight flow channel. Of course, in other embodiments, any one or more of the hot water flow channel 110, the cold water flow channel 120, and the one-way flow channel 130 can also be set as an L-shaped flow channel.

[0091] Please refer to Figure 1 , the present invention further provides a water supply system, and the water supply system includes a hot water supply device 20, a water mixing device 30, and a return water valve 10. Among them, the hot water supply device 20 has a water outlet pipe 22 and a water inlet pipe 21; the hot water access end 31 of the water mixing device 30 is communicated with the water outlet pipe 22 through a hot water pipe 50, and the cold water access end 32 of the water mixing device 30 is communicated with the water inlet pipe 21 through a cold water pipe 60; the hot water flow channel 110 of the return water valve 10 is connected to the hot water pipe 50, and the cold water flow channel 120 of the return water valve 10 is connected to the cold water pipe 60. The specific structure of the return water valve 10 refers to the above embodiments. Since this water supply system adopts all the technical solutions of the above all embodiments, it also has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated here one by one.

[0092] Optionally, the water supply system further includes a water outlet device 40, and the water outlet device 40 is connected to the output end 33 of the water mixing device 30. The number of the water outlet devices 40 can be one, two or more. When there are two or more water outlet devices 40, a return water valve 10 can be configured for each water outlet device 40, or a return water valve 10 can be configured only for the water outlet device 40 arranged at the farthest end. Of course, in other embodiments, the water outlet device 40 can also be provided by the user himself.

[0093] As for the specific type of the hot water supply device 20, the hot water supply device 20 can be selected as a gas water heater, a gas wall-mounted boiler or an electric water heater, and can be reasonably configured according to market or user needs, and no specific limitation is set here.

[0094] Since the water supply system is configured with a return water valve 10, the water supply system has at least three working modes: a cold water mode, a hot water mode and a zero cold water mode. The water supply system can switch between the cold water mode, the hot water mode and the zero cold water mode to realize functions such as supplying cold water, supplying hot water or zero cold water. For the convenience of understanding, the working principles of these three working modes will be explained below. For details, please refer to the following text.

[0095] Please refer to Figure 1 and Figure 5 , when the water supply system uses the cold water mode, the return water valve 10 is in the initial position; at this time, the pressure of the cold water flow channel 120 of the return water valve 10 decreases, and the water flow in the cold water pipe 60 flows from the cold water flow channel 120 to the cold water access end 32 of the water mixing device 30, and then is supplied to the water outlet device 40 through the output end of the water mixing device 30. At this time, the one-way valve core 210 of the one-way valve 200 is in the closed position under the tension of the return spring 220.

[0096] In the above cold water mode, since the pressure of the cold water pipe 60 decreases, the pressure of the cold water flow channel 120 of the return water valve 10 will decrease. The inlet cavity 111 of the hot water flow channel 110 of the return water valve 10 is connected to the hot water pipe 50, and the pressure of the hot water pipe 50 is higher than that of the cold water pipe 60. The water flow in the hot water pipe 50 has a tendency to enter the cold water flow channel 120 from the inlet cavity 111, so as to have a tendency to push the linkage valve 300 upward; in addition, the outlet cavity 113 of the hot water flow channel 110 is connected to the hot water access end 31 of the water mixing device 30, and the hot water access end 31 is in the closed state in this mode, so the outlet cavity 113 is in a pressure maintaining state. The pressure reduction of the cold water flow channel 120 also causes a pressure difference between the outlet cavity 113 of the hot water flow channel 110 and the cold water flow channel 120. Therefore, the water pressure of the outlet cavity 113 also has a tendency to push down the linkage valve 300, thus offsetting the upward thrust of the inlet cavity 111 of the hot water flow channel 110 on the linkage valve 300, restricting the upward movement of the linkage valve 300 to open, and keeping the linkage valve 300 in the initial position.

[0097] Please refer to Figure 1 and Figure 6 When the water supply system uses the hot water mode, the pressure in the water outlet chamber 113 of the hot water flow channel 110 in the return water valve 10 decreases and drops below the pressure in the water inlet chamber 111, increasing the pressure difference between the pressure in the water inlet chamber 111 and the pressure in the water outlet chamber 113. The water flow in the water inlet chamber 111 pushes the linkage valve 300 upwards, causing the linkage valve 300 to move to the open position. Thus, the water flow in the hot water pipe 50 flows from the hot water flow channel 110 through the water inlet chamber 111 to the water outlet chamber 113, and then enters the mixing device 30 from the hot water access end 31 of the mixing device 30 and is supplied to the water outlet device 40 through the outlet of the mixing device 30. The flow rate of the hot water pipe 50 increases, and the hot water supply device 20 starts to prepare hot water. At this time, the one-way valve core 210 of the one-way valve 200 is in the closed position under the tension of the return spring 220.

[0098] Please refer to Figure 1 and Figure 7 When the water supply system uses the zero cold water mode, the circulation water pump 70 is turned on and pushes the water flow to increase the water pressure in the hot water pipe 50. The pressure in the water inlet chamber 111 of the hot water flow channel 110 in the return water valve 10 increases, thereby pushing the linkage valve 300 upwards. When stationary, the pressures in the water inlet chamber 111 and the water outlet chamber 113 of the return water valve 10 are equal. At this time, the linkage valve 300 reaches the open position, and the linkage valve 300 opens the water inlet 112a of the communication chamber 112. A large amount of the water flow in the hot water pipe 50 enters the one-way flow channel 130, thereby overcoming the acting force of the return spring 220 to push open the one-way valve 200. The water flow passes through the one-way flow channel 130 and enters the cold water flow channel 120, and then returns to the hot water supply device 20 through the cold water pipe 60 from the cold water flow channel 120 for circulating heating.

[0099] As described above, when using the cold water mode, a water hammer phenomenon will occur during the process of turning on the cold water. This phenomenon will increase the pressure in the water inlet chamber 111 of the hot water flow channel 110 of the return water valve 10 (increase by about 0.2 - 0.3 MPa). The pressure difference between the water inlet chamber 111 and the water outlet chamber 113 of the hot water flow channel 110 has a tendency to push the linkage valve 300 upwards, thereby squeezing the water flow in the water outlet chamber 113, increasing the water pressure in the water outlet chamber 113. Furthermore, the water pressure in the water outlet chamber 113 pushes open the pressure relief valve 700, causing the pressure relief valve 700 to move to the pressure relief position, making the pressure relief flow channel 150 conductive. A small part of the water flow in the water outlet chamber 113 is discharged to the one-way flow channel 130 through the pressure relief flow channel 150, thereby realizing the pressure relief of the water outlet chamber 113 to ensure that the pressure in the water outlet chamber 113 is not too high and there is a certain pressure difference. In this way, it can be ensured that when the cold water mode is turned on, the linkage valve 300 can be better maintained at the initial position without opening, preventing the problem of cross-water flow after the cold water is turned on. After switching the working mode subsequently, the linkage valve 300 can be easily opened.

[0100] Due to the presence of the pressure relief valve 700, even if water hammer occurs in the cold water of the cold water mode switch, the pressure in the water outlet cavity 113 of the hot water flow channel 110 will not be too high. Therefore, as Figure 6 shown, after the zero cold water mode is turned on, the circulation pump 70 will push the water flow, increasing the pressure in the water inlet cavity 111 of the return water valve 10. The pressure generated by the circulation pump 70 in the water inlet cavity 111 of the return water valve 10 can better offset the pressure difference, and then push the linkage valve 300 upward to enable the linkage valve 300 to be normally opened, realizing water circulation preheating. This can effectively reduce the situation where after the zero cold water mode is turned on, the linkage valve 300 is locked in the initial position due to the relatively high pressure in the water outlet cavity 113 of the hot water flow channel 110 in the return water valve 10, making it difficult for the linkage valve 300 to be normally opened.

[0101] To solve the problem that after the cold water mode of the water supply system is used, the water pressure in the water outlet cavity of the hot water flow channel in the return water valve is relatively high, locking the switching valve (such as a one-way valve or a linkage valve, etc.) in the initial position and making it difficult to switch positions subsequently, the present invention also proposes a communication valve, a pressure valve assembly including the communication valve, and a water supply system including the pressure valve assembly. The communication valve can be used in cooperation with a conventional return water valve. Without changing the original structure of the return water valve, it can solve the problem that after the cold water mode of the water supply system is used, the water pressure in the water outlet cavity of the hot water flow channel in the return water valve is relatively high, locking the switching valve (such as a one-way valve or a linkage valve, etc.) in the initial position and making it difficult to switch positions subsequently.

[0102] Figures 8 to 16 Schematic diagram of an embodiment of the communication valve proposed by the present invention, a pressure valve assembly including the communication valve, and a water supply system including the pressure valve assembly. The Figures 8 to 16 description of the attached reference numerals can be seen in Table 2 above. The communication valve 80 can be assembled with the return water valve 10 into a pressure valve assembly. When the pressure valve assembly is connected to the cold water pipe 50 and the hot water pipe 60 of the water supply system, a return water waterway can be formed in the water supply system, enabling the water supply system to have a zero cold water mode. It can not only solve the problem of hot water flowing into the cold water pipe when the cold water mode of the water supply system is turned on, but also solve the problem that after the cold water mode of the water supply system is used, the water pressure in the water outlet cavity of the hot water flow channel in the return water valve is relatively high, locking the switching valve (such as a one-way valve or a linkage valve, etc.) in the initial position and making it difficult to switch positions subsequently.

[0103] The communication valve 80 can be manufactured and produced separately and assembled with the return water valve 10 into a pressure valve assembly for use, without the user needing to replace or discard the existing return water valve 10. Of course, the communication valve 80 can also be sold as a set with the return water valve 10 assembled into a pressure valve assembly. The return water valve 10 can be an H-shaped return water valve (such as Figure 8 and Figure 9 shown), or it can be a return water valve of other shapes (such as Figure 15 andFigure 16 as shown below. The connecting valve 80 will be introduced in detail below.

[0104] Please refer to Figure 10 and Figure 11 In an embodiment of the return water valve of the present invention, the connecting valve 80 includes a valve body 600 and a linkage valve 300. The valve body 600 is provided with a hot water channel 610, a pressure relief channel 620 and a docking channel 630. The hot water channel 610 includes a water inlet chamber 611, a water outlet chamber 613 and a communication chamber 612 located between the water inlet chamber 611 and the water outlet chamber 613 for installing the on-off valve 300; the docking channel 630 communicates with the communication chamber 612 for communicating with the inlet end of the one-way channel 130 of the return water valve 10; the pressure relief channel 620 communicates the water outlet chamber 613 with the docking channel 630. A pressure relief valve 700 is provided in the pressure relief channel 620, and the pressure relief valve 700 is adapted to switch between a pressure relief position where the pressure relief channel 620 is conducted and a closed position where the pressure relief channel 620 is closed.

[0105] Specifically, the on-off valve 300 of the connecting valve 80 is arranged in the hot water channel 610, and the on-off valve 300 can be a valve structure with a switching function such as a linkage valve or a one-way valve. Specifically, in this embodiment, the on-off valve 300 is a linkage valve 300. The linkage valve 300 is arranged in the hot water channel 610, and the linkage valve 300 is adapted to switch between an initial position where the water inlet 612a and the water outlet 612b are closed and an open position where the water inlet 612a and the water outlet 612b are opened.

[0106] The linkage valve 300 is installed in the hot water channel 610 of the connecting valve 80. The linkage valve 300 is adapted to move from the initial position to the open position when the difference in water pressure between the water inlet chamber 611 and the water outlet chamber 613 in the hot water channel 610 increases, which has the following two meanings: 1) When the difference in water pressure between the water inlet chamber 611 and the water outlet chamber 613 starts to increase, the linkage valve 300 moves from the initial position to the open position; 2) When the difference in water pressure between the water inlet chamber 611 and the water outlet chamber 613 increases to a preset value, the linkage valve 300 moves from the initial position to the open position. In a specific embodiment, the above two design methods can be selected according to actual needs.

[0107] The hot water passage 610 of the connecting valve 80 is also provided with a water inlet interface 601 at the inlet of its water inlet cavity 611, and a water outlet interface 602 is provided at the outlet of the water outlet cavity 613. To facilitate the introduction of the way of assembling the connecting valve 80 and the return water valve 10 into a pressure valve assembly, the basic structure of the return water valve 10 will be described first here. The return water valve 10 includes a valve body 100, and the valve body 100 has a hot water flow passage 110, a cold water flow passage 120 and a one-way flow passage 130 that connects the hot water flow passage 110 and the cold water flow passage 120. Among them, the hot water flow passage 110 has a first interface 101 and a second interface 102; the cold water flow passage 120 has a third interface 103 and a fourth interface 104. When the connecting valve 80 and the return water valve 10 are assembled, one of the first interface 101 and the second interface 102 of the return water valve 10 is connected to the docking flow passage 630 of the connecting valve 80, and the other is set to be blocked, so that the connecting valve 80 and the return water valve 10 can be assembled into a pressure valve assembly. Among them, the docking flow passage 630 of the connecting valve 80 is integrally connected with the first interface 101 and the second interface 102 of the return water valve 10, or the docking flow passage 630 of the connecting valve 80 is detachably connected to the first interface 101 and the second interface 102 of the return water valve 10. Specifically here, the docking flow passage 630 of the connecting valve 80 is detachably connected to the first interface 101 of the return water valve 10; for example, a thread is provided at the outlet of the docking flow passage 630 of the connecting valve 80, so that the docking flow passage 630 is threadedly connected to the first interface 101 of the return water valve 10.

[0108] When assembling the pressure valve assembly into the water supply system, the water inlet interface 601 of the connecting valve 80 is connected to the water outlet pipe 22 of the hot water supply device 20 through a hot water pipe 50, and the water outlet interface 602 of the connecting valve 80 is connected to the hot water access end 31 of the mixing device 30; the third interface 103 of the cold water hot valve 10 is connected to a cold water source (such as a tap water pipeline) through a cold water pipe 60, and the fourth interface 104 is connected to the cold water access end 32 of the mixing device 30. In addition, the water supply system is also equipped with a circulating water pump 70, and the circulating water pump 70 is used to connect the third interface 103 and the water inlet pipe 21 of the hot water supply device 20 for sucking cold water. Specifically, the circulating water pump 70 is arranged on the water inlet pipe 21 of the hot water supply device 20.

[0109] Since the water supply system is equipped with a pressure valve assembly, the water supply system has at least three working modes: a cold water mode, a hot water mode and a zero cold water mode. The working principles of these three working modes will be explained below. For details, please refer to the following text.

[0110] Please refer to Figure 8 and Figure 9, when the water supply system uses the cold water mode, the linkage valve 300 is in the initial position; at this time, the pressure of the cold water flow channel 120 of the return water valve 10 decreases, and the water flow in the cold water pipe 60 flows from the cold water flow channel 120 to the cold water access end 32 of the mixing device 30, and then is supplied to the water outlet device 40 through the output end of the mixing device 30. At this time, the check valve core 210 of the check valve 200 is in the closed position under the tension of the return spring 220.

[0111] In the above cold water mode, due to the decrease in the pressure of the cold water pipe 60, the pressure of the cold water flow channel 120 of the return water valve 10 will decrease. The water inlet cavity 611 of the hot water channel 610 of the communication valve 80 is connected to the hot water pipe 50, and the pressure of the hot water pipe 50 is higher than that of the cold water pipe 60. The water flow in the hot water pipe 50 has a tendency to flow from the water inlet cavity 611 through the butt joint flow channel 630 to the cold water flow channel 120, thus having a tendency to push the linkage valve 300 towards the water outlet cavity 613; in addition, the water outlet cavity 613 of the hot water channel 610 is connected to the hot water access end 31 of the mixing device 30, and the hot water access end 31 is in a closed state in this mode, so the water outlet cavity 613 is in a pressure maintaining state. The pressure reduction of the cold water flow channel 120 also causes a pressure difference between the water outlet cavity 613 of the hot water channel 610 and the cold water flow channel 120. Therefore, the water pressure of the water outlet cavity 613 also has a tendency to push and press the linkage valve 300 towards the water inlet cavity 611, thus offsetting the thrust of the water inlet cavity 611 of the hot water channel 610 on the linkage valve 300 and restricting the movement and opening of the linkage valve 300, so that the linkage valve 300 remains in the initial position.

[0112] Please refer to Figure 8 and Figure 13 , when the water supply system uses the hot water mode, the pressure of the water outlet cavity 613 of the hot water channel 610 in the communication valve 80 decreases and drops below the pressure of the water inlet cavity 611, making the pressure difference between the water inlet cavity 611 and the water outlet cavity 613 increase. The water flow in the water inlet cavity 611 pushes open the linkage valve 300, causing the linkage valve 300 to move to the open position. Thus, the water flow in the hot water pipe 50 flows from the hot water channel 610 through the water inlet cavity 611 to the water outlet cavity 613, and then enters the mixing device 30 from the hot water access end 31 of the mixing device 30 and is supplied to the water outlet device 40 through the outlet of the mixing device 30. The flow rate of the hot water pipe 50 increases, and the hot water supply device 20 starts to prepare hot water. At this time, the check valve core 210 of the check valve 200 is in the closed position under the tension of the return spring 220.

[0113] Please refer to Figure 8 and Figure 14, when the zero - cold - water mode is used in the water supply system, the circulation pump 70 is turned on and pushes the water flow to make the water pressure in the hot - water pipe 50 increase. As a result, the pressure in the water inlet chamber 611 of the hot - water channel 610 in the connection valve 80 increases, which then pushes the linkage valve 300 upward. When at rest, the pressure in the water inlet chamber 611 and the water outlet chamber 613 of the connection valve 80 is equal. At this time, the linkage valve 300 reaches the open position, and the linkage valve 300 opens the water inlet 612a of the communication chamber 612. The water flow in the hot - water pipe 50 enters the docking flow channel 630 from the water inlet chamber 612a of the hot - water channel 610, and then flows from the docking flow channel 630 to the hot - water flow channel 110 of the return valve 10. After these water flows enter the one - way flow channel 130, they overcome the acting force of the return spring 220 and push open the one - way valve 200. The water flows through the one - way flow channel 130 into the cold - water flow channel 120, and then returns to the hot - water supply device 20 through the cold - water pipe 60 for circulating heating.

[0114] As introduced above, when using the cold - water mode, a water hammer phenomenon will occur during the process of switching on the cold water. This phenomenon will cause the pressure in the water inlet chamber 611 of the hot - water channel 610 in the connection valve 80 to increase (increase by about 0.2 - 0.3 MPa). The pressure difference between the water inlet chamber 611 and the water outlet chamber 613 of the hot - water channel 610 has a tendency to push the linkage valve 300 upward, thereby squeezing the water flow in the water outlet chamber 613, increasing the water pressure in the water outlet chamber 613. Then, the water pressure in the water outlet chamber 613 pushes open the pressure - relief valve 700, causing the pressure - relief valve 700 to move to the pressure - relief position, making the pressure - relief flow channel 620 conduct. A small part of the water flow in the water outlet chamber 613 is discharged to the docking flow channel 630 through the pressure - relief flow channel 620, thereby realizing the pressure relief of the water outlet chamber 613 to ensure that the pressure in the water outlet chamber 613 is not too high and there is a certain pressure difference. In this way, it can be ensured that when the cold - water mode is turned on, the linkage valve 300 can be better maintained at the initial position without opening, preventing the problem of water mixing after the cold - water operation is turned on. After the subsequent working mode is switched, the linkage valve 300 can be easily opened.

[0115] Due to the existence of the pressure - relief valve 700, even if a water hammer phenomenon occurs during the switching on and off of the cold water in the cold - water mode, the pressure in the water outlet chamber 613 of the hot - water channel 610 in the connection valve 80 will not be too high. Therefore, as Figure 6 shown, after the zero - cold - water mode is turned on, the circulation pump 70 will push the water flow to make the pressure in the water inlet chamber 611 of the hot - water channel 610 increase. The pressure generated by the circulation pump 70 on the water inlet chamber 611 of the connection valve 80 can better offset the pressure difference, and then push the linkage valve 300 upward so that the linkage valve 300 can be normally opened to realize the water - cycle pre - heating. This can effectively reduce the situation that after the zero - cold - water mode is turned on, due to the relatively high pressure in the water outlet chamber 613 of the hot - water channel 610 in the connection valve 80, the linkage valve 300 is locked at the initial position, making it difficult for the linkage valve 300 to be normally opened.

[0116] In the technical solution of the present invention, a hot water channel 610, a pressure relief channel 620 and a docking channel 630 are arranged in the communication valve 80; wherein, the hot water channel 610 has a water inlet cavity 611, a water outlet cavity 613 and a communication cavity 612 located between the water inlet cavity 611 and the water outlet cavity 613 for installing the on-off valve 300; the pressure relief channel 620 communicates the water outlet cavity 613 and the docking channel 630, and the docking channel 630 communicates with the communication cavity 612, and the docking channel 630 is used to connect with the hot water channel 110 of the return water valve 10; and, a pressure relief valve 700 is arranged in the pressure relief channel 620, and the pressure relief valve 700 is adapted to switch between a pressure relief position for conducting the pressure relief channel 620 and a closed position for closing the pressure relief channel 620. When the water pressure in the water outlet cavity 613 of the hot water channel 110 is relatively high, the water outlet cavity 613 is pressure-relieved through the pressure relief valve 700 to ensure that the pressure of the water outlet cavity 613 is not too high, so as to ensure that the linkage valve 300 can be locked in the cold water mode and can be better opened when switched to the zero cold water mode (please refer to the foregoing description for details).

[0117] It can be seen that the water supply system can, on the original basis, only combine the communication valve 80 with the existing return water valve 10 to solve the problem that the hot water supply device 20 is accidentally started due to the water volume cross-flow in the hot water pipe 50, so that the hot water supply device 20 does not start when cold water is turned on, without the need to replace or discard the existing return water valve 10, nor to change the original basic structure of the return water valve 10.

[0118] Please refer to Figure 10 and Figure 11 In an embodiment, the pressure relief channel 620 is provided with a pressure relief port 621 communicating with the water outlet cavity 613; the pressure relief valve 700 includes a pressure relief valve core 710 and a pressure relief reset member 720. Among them, the pressure relief valve core 710 is arranged opposite to the pressure relief port 621 for opening and closing the pressure relief port 621; the pressure relief reset member 720 is fixed in the valve body 600 and is connected to the pressure relief valve core 710.

[0119] Specifically, the pressure relief reset member 720 has elasticity. When the pressure relief valve 700 is in the closed position, the tension of the pressure relief reset member 720 limits the pressure relief valve core 710 at the position of closing the pressure relief port 621; when the water pressure in the water outlet cavity 613 is greater than the tension of the pressure relief reset member 720, the water flow in the water outlet cavity 613 will push open the pressure relief valve core 710, so that the pressure relief port 621 is opened. At this time, the pressure relief reset member 720 is squeezed and stores elastic potential energy, and this elastic potential energy is used to drive the pressure relief valve core 710 to return to the closed position after the pressure relief is completed.

[0120] As for the specific structural type of the pressure relief reset member 720, there can be multiple structural types. For example, but not limited to, the pressure relief reset member 720 can be a spring, a spring piece, a tension spring or other elastic structures. Specifically, in this embodiment, the pressure relief reset member 720 is configured as a pressure relief spring 720. One end of the pressure relief spring 720 is fixed inside the valve body 600, and the other end of the pressure relief spring 720 is connected to the pressure relief valve core 710.

[0121] Please refer to Figure 10 and Figure 11 , in one embodiment, in order to ensure that the pressure relief valve core 710 accurately moves to switch the pressure relief port 621, a limiting groove 622 corresponding to and communicating with the pressure relief port 621 is provided on the side wall of the pressure relief flow channel 620; the pressure relief valve core 710 is axially movably installed in the limiting groove 622. Since the pressure relief valve core 710 is limited to move within the limiting groove 622, the pressure relief valve core 710 is always aligned with the pressure relief port 621, so that the pressure relief valve core 710 accurately switches the pressure relief port 621 during the movement process, avoiding the situation that the pressure relief valve core 710 is misaligned with the pressure relief port 621.

[0122] Please also refer to Figure 10 and Figure 11 , considering that the water pressure in the water circuits of different user families is different, and thus the degree of pressure relief required for the water outlet cavity is also different. Therefore, in order to make the communication valve 80 applicable to the water pressure of different user families, optionally, the communication valve 80 further includes a pressure regulating member 640 installed on the valve body 600 for the pressure relief spring 720 to be connected and fixed. The pressure regulating member 640 is movable relative to the valve body 600 to adjust the distance between the pressure regulating member 640 and the pressure relief valve core 710.

[0123] Specifically, since the two ends of the pressure relief reset member 720 are respectively connected between the pressure relief valve core 710 and the pressure regulating member 640, therefore, adjusting the distance between the pressure regulating member 640 and the pressure relief valve core 710 can also adjust the tightness of the pressure relief spring 720 squeezed by the pressure regulating member 640 and the pressure relief valve core 710, so that the pressure relief spring 720 has different pressure relief elastic forces, and further makes the pressure relief valve 700 have different pressure relief values. For example, reducing the distance between the pressure regulating member 640 and the pressure relief valve core 710 makes the pressure relief spring 720 compressed to a greater extent, so that the pressure relief spring 720 has a greater pressure relief elastic force. At this time, the water outlet cavity 613 needs to have a higher water pressure to overcome the pressure relief elastic force of the pressure relief spring 720 to push the pressure relief valve core 710 to the pressure relief position; vice versa. Therefore, when the water pressure in the user's family water circuit is relatively high, the distance between the pressure regulating member 640 and the pressure relief valve core 710 can be appropriately reduced. Conversely, the distance between the pressure regulating member 640 and the pressure relief valve core 710 can be appropriately increased.

[0124] Further, the valve body 600 is provided with an installation port 623 for installing the pressure regulating member 640; the pressure regulating member 640 is in threaded fit with the installation port 623. During adjustment, by rotating the pressure regulating member 640, the pressure regulating member 640 can be relatively close to or far away from the pressure relief valve core 710, so as to adjust the distance between the two.

[0125] Please refer to Figure 10 and Figure 12 , based on any one of the above embodiments, for the structure of the linkage valve 300, the communication cavity 612 has a water inlet 612a communicating with the water inlet cavity 611 and a water outlet 612b communicating with the water outlet cavity 613; the switching valve 300 of the communication valve 80 is the linkage valve 300, and the linkage valve 300 is adapted to switch between an initial position and an open position, wherein: in the initial position, one end of the linkage valve 300 blocks the water outlet 612b of the communication cavity 612, and a gap 301 is formed between the other end of the linkage valve 300 and the water inlet 612a of the communication cavity 612; in the open position, the linkage valve 300 opens both the water inlet 612a and the water outlet 612b of the communication cavity 612.

[0126] Specifically, the linkage valve 300 covers but does not completely block the water inlet 612a of the communication cavity 612 in the initial position, so as to form a narrow gap 301 between the linkage valve 300 and the water inlet 612a (it should be noted that this gap is not enough to keep the water inlet 612a in an open state). When a water hammer phenomenon occurs in the cold water mode, a small part of the water flow in the water inlet cavity 611 of the hot water channel 610 in the valve body 600 will enter the communication cavity 612 from the gap 301, so as to relieve the pressure of the water inlet cavity 611, reduce the situation that the pressure of the water inlet cavity 611 is greater than that of the water outlet cavity 613, make the upward force exerted on the linkage valve 300 by the water flow in the water inlet cavity 611 and the downward force exerted on the linkage valve 300 by the water flow in the water outlet cavity 613 basically the same, so as to prevent the water flow in the water inlet cavity 611 from pushing the linkage valve 300 upward, keep the linkage valve 300 in the initial position, and further greatly reduce the amount of water leaking from the hot water pipe 50 into the communication cavity 612.

[0127] This part of the smaller amount of water is not enough to push open the check valve 200, so that the water flow in the hot water pipe 50 will not flow into the cold water flow channel 120 in large quantities through the one-way flow channel 130. This part of the water volume is much smaller than the flow rate at which the hot water supply device 20 starts, thus solving the problem that the water flow in the hot water pipe 50 flows into the cold water flow channel 120 due to the water hammer phenomenon in the cold water mode, effectively reducing the situation that the hot water supply device 20 is accidentally started due to the increase in the flow rate of the hot water pipe 50, and realizing that the hot water supply device 20 does not start when the cold water is turned on. That is to say, the pressure of the water inlet cavity 611 can be relieved through the gap 301; the pressure of the water outlet cavity 113 can be relieved through the pressure relief valve 700.

[0128] Please refer toFigure 10 and Figure 12 In one embodiment, the linkage valve 300 includes a valve core seat 310 disposed in the water outlet cavity 613 for blocking the water outlet 612b of the communication cavity 612, and a valve core 320 disposed in the communication cavity 612 and linked with the valve core seat 310; in the initial position, the linkage valve 300 forms the gap 301 between the valve core 320 and the water inlet 612a of the communication cavity 612.

[0129] Specifically, the valve core seat 310 and the valve core 320 of the linkage valve 300 are linked in the same direction. In the initial position, the linkage valve 300 blocks the water outlet 612b of the communication cavity 612 through the valve core seat 310, and a gap 301 is formed between the valve core 320 of the linkage valve 300 and the water inlet 612a of the communication cavity 612. When the linkage valve 300 moves upward to the open position under the action of the water pressure difference on both sides, the valve core seat 310 of the linkage valve 300 opens the water outlet 612b of the communication cavity 612, and the valve core 320 of the linkage valve 300 opens the water inlet 612a of the communication cavity 612. Vice versa.

[0130] As for the way of the linkage setting of the valve core seat 310 and the valve core 320 of the linkage valve 300, there can be various design schemes. For example, in one embodiment, the valve core seat 310 is provided with a connecting shaft 311 extending toward the water outlet 612b of the communication cavity 612; the valve core 320 is sleeved on the connecting shaft 311. Here, it is considered that there may be structural design or assembly errors in the design process of the communication valve 80, so that after the linkage valve 300 is installed in the hot water flow channel 110 of the communication valve 80, there may be a problem of zero gap or excessive gap between the valve core 320 of the linkage valve 300 and the water inlet 612a of the communication cavity 612 of the hot water flow channel 110. To reduce the occurrence of this situation, optionally, the length of the valve core 320 sleeved on the connecting shaft 311 is set to be adjustable, so that the size of the gap 301 formed between the valve core 320 and the water inlet 612a of the communication cavity 612 is adjustable.

[0131] Specifically, please refer to Figure 12 , Figure 12 where h1 represents the length of the valve core 320 sleeved on the connecting shaft 311; h2 represents the size of the gap 301 between the valve core 320 and the water inlet 612a of the communication cavity 612. The size of the gap 301 refers to the width size in the axial direction of the connecting shaft 311. By adjusting the length of the upper end portion of the valve core 320 sleeved on the connecting shaft 311, the distance between the lower end portion of the valve core 320 and the water inlet 612a of the communication cavity 612 can be adjusted, so as to adjust the size of the gap 301 formed between the valve core 320 and the water inlet 612a of the communication cavity 612.

[0132] For example, by reducing the length of the valve core 320 sleeved on the connecting shaft 311, the lower end of the valve core 320 will approach the water inlet 612a of the communication cavity 612, thereby reducing the distance between the lower end of the valve core 320 and the water inlet 612a of the communication cavity 612, and reducing the gap 301 between the valve core 320 and the water inlet 612a of the communication cavity 612 (that is, when h1 decreases, h2 also decreases).

[0133] Please refer to Figure 10 and Figure 12 As for the method of realizing the adjustable length of the valve core 320 sleeved on the connecting shaft 311, there can be various design methods. In one embodiment, one end of the valve core 320 is provided with a socket hole 322 sleeved on the connecting shaft 311, and the other end is provided with an adjusting screw hole 323 communicating with the socket hole 322; the valve core 320 further includes an adjusting screw 330, and the adjusting screw 330 is installed in the adjusting screw hole 323 and is in contact and cooperation with the end face of the connecting shaft 311.

[0134] When it is necessary to adjust the size of the gap 301, rotate the adjusting screw 330. Since the inner end face of the adjusting screw 330 is in contact with and abuts against the end face of the connecting shaft 311, the relative position of the adjusting screw 330 and the connecting shaft 311 remains unchanged, while the valve core 320 threadedly engaged with the adjusting screw 330 expands and contracts along its axial direction relative to the connecting shaft 311, thereby changing the length of the valve core 320 sleeved on the connecting shaft 311 and realizing the adjustable length of the valve core 320 sleeved on the connecting shaft 311.

[0135] Of course, in another embodiment, internal threads can also be directly provided on the inner peripheral surface of the socket hole 322 of the valve core 320, and external threads can be provided on the outer peripheral surface of the connecting shaft 311, so that the internal threads of the valve core 320 are engaged with the external threads of the connecting shaft 311, and by directly rotating the valve core 320, the length of the valve core 320 sleeved on the lower shaft section 332 can be changed, and further the adjustable length of the valve core 320 sleeved on the connecting shaft 311 can be realized.

[0136] Please refer to Figure 10 and Figure 12 As for the position of the gap 301 formed between the valve core 320 and the water inlet 612a of the communication cavity 612, optionally, an annular sealing portion 321 is convexly provided on the outer peripheral wall of one end of the valve core 320 away from the valve core seat 310. At the initial position, a gap 301 is formed between the annular sealing portion 321 and the water inlet 612a of the communication cavity 612. It can be understood that the valve core 320 covers but does not completely block the water inlet 612a of the communication cavity 612 through the annular sealing portion 321, so as to form a narrow gap 301 between the annular sealing portion 321 and the water inlet 612a.

[0137] Please refer to Figure 10, based on any of the above embodiments, the connection valve 80 further includes a reset member 400, and the reset member 400 is used to make the linkage valve 300 have a tendency to reset to the initial position. Thus, after the hot water usage of the water outlet device 40 ends or after the preheating of the hot water in the hot water pipe 50 ends, etc., the reset member 400 can drive the linkage valve 300 to reset to the initial position. The reset member 400 can also be a spring, a spring piece, a tension spring, or other elastic structures

[0138] Optionally, the reset member 400 is configured as a reset spring 400. One end of the reset spring 400 is fixed in the water outlet cavity 613, and the other end of the reset spring 400 is connected to the linkage valve 300. The reset spring 400 is used to make the core of the linkage valve 300 have a tendency to reset to the initial position. Thus, on the one hand, after the hot water usage of the water outlet device 40 ends or after the preheating of the hot water in the hot water pipe 50 ends, etc., the reset spring 400 can drive the linkage valve 300 to reset to the initial position; on the other hand, the reset spring 400 can also limit the linkage valve 300 to the initial position to ensure the use stability of the linkage valve 300 at the initial position.

[0139] Please refer to Figure 10 , in one embodiment, the linkage valve 300 further includes a gasket 340, and the gasket 340 is arranged on the lower surface of the valve core seat 310. Specifically, the lower surface of the valve core seat 310 is convexly provided with a mounting portion 312 surrounding the outer circumference of the connecting shaft 311; the gasket 340 is sleeved on the mounting portion 312. The gasket 340 can be made of a material such as rubber that has elasticity and a better sealing effect, so as to seal the gap between the valve core seat 310 and the water outlet 112b of the communication cavity 112 when the linkage valve 300 is in the initial position, and improve the sealing effect of closing the water outlet 112b.

[0140] Please refer to Figure 1 , the present invention also provides a pressure valve assembly, and the pressure valve assembly includes a return water valve 10 and a connection valve 80. The specific structure of the connection valve 80 refers to the above embodiments. Since this pressure valve assembly adopts all the technical solutions of the above embodiments, it also has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here one by one. The connection valve 80 of the pressure valve assembly can be manufactured and produced separately and assembled with the return water valve 10 to form a pressure valve assembly for use, without the user having to replace or discard the existing return water valve 10, nor having to change the original basic structure of the return water valve 10. Of course, the connection valve 80 can also be assembled with the return water valve 10 to form a pressure valve assembly and sold in a set.

[0141] Optionally, the return water valve 10 can be an H-shaped return water valve (such as Figure 8 and Figure 9 shown), or it can be a return water valve of other shapes (such as Figure 15 and Figure 16As shown in the figure. The return water valve 10 has a hot water flow channel 110, a cold water flow channel 120, and a one-way flow channel 130 that connects the hot water flow channel 110 and the cold water flow channel 120; among them, the hot water flow channel 110 has a first interface 101 and a second interface 102, and one of the first interface 101 and the second interface 102 is set to be blocked, and the other is connected to the docking flow channel 630 of the connection valve 80, so that the docking flow channel 630 of the connection valve 80 is connected to the inlet end of its one-way flow channel 130 through the hot water flow channel 110 of the return water valve 10.

[0142] Specifically herein, a docking interface 631 is provided at the end of the docking flow channel 630; the first interface 101 of the hot water flow channel 110 is connected to the docking interface 603 of the docking flow channel 630 of the connection valve 80, and the second interface 102 of the hot water flow channel 110 is set to be blocked. The connection method between the first interface 101 of the hot water flow channel 110 and the docking interface 603 of the connection valve 80 can be but is not limited to: threads are provided at both the docking interface 603 and the first interface 101 of the return water valve 10, so that the docking interface 603 is threadedly connected to the first interface 101. In other embodiments, the second interface 102 of the hot water flow channel 110 can also be connected to the docking flow channel 630 of the connection valve 80, and the first interface 101 of the hot water flow channel 110 is set to be blocked.

[0143] As for the blocking method of blocking the first interface 101 or the second interface 102 of the return water valve 10, there can be various design methods. For example, in one embodiment, the pressure valve assembly further includes a sealing cover 140, and the sealing cover 140 is suitable for covering one of the first interface 101 and the second interface 102 of the return water valve 10, so that the other is connected to the docking interface 603 of the connection valve 80.

[0144] Specifically, the sealing cover 140 covers the second interface 102 of the return water valve 10, and the first interface 101 of the return water valve 10 is connected to the docking interface 603 of the connection valve 80. In addition, in other embodiments, a plug can also be configured for the pressure valve assembly, and the second interface 102 of the return water valve 10 can be blocked by using the plug, so that the second interface 102 can also be blocked. Thus, it can be seen that only one of the first interface 101 and the second interface 102 of the return water valve 10 needs to be blocked, and the other is connected to the docking interface 603 of the connection valve 80, and the connection valve 80 can be combined with the return water valve 10 to form a pressure valve assembly applied to the water supply system, thereby solving the problem that the hot water supply device 20 is accidentally started due to the cross-flow of the water volume in the hot water pipe 50, realizing that the hot water supply device 20 does not start when cold water is turned on, without the need to replace or discard the existing return water valve 10, and without the need to change the basic structure of the return water valve 10 in the water supply system.

[0145] Please refer to Figure 10, based on any of the above embodiments, the return water valve 10 further includes a water regulating valve 500. The water regulating valve 500 is installed in the cold water flow channel 120 through the installation port to regulate the water flow rate in the cold water flow channel 120. Optionally, the hot water flow channel 110 is a straight flow channel, and / or the cold water flow channel 120 is a straight flow channel, and / or the one-way flow channel 130 is a straight flow channel. Or, in other embodiments, any one or more of the hot water flow channel 110, the cold water flow channel 120, and the one-way flow channel 130 may also be provided as an L-shaped flow channel.

[0146] Please refer to Figure 8 or Figure 15 , the present invention also provides a water supply system, which includes a hot water supply device 20, a water mixing device 30 and a pressure valve assembly. Among them, the hot water supply device 20 has a water inlet pipe 21 and a water outlet pipe 22; the hot water access end 31 of the water mixing device 30 is connected to the water outlet pipe 22 through a hot water pipe 50, and the cold water access end 32 of the water mixing device 30 is connected to the water inlet pipe 21 through a cold water pipe 60; the hot water channel 610 of the connection valve 80 in the pressure valve assembly is connected to the hot water pipe 50, and the cold water flow channel 120 of the return water valve 10 in the pressure valve assembly is connected to the cold water pipe 60. The specific structure of the pressure valve assembly refers to the above embodiments. Since this water supply system adopts all the technical solutions of the above all embodiments, it also has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated here one by one.

[0147] For the pressure valve assembly, the connection valve 80 of the pressure valve assembly can be manufactured and produced separately and assembled with the return water valve 10 to form a pressure valve assembly for use, without the user having to replace or discard the existing return water valve 10. Of course, the connection valve 80 can also be assembled with the return water valve 10 into a pressure valve assembly and sold as a set. The return water valve 10 can be an H-type return water valve (such as Figure 8 and Figure 9 shown), or it can also be a return water valve of other shapes (such as Figure 15 and Figure 16 shown).

[0148] Optionally, the water supply system further includes a water outlet device 40, and the water outlet device 40 is connected to the output end 33 of the water mixing device 30. The number of water outlet devices 40 can be one or two or more. When there are two or more water outlet devices 40, a connection valve 80 can be configured for each water outlet device 40, or a connection valve 80 can be configured only for the water outlet device 40 arranged at the farthest end. Of course, in other embodiments, the water outlet device 40 can also be provided by the user himself.

[0149] As for the specific type of the hot water supply device 20, the hot water supply device 20 can be selected as a gas water heater or a gas wall-mounted boiler or an electric water heater, and can be reasonably configured according to market or user needs, and no specific limitation is set here.

[0150] Since the water supply system is configured with a pressure valve assembly, the water supply system has at least three working modes: cold water mode, hot water mode, and zero cold water mode. The working principles of these three working modes will be explained below. For details, please refer to the following text.

[0151] Please refer to Figure 8 and Figure 9 , when the water supply system uses the cold water mode, the linkage valve 300 is in the initial position; at this time, the pressure of the cold water flow channel 120 of the return water valve 10 decreases, and the water flow in the cold water pipe 60 flows from the cold water flow channel 120 to the cold water access end 32 of the mixing device 30, and then is supplied to the water outlet device 40 through the output end of the mixing device 30. At this time, the one-way valve core 210 of the one-way valve 200 is in the closed position under the tension of the return spring 220.

[0152] In the above cold water mode, since the pressure of the cold water pipe 60 decreases, the pressure of the cold water flow channel 120 of the return water valve 10 will decrease. The water flow in the hot water pipe 50 has a tendency to flow from the water inlet cavity 611 to the cold water flow channel 120 through the butt flow channel 630, and thus has a tendency to push the linkage valve 300 towards the water outlet cavity 613; in addition, the water outlet cavity 613 connected to the hot water access end 31 of the mixing device 30 is in a closed state in this mode, so the water outlet cavity 613 is in a pressure maintaining state. The pressure reduction of the cold water flow channel 120 also causes a pressure difference between the water outlet cavity 613 of the hot water channel 610 and the cold water flow channel 120. Therefore, the water pressure in the water outlet cavity 613 also has a tendency to push and press the linkage valve 300 towards the water inlet cavity 611, thereby offsetting the thrust of the water inlet cavity 611 of the hot water channel 610 on the linkage valve 300 and restricting the movement and opening of the linkage valve 300, so that the linkage valve 300 remains in the initial position.

[0153] Please refer to Figure 8 and Figure 13 , when the water supply system uses the hot water mode, the pressure of the water outlet cavity 613 of the hot water channel 610 in the connection valve 80 decreases and drops below the pressure of the water inlet cavity 611, increasing the pressure difference between the pressure in the water inlet cavity 611 and the pressure in the water outlet cavity 613. The water flow in the water inlet cavity 611 pushes open the linkage valve 300, causing the linkage valve 300 to move to the open position. Thus, the water flow in the hot water pipe 50 flows from the hot water channel 610 through the water inlet cavity 611 to the water outlet cavity 613, and then enters the mixing device 30 from the hot water access end 31 of the mixing device 30 and is supplied to the water outlet device 40 through the outlet of the mixing device 30. The flow rate of the hot water pipe 50 increases, and the hot water supply device 20 starts to prepare hot water. At this time, the one-way valve core 210 of the one-way valve 200 is in the closed position under the tension of the return spring 220.

[0154] Please refer to Figure 8 and Figure 14 When the zero - cold - water mode is used in the water supply system, the circulation pump 70 is turned on and pushes the water flow, causing the water pressure in the hot - water pipe 50 to increase. The pressure in the water inlet chamber 611 of the hot - water channel 610 in the connection valve 80 increases, thus pushing the linkage valve 300 upward. When it is stationary, the pressures in the water inlet chamber 611 and the water outlet chamber 613 of the connection valve 80 are equal. At this time, the linkage valve 300 reaches the open position, and the linkage valve 300 opens the water inlet 612a of the communication chamber 612. The water flow in the hot - water pipe 50 enters the docking flow channel 630 from the water inlet chamber 612a of the hot - water channel 610, and then flows from the docking flow channel 630 to the hot - water flow channel 110 of the return - water valve 10. After these water flows enter the one - way flow channel 130, they overcome the acting force of the return spring 220 and push open the one - way valve 200. The water flows through the one - way flow channel 130 into the cold - water flow channel 120, and then returns to the hot - water supply device 20 through the cold - water pipe 60 for circulating heating.

[0155] As described above, when using the cold - water mode, a water - hammer phenomenon will occur during the switching of cold water. This phenomenon will cause the pressure in the water inlet chamber 611 of the hot - water channel 610 in the connection valve 80 to increase (increase by about 0.2 - 0.3 MPa). The pressure difference between the water inlet chamber 611 and the water outlet chamber 613 of the hot - water channel 610 has a tendency to push the linkage valve 300 upward, thus squeezing the water flow in the water outlet chamber 613, causing the water pressure in the water outlet chamber 613 to increase. Furthermore, the water pressure in the water outlet chamber 613 pushes open the pressure - relief valve 700, causing the pressure - relief valve 700 to move to the pressure - relief position, making the pressure - relief flow channel 620 conduct. A small part of the water flow in the water outlet chamber 613 is discharged to the docking flow channel 630 through the pressure - relief flow channel 620, thereby realizing the pressure - relief of the water outlet chamber 613 to ensure that the pressure in the water outlet chamber 613 is not too large and there is a certain pressure difference. In this way, it can be ensured that when the cold - water mode is turned on, the linkage valve 300 can be better maintained in the initial position without opening, preventing the problem of water mixing after the cold - water opening action. After switching the working mode later, the linkage valve 300 can be easily opened.

[0156] Due to the existence of the pressure - relief valve 700, even if a water - hammer phenomenon occurs during the switching of cold water in the cold - water mode, the pressure in the water outlet chamber 613 of the hot - water channel 610 in the connection valve 80 will not be too large. Therefore, as Figure 6As shown, after the zero cold water mode is turned on, the circulation water pump 70 will push the water flow, increasing the pressure in the water inlet chamber 611 of the hot water channel 610. The pressure generated by the circulation water pump 70 on the water inlet chamber 611 of the connection valve 80 can better offset the pressure difference, thereby pushing the linkage valve 300 upward to enable the linkage valve 300 to be normally opened, realizing water circulation preheating. This can effectively reduce the situation where, after the zero cold water mode is turned on, the linkage valve 300 is locked in the initial position due to the relatively high pressure in the water outlet chamber 613 of the hot water channel 610 in the connection valve 80, making it difficult for the linkage valve 300 to be normally opened.

[0157] From the above introduction, it can be seen that the water supply system can, on the original basis, solve the problem of accidental startup of the hot water supply device 20 caused by water cross-flow in the hot water pipe 50 by simply combining the connection valve 80 with the existing return water valve 10, realizing that the hot water supply device 20 does not start when cold water is turned on, without the need to replace or discard the existing return water valve 10, nor to change the original basic structure of the return water valve 10.

[0158] The above are only optional embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural transformation made using the content of the specification and drawings of the present invention under the inventive concept of the present invention, or any direct / indirect application in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A water return valve, characterized in that, The return valve comprises: A valve body, wherein the valve body is provided with a hot water flow channel, a cold water flow channel, a one-way flow channel and a pressure relief flow channel; the hot water flow channel includes a water inlet chamber, a water outlet chamber and a connecting chamber located between the water inlet chamber and the water outlet chamber for installing a switch valve; the hot water flow channel is provided with a first interface at the inlet of its water inlet chamber, and a thread is arranged at the first interface, and the hot water flow channel is provided with a second interface at the outlet of its water outlet chamber; the one-way flow channel connects the connecting chamber with the cold water flow channel; the pressure relief flow channel connects the water outlet chamber with the one-way flow channel; and A pressure relief valve is provided in the pressure relief flow channel, and the pressure relief valve is adapted to switch between a pressure relief position for conducting the pressure relief flow channel and a closed position for closing the pressure relief flow channel.

2. The water return valve according to claim 1, characterized in that, The pressure relief flow channel is provided with a pressure relief port communicating with the water outlet cavity; the pressure relief valve comprises: a pressure relief valve core, the pressure relief valve core being arranged opposite to the pressure relief port and being used for opening and closing the pressure relief port; and A pressure relief reset component is fixed in the valve body and connected to the pressure relief valve core.

3. The return water valve according to claim 2, characterized in that The side wall of the pressure relief channel is provided with a limiting groove corresponding to and communicating with the pressure relief port; the pressure relief valve core is movably installed in the limiting groove along its axial direction.

4. The return water valve according to claim 3, characterized in that, The pressure relief reset component is configured as a pressure relief spring; one end of the pressure relief spring is connected to the pressure relief valve core, and the other end of the pressure relief spring is fixed in the valve body.

5. The return water valve according to claim 4, characterized in that, The water return valve further comprises a pressure regulating member installed on the valve body for the pressure relief spring to be connected and fixed, and the pressure regulating member is movable relative to the valve body to adjust the distance between the pressure regulating member and the pressure relief valve core.

6. The return water valve according to any one of claims 1 to 5, characterized in that, The communication chamber has a water inlet connected to the water inlet chamber, and a water outlet connected to the water outlet chamber; the switch valve of the water return valve is a linkage valve, and the linkage valve is suitable for switching between an initial position and an open position, wherein: In the initial position, one end of the linkage valve blocks the water outlet, and a gap is formed between the other end of the linkage valve and the water inlet; In the open position, the linkage valve opens both the water inlet and the water outlet.

7. The return water valve according to claim 6, characterized in that, The linkage valve comprises: a valve core seat, the valve core seat being disposed in the water outlet cavity and used for blocking the water outlet; and A valve core is arranged in the communicating cavity and is linked with the valve core seat. In the initial position, the linked valve forms the gap between the valve core and the water inlet.

8. The return water valve according to claim 7, characterized in that, The valve core seat is provided with a connecting shaft extending toward the water outlet of the communicating cavity; the valve core ring is sleeved on the connecting shaft, and the length of the valve core ring sleeve on the connecting shaft is adjustable.

9. The return water valve according to claim 8, wherein, One end of the valve core is provided with a sleeve hole sleeved with the connecting shaft, and the other end thereof is provided with an adjusting screw hole communicated with the sleeve hole; The linkage valve also includes an adjusting screw, which is installed in the adjusting screw hole and contacts and cooperates with the end surface of the connecting shaft.

10. The return water valve according to claim 7, characterized in that, An annular sealing portion is convexly provided on the outer peripheral wall of one end of the valve core away from the valve core seat, and in the initial position, the gap is formed between the annular sealing portion of the valve core and the water inlet.

11. The return water valve according to claim 7, characterized in that, The linkage valve further comprises a sealing gasket, and the sealing gasket is arranged on the lower surface of the valve core seat.

12. The return water valve according to claim 7, wherein, The return water valve further includes a reset member for making the linkage valve tend to reset to the initial position.

13. The return water valve according to any one of claims 1 to 5, characterized in that, The return water valve further includes a check valve disposed in the one-way flow path for guiding the water flow in the hot water flow path to flow unidirectionally into the cold water flow path during return water.

14. A water supply system, characterized in that, The water supply system includes: A hot water supply device having an outlet pipe and an inlet pipe; A water mixing device, the hot water access end of the water mixing device is connected to the outlet pipe through a hot water pipe, and the cold water access end of the water mixing device is connected to the inlet pipe through a cold water pipe; and The return water valve according to any one of claims 1 to 13, the hot water flow path of the return water valve is connected to the hot water pipe, and the cold water flow path of the return water valve is connected to the cold water pipe.

15. The water supply system according to claim 14, characterized in that, The hot water supply device is a gas water heater or a gas wall-mounted boiler or an electric water heater.

16. A connecting valve, characterized in that, The connection valve includes: A valve body provided with a hot water passage, a pressure relief flow path and a docking flow path, a docking port is provided at the end of the docking flow path, and a thread is provided at the docking port; the hot water passage includes a water inlet cavity, a water outlet cavity and a communication cavity located between the water inlet cavity and the water outlet cavity for installing a switching valve; the docking flow path is communicated with the communication cavity for communicating with the inlet end of the one-way flow path of the return water valve; the pressure relief flow path communicates the water outlet cavity with the docking flow path; and A pressure relief valve disposed in the pressure relief flow path, the pressure relief valve is adapted to switch between a pressure relief position for opening the pressure relief flow path and a closed position for closing the pressure relief flow path.

17. The communication valve according to claim 16, wherein, The pressure relief flow path is provided with a pressure relief port communicated with the water outlet cavity; the pressure relief valve includes: A pressure relief valve core disposed opposite to the pressure relief port for opening and closing the pressure relief port; and A pressure relief reset member fixed in the valve body and connected to the pressure relief valve core.

18. The communicating valve according to claim 17, wherein The side wall of the pressure relief flow path is provided with a limiting groove corresponding to and communicated with the pressure relief port; the pressure relief valve core is axially movably installed in the limiting groove.

19. The communication valve according to claim 18, characterized in that, The pressure relief reset member is configured as a pressure relief spring; one end of the pressure relief spring is connected to the pressure relief valve core, and the other end of the pressure relief spring is fixed on the valve body.

20. The communication valve according to claim 19, wherein, The connection valve further includes a pressure regulating member installed on the valve body for connecting and fixing the pressure relief spring, and the pressure regulating member is movable relative to the valve body to adjust the distance between the pressure regulating member and the pressure relief valve core.

21. The connecting valve according to any one of claims 16 to 20, characterized in that, An end of the docking flow path away from the communication cavity is provided with a docking port for docking with the hot water flow path of the return water valve.

22. The communication valve according to any one of claims 16 to 20, characterized in that, The communication cavity has a water inlet communicating with the water inlet cavity and a water outlet communicating with the water outlet cavity; the switching valve of the connection valve is a linkage valve adapted to switch between an initial position and an open position, wherein: In the initial position, one end of the linkage valve blocks the water outlet, and a gap is formed between the other end of the linkage valve and the water inlet; In the open position, the linkage valve opens both the water inlet and the water outlet.

23. The communicating valve according to claim 22, wherein The linkage valve includes: A valve core seat disposed in the water outlet cavity for blocking the water outlet; and A valve core is arranged in the communicating cavity and is linked with the valve core seat. In the initial position, the linked valve forms the gap between the valve core and the water inlet.

24. The connecting valve according to claim 23, wherein The valve core seat is provided with a connecting shaft extending toward the water outlet of the communicating cavity; the valve core ring is sleeved on the connecting shaft, and the length of the valve core ring sleeve on the connecting shaft is adjustable.

25. The communication valve according to claim 24, wherein One end of the valve core is provided with a sleeve hole sleeved with the connecting shaft, and the other end thereof is provided with an adjusting screw hole communicated with the sleeve hole; The linkage valve also includes an adjusting screw, which is installed in the adjusting screw hole and contacts and cooperates with the end surface of the connecting shaft.

26. The communicating valve according to claim 22, characterized in that, The connecting valve further comprises a reset member, and the reset member is used to make the linkage valve have a tendency to reset to the initial position.

27. A pressure valve assembly, characterized in that, The pressure valve assembly comprises: Backwater valves; and The connecting valve according to any one of claims 16 to 26; Wherein, the water return valve has a hot water flow channel, a cold water flow channel and a one-way flow channel connecting the hot water flow channel and the cold water flow channel; Wherein, the docking flow channel of the connecting valve is connected to the inlet end of the one-way flow channel.

28. The pressure valve assembly according to claim 27, wherein The hot water flow channel has a first interface and a second interface, one of which is set to be blocked, and the other is connected to the docking flow channel of the connecting valve to connect the docking flow channel with the inlet end of the one-way flow channel.

29. The pressure valve assembly according to claim 28, wherein, The pressure valve assembly further comprises a sealing cover, which is adapted to seal one of the first interface and the second interface so that the other one is connected to the docking flow channel of the connecting valve.

30. A water supply system, characterized in that, The water supply system comprises: A hot water supply device, the hot water supply device having a water inlet pipe and a water outlet pipe; A water mixing device, wherein a hot water inlet end of the water mixing device is connected to the water outlet pipe through a hot water pipe, and a cold water inlet end of the water mixing device is connected to the water inlet pipe through a cold water pipe; and According to the pressure valve assembly as described in claim 27 or 29, the hot water channel of the connecting valve in the pressure valve assembly is connected to the hot water pipe, and the cold water flow channel of the return valve in the pressure valve assembly is connected to the cold water pipe.

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