阅读说明：本技术 回水阀和供水系统 (Water return valve and water supply system ) 是由 巴喜亮 梁国荣 于 2020-03-20 设计创作，主要内容包括：本发明公开一种回水阀和供水系统。回水阀包括阀体、流道开关和单向阀,阀体具有间隔设置的第一流道和第二流道、及连通第一流道与第二流道的第三流道；流道开关包括可活动地设于第三流道内的活动阀芯,活动阀芯上设有两端开口的过水流道,活动阀芯位于第一位置时,活动阀芯封堵第三流道,以使流道开关关闭第三流道；活动阀芯位于第二位置时,活动阀芯过水流道导通第三流道,以使流道开关打开第三流道；单向阀设于第三流道内。如此,通过在阀体上增设流道开关,以对第三流道的开闭进行控制,可在需要循环预热时打开第三流道,在防止误打开单向阀时关闭第三流道,从而可防止第一流道内的水通过单向阀而误串入第二流道内。(The invention discloses a water return valve and a water supply system. The water return valve comprises a valve body, a flow channel switch and a one-way valve, wherein the valve body is provided with a first flow channel, a second flow channel and a third flow channel, the first flow channel and the second flow channel are arranged at intervals, and the third flow channel is communicated with the first flow channel and the second flow channel; the flow channel switch comprises a movable valve core movably arranged in the third flow channel, the movable valve core is provided with a water passing flow channel with two open ends, and when the movable valve core is positioned at the first position, the movable valve core blocks the third flow channel so that the flow channel switch closes the third flow channel; when the movable valve core is positioned at the second position, the water passing channel of the movable valve core is communicated with the third channel, so that the third channel is opened by the channel switch; the check valve is arranged in the third flow passage. Therefore, the flow channel switch is additionally arranged on the valve body to control the opening and closing of the third flow channel, the third flow channel can be opened when the circulating preheating is needed, the third flow channel is closed when the one-way valve is prevented from being opened by mistake, and therefore the water in the first flow channel can be prevented from mistakenly entering the second flow channel through the one-way valve.)

1. A water return valve, comprising:

the valve body is provided with a flow passage, and the flow passage comprises a first flow passage, a second flow passage and a third flow passage, wherein the first flow passage and the second flow passage are arranged at intervals, and the third flow passage is communicated with the first flow passage and the second flow passage;

the flow channel switch comprises a movable valve core which is movably arranged in the third flow channel, a water passing flow channel with openings at two ends is arranged on the movable valve core, and when the movable valve core is positioned at a first position, the movable valve core blocks the third flow channel so as to enable the flow channel switch to close the third flow channel; when the movable valve core is located at the second position, the movable valve core conducts the third flow channel through the water passing flow channel, so that the flow channel switch opens the third flow channel; and

and the check valve is arranged in the third flow passage.

2. The water return valve according to claim 1 wherein said check valve is sealingly disposed within said water flow passage.

3. The water return valve according to claim 2 wherein said movable spool is rotatably disposed in said third flow passage.

4. The water return valve according to claim 3 wherein said valve body is provided with a switch mounting opening communicating with said third flow passage, and said movable spool is rotatably mounted in said third flow passage through said switch mounting opening.

5. The water return valve according to claim 4, wherein the valve body includes a switch fitting portion provided corresponding to the third flow path, the switch fitting portion is provided to protrude to one side, and the switch fitting opening is provided in the switch fitting portion.

6. The water return valve according to claim 5 wherein the movable valve element includes a blocking portion disposed in the third flow passage, and a driving portion connected to the blocking portion, the driving portion being rotatably and sealingly mounted in the switch mounting opening, and the water passing flow passage being disposed in the blocking portion.

7. The water return valve according to claim 6 wherein the blocking portion has a circular cross-section perpendicular to the axis of rotation thereof, and the third flow passage includes a blocking chamber for cooperation with the blocking portion.

8. The water return valve according to claim 7, wherein the blocking portion is cylindrical, truncated cone, or spherical.

9. The water return valve according to claim 1, wherein the first flow path includes a first section and a second section communicating with the first section, the first section is disposed at an angle to the second section, and a junction of the first section and the second section communicates with the third flow path; and/or (c) and/or,

the second flow channel comprises a third section and a fourth section communicated with the third section, the third section and the fourth section are arranged at an included angle, and the joint of the third section and the fourth section is communicated with the third flow channel.

10. The water return valve according to claim 1 wherein said movable spool is movably disposed in said third flow passage.

11. The water return valve according to any one of claims 1 to 10 wherein said flow path switch further comprises a driving member for driving said movable valve element to move in said flow path.

12. The water return valve of claim 11 wherein said drive assembly includes a motor.

13. The water return valve of claim 12 wherein said drive assembly further includes a power source for powering said motor; and/or (c) and/or,

the motor is a stepping motor or a servo motor.

14. The water return valve of claim 13 wherein said drive assembly further includes a control unit, said control unit being connected to said motor;

the control unit also comprises a communication unit which is used for being connected with the gas heating device; and/or (c) and/or,

the control unit further comprises a temperature detection unit, and the temperature detection unit is used for detecting the water temperature in the flow channel.

15. The water return valve according to any one of claims 1 through 10 wherein a step structure is formed in the water flow passage, the water return valve further comprising a retaining member, and the check valve is fixedly mounted between the step structure and the retaining member via the retaining member.

16. The water return valve according to claim 15 wherein said retainer is a snap spring.

17. The water return valve according to any one of claims 1 through 10 wherein said check valve comprises a check valve element, a resilient return member, a valve cover, and a valve housing open at both ends, said valve housing being sealingly mounted in said third flow passage; the one-way valve core is movably arranged in the valve shell so as to open or close the water flow passage; the valve cover is fixed at an opening of the valve shell; one end of the elastic resetting piece is connected with the valve cover, and the other end of the elastic resetting piece is connected with the one-way valve core, so that the one-way valve core has the tendency of resetting to the position for closing the water passing flow channel.

18. The water return valve of claim 17 wherein said valve housing is integral with said movable spool.

19. A water supply system, comprising:

a gas heating device;

the water outlet end is connected with the gas water heater through a cold water pipe, a hot water pipe and a water mixing device; and

a water return valve according to any one of claims 1 to 18 having a first flow path connected to the hot water pipe and a second flow path connected to the cold water pipe.

20. The water supply system of claim 19, wherein the gas heating device is a gas water heater or a gas wall-hanging stove.

21. A water supply system, comprising:

a gas heating device;

the water outlet end is connected with the gas water heater through a cold water pipe, a hot water pipe and a water mixing device;

the water return valve according to any one of claims 1 to 18, wherein a second flow passage of the water return valve is connected to a cold water pipe; and

and one end of the water return pipe is connected to the hot water pipe, and the other end of the water return pipe is connected to the first flow channel of the water return valve.

Technical Field

The invention relates to the technical field of zero-cold-water supply, in particular to a water return valve and a water supply system.

Background

The water supply system, such as a water supply system of a water heater or a water supply system of a wall-mounted boiler, is used for providing water for users, and generally comprises a gas heating device (such as a gas water heater or a wall-mounted boiler), a cold water pipe, a hot water pipe, a water mixing device and a water outlet end, wherein the water outlet end is connected with the gas heating device through the cold water pipe, the hot water pipe and the water mixing device.

In the related art, in order to make the water supply system have a zero-cold-water function, a water return valve having a check valve is usually added in the water supply system to form a water return waterway in the water supply system.

With the above water supply system, in some cases, for example, when the outlet end of the water supply system uses cold water alone, or when the outlet end of the water supply system uses hot water alone and pressure-increases the water supply, the hot water in the hot water pipe or the return water pipe may flow into the cold water pipe through the check valve.

Disclosure of Invention

The invention mainly aims to provide a water return valve, and aims to solve the technical problem that hot water in a hot water pipe or a water return pipe of a water supply system is easy to flow into a cold water pipe through the water return valve when the water supply system works in the related technology.

In order to achieve the above object, the present invention provides a check valve core of a water return valve, including:

the valve body one-way valve core is provided with a flow channel, and the flow channel comprises a first flow channel one-way valve core and a second flow channel one-way valve core which are arranged at intervals and a third flow channel one-way valve core which is communicated with the first flow channel one-way valve core and the second flow channel one-way valve core;

the flow channel switch one-way valve core comprises a movable valve core one-way valve core movably arranged in the third flow channel one-way valve core, the movable valve core one-way valve core is provided with a water passing flow channel one-way valve core with openings at two ends, and when the movable valve core one-way valve core is positioned at a first position, the movable valve core one-way valve core blocks the third flow channel one-way valve core so that the flow channel switch one-way valve core closes the third flow channel one-way valve core; when the movable valve core one-way valve core is located at the second position, the movable valve core one-way valve core conducts the third flow channel one-way valve core through the water passing flow channel one-way valve core, so that the flow channel switch one-way valve core opens the third flow channel one-way valve core; and

and the check valve core of the check valve is arranged in the check valve core of the third flow channel.

Optionally, the check valve core of the check valve is hermetically arranged in the check valve core of the water flow passage.

Optionally, the movable spool check valve element is rotatably disposed within the third flow passage check valve element.

Optionally, a switch mounting port check valve core communicated with the third flow passage check valve core is arranged on the valve body check valve core, and the movable valve core check valve core is rotatably mounted in the third flow passage check valve core through the switch mounting port check valve core.

Optionally, the valve body check valve core comprises a switch installation part check valve core arranged corresponding to the third flow passage check valve core, the switch installation part check valve core is convexly arranged towards one side, and the switch installation opening check valve core is arranged on the switch installation part check valve core.

Optionally, the movable valve element check valve element comprises a blocking part check valve element arranged in the third flow channel check valve element and a driving part check valve element connected with the blocking part check valve element, the driving part check valve element is rotatably and hermetically mounted in the switch mounting port check valve element, and the water passing channel check valve element is arranged in the blocking part check valve element.

Optionally, a section of the blocking portion check valve element perpendicular to the rotation axis thereof is circular, and the third flow channel check valve element includes a blocking cavity check valve element used in cooperation with the blocking portion check valve element.

Optionally, the blocking portion check valve core is cylindrical, or truncated cone-shaped or spherical.

Optionally, the first flow passage check valve core comprises a first section of check valve core and a second section of check valve core communicated with the first section of check valve core, the first section of check valve core and the second section of check valve core form an included angle, and the joint of the first section of check valve core and the second section of check valve core is communicated with the third flow passage check valve core; and/or (c) and/or,

the second flow passage one-way valve core comprises a third section one-way valve core and a fourth section one-way valve core communicated with the third section one-way valve core, the third section one-way valve core and the fourth section one-way valve core form an included angle, and the joint of the third section one-way valve core and the fourth section one-way valve core is communicated with the third flow passage one-way valve core.

Optionally, the movable valve core check valve core is movably arranged in the third flow channel check valve core.

Optionally, the flow channel switch check valve core further comprises a drive assembly check valve core, and the drive assembly check valve core is used for driving the movable valve core check valve core to move in the flow channel.

Optionally, the drive assembly check valve cartridge comprises a motor check valve cartridge.

Optionally, the drive assembly check valve core further comprises a power supply check valve core, and the power supply check valve core is used for supplying power to the motor check valve core; and/or (c) and/or,

the motor one-way valve core is a stepping motor one-way valve core or a servo motor one-way valve core.

Optionally, the drive assembly check valve core further comprises a control unit, and the control unit is connected with the motor check valve core;

the control unit also comprises a communication unit which is used for being connected with the one-way valve core of the gas heating device; and/or (c) and/or,

the control unit further comprises a temperature detection unit, and the temperature detection unit is used for detecting the water temperature in the flow channel.

Optionally, a step structure is formed in the water passing channel one-way valve core, the water return valve one-way valve core further comprises a limiting piece one-way valve core, and the one-way valve core is fixedly installed between the step structure and the limiting piece one-way valve core through the limiting piece one-way valve core.

Optionally, the one-way valve core of the limiting part is a snap spring.

Optionally, the check valve element comprises a check valve element, an elastic reset element check valve element, a valve cover check valve element and a valve casing check valve element with two open ends, and the valve casing check valve element is hermetically installed in the third flow passage check valve element; the check valve core of the check valve core is movably arranged in the check valve core of the valve shell so as to open or close the check valve core of the water passing flow channel; the valve cover one-way valve core is fixed at an opening of the valve shell one-way valve core; one end of the one-way valve core of the elastic reset piece is connected with the one-way valve core of the valve cover, and the other end of the one-way valve core is connected with the one-way valve core of the one-way valve core, so that the one-way valve core of the one-way valve core has the tendency of resetting to the position for closing the one-way valve core of the water flowing channel.

Optionally, the valve housing check valve element is integrally provided with the movable valve element check valve element.

The invention also provides a one-way valve core of a water supply system, which comprises:

a one-way valve core of the gas heating device;

the water outlet end one-way valve core is connected with the gas water heater through the cold water pipe one-way valve core, the hot water pipe one-way valve core and the water mixing device one-way valve core; and

according to the one-way valve core of the water return valve, the first flow passage one-way valve core of the water return valve is connected into the one-way valve core of the hot water pipe, and the second flow passage one-way valve core of the water return valve is connected into the one-way valve core of the cold water pipe.

Optionally, the one-way valve core of the gas heating device is a gas water heater or a gas wall-mounted boiler.

The invention also provides a one-way valve core of a water supply system, which comprises:

a one-way valve core of the gas heating device;

the water outlet end one-way valve core is connected with the gas water heater through the cold water pipe one-way valve core, the hot water pipe one-way valve core and the water mixing device one-way valve core;

the second flow channel check valve core of the return valve check valve core is connected to the cold water pipe check valve core; and

and one end of the return pipe one-way valve core is connected to the hot water pipe one-way valve core, and the other end of the return pipe one-way valve core is connected to the first flow channel one-way valve core of the return valve one-way valve core.

According to the water return valve, the flow channel switch is additionally arranged on the valve body to control the opening and closing of the third flow channel, the third flow channel can be opened when needed (such as when circulation preheating is needed), and the third flow channel is closed when not needed (such as when the one-way valve is prevented from being opened mistakenly), so that water in the first flow channel can be prevented from mistakenly entering the second flow channel through the one-way valve.

And the movable valve core can be plugged or communicated with the third flow channel through the water passing flow channel by driving the movable valve core to move in the third flow channel.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a unified embodiment of a water supply system according to the present invention;

FIG. 2 is a schematic structural view of another embodiment of the water supply system of the present invention;

FIG. 3 is a schematic structural diagram of a water return valve according to an embodiment of the present invention; wherein the movable valve core is positioned at a first position;

FIG. 4 is an enlarged view taken at A in FIG. 3;

FIG. 5 is a schematic view of another configuration of the trap of FIG. 3; wherein the movable valve core is located at a second position;

FIG. 6 is an enlarged view at B in FIG. 5;

FIG. 7 is a schematic structural diagram of another embodiment of a water return valve according to the present invention;

FIG. 8 is a schematic cross-sectional view of the water return valve of FIG. 7; wherein the movable valve core is located at a second position;

FIG. 9 is a schematic cross-sectional view of the water return valve of FIG. 7; wherein the movable valve core is positioned at a first position;

FIG. 10 is an enlarged view of a portion of the water return valve of FIG. 9;

FIG. 11 is a schematic structural diagram of a water return valve according to another embodiment of the present invention; wherein the movable valve core is located at a second position;

FIG. 12 is a schematic view of the structure of the water return valve of FIG. 11 in another state; wherein the movable valve core is located at the first position.

The reference numbers illustrate:

the implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that if the description of "first", "second", etc. is provided in the embodiment of the present invention, the description of "first", "second", etc. is only for descriptive purposes and is not to be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature.

In addition, the meaning of "and/or" appearing throughout is to include three juxtapositions, exemplified by "A and/or B" including either scheme A, or scheme B, or a scheme in which both A and B are satisfied.

The invention provides a water return valve and a water supply system.

As shown in fig. 1 and 2, the water return valve 100 is used in a water supply system 1000, that is, the water supply system 1000 includes the water return valve 100, so that the water supply system 1000 has a zero cold water function, and the water return valve 100 will be described in detail below with reference to the structure of the water supply system 1000. Optionally, the water supply system 1000 is a water heater water supply system 1000 (including but not limited to a gas water heater system) or a wall-hanging stove water supply system 1000, etc.

In an embodiment of the present invention, as shown in fig. 1 and 2, the water supply system 1000 further includes a gas heating device 200, a cold water pipe 300, a hot water pipe 400, a water mixing device 600, a water outlet 700, a water return valve 100, and the like, wherein the water outlet 700 is connected to the gas heating device 200 through the cold water pipe 300, the hot water pipe 400, and the water mixing device 600; the return valve 100 is installed in a water path of the water supply system 1000 to form a return water path for providing the water supply system 1000 with a zero-cold water function.

Specifically, as shown in fig. 1 and 2, the gas heating device 200 has a cold water inlet 201 and a hot water outlet 202, and the water mixing device 600 has a hot water inlet, a cold water inlet, and a water mixing outlet. Wherein, one end of the cold water pipe 300 and the cold water inlet 201 are both connected (i.e. communicated) with a water supply pipe (such as a tap water pipe, etc.), and the other end of the cold water pipe 300 is communicated with a cold water inlet; one end of the hot water pipe 400 is communicated with the hot water outlet 202, the other end is communicated with the hot water inlet, and the mixed water outlet is communicated with the water outlet end 700. Thus, by adjusting the mixing device 600, the outlet end 700 can send out cold water alone, hot water alone, or mixed water with proper temperature.

Optionally, a cold water joint is arranged at the cold water inlet 201; and/or a hot water joint is arranged at the hot water outlet 202.

Optionally, the water supply system 1000 includes a water inlet pipe 210, the cold water inlet 201 is communicated with the water supply pipe through the water inlet pipe 210, and the cold water pipe 300 is communicated with the water inlet pipe 210.

Optionally, the water outlet end 700 may be a shower or a faucet.

Optionally, the water outlet end 700 may be provided in plurality.

Optionally, the mixing device 600 is a mixing valve or other mixing device 600 with similar function to the mixing valve.

Alternatively, the gas heating device 200 is a gas water heater (such as an instant heating gas water heater or a thermal storage gas water heater) or a wall-mounted gas stove, and the gas water heater is taken as an example for description below.

In an embodiment of the present invention, as shown in fig. 3 to 12, the water return valve 100 includes a valve body 10, a check valve 20, and a flow path switch 30.

As shown in fig. 3 to 12, the valve body 10 has a flow passage, and the flow passage includes a first flow passage 11 and a second flow passage 12 which are arranged at an interval, and a third flow passage 13 which communicates the first flow passage 11 and the second flow passage 12.

As shown in fig. 3 to 12, the flow path switch 30 is disposed on the valve body 10 for opening or closing the third flow path 13. Specifically, the flow switch 30 may be a normally closed switch.

As shown in fig. 3 to 12, the check valve 20 is disposed in the third flow passage 13. The check valve 20 is used for allowing the water in the first flow passage 11 to flow to the second flow passage 12 through the third flow passage 13 after the check valve 20 is opened, and for preventing the water in the second flow passage 12 from flowing to the first flow passage 11; that is, the check valve 20 is used to unidirectionally introduce the water in the first flow passage 11 into the second flow passage 12.

The flow path switch 30 has an open state for opening the third flow path 13 when the check valve 20 is required to normally operate, and a closed state for closing the third flow path 13 when the check valve 20 is required to prevent erroneous opening.

The return valve 100 of the present invention is configured such that the flow path switch 30 is provided on the valve body 10 to control the opening and closing of the third flow path 13, so that the third flow path 13 can be opened when necessary (when the circulation preheating is necessary) and the third flow path 13 can be closed when not necessary, thereby preventing the water in the first flow path 11 from erroneously entering the second flow path 12 through the check valve 20.

The operation of the return valve 100 will be described in detail below with reference to the structure of the water supply system 1000.

In an embodiment of the water supply system 1000, the water supply system 1000 is not provided with the water return pipe 500; as shown in fig. 1, the first flow channel 11 is connected to a heat exchange pipe, the second flow channel 12 is connected to a cold water pipe 300, and the check valve 20 is used for unidirectionally guiding water in the first flow channel 11 into the second flow channel 12. When the outlet end 700 has a plurality of parts, the water return valve 100 may be optionally provided at the most distal outlet end 700.

Specifically, one end (e.g., end C in fig. 1) of the second flow passage 12 is communicated with the cold water inlet through a cold water pipe 300, and the other end (e.g., end D in fig. 1) of the second flow passage 12 is communicated with the water inlet pipe 210 through the cold water pipe 300; one end (e.g., end B in fig. 1) of the first flow passage 11 communicates with the hot water inlet through the hot water pipe 400, and the other end (e.g., end a in fig. 1) of the first flow passage 11 communicates with the hot water outlet 202 through the hot water pipe 400. In this way, a water return waterway in which the water return valve 100 is disposed may be formed among the hot water pipe 400, the first flow passage 11, the third flow passage 13, the second flow passage 12, the cold water pipe 300, the water inlet pipe 210, and the like.

As shown in fig. 1, the gas heating apparatus 200 further includes a water circulating pump 800, the water circulating pump 800 is disposed in the water return waterway, and the water circulating pump 800 is configured to drive water to flow in the water return waterway.

Alternatively, as shown in fig. 1, the circulation water pump 800 is disposed between the heat exchanger of the gas heating apparatus 200 and the cold water pipe 300. Specifically, the water circulation pump 800 is disposed between the heat exchanger of the gas heating apparatus 200 and the cold water inlet 201, and the water circulation pump 800 is further configured to suck cold water and/or pressurize and supply water.

Specifically, as shown in fig. 1, when the water supply system 1000 uses the zero-cold-water function for preheating, the flow switch 30 opens the third flow channel 13, so that the return water path can be conducted. As shown in fig. 1, at this time, the circulating water pump 800 pushes water in the return water path to flow, so that the water pressure in the first flow path 11 is increased, and thus the difference between the water pressure in the first flow path 11 and the water pressure in the second flow path 12 is increased, and at this time, as the flow path switch 30 opens the third flow path 13, the check valve 20 is opened, so that the water in the first flow path 11 flows into the second flow path 12, so that the water circularly flows in the return water path, and the water in the hot water pipe 400 and the like is circularly preheated, thereby realizing zero cold water. After the preheating is completed, the flow switch 30 may close the third flow channel 13 to close the water return valve 100 and the water return path.

When the outlet end 700 uses cold water alone, the flow switch 30 closes the third flow channel 13. At this time, the cold water flows out of the outlet end 700 through the second flow channel 12 and the mixing valve, so that the water pressure of the second flow channel 12 is reduced, but the flow channel switch 30 closes the third flow channel 13 to prevent the check valve 20 from being opened by mistake, so that the hot water in the first flow channel 11 can be prevented from flowing into the second flow channel 12 from the third flow channel 13 through the check valve 20, and the gas heating device 200 can be prevented from being started by mistake to perform the preheating cycle. That is, even if the water pressures of the cold water pipe 300 and the hot water pipe 400 are unbalanced, or even if the pressure difference is relatively large or particularly large, the check valve 20 is prevented from being opened by mistake because the flow path switch 30 closes the third flow path 13, so as to prevent water leakage.

When the water outlet end 700 is heated and pressurized (i.e., pressurized to supply hot water), the flow switch 30 closes the third flow channel 13. Specifically, the hot water in the hot water pipe 400 flows out from the water outlet end 700 through the first flow passage 11 and the water mixing valve, and at this time, the circulating water pump 800 may be used to increase the pressure to increase the water outlet amount and the water outlet speed of the hot water, so that the water pressure in the hot water pipe 400 is increased, and the pressure difference between the first flow passage 11 and the second flow passage 12 is also increased, but the flow passage switch 30 closes the third flow passage 13 to prevent the one-way valve 20 from being opened by mistake, so that the hot water in the first flow passage 11 is prevented from flowing into the second flow passage 12 from the third flow passage 13 through the one-way valve 20 in series, and the gas heating device 200 is prevented from being started by mistake to perform the preheating cycle.

Of course, the water return valve 100 may also be used in other water usage modes of the water supply system 1000, and it is not necessary to describe here any more, as long as the flow path switch 30 is enabled to open the third flow path 13 when the check valve 20 needs to work normally, and the flow path switch 30 is enabled to close the third flow path 13 when the check valve 20 needs to be prevented from being opened by mistake.

Of course, the above water return valve 100 may also be used in the water supply system 1000 having the water return pipe 500.

Specifically, in another embodiment of the water supply system 1000 according to the present invention, as shown in fig. 2, the water supply system 1000 includes a water return pipe 500, one end of the water return pipe 500 is connected to the hot water pipe 400, the other end of the water return pipe is connected to one end (e.g., end a in fig. 2) of the first flow passage 11, and the other end (e.g., end B in fig. 2) of the first flow passage 11 is blocked (e.g., by an end cap).

Wherein the second flow passage 12 is connected to the water inlet pipe 210 or the cold water pipe 300, and optionally, the second flow passage 12 is connected to the water inlet pipe 210; specifically, one end (e.g., end C in fig. 2) of the second flow passage 12 is communicated with the water inlet through the water inlet pipe 210, and the other end (e.g., end D in fig. 2) of the second flow passage 12 is communicated with the cold water pipe 300 through the water inlet pipe 210. Optionally, the water return valve 100 is disposed near the gas heating apparatus 200. And in this embodiment, when the outlet end 700 has a plurality of parts, the water return pipe 500 is connected to the farthest outlet end 700.

Thus, a return water path may be formed between the hot water pipe 400, the return pipe 500, the first flow passage 11, the third flow passage 13, the second flow passage 12, the inlet pipe 210, and the heat exchanger of the gas heating apparatus 200, etc.; wherein the water return valve 100 is arranged in the water return waterway.

In this embodiment, as shown in fig. 2, the gas heating apparatus 200 further includes a water circulating pump 800, the water circulating pump 800 is disposed in the water returning waterway, the water circulating pump 800 is configured to drive water to flow in the water returning waterway, and the position where the water circulating pump 800 is disposed may refer to the previous embodiment, which is not described herein.

In this embodiment, when the water supply system 1000 is preheated using the zero cold water function, the flow channel switch 30 opens the third flow channel 13 to enable the water return waterway to be conducted. As shown in fig. 2, the circulating water pump 800 pushes water in the return water path to flow, so that the water pressure in the first flow path 11 is increased, and thus the difference between the water pressure in the first flow path 11 and the water pressure in the second flow path 12 is increased, at this time, as the flow path switch 30 opens the third flow path 13, the check valve 20 is opened, so that the water in the first flow path 11 flows into the second flow path 12, so that the water circularly flows in the return water path, and the water in the hot water pipe 400 and the like is circularly preheated, thereby realizing zero cold water. After the preheating is completed, the flow switch 30 may close the third flow channel 13 to close the water return valve 100 and the water return path.

It is understood that, in this embodiment, when the hot water is pressurized or the check valve 20 may be opened by mistake, the flow switch may be made to close the third flow channel 13, so as to prevent the hot water in the first flow channel 11 from flowing from the third flow channel 13 into the second flow channel 12 through the check valve 20.

It is understood that in the above embodiment, the first flow passage 11 is a hot water end of the water return valve 100, and the second flow passage 12 is a cold water end of the water return valve 100.

In combination with the above embodiments, the water return valve 100 of the present invention can control the opening and closing of the third flow channel 13 by adding the flow channel switch 30 to the valve body 10, so that the third flow channel 13 can be opened when the check valve 20 needs to operate normally (if circulation preheating is needed), and the third flow channel 13 can be closed when the check valve 20 is not needed (if the check valve 20 is prevented from being opened by mistake), thereby preventing the water in the first flow channel 11 from entering the second flow channel 12 by mistake through the check valve 20.

Further, as shown in fig. 3 to 12, the flow path switch 30 includes a movable valve core 31, the movable valve core 31 is movably disposed in the flow path, and when the movable valve core 31 is located at the first position, the flow path switch 30 closes the third flow path 13; when the movable spool 31 is in the second position, the flow path switch 30 opens the third flow path 13. In this way, the operating state of the flow path switch 30 can be controlled by controlling the movement of the movable spool 31.

Specifically, the movable valve element 31 is movable between a first position and a second position to switch the flow path switch 30 between opening and closing the third flow path 13.

In an embodiment, the moving mode of the movable valve core 31 has a plurality of modes, such as the movable valve core 31 is movably disposed in the flow passage, or the movable valve core 31 is rotatably disposed in the flow passage, etc., which will be exemplified below.

Further, as shown in fig. 3 and 5, the movable valve core 31 is movably disposed in the flow passage, so that the movable valve core 31 has a first position and a second position. In this manner, the movable spool 31 is movably disposed in the flow passage, which facilitates control of the movement of the movable spool 31.

Further, as shown in fig. 3 and 5, a switch mounting port 14 communicating with the flow passage is provided on the valve body 10, and the movable valve element 31 is movably mounted in the flow passage through the switch mounting port 14 for moving the movable valve element 31 between the first position and the second position. Specifically, the movable valve core 31 is movably and hermetically installed in the switch installation port 14 to prevent the flow passage from leaking.

By providing the switch attachment opening 14 in this manner, on the one hand, the movable valve body 31 can be attached to the flow path through the switch attachment opening 14; on the other hand, the movable valve element 31 may be moved in the flow path by moving the movable valve element 31 in the switch mounting port 14, so that the movement of the movable valve element 31 is controlled, and the structure of the valve body 10 is simplified.

Of course, in other embodiments, a structure (such as a sliding ring, etc.) that is movably and sealingly engaged with the movable valve core 31 may be directly disposed in the flow passage.

Further, as shown in fig. 3 and 5, the switch mounting port 14 is communicated with the second flow channel 12, and the switch mounting port 14 is disposed corresponding to the opening of the third flow channel 13. In this way, the movable valve element 31 may be extended into the third flow passage 13 through the second flow passage 12, so that the movable valve element 31 opens or closes the third flow passage 13.

Further, as shown in fig. 3 to 6, the water return valve 100 further includes a first limiting sleeve 40, the first limiting sleeve 40 is disposed on one side of the check valve 20 facing the second flow channel 12, and the first limiting sleeve 40 is hermetically installed in the third flow channel 13.

The movable valve core 31 moves in a direction close to or far away from the first limit sleeve 40, and in the first position, the movable valve core 31 blocks the first limit sleeve 40 to close the third flow channel 13; in the second position, the movable spool 31 is away from the first stop collar 40 to open the first stop collar 40 and the third flow passage 13. In this manner, opening or closing of the third flow passage 13 can be achieved. Of course, a structure that engages with the movable valve body 31 may be provided directly on the inner wall of the third flow passage 13.

Specifically, as shown in fig. 3 to 6, a sealing ring protrusion 41 is disposed on an inner wall surface of the first position limiting sleeve 40, the movable valve element 31 is disposed on one side of the sealing ring protrusion 41 facing the second flow channel 12, a blocking ring protrusion 3111 is disposed at one end of the movable valve element 31, and in the first position, the blocking ring protrusion 3111 blocks the sealing ring protrusion 41, so that the movable valve element 31 blocks the first position limiting sleeve 40. In detail, in the first position, the seal ring protrusion 3111 is in sealing contact with the seal ring protrusion 41 so that the seal ring protrusion 3111 seals the seal ring protrusion 41. Thus, the sealing property can be improved.

As shown in fig. 3 to 6, the sealing ring protrusion 41 has a first annular sealing surface 411 facing the second flow channel 12, the sealing ring protrusion 3111 is provided with a second annular sealing surface 31111 cooperating with the first annular sealing surface 411, and the first annular sealing surface 411 is arranged in a tapered manner in a direction from the first flow channel 11 to the second flow channel 12. In this way, it is possible to facilitate guiding the second annular seal surface 31111 into abutment with the first annular seal surface 411, so as to reduce the control accuracy of the movable spool 31; it is also possible to increase the contact area of second annular seal surface 31111 with first annular seal surface 411 in the second position to enhance the sealing effect.

Alternatively, the longitudinal cross-section of first annular seal surface 411 (the cross-section through its centerline) is two sloped lines or two curved lines.

Optionally, a first sealing ring (not shown) is further disposed between the outer periphery of the first stop collar 40 and the inner wall surface of the third flow channel 13 to improve the installation sealing performance of the first stop collar 40.

Specifically, a first accommodating ring groove is formed in the outer peripheral surface of the first limiting sleeve 40, and the first sealing ring is sleeved in the first accommodating ring groove. Optionally, a first receiving ring groove is provided for the sealing ring protrusion 41.

Of course, in other embodiments, the seal ring protrusion 3111 may not be provided, and one end portion of the movable valve element 31 may be directly engaged with the seal ring protrusion 41.

Further, as shown in fig. 3 to 6, the water return valve 100 further includes a second limiting sleeve 50, the second limiting sleeve 50 is hermetically installed in the switch installation port 14, and the movable valve core 31 is movably and hermetically installed in the second limiting sleeve 50. In this way, it is possible to avoid providing a fitting structure with the movable valve body 31 directly on the inner wall of the switch mounting port 14.

Optionally, a second sealing ring (not shown) is further disposed between the outer periphery of the second limiting sleeve 50 and the inner wall surface of the switch mounting opening 14, so as to improve the mounting sealing performance of the second limiting sleeve 50.

Specifically, a second accommodating ring groove is formed in the outer peripheral surface of the second limiting sleeve 50, and the second sealing ring is sleeved in the second accommodating ring groove.

Further, as shown in fig. 3 to 6, the movable valve core 31 is rotatably connected to the second position-limiting sleeve 50 by a screw-fit structure, so that the movable valve core 31 is movably installed in the second position-limiting sleeve 50.

Specifically, the outer peripheral surface of the movable valve core 31 is provided with an external thread, the inner wall surface of the second limiting sleeve 50 is provided with an internal thread, and the movable valve core 31 and the second limiting sleeve 50 are in threaded connection through the matching of the external thread and the internal thread, so that the movable valve core 31 can be controlled to move by driving the movable valve core 31 to rotate, and the connection sealing performance of the movable valve core 31 and the second limiting sleeve 50 can be improved.

Further, as shown in fig. 3 to 6, the movable valve core 31 includes a thicker section 312 and a thinner section 311 connected to the thicker section 312, the thicker section 312 is movably installed in the second position-limiting sleeve 50, and the thinner section 311 is disposed in the flow passage for blocking the first position-limiting sleeve 40. Specifically, the plugging ring protrusion 3111 is arranged on the thinner section 311, and the thicker section 312 is connected in the second limiting sleeve 50 in a threaded manner.

Thus, the movable valve core 31 comprises the thicker section 312 and the thinner section 311, and the thicker section 312 is movably installed in the second position-limiting sleeve 50, so that the movable valve core 31 can be conveniently controlled, and the thinner section 311 is arranged in the flow passage, so that the movable valve core 31 is prevented from excessively influencing the flow of water in the flow passage.

Alternatively, the thinner section 311 has a water gap directly with the inner wall surface of the second flow channel 12.

Optionally, a third sealing ring (not shown) is further disposed between the outer peripheral surface of the thicker section 312 and the inner wall surface (i.e., the inner annular surface) of the second stop collar 50, so as to improve the installation sealing performance. Specifically, a third accommodating ring groove is formed in the outer peripheral surface of the thicker section 312, and a third sealing ring is sleeved in the third accommodating ring groove.

Further, as shown in fig. 3 to 6, the valve body 10 includes a switch mounting portion 15, the switch mounting portion 15 is protruded toward one side, and the switch mounting port 14 is formed on the switch mounting portion 15. Thus, the installation space can be increased.

Further, as shown in fig. 3 to 6, the second position limiting sleeve 50 includes an insertion portion 51 inserted into the switch mounting opening 14, and a positioning portion 52 connected to the insertion portion 51, and the positioning portion 52 is disposed outside the switch mounting opening 14 and abuts against the opening end of the switch mounting portion 15 to position and limit the mounting of the second position limiting sleeve 50.

Further, as shown in fig. 3 to 6, a step structure (not shown) is formed in the third flow passage 13, and the check valve 20 is fixedly installed between the step structure and the first stop collar 40.

Specifically, as shown in fig. 3-6, the check valve 20 includes a check valve element 21 (i.e., a blocking member), an elastic restoring member 24, a valve cover 23, and a valve housing 22 with two open ends.

Wherein the valve housing 22 is sealingly mounted in the third flow passage 13. Specifically, the valve housing 22 is fixedly mounted between the stepped structure and the first stop collar 40, such that the check valve 20 is fixedly mounted between the stepped structure and the first stop collar 40.

Optionally, a fourth sealing ring (not shown) is further provided between the outer peripheral surface of the valve housing 22 and the inner wall surface of the third flow passage 13 to improve the sealing property during installation. Specifically, a fourth accommodating ring groove is formed in the outer peripheral surface of the valve housing 22, and a fourth sealing ring is sleeved in the fourth accommodating ring groove.

Wherein the check valve spool 21 is movably provided in the valve housing 22 to open or close the check valve 20. Specifically, the inner wall surface of the valve casing 22 is provided with a limit ring protrusion 221, and one end of the check valve element 21 can be abutted against the limit ring protrusion 221 to plug the valve casing 22 so as to close the check valve 20. Optionally, one end of the check valve spool 21 is provided with an annular abutment portion 211 for abutting against the stopper ring projection 221. Optionally, the annular abutment 211 is cap-shaped.

Alternatively, the valve housing 22 is partially recessed to form a fourth receiving ring groove on the outer circumferential surface of the valve housing 22 and a retainer ring protrusion 221 on the inner wall surface of the valve housing 22.

Further, as shown in fig. 4, a water passage is provided on the inner wall surface of the valve housing 22, the water passage is provided on one side of the limit ring protrusion 221 facing the second flow channel 12, and when the annular abutting portion 211 is far away from the limit ring protrusion 221, the water passage communicates the first flow channel 11 and the second flow channel 12, so that the check valve 20 opens the third flow channel 13.

Wherein the valve cover 23 is fixed to an opening of the valve housing 22; the elastic restoring member 24 has one end connected to the valve cover 23 and the other end connected to the check valve body 21 (specifically, the annular abutting portion 211), so that the check valve body 21 tends to be restored to a position closing the third flow passage 13.

It should be particularly noted herein that when assembling the water return valve 100, the check valve 20 can now be installed into the housing from the switch mounting opening 14, and then the first position-limiting sleeve 40 is installed into the housing from the switch mounting opening 14, and the check valve 20 can be limited between the step structure and the first position-limiting sleeve 40; the second stop collar 50 and the movable valve core 31 are then mounted to the valve body 10.

Optionally, a third position-limiting sleeve (not shown) may be further disposed between the first position-limiting sleeve 40 and the second position-limiting sleeve 50 to improve the installation stability of the first position-limiting sleeve 40. It can be understood that the third limiting sleeve is disposed in the second flow channel 12, and a water passing structure is formed on the third limiting sleeve and/or between the third limiting sleeve and the inner wall surface of the second flow channel 12.

Further, as shown in fig. 3, the flow channel switch 30 further includes a driving assembly 32, and the driving assembly 32 is configured to drive the movable valve core 31 to move in the flow channel. In this way, an automated control of the flow channel switch 30 can be achieved.

Further, as shown in fig. 3, the driving assembly 32 includes a motor 321. In this way, the movable valve core 31 can be driven to move by the motor 321.

Specifically, the motor 321 is mounted on the switch mounting portion 15.

In the present embodiment, the shaft of the motor 321 is connected with the movable valve core 31 through a spline structure, so as to drive the movable valve core 31 to rotate so as to move in the switch mounting port 14.

In this embodiment, optionally, the motor 321 is a stepping motor 321. Of course, in other embodiments, the motor 321 may be a servo motor 321 or other electromagnetic principle elements capable of realizing rotation.

Further, as shown in fig. 7, the driving assembly 32 further includes a power source 322, and the power source 322 is used for supplying power to the motor 321 and other components. Alternatively, the power source 322 may be a lithium battery or a dry battery. Of course, in other embodiments, the power supply may be provided by the plug-in power supply 322.

It should be noted that, in the water return valve 100 of the present invention, when the flow path switch 30 closes the third flow path 13, it is not necessary to keep the power on all the time, but only needs to power on when the movable valve core 31 is driven to move, i.e. only power is consumed during the operation, and the opening or closing process is more power-saving.

Further, the driving assembly 32 further comprises a control unit, and the control unit is connected with the motor 321.

The control unit further comprises a communication unit, and the communication unit is used for being connected with the gas heating device 200 so as to realize linkage of the flow channel switch 30 and the gas heating device 200. Optionally, the communication unit includes, but is not limited to, RF, WIFI, bluetooth, or the like.

Optionally, the control unit comprises a control board 323; the communication unit is a chip to be connected to the control board 323.

Optionally, the valve body 10 includes an auxiliary mounting portion for mounting a control unit and a power source 322.

Of course, in other embodiments, the driving assembly 32 may be configured in other structures, for example, the driving assembly 32 includes a hydraulic cylinder for driving the movable valve core 31 to move; and so on.

Optionally, the control unit further includes a temperature detection unit, and the temperature detection unit is configured to detect a temperature of water in the flow channel to detect whether hot water reaches the flow channel.

Of course, in other embodiments, the switch mounting port 14 and the movable valve core 31 may be disposed at other positions.

For example, in a modified embodiment of the above embodiment, the switch mounting port 14 is provided on the valve body 10 and communicates with the third flow passage 13, the switch mounting port 14 is located on one side of the check valve 20 (e.g., on the side facing the first flow passage 11 or on the side facing the second flow passage 12), and the movable valve body 31 is movably (e.g., rotatably or movably) mounted in the third flow passage 13 through the switch mounting port 14, so as to move the movable valve body 31 between the first position and the second position.

As another example, in another modified embodiment of the above embodiment, the switch mounting port 14 is disposed on the valve body 10 and is communicated with the first flow passage 11, the switch mounting port 14 is disposed corresponding to an opening of the third flow passage 13, and the movable valve core 31 is movably mounted in the first flow passage 11 through the switch mounting port 14, so as to move the movable valve core 31 between the first position and the second position.

Here, it should be noted that, in the above embodiment, the water return valve 100 also has the advantage that when the flow path switch 30 closes the third flow path 13, it can cooperate with the one-way valve 20 to form the effect of blocking the third flow path 13 in multiple stages, so that the closing effect on the third flow path 13 can be improved, and the water cross-over prevention effect can be improved.

Further, the first flow channel 11 may be selected from a straight flow channel, a curved flow channel, a segmented flow channel, and the like.

Further, the second flow channel 12 may be selected from a straight flow channel, a curved flow channel, a segmented flow channel, and the like.

However, the flow path switch 30 and the check valve 20 may be provided in other forms, which will be described in detail below.

In another embodiment of the water return valve 100 according to the present invention, as shown in fig. 7-10, the flow path switch 30 includes a movable valve core 31 movably disposed in the third flow path 13, a water passing flow path 3161 with two open ends is disposed on the movable valve core 31, and when the movable valve core 31 is located at a first position, the movable valve core 31 blocks the third flow path 13, so that the flow path switch 30 closes the third flow path 13; when the movable valve core 31 is located at the second position, the movable valve core 31 conducts the third flow channel 13 through the water flowing channel 3161, so that the flow channel switch 30 opens the third flow channel 13. Thus, by driving the movable valve body 31 to move in the third flow path 13, the movable valve body 31 can block or open the third flow path 13 through the water passing flow path 3161.

In this embodiment, further, as shown in fig. 7-10, the check valve 20 is sealingly disposed in the water flow passage 3161. In this manner, the check valve 20 may be made to move with the movable spool 31 to further reduce the risk of the check valve 20 being opened by mistake. Of course, in other embodiments, the check valve 20 and the movable valve core 31 may be disposed at a distance to form a multi-stage blocking effect.

Alternatively, the third flow channel 13 may be a straight flow channel, a curved flow channel, or the like, and the water passing flow channel 3161 may be a straight flow channel, a curved flow channel, or the like. Of course, providing both the third flow channel 13 and the water passing flow channel 3161 as straight flow channels may facilitate simplifying the structure of the water return valve 100. For convenience of description of the structure of the water return valve 100, the third flow channel 13 and the water flow channel 3161 are used as a straight flow channel, but this is not intended to limit the scope of the present invention.

In this embodiment, further, as shown in fig. 7 to 10, the movable spool 31 is rotatably provided in the third flow passage 13. Thus, when the movable valve element 31 is in the first position, the water passing channel 3161 is disposed at an angle (including but not limited to 90 degrees, such as at an angle between 60 and 90 degrees) with respect to the third flow channel 13 (i.e., the center line of the water passing channel 3161 is disposed at an angle with respect to the center line of the third flow channel 13), such that the movable valve element 31 blocks the third flow channel 13. When the movable valve core 31 is located at the second position, the water passing channel 3161 and the third flow channel 13 are arranged in substantially the same direction (or at a small angle, such as other angles between 0 and 35 degrees), so that the movable valve core 31 conducts the third flow channel 13 through the water passing channel 3161.

In this embodiment, optionally, in the first position, the included angle between the water passing flow channel 3161 and the third flow channel 13 is substantially 90 degrees; in the second position, the water passing flow channel 3161 is disposed substantially in the same direction or in parallel with the third flow channel 13. Thus, the movable valve element 31 can be switched between the first position and the second position by rotating it substantially 90 degrees.

In this embodiment, in order to facilitate installation and control of the movable valve body 31, a switch installation port 14 may also be provided on the valve body 10, the switch installation port 14 communicating with the third flow passage 13, so that the movable valve body 31 is rotatably installed in the third flow passage 13 through the switch installation port 14.

In this embodiment, as shown in fig. 7 to 10, the valve body 10 includes a switch mounting portion 15 disposed corresponding to the third flow passage 13, the switch mounting portion 15 protrudes to one side, and the switch mounting opening 14 is disposed on the switch mounting portion 15. So, can increase installation space, reduce the installation degree of difficulty, improve installation stability.

In this embodiment, as shown in fig. 7 to 10, the movable valve body 31 includes a blocking portion 316 provided in the third flow passage 13, and a driving portion 317 connected to the blocking portion 316, the water passing passage 3161 is provided in the blocking portion 316, and the driving portion 317 is rotatably and hermetically installed in the switch installation port 14. In this way, the movable valve body 31 is rotatably provided in the third flow passage 13, and the driving portion 317 can drive the closing portion 316 to rotate.

In this embodiment, as shown in fig. 7 to 10, a fifth seal ring is provided between the driving portion 317 and the inner wall surface of the switch attachment port 14.

In this embodiment, further, the cross section of the blocking portion 316 perpendicular to the rotation axis thereof is circular, and the third flow passage 13 includes a blocking cavity 131 used in cooperation with the blocking portion 316. In this way, the blocking portion 316 can be rotatably sealed in the blocking cavity 131.

In operation, in the first position, the outer surface of the blocking portion 316 abuts against the inner wall surface of the blocking chamber 131 to block the third flow channel 13; in the second position, the outer surface of the blocking portion 316 abuts against the inner wall surface of the blocking chamber 131 so that water flows through the water flow passage 3161.

Optionally, the shape of the occlusion cavity 131 is adapted to the shape of the occlusion part 316.

In this embodiment, the blocking portion 316 may be cylindrical, truncated cone, spherical, or the like. Specifically, the blocking portion 316 may be a cylinder, and the blocking cavity 131 may be a cylinder, so that the structures of the blocking portion 316 and the valve body 10 may be simplified, and the assembly of the water return valve 100 may be facilitated.

In this embodiment, as shown in fig. 7 to 10, the structure of the driving portion 317 may refer to the structure of the blocking portion 316, and a detailed description thereof is omitted here. Optionally, the driving portion 317 is cylindrical.

In this embodiment, as shown in fig. 7 to 10, the flow channel switch 30 further includes a driving assembly 32, and the driving assembly 32 is used for driving the movable valve core 31 to move in the flow channel.

In this embodiment, specifically, as shown in fig. 7 to 10, the driving assembly 32 includes a motor 321, the motor 321 is mounted on the switch mounting portion 15, and a shaft of the motor 321 is connected to the driving portion 317 for driving the movable valve core 31 to rotate.

In this embodiment, the type and power supply mode of the motor 321, and the communication and control mode thereof can be referred to the above embodiments, and are not described in detail herein.

Of course, in other embodiments, the movable valve core 31 may be driven to rotate by other means, such as a belt transmission assembly, a gear-rack transmission assembly, etc., and need not be described in detail herein.

In this embodiment, optionally, as shown in fig. 7 to 10, the first flow channel 11 includes a first section 111 and a second section 112 communicating with the first section 111, the first section 111 is disposed at an angle to the second section 112, and a connection between the first section 111 and the second section 112 communicates with the third flow channel 13. In this manner, an increase in the length of the first flow passage 11 may be facilitated or a decrease in the volume of the first flow passage 11 may be facilitated for the same length.

In this embodiment, optionally, as shown in fig. 7 to 10, the second flow channel 12 includes a third segment 121 and a fourth segment 122 communicated with the third segment 121, the third segment 121 and the fourth segment 122 are disposed at an included angle, and a connection between the third segment 121 and the fourth segment 122 is communicated with the third flow channel 13. In this manner, an increase in the length of the second flow passage 12 may be facilitated or a decrease in the volume of the second flow passage 12 may be facilitated for the same length.

In this embodiment, optionally, as shown in fig. 7 to 10, the length of the flow channel of the third flow channel 13 is slightly greater than or equal to the length of the flow channel of the blocking cavity 131. Through the arrangement of the first flow channel 11, the second flow channel 12 and the third flow channel 13, the structure of the valve body 10 can be simplified, and the miniaturization design of the valve body 10 is facilitated.

In this embodiment, the structure of the check valve 20 can refer to the above embodiments, and a detailed description thereof is not necessary. It should be noted that when the check valve 20 is installed in the water flow path 3161, the installation manner may be selected as follows: a step structure is formed in the water flowing channel 3161, the water return valve 100 further includes a limiting member 60, and the check valve 20 is fixedly installed between the step structure and the limiting member 60 through the limiting member 60; the limiting member 60 can be a snap spring. In this manner, the assembly process of the check valve 20 can be simplified.

In this embodiment, the valve housing 22 is optionally integral with the movable valve core 31 when the one-way valve 20 is installed in the flow passage 3161. In this way, the corresponding assembly steps can at least be reduced.

In still another embodiment of the return valve 100 of the present invention, as shown in fig. 11 and 12, the movable spool 31 is movably provided in the third flow passage 13 so that: when the movable valve core 31 is located at the first position, the movable valve core 31 blocks the third flow channel 13, so that the flow channel switch 30 closes the third flow channel 13; when the movable valve core 31 is located at the second position, the movable valve core 31 conducts the third flow channel 13 through the water flowing channel 3161, so that the flow channel switch 30 opens the third flow channel 13.

In this embodiment, optionally, as shown in fig. 11 and 12, an avoidance cavity communicated with the third flow channel 13 is provided on the valve body 10, the avoidance cavity includes a first avoidance cavity and a second avoidance cavity respectively provided at two sides of the third flow channel 13, the movable valve core 31 includes a blocking part and a conducting part, the water passing channel 3161 is provided on the conducting part, in the first position, the conducting part is located in the first avoidance cavity, and the blocking part is located in the third flow channel 13 to block the third flow channel 13, so that the flow channel switch 30 closes the third flow channel 13; in the second position, the blocking portion is located in the second avoiding chamber, and the conducting portion is located in the third flow channel 13 to conduct the third flow channel 13 through the water passing flow channel 3161, so that the flow channel switch 30 opens the third flow channel 13.

It should be emphasized here that the water return valve 100 in the above disclosed embodiment has at least the following advantages:

1. by adding the flow path switch 30 to the valve body 10, the water leakage prevention effect can be achieved (for example, in the case of pressurizing and feeding hot water, separately feeding cold water, and the like in the water supply system 1000).

2. Only power is consumed when the motor 321 operates, and a battery (such as a lithium battery or a dry battery) is used for supplying power, so that the service life is long.

3. The motor 321 is adopted to drive the movable valve core 31 to move, so that the effects that the valve core is opened when the third flow channel 13 is opened and the valve core is closed when the third flow channel 13 is closed can be realized, namely, the reaction is not delayed and is rapid.

The invention also proposes a water supply system comprising:

a gas heating device;

the water outlet end is connected with the gas water heater through a cold water pipe, a hot water pipe and a water mixing device; and

and a first flow passage of the water return valve is connected to the hot water pipe, and a second flow passage of the water return valve is connected to the cold water pipe.

The specific structure of the water return valve refers to the above embodiments, and the water supply system of the present invention adopts all technical solutions of all the above embodiments, so that the water return valve at least has all the beneficial effects brought by the technical solutions of the above embodiments, and details are not repeated herein.

Wherein, the gas heating device is a gas water heater or a gas wall-hanging stove.

The invention also proposes a water supply system comprising:

a gas heating device;

the water outlet end is connected with the gas water heater through a cold water pipe, a hot water pipe and a water mixing device;

the second flow passage of the water return valve is connected to the cold water pipe; and

and one end of the water return pipe is connected to the hot water pipe, and the other end of the water return pipe is connected to the first flow channel of the water return valve.

The specific structure of the water return valve refers to the above embodiments, and the water supply system of the present invention adopts all technical solutions of all the above embodiments, so that the water return valve at least has all the beneficial effects brought by the technical solutions of the above embodiments, and details are not repeated herein.

Wherein, the gas heating device is a gas water heater or a gas wall-hanging stove.

The above description is only an alternative embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.