Three-way electromagnetic switching valve and double-circulation gas water heater

Abstract

A three-way electromagnetic switching valve comprises a valve body, a positioning sleeve, a valve rod, a valve core, a coil, an isolating sleeve and a spring. The valve body has a water inlet port, a first water outlet port, a second water outlet port, a first valve port and a second valve port. The first valve port is communicated with the first water outlet port, the second valve port is communicated with the second water outlet port, and the water inlet port is communicated with the first valve port and the second valve port. The valve rod is movably arranged in the valve cavity of the valve body and the front end of the valve rod is limited by the positioning sleeve. The valve core is arranged in the middle of the valve rod and can open and close the first valve port and the second valve port. The application also discloses a double-circulation gas water heater. The three-way electromagnetic switching valve is used to switch the inner circulation and the outer circulation, and the first use of hot water can be ensured, and the inner circulation can ensure that no cold water phenomenon occurs when water is used again.

Description

Technical Field

[0001] This invention relates to a three-way valve, and more particularly to a two-position three-way solenoid valve, applicable to gas water heaters. This invention also relates to a gas water heater. Background Technology

[0002] The phenomenon of "intercalated water" refers to the experience of encountering a segment of cold water when a user turns off the water after using it normally and then turns it back on. This occurs because the water heater undergoes an ignition process between being turned off and restarted, which typically takes about 2 seconds. During this time, only cold water flows through the water heater. When the user turns the water back on, they will inevitably experience this cold water. Due to the length of the pipes, there is a time delay in the arrival of this cold water segment at the user's end. Therefore, it feels like the water is still hot after being turned on again, but there is a sudden segment of cold water mixed in, hence the term "intercalated cold water." This phenomenon is particularly noticeable in winter due to the lower inlet water temperature.

[0003] Generally, zero-cold-water water heaters use an external circulation system. In this external circulation state, the water temperature decreases throughout the entire loop. For example, if the outlet temperature (Tout) is Tset (42℃), then the inlet temperature (Tin) is approximately 32℃. Because the water heater has a minimum heating power during circulation, and due to the long external circulation pipes, there are significant heat dissipation issues, it's not sufficient to simply circulate water to even out the water temperature. This is especially problematic in winter, causing a rapid drop in pipe temperature. Therefore, even in circulation heating mode, there will inevitably be a temperature difference between the outlet and inlet water temperatures. Based on the current minimum power of most gas water heaters, the temperature difference between the inlet and outlet is generally at least 10℃. Therefore, users will experience at least a 10℃ temperature difference when turning the water off and on again.

[0004] Moreover, using this external circulation function to alleviate the "intercalated water" phenomenon is very energy-intensive and ineffective. This is because the external circulation pipe is generally quite long; for a 100㎡ living environment, the pipe length is about 50m. Including the heat dissipation of the pipe, it takes at least 3 minutes to circulate and heat the water in the entire pipe. If the inlet water temperature needs to be maintained at a high level 24 hours a day in winter, the gas consumption will be unacceptable to users. Summary of the Invention

[0005] The first technical problem to be solved by the present invention is to provide a three-way electromagnetic switching valve that can basically eliminate the phenomenon of water sandwiching, in view of the above-mentioned technical status quo.

[0006] The second technical problem to be solved by the present invention is to provide a dual-circulation gas water heater that can basically eliminate the phenomenon of intercalated water, in view of the above-mentioned technical status quo.

[0007] The technical solution adopted by the present invention to solve the first technical problem mentioned above is: a three-way electromagnetic switching valve, characterized in that it includes...

[0008] The valve body has an inlet port, a first outlet port, a second outlet port, a first valve port, and a second valve port. The first valve port is connected to the first outlet port, and the second valve port is connected to the second outlet port. The inlet port can also be connected to the first and second valve ports.

[0009] A positioning sleeve is provided inside the valve cavity of the aforementioned valve body;

[0010] The valve stem is axially movable within the valve cavity of the aforementioned valve body, and its front end is constrained by the aforementioned positioning sleeve.

[0011] The valve core is located in the middle of the aforementioned valve stem and can open and close the first valve port and the second valve port.

[0012] A coil is located at the rear end of the aforementioned valve body and has an internal cavity;

[0013] An isolation sleeve, disposed within the inner cavity of the aforementioned coil and having an axial cavity into which the rear end of the valve stem extends; and

[0014] A spring is located inside the aforementioned positioning sleeve and acts on the valve stem;

[0015] When the coil is not energized, the valve core is moved backward by the spring, closing the second valve port and simultaneously opening the first valve port.

[0016] When the coil is energized, the valve stem is acted upon by the magnetic field force of the coil and drives the valve core to move forward. The valve core closes the first valve port and opens the second valve port.

[0017] Preferably, the isolation sleeve includes a main body and an extension portion that protrudes rearward from the main body. The main body is sealed within the valve body cavity, the extension portion is located within the coil cavity, and the spring is located within the axial cavity of the extension portion.

[0018] Preferably, the valve core and valve stem are integrally injection molded.

[0019] Preferably, the positioning sleeve is cylindrical and includes a front support portion, a rear support portion, and a connecting portion located between the front support portion and the rear support portion. The front support portion and the rear support portion are respectively formed with a front through hole and a rear through hole for the valve stem to pass through. The spring is located inside the positioning sleeve and its front end face abuts against the inner wall of the front support portion, and its rear end face abuts against the front end face of the valve core.

[0020] The technical solution adopted by the present invention to solve the second technical problem mentioned above is: a dual-circulation gas water heater, comprising...

[0021] chassis;

[0022] The heat exchanger is located inside the aforementioned casing;

[0023] Heat exchange tubes are installed inside the aforementioned heat exchanger;

[0024] The water inlet pipe is connected to the water inlet end of the aforementioned heat exchange tube. The water inlet pipe is equipped with a flow meter, a water inlet temperature sensor, and a circulation pump.

[0025] The water outlet pipe is connected to the water outlet end of the aforementioned heat exchange tube, and the water outlet pipe is equipped with a water outlet temperature sensor.

[0026] An external hot water pipe, connected to the aforementioned water outlet pipe, is located outside the aforementioned casing;

[0027] An external return water pipe is connected between the aforementioned external hot water pipe and the inlet water pipe. The external return water pipe is equipped with a first one-way valve to ensure that water can only flow from the external hot water pipe to the inlet water pipe.

[0028] The control board is connected to the aforementioned flow meter, inlet water temperature sensor, circulating pump, and outlet water temperature sensor; and

[0029] The three-way solenoid switching valve has an inlet port connected to the outlet pipe, a first outlet port connected to the external hot water pipe, and a second outlet port connected to the inlet pipe via an internal return pipe. The internal return pipe is located inside the casing and is equipped with a second check valve to ensure that water can only flow from the internal return pipe to the inlet pipe. Furthermore, the three-way solenoid switching valve is connected to the control board.

[0030] Compared with the prior art, the advantages of the present invention are as follows:

[0031] The three-way solenoid switching valve is not energized. At this time, under the compression force of the spring, the entire valve core rests against the second valve port, which is closed, while the first valve port is open. Since the valve core is filled with water on both sides axially, there is no pressure difference, so the valve core is not affected by water pressure in the axial direction. Therefore, the spring force does not need to be large, and the first valve block is normally open, ensuring normal water use and external circulation functions. Water flows from the outlet pipe through the three-way solenoid switching valve into the external hot water pipe, and then into the external return water pipe. When the water circuit needs to switch from external circulation to internal circulation, the three-way solenoid switching valve is energized. The coil converts electrical energy into electromagnetic force, which acts on the valve stem, causing the valve stem to drive the valve core forward against the spring force. Since the spring force can be designed to be small, a low-power solenoid coil can meet the electromagnetic force design requirements, generating less heat and reducing cost. This continues until the valve core closes the first valve port, and simultaneously the second valve port opens, completing the internal circulation loop.

[0032] The three-way solenoid switching valve enables switching between internal and external circulation, and ensures that hot water is available on the first use, while the internal circulation ensures that there is no cold water when using water again.

[0033] Employing a dual-circulation system, the external circulation provides hot water upon initial use, while the internal circulation ensures no cold water is available for subsequent uses, resulting in greater energy efficiency and environmental friendliness. Combined with a three-way switching valve, it allows for two-position three-way water circuit switching, requiring minimal valve opening force and resolving the overheating issue of solenoid valves. The dual-circulation system boasts strong compatibility, low cost, and can be applied to existing zero-cold-water models for upgrades. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the structure of an embodiment.

[0035] Figure 2 This is an enlarged view of the external structure of the three-way solenoid switching valve in the embodiment.

[0036] Figure 3 This is a schematic diagram of the structure of a three-way solenoid switching valve (after removing the valve body and coil).

[0037] Figure 4 for Figure 3 The exploded diagram.

[0038] Figure 5 This is a schematic diagram of the three-way solenoid switching valve when the first valve port is open.

[0039] Figure 6 This is a schematic diagram showing the state of the three-way solenoid switching valve when the second valve port is open.

[0040] Figure 7 This is a control principle diagram for an example.

[0041] Figure 8 The diagram shows the temperature fluctuation of the reheated water in the example. Detailed Implementation

[0042] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0043] like Figure 1 As shown, the dual-circulation gas water heater in this embodiment includes a casing 1, a heat exchanger 2, a heat exchange tube 21, an inlet pipe 31, an outlet pipe 32, an external hot water pipe 33, an external return water pipe 34, a control board 10, a three-way solenoid switching valve 5, and an internal return water pipe 35.

[0044] Heat exchanger 2 is located inside casing 1, heat exchange tube 21 is located inside heat exchanger 2, water inlet pipe 31 is connected to the water inlet end of heat exchange tube 21, and water inlet pipe 31 is equipped with flow meter 311, water inlet temperature sensor 312 and circulation pump 313; water outlet pipe 32 is connected to the water outlet end of heat exchange tube 21, and water outlet pipe 32 is equipped with water outlet temperature sensor.

[0045] The external hot water pipe 33 is connected to the outlet pipe 32 and is located outside the casing 1; the external return water pipe 34 is connected between the external hot water pipe 33 and the inlet pipe 31, and the external return water pipe 34 is equipped with a first one-way valve 61 to ensure that water can only flow from the external hot water pipe 33 to the inlet pipe 31.

[0046] Combination Figure 7 As shown, the control board 10 is connected to the flow meter 311, the inlet water temperature sensor 312, the three-way solenoid switching valve 5, the circulating pump 313, and the outlet water temperature sensor 321.

[0047] The inlet port 511 of the three-way solenoid switching valve 5 is connected to the outlet pipe 32, the first outlet port 512 is connected to the external hot water pipe 33, and the second outlet port 513 is connected to the inlet pipe 31 through the inner return pipe 35. The inner return pipe 35 is arranged inside the housing 1 and is equipped with a second one-way valve 62 to ensure that water can only flow from the inner return pipe 35 to the inlet pipe 31.

[0048] like Figures 2-6 As shown, the three-way solenoid switching valve includes a valve body 51, a positioning sleeve 53, a valve core 54, a valve stem 52, a coil 55, and an isolation sleeve 56.

[0049] Valve body 51 has an inlet port, a first outlet port, a second outlet port, a first valve port, and a second valve port. The first valve port is connected to the first outlet port, and the second valve port is connected to the second outlet port. The inlet port can be connected to both the first and second valve ports.

[0050] The positioning sleeve 53 is disposed in the valve cavity of the valve body 51. In this embodiment, the positioning sleeve 53 is cylindrical and includes a front support portion 531, a rear support portion 532 and a connecting portion 533 located between the front support portion 531 and the rear support portion 532. The front support portion 531 and the rear support portion 532 are respectively formed with a front through hole 534 and a rear through hole 535 for the valve stem 52 to pass through. The spring 57 is located in the positioning sleeve 53 and its front end face abuts against the inner wall of the front support portion 531, and its rear end face abuts against the front end face of the valve core 54.

[0051] The valve stem 52 is axially movable in the valve cavity of the valve body 51 and its front end is restricted by the positioning sleeve 53; the valve core 54 is located in the middle of the valve stem 52 and can open and close the first valve port and the second valve port; the valve core 54 and the valve stem 52 are integrally injection molded.

[0052] The coil 55 is located at the rear end of the valve body 51 and has an inner cavity; the isolation sleeve 56 is located in the inner cavity of the coil 55 and has an axial cavity into which the rear end of the valve stem 52 extends; in this embodiment, the isolation sleeve 56 includes a main body 561 and an extension portion 562 that protrudes rearward from the main body 561. The main body 561 is sealed in the inner cavity of the valve body 51, and the extension portion 562 is located in the inner cavity of the coil 55.

[0053] Explanation of waterway switching principle:

[0054] 1. External circulation loop

[0055] Combination Figure 1 and Figure 5 As shown, in external circulation mode, the three-way solenoid switching valve is not energized. At this time, under the compression force of the spring, the entire valve core and sealing gasket press against the second valve port, which is closed, while the first valve port is open. Since the valve core is filled with water on both axial sides, there is no pressure difference, so the valve core is not affected by water pressure in the axial direction. Therefore, the spring force does not need to be large, and the first valve block is in the normally open state, ensuring normal water use and external circulation function. At this time, water flows from the outlet pipe through the three-way solenoid switching valve into the external hot water pipe, and then into the external return water pipe.

[0056] 2. Internal circulation loop

[0057] When the water circuit needs to switch from external circulation to internal circulation, the three-way solenoid switching valve is energized. The coil converts electrical energy into electromagnetic force, which acts on the valve stem, causing the valve stem to drive the valve core forward against the spring force. Since the spring force can be designed to be relatively small, a low-power solenoid coil can meet the design requirements for the electromagnetic force, resulting in less heat generation and lower cost. The water flows forward until the valve core closes the first valve port, while the second valve port opens, and the water flow direction is as follows: Figure 6 As shown, the inner loop is open.

[0058] A three-way switching valve and an internal circulation pipe are added to the unit, while the external circulation pipe is retained, forming a dual circulation system. In internal circulation mode, the unit uses a circulation pump to circulate and heat the water. Because the internal circulation pipe is short and located inside the unit, heat loss is negligible. Therefore, heating can be stopped once a certain temperature is reached, while the water continues to circulate, ensuring a completely uniform water temperature within the pipes (Tout = Tin = Tset). During ignition, the unit first removes hot water from the inlet and heat exchanger pipes before adding cold water. Based on the total volume of the heat exchanger coil and inlet pipe of a 16L gas water heater being 0.25L, and assuming a typical user water flow rate of 7L / min, cold water will be added after 2.14 seconds. During this time, the unit has already completed the ignition process and is in heating mode, completely avoiding the window period that would create intercalary cold water. Therefore, theoretically, there will be almost no temperature fluctuation after the user turns the water off and on again, and this has been verified through time-based experiments. Figure 8 As shown, the temperature fluctuation of the reheated water can be controlled within 2℃, with a significant effect. Furthermore, the internal circulation pipe is short, and the circulation cycle can be controlled within 10 seconds, greatly reducing gas energy consumption.

[0059] In summary, the external circulation system can meet the needs of initial hot water boiling and hot water production, while the internal circulation system can solve the problem of cold water in the interlayer when boiling water again and can greatly reduce energy consumption. The combination of internal and external circulation can truly achieve zero cold water.

[0060] Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions. In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Since the embodiments disclosed in this invention can be arranged in different directions, these terms indicating direction are only illustrative and should not be regarded as limitations. For example, "upper" and "lower" are not necessarily limited to directions opposite to or consistent with the direction of gravity. Furthermore, features defined with "first" and "second" may explicitly or implicitly include one or more of that feature.

Claims

1. A three-way solenoid switching valve, characterized in that... include The valve body (51) has an inlet port, a first outlet port, a second outlet port, a first valve port, and a second valve port. The first valve port is connected to the first outlet port, and the second valve port is connected to the second outlet port. The inlet port can be connected to the first valve port and the second valve port. A positioning sleeve (53) is provided inside the valve cavity of the aforementioned valve body (51); The valve stem (52) is axially movable in the valve cavity of the aforementioned valve body (51) and its front end is restricted by the aforementioned positioning sleeve (53); The valve core (54) is located in the middle of the aforementioned valve stem (52) and can open and close the first valve port and the second valve port; A coil (55) is located at the rear end of the aforementioned valve body (51) and has an inner cavity; An isolation sleeve (56) is provided within the cavity of the aforementioned coil (55) and has an axial cavity into which the rear end of the valve stem (52) extends; and A spring (57) is provided inside the aforementioned positioning sleeve (53) and acts on the valve stem (52); When the coil (55) is not energized, the valve core (54) is moved backward by the action of the spring (57), and the valve core (54) closes the second valve port and opens the first valve port at the same time; at this time, the axial through hole on the valve core connects the valve chambers on both sides of the valve core in the axial direction, and the two sides of the valve core in the axial direction are filled with water, and there is no pressure difference; When the coil (55) is energized, the valve stem (52) is acted upon by the magnetic field force of the coil (55) and drives the valve core (54) to move forward. The valve core (54) closes the first valve port and opens the second valve port. The positioning sleeve (53) is cylindrical and includes a front support part (531), a rear support part (532) and a connecting part (533) located between the front support part (531) and the rear support part (532). The front support part (531) and the rear support part (532) are respectively formed with a front through hole (534) and a rear through hole (535) for the valve stem (52) to pass through. The spring (57) is located inside the positioning sleeve (53) and its front end face abuts against the inner wall of the front support part (531), and its rear end face abuts against the front end face of the valve core (54).

2. The three-way solenoid switching valve according to claim 1, characterized in that... The isolation sleeve (56) includes a main body (561) and an extension (562) protruding rearward from the main body (561). The main body (561) is sealed in the inner cavity of the valve body (51), and the extension (562) is disposed in the inner cavity of the coil (55).

3. The three-way solenoid switching valve according to claim 1, characterized in that... The valve core (54) and valve stem (52) are integrally injection molded.

4. A dual-circulation gas water heater having a three-way electromagnetic switching valve as described in any one of claims 1 to 3, characterized in that... include Casing (1); Heat exchanger (2) is located inside the aforementioned housing (1); Heat exchange tube (21) is installed inside the aforementioned heat exchanger (2); The water inlet pipe (31) is connected to the water inlet end of the aforementioned heat exchange pipe (21). The water inlet pipe (31) is equipped with a flow meter (311), a water inlet temperature sensor (312), and a circulation pump (313). The water outlet pipe (32) is connected to the water outlet end of the aforementioned heat exchange pipe (21), and the water outlet pipe (32) is equipped with a water outlet temperature sensor; An external hot water pipe (33) is connected to the aforementioned water outlet pipe (32) and is located outside the aforementioned housing (1); An external return water pipe (34) is connected between the aforementioned external hot water pipe (33) and the inlet water pipe (31). The external return water pipe (34) is equipped with a first one-way valve (61) to ensure that water can only flow from the external hot water pipe (33) to the inlet water pipe (31). The control board (10) is connected to the aforementioned flow meter (311), inlet water temperature sensor (312), circulating pump, and outlet water temperature sensor; and The three-way solenoid switching valve (5) has an inlet port (511) connected to an outlet pipe (32), a first outlet port (512) connected to an external hot water pipe (33), and a second outlet port (513) connected to an inlet pipe (31) via an inner return pipe (35). The inner return pipe (35) is arranged inside the casing (1) and is equipped with a second one-way valve (62) to ensure that water can only flow from the inner return pipe (35) to the inlet pipe (31). The three-way solenoid switching valve (5) is connected to the control board (10).

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