Heat exchanger and water heater

Abstract

This utility model belongs to the field of water heater technology, and discloses a heat exchanger and a water heater. A thermistor is located inside the hot water outlet pipe, which can promptly sense changes in the water temperature within the outlet pipe. This allows the thermistor to adjust the connection between the bypass pipe and the hot water outlet pipe based on thermal expansion and contraction. Since the connection between the bypass pipe and the hot water outlet pipe is directly proportional to the temperature of the hot water flowing through the thermistor in the outlet pipe, the lower the water temperature, the greater the expansion of the thermistor, and the smaller the connection between the hot water outlet pipe and the bypass pipe. This is beneficial because when the temperature in the hot water outlet pipe is low, reducing the connection between the bypass pipe and the hot water outlet pipe decreases the amount of cold water entering the outlet pipe through the bypass pipe, thereby increasing the amount of cold water entering the main heat exchanger through the cold water inlet pipe and improving the heat exchanger's heat exchange efficiency. This heat exchanger can achieve autonomous adjustment of the bypass ratio, not only solving the problem of temperature rise during water outages but also ensuring the heat exchanger's performance.

Description

Technical Field

[0001] This utility model relates to the field of water heater technology, and in particular to a heat exchanger and a water heater. Background Technology

[0002] As is well known, existing gas water heaters have a problem with temperature rise during water outages. Specifically, when water usage stops, residual heat continues to heat the water in the main heat exchanger, causing the water in the main heat exchanger to rise in temperature. When water is used again, the water flowing out initially may be higher than the user's set temperature, potentially scalding the user.

[0003] To solve the above technical problems, a bypass pipe is generally added to connect the cold water inlet pipe and the hot water outlet pipe. When restarting, some of the cold water in the cold water inlet pipe enters the hot water outlet pipe through the bypass pipe. The cold water entering the hot water outlet pipe mixes with the hot water sent to the hot water outlet pipe by the main heat exchanger before being discharged. This can effectively avoid the problem of the water being too hot when it first flows out.

[0004] However, when a user uses hot water, if the temperature of the hot water entering the hot water outlet pipe after heat exchange is lower than the user's set temperature, some of the cold water supplied by the cold water inlet pipe will still enter the hot water outlet pipe through the bypass pipe. With the amount of cold water entering the cold water inlet pipe remaining constant, if the hot water outlet temperature is lower than the user's required temperature, the small amount of cold water entering the hot water outlet pipe through the bypass pipe will reduce the amount of cold water supplied to the heat exchanger. This reduces the amount of heat energy that the cold water supplied to the heat exchanger can absorb, thereby reducing the heat exchanger's heat exchange efficiency. Utility Model Content

[0005] One of the technical problems solved by this utility model is to provide a heat exchanger that can improve the heat exchange efficiency of the heat exchanger.

[0006] The second technical problem solved by this utility model is to provide a water heater that can improve the heat exchange efficiency of the water heater.

[0007] The first technical problem mentioned above is solved by the following technical solution:

[0008] A heat exchanger includes a main heat exchanger having a cold water inlet and a hot water outlet, a cold water inlet pipe connected to the cold water inlet, a hot water outlet pipe connected to the hot water outlet, and a bypass pipe having one end connected to the cold water inlet pipe and the other end connected to the hot water outlet pipe. The heat exchanger also includes a thermistor located inside the hot water outlet pipe, and the thermistor is connected to the bypass pipe or the hot water outlet pipe.

[0009] The thermistor can expand and contract with the temperature of the hot water flowing through it in the hot water outlet pipe, thereby adjusting the connection between the bypass pipe and the hot water outlet pipe. The connection between the bypass pipe and the hot water outlet pipe is directly proportional to the temperature of the hot water flowing through it in the hot water outlet pipe.

[0010] The heat exchanger described in this utility model has the following advantages compared with the prior art:

[0011] Because the thermistor is located inside the hot water outlet pipe, it can promptly sense changes in the water temperature within the pipe. This allows the thermistor to adjust the connection between the bypass pipe and the hot water outlet pipe based on thermal expansion and contraction. Since the connection between the bypass pipe and the hot water outlet pipe is directly proportional to the temperature of the hot water flowing through the thermistor, the lower the water temperature, the greater the expansion of the thermistor and the smaller the connection between the hot water outlet pipe and the bypass pipe. This reduces the amount of cold water entering the hot water outlet pipe through the bypass pipe when the temperature is low, thus increasing the amount of cold water entering the main heat exchanger from the cold water inlet pipe. This improves heat absorption and the heat exchanger's efficiency. This heat exchanger can autonomously adjust the bypass ratio, not only solving the problem of temperature rise during water outages but also ensuring the heat exchanger's performance.

[0012] In one embodiment, the thermistor is provided with a water passage hole, and the bypass pipe can be connected to the hot water outlet pipe through the water passage hole; the water passage hole can be selectively opened and closed according to the temperature of the hot water flowing through the thermistor.

[0013] In one embodiment, the thermal element includes an outer peripheral portion and a central portion, the outer peripheral portion being spaced out from the central portion, and the outer peripheral portion and the central portion being connected by a plurality of connecting ribs arranged circumferentially spaced from the central portion.

[0014] The water passage includes a first water passage, which is formed between two adjacent connecting ribs.

[0015] In one embodiment, the thermistor is connected to the bypass pipe, and when the thermistor connects the bypass pipe and the hot water outlet pipe, the end of the thermistor away from the bypass pipe is spaced apart from the inner wall of the hot water outlet pipe.

[0016] In one embodiment, the water passage further includes:

[0017] The second water passage has one end extending to the inner peripheral wall of the outer peripheral portion and the other end extending to the outer peripheral wall of the outer peripheral portion. Each of the first water passages is connected to the hot water outlet pipe through at least one second water passage.

[0018] In one embodiment, the water passage further includes a third water passage disposed on the central portion, the two ends of the third water passage being connected to different first water passages.

[0019] In one embodiment, the second and third water passages, which are connected to the same first water passage, are arranged coaxially.

[0020] In one embodiment, the thermal element is a one-piece molded structure.

[0021] In one embodiment, the thermal element and the bypass conduit are interference-fitted, threaded, or bonded together.

[0022] The second technical problem mentioned above is solved by the following technical solution:

[0023] A water heater includes a housing, a burner disposed within the housing, and a heat exchanger as provided in any of the above embodiments, wherein the burner is capable of burning gas to heat the heat exchanger.

[0024] Compared with the prior art, the water heater described in this utility model has the following beneficial effects:

[0025] The water heater provided by this utility model includes the aforementioned heat exchanger. Since the thermistor is located inside the hot water outlet pipe, it can promptly sense changes in the water temperature within the outlet pipe. This allows the thermistor to adjust the connection between the bypass pipe and the hot water outlet pipe based on thermal expansion and contraction. Because the connection between the bypass pipe and the hot water outlet pipe is directly proportional to the temperature of the hot water flowing through the thermistor in the outlet pipe, the lower the water temperature, the greater the expansion of the thermistor and the smaller the connection between the hot water outlet pipe and the bypass pipe. This is beneficial because when the temperature in the hot water outlet pipe is low, reducing the connection between the bypass pipe and the hot water outlet pipe decreases the amount of cold water entering the outlet pipe through the bypass pipe. Consequently, the amount of cold water entering the main heat exchanger from the cold water inlet pipe increases, improving heat absorption and the heat exchanger's efficiency, thereby enhancing the overall heat exchange efficiency of the water heater. This heat exchanger can autonomously adjust the bypass ratio, not only solving the problem of temperature rise during water outages but also ensuring the heat exchanger's performance. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the heat exchanger provided in this embodiment of the utility model;

[0027] Figure 2 yes Figure 1 Enlarged layout diagram at point A in the diagram;

[0028] Figure 3This is a schematic diagram of the structure of the thermistor provided in an embodiment of the present invention;

[0029] Figure 4 This is an axial schematic diagram of the thermal element provided in an embodiment of the present invention.

[0030] In the picture:

[0031] 1. Main heat exchanger; 2. Cold water inlet pipe; 3. Hot water outlet pipe; 4. Bypass pipe; 5. Thermistor; 51. Central part; 511. Third water passage hole; 52. Outer periphery; 521. Second water passage hole; 53. Connecting rib; 54. First water passage hole. Detailed Implementation

[0032] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0033] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application 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. Therefore, they should not be construed as limitations on this application.

[0034] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0035] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0036] The present invention provides a heat exchanger and a water heater including the heat exchanger, which can improve the heat exchange efficiency of the heat exchanger.

[0037] like Figure 1 and Figure 2 As shown, the heat exchanger includes a main heat exchanger 1 with a cold water inlet and a hot water outlet, a cold water inlet pipe 2 connected to the cold water inlet, a hot water outlet pipe 3 connected to the hot water outlet, and a bypass pipe 4 with one end connected to the cold water inlet pipe 2 and the other end connected to the hot water outlet pipe 3. The heat exchanger also includes a thermistor 5 located inside the hot water outlet pipe 3, and the thermistor 5 is connected to the bypass pipe 4. Exemplarily, the thermistor 5 is a structural component made of a thermally expanding material.

[0038] The thermal element 5 can expand and contract with the temperature change of the hot water flowing through the thermal element 5 in the hot water outlet pipe 3, so as to adjust the connection opening between the bypass pipe 4 and the hot water outlet pipe 3. The connection opening between the bypass pipe 4 and the hot water outlet pipe 3 is directly proportional to the temperature of the hot water flowing through the thermal element 5 in the hot water outlet pipe 3.

[0039] Since the thermistor 5 is located inside the hot water outlet pipe 3, it can promptly sense changes in the water temperature within the pipe. This allows the thermistor 5 to expand and contract with temperature changes, altering the connection between the bypass pipe 4 and the hot water outlet pipe 3. Because the connection between the bypass pipe 4 and the hot water outlet pipe 3 is directly proportional to the temperature of the hot water flowing through the thermistor 5 within the pipe, the lower the water temperature in the pipe, the greater the expansion of the thermistor 5, and the smaller the connection between the hot water outlet pipe 3 and the bypass pipe 4. This is beneficial when the temperature in the hot water outlet pipe 3 is low, by reducing the connection between the bypass pipe 4 and the hot water outlet pipe 3, thereby reducing the amount of cold water entering the pipe through the bypass pipe 4. Consequently, this increases the amount of cold water entering the main heat exchanger 1 from the cold water inlet pipe 2, increasing heat absorption and the heat exchange efficiency of the heat exchanger, thus improving the overall heat exchange efficiency of the water heater.

[0040] After the user stops using hot water, the water flowing in the main heat exchanger 1 continues to absorb residual heat, causing the water temperature in the main heat exchanger 1 to rise. When the user uses water again in a short period of time, the temperature of the hot water pipe 3 sent from the main heat exchanger 1 is relatively high, and the temperature of the hot water flowing through the thermistor 5 is also relatively high. This puts the thermistor 5 in a high-temperature environment, resulting in a small amount of thermal expansion deformation. The opening of the bypass pipe 4 and the hot water pipe 3 is relatively large, allowing the cold water inlet pipe 2 to send more cold water through the bypass pipe 4 into the hot water pipe 3. The cold water and the hot water in the hot water pipe 3 are mixed and then sent to the user, which can prevent the phenomenon of temperature rise during water outage.

[0041] This heat exchanger can autonomously adjust the bypass ratio, which not only solves the problem of temperature rise during water outages but also ensures the heat exchange performance of the heat exchanger.

[0042] For example, when the water temperature flowing through the thermistor 5 exceeds 60°C, the volume of the thermistor 5 shrinks, increasing the opening between the bypass pipe 4 and the hot water outlet pipe 3. The bypass pipe 4 then delivers more cold water into the hot water outlet pipe 3 to address the issue of temperature rise during water outages. When the water temperature flowing through the thermistor 5 is below 60°C, the volume of the thermistor 5 expands, decreasing the opening between the bypass pipe 4 and the hot water outlet pipe 3. This reduces the amount of cold water delivered into the hot water outlet pipe 3 via the bypass pipe 4, thereby increasing the amount of cold water delivered into the main heat exchanger 1 via the cold water inlet pipe 2 and improving the heat exchange efficiency of the main heat exchanger 1.

[0043] In some embodiments, such as Figures 2 to 4 As shown, the thermistor 5 is provided with a water passage hole, and the bypass pipe 4 can be connected to the hot water outlet pipe 3 through the water passage hole; the water passage hole can be selectively opened and closed according to the temperature of the hot water flowing through the thermistor 5.

[0044] When the temperature of the hot water flowing through the thermistor 5 is low, the thermistor 5 expands, increasing its volume. When the water passage is broken due to the expansion and deformation of the thermistor 5, all the cold water in the cold water inlet pipe 2 enters the main heat exchanger 1. When the temperature of the hot water flowing through the thermistor 5 is high, the thermistor 5 contracts, reducing the opening between the bypass pipe 4 and the hot water outlet pipe 3. Some of the cold water in the cold water inlet pipe 2 enters the hot water outlet pipe 3 through the bypass pipe 4, while the other part of the cold water enters the main heat exchanger 1.

[0045] In some embodiments, such as Figures 2 to 4 As shown, the thermal element 5 includes an outer peripheral portion 52 and a central portion 51. The outer peripheral portion 52 is spaced outside the central portion 51. The outer peripheral portion 52 and the central portion 51 are connected by a plurality of connecting ribs 53 arranged circumferentially around the central portion 51. The water passage includes a first water passage 54, and a first water passage 54 is formed between two adjacent connecting ribs 53.

[0046] For example, four first water passage holes 54 are provided, and the four first water passage holes 54 are arranged at equal intervals around the periphery of the thermal element 5, and the first water passage holes 54 are arranged through the axial direction of the thermal element 5.

[0047] For example, the connecting rib 53 has a uniform thickness structure. Correspondingly, the first water passage hole 54 has a fan-shaped cross section perpendicular to the axis of the thermal element 5. This arrangement can maximize the cross-sectional area of ​​the first water passage hole 54. When the hot water flowing through the thermal element 5 in the hot water outlet pipe 3 has a high temperature, the cold water in the bypass pipe 4 can enter the hot water outlet pipe 3 in a timely manner.

[0048] When the hot water flowing in the hot water outlet pipe 3 is at a high temperature, the bypass pipe 4 connects the hot water outlet pipe 3 and the bypass pipe 4. The cold water in the bypass pipe 4 enters the hot water outlet pipe 3 through multiple first water passage holes 54.

[0049] In some embodiments, such as Figures 2 to 4 As shown, the thermal element 5 is connected to the bypass pipe 4. When the thermal element 5 connects the bypass pipe 4 and the hot water outlet pipe 3, the end of the thermal element 5 away from the bypass pipe 4 is spaced apart from the inner wall of the hot water outlet pipe 3. This arrangement ensures that when the hot water flowing through the thermal element 5 is at a high temperature, the end of the first water passage 54 away from the bypass pipe 4 will not reduce the opening of the bypass pipe 4 due to contact with the inner wall of the hot water outlet pipe 3.

[0050] In some embodiments, such as Figures 2 to 4 As shown, the water passage hole also includes a second water passage hole 521. One end of the second water passage hole 521 extends to the inner peripheral wall of the outer peripheral portion 52, and the other end extends to the outer peripheral wall of the outer peripheral portion 52. Each first water passage hole 54 is connected to the hot water outlet pipe 3 through at least one second water passage hole 521.

[0051] This configuration allows hot water in the hot water outlet pipe 3 to enter the corresponding first water outlet pipe 54 through the second water passage 521, resulting in a larger contact area between the thermal element 5 and the hot water. This facilitates the thermal element 5 in timely sensing of temperature changes in the hot water outlet pipe 3 and adjusting the connection between the bypass pipe 4 and the hot water outlet pipe 3 based on the water temperature in the hot water outlet pipe 3.

[0052] For example, each first water passage 54 is provided with a second water passage 521. It should be noted that the number of second water passages 521 provided with each first water passage 54 can also be two, three or more, etc.

[0053] In some embodiments, such as Figures 2 to 4 As shown, the water passage also includes a third water passage 511 provided on the central part 51, and the two ends of the third water passage 511 are connected to different first water passages 54.

[0054] Hot water flowing in the hot water outlet pipe 3 can enter the first water outlet 54 through the second water outlet 521. Hot water in one first water outlet 54 can enter another first water outlet 54 through the third water outlet 511, further increasing the contact area between the hot water and the thermal element 5. This makes it easier for the thermal element 5 to sense the temperature change in the hot water outlet pipe 3 in a timely manner and to expand and contract according to the water temperature in the hot water outlet pipe 3 to adjust the connection opening between the bypass pipe 4 and the hot water outlet pipe 3.

[0055] In some embodiments, such as Figures 2 to 4As shown, there are an even number of first water passage holes 54, and two first water passage holes 54 arranged at 180° are connected through at least one third water passage hole 511. This ensures that any pair of first water passage holes 54 arranged at 180° can be connected through at least one third water passage hole 511. For example, there are four first water passage holes 54 and two second water passage holes 521, and the central axes of the two second water passage holes 521 form a cross shape in a cross section perpendicular to the axis of the thermal element 5.

[0056] In some embodiments, the second water passage 521 and the third water passage 511, which communicate with the same first water passage 54, are arranged coaxially. This arrangement facilitates the machining of the second water passage 521 and the third water passage 511.

[0057] In some embodiments, the thermistor 5 is a one-piece molded structure. This configuration simplifies the manufacturing process of the thermistor 5, reduces its manufacturing cost, and improves its manufacturing efficiency.

[0058] In some embodiments, such as Figures 2 to 4 As shown, the thermal element 5 is glued and fixed to the bypass pipe 4. The connection between the thermal element 5 and the bypass pipe 4 is simple, low-cost, and highly efficient. In other embodiments, the thermal element 5 can also be installed in the bypass pipe 4 with an interference fit. However, since the thermal element 5 will expand and contract according to the temperature changes of the water in the bypass pipe 4, and the higher the water temperature flowing through the thermal element 5, the larger the opening between the bypass pipe 4 and the hot water outlet pipe 3, in order to avoid the connection between the thermal element 5 and the bypass pipe 4 failing due to the high water temperature flowing through the thermal element 5 in the hot water outlet pipe 3, the thermal element 5 is installed in the bypass pipe 4 with an interference fit when there is no deformation or very little deformation. In some other embodiments, the thermal element 5 can also be threaded to the bypass pipe 4.

[0059] In other embodiments, the thermistor 5 can also be connected to the hot water outlet pipe 3. The thermistor 5 can be deformed by thermal expansion and contraction according to the temperature change of the hot water flowing through it, so as to change the connection opening between the bypass pipe 4 and the hot water outlet pipe 3.

[0060] In some embodiments, the present invention also provides a water heater, including a housing, a burner disposed within the housing, and the aforementioned heat exchanger, wherein the burner is capable of burning gas to heat the heat exchanger. Specifically, the high-temperature flue gas generated by the burner burning gas flows through the heat exchanger, causing cold water flowing through the heat exchanger to absorb the heat energy from the high-temperature flue gas.

[0061] In the specific implementation of the above embodiments, the technical features can be combined in any non-contradictory way. For the sake of brevity, not all possible combinations of the above technical features are described. However, as long as the combination of these technical features is not contradictory, it should be considered to be within the scope of this specification.

[0062] The specific embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A heat exchanger, comprising a main heat exchanger (1) having a cold water inlet and a hot water outlet, a cold water inlet pipe (2) connected to the cold water inlet, a hot water outlet pipe (3) connected to the hot water outlet, and a bypass pipe (4) having one end connected to the cold water inlet pipe (2) and the other end connected to the hot water outlet pipe (3), characterized in that, The heat exchanger also includes a thermistor (5) located in the hot water outlet pipe (3), and the thermistor (5) is connected to the bypass pipe (4) or the hot water outlet pipe (3); The thermal element (5) can expand and contract with the temperature of the hot water flowing through the thermal element (5) in the hot water outlet pipe (3) to adjust the connection between the bypass pipe (4) and the hot water outlet pipe (3). The connection between the bypass pipe (4) and the hot water outlet pipe (3) is directly proportional to the temperature of the hot water flowing through the thermal element (5) in the hot water outlet pipe (3).

2. The heat exchanger according to claim 1, characterized in that, The thermal element (5) is provided with a water passage hole, and the bypass pipe (4) can be connected to the hot water outlet pipe (3) through the water passage hole; the water passage hole can be selectively opened and closed according to the temperature of the hot water flowing through the thermal element (5).

3. The heat exchanger according to claim 2, characterized in that, The thermal element (5) includes an outer peripheral portion (52) and a central portion (51). The outer peripheral portion (52) is spaced outside the central portion (51). The outer peripheral portion (52) and the central portion (51) are connected by a plurality of connecting ribs (53) arranged circumferentially around the central portion (51). The water passage includes a first water passage (54), and a first water passage (54) is formed between two adjacent connecting ribs (53).

4. The heat exchanger according to claim 3, characterized in that, The thermal element (5) is connected to the bypass pipe (4). When the thermal element (5) connects the bypass pipe (4) and the hot water outlet pipe (3), the end of the thermal element (5) away from the bypass pipe (4) is spaced apart from the inner wall of the hot water outlet pipe (3).

5. The heat exchanger according to claim 3, characterized in that, The water passage also includes: The second water passage (521) has one end extending to the inner peripheral wall of the outer peripheral portion (52) and the other end extending to the outer peripheral wall of the outer peripheral portion (52). Each of the first water passages (54) is connected to the hot water outlet pipe (3) through at least one of the second water passages (521).

6. The heat exchanger according to claim 5, characterized in that, The water passage also includes a third water passage (511) disposed on the central part (51), the two ends of the third water passage (511) being connected to different first water passages (54).

7. The heat exchanger according to claim 6, characterized in that, The second water passage (521) and the third water passage (511), which are connected to the same first water passage (54), are arranged coaxially.

8. The heat exchanger according to any one of claims 1 to 7, characterized in that, The thermal element (5) is a one-piece molded structure.

9. The heat exchanger according to any one of claims 1 to 7, characterized in that, The thermal element (5) and the bypass pipe (4) are interference-fitted, threaded, or glued together.

10. A water heater, characterized in that, The device includes a housing, a burner disposed within the housing, and a heat exchanger as claimed in any one of claims 1 to 9, wherein the burner is capable of burning fuel gas to heat the heat exchanger.

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