Blow-down valve and water heater
By integrating the sealing gasket and valve integral, the problems of complex assembly and low reliability of waste sewage valves are solved, tighter sealing connections and higher reliability are achieved, while simplifying the production process.
Patent Information
- Application Number
- CN202420782885.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-16
- Publication Date
- 2025-03-21
- Estimated Expiration
- 2034-04-16
AI Technical Summary
The existing sewage valves are complex in assembly and have low reliability after assembly.
By integrating the first and second gaskets with the valve body, the number of parts is reduced, the manufacturing and assembly process is simplified, and the stability of the gasket is improved through joint inserts and limit slots.
Reduces the risk of loose or misalignment of the seal, ensures a tighter connection between the seal and the valve body, improves the reliability of the drain valve, and reduces production costs.
Smart Images
Figure CN222650611U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of sewage valves, in particular to a sewage valve and a water heater. Background Art
[0002] A blowdown valve is a valve used to control the discharge or release of pressure, gas or liquid in a fluid system.
[0003] The sewage valve generally includes a valve body, a valve cover, a valve ball, a valve stem, an operating handle, a sealing member, a connector, etc. However, the existing sewage valve is complicated to assemble and has low reliability after assembly.
[0004] Therefore, the existing drain valve has room for improvement. Utility Model Content
[0005] The utility model provides a drain valve and a water heater, which are used to solve the defects of the existing drain valve, that is, the drain valve is complicated to assemble and has low reliability after assembly, thereby reducing the difficulty of assembling the drain valve and improving the reliability of the drain valve.
[0006] The utility model provides a sewage valve, comprising:
[0007] A valve body, wherein a valve cavity, a first flow channel and a second flow channel are formed in the valve body, and the first flow channel and the second flow channel are both connected to the valve cavity;
[0008] a valve ball, the valve ball being disposed in the valve cavity;
[0009] a valve shaft connected to the valve ball;
[0010] a first sealing gasket, the first sealing gasket being disposed in the valve body and being used for sealingly cooperating with the valve ball to close the first flow channel;
[0011] a second sealing gasket, the second sealing gasket being disposed in the valve body, and the second sealing gasket being used for sealingly cooperating with the valve ball to close the second flow channel;
[0012] The first sealing gasket and the second sealing gasket are both integrated with the valve body.
[0013] The sewage valve provided by the utility model further includes a joint inlay, one end of which is arranged in the first flow channel, and the joint inlay is integrated with the valve body.
[0014] According to the sewage valve provided by the utility model, a limit groove is provided on the joint inlay, and the first sealing gasket is arranged in the limit groove and seals with the limit groove.
[0015] According to the sewage valve provided by the utility model, the valve shaft and the valve ball are integrated.
[0016] According to the sewage drain valve provided by the utility model, a sealing ring is provided between the valve shaft and the valve body.
[0017] The sewage valve provided by the utility model further comprises a check ring for limiting the position of the sealing ring, and the check ring is arranged on the outside of the sealing ring.
[0018] The sewage valve provided by the utility model further includes a valve cover and a handle, wherein the valve cover is connected to the valve shaft, and the handle includes a fixed section and a folding section, wherein the fixed section is connected to the valve cover, and the folding section is hinged to the fixed section.
[0019] According to the sewage valve provided by the utility model, in the folded state, the folded section is located at one side of the valve body.
[0020] The sewage drain valve provided by the utility model further comprises a flexible joint, and the flexible joint is rotatably connected to the valve body.
[0021] Another aspect of the utility model provides a water heater, comprising the sewage valve as described in any one of the above items.
[0022] The sewage valve provided by the utility model can reduce the risk of the sealing gasket loosening or dislocation by integrating the first sealing gasket and the second sealing gasket with the valve body, ensure a tighter connection between the sealing gasket and the valve body, improve the stability of the sealing gasket, and thus improve the reliability of the sewage valve. In addition, it can also reduce the number of parts, simplify the manufacturing and assembly process, and reduce production costs.
[0023] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0025] Figure 1 It is a schematic diagram of a sewage valve provided in an embodiment of the utility model;
[0026] Figure 2 It is a cross-sectional view of a sewage valve provided by an embodiment of the utility model;
[0027] Figure 3It is a schematic diagram of the handle of the sewage valve provided by the embodiment of the utility model when it is unfolded;
[0028] Figure 4 It is a schematic diagram of a handle of a sewage valve provided by an embodiment of the utility model when it is folded.
[0029] Reference numerals:
[0030] 1. Valve body; 2. Valve ball; 3. Valve shaft; 4. First sealing gasket; 5. Second sealing gasket; 6. Joint inlay; 7. Sealing ring; 8. Check ring; 9. Valve cover; 10. Handle; 10a. Fixed section; 10b. Folding section; 11. Flexible joint; 12. Magnesium rod bracket. DETAILED DESCRIPTION
[0031] In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be described clearly and completely in conjunction with the drawings in the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0032] In the description of the embodiments of the present utility model, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present utility model. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.
[0033] In the description of the embodiments of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.
[0034] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0035] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model embodiment. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.
[0036] Combine the following Figures 1 to 4 The utility model is described as a sewage valve and a water heater.
[0037] It should be noted that, in order to distinguish and illustrate the valve body 1, the first sealing gasket 4, the second sealing gasket 5 and the joint inlay 6, Figure 2 The outlines of the above components are shown schematically in FIG.
[0038] See also Figure 1 and Figure 2 As shown, the sewage valve provided by the embodiment of the utility model includes a valve body 1, a valve ball 2, a valve shaft 3, a first sealing gasket 4 and a second sealing gasket 5. Among them, a valve cavity, a first flow channel and a second flow channel are formed in the valve body 1, the first flow channel and the second flow channel are both connected to the valve cavity, the valve ball 2 is arranged in the valve cavity, the valve shaft 3 is connected to the valve ball 2, the first sealing gasket 4 is arranged in the valve body 1, the first sealing gasket 4 is used to seal with the valve ball 2 to close the first flow channel, the second sealing gasket 5 is arranged in the valve body 1, the second sealing gasket 4 is used to seal with the valve ball 2 to close the second flow channel; the first sealing gasket 4 and the second sealing gasket 5 are both integrated with the valve body 1.
[0039] The sewage valve provided by the utility model can reduce the risk of the sealing gasket loosening or misalignment by integrating the first sealing gasket 4 and the second sealing gasket 5 with the valve body 1, ensure a tighter connection between the sealing gasket and the valve body 1, improve the stability of the sealing gasket, and thus improve the reliability of the sewage valve. In addition, it can also reduce the number of parts, simplify the manufacturing and assembly process, and reduce production costs.
[0040] Specifically, during processing, the first sealing gasket 4, the second sealing gasket 5 and the remaining required components (such as the joint insert 6 described below) can be first placed in the corresponding mold, and the raw material used to form the valve body 1 is placed in the hopper of the injection molding machine and melted by heating. When the raw material reaches the set temperature and fluidity, the molten plastic is injected into the mold through the nozzle of the injection molding machine. The cavity and structure inside the mold enable the molten plastic to form the desired part shape. In this process, the material of the valve body 1 can be interconnected with the first sealing gasket 4, the second sealing gasket 5 and the remaining required components pre-set in the mold to form a whole, ensuring a tighter connection between the sealing gasket and the valve body 1, improving the stability of the sealing gasket, and thus improving the reliability of the sewage valve.
[0041] The valve body 1 can be made of materials such as PP (polypropylene), PVC (polyvinyl chloride), CPVC (polypropylene acrylonitrile), PTFE (polytetrafluoroethylene) or PA (polyamide, nylon). Among them, polypropylene material has good corrosion resistance and mechanical properties; polyvinyl chloride has good corrosion resistance and cost-effectiveness, and is suitable for working under low pressure and general temperature conditions in water heaters; polypropylene acrylonitrile is a modified polyvinyl chloride, which has better heat resistance and corrosion resistance than polyvinyl chloride; polytetrafluoroethylene has excellent corrosion resistance and high temperature resistance; polyamide has good wear resistance and mechanical properties. The above materials can provide reliable performance under specific working conditions. In specific implementation, they can be selected according to the use conditions of the drain valve.
[0042] It should be noted that see Figure 2 As shown, in this embodiment, the first flow channel is used to connect with the water heater body, and the second flow channel is used to connect with the sewage pipe. In the non-sewage discharge state, the first sealing gasket 4 and the second sealing gasket 5 are respectively in contact with the valve ball 2 and sealed with the valve ball 2, and the first flow channel and the second flow channel are in a disconnected state. When discharging sewage, the sewage valve can be opened, and the two ends of the flow channel of the valve ball 2 are respectively connected with the first flow channel and the second flow channel, so that the sewage and sediment accumulated inside the water heater can be discharged.
[0043] See also Figure 2As shown, according to some embodiments of the utility model, one end of the valve shaft 3 extends out of the valve cavity to drive the valve ball 2 to rotate, and control whether the flow passage of the valve ball 2 is connected with the first flow passage and the second flow passage. The end of the valve shaft 3 is connected to the valve cover 9, and the valve shaft 3 is provided with a threaded hole. The valve cover 9 is connected to the valve shaft 3 by screws, and the valve shaft 3 can be driven to rotate by driving the valve cover 9. The valve cover 9 is provided with a handle 10, which is convenient for applying a driving action to the valve cover 9 through the handle 10.
[0044] See also Figure 2 As shown, according to some embodiments of the utility model, the drain valve further includes a joint insert 6, one end of which is disposed in the first flow channel, and the joint insert 6 is integrated with the valve body 1. By integrating the joint insert 6 with the valve body 1, the number of connections between parts can be reduced, reducing potential water leakage points and failure risks, thereby enhancing the overall structural strength of the valve body 1, making it more durable and stable. In addition, as described above, the joint insert 6 can be connected to the valve body 1 as a whole in the same process as the first sealing gasket 4 and the second sealing gasket 5, without the need to set up additional processes for assembly and fixation.
[0045] It should be noted that the joint insert 6 refers to a component that connects the drain valve and the pipeline system. It can be made of metal or plastic and has an interface that matches the pipeline system to ensure that the connection between the drain valve and the pipeline is tight and sealed. The joint insert 6 plays a role of connection and fixing when installing the drain valve, and can also achieve sealing and leak prevention through a specific structure. In specific implementation, its specifications can be set or selected according to the location where the drain valve needs to be connected.
[0046] See also Figure 2 As shown, according to some embodiments of the utility model, a limit groove is provided on the joint insert 6, and the first sealing gasket 4 is arranged in the limit groove and seals with the limit groove. Since the first sealing gasket 4 has a certain elasticity, it can be installed in the limit groove and can be tightly abutted against the wall of the limit groove under the action of elastic deformation, thereby achieving end face sealing cooperation to improve the sealing performance of the sewage valve.
[0047] In addition, during the processing, the limiting groove can also position the first sealing gasket 4, and there is no need to provide an additional structure for fixing the first sealing gasket 4 in the mold. Only the joint insert 6 needs to be fixed.
[0048] See also Figure 2As shown, according to some embodiments of the utility model, the valve shaft 3 and the valve ball 2 are integrated. In the prior art, since the valve ball 2 and the valve shaft 3 are usually connected by a snap-fitting method, it is necessary to additionally set a snap-fitting structure on the valve ball 2 and the valve shaft 3, which is relatively complicated to process, and it is necessary to set an additional process to assemble the valve ball 2 and the valve shaft 3. The utility model integrates the valve ball 2 and the valve shaft 3, thereby eliminating the need to set a connecting structure on the valve ball 2 and the valve shaft 3, and can save the assembly process of the valve ball 2 and the valve shaft 3, and can make the structure of the valve ball 2 and the valve shaft 3 more stable and compact.
[0049] See also Figure 2 As shown, according to some embodiments of the present invention, a sealing ring 7 is provided between the valve shaft 3 and the valve body 1. By providing the sealing ring 7 between the valve shaft 3 and the valve body 1, the sealing performance of the sewage valve can be enhanced, and the position of the valve shaft 3 is convenient for setting the sealing structure, which can prevent the space of the valve cavity from being occupied.
[0050] Specifically, see Figure 2 As shown, in this embodiment, a sealing groove is provided on the valve body 1, a sealing ring 7 is provided in the sealing groove and sleeved on the valve shaft 3, and the sealing ring 7 is respectively sealed with the sealing groove and the valve shaft 3 under the action of elastic deformation. The sealing ring 7 can adopt a common O-ring.
[0051] According to some embodiments of the present invention, under the premise of satisfying the spatial layout, if it is necessary to strengthen the sealing effect between the valve shaft 3 and the valve body 1 , multiple sealing rings 7 (such as two) can be arranged at intervals along the axial direction of the valve shaft 3 .
[0052] See also Figure 2 As shown, according to some embodiments of the utility model, the sewage valve further includes a check ring 8 for limiting the sealing ring 7, and the check ring 8 is arranged on the outside of the sealing ring 7. By arranging the check ring 8 on the outside of the sealing ring 7, the sealing ring 7 can be limited to prevent it from moving along the axial direction of the valve shaft 3.
[0053] Specifically, in this embodiment, a mounting groove for installing the check ring 8 is provided on the valve body 1, and the check ring 8 includes a mounting portion and a limiting portion which are connected to each other, and the mounting portion has a certain elasticity. After the check ring 8 is arranged in the mounting groove, the mounting portion elastically abuts against the inner wall of the mounting groove, and the limiting portion abuts against the sealing ring 7 to limit it.
[0054] See also Figure 3 and Figure 4As shown, according to some embodiments of the utility model, the drain valve further includes a valve cover 9 and a handle 10, the valve cover 9 is connected to the valve shaft 3, the handle 10 includes a fixed section 10a and a folding section 10b, the fixed section 10a is connected to the valve cover 9, and the folding section 10b is hinged to the fixed section 10a. By setting the handle 10 as the fixed section 10a and the folding section 10b, the handle 10 can be folded up when not in use, thereby saving space, so that the drain valve provided by the utility model can be adapted to be installed in a small space or an environment with dense pipelines. When the handle 10 is unfolded, it can provide a larger operating lever, making the operation easier and more convenient, reducing the force required by the user to open or close the drain valve, and reducing the difficulty of operation.
[0055] Specifically, after the handle 10 is folded, the position of the folding section 10b can be fixed by a fixing mechanism, or the fixing section 10a and the folding section 10b can be hingedly connected by a hinge shaft with a certain damping.
[0056] See also Figure 3 and Figure 4 As shown, according to some embodiments of the utility model, in the folded state, the folding section 10b is located on one side of the valve body 1. The folding section 10b is located on one side of the drain valve body 1, rather than facing the pipeline or other directions, so that it will not protrude into the space of the pipeline or other equipment, thereby avoiding interference with the surrounding environment, which is particularly important for drain valves installed in narrow or crowded areas, and can ensure that the folding section 10b will not be restricted or collided by surrounding equipment or pipelines. It can also further reduce the space occupied by the drain valve in the closed state. In addition, the folding section 10b is located on one side of the valve body 1, which can make the drain valve more neat and beautiful in the closed state.
[0057] See also Figures 2 to 4 As shown, according to some embodiments of the utility model, the drain valve further includes a union joint 11, which is rotatably connected to the valve body 1. During installation, the union joint 11 allows the drain valve to have a certain rotation range. When the installation position is not ideal or the pipeline direction has a certain deviation, the direction of the drain valve can be adjusted by rotating the union joint 11 to ensure that the connection direction between the drain valve and the pipeline is correct, thereby improving the flexibility of installation. For example, when there is a certain degree of vibration or deformation in the pipeline system, the union joint 11 can help the drain valve adapt to the connection with the pipeline and maintain a good connection with the pipeline.
[0058] Specifically, see Figure 2 As shown, in this embodiment, the flexible joint 11 is configured to be rotatably connected to the valve body 1 through the joint insert 6.
[0059] See also Figures 2 to 4As shown, according to some embodiments of the utility model, in order to better protect the inner tank of the water heater, a bracket fixing position is provided on the joint inlay 6, and a magnesium rod bracket 12 is provided on the bracket fixing position. The magnesium rod bracket 12 and the joint inlay 6 can be threaded or fixed by snaps.
[0060] See below Figures 1 to 4 The sewage valve provided by the utility model is described with a specific example.
[0061] The sewage valve provided by the utility model comprises a valve body 1, a valve cover 9, a handle 10, a valve ball 2, a valve shaft 3, a first sealing gasket 4, a second sealing gasket 5, a joint inlay 6, a flexible joint 11 and a magnesium rod bracket 12.
[0062] A valve cavity, a first flow channel and a second flow channel are formed in the valve body 1, the first flow channel and the second flow channel are both connected to the valve cavity, the valve ball 2 is arranged in the valve cavity, the valve shaft 3 is connected to the valve ball 2, the first sealing gasket 4 is arranged in the valve body 1, the first sealing gasket 4 is used to seal with the valve ball 2 to close the first flow channel, the second sealing gasket 5 is arranged in the valve body 1, the first sealing gasket 4 is used to seal with the valve ball 2 to close the second flow channel; one end of the joint insert 6 is arranged in the first flow channel, the first sealing gasket 4, the second sealing gasket 5 and the joint insert 6 are all integrated with the valve body 1, which can improve the compactness and stability of the sewage valve and simplify the assembly process.
[0063] The joint insert 6 is provided with a limit groove, and the first sealing gasket 4 is arranged in the limit groove and seals with the limit groove. By providing the limit groove, the first sealing gasket 4 can achieve end face sealing with the joint insert 6, thereby improving the sealing performance of the drain valve, and at the same time, it can also simplify the processing technology and improve production efficiency.
[0064] The valve shaft 3 and the valve ball 2 are integrated. No additional connection structure is required between the valve shaft 3 and the valve ball 2. The processing technology can be simplified, the assembly process can be omitted, and the structure can be made more stable and compact.
[0065] A sealing ring 7 is provided between the valve shaft 3 and the valve body 1. The sealing performance of the drain valve can be enhanced, and the position of the valve shaft 3 is convenient for setting the sealing structure, which can prevent the space of the valve cavity from being occupied. A check ring 8 is provided on the outside of the sealing ring 7 for limiting the sealing ring 7. The check ring 8 can limit the sealing ring 7 to prevent it from moving along the axial direction of the valve shaft 3.
[0066] The valve cover 9 is connected to the valve shaft 3, and the handle 10 includes a fixed section 10a and a folding section 10b, wherein the fixed section 10a is connected to the valve cover 9, and the folding section 10b is hinged to the fixed section 10a, and in the folded state, the folding section 10b is located at one side of the valve body 1. By configuring the handle 10 as the fixed section 10a and the folding section 10b, it can be folded up when not in use to save space, so that the sewage valve can be installed in a narrow space or an environment with dense pipelines.
[0067] The union 11 is rotatably connected to the valve body 1 through the union insert 6. During installation, the union 11 can be rotated within a certain range. Even if the installation position is not ideal or the pipeline direction is deviated, the union 11 can be rotated to ensure correct connection with the pipeline, thereby improving installation flexibility.
[0068] A bracket fixing position is provided on the joint inlay 6, and the magnesium rod bracket 12 is provided at the bracket fixing position. The magnesium rod bracket 12 and the joint inlay 6 can be fixed by threaded connection or snap fastening.
[0069] The water heater provided in the embodiment of the utility model comprises the drain valve as described in any one of the above embodiments.
[0070] The water heater provided by the utility model adopts the above-mentioned drain valve, so the risk of loosening or misalignment of the drain valve gasket can be reduced, the connection between the gasket and the valve body 1 can be ensured to be tighter, the stability of the gasket can be improved, and the reliability of the drain valve can be improved. In addition, the number of parts can be reduced, the manufacturing and assembly process can be simplified, and the production cost can be reduced.
[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.
Claims
1. A drain valve, characterized in that: include: A valve body, wherein a valve cavity, a first flow channel and a second flow channel are formed in the valve body, and the first flow channel and the second flow channel are both connected to the valve cavity; a valve ball, the valve ball being disposed in the valve cavity; a valve shaft connected to the valve ball; a first sealing gasket, the first sealing gasket being disposed in the valve body and being used for sealingly cooperating with the valve ball to close the first flow channel; a second sealing gasket, the second sealing gasket being disposed in the valve body, and the second sealing gasket being used for sealingly cooperating with the valve ball to close the second flow channel; The first sealing gasket and the second sealing gasket are both integrated with the valve body.
2. The drain valve according to claim 1, characterized in that: It also includes a joint inlay, one end of which is arranged in the first flow channel, and the joint inlay is integrated with the valve body.
3. The drain valve according to claim 2, characterized in that: The joint inlay is provided with a limiting groove, and the first sealing gasket is arranged in the limiting groove and is sealed with the limiting groove.
4. The drain valve according to claim 1, characterized in that: The valve shaft and the valve ball are integrated.
5. The drain valve according to claim 1, characterized in that: A sealing ring is arranged between the valve shaft and the valve body.
6. The drain valve according to claim 5, characterized in that: It also includes a non-return ring for limiting the position of the sealing ring, and the non-return ring is arranged on the outside of the sealing ring.
7. The sewage valve according to any one of claims 1 to 6, characterized in that: It also includes a valve cover and a handle, wherein the valve cover is connected to the valve shaft, and the handle includes a fixed section and a folding section, wherein the fixed section is connected to the valve cover, and the folding section is hinged to the fixed section.
8. The drain valve according to claim 7, characterized in that: In the folded state, the folded section is located at one side of the valve body.
9. The sewage valve according to any one of claims 1 to 6, characterized in that: It also includes a flexible joint, which is rotatably connected to the valve body.
10. A water heater, characterized in that: Comprising a drain valve as claimed in any one of claims 1 to 9.