A plastic-coated double-seal valve head and pre-filter

Abstract

The application provides a plastic-coated double-sealing valve head and a front filter, which comprises a valve head body, the inside of the valve head body is provided with a mounting cavity; an inner insert is arranged in the mounting cavity, the inner insert is enclosed to form a water inlet flow channel and a water outlet flow channel which are not communicated with each other, the water inlet flow channel is used for connecting the inner cavity of a filter bottle, the water outlet flow channel is used for connecting the inner cavity of a filter core, the water inlet end of the water inlet flow channel is provided with a water inlet port, and the water outlet end of the water outlet flow channel is provided with a water outlet port; and the inner insert is a PPR inner insert. The double-sealing structure of the valve head body internally sleeving the inner insert is adopted to replace the copper-coated plastic valve head on the market, the double-sealing structure plays a role in isolating heavy metals, is convenient to process, can effectively reduce the manufacturing cost, and is easy to install and maintain.

Description

Technical Field

[0001] This application relates to the field of purification equipment technology, and more specifically, to a plastic-coated double-seal valve head. This application also provides a pre-filter including the aforementioned plastic-coated double-seal valve head. Background Technology

[0002] The city's water supply pipelines are old and long. Rust, silt and other impurities in the pipelines can cause water-using equipment to malfunction. Therefore, it is necessary to install pre-filters on the pipelines to filter out impurities and improve the water quality downstream of the pre-filter.

[0003] A pre-filter is the first coarse filtration device for the whole house's water supply. It can filter out sediment, rust, and large particles in tap water, preventing the large amount of sediment and impurities generated in the water supply network from causing harm to the human body. It can also provide pre-protection for concealed pipes, faucets, plumbing, water heaters, boilers, central air conditioning, washing machines, dishwashers, coffee machines, and other water appliances (such as water purifiers, reverse osmosis systems, and water softeners).

[0004] The valve heads in existing pre-filters are all made of metal. They are made of pure metal or metal with a layer of plastic injected into it to isolate heavy metals from the water. The manufacturing cost is high and the process is complex. Due to the instability of the injection molding process (e.g., mold damage, poor injection molding, etc.), the valve head is very easy to be defective. Once a defect occurs, it cannot be reworked, resulting in a high defect rate of valve heads and increasing production costs. Utility Model Content

[0005] This application provides a plastic-coated double-seal valve head, which adopts a double-seal structure with an embedded component inside the valve head body, replacing the copper-coated plastic valve head on the market. It not only isolates heavy metals, but is also easy to process, effectively reducing manufacturing costs and making it easy to install and maintain.

[0006] This application provides a plastic-coated double-seal valve head, comprising:

[0007] A valve head body, wherein the valve head body has an internal mounting cavity;

[0008] An insert is disposed in the mounting cavity. The insert has an internal enclosure forming a non-communicating inlet channel and an outlet channel. The inlet channel is used to connect to the inner cavity of the filter bottle, and the outlet channel is used to connect to the inner cavity of the filter element. The inlet end of the inlet channel is provided with an inlet, and the outlet end of the outlet channel is provided with an outlet. The insert is a PPR insert.

[0009] In some embodiments, the embedded component includes an embedded main body and a first connector and a second connector disposed at both ends of the embedded main body. The first connector encloses a first water inlet sub-channel, and the second connector encloses a first water outlet sub-channel. The water inlet end of the first water inlet sub-channel is provided with a water inlet, and the water outlet end of the first water outlet sub-channel is provided with a water outlet.

[0010] The embedded main body is provided with a partition, which divides the inner cavity of the embedded main body into a second water inlet sub-channel and a second water outlet sub-channel that are not interconnected. The second water inlet sub-channel is connected to the first water inlet sub-channel and the inner cavity of the filter bottle, and the first water outlet sub-channel is connected to the second water outlet sub-channel and the inner cavity of the filter element.

[0011] In some embodiments, the mounting cavity is distributed along the first direction on the valve head body, and the first connector and the second connector are respectively disposed at both ends of the embedded body member along the first direction.

[0012] In some embodiments, the embedded main body is integrally connected to the first and second connecting pipes, or the embedded main body is separately and sealed to the first and second connecting pipes.

[0013] In some embodiments, the system further includes two connectors, each connector having an annular rib and an annular groove. A sealing ring is provided in the annular groove, and the sealing ring is used to seal the inner wall side of the second connector. A sealing gasket is provided on the annular rib facing the end face of the first connector or the second connector. The connector and the first connector, as well as the connector and the second connector, are sealed together by the sealing ring and the sealing gasket.

[0014] In some embodiments, the separator includes a vertical baffle and a surrounding baffle disposed in the inner cavity of the embedded main body. The vertical baffle is perpendicular to the inner cavity wall of the embedded main body and connected to the surrounding baffle. The vertical baffle has a first sidewall and a second sidewall respectively on both sides along a first direction. The inner cavity of the embedded main body, the vertical baffle, and the outer wall of the surrounding baffle communicate to form a second water inlet sub-channel. The inner cavity of the embedded main body, the vertical baffle, and the inner wall of the surrounding baffle communicate to form a second water outlet sub-channel.

[0015] In some embodiments, the plastic-coated double-seal valve head further includes a pressure gauge;

[0016] The valve head body is provided with a first mounting part, the embedded main body is provided with a second mounting part, and the pressure gauge is inserted into and sealed with the first mounting part and the second mounting part.

[0017] In some embodiments, the first mounting part has a positioning groove inside, and the second mounting part has a positioning step, the positioning step being adapted to the positioning groove for positioning.

[0018] This application also provides a pre-filter, including a valve head, a filter bottle connected to the valve head, a filter element disposed inside the filter bottle, and a valve connected to the bottom of the filter bottle, wherein the valve head is a plastic-coated double-seal valve head as described in the above embodiments.

[0019] In some embodiments, the filter element has an internal scale-inhibiting filter media layer, which is used to prevent scale formation.

[0020] The plastic-coated double-seal valve head provided in this application adopts a double-seal structure with an embedded component inside the valve head body, replacing the copper-coated plastic valve head on the market. It is easy to process, easy to install, and has a lower production cost. While playing the role of isolating heavy metals, it can effectively reduce manufacturing costs and is easy to maintain. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0022] Figure 1 A schematic diagram of a plastic-coated double-seal valve head provided in some embodiments of this application;

[0023] Figure 2 A schematic diagram of a plastic-coated double-seal valve head in a filtering state, provided in some embodiments of this application;

[0024] Figure 3 A schematic diagram showing the plastic-coated double-seal valve head in a backwashing state, as provided in some embodiments of this application;

[0025] Figure 4 A cross-sectional view of the connector in a plastic-coated double-seal valve head provided in some embodiments of this application;

[0026] Figure 5 This is a schematic diagram of the valve head body in a plastic-coated double-seal valve head provided in some embodiments of this application;

[0027] Figure 6 A schematic diagram of the embedded part in the plastic-coated double-seal valve head provided in some embodiments of this application;

[0028] Figure 7 A schematic diagram of the first connecting pipe in a plastic-coated double-seal valve head provided in some embodiments of this application;

[0029] Figure 8 This is a cross-sectional view of the first connecting pipe in a plastic-coated double-seal valve head provided in some embodiments of this application.

[0030] The attached figures are labeled as follows:

[0031] 1-Valve head body; 2-Embedded main component; 3-First connecting pipe; 4-Second connecting pipe; 5-Connector; 6-Nut; 7-Filter bottle; 8-Filter element; 9-Seal; 10-Valve; 11-Pressure gauge;

[0032] 101 - Threads at both ends; 102 - Top thread; 103 - Bottom thread; 104 - First mounting part; 201 - Separator; 202 - Second inlet sub-channel; 203 - Second outlet sub-channel; 204 - Second mounting part; 301 - Inlet; 302 - First inlet sub-channel; 303 - Inner wall of the connector; 304 - Right port; 401 - Outlet; 402 - First outlet sub-channel; 501 - Annular rib; 502 - Annular groove;

[0033] 2011 - Vertical stop; 2012 - Enclosure; 1041 - Positioning groove; 2041 - Positioning step;

[0034] X - First direction. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, 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.

[0036] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. The terms "first," "second," etc., are used to distinguish different objects, not to describe a particular order or hierarchy.

[0037] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0038] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" 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 direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0039] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0040] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0041] In this application, "multiple" means two or more (including two).

[0042] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of the plastic-coated double-seal valve head provided in this application.

[0043] This application provides a plastic-coated double-sealed valve head, mainly including a valve head body 1 and an insert. The valve head body 1 has an internal mounting cavity, and the insert is disposed in the mounting cavity. The interior of the insert forms an inlet channel and an outlet channel that are not interconnected. The inlet channel is used to connect to the inner cavity of the filter bottle 7, and the outlet channel is used to connect to the inner cavity of the filter element 8. The inlet end of the inlet channel is provided with an inlet 301, and the outlet end of the outlet channel is provided with an outlet 401. The insert is made of thermoplastic material.

[0044] The valve head body 1 is used to accommodate and fix the insert, and through its internal mounting cavity, it cooperates with the insert to guide and seal the water flow. The mounting cavity accommodates the insert, and its shape and size match the shape and size of the insert to ensure that the insert can be tightly and stably embedded in the mounting cavity of the valve head body 1, and to form a good seal between them. In addition, the mounting cavity can withstand a certain water pressure to ensure that the valve head body 1 will not be deformed or damaged by water pressure impact during operation.

[0045] The embedded part can be fixedly installed in the mounting cavity through structural positioning, tight fitting, or adhesive bonding to ensure that it will not shift during water flow. The embedded part can be made of thermoplastic plastic (e.g., PVC or PPR). The embedded part isolates the valve head body 1 from the water, preventing heavy metals from leaching into the water and causing water pollution due to direct contact between the valve head body 1 and the water. In addition, the embedded part has good mechanical properties and corrosion resistance, further improving the stability and service life of the entire valve head.

[0046] In addition, the gap between the mounting cavity and the insert can be sealed by a sealing element 9 (e.g., O-ring, sealant, etc.) to prevent water from leaking from the gap between the mounting cavity and the insert.

[0047] The embedded component has an inlet channel and an outlet channel inside, which are not connected to each other. The inlet end of the inlet channel has an inlet 301, and the outlet end of the outlet channel has an outlet 401. Optionally, the inlet 301 and outlet 401 of the embedded component are aligned with the inlet 301 and outlet 401 on the valve head body 1, respectively, to ensure smooth water flow and prevent water leakage from the interface.

[0048] When water enters the valve head body 1, it first enters the inner cavity of the filter bottle 7 through the inlet 301 of the insert and the inlet channel. After being filtered by the filter element 8 inside the filter bottle 7, the water flows through the outlet channel of the insert and finally flows out from the outlet 401, thereby guiding the water flow into the interior of the filter bottle 7.

[0049] In one specific embodiment, the embedded component includes an embedded main body 2 and a first connecting pipe 3 and a second connecting pipe 4 respectively disposed at both ends of the embedded main body 2. The first connecting pipe 3 internally encloses to form a first water inlet sub-channel 302, and the second connecting pipe 4 internally encloses to form a first water outlet sub-channel 402. The water inlet end of the first water inlet sub-channel 302 is provided with a water inlet 301, and the water outlet end of the first water outlet sub-channel 402 is provided with a water outlet 401. A partition 201 is provided inside the embedded main body 2, which divides the inner cavity of the embedded main body 2 into a second water inlet sub-channel 202 and a second water outlet sub-channel 203 that are not interconnected.

[0050] refer to Figure 7 The first connector 3 and the second connector 4 are made of thermoplastic plastic, and are thermofused to the embedded main body 2. Figure 7 For example, after the right port 304 of the first connector 3 is hot-melted, it is connected and fixed to the embedded main body 2. The welding machine is stable and the process is simple and quick, saving time and effort. When there are defective products, they can be softened and pulled out with a hot air gun, which reduces the cost. The joint 5 can also adopt a gasket compression seal and a sealing ring side wall seal solution, which solves the risk of water leakage caused by the poor sealing of the joint 5.

[0051] In some embodiments, the mounting cavity is distributed along the first direction X on the valve head body 1, and the first connecting pipe 3 and the second connecting pipe 4 are respectively disposed at both ends of the embedded body member 2 along the first direction X. Figure 1 As shown, the mounting cavity is horizontally distributed, and the first connecting pipe 3 and the second connecting pipe 4 are distributed horizontally at both ends of the embedded main body 2. This structure makes the layout of the water channel more reasonable and improves the smoothness of water flow.

[0052] The embedded main body 2 can be integrally connected to the first connecting pipe 3 and the second connecting pipe 4, for example, by heat fusion, or they can be connected separately and sealed using the sealing element 9. This ensures the overall structural stability of the embedded main body 2 while improving the sealing performance.

[0053] Furthermore, the plastic-coated double-sealed valve head in this embodiment is also provided with two connectors 5. Each connector 5 is provided with an annular rib 501 and an annular groove 502. The annular rib 501 can position the first connecting pipe 3 and the valve head body 1, or the second connecting pipe 4 and the valve head body 1. After the valve head body 1 and the connector 5 are connected by the nut 6, the annular rib 501 positions the first connecting pipe 3 and the valve head body 1 or the second connecting pipe 4 and the valve head body 1. In addition, a sealing ring is provided in the annular groove 502. The sealing ring is used to seal the inner wall side of the second connecting pipe 4. A sealing gasket is installed on the end face of the annular rib 501 facing the first connecting pipe 3 or the second connecting pipe 4. The connector 5 and the first connecting pipe 3, as well as the connector 5 and the second connecting pipe 4, are sealed and connected by compression through the sealing ring and the sealing gasket, thus forming a double-sealed valve head structure, which can significantly increase the sealing performance of the plastic-coated double-sealed valve head.

[0054] Therefore, in the case of existing lead-proof valve heads (copper-clad plastic valve heads) that use internal injection-molded plastic to isolate heavy metals in a single-seal structure, the valve head of this application embodiment uses an embedded part inside the valve head body 1, and the embedded part is connected by hot-melt welding. Since the welding machine is stable and the process is simple and quick, it saves time and effort. If there are defective products, they can be softened and pulled out with a hot air gun, which reduces the processing cost. The connection point uses a gasket compression seal and a sealing ring sidewall seal, which solves the problem of water leakage caused by the poor sealing between the embedded part and the two end connection points.

[0055] Optionally, the insert is a PPR insert. PPR (Polypropylene Random Copolymer) has good corrosion resistance and mechanical properties, which helps to extend the service life of the insert.

[0056] refer to Figure 6 and combined Figure 1In one specific embodiment, the separator 201 includes a vertical baffle 2011 and a surrounding baffle 2012 disposed in the inner cavity of the embedded main body 2. The vertical baffle 2011 is perpendicular to the inner cavity wall of the embedded main body 2 and connected to the surrounding baffle 2012. The vertical baffle 2011 has a first sidewall and a second sidewall respectively on both sides along the first direction X. The inner cavity of the embedded main body 2, the outer walls of the vertical baffle 2011 and the surrounding baffle 2012 are connected to form a second water inlet sub-channel 202. The inner cavity of the embedded main body 2, the inner walls of the vertical baffle 2011 and the surrounding baffle 2012 are connected to form a second water outlet sub-channel 203.

[0057] Please refer to Figure 2 and Figure 3 In filtration mode, source water enters through the inlet pipe, flows into the inlet end of the embedded main body 2 inside the valve head, passes through the first inlet sub-channel 302 into the second inlet sub-channel 202, and then enters the filter bottle 7. After being filtered by the filter screen, it passes through the second outlet sub-channel 203 and the first outlet sub-channel 402 and exits from the outlet 401. In sewage discharge mode, the sewage discharge valve is opened, and the filter bottle 7 is under negative pressure. Raw water enters the filter bottle 7 through the first inlet sub-channel 302 and the second inlet sub-channel 202 of the embedded main body 2, and then passes through valve 10 to discharge sediment and impurities from the filter bottle 7.

[0058] refer to Figure 5 In one specific embodiment, the plastic-coated double-seal valve head further includes a pressure gauge 11. The top thread 102 of the valve head body 1 mates with the top thread 102 of the pressure gauge 11. The valve head body 1 has a first mounting portion 104, and the embedded main body 2 has a second mounting portion 204. The pressure gauge 11 is inserted into and threadedly sealed to the first mounting portion 104 and the second mounting portion 204. Thus, the pressure gauge 11 allows for real-time monitoring of the water flow pressure inside the flow channel, improving ease of use.

[0059] Furthermore, the first mounting part 104 is provided with a positioning groove 1041 inside, and the second mounting part 204 is provided with a positioning step 2041. The positioning step 2041 is adapted to the positioning groove 1041 for positioning, which improves the installation accuracy and stability of the pressure gauge 11.

[0060] This application embodiment also provides a pre-filter, including a valve head, connectors 5 respectively disposed at the inlet end and outlet end of the valve head, a filter bottle 7 connected to the valve head, a filter element 8 disposed inside the filter bottle 7, and a valve 10 connected to the bottom of the filter bottle 7.

[0061] The left and right ends of connector 5 are heat-fused to the water pipe, and the right protruding end of the annular rib 501 extends into the inner wall 303 of the connector. Figure 8As shown, the annular groove 502 is sealed with a sealing ring to the inner wall 303 of the first connecting pipe 3, or the annular groove 502 is sealed with the inner wall of the second connecting pipe 4 using a sealing ring. A sealing gasket is installed on the side end face of the annular rib 501 for compression sealing; this double-seal structure design maximizes safety. The nut 6 is threaded to the valve head body 1, fixing the connector 5 and tightening the gasket. The left and right ends of the valve head body 1 are connected to the nut 6 using threads 101 at both ends, and the lower thread 103 is connected to the filter bottle 7. The left end of the valve head body 1 is the inlet 301, and the right end is the outlet 401.

[0062] In addition, a sealing element 9 is provided at the bottom of the bottle body. The sealing element 9 is threadedly connected to the valve head body 1. A groove is provided at the connection between the sealing element 9 and the valve head body 1. The groove is equipped with a sealing ring, which seals the gap between the filter bottle 7 and the sealing element 9 to prevent water from flowing out from the gap. The valve body is equipped with a switch knob. By operating the switch knob, the wastewater can be flushed and discharged. Opening the valve body allows wastewater to be discharged, and closing the valve body restores the filtration state.

[0063] The valve head in this embodiment is the plastic-coated double-seal valve head described in any of the above embodiments. This pre-filter has good sealing performance and an efficient water flow channel design, which improves filtration efficiency.

[0064] In some embodiments, the filter element 8 is provided with a scale-inhibiting filter media layer to prevent scale buildup. This design further improves the filtration efficiency of the pre-filter and extends the service life of the filter element 8.

[0065] The above provides a detailed description of the plastic-coated double-seal valve head and pre-filter provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of this application. It should be noted that those skilled in the art can make various improvements and modifications to this application without departing from its principles, and these improvements and modifications also fall within the protection scope of this application.

Claims

1. A plastic-coated double-seal valve head, characterized in that, include: The valve head body (1) has an internal mounting cavity; An insert is disposed in the mounting cavity. The insert has an internal enclosure forming a non-communicating inlet channel and an outlet channel. The inlet channel is used to connect the inner cavity of the filter bottle (7), and the outlet channel is used to connect the inner cavity of the filter element (8). The inlet end of the inlet channel is provided with an inlet (301), and the outlet end of the outlet channel is provided with an outlet (401). The embedded component is a PPR embedded component.

2. The plastic-coated double-seal valve head according to claim 1, characterized in that, The embedded component includes an embedded main body (2), and a first connector (3) and a second connector (4) respectively disposed at both ends of the embedded main body (2). The first connector (3) is enclosed to form a first water inlet sub-channel (302), and the second connector (4) is enclosed to form a first water outlet sub-channel (402). The water inlet end of the first water inlet sub-channel (302) is provided with a water inlet (301), and the water outlet end of the first water outlet sub-channel (402) is provided with a water outlet (401). The embedded main body (2) is provided with a partition (201) inside. The partition (201) divides the inner cavity of the embedded main body (2) into a second water inlet sub-channel (202) and a second water outlet sub-channel (203) that are not connected to each other. The second water inlet sub-channel (202) is connected to the inner cavity of the first water inlet sub-channel (302) and the filter bottle (7). The first water outlet sub-channel (402) is connected to the inner cavity of the second water outlet sub-channel (203) and the filter element (8).

3. The plastic-coated double-seal valve head according to claim 2, characterized in that, The mounting cavity is distributed along the first direction on the valve head body (1), and the first connecting pipe (3) and the second connecting pipe (4) are respectively disposed at both ends of the embedded main body (2) along the first direction.

4. The plastic-coated double-seal valve head according to claim 2, characterized in that, The embedded main body (2) is integrally connected to the first pipe (3) and the second pipe (4), or the embedded main body (2) is separately and sealed to the first pipe (3) and the second pipe (4).

5. The plastic-coated double-seal valve head according to claim 4, characterized in that, It also includes two connectors (5), each connector (5) having an annular rib (501) and an annular groove (502). A sealing ring is provided in the annular groove (502), which is used to seal the inner wall side of the second pipe (4). A sealing gasket is provided on the annular rib (501) facing the end face of the first pipe (3) or the second pipe (4). The connector (5) is sealed and connected to the first pipe (3) and to the second pipe (4) through the sealing ring and the sealing gasket.

6. The plastic-coated double-seal valve head according to any one of claims 2 to 5, characterized in that, The separator (201) includes a vertical baffle (2011) and a surrounding baffle (2012) disposed in the inner cavity of the embedded main body (2). The vertical baffle (2011) is perpendicular to the inner cavity wall of the embedded main body (2) and connected to the surrounding baffle (2012). The vertical baffle (2011) has a first side wall and a second side wall respectively on both sides along the first direction. The inner cavity of the embedded main body (2), the outer walls of the vertical baffle (2011) and the surrounding baffle (2012) are connected to form the second water inlet sub-channel (202). The inner cavity of the embedded main body (2), the inner walls of the vertical baffle (2011) and the surrounding baffle (2012) are connected to form the second water outlet sub-channel (203).

7. The plastic-coated double-seal valve head according to claim 4, characterized in that, The plastic-coated double-seal valve head also includes a pressure gauge (11); The valve head body (1) is provided with a first mounting part (104), the embedded main body (2) is provided with a second mounting part (204), and the pressure gauge (11) is inserted into and sealed with the first mounting part (104) and the second mounting part (204).

8. The plastic-coated double-seal valve head according to claim 7, characterized in that, The first mounting part (104) has a positioning groove (1041) inside, and the second mounting part (204) has a positioning step (2041), which is adapted to the positioning groove (1041) for positioning.

9. A pre-filter, comprising a valve head, a filter bottle (7) connected to the valve head, a filter element (8) disposed inside the filter bottle (7), and a valve (10) connected to the bottom of the filter bottle (7), characterized in that, The valve head is the plastic-coated double-seal valve head as described in any one of claims 1 to 8.

10. The pre-filter according to claim 9, characterized in that, The filter element (8) is provided with a scale-inhibiting filter media layer inside, which is used to prevent scale formation.

Images