Three-way switching valve

Abstract

The utility model provides a three-way switching valve which comprises a shell, and two valve cavities and a liquid outlet flow channel are arranged in the shell. The communicating flow channel is located between the two valve cavities, valve seats are arranged at the two ends of the communicating flow channel, and the communicating flow channel communicates with the two valve cavities through the two valve seats; the liquid inlet flow channel is arranged at the side part of the communicating flow channel and communicates with the communicating flow channel; the two diaphragms can abut against the valve seat to seal the valve seat; at least one driving assembly is arranged; the valve rod is located in the communicating flow channel, and the two ends of the valve rod are connected with the two diaphragms respectively; the liquid inlet flow channel is provided with a port communicated with the communicating flow channel, a vertical plane is taken as a reference plane, on the projection of the reference plane, the central axis of the valve rod coincides with the center of the port, the port is provided with an opposite part opposite to the valve rod and receding parts located on the two sides of the opposite part, the total area of the receding parts is set as S1, the total area of the opposite part is set as S2, S1 / S2 is larger than or equal to 0.3, and S1 / S2 is larger than or equal to 0.3. The valve has the advantage of weakening vibration of structures such as the valve body and the diaphragm.

Description

Technical Field

[0001] The utility model relates to the technical field of valves, in particular to a three-way switching valve. Background Art

[0002] The diaphragm valve can separate the flow channel part and the non-flow channel part of the valve body through the diaphragm, so it can prevent the non-flow channel part from contaminating the fluid in the flow channel part, thereby ensuring that the valve body has a high degree of cleanliness. Therefore, it is often used in industries such as semiconductors and medicine to achieve high-purity fluid delivery control.

[0003] Specifically, the valve assembly disclosed in patent application publication number US5967173A includes a poppet valve assembly that contacts the second diaphragm and is connected to the third diaphragm, moving with the diaphragms. The poppet valve assembly includes a lower valve plug, an upper valve plug, and a valve stem connecting the valve plugs. The valve stem controls the engagement of the lower or upper valve plug with the valve seat, opening or blocking the corresponding inlet. One end of the valve stem is integrally formed with either the upper or lower valve plug. The valve stem extends through the center of the valve body and is removably connected to the other valve plug at its other end.

[0004] As disclosed above, in the valve assembly, the fluid enters the cylindrical chamber from the inlet and directly impacts the valve stem. The side of the valve stem will be subjected to the impact force of the fluid. In order to prevent the valve stem from being easily deformed, the interior of the valve stem will be set as a hollow structure and an inserted shaft will be provided inside. However, this will increase the overall volume of the valve body, resulting in a larger space occupied by the valve body when installed and used. At the same time, the fluid in the flow channel is affected by the pump body, and the fluid pressure will always be in a fluctuating state. Therefore, the impact force on the valve stem will also continue to change. The constantly changing force will cause the valve stem to vibrate, and further cause the diaphragm and other structures to vibrate. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the defects in the prior art, thereby providing a three-way switching valve. To achieve the above object, the present invention adopts the following technical solutions:

[0006] A three-way switching valve, comprising:

[0007] A housing, wherein two valve cavities and a liquid outlet channel communicating with the two valve cavities are provided inside the housing;

[0008] A communication channel is located between the two valve chambers, with valve seats provided at both ends of the communication channel, and is connected to the two valve chambers through the two valve seats respectively;

[0009] a liquid inlet channel, the liquid inlet channel being arranged on the side of the communication channel and being in communication with the communication channel;

[0010] Two diaphragms are respectively arranged in the two valve cavities and can abut against the valve seat to seal the valve seat;

[0011] There is at least one drive assembly, which is arranged on the side of the diaphragm away from the communicating flow channel to control the movement of the diaphragm;

[0012] The three-way switching valve also includes:

[0013] A valve stem is located inside the communication channel, with both ends of the valve stem connected to the two diaphragms respectively, and the valve stem can separate at least one diaphragm from the valve seat to open the valve seat;

[0014] The liquid inlet channel has a port connected to the connecting channel. Taking a vertical plane as a reference plane, on the projection of the reference plane, the central axis of the valve stem and the center of the port are arranged to coincide with each other, wherein the port has a facing portion opposite to the valve stem and avoidance portions located on both sides of the facing portion. The total area of ​​the avoidance portion is S1, and the total area of ​​the facing portion is S2, wherein S1 / S2 ≥ 0.3.

[0015] In the above technical solution, by providing the avoidance portion, when the fluid is introduced from the liquid inlet channel provided on the side of the connecting channel, the fluid at the avoidance portion will not directly flush the valve stem, thereby reducing the flushing force on the valve stem. At the same time, in this case, when the pressure of the fluid fluctuates, the change in the force acting on the valve stem will also decrease, thereby reducing the change in pressure on the valve stem and weakening the vibration of structures such as the valve body and diaphragm. At the same time, since the facing portion is positively correlated with the diameter of the valve stem, a reasonable setting of the area ratio of the facing portion to the avoidance portion can not only reduce the force acting on the valve stem and the change in the force acting on the valve stem to reduce the vibration during use of the three-way valve, but also improve the valve stem's ability to resist deformation to a certain extent.

[0016] Preferably, in the projection of the reference plane, the two avoidance portions are symmetrically arranged about the central axis of the valve stem.

[0017] In the above technical solution, by setting the two avoidance parts as a structure symmetrical about the central axis of the valve stem, the valve stem can be subjected to more uniform force, avoiding vibration of the valve stem due to uneven force, and at the same time avoiding deformation and bending of the valve stem due to uneven force.

[0018] Preferably, an annular flow channel is formed between the outer wall of the valve stem and the inner side of the communicating flow channel, and the cross-sectional area of ​​the annular flow channel is larger than the cross-sectional area of ​​the liquid inlet flow channel.

[0019] In the above technical solution, by setting the cross-sectional area of ​​the annular flow channel to be larger, the flow rate of the fluid in the liquid inlet channel will be slowed down after entering the annular flow channel, thereby making the fluid flow inside the annular flow channel more stable, avoiding strong turbulence inside the annular flow channel due to the high fluid flow rate, which may cause valve stem vibration.

[0020] Preferably, the diaphragm includes an outer edge portion on a sealed fixed housing, a deformable portion located inside the outer edge portion, and a valve core located inside the deformable portion. The outer edge portion, the deformable portion, and the valve core are integrally formed, and movement of the valve core causes the deformable portion to deform.

[0021] Wherein, both ends of the valve stem are connected to the valve cores in the two diaphragms respectively, and the hardness of the valve stem is greater than the hardness of the diaphragm.

[0022] In the above technical solution, the diaphragm is set to an integrally formed structure of an outer edge portion, a deformation portion and a valve core, wherein the outer edge portion can maintain a stable seal with the shell, and the setting of the deformation portion can prevent the reciprocating motion of the valve core from affecting the sealing connection between the outer edge portion and the shell, and the valve core is used to cooperate with the valve stem so that the valve stem can stably support the valve core and realize the reciprocating motion of the valve stem and the valve core, thereby enabling the valve core to maintain a tight seal with the valve seat, or enabling the valve core to maintain a separation with the valve seat to conduct the corresponding flow channel.

[0023] It can be seen that in order to improve the sealing between the outer edge of the diaphragm and the shell, the valve core and the valve seat have abutting sealing effect. At the same time, to prevent the reciprocating motion of the valve core from affecting the sealing performance between the outer edge and the shell, the diaphragm usually has a certain deformation requirement, which leads to the fact that its own hardness cannot be set too large. In this solution, by setting the hardness of the valve stem to be greater than the hardness of the diaphragm, it can not only meet the deformation requirement of the diaphragm, but also use the valve stem to provide certain support to the diaphragm, thereby preventing the diaphragm from being excessively deformed and affecting its sealing. At the same time, a valve stem with a certain hardness can improve its own deformation resistance, so that the valve stem and valve core can reciprocate synchronously and stably. And through a valve stem with greater hardness, the diameter of the valve stem can be reduced to a certain extent, so as to reduce the volume of the entire three-way switching valve.

[0024] Preferably, the central axis of the liquid inlet channel is arranged perpendicular to the central axis of the valve stem.

[0025] In the above technical solution, the central axis of the liquid inlet channel is perpendicular to the central axis of the valve stem, which can avoid the situation where the liquid inlet channel is tilted and one of the diaphragms is opened, resulting in the impacted part of the valve stem being far away from the closed valve seat, causing the valve stem to be easily deformed.

[0026] Preferably, the liquid outlet channel has a communication port communicating with the valve cavity. In horizontal plane projection, the two communication ports are respectively located on both sides of the valve stem and are symmetrically arranged about the valve stem.

[0027] When fluid passes through the valve seat, the fluid flows faster near the connection port and slower near the other side, which can cause uneven force on the valve stem. This solution, by symmetrically arranging the two connection ports, ensures that when different valve seats are opened, the forces acting on the valve stem are opposite, preventing the valve stem from being subjected to a single-sided force, which can easily cause the valve stem to bend.

[0028] Preferably, two drive cavities are provided inside the housing, and the two drive cavities are respectively located on the side of the two diaphragms away from the valve cavity. The drive components are provided with two, namely a first drive component and a second drive component, and the first drive component and the second drive component are respectively located inside the two drive cavities;

[0029] The first driving assembly includes a spring and a spring support seat, wherein two ends of the spring respectively abut against one of the inner walls of the driving cavity and the spring support seat, and the spring support seat is connected to one of the diaphragms;

[0030] The second driving assembly includes a piston, which is sealingly and slidingly connected to the driving chamber on the other side, and the piston is connected to another diaphragm.

[0031] In the above technical solution, by respectively corresponding the first drive component and the second drive component to the diaphragms on both sides, and the spring of the first drive component and the piston of the second drive component cooperate with each other, the reciprocating drive of the two diaphragms can be achieved when power is applied on one side, so that the two diaphragms alternately resist against their corresponding valve seats, so that the control of the actual valve body is more convenient and simple.

[0032] Preferably, the two ends of the valve stem are connected to the two diaphragms in a radially limited manner;

[0033] The spring support seat is connected to one of the drive chamber side walls and the diaphragm radially to limit the swing of the diaphragm, and / or the piston is connected to the other drive chamber side wall and the diaphragm radially to limit the swing of the diaphragm.

[0034] In the above technical solution, the diaphragm is radially limited by the spring support seat and piston, thereby limiting the swing of the diaphragm and valve stem, ensuring the stability of the three-way valve operation, and also preventing the generation of debris due to friction between the various structures when the diaphragm and valve stem vibrate and swing. For example, friction between the valve core and the valve seat at the closed valve seat is avoided, which not only reduces the presence of friction particles, but also prevents the seal between the valve core and the valve seat from failing due to friction.

[0035] Preferably, the spring support seat has an extension wall extending downward and is radially limited by the extension wall and the side wall of the driving cavity. The height of the extension wall is greater than half the height of the driving cavity in which it is located.

[0036] In the above technical solution, the provision of the extension wall can increase the contact area between the spring support seat and the drive cavity, so that the spring support seat is more difficult to move radially relative to the drive cavity, thereby further improving the limiting effect of the spring support seat.

[0037] Preferably, the springs are provided in at least two groups, and different springs have different natural frequencies.

[0038] In the above technical solution, by setting the two groups of springs to have different natural frequencies, resonance between the diaphragm and the springs can be avoided.

[0039] Compared with the prior art, the present invention has at least the following beneficial effects:

[0040] 1. By setting up the avoidance portion, when the fluid is introduced from the liquid inlet channel provided on the side of the connecting channel, the fluid at the avoidance portion will not directly flush the valve stem, thereby reducing the flushing force on the valve stem. At the same time, in this case, when the pressure of the fluid fluctuates, the change in the force acting on the valve stem will also decrease, thereby reducing the change in pressure on the valve stem and weakening the vibration of structures such as the valve body and diaphragm. At the same time, since the facing portion is positively correlated with the diameter of the valve stem, a reasonable setting of the area ratio of the facing portion to the avoidance portion can not only reduce the force acting on the valve stem and the change in the force acting on the valve stem to reduce the vibration during the use of the three-way valve, but also improve the valve stem's ability to resist deformation to a certain extent.

[0041] 2. By setting the cross-sectional area of ​​the annular flow channel larger, the flow rate of the fluid in the liquid inlet channel will be slowed down after entering the annular flow channel, thereby making the fluid flow inside the annular flow channel more stable and avoiding strong turbulence inside the annular flow channel due to the high fluid flow rate, which may cause valve stem vibration.

[0042] 3. The diaphragm is configured to have an integrally formed outer edge, a deformable portion, and a valve core, wherein the outer edge is capable of maintaining a stable seal with the housing, and the deformable portion prevents the reciprocating motion of the valve core from affecting the sealed connection between the outer edge and the housing. The valve core is configured to cooperate with the valve stem so that the valve stem can stably support the valve core, achieving reciprocating motion between the valve stem and the valve core, thereby enabling the valve core to maintain a tight seal with the valve seat, or to maintain a separation between the valve core and the valve seat to conduct the corresponding flow path. It can be seen that in order to improve the sealing between the outer edge of the diaphragm and the housing, the valve core and the valve seat are in contact with each other to achieve a sealing effect. At the same time, to prevent the reciprocating motion of the valve core from affecting the sealing performance between the outer edge and the housing, the diaphragm generally has a certain deformation requirement, which means that its own hardness cannot be set too high. In this solution, by setting the hardness of the valve stem to be greater than the hardness of the diaphragm, the deformation requirement of the diaphragm can be met, and the valve stem can provide a certain support to the diaphragm, preventing excessive deformation of the diaphragm from affecting its sealing performance. At the same time, a valve stem with a certain degree of hardness can improve its own deformation resistance, so that the valve stem and valve core can move back and forth synchronously and stably. And through a valve stem with greater hardness, the valve stem diameter can be reduced to a certain extent, thereby reducing the volume of the entire three-way switching valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0044] Figure 1 This is a schematic diagram of the three-dimensional structure of the first embodiment of the present utility model.

[0045] Figure 2 for Figure 1 Schematic diagram of the side structure.

[0046] Figure 3 for Figure 2 Schematic diagram of the cut along section AA.

[0047] Figure 4 for Figure 3 Schematic diagram of the position of the valve stem and port.

[0048] Figure 5 for Figure 2 Schematic diagram of the cut along section BB.

[0049] Description of reference numerals:

[0050] 101. Valve chamber; 102. Liquid outlet channel; 103. Connecting channel; 104. Liquid inlet channel; 1041. Port; 105. Annular channel; 106. Connecting port; 107. Drive chamber; 1. Shell; 11. Upper shell; 12. Middle shell; 13. Lower shell; 131. Limiting protrusion; 14. Upper pressure plate; 15. Lower pressure plate; 2. Valve seat; 3. Diaphragm; 31. Outer edge; 32. Deformation portion; 33. Valve core; 330. First groove; 4. Drive assembly; 41. First drive assembly; 411. Spring; 412. Spring support seat; 4120. Second groove; 4121. Extension wall; 42. Second drive assembly; 421. Piston; 5. Valve stem; 6. Opposing portion; 7. Avoiding portion. DETAILED DESCRIPTION

[0051] The following is a clear and complete description of the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0052] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating positions or relationships, are based on the positions or relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0053] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0054] See also Figures 1 to 5 An embodiment of the utility model provides a three-way switching valve, including a shell 1, two valve seats 2, a diaphragm 3, a drive assembly 4 and a valve stem 5, wherein a valve cavity 101, a liquid outlet channel 102, a connecting channel 103 and a liquid inlet channel 104 are provided inside the shell 1.

[0055] Specifically, the housing 1 is provided with two valve chambers 101 and a liquid outlet channel 102 communicating with the two valve chambers 101. A communicating channel 103 is located between the two valve chambers 101, with valve seats 2 provided at both ends of the communicating channel 103, which are respectively communicated with the two valve chambers 101 through the two valve seats 2. A liquid inlet channel 104 is provided on the side of the communicating channel 103 and is communicated with the communicating channel 103. Two diaphragms 3 are respectively provided within the two valve chambers 101 and can abut against the valve seats 2 to seal the valve seats 2. At least one drive assembly 4 is provided, which is provided on the side of the diaphragm 3 away from the communicating channel 103 to control the movement of the diaphragm 3. A valve stem 5 is located within the communicating channel 103, with both ends of the valve stem 5 connected to the two diaphragms 3. The valve stem 5 can separate at least one diaphragm 3 from the valve seat 2, thereby placing the valve seat 2 in an open state.

[0056] The liquid inlet channel 104 has a port 1041 connected to the communication channel 103, with a vertical plane as the reference plane (such as Figure 2 AA plane in the figure), in projection on this reference plane, the central axis of the valve stem 5 is arranged to coincide with the center of the port 1041, wherein the port 1041 has a facing portion 6 opposite the valve stem 5 and avoidance portions 7 located on both sides of the facing portion 6. The arrangement of the avoidance portions 7 ensures that when fluid is introduced from the liquid inlet channel 104 provided on the side of the communicating channel 103, the fluid at the avoidance portions 7 will not directly flush the valve stem 5, thereby reducing the flushing force on the valve stem 5. At the same time, in this case, when the pressure of the fluid fluctuates, the change in the force acting on the valve stem 5 will also decrease, thereby reducing the change in pressure on the valve stem 5 and weakening the vibration of structures such as the valve body and the diaphragm 3.

[0057] Furthermore, let the total area of ​​the avoidance portion 7 be S1 ( Figure 3 The total area of ​​the facing portion 6 is S2, where S1 / S2 ≥ 0.3. Since the diameter of the facing portion 6 is positively correlated with the diameter of the valve stem 5, a reasonable ratio of the areas of the facing portion 6 and the relief portion 7 can not only reduce the forces acting on the valve stem 5 and the changes in these forces, thereby reducing vibration during use of the three-way valve, but also improve the valve stem 5's ability to resist deformation to a certain extent.

[0058] See also Figure 3 and Figure 4 In order to make the valve stem 5 more evenly stressed and avoid vibration of the valve stem 5 due to uneven stress, the two avoidance portions 7 are symmetrically arranged about the central axis of the valve stem 5.

[0059] See also Figure 5An annular flow channel 105 is formed between the outer wall of the valve stem 5 and the inner side of the connecting flow channel 103. The cross-sectional area of ​​the annular flow channel 105 is larger than the cross-sectional area of ​​the liquid inlet flow channel 104. By setting the cross-sectional area of ​​the annular flow channel 105 larger, the flow velocity of the fluid in the liquid inlet flow channel 104 will be slowed down after entering the annular flow channel 105, thereby making the flow of the fluid in the annular flow channel 105 more stable, and avoiding the strong turbulence in the annular flow channel 105 caused by the high fluid flow velocity, which would cause the valve stem 5 to vibrate.

[0060] See also Figure 5 The central axis L1 of the liquid inlet channel 104 is perpendicular to the central axis L2 of the valve stem 5, thereby preventing the liquid inlet channel 104 from tilting, which causes the impacted part of the valve stem 5 to be far away from the closed valve seat 2 when one of the diaphragms 3 is opened, causing the valve stem 5 to be easily deformed.

[0061] For the convenience of explanation, Figure 3 The lower end "upper side" under the middle position is Figure 3 The lower end of the center is referred to as the "lower side". Figure 3 The left side of the center is defined as "left side". Figure 3 The right side under the orientation is referred to as "right side".

[0062] See also Figures 1 to 3 In this embodiment, the housing 1 includes an upper housing 11, a middle housing 12, and a lower housing 13. The upper housing 11 and the lower housing 13 are respectively mounted on the two ends of the middle housing 12 and assembled to form the entire housing 1. The valve chamber 101, the liquid outlet channel 102, the connecting channel 103, and the liquid inlet channel 104 are all disposed on the middle housing 12. The valve seat 2 is also formed on the middle housing 12. An upper pressure plate 14 is also disposed between the upper housing 11 and the middle housing 12. One end of the upper pressure plate 14 abuts against the upper housing 11, and the other end presses the diaphragm 3 against the end of the middle housing 12, thereby forming a valve chamber 101 between the diaphragm 3 and the inner wall of the middle housing 12. Similarly, a lower pressure plate 15 is also disposed between the lower housing 13 and the middle housing 12. One end of the lower pressure plate 15 abuts against the lower housing 13, and the other end presses another diaphragm 3 against the end of the middle housing 12, thereby forming another valve chamber 101 between the diaphragm 3 and the inner wall of the middle housing 12.

[0063] It can be known that when the diaphragm 3 is in contact with the valve seat 2 on the corresponding side, the connecting flow channel 103 and the valve cavity 101 on the corresponding side will be separated by the valve seat 2 on the corresponding side (that is, the valve seat 2 on this side is sealed), and the fluid does not flow through the liquid outlet flow channel 102 on this side; when the diaphragm 3 is away from the valve seat 2 on the corresponding side, the connecting flow channel 103 is connected with the valve cavity 101 on the corresponding side through the valve seat 2 on this side, and the fluid flows out through the liquid outlet flow channel 102 on this side.

[0064] See also Figure 3The valve core 33 at the lower end abuts against the lower valve seat 2, while the valve core 33 at the upper end is separated from the upper valve seat 2. At this time, after passing through the connecting flow channel 103, the fluid flows from the upper valve cavity 101 to the liquid outlet flow channel 102 on the right, while the lower valve cavity 101 is blocked from the connecting flow channel 103.

[0065] Furthermore, the diaphragm 3 includes an outer edge portion 31, a deformation portion 32, and a valve core 33 that are integrally formed, wherein the outer edge portion 31 is sealed and fixed to the housing 12, the deformation portion 32 is located on the inner side of the outer edge portion 31, and the valve core 33 is located on the inner side of the deformation portion 32. When the valve core 33 moves, the deformation portion 32 will be deformed; the two ends of the valve stem 5 are respectively connected to the valve cores 33 in the two diaphragms 3. It can be seen that the diaphragm 3 is set to a structure of an outer edge portion 31, a deformation portion 32, and a valve core 33 that are integrally formed, wherein the outer edge portion 31 can maintain a stable seal with the housing 1, and the setting of the deformation portion 32 can prevent the reciprocating movement of the valve core 33 from affecting the sealing connection between the outer edge portion 31 and the housing 1. The valve core 33 is used to cooperate with the valve stem 5 so that the valve stem 5 can stably support the valve core 33, realize the reciprocating motion of the valve stem 5 and the valve core 33, and thereby enable the valve core 33 to maintain a tight seal with the valve seat 2, or enable the valve core 33 to maintain a separation with the valve seat 2 to conduct the corresponding flow channel.

[0066] Typically, to enhance the seal between the outer edge 31 of the diaphragm 3 and the housing 1, the valve core 33 and the valve seat 2 form an abutting seal. Furthermore, to prevent the reciprocating motion of the valve core 33 from affecting the seal between the outer edge 31 and the housing 1, the diaphragm 3 typically has a certain degree of deformation, which prevents the diaphragm 3 from having an excessively high hardness. The valve stem 5 is positioned between the two valve cores 33 to transmit axial pressure between the two diaphragms 3. If the valve stem and the diaphragms 3 were made of the same material, the strength of the valve stem 5 would be limited, making it susceptible to deformation. Alternatively, the diameter of the valve stem 5 would need to be increased to prevent deformation.

[0067] Therefore, to avoid this situation, in this embodiment, the valve stem 5 is harder than the diaphragm 3. This allows the valve stem 5 to provide some support for the diaphragm 3, preventing excessive deformation of the diaphragm 3 from affecting its sealing performance. Furthermore, the relatively hard valve stem 5 improves its deformation resistance, allowing the valve stem 5 and valve core 33 to reciprocate synchronously and stably. Furthermore, the harder valve stem 5 can reduce its diameter to a certain extent, thereby reducing the overall volume of the three-way switching valve.

[0068] When the fluid passes through the valve seat 2 , the fluid flow rate on the side close to the communication port 106 is faster, while the fluid flow rate on the other side is slower, which will cause uneven force on the valve stem 5 .

[0069] See also Figure 3 and Figure 5 In order to ensure that the forces acting on the valve stem 5 are opposite when different valve seats 2 are opened, so as to prevent the valve stem 5 from always being subjected to a force on one side, which may cause the valve stem 5 to be easily bent, in this embodiment, the liquid outlet channel 102 has a communication port 106 connected to the valve cavity 101. In the horizontal plane projection, the two communication ports 106 are respectively located on both sides of the valve stem 5 and are symmetrically arranged about the valve stem 5.

[0070] See also Figure 3 Two drive chambers 107 are provided inside the shell 1. The two drive chambers 107 are respectively located on the side of the two diaphragms 3 away from the valve chamber 101. Two drive components 4 are provided, namely the first drive component 41 and the second drive component 42. The first drive component 41 and the second drive component 42 are respectively located inside the two drive chambers 107.

[0071] It can be known that the upper shell 11, the upper pressure plate 14 and the upper diaphragm 3 form an upper driving chamber 107; the lower shell 13, the lower pressure plate 15 and the lower diaphragm 3 form a lower driving chamber 107.

[0072] Specifically, the first drive assembly 41 includes a spring 411 and a spring support seat 412. The two ends of the spring 411 are respectively against the inner wall of one of the drive chambers 107 and the spring support seat 412, and the spring support seat 412 is connected to one of the diaphragms 3. The second drive assembly 42 includes a piston 421. The piston 421 is sealed and slidably connected to the drive chamber 107 on the other side, and the piston 421 is connected to the other diaphragm 3. By respectively corresponding the first drive assembly 41 and the second drive assembly 42 to the diaphragms 3 on both sides, and the spring 411 of the first drive assembly 41 and the piston 421 of the second drive assembly 42 cooperate with each other, the two diaphragms 3 can be reciprocally driven when power is applied from one side (i.e., the piston 421 side), so that the two diaphragms 3 alternately abut against their corresponding valve seats 2, thereby achieving a simpler control process of the valve body and a simpler control of the flow conditions of each flow channel in the valve body.

[0073] In order to ensure the stability of the three-way valve operation and to avoid debris generated by friction between the structures when the diaphragm 3 and the valve stem 5 vibrate and swing (for example, when the diaphragm abuts the valve seat, vibration causes friction between the diaphragm and the valve seat to generate debris; or the diaphragm and the valve stem 5 move relative to each other to generate debris), the two ends of the valve stem 5 are radially limitedly connected to the two diaphragms 3.

[0074] See Figure 3Specifically, a first groove 330 is formed on the valve core 33 of the diaphragm 3, and the valve stem 5 is inserted into the first groove 330. The first groove 330 is configured as a circular groove, and the valve stem 5 is configured as a cylindrical rod. The diameter of the first groove 330 is equal to that of the valve stem 5. Of course, in other embodiments, the valve stem 5 can also be configured as a polygonal or square structure, etc., as long as the cross-sectional dimensions of the first groove 330 and the valve stem 5 are consistent.

[0075] Furthermore, when the diameter of the valve stem 5 is larger than the diameter of the first groove 330, an interference fit will form between the two, making installation difficult. During installation, friction between the two can easily generate debris, and the resulting resistance during assembly can easily cause deformation of the valve core 33 of the diaphragm 3. If the outer diameter of the valve stem 5 is smaller than the diameter of the first groove 330, the gap between the two can easily form a dead angle, causing impurities to accumulate and affecting the cleanliness of the fluid in the valve body. Therefore, in this embodiment, the diameter of the first groove 330 is equal to that of the valve stem 5. This not only facilitates installation and avoids debris generation, but also avoids the creation of dead angles. Furthermore, the valve stem 5 can also support the valve core 33, preventing deformation of the valve core 33.

[0076] See also Figure 3 In order to further ensure the stability of the three-way valve, the spring support seat 412 is connected to the side wall of the lower driving cavity 107 and the diaphragm 3 in a radial limiting manner to limit the swing of the diaphragm 3.

[0077] Specifically, the spring support seat 412 and the diaphragm 3 are connected in a radially limited manner via a first plug-in structure. The first plug-in structure includes a first plug-in slot and a first protrusion, wherein the first plug-in slot is formed at the upper end of the spring support seat 412, and the first protrusion is formed at the lower end of the diaphragm 3 (integrally formed). The first protrusion is inserted into the first plug-in slot. The dimensions of the first plug-in slot and the first protrusion can be consistent, or an interference fit can be used. Of course, in other embodiments, the first plug-in slot can also be formed at the lower end of the diaphragm 3. In this case, the first protrusion is provided at the upper end of the spring support seat 412, or the connection between the spring support seat and the diaphragm is achieved through a threaded structure.

[0078] Specifically, the spring support seat 412 and its corresponding drive cavity 107 (lower end drive cavity 107) are radially limited by a sliding connection. The spring support seat 412 has a downwardly extending extension wall 4121, which is radially limited by the extension wall 4121 and the side wall of the drive cavity 107. The height of the extension wall 4121 is greater than half the height of the drive cavity 107 in which it is located. The provision of the extension wall 4121 can increase the contact area between the spring support seat 412 and the drive cavity 107, thereby further improving the radial limiting effect of the spring support seat 412. In order to achieve both the limiting effect and reduce the friction between the spring support seat 412 and the drive cavity 107, the outer wall surface of the spring support seat 412 can be provided with a recessed groove.

[0079] See also Figure 3 At least two groups of springs 411 are provided, and different springs 411 have different natural frequencies, thereby avoiding resonance between the diaphragm 3 and the springs 411 .

[0080] Specifically, the two groups of springs 411 have different diameters and opposite rotation directions, and the central axes of the two groups of springs 411 coincide with each other.

[0081] In order to further ensure the stability of the spring 411, so that it applies a force along the central axis of the spring support seat 412, thereby ensuring that the spring support seat 412, the diaphragm 3 and the valve stem 5 move in the vertical direction, in this embodiment, the spring 411 and the spring support seat 412 are radially limited.

[0082] Specifically, a second groove 4120 is further provided at the lower end of the spring support seat 412. The second groove 4120 is configured as a stepped groove having two limiting sections of different diameters. The two limiting sections respectively abut against the outer wall surfaces of the two groups of springs 411 to achieve radial limiting settings of the two side walls of different diameters of the second groove 4120 and the two groups of springs 411, thereby limiting the two groups of springs 411 from tilting in the direction deviating from the center axis.

[0083] Furthermore, a limiting protrusion 131 is also provided on the lower shell 13, and the limiting protrusion 131 is against the inner wall of a group of springs 411 with smaller diameters or is located on the inner side of the springs 411 with smaller diameters, thereby further achieving a radial limiting effect on the springs 411.

[0084] See also Figure 3 In order to further ensure the stability of the three-way valve operation, the piston 421 is connected to the side wall of the other driving chamber 107 and the diaphragm 3 in a radial limiting manner to limit the swing of the diaphragm 3.

[0085] Specifically, the outer wall surface of the piston 421 slides with the side wall of the driving chamber 107 to limit the radial movement or swing of the piston 421 through the sliding connection, and further limit the radial swing of the diaphragm 3 connected thereto through the piston 421.

[0086] Furthermore, the piston 421 and the diaphragm 3 are connected by a second plug-in structure. Specifically, the second plug-in structure includes a second plug-in groove and a second protrusion. The second plug-in groove is provided at the lower end of the piston 421, and the second protrusion is provided at the upper end of the valve core 33. The second plug-in groove and the second protrusion can maintain consistent dimensions or adopt an interference fit. Of course, in other embodiments, the second plug-in groove can also be formed at the upper end of the diaphragm 3, in which case the second protrusion is provided at the lower end of the piston 421, or the connection between the two can be achieved through a threaded structure.

[0087] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and replacements made by technicians in this field on the basis of the present invention fall within the scope of protection required by the present invention.

Claims

1. A three-way switching valve, comprising: A housing, wherein two valve cavities and a liquid outlet channel communicating with the two valve cavities are provided inside the housing; A communication channel is located between the two valve chambers, with valve seats provided at both ends of the communication channel, and is connected to the two valve chambers through the two valve seats respectively; a liquid inlet channel, the liquid inlet channel being arranged on the side of the communication channel and being in communication with the communication channel; Two diaphragms are respectively arranged in the two valve cavities and can abut against the valve seat to seal the valve seat; There is at least one drive assembly, which is arranged on the side of the diaphragm away from the communicating flow channel to control the movement of the diaphragm; Characterized in that, the three-way switching valve further comprises: A valve stem is located inside the communication channel, with both ends of the valve stem connected to the two diaphragms respectively, and the valve stem can separate at least one diaphragm from the valve seat to open the valve seat; The liquid inlet channel has a port connected to the connecting channel. Taking a vertical plane as a reference plane, on the projection of the reference plane, the central axis of the valve stem and the center of the port are arranged to coincide with each other, wherein the port has a facing portion opposite to the valve stem and avoidance portions located on both sides of the facing portion. The total area of ​​the avoidance portion is S1, and the total area of ​​the facing portion is S2, wherein S1 / S2 ≥ 0.

3.

2. The three-way switching valve according to claim 1, characterized in that: In the projection of the reference plane, the two avoidance portions are symmetrically arranged about the central axis of the valve stem.

3. The three-way switching valve according to claim 1, characterized in that: An annular flow channel is formed between the outer wall of the valve stem and the inner side of the communicating flow channel, and the cross-sectional area of ​​the annular flow channel is larger than the cross-sectional area of ​​the liquid inlet flow channel.

4. The three-way switching valve according to claim 1, characterized in that: The diaphragm includes an outer edge portion on a sealed fixed housing, a deformable portion located inside the outer edge portion, and a valve core located inside the deformable portion. The outer edge portion, the deformable portion, and the valve core are integrally formed. When the valve core moves, the deformable portion will deform. Wherein, both ends of the valve stem are connected to the valve cores in the two diaphragms respectively, and the hardness of the valve stem is greater than the hardness of the diaphragm.

5. The three-way switching valve according to claim 1, characterized in that: The central axis of the liquid inlet channel is arranged perpendicular to the central axis of the valve stem.

6. The three-way switching valve according to claim 1, characterized in that: The liquid outlet channel has a communication port communicating with the valve cavity. In horizontal plane projection, the two communication ports are respectively located on both sides of the valve stem and are symmetrically arranged about the valve stem.

7. The three-way switching valve according to claim 1, characterized in that: Two drive cavities are provided inside the housing, and the two drive cavities are respectively located on the side of the two diaphragms away from the valve cavity. Two drive assemblies are provided, namely a first drive assembly and a second drive assembly, and the first drive assembly and the second drive assembly are respectively located inside the two drive cavities; The first driving assembly includes a spring and a spring support seat, wherein two ends of the spring respectively abut against one of the inner walls of the driving cavity and the spring support seat, and the spring support seat is connected to one of the diaphragms; The second driving assembly includes a piston, which is sealingly and slidingly connected to the driving chamber on the other side, and the piston is connected to another diaphragm.

8. The three-way switching valve according to claim 7, characterized in that: The two ends of the valve stem are connected to the two diaphragms in a radially limited manner; The spring support seat is connected to one of the drive chamber side walls and the diaphragm radially to limit the swing of the diaphragm, and / or the piston is connected to the other drive chamber side wall and the diaphragm radially to limit the swing of the diaphragm.

9. The three-way switching valve according to claim 8, characterized in that: The spring support seat has an extension wall extending downward and is radially limited by the extension wall and the side wall of the driving cavity. The height of the extension wall is greater than half the height of the driving cavity where the extension wall is located.

10. The three-way switching valve according to claim 7, characterized in that: The springs are provided in at least two groups, and different springs have different natural frequencies.

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