Two-way three-way valve
By designing a two-position three-way valve with a piston rod and elastic element, the problem of simultaneous connection of three air ports during the switching process in the existing technology is solved, achieving more efficient cylinder piston rod control, reducing air leakage, and improving the performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- DONGGUAN YIHEDA AUTOMATION CO LTD
- Filing Date
- 2023-09-07
- Publication Date
- 2026-06-30
AI Technical Summary
The existing two-position three-way valve is prone to having all three vent ports connected simultaneously when switching between the inlet and outlet, which can lead to air leakage and affect the extension and retraction of the cylinder piston rod.
Design a two-position three-way valve that uses the cooperation of piston rod and elastic element to achieve the closing and opening of piston in different positions, avoiding simultaneous connection of three inlets and outlets, and adopts drive mechanism and sealing element to improve sealing performance.
This effectively avoids the situation where all three inlets and outlets are connected simultaneously during the switching process, reducing air leakage and improving the performance of the cylinder piston rod.
Smart Images
Figure CN117267196B_ABST
Abstract
Description
Technical Field
[0001] This application relates, and particularly relates to, a two-position three-way valve. Background Technology
[0002] In related technologies, a shut-off two-position three-way valve includes a valve body and a valve core. The valve body has three air inlets, a, b, and c. The valve core moves back and forth between two positions within the valve body. When the valve core is in one position, it connects a and b; when the valve core moves to the other position, it connects a and c. However, when switching between the connected inlets and outlets, whether switching from a and b to a and c or vice versa, all three air inlets will always be connected simultaneously, leading to cross-contamination and affecting operation. For example, when the two-position three-way valve is used with a single-acting cylinder, if all three air inlets are connected during cylinder charging, air leakage will occur, affecting the extension and retraction of the cylinder piston rod, thus impacting the cylinder's performance. Summary of the Invention
[0003] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this application proposes a two-position three-way valve that can avoid the situation where all three inlets and outlets are simultaneously connected during the switching process from a state connecting the first and third inlets and outlets to a state connecting the first and second inlets and outlets.
[0004] According to a first aspect of the present invention, a two-position three-way valve includes: a valve body assembly, a piston, a piston rod, and a first elastic member. The valve body assembly includes a valve body, the sidewall of which is provided with a first inlet / outlet, a second inlet / outlet, and a third inlet / outlet. A boss surface is formed within the valve body on the side of the second inlet / outlet closer to the first inlet / outlet. The piston is hollow and open at both ends, and is slidably disposed within the valve body. The first end of the piston communicates with the third inlet / outlet. The piston rod is disposed within the valve body assembly along a first direction and is disposed towards the second end of the piston. At least a flow channel is formed between the outer periphery of the piston rod near the piston and the inner wall of the valve body, and the flow channel communicates with the first inlet / outlet. The piston rod can be positioned at a second position under the action of an external force. The piston rod slides between the first and second positions; a first elastic element is disposed between the piston and the valve body assembly; wherein, when the piston rod is in the first position, the piston rod opens the second end of the piston, the second end of the piston abuts against the boss surface, and the piston closes the second inlet and outlet, the first inlet and outlet, the flow channel, the piston and the third inlet and outlet are connected; when the piston rod is in the second position, the piston rod closes the second end of the piston, the second end of the piston disengages from the boss surface, and the second inlet and outlet, the flow channel and the first inlet and outlet are connected; during the process of the piston rod moving from the first position to the second position, before the piston rod closes the second end of the piston, the second end of the piston always abuts against the boss surface, and the piston disengages from the boss surface only after the piston rod 300 closes the second end of the piston 200.
[0005] The two-position three-way valve according to an embodiment of the present invention has at least the following beneficial effects: The two-position three-way valve includes a valve body assembly, a piston, a piston rod, and a first elastic element. The valve body assembly includes a valve body, and the side wall of the valve body is provided with a first inlet / outlet, a second inlet / outlet, and a third inlet / outlet. The three inlets / outlets are located at different positions in a first direction. The piston is slidably connected to the valve body, and the first end of the piston communicates with the third inlet / outlet. The piston rod is slidably connected to the valve body assembly, and at least a portion of the outer periphery of the piston near the piston forms a flow channel between it and the inner wall of the valve body. The flow channel communicates with the first inlet / outlet. The piston rod can slide between a second position and a first position under the action of an external force. When the piston rod is in the second position, the piston rod closes the second end of the piston, and the first elastic element located between the piston and the valve body undergoes elastic deformation, causing the piston to move away from the boss surface. The first inlet / outlet, the flow channel, and the second inlet / outlet are connected. As the piston rod moves from the second position to the first position under the action of an external force, the piston rod gradually moves away from the boss surface. The piston rod moves from the first position to the second position, opening the second end of the piston. Under the elastic force of the first elastic element, the piston approaches and abuts against the boss surface, thus closing the second inlet and outlet while simultaneously connecting the third inlet and outlet, the piston, the flow channel, and the first inlet and outlet. As the piston rod moves from the first position to the second position, it first abuts against the second end of the piston, closing it and disconnecting the first and third inlets and outlets. As the piston rod moves, the piston moves away from the boss surface, causing the first elastic element between the piston and the valve body to deform. This movement gradually opens the second inlet and outlet, connecting the second inlet and outlet, the flow channel, and the first inlet and outlet. Therefore, the piston rod in this application, by closing the piston and then opening the second inlet and outlet during its movement from the first position to the second position, avoids the situation where all three inlets and outlets are simultaneously connected during the transition from connecting the first and third inlets and outlets to connecting the first and second inlets and outlets.
[0006] According to some embodiments of the present invention, the two-position three-way valve further includes a drive mechanism connected to the piston rod and used to drive the piston rod to move between a second position and a first position.
[0007] According to some embodiments of the present invention, the driving mechanism includes a driving component and a second elastic element. The driving component is used to drive the piston rod to move from a first position to a second position, and the second elastic element is disposed between the piston rod and the valve body and is used to reset the piston rod from the second position to the first position.
[0008] According to some embodiments of the present invention, both the first elastic element and the second elastic element are springs, and the physical parameters and compression of the two springs satisfy the following: during the process of the piston rod moving from the second position to the first position, before the second end of the piston abuts against the boss, the piston rod always closes the second end of the piston; only after the second end of the piston abuts against the boss surface, the piston rod opens the second end of the piston under the elastic force of the second elastic element.
[0009] According to some embodiments of the present invention, the drive assembly includes a cam and a drive member. The drive assembly is disposed in the valve body. The output end of the drive member is connected to the cam and is used to drive the cam to rotate so that the outer contour surface of the cam can push the piston rod to move.
[0010] According to some embodiments of the present invention, the valve body assembly further includes a sleeve fixedly disposed within the valve body, and one end of the sleeve forms a boss surface, through which the piston rod passes.
[0011] According to some embodiments of the present invention, a first seal is provided at one end of the piston rod near the piston or at the second end of the piston. When the piston rod and the second end of the piston abut against each other, the first seal is located between the piston rod and the second end of the piston. A second seal is provided at the boss surface or at the second end of the piston. When the boss surface and the second end of the piston abut against each other, the second seal is located between the boss surface and the second end of the piston.
[0012] According to some embodiments of the present invention, a first seal is disposed at one end of the piston rod near the piston and in line contact with the second end of the piston; or, a first seal is disposed at the second end of the piston and in line contact with the end of the piston rod near the piston; a second seal is disposed on the boss surface and in line contact with the second end of the piston.
[0013] According to some embodiments of the present invention, at least one of the first seal and the second seal is a star-shaped sealing ring.
[0014] According to some embodiments of the present invention, a first retaining ring is also included. The first seal is disposed at the second end of the piston. The first retaining ring is disposed on the piston and located on the side of the first seal near the boss surface, so as to limit the first seal.
[0015] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description
[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:
[0017] Figure 1 This is a schematic diagram of the overall structure of one embodiment of the two-position three-way valve of the present invention;
[0018] Figure 2 for Figure 1 A schematic diagram of the two-position three-way valve shown from another perspective;
[0019] Figure 3 for Figure 2 A cross-sectional view AA of the two-position three-way valve shown in the figure;
[0020] Figure 4 for Figure 1 The diagram shows the structure of the actuator and cam in the two-position three-way valve.
[0021] Figure label:
[0022] Valve body assembly 100; valve body 110; first inlet / outlet 111; second inlet / outlet 112; third inlet / outlet 113; sleeve 120; boss surface 121; piston 200; piston rod 300; first elastic element 400; flow channel 500; first seal 600; second seal 700; second elastic element 800; cam 900; drive element 1000; first retaining ring 1100. Detailed Implementation
[0023] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.
[0024] In the description of this application, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.
[0025] In the description of this application, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.
[0026] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.
[0027] In the description of this application, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0028] The following is for reference. Figures 1 to 4 A two-position three-way valve according to an embodiment of the present invention is described.
[0029] like Figures 1 to 3 As shown, a two-position three-way valve according to an embodiment of the present invention includes: a valve body assembly 100, a piston 200, a piston rod 300, and a first elastic member 400; the valve body assembly 100 includes a valve body 110, the side wall of the valve body 110 is provided with a first inlet / outlet 111, a second inlet / outlet 112, and a third inlet / outlet 113, and a boss surface 121 is formed in the valve body 110 on the side of the second inlet / outlet 112 near the first inlet / outlet 111; the piston 200 is hollow and open at both ends, the piston 200 is slidably connected to the valve body 110 along a first direction, and the first end of the piston 200 communicates with the third inlet / outlet 113; the piston rod 300 is disposed in the valve body assembly 100 along the first direction and is disposed toward the second end of the piston, and at least a flow channel 500 is formed between the outer periphery of the piston rod 300 near the piston 200 and the inner wall of the valve body 110, the flow channel 500 communicates with the first inlet / outlet 111, and the piston rod 300 can be in a second position and a first position under the action of an external force. The piston slides between the piston 200 and the valve body assembly 100; a first elastic element 400 is disposed between the piston 200 and the valve body assembly 100, and is used to provide an elastic force for the piston to approach and abut against the boss surface; wherein, when the piston rod 300 is in the first position, the piston rod 300 opens the second end of the piston 200, the second end of the piston 200 abuts against the boss surface 121, and the side wall of the piston 200 closes the second inlet and outlet 112, and the first inlet and outlet 111, the flow channel 500, the piston 200 and the third inlet and outlet 113 are connected; when the piston rod 300 is in the second position, the piston rod 300 closes the second end of the piston 200, the second end of the piston 200 disengages from the boss surface 121, and the second inlet and outlet 112, the flow channel 500 and the first inlet and outlet 111 are connected; during the process of the piston rod moving from the first position to the second position, before the piston rod closes the second end of the piston, the second end of the piston always abuts against the boss surface, and only after the piston rod 300 closes the second end of the piston 200 does the piston disengage from the boss surface.
[0030] Understandably, this two-position three-way valve includes a valve body assembly 100, a piston 200, a piston rod 300, and a first elastic element 400. The valve body assembly 100 includes a valve body 110, the side wall of which is provided with a first inlet / outlet 111, a second inlet / outlet 112, and a third inlet / outlet 113, and the three inlets / outlets are located at different positions in a first direction. The piston 200 is slidably connected within the valve body 110, and the first end of the piston 200 communicates with the third inlet / outlet 113. The piston rod 300 is slidably connected within the valve body assembly 100, and the piston rod 300 forms a shape between at least a portion of its outer periphery near the piston 200 and the inner wall of the valve body 110. A flow channel 500 is formed, which is connected to the first inlet / outlet 111. The piston rod 300 can slide between a second position and a first position under the action of an external force. When the piston rod 300 is in the second position, the piston rod 300 closes the second end of the piston 200 and causes the first elastic element 400 located between the piston 200 and the valve body 110 to undergo elastic deformation. The piston 200 moves away from the boss surface 121, and the first inlet / outlet 111, the flow channel 500, and the second inlet / outlet 112 are connected. When the piston rod 300 moves from the second position to the first position under the action of an external force, the piston rod 300 gradually moves away from the second end of the piston 200, thereby opening the first inlet / outlet 111 of the piston 200. At both ends, the piston 200, under the elastic force of the first elastic element 400, approaches and abuts against the boss surface 121, thereby achieving the sealing of the second inlet / outlet 112 by the piston 200, while also connecting the third inlet / outlet 113, the piston 200, the flow channel 500, and the first inlet / outlet 111. During the movement of the piston rod 300 from the first position to the second position, the piston rod 300 first abuts against the second end of the piston 200, thereby sealing the piston 200 and cutting off the connection between the first inlet / outlet 111 and the third inlet / outlet 113. As the piston rod 300 moves, the piston 200 moves away from the boss surface 121, and the first elastic element 400 located between the piston 200 and the valve body 110... As the piston 200 deforms and moves away from the boss surface 121, the second inlet / outlet 112 is gradually opened, thus connecting the second inlet / outlet 112, the flow channel 500, and the first inlet / outlet 111. Therefore, in this application, the piston rod 300, during its movement from the first position to the second position, first closes the piston 200 and then opens the second inlet / outlet 112, avoiding the situation where all three inlets / outlets are connected simultaneously during the transition from the state connecting the first inlet / outlet 111 and the third inlet / outlet 113 to the state connecting the first inlet / outlet 111 and the second inlet / outlet 112. In this way, when used with a single-acting cylinder, the degree of air leakage is reduced.
[0031] Understandably, the two-position three-way valve also includes an actuation mechanism connected to the piston rod 300 and used to drive the piston rod 300 between the second position and the first position. For example, as... Figures 1 to 3As shown, in this embodiment, the piston rod 300 can move between the second position and the first position through the drive mechanism.
[0032] It is understood that the drive mechanism includes a drive assembly and a second elastic element 800. The drive assembly drives the piston rod 300 to move from a first position to a second position. The second elastic element 800 is disposed between the piston rod 300 and the valve body 110 and is used to reset the piston rod 300 from the second position to the first position. For example, as... Figures 1 to 3 As shown, in this embodiment, the driving mechanism includes a driving component and a second elastic element 800. The piston rod 300 can move from a first position to a second position under the drive of the driving component, and can move from the second position to the first position under the action of the second elastic element 800.
[0033] It should be understood that, in addition to the aforementioned configuration of the drive assembly and the second elastic element 800, in some other embodiments, the drive mechanism may also consist solely of the drive assembly, such as a double-acting cylinder connected to the piston rod 300. The piston rod 300 is connected to the output end of the double-acting cylinder, thereby enabling the piston rod 300 to switch between the second position and the first position. In other embodiments, the piston rod 300 may be configured as a screw, driven by a motor to rotate, thereby moving between the second position and the first position.
[0034] It is understandable that both the first elastic element 400 and the second elastic element 800 are springs, and the physical parameters and compression of the two springs satisfy the following: during the movement of the piston rod 300 from the second position to the first position, before the second end of the piston abuts against the boss, the piston rod always closes the second end of the piston; only after the second end of the piston 200 abuts against the boss surface does the piston rod 300 open the second end of the piston 200 under the elastic force of the second elastic element. For example, as... Figures 1 to 3As shown, in this embodiment, the physical parameters and compression amount of the first elastic element 400 and the second elastic element 800 are such that during the process of the piston rod 300 moving from the second position to the first position, the piston rod 300 opens the second end of the piston 200 only after the second end of the piston 200 abuts against the boss surface 121. That is to say, during the process of the piston 200 approaching the boss surface 121, the piston rod 300 always closes the second end of the piston 200. That is, before the piston 200 abuts against the boss surface 121 (before the piston 200 closes the second inlet / outlet 112), only the first inlet / outlet 111 and the second inlet / outlet 112 are connected. After the piston 200 abuts against the boss surface 121 (after the piston 200 closes the second inlet / outlet 112), the piston rod 300 opens the piston 200 under the action of the second elastic element 800, realizing the connection between the first inlet / outlet 111 and the third inlet / outlet 113. Therefore, this solution not only prevents the three inlets and outlets from being connected simultaneously during the switching process from the first and third connected inlets and outlets to the first and second connected inlets and outlets, but also prevents the three inlets and outlets from being connected simultaneously during the switching process from the first and second connected inlets and outlets to the first and third connected inlets and outlets. Thus, the solution ensures that the three inlets and outlets will never be connected during the entire switching process.
[0035] The physical parameters here include, but are not limited to, stiffness coefficient and length. The compression amount and stiffness coefficient together determine the elastic force of the corresponding elastic element. In short, the first elastic element 400 and the second elastic element 800 can ensure that the piston rod 300 does not detach from the second end of the piston 200 during the process of the piston 200 abutting against the boss surface 121.
[0036] It should be understood that the first elastic element 400 may be a compression spring disposed at the end of the piston 200 away from the boss surface 121, or a tension spring disposed at the end of the piston 200 near the boss surface 121; the second elastic element 800 may be a compression spring passing through the piston 200 and located at the end of the piston rod 300 near the piston 200, or a tension spring disposed at the end of the piston rod 300 away from the piston 200.
[0037] It is understood that the drive assembly includes a cam 900 and a drive member 1000. The drive assembly is located in the valve body 110. The output end of the drive member 1000 is connected to the cam 900 and is used to drive the cam 900 to rotate, so that the outer contour surface of the cam 900 can push the piston rod 300 to move. For example, as Figure 4As shown, in this embodiment, the drive assembly includes a drive member 1000 and a cam 900 connected to each other. Under the drive of the drive member 1000, the cam 900 rotates, so that the protruding part of the outer contour surface of the cam 900 gradually turns towards the piston rod 300 and abuts against the piston rod 300, thereby enabling the piston rod 300 to move from the first position to the second position.
[0038] Specifically, the driving component 1000 can be a handwheel, which is fixed to the cam 900, so that the cam 900 can be driven to rotate by rotating the handwheel.
[0039] Understandably, the valve body assembly 100 also includes a sleeve 120, which is fixed within the valve body 110, and one end of the sleeve 120 forms a boss surface 121, through which the piston rod 300 passes. For example, as Figure 3 As shown, in this embodiment, the valve body assembly 100 further includes a sleeve 120, which is disposed inside the valve body 110, and the boss surface 121 is one end face of the sleeve 120, and the piston rod 300 passes through the sleeve 120.
[0040] It should be understood that, in addition to the above embodiment where the boss surface 121 is one end face of the sleeve 120, in some other embodiments, the boss surface 121 may also be part of the valve body 110, which is a raised edge formed along the inner peripheral wall of the valve body 110.
[0041] It is understood that a first seal 600 is provided at one end of the piston rod 300 near the piston 200 or at the second end of the piston 200. When the piston rod and the second end of the piston abut, the first seal is located between the piston rod and the second end of the piston. A second seal 700 is provided at the boss surface 121 or at the second end of the piston 200. When the boss surface and the second end of the piston abut, the second seal is located between the boss surface and the second end of the piston. For example, as... Figure 3 As shown, in this embodiment, a first sealing element 600 is provided at one end of the piston rod 300 near the piston 200 or at one end of the piston 200 near the piston rod 300, thereby improving the sealing of the piston 200 when the first inlet / outlet 111 is connected to the second inlet / outlet 112; a second sealing element 700 is provided at the boss surface 121 or at the second end of the piston 200, thereby improving the sealing of the second inlet / outlet 112 when the first inlet / outlet 111 is connected to the third inlet / outlet 113.
[0042] It is understood that the first seal 600 is located at the end of the piston rod 300 near the piston 200 and in line contact with the second end of the piston 200; or, the first seal 600 is located at the second end of the piston 200 and in line contact with the end of the piston rod 300 near the piston 200; the second seal 700 is located on the boss surface 121 and in line contact with the second end of the piston 200. For example, as... Figure 3 As shown, in this embodiment, the sealing area is reduced by using line contact, thereby increasing the pressure under the same pressure and thus improving the sealing performance.
[0043] It is understandable that at least one of the first and second seals is a star-shaped seal ring. For example, as... Figure 3 As shown, in this embodiment, by setting the first and second seals in the form of star-shaped sealing rings, the use of standard parts improves the versatility of the parts used, reduces costs, and facilitates procurement.
[0044] It is understood that it also includes a first retaining ring 1100, and a first seal 600 is disposed at the second end of the piston 200. The first retaining ring 1100 is disposed on the piston 200 and located on the side of the first seal 600 near the boss surface 121, to limit the first seal 600. For example, as Figure 3 As shown, in this embodiment, a first retaining ring 1100 is also included. The first retaining ring 1100 can limit the first seal 600, avoiding the problem that the first seal 600 is not easy to replace due to the vulcanization process, thereby making the first seal 600 easier to disassemble.
[0045] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application. Furthermore, unless otherwise specified, the embodiments and features described in the embodiments of this application can be combined with each other.
Claims
1. A two-position three-way valve, characterized in that, include: The valve body assembly (100) includes a valve body (110), the side wall of which is provided with a first inlet and outlet (111), a second inlet and outlet (112) and a third inlet and outlet (113), and a boss surface (121) is formed in the valve body (110) on the side of the second inlet and outlet (112) near the first inlet and outlet (111). The piston (200) is hollow and open at both ends. The piston (200) can be slidably connected to the valve body (110) along the first direction. The first end of the piston (200) is connected to the third inlet and outlet (113). A piston rod (300) is disposed within the valve body assembly (100) along the first direction and facing the second end of the piston. At least a portion of the outer periphery of the piston rod (300) near the piston (200) is formed between the piston rod (300) and the inner wall of the valve body (110). The flow channel (500) communicates with the first inlet and outlet (111). The piston rod (300) can slide between a first position and a second position under the action of an external force. A first elastic element (400) is disposed between the piston (200) and the valve body assembly (100), and is used to provide an elastic force for the piston (200) to move closer to and abut against the boss surface; wherein, When the piston rod is in the first position, the piston rod (300) opens the second end of the piston (200), the second end of the piston (200) abuts against the boss surface (121), and the side wall of the piston (200) closes the second inlet and outlet (112). The first inlet and outlet (111), the flow channel (500), the piston (200) and the third inlet and outlet (113) are connected. When the piston rod is in the second position, the piston rod (300) closes the second end of the piston (200), the second end of the piston (200) is disengaged from the boss surface (121), and the second inlet / outlet (112) and the flow channel (500) are connected to the first inlet / outlet (111); During the process of the piston rod moving from the first position to the second position, the second end of the piston always abuts against the boss surface before the piston rod closes the second end of the piston. Only after the piston rod (300) closes the second end of the piston (200) does the piston disengage from the boss surface.
2. The two-position three-way valve according to claim 1, characterized in that, The two-position three-way valve also includes a drive mechanism connected to the piston rod (300) and used to drive the piston rod (300) to move between the second position and the first position.
3. The two-position three-way valve according to claim 2, characterized in that, The driving mechanism includes a driving component and a second elastic element (800). The driving component is used to drive the piston rod (300) to move from the first position to the second position. The second elastic element (800) is disposed between the piston rod (300) and the valve body (110) and is used to move the piston rod (300) from the second position to the first position.
4. The two-position three-way valve according to claim 3, characterized in that, Both the first elastic element (400) and the second elastic element (800) are springs, and the physical parameters and compression of the two springs satisfy the following: during the process of the piston rod (300) moving from the second position to the first position, before the second end of the piston abuts against the boss, the piston rod always closes the second end of the piston. Only after the second end of the piston (200) abuts against the boss surface (121) does the piston rod (300) open the second end of the piston (200) under the action of the second elastic element (800).
5. The two-position three-way valve according to claim 3, characterized in that, The drive assembly includes a cam (900) and a drive member (1000). The drive assembly is located on the valve body (110). The output end of the drive member (1000) is connected to the cam (900) and is used to drive the cam (900) to rotate so that the outer contour surface of the cam (900) can push the piston rod (300) to move.
6. The two-position three-way valve according to claim 1, characterized in that, The valve body assembly (100) further includes a sleeve (120), which is fixed inside the valve body (110), and one end of the sleeve (120) forms the boss surface (121), and the piston rod (300) passes through the sleeve (120).
7. The two-position three-way valve according to claim 1, characterized in that, The piston rod (300) is provided with a first seal (600) at one end near the piston (200) or at the second end of the piston (200). When the piston rod and the second end of the piston abut, the first seal is located between the piston rod and the second end of the piston. The boss surface (121) or the second end of the piston (200) is provided with a second seal (700). When the boss surface and the second end of the piston abut, the second seal is located between the boss surface and the second end of the piston.
8. The two-position three-way valve according to claim 7, characterized in that, The first seal (600) is disposed at one end of the piston rod (300) near the piston (200) and in line contact with the second end of the piston (200); or, the first seal (600) is disposed at the second end of the piston (200) and in line contact with one end of the piston rod (300) near the piston (200). The second seal (700) is disposed on the boss surface (121) and contacts the second end line of the piston (200).
9. The two-position three-way valve according to claim 7, characterized in that, At least one of the first seal and the second seal is a star-shaped sealing ring.
10. The two-position three-way valve according to claim 9, characterized in that, It also includes a first retaining ring (1100), the first seal (600) is disposed at the second end of the piston (200), the first retaining ring (1100) is disposed on the piston (200) and located on the side of the first seal (600) near the boss surface (121) to limit the first seal (600).