Electromagnetic valve

Abstract

The invention provides an electromagnetic valve which comprises a valve body and a piston, a valve port is formed in the electromagnetic valve, and the piston can move in the axial direction of the electromagnetic valve to block or open the valve port. The electromagnetic valve further comprises a first sealing component, the first sealing component is arranged between the valve body and the piston in the radial direction of the electromagnetic valve, the outer side wall of the piston comprises a first wall part and a second wall part, and the second wall part is closer to the valve port relative to the first wall part in the axial direction of the electromagnetic valve. In the valve closing state, the first wall portion abuts against the first sealing component, in the valve opening state, the first wall portion does not make contact with the first sealing component, and a radial gap along the electromagnetic valve is formed between the second wall portion and the first sealing component. The electromagnetic valve is beneficial to improving the friction force problem in the operation process of the piston.

Description

Technical Field

[0001] The present invention relates to the field of valve technology, and in particular to a solenoid valve. Background Art

[0002] The solenoid valve includes a valve body and a piston. The piston can move along the valve cavity of the valve body to block or open the valve port on the valve body. A piston sealing ring is arranged between the piston and the inner surface of the valve body. The piston and the valve body are slidably sealed by the piston sealing ring. However, the sliding contact between the piston and the piston sealing ring will generate friction. In this way, when the piston moves axially to close the valve, due to the existence of friction, the restoring force of the spring may be difficult to overcome the friction, resulting in loose valve closure. Summary of the invention

[0003] The purpose of the present application is to provide a solenoid valve, which is helpful to improve the friction during the operation of the piston.

[0004] The present application provides a solenoid valve, comprising a valve body and a piston, wherein the solenoid valve is provided with a valve port, and the piston can move along the axial direction of the solenoid valve to block or open the valve port; the solenoid valve also includes a first sealing component, wherein the first sealing component is arranged between the valve body and the piston along the radial direction of the solenoid valve, and the outer side wall of the piston includes a first wall portion and a second wall portion, and along the axial direction of the solenoid valve, the second wall portion is closer to the valve port than the first wall portion; in a closed valve state, the first wall portion and the first sealing component are in contact, and in an open valve state, the first wall portion and the first sealing component are not in contact, and there is a radial gap between the second wall portion and the first sealing component along the solenoid valve.

[0005] In the solenoid valve of the present application, the first sealing component contacts the outer wall of the piston when the valve is closed to prevent leakage between the valve body and the piston. In the valve open state, the first sealing component does not contact the outer wall of the piston and no friction is generated. Therefore, the setting method of the solenoid valve in the present application can take into account the needs of valve closing sealing and reducing valve opening resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 A schematic diagram of a solenoid valve in an embodiment of the present application;

[0007] Figure 2 for Figure 1 The main view of

[0008] Figure 3 for Figure 2 AA section view of the electric valve;

[0009] Figure 4 for Figure 1 Exploded diagram of

[0010] Figure 5 for Figure 4 Schematic diagram from another perspective;

[0011] Figure 6 for Figure 3 Enlarged view of the B area;

[0012] Figure 7 for Figure 6 A schematic diagram of a first sealing component;

[0013] Figure 8 for Figure 6 Schematic diagram of the structure of the middle piston;

[0014] Fig. 9 for Figure 8 Schematic diagram of the three-dimensional structure of the middle piston;

[0015] Fig.10 for Fig. 9 Schematic diagram of another perspective of the middle piston;

[0016] Fig.11 for Figure 3 The schematic diagram of the solenoid valve in the middle is in the open state;

[0017] Fig.12 for Fig.11 Enlarged view of the middle C area;

[0018] Fig.13 for Figure 3 Schematic diagram of the structure of the middle moving iron core.

[0019] Figure 1-13 The reference numerals in the drawings are described as follows:

[0020] 1-static iron core; 2-magnetic plate; 2a-top wall; 2b-bottom wall; 3-coil structure; 3a-connecting part; 3b-axial through hole;

[0021] 4-moving iron core; 4a-balancing hole; 4a1-axial hole section; 4a2-radial hole section; 4b-connecting piece; 4c-iron core step surface;

[0022] 5- Spring;

[0023] 6-piston; 6a-annular groove; 6a1-first wall portion; 6a2-second wall portion; 6b-connecting hole; 6c-annular sealing portion; 6d-cover portion; 6e-cylindrical portion; 6f-groove;

[0024] 7-valve body; 71-first valve body; 71a-first step portion; 71a1-first step surface; 71a2-first step side wall; 72-second valve body; 72a-inlet; 72c-upper end surface; 72b-second step surface; 73-third valve body; 73a-outlet; 73b-valve port portion; 73b1-valve port;

[0025] 8-first sealing component; 8a-sealing outer ring; 8b-sealing inner ring;

[0026] 9- fourth sealing component; 10- second sealing component; 11- third sealing component. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0028] Please refer to Figure 1-5 , Figure 1 A schematic diagram of a solenoid valve in an embodiment of the present application; Figure 2 for Figure 1 The main view of Figure 3 for Figure 2 AA section view of the electric valve; Figure 4 for Figure 1 Exploded diagram of Figure 5 for Figure 4 Schematic diagram from another perspective.

[0029] In this embodiment, the solenoid valve includes a coil structure 3, a magnetic plate 2, a moving iron core 4, and a static iron core 1. The magnetic plate 2 is an annular frame structure, including a top wall 2a, a bottom wall 2b, and two side walls. The main part of the coil structure 3 is located between the top wall 2a and the bottom wall 2b of the magnetic plate 2. The coil structure 3 has an axial through hole 3b that passes through the axial direction thereof. At least part of the static iron core 1 is located in the axial through hole 3b. Figure 3 As shown, the static iron core 1 is fixed in the axial through hole 3b of the coil structure 3, for example, it can be press-fitted and fixed to the coil structure 3. Of course, it can also be fastened to the coil structure 3 by fasteners, or fixed as an insert by injection molding, etc. The specific connection method is not limited. At least part of the moving iron core 4 is also located in the axial through hole 3b of the coil structure 3, and can slide along the axial through hole 3b. A spring 5 is also provided between the moving iron core 4 and the static iron core 1. The coil structure 3 also has a connecting portion 3a, which extends axially from the side of the main part of the coil structure 3 and is used to establish an electrical connection with the outside. After the coil structure 3 is energized, the moving iron core 4 can generate a magnetic attraction, so that the moving iron core 4 moves toward the static iron core 1, and then compresses the spring 5. After the coil structure 3 is powered off, the moving iron core 4 loses its magnetic attraction, and the moving iron core 4 moves axially away from the static iron core 1 under the elastic restoring force of the spring 5. Figure 3When the perspective is working, after the moving iron core 4 loses its magnetic attraction, the gravity of the moving iron core 4 and the restoring force of the spring 5 together push the moving iron core 4 away from the static iron core 1.

[0030] The solenoid valve in this embodiment also includes a valve body and a piston 6. The valve body 7 has a valve cavity and is formed with a valve port 73b. The valve port 73b has a valve port 73b1. The piston 6 is connected to the moving iron core 4 so that it moves along the axial direction of the solenoid valve in the valve cavity of the valve body 7 under the drive of the moving iron core 4, thereby opening or blocking the valve port 73b1. The axial and radial directions of the solenoid valve are also the axial and radial directions of the piston 6. Figure 3 As shown, the valve body 7 specifically includes a first valve body 71, a second valve body 72 and a third valve body 73 distributed along the axial direction, wherein the first valve body 71 is closest to the coil structure 3, and then connected to the second valve body 72 and the third valve body 73 in sequence, and the first valve body 71, the second valve body 72 and the third valve body 73 are all roughly cylindrical structures.

[0031] Please continue to refer to Figure 6-10 , Figure 6 for Figure 3 Enlarged view of the B area; Figure 7 for Figure 6 A schematic diagram of the first sealing component 8; Figure 8 for Figure 6 A schematic structural diagram of the middle piston 6; Fig. 9 for Figure 8 A schematic diagram of the three-dimensional structure of the middle piston 6; Fig.10 for Fig. 9 A schematic diagram of the piston 6 from another perspective.

[0032] As mentioned above, the piston 6 will move axially under the drive of the moving iron core 4 to approach or move away from the valve port 73b1 of the valve port portion 73b. Figure 3 As shown, the axial direction is defined as the up-down direction in this article, the coil structure 3 is located on the upper side, and the valve body 7 is located on the lower side. The piston 6 moves axially relative to the valve body 7, and the piston 6 and the valve body 7 need to be sealed when the valve is closed to prevent leakage. Specifically in this embodiment, the solenoid valve includes an annular first sealing component 8, and the first sealing component 8 is used to achieve the sealing cooperation between the piston 6 and the valve body 7. Figure 8 , 9 As shown, the outer wall of the piston 6 includes an annular first wall portion 6a1, which is specifically an annular inclined surface. The inclined surface is inclined relative to the axial direction. Specifically, the inclined surface gradually inclines toward the middle of the piston 6 in the direction close to the valve port 73b1, that is, from top to bottom, gradually inclines toward the middle of the piston 6. In this way, Figure 6 As shown in FIG. 1 , when the piston 6 blocks the valve port 73b1 and the solenoid valve is in a closed state, the first wall portion 6a1 of the piston 6 and the first sealing component 8 abut against each other to achieve sealing. Specifically, the cross section of the first sealing component 8 in this embodiment is Figure 6The first sealing component 8 and the first wall portion 6a1 of the piston 6 are in line contact, which can ensure the abutting pressure and sealing effect. It can be seen that the line contact here does not limit the formation of an annular sealing line after the sealing crimping. Obviously, a certain deformation will occur during the abutment, and the first sealing component 8 and the piston 6 can form a relatively narrow annular sealing surface after the abutment. It can be understood that the first sealing component 8 is not limited to a circular cross-section, and can also be other shapes, such as an ellipse, a square, etc., as long as it forms an abutment with the first wall portion 6a1 when the valve is closed to achieve sealing.

[0033] Look again Fig.11 , 12 , Fig.11 for Figure 3 The schematic diagram of the solenoid valve in the middle is in the open state; Fig.12 for Fig.11 Magnified view of area C in the middle.

[0034] When the piston 6 moves axially upward toward the static iron core 1, the first wall portion 6a1 of the piston 6 will no longer contact the first sealing component 8, and the outer wall of the piston 6 also includes an annular second wall portion 6a2, and the second wall portion 6a2 is closer to the valve mouth portion 73b relative to the first wall portion 6a1, that is, the second wall portion 6a2 is located below the first wall portion 6a1, and the first wall portion 6a1 and the second wall portion 6a2 are connected axially. The second wall portion 6a2 is specifically a straight cylindrical wall portion of equal diameter in this embodiment, and the radial dimension of the second wall portion 6a2 is equal to the inner diameter of the first wall portion 6a1. The second wall portion 6a2 and the first sealing component 8 have a radial gap along the radial direction of the solenoid valve, that is, the second wall portion The diameter of 6a2 is smaller than the inner diameter of the first sealing component 8. In this way, when the piston 6 moves upward, the first wall portion 6a1 is separated from the first sealing component 8, and there is a radial gap between the second wall portion 6a2 and the first sealing component 8. Therefore, during the valve opening process, once the first wall portion 6a1 and the first sealing component 8 are no longer in contact, the outer wall of the piston 6 will always maintain a radial spacing with the first sealing component 8, and the second wall portion 6a2 will never contact or rub against the first sealing component 8. Therefore, during the valve opening process, the first sealing component 8 will not form a resistance to valve opening. Similarly, during the valve closing process, the second wall portion 6a2 will never contact or rub against the first sealing component 8, and will not form a resistance to valve closing.

[0035] It can be seen that the second wall portion 6a2 is not limited to being a uniform diameter wall portion, and can also be designed with non-uniform diameters, as long as there is a radial spacing with the first sealing component 8. In this case, the maximum diameter of the second wall portion 6a2 can be smaller than the minimum diameter of the first sealing component 8.

[0036] That is to say, the first sealing component 8 of the solenoid valve in this embodiment is sealed with the outer wall of the piston 6 only when the valve is closed, and in the valve open state (at any opening except the valve closed state), the first sealing component 8 has no contact with the outer wall of the piston 6. In fact, except for the valve closed state, there is no need to seal between the inner wall of the valve body 8 and the outer wall of the piston 6 in the valve open state. Therefore, the setting method in this embodiment can take into account the needs of valve closing sealing and reducing valve opening resistance.

[0037] It can be seen that the height of the second wall portion 6a2 is not less than the stroke of the piston 6, so as to ensure that during the valve opening process, the second wall portion 6a2 and the first sealing component 8 are always opposite in the radial direction to maintain a radial gap. In addition, the first wall portion 6a1 is an inclined surface to form a line contact with the first sealing component 8, and when abutting the seal, abutment in the radial and axial directions is formed at the same time to ensure the sealing effect, but the first wall portion 6a1 can also be other structural forms, and can also form an annular surface seal with the first sealing component 8, such as the first wall portion 6a1 is a downward plane, horizontal to the radial direction, and directly presses on the first sealing component 8 along the axial direction; the first sealing component 8 and the first wall portion 6a1 can also be a surface contact seal, as long as they abut and seal when closing the valve and separate from each other when opening the valve, they are all within the protection scope of this embodiment.

[0038] In detail, the first sealing component 8 in this embodiment is a component structure, such as Figure 7 As shown, the first sealing component 8 includes an annular sealing inner ring 8b and a sealing outer ring 8a coated on the outside of the sealing inner ring 8b, that is, the sealing outer ring 8a is an annular tubular structure, and the sealing inner ring 8b and the sealing outer ring 8a are both made of elastic materials. The sealing inner ring 8b is made of rubber material, and the sealing outer ring 8a can be made of PTFE (Polytetrafluoroethylene, polytetrafluoroethylene) material. PTFE material has excellent chemical compatibility, which can isolate the external working medium and the sealing inner ring 8b made of rubber material from chemical reaction, reduce the risk of swelling, and at the same time, the good elasticity of the rubber material can be used to ensure the reliability of the seal. It can be seen that the component-type first sealing component 8 in this embodiment has both chemical stability and good elastic sealing function.

[0039] like Figure 8 As shown, the piston 6 in this embodiment includes a cylindrical portion 6e and a cover portion 6d. The cylindrical portion 6e is a straight cylinder, and the cover portion 6d is covered on the top of the cylindrical portion 6e. The cover portion 6d and the cylindrical portion 6e can be Figure 8The one-piece structure shown in the figure may also be a split structure. In order to facilitate the formation of the above-mentioned inclined first wall portion 6a1, an annular groove 6a may be processed on the outer wall of the cylindrical portion 6e. The first groove side wall of the annular groove 6a close to the moving iron core 4 and away from the valve port 73b1 forms the first wall portion 6a1, that is, the first groove side wall on the upper side of the annular groove 6a is the first wall portion 6a1, and the bottom wall of the annular groove 6a opposite to its groove forms the second wall portion 6a2. At this time, the annular groove 6a also includes a second groove side wall close to the valve port 73b1. The first groove side wall and the second groove side wall are arranged opposite to each other in the axial direction of the solenoid valve. Obviously, the second groove side wall does not contact the first sealing component 8 during the valve opening process.

[0040] It can be known that the first wall portion 6a1 is not limited to being formed in this way, and the outer wall of the cylinder of the piston 6 may also be provided with an annular radial flange, and the wall portion of the radial flange facing the valve port portion 73b is an inclined surface, which can also form the required first wall portion 6a1. In this embodiment, the method of machining the annular groove 6a on the outer wall of the cylinder portion 6e of the piston 6 to form the first wall portion 6a1 and the second wall portion 6a2 is relatively simple.

[0041] In addition, in the present embodiment, at least one of the first valve body 71 and the second valve body 72 may be provided with a guide portion, and the guide portion is used to guide the piston 6. In the present embodiment, both the first valve body 71 and the second valve body 72 are provided with guide portions, and the guide portion provided for the first valve body 71 is defined as the first guide portion, and the guide portion provided for the second valve body 72 is defined as the second guide portion, wherein the first guide portion is located above the first sealing component 8, and the second guide portion of the second valve body 72 is located below the first sealing component 8. The first guide portion may specifically be at least a portion of the inner wall of the first valve body 71, and the second guide portion may specifically be at least a portion of the inner wall of the second valve body 72.

[0042] Look again Figure 3 , and combined with Fig.13 understand, Fig.13 for Figure 3 Schematic diagram of the structure of the middle moving iron core 4.

[0043] In this embodiment, the moving iron core 4 and the piston 6 of the solenoid valve are directly connected. A connecting hole 6b can be provided on the piston 6. A connecting piece 4b is provided at one end of the moving iron core 4 facing the piston 6. The connecting piece 4b can be a protrusion provided at the lower end of the moving iron core 4. The connecting piece 4b can be inserted into the connecting hole 6b for connection and fixation. Specifically, the connecting piece 4b and the connecting hole 6b can be fixed by riveting, that is, the connecting piece 4b is inserted into the connecting hole 6b and then riveted. Fig.13 The connector 4b shown in the figure is the shape after riveting. The lower end of the connector 4b is expanded. Before riveting, the connector 4b can be a constant diameter structure. After riveting, it presents Figure 8The structure shown in the figure cannot be separated from the piston 6 in the axial direction. This riveting connection is relatively simple and reliable. Of course, the connecting member 4b and the piston 6 can also be connected by fasteners or press-fit connection. It can be seen that the piston 6 in this embodiment is directly connected to the moving iron core 4, and the moving iron core 4 directly drives the piston 6 to reciprocate in the axial direction. The structure is simple and reliable, and the number of parts is small.

[0044] At this time, a balancing hole 4a can also be opened on the moving iron core 4. The balancing hole 4a includes a radial hole section 4a2 and an axial hole section 4a1. The axial hole section 4a1 passes through the moving iron core 4. The connecting piece 4b passes through the connecting hole 6b on the piston 6. The piston 6 in this embodiment is a shell-like structure with an opening at the bottom. The bottom of the piston 6 is facing the side of the valve mouth 73b. In this way, the axial hole section 4a1 of the balancing hole 4a is connected to the inner cavity of the piston 6. The working medium in the inner cavity of the piston 6 can enter the space above the moving iron core 4 from the axial hole section 4a1, and can reach the space above the top of the piston 6 from the radial hole section 4a2. The top of the piston 6 is the side of the piston 6 away from the valve mouth 73b. Fig.13 As shown, the axial hole section 4a1 has an upper hole 4a11 with a larger aperture. The upper hole 4a11 has a larger aperture, forming an iron core step surface 4c. The upper hole 4a11 can be used as a spring chamber of the spring 5, and one end of the spring 5 can abut against the iron core step surface 4a11. The piston 6 in this embodiment is a shell-like structure with an opening downward, and the space above the top is small. Even if the piston 6 opens upward during shipment or other working conditions, the space above the piston 6 is not easy to accumulate system lubricating grease. In this way, when the solenoid valve is started to open or close the valve, it is not easy for the lubricating grease to be unable to be quickly discharged, thereby improving the movement speed of the piston 6 and increasing the corresponding speed of opening or closing the valve.

[0045] Look again Figure 3 In this embodiment, the piston 6 and the first sealing component 8 are sealed and abutted to form a first annular sealing line, the diameter of which is D1. The piston 6 and the valve mouth 73b also form an annular seal, and the piston 6 has a lower end facing the valve mouth 73b, and the lower end of the piston 6 can abut the valve mouth 73b. Specifically, the lower end surface of the piston 6 can be provided with an annular protrusion 6c, and the annular protrusion 6c and the valve mouth 73b can be in line contact to increase the abutment pressure and ensure the sealing performance, so as to form a second annular sealing line, and the diameter of the second annular sealing line is D2. In this embodiment, the values ​​of D1 and D2 can be set to be equal so as not to affect the opening and closing of the valve, or the two can have a certain difference, but the difference is small. Specifically, the ratio of D1 to D2 can be controlled between 0.9 and 1.1.

[0046] Due to the setting of the balance hole 4a, the piston 6 has working medium with equal pressure on both sides of the axial direction. When D2<D1, there is an area difference between the working medium acting on the upper and lower sides of the piston 6. The pressure difference generated by the area difference is the downward valve closing back pressure. The larger the area difference, the greater the back pressure. This back pressure helps to close the valve, but also hinders the opening of the valve. Define the pressure difference as P1. Without considering gravity, P1 should satisfy: P1<the suction force of the moving iron core 4-the elastic force of the spring 5, and leave a certain redundancy to ensure that the solenoid valve can be opened normally. In addition, in the presence of back pressure, the solenoid valve has a certain reverse cut-off function, that is, it has a two-way cut-off function. Similarly, the area difference generated by D1<D2 will generate a reverse valve opening pressure. The larger the area difference, the greater the valve opening pressure. This valve opening pressure helps to open the valve, but also hinders the closing of the valve. This valve opening pressure is defined as P2, then P2 should satisfy P2<the spring force of the spring 5, and leave a certain redundancy to ensure reliable valve closing.

[0047] It can be seen that when the first sealing component 8 and the piston 6 are face-contact sealed, a first annular sealing surface can be formed, and the inner diameter of the first annular sealing surface is the above-mentioned D1. When the piston 6 and the valve mouth part 73b are face-contact sealed, a second annular sealing surface can be formed, and the inner diameter of the second annular sealing surface is the above-mentioned D2. Both can meet the above-mentioned ratio range of 0.9 to 1.1.

[0048] Please continue to refer to Fig.10 The top of the piston 6 in this embodiment is provided with a groove 6f, which penetrates the outer wall of the piston 6. Fig.11 , 12 It is understood that when the valve is opened, the first sealing component 8 and the piston 6 are out of contact, and the working medium in the space above the piston 6 can flow from the position of the groove 6f to the side of the piston 6 and be discharged, avoiding the working medium from affecting the valve opening.

[0049] You can continue to refer to Figure 3 , 6 In this embodiment, the first valve body 71 is fixed to the coil structure 3, and the inner side wall of the lower end of the first valve body 71 is provided with an annular first step portion 71a, and the first step portion 71a includes a first step surface 71a1 and a first step side wall 71a2. The second valve body 72 has an annular upper end surface 72c, and the upper end surface 72c, the first step surface 71a1, and the first step side wall 71a2 are surrounded to form an annular groove with the notch facing inward, and part of the first sealing component 8 is accommodated in the annular groove. In this way, the first sealing component 8 can be installed more conveniently. The outer side wall of the upper end of the second valve body 72 is also provided with a second step portion, and the second step portion includes a second step surface 72b. The lower end surface of the first valve body 71 can be pressed against the second step surface 72b, and the two can be fixed by welding, for example.

[0050] In this embodiment, Figure 3-5As shown, the second valve body 72 has a plurality of openings distributed along the circumferential direction, and the openings are the inlets 72a of the solenoid valve. For example, when the working medium is gas, the openings are the air inlets. This arrangement allows the working medium to enter the solenoid valve more evenly along the circumferential direction. The solenoid valve of this structure can be directly inserted into the corresponding working medium pipeline. Of course, it is also acceptable to have only one opening as the inlet 72a of the working medium.

[0051] The outer wall of the first valve body 71 may be provided with a first annular sealing groove, in which a second sealing component 10 is provided. The second sealing component may be a sealing ring. When the valve body of the solenoid valve is inserted into the corresponding pipeline, the second sealing component 10 may prevent leakage of the working medium.

[0052] The upper end face of the third valve body 73 is provided with a second annular sealing groove, and the second sealing groove is provided with a third sealing component 11. The third sealing component 11 can be a sealing gasket with a flat upper end face. The third valve body 73 is provided with the above-mentioned valve mouth part 73a, and the piston 6 can abut against the third sealing component 11 to achieve sealing of the valve mouth part 73a.

[0053] The third sealing component 11 can be made of a rubber material with high elasticity and low hardness, which is more conducive to the deformation sealing of the third sealing component during sealing.

[0054] The third valve body 73 can be made of PTFE-like materials with higher hardness, and the third sealing component 11 can be formed inside the second sealing groove by a rubber vulcanization process; the third sealing component 11 and the third valve body 73 are vulcanized into one body, ensuring the bonding reliability of the third valve body 73 and the third sealing component 11.

[0055] The second sealing groove has an upward opening. Along the axial direction of the third valve body 73, the projected area of ​​the opening of the second sealing groove can be smaller than the area of ​​the bottom wall of the second sealing groove. The third sealing component 11 can be formed inside the second sealing groove by a rubber vulcanization process.

[0056] The outer side wall of the third valve body 73 may be provided with an annular third sealing groove, and a fourth sealing component 9 may be provided in the third sealing groove. The fourth sealing component 9 may be a sealing ring. Of course, the sealing components in this embodiment may be sealing rings or sealing pads. The third valve body 73 has an axial through hole, the upper end of the axial through hole serves as the valve port 73b1 of the valve port portion 73b, and the lower end of the axial through hole serves as the outlet 73a of the solenoid valve. The third valve body 73 may be connected to a corresponding pipeline, and the fourth sealing component 9 may prevent leakage. In this embodiment, the valve body 7 is arranged in three sections for easy processing and assembly. It can be seen that the valve body 7 is an integrated structure, or it may be divided into two sections or other number of sections, and this embodiment does not make specific restrictions.

[0057] Specific examples are used herein to illustrate the principles and implementation methods of the present application, and the description of the above embodiments is only used to help understand the method and core ideas of the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A solenoid valve, characterized in that: It includes a valve body and a piston, the solenoid valve is provided with a valve port, and the piston can move along the axial direction of the solenoid valve to block or open the valve port; the solenoid valve also includes a first sealing component, and along the radial direction of the solenoid valve, the first sealing component is arranged between the valve body and the piston, and the outer wall of the piston includes a first wall portion and a second wall portion, and along the axial direction of the solenoid valve, the second wall portion is closer to the valve port than the first wall portion; in the closed valve state, the first wall portion and the first sealing component are abutted, and in the open valve state, the first wall portion and the first sealing component are not in contact, and there is a radial gap between the second wall portion and the first sealing component along the solenoid valve.

2. The solenoid valve according to claim 1, characterized in that: When the piston moves in the axial direction to open or close the valve, the second wall portion does not contact the first sealing component.

3. The solenoid valve according to claim 1 or 2, characterized in that: The first wall portion is an annular inclined surface, which is inclined relative to the axial direction. The inclined surface gradually inclines toward the middle of the piston in a direction close to the valve port. The first wall portion is in contact and sealed with the first sealing component.

4. The solenoid valve according to claim 3, characterized in that: The outer side wall of the piston has an annular groove, the first groove side wall of the annular groove away from the valve port is the first wall portion, and the bottom wall of the annular groove and its groove opposite to the second wall portion.

5. The solenoid valve according to claim 4, characterized in that: The annular groove includes a second groove side wall close to the valve port, the first groove side wall and the second groove side wall are arranged opposite to each other, and the second groove side wall does not contact the first sealing component when the valve is opened.

6. The solenoid valve according to any one of claims 1 to 5, characterized in that: The valve body includes a first valve body and a second valve body distributed along the axial direction, the second valve body is closer to the valve port, and one of the lower end of the first valve body and the upper end of the second valve body is provided with a step portion, and the step portion and the other cooperate to form an annular groove, and part of the first sealing component is accommodated in the annular groove.

7. The solenoid valve according to claim 6, characterized in that: At least one of the first valve body and the second valve body is provided with a guide portion for guiding the piston, the guide portion of the first valve body is located above the first sealing component, and the guide portion of the second valve body is located below the first sealing component.

8. The solenoid valve according to claim 1 or 6, characterized in that: The first sealing component comprises an annular sealing inner ring and an annular sealing outer ring, wherein the sealing outer ring is coated on the outer side of the sealing inner ring, the sealing inner ring is made of rubber material, and the sealing outer ring is made of polytetrafluoroethylene.

9. The solenoid valve according to any one of claims 1 to 8, characterized in that: The solenoid valve includes a coil structure, a moving iron core and a stationary iron core. The coil structure has an axial through hole. At least a portion of the stationary iron core is located in the axial through hole. The moving iron core can move axially along the axial through hole. The moving iron core is directly connected to the piston, and the moving iron core drives the piston to move axially.

10. The solenoid valve according to claim 9, characterized in that: A connecting piece is provided at one end of the moving iron core facing the valve port, and a connecting hole is provided at the piston. The connecting piece is inserted into the connecting hole and fixed by riveting.

11. The solenoid valve according to claim 9, characterized in that: The moving iron core is provided with a balancing hole, and the balancing hole includes a radial hole section and an axial hole section, the axial hole section penetrates the moving iron core axially, the radial hole section penetrates the moving iron core radially, and the radial hole section is connected to the axial hole section; the piston includes a cylindrical portion and a cover portion, the cover portion is arranged on one axial end of the cylindrical portion, the other end of the cylindrical portion is open and faces the valve mouth portion, and the axial hole section is connected to the inner cavity of the cylindrical portion.

12. The solenoid valve according to any one of claims 1 to 11, characterized in that: The first sealing component and the piston seal to form a first annular sealing surface or a first annular sealing line, the inner diameter of the first annular sealing surface or the diameter of the first annular sealing line is a first sealing diameter, the piston and the valve mouth seal to form a second annular sealing surface or a second annular sealing line, the inner diameter of the second annular sealing surface or the diameter of the second annular sealing line is a second sealing diameter, and the ratio of the first sealing diameter to the second sealing diameter is 0.9 to 1.

1.

13. The solenoid valve according to claim 12, characterized in that: At least part of the valve body is made of PTFE material, at least part of the valve mouth is made of rubber material, at least part of the valve mouth and part of the valve body are vulcanized into an integrated structure, and the rubber valve mouth can seal with the piston to form a second annular sealing surface or a second annular sealing line.

14. The solenoid valve according to claim 12 or 13, characterized in that: The lower end surface of the piston is provided with an annular protrusion, and the annular protrusion can abut against the valve mouth to form a second annular sealing line.

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