An electromagnetic valve

Abstract

This utility model relates to the field of hydraulic valve technology and discloses an electromagnetic valve, including a magnetic sleeve. The end of the magnetic sleeve has an axially oriented inner cavity forming a port. A moving iron is slidably disposed in the inner cavity. A push rod is provided at one end of the moving iron near the port. A stop is fixedly installed inside the magnetic sleeve, and the stop has a buffer cavity. One end of the push rod extends into the buffer cavity. A valve sleeve is fixedly connected to the port. A stop is fixed between the stop and the valve sleeve, and the stop has a central hole. A valve core assembly is disposed inside the valve sleeve. The valve core assembly has a transmission part, which passes through the central hole and connects to the push rod. A first annular permanent magnet is located in the buffer cavity, coaxially arranged with the central hole and fixedly connected to the stop. A second annular permanent magnet is located in the buffer cavity and embedded in the outer circumference of the push rod or the transmission part. This valve uses the magnetic force between the first and second annular permanent magnets to replace the elastic force of a helical compression mechanical spring, fundamentally avoiding the spring fatigue problem and improving the reliability and durability of the system.

Description

Technical Field

[0001] This utility model relates to the field of hydraulic valve technology, and more specifically to a solenoid valve. Background Technology

[0002] Common solenoid valves mainly consist of components such as a proportional electromagnet, a return spring, a valve sleeve, and a valve core. Their working principle is primarily based on Faraday's law of electromagnetic induction. The solenoid valve uses the electromagnetic force generated by the solenoid coil to push the valve core, thereby changing the opening of the fluid passage and controlling the flow rate, pressure, and direction of the fluid. When the solenoid coil is energized, the electromagnetic force overcomes the spring force, moving the valve core to a new position and adjusting the direction of the fluid passage. When the solenoid coil is de-energized, the spring force of the return spring pushes the valve core back to its initial position. The return spring is mostly a helical compression mechanical spring. Due to the long-term action of pressurized fluid, the spring may experience fatigue fracture, relaxation, plastic deformation, permanent deformation, and other failure modes due to long-term cyclic operation, affecting the reliability and lifespan of the valve. Furthermore, the spring may occupy additional space, which may be detrimental to miniaturization or specific layout designs. Utility Model Content

[0003] To address the problem of reduced valve reliability and lifespan caused by fatigue fracture, relaxation, and plastic deformation (including permanent deformation) of helical compression springs under long-term cyclic conditions, this utility model provides a solenoid valve.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0005] An electromagnetic valve includes: a magnetic sleeve, wherein an inner cavity is axially formed at one end of the magnetic sleeve and a port is formed at the end of the magnetic sleeve; a moving iron, axially slidably disposed in the inner cavity, wherein a push rod is provided at one end of the moving iron near the port, a stop iron is fixedly installed inside the magnetic sleeve, the stop iron has a buffer cavity, and one end of the push rod extends into the buffer cavity; and a valve sleeve, wherein the valve sleeve is fixedly connected to the port of the magnetic sleeve, the valve sleeve has a valve core receiving cavity, and a valve core assembly is axially slidably disposed within the valve core receiving cavity. A valve port is formed between the component and the valve sleeve; a stop block is fixedly installed between the stop block and the valve sleeve, the stop block has a central hole, the valve core assembly has a transmission part, the transmission part passes through the central hole and is connected to the push rod; a first annular permanent magnet is located in the buffer cavity, the first annular permanent magnet is fixedly connected to the stop block, and the first annular permanent magnet is coaxial with the central hole; a second annular permanent magnet is located in the buffer cavity, the second annular permanent magnet is embedded in the outer peripheral surface of the push rod or the transmission part.

[0006] As an alternative, the push rod or the transmission part has a groove along the circumference, and a portion of the second annular permanent magnet is embedded in the groove to achieve axial positioning. The first annular permanent magnet is fixedly connected to the stop by an adhesive.

[0007] As an optional solution, the stop block is provided with a first annular groove, and the first annular permanent magnet is interference-fitted with the first annular groove.

[0008] As an optional solution, it also includes a magnet base, wherein the push rod or the transmission part is provided with a magnet base groove along the circumference, a part of the magnet base is embedded in the magnet base groove, and a second annular groove is provided on the end face of the magnet base near the end of the first annular permanent magnet, and the second annular permanent magnet is interference-fitted with the second annular groove.

[0009] As an alternative, the magnet base is made of a magnetically shielding material.

[0010] As an alternative, the second annular permanent magnet includes two semi-annular permanent magnets, the splicing ends of which are provided with serrated mating surfaces, and the serrated mating surfaces are fixedly connected by adhesive.

[0011] As an optional solution, a fastening sleeve is fitted on the outer surface of the second annular permanent magnet, and the tooth structure of the sawtooth mating surface is triangular, trapezoidal, or wavy.

[0012] As an alternative, the first and second annular permanent magnets are arranged opposite each other with the same poles. When the control signal is zero (no power), the repulsive force between the first and second annular permanent magnets causes the valve to open.

[0013] As an alternative, the moving iron is provided with a first T-shaped groove, and the push rod is provided with a first T-shaped head at one end near the moving iron, the first T-shaped head being embedded in the first T-shaped groove.

[0014] As an alternative, the push rod has a second T-shaped groove at one end near the valve core assembly, and the transmission part has a second T-shaped head, which is embedded in the second T-shaped groove.

[0015] The beneficial effects of this utility model are:

[0016] This invention eliminates the helical compression mechanical spring in the solenoid valve, instead employing two spaced permanent magnets. The repulsive magnetic force generated by these two magnets replaces the elastic force of the helical compression mechanical spring, thus not only fundamentally avoiding the spring fatigue problem and significantly improving the reliability and durability of the system, but also achieving faster response and more precise control. Furthermore, by reducing reliance on the helical compression mechanical spring, the solenoid valve structure is simplified, effectively reducing manufacturing costs and meeting lightweight design requirements. Attached Figure Description

[0017] Figure 1 A cross-sectional view of the solenoid valve provided by this utility model;

[0018] Figure 2 A partially enlarged schematic diagram of a second embodiment of the connection between the first annular permanent magnet and the stop iron provided by this utility model;

[0019] Figure 3 A partially enlarged schematic diagram of a first embodiment of the connection between the second annular permanent magnet and the push rod or transmission part provided by this utility model;

[0020] Figure 4 Schematic diagrams of different forms of the sawtooth-shaped bonding surface of the semi-annular permanent magnet provided by this utility model;

[0021] Figure 5 This is a partially enlarged schematic diagram of a second embodiment of the present invention, in which the second annular permanent magnet is connected to a push rod or transmission part.

[0022] In the picture:

[0023] 1. Magnetic sleeve; 2. Port; 3. Moving iron; 4. Push rod; 5. Stop; 51. Buffer cavity;

[0024] 6. Valve sleeve; 61. Valve core receiving cavity; 7. Valve core assembly; 71. Main valve core; 72. Pilot valve core;

[0025] 721. Transmission unit; 8. Valve port; 9. Stop block; 91. Center hole; 10. First annular permanent magnet;

[0026] 11. Second annular permanent magnet; 12. Groove; 13. Semi-annular permanent magnet; 14. Serrated mating surface;

[0027] 15. Fastening sleeve; 16. First annular groove; 17. Magnet seat; 18. Magnet seat groove;

[0028] 19. Second annular groove; 20. First T-shaped groove; 21. First T-shaped head;

[0029] 22. Second T-shaped groove; 23. Second T-shaped head; 24. Limiting step. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the invention and not the entire structure.

[0031] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of description and simplification of operation, and are not intended to 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 the present invention.

[0032] Reference Figure 1 , Figure 2 This utility model provides an electromagnetic valve, including a magnetic sleeve 1, a valve sleeve 6, a moving iron 3, a push rod 4, a stop 5, a stop block 9, a first annular permanent magnet 10, a second annular permanent magnet 11, and a valve core assembly 7. The magnetic sleeve 1 has an axially oriented inner cavity at one end, with a port 2 formed thereon. The valve sleeve 6 is threadedly connected to the magnetic sleeve 1 through the port 2. The moving iron 3 is axially guided and slidably disposed within the inner cavity. A push rod 4 is provided at one end of the moving iron 3 near the port 2, and the push rod 4 is coaxially and fixedly connected to the moving iron 3. In one embodiment, a first T-shaped groove 20 is provided on the moving iron 3, and a first T-shaped head 21 is provided at one end of the push rod 4 near the moving iron 3, the first T-shaped head 21 being engaged within the first T-shaped groove 20.

[0033] A stop 5 is provided at one end of the moving iron 3 near port 2. The stop 5 has a stepped outer circumferential surface. The magnetic sleeve 1 has a stepped limiting step 24. The stepped outer circumferential surface of the stop 5 abuts against the limiting step 24. A stop block 9 is provided at one end of the stop 5 near port 2. One end of the stop block 9 abuts against the stop 5, and the other end abuts against the valve sleeve 6. The stop 5 and the stop block 9 achieve axial limiting and fixing by means of the thread preload of the magnetic sleeve 1 and the valve sleeve 6.

[0034] The stop 5 has a through hole along its axis. The through hole expands at the end near port 2 to form a buffer cavity 51. The push rod 4 extends into the buffer cavity 51 through the through hole. The valve sleeve 6 has a valve core receiving cavity 61 extending through its axis. The valve core assembly 7 is slidably disposed in the valve core receiving cavity 61 along its axis. A valve port 8 for controlling the flow of fluid is formed between the valve core assembly 7 and the valve sleeve 6. The valve core assembly 7 includes a main valve core 71 and a pilot valve core 72. The main valve core 71 has a unidirectional through chamber. The pilot valve core 72 is slidably disposed in the chamber of the main valve core 71 along its axis. A transmission part 721 extends from the end of the pilot valve core 72 away from the valve port 8.

[0035] The stop block 9 has a central hole 91, and the transmission part 721 extends into the buffer cavity 51 through the central hole 91 and is fixedly connected to the push rod 4. In one embodiment, the end of the push rod 4 away from the moving iron 3 is provided with a second T-shaped groove 22, and the end of the transmission part 721 near the push rod 4 is provided with a second T-shaped head 23, which is engaged in the second T-shaped groove 22.

[0036] The first annular permanent magnet 10 and the second annular permanent magnet 11 are both located within the buffer cavity 51 and are arranged opposite each other with the same pole. The first annular permanent magnet 10 is fixedly connected to the end face of the stop 5 near the buffer cavity 51, and the first annular permanent magnet 10 is coaxially arranged with the center hole 91 of the stop 5. The second annular permanent magnet 11 is embedded in the outer peripheral surface of the push rod 4 or the transmission part 721, and can move left and right with the push rod 4 or the transmission part 721 to change the distance between it and the first annular permanent magnet 10, thereby changing the magnitude of the magnetic force between them. Furthermore, the second annular permanent magnet 11, under the influence of repulsive force, can drive the push rod 4 or the pilot valve core 72 to move away from the first annular permanent magnet 10. When the control signal is zero (no power), the repulsive force between the first annular permanent magnet 10 and the second annular permanent magnet 11 causes the valve port 8 to open.

[0037] The fixed connection between the first annular permanent magnet 10 and the stop 5 can be implemented in several ways. In a first embodiment, the first annular permanent magnet 10 is fixedly connected to the end face of the stop 5 near the buffer cavity 51 by adhesive. This method does not require additional processing of other structures for fixing the first annular permanent magnet 10, thus saving processing costs.

[0038] Reference Figure 2 In the second embodiment, a first annular groove 16 is formed on the end face of the stop block 9 near the buffer cavity 51. At least a portion of the first annular permanent magnet 10 is embedded in the first annular groove 16 and is fixed in position with the first annular groove 16 through an interference fit. This mechanical fixing method has higher reliability than adhesive fixing and is easy to disassemble. During valve testing, if the valve force does not meet the requirements, the valve closing force can be adjusted by replacing the first annular permanent magnet 10, effectively improving the error tolerance of the processing and reducing quality costs. When the pressure conditions of the application scenario change, the first annular permanent magnet 10 can also be replaced to change the valve closing force, thereby adapting to the usage requirements of different scenarios.

[0039] There are also various embodiments for connecting the second annular permanent magnet 11 to the push rod 4 or the transmission part 721. (Refer to...) Figure 3 , Figure 4In the first embodiment, a groove 12 is provided circumferentially on the outer peripheral surface of the push rod 4 or the transmission part 721, and a portion of the second annular permanent magnet 11 is embedded in the groove 12 to achieve axial positioning. Specifically, the second annular permanent magnet 11 includes two semi-annular permanent magnets 13, and the splicing ends of the two semi-annular permanent magnets 13 are provided with mutually adaptable sawtooth-shaped mating surfaces 14. During assembly, the two semi-annular permanent magnets 13 are fixedly connected by adhesive. The sawtooth-shaped mating surfaces 14 can increase the contact area (i.e., the area of ​​adhesive coating) of the two semi-annular permanent magnets 13, thereby improving the bonding strength. The tooth structure of the sawtooth-shaped mating surfaces can adopt various forms such as triangle, trapezoid, and wave. Furthermore, a fastening sleeve 15 is fitted on the outer surface of the second annular permanent magnet 11. The fastening sleeve 15 can be made of a material with a certain degree of elasticity, such as nylon or polytetrafluoroethylene, to provide radial constraint force and make the structure of the second annular permanent magnet 11 more stable.

[0040] Reference Figure 5 In the second embodiment, the solenoid valve further includes a magnet seat 17 made of magnetically shielding material. A magnetic seat groove 18 is circumferentially formed on the outer peripheral surface of the push rod 4 or transmission part 721. A portion of the magnet seat 17 is embedded in the magnetic seat groove 18 (the way the magnet seat 17 is embedded in the magnetic seat groove 18 can refer to the first embodiment described above where the second annular permanent magnet 11 is connected to the push rod 4 or transmission part 721). A second annular groove 19 is formed on the end face of the magnet seat 17 near the end of the first annular permanent magnet 10. The second annular permanent magnet 11 is sleeved on the push rod 4 or transmission part 721, and at least a portion of it is embedded in the second annular groove 19 by an interference fit. In this embodiment, the second annular permanent magnet 11 is a single annular permanent magnet. Compared to the first embodiment, this avoids splicing gaps, results in a more continuous magnetic field distribution, and improves the consistency of force and the control accuracy of the valve. The magnet seat 17 uses magnetically shielding material, which can effectively shield the magnetic field from leakage, reduce the mutual influence between the moving iron 3 and the second annular permanent magnet 11, and improve the control accuracy of the valve. In addition, the magnet base 17 can also provide mechanical protection for the second annular permanent magnet 11, reduce the risk of the second annular permanent magnet 11 being impacted by external forces, and extend its service life.

[0041] The working principle of this utility model is as follows: When the control signal is zero (no power), the moving iron 3 and the stop iron 5 are not magnetized, and no electromagnetic force is generated between them. At this time, under the action of the repulsive force between the first annular permanent magnet 10 and the second annular permanent magnet 11 and the hydraulic pressure, the pilot valve core 72 and the main valve core 71 are located on the far left, and the valve port 8 is opened to the maximum extent, with the largest flow area, realizing the maximum output flow of the valve. As the control signal gradually increases, the electromagnetic force between the moving iron 3 and the stop iron 5 overcomes the repulsive force between the first annular permanent magnet 10 and the second annular permanent magnet 11, driving the push rod 4 and the pilot valve core 72 to move to the right. At the same time, under the action of hydraulic pressure, the main valve core 71 follows the pilot valve core 72 to move to the right, the valve port 8 gradually decreases, and the flow area gradually decreases.

[0042] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A solenoid valve, characterized in that, include: A magnetic sleeve (1) is provided with an inner cavity along the axial direction at the end of the magnetic sleeve (1) and a port (2) is formed at the end of the magnetic sleeve; A moving iron (3) is axially slidably disposed in the inner cavity. A push rod (4) is provided at one end of the moving iron (3) near the port (2). A stop iron (5) is fixedly installed inside the magnetic sleeve (1). The stop iron (5) is provided with a buffer cavity (51). One end of the push rod (4) extends into the buffer cavity (51). A valve sleeve (6) is fixedly connected to the port (2) of the magnetic sleeve (1). The valve sleeve (6) has a valve core receiving cavity (61). A valve core assembly (7) is axially slidably disposed in the valve core receiving cavity (61). A valve port (8) is formed between the valve core assembly (7) and the valve sleeve (6). A stop block (9) is fixedly installed between the stop iron (5) and the valve sleeve (6). The stop block (9) has a central hole (91). The valve core assembly (7) has a transmission part (721). The transmission part (721) passes through the central hole (91) and is connected to the push rod (4). The first annular permanent magnet (10) is located in the buffer cavity (51). The first annular permanent magnet (10) is fixedly connected to the stop block (9). The first annular permanent magnet (10) is coaxial with the central hole (91). The second annular permanent magnet (11) is located in the buffer cavity (51) and is embedded in the outer peripheral surface of the push rod (4) or the transmission part (721).

2. The solenoid valve according to claim 1, characterized in that: The push rod (4) or the transmission part (721) has a groove (12) in the circumferential direction. A part of the second annular permanent magnet (11) is embedded in the groove (12) to achieve axial positioning. The first annular permanent magnet (10) is fixedly connected to the stop (5) by adhesive.

3. The solenoid valve according to claim 1, characterized in that: The stop block (9) is provided with a first annular groove (16), and the first annular permanent magnet (10) is interference-fitted with the first annular groove (16).

4. A solenoid valve according to claim 1, characterized in that: It also includes a magnet seat (17), and the push rod (4) or the transmission part (721) is provided with a magnet seat groove (18) in the circumferential direction. A part of the magnet seat (17) is embedded in the magnet seat groove (18). The end face of the magnet seat (17) near the first annular permanent magnet (10) is provided with a second annular groove (19). The second annular permanent magnet (11) and the second annular groove (19) are interference fit.

5. A solenoid valve according to claim 4, characterized in that: The magnet base (17) is made of magnetic shielding material.

6. A solenoid valve according to claim 2, characterized in that: The second annular permanent magnet (11) includes two semi-annular permanent magnets (13), and the splicing ends of the semi-annular permanent magnets (13) are provided with serrated mating surfaces (14), and the serrated mating surfaces (14) are fixedly connected by adhesive.

7. A solenoid valve according to claim 6, characterized in that: The outer surface of the second annular permanent magnet (11) is fitted with a fastening sleeve (15), and the tooth structure of the sawtooth mating surface (14) is triangular, trapezoidal, or wavy.

8. A solenoid valve according to any one of claims 2, 3, 4, and 6, characterized in that: The first annular permanent magnet (10) and the second annular permanent magnet (11) are arranged opposite each other with the same pole. When the control signal is zero, the repulsive force between the first annular permanent magnet (10) and the second annular permanent magnet (11) causes the valve port (8) to open.

9. A solenoid valve according to claim 8, characterized in that: The moving iron (3) has a first T-shaped groove (20), and the push rod (4) has a first T-shaped head (21) at one end near the moving iron (3), and the first T-shaped head (21) is embedded in the first T-shaped groove (20).

10. A solenoid valve according to claim 9, characterized in that: The push rod (4) has a second T-shaped groove (22) at one end near the valve core assembly (7), and the transmission part (721) has a second T-shaped head (23), which is embedded in the second T-shaped groove (22).

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