A shock absorber damping adjustable solenoid valve

Abstract

The present invention provides a shock absorber damping adjustable solenoid valve, which includes a valve sleeve, a main spool, a main valve cavity and a main return spring. A first check valve and a second check valve are arranged on the main spool. An oil outlet passage is formed on the valve sleeve. A housing is sleeved on the upper end of the valve sleeve. An oil outlet gap is left between the bottom of the housing and the top of the valve sleeve. A third check valve and a fourth check valve are arranged on the valve sleeve. A pilot valve for communicating with the oil outlet passage is arranged in the main valve cavity. An electromagnetic drive assembly for driving the pilot valve to operate is arranged on the housing. During compression, the oil first passes through the first check valve and then enters the pilot valve, and then the main spool is opened. During restoration, the oil first passes through the second check valve and then enters the pilot valve, and then the main spool is opened. The present invention provides a shock absorber damping adjustable solenoid valve. The pilot valve participates in the damping adjustment process during both the compression and restoration strokes, effectively reducing the requirement of the damping adjustment valve for electromagnetic force, and obtaining a wider pressure-flow adjustment range with a smaller electromagnetic force.

Description

Technical Field

[0001] The present invention relates to the technical field of automotive tire wear collection, and more specifically, to a shock absorber damping adjustable solenoid valve. Background Art

[0002] A shock absorber is used to suppress the oscillation after the shock absorption spring rebounds and the impact from the road surface. It is widely used in automotive shock absorption to attenuate the vibration of the vehicle frame and body, thereby improving the driving smoothness of the vehicle. When the vehicle passes over an uneven road surface, although the shock absorption spring can filter the road surface vibration, the shock absorption spring itself will still have reciprocating motion, and the shock absorber is used to suppress this jumping of the shock absorption spring. The shock absorber is filled with oil and has two chambers, an inner chamber and an outer chamber. The oil can flow through the pores connecting the two chambers. When the wheel bumps, the piston in the shock absorber will move up and down in the sleeve, and the oil in its chamber will flow back and forth between the two chambers under the action of the reciprocating motion of the piston. The damping control solenoid valve controls the size of the oil passage switch to change the resistance of the oil flowing back and forth between the chambers, thereby realizing the change of the shock absorber damping.

[0003] Patent CN103511541A discloses a pilot overflow valve structure. The use of this built-in damping regulating valve is divided into two strokes: compression and restoration. In the compression stroke, by adjusting the magnitude of the input current, the opening degree of the main spool is controlled, thereby adjusting the pressure of the overflow valve. In the restoration stroke, by adjusting the magnitude of the input current, the pressure of the pilot chamber is controlled, thereby controlling the opening degree of the main spool of the overflow valve and adjusting the pressure of the overflow valve; thus realizing the adjustment of different damping. It can be seen from the attached drawings that the structure of this damping regulating valve is very complex, and the corresponding cost is relatively high; and in the compression stroke, the pilot valve does not participate in the pressure regulation, that is, a greater electromagnetic force is required. The zero-current failure mode relies on the moving iron core to achieve, or increases the complex structure, resulting in an increase in cost. Summary of the Invention

[0004] The problem solved by the present invention is to provide a shock absorber damping adjustable solenoid valve to overcome at least one defect in the prior art.

[0005] To solve the above problems, the present invention provides a shock absorber damping adjustable solenoid valve, including a valve sleeve. An installation cavity with an opening facing downwards is provided at the lower end of the valve sleeve, and the opening end of the installation cavity communicates with the oil inlet passage. A main spool is slidably fitted in the installation cavity, so that a main valve cavity is formed between the main spool and the bottom of the installation cavity, and a main return spring is provided between the main spool and the bottom of the installation cavity. A first one-way valve for communicating the main valve cavity with the oil inlet passage and a second one-way valve for communicating the main valve cavity with the oil outlet passage are provided on the main spool.

[0006] An oil outlet passage communicating with the installation cavity is formed in the side wall of the valve sleeve. A housing is sleeved on the upper end of the valve sleeve, and an oil outlet gap is left between the bottom of the housing and the top of the valve sleeve. A first oil passage for communicating the oil inlet passage with the oil outlet gap and a second oil passage for communicating the oil outlet passage with the oil outlet gap are respectively arranged on the valve sleeve. A third one-way valve and a fourth one-way valve are respectively arranged in the first oil passage and the second oil passage.

[0007] A pilot valve for communicating the main valve cavity with the oil outlet gap is further arranged at the bottom of the installation cavity. The pilot valve comprises an upper valve seat, a lower valve seat and a valve ball. A pilot cavity is formed between the upper valve seat and the lower valve seat. Pilot valve holes for communicating the main valve cavity with the pilot cavity and for communicating the pilot cavity with the oil outlet gap are respectively arranged in the middle parts of the upper valve seat and the lower valve seat. An oil outlet small hole is further arranged on the upper valve seat. A pilot return spring is arranged on the lower valve seat, so that the valve ball always has a tendency to move upward to seal the upper valve seat. A push rod and an electromagnetic driving assembly for driving the push rod to move up and down are arranged at the upper end of the housing. When the electromagnetic driving assembly is powered on, the push rod can move downward to enable the valve ball to move downward after overcoming the elastic force of the pilot return spring and the hydraulic pressure. During compression, a small part of the oil in the oil inlet passage enters the pilot valve through the first one-way valve and then flows into the oil outlet passage through the fourth one-way valve. Under the action of the pilot valve, the main valve core is opened, and most of the oil enters the oil outlet passage from the gap between the main valve core and the installation cavity. During restoration, a small part of the oil in the oil outlet passage enters the pilot valve through the second one-way valve and then flows back to the liquid inlet passage through the third one-way valve. Under the action of the pilot valve, the main valve core is opened, and most of the oil flows back to the oil outlet passage from the gap between the main valve core and the installation cavity.

[0008] The electromagnetic valve of the present invention has the following advantages compared with the prior art:

[0009] 1. When the electromagnetic valve is not powered on, the valve ball will be pushed by the pilot return spring and the hydraulic pressure to the sealing chamfer of the upper valve seat. The oil in the pilot cavity will only flow to the oil outlet passage through the oil outlet small hole. This mode is defined as the 0 mA failure mode, that is, a relatively large damping force will still be maintained in the case of vehicle failure, improving the safety of the vehicle. And the area of the oil outlet small hole can be adjusted to meet the requirements of different vehicles.

[0010] 2. The pressure in the pilot cavity is adjusted by the position of the valve ball. The pilot valve participates in the damping adjustment process during both the compression and restoration strokes, greatly reducing the requirement of the damping regulating valve for the electromagnetic force, that is, a smaller electromagnetic force can be used to obtain a wider pressure-flow adjustment range.

[0011] 3. During the compression process, the first one-way valve is designed inside the main valve. The compression chamber serves as the main oil chamber, and the pressure oil enters the intermediate chamber through the one-way valve. The hydraulic oil volume passing through this one-way valve is small, which can reduce the size of the one-way valve. At the same time, since most of the pressure oil flows out through the opening between the main spool and the valve sleeve, the CDC valve has a larger flow range and a more compact overall structure. Additionally, the fourth one-way valve only controls the outflow of the hydraulic oil of the pilot valve, and the main valve oil circuit is not affected by this fourth one-way valve. This makes the volume of the liquid flowing into the fourth one-way valve small, facilitating control, with a fast response speed, and also reducing the size of the one-way valve, thereby reducing the overall size of the CDC valve.

[0012] 4. During the restoration process, the second one-way valve is designed inside the main valve. The restoration chamber serves as the main oil chamber, and the pressure oil enters the intermediate chamber through the second one-way valve. The hydraulic oil volume passing through the second one-way valve is small, which can reduce the size of the one-way valve. At the same time, since most of the pressure oil flows out through the opening between the main spool and the valve sleeve and is not restricted by the one-way valve, the CDC valve has a larger flow range and a more compact overall structure. Additionally, the third one-way valve only controls the outflow of the hydraulic oil of the pilot valve, and the main valve oil circuit is not affected by the third one-way valve. This makes the volume of the liquid flowing into the third one-way valve small during restoration, facilitating control, with a fast response speed, and also reducing the size of the one-way valve, thereby reducing the overall size of the CDC valve.

[0013] As an improvement, an inwardly concave upper sealing cavity is provided on the lower end surface of the upper valve seat, and an inwardly concave lower sealing cavity is provided on the upper end surface of the lower valve seat. The pilot valve holes are opened at the bottoms of both the upper sealing cavity and the lower sealing cavity; a spring hole for accommodating the pilot return spring is also provided at the bottom of the lower sealing cavity.

[0014] In a further improvement, the electromagnetic drive assembly includes a coil, a magnetic conducting tube, and an armature. The magnetic conducting tube is a sleeve with an open lower part, and the outer circle of the sleeve is fitted on the inner wall of the coil. The outer wall of the coil is connected to the housing; the armature is slidably fitted in the sleeve in the vertical direction, and the upper end of the push rod is fixedly connected to the armature; a sealing cover plate is also provided at the top of the housing.

[0015] In a further improvement, the upper side wall of the housing surrounds the outside of the coil, and the housing is made of a soft magnetic material so that a magnetic closed loop can be formed between the housing and the coil.

[0016] In a further improvement, an annular elastic piece is provided at a position in the installation cavity close to the lower valve seat, and the elastic force of the elastic piece is less than that of the main return spring; the outer end of the elastic piece in the radial direction is fitted with the installation cavity, and there is a movable space between the inner end of the elastic piece in the radial direction and the lower valve seat; the upper end of the main return spring abuts against the lower surface of the inner end of the elastic piece.

[0017] Further improvement: a connecting column is formed at the lower end of the lower valve seat, and the pilot valve hole and the spring hole of the lower valve seat are both axially arranged on the connecting column; the connecting column is movably inserted into the inner hole of the elastic sheet, and the upper end of the main return spring is slidably sleeved outside the connecting column.

[0018] Further improved, a limiting ring is assembled at the opening end of the installation cavity, and the upper end surface of the limiting ring abuts against the lower end surface of the main valve core.

[0019] In addition, other improved features and advantages of the present invention will be described in the subsequent specific embodiments, and part of them will become obvious from the specification or be understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures specifically pointed out in the specification and the drawings. Brief Description of the Drawings

[0020] Figure 1 is a three-dimensional structure diagram of the shock absorber damping adjustable solenoid valve of the present invention;

[0021] Figure 2 is Figure 1 a half-sectional view of the shock absorber damping adjustable solenoid valve in

[0022] Figure 3 is Figure 2 a partial schematic diagram of the cross-sectional view of the shock absorber damping adjustable solenoid valve in

[0023] Figure 4 is Figure 3 an enlarged structure diagram at X in

[0024] Figure 5 is a hydraulic flow direction diagram of the shock absorber damping adjustable solenoid valve of the present invention during the compression process;

[0025] Figure 6 is a hydraulic flow direction diagram of the shock absorber damping adjustable solenoid valve of the present invention during the restoration process.

[0026] Description of the Reference Numerals:

[0027] 1. Valve sleeve; 2. Installation cavity; 3. Main valve core; 4. Main valve cavity; 5. Main return spring; 6. First check valve; 7. Second check valve; 8. Oil outlet channel; 9. Housing; 10. Oil outlet gap; 11. First oil passage, 12. Second oil passage; 13. Third check valve; 14. Fourth check valve; 15. Upper valve seat; 16. Lower valve seat; 17. Valve ball; 18. Pilot valve hole; 19. Oil outlet small hole; 20. Pilot return spring; 21. Push rod; 22. Upper sealing cavity; 23. Lower sealing cavity; 24. Spring hole; 25. Coil; 26. Magnetic conduction tube; 27. Armature; 28. Sealing cover plate; 29. Elastic sheet; 30. Connecting column; 31. Limiting ring. Detailed Embodiments

[0028] To more clearly and completely describe the objectives, technical solutions, and advantages of the embodiments of the present invention, the following further elaborates on the shock absorber damping adjustable solenoid valve of the present invention with reference to the accompanying drawings. Herein, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art currently without making creative achievements fall within the scope of protection of the present invention.

[0029] Here, it should be noted that in order to avoid obscuring the present invention due to unnecessary details, only the structures and / or processing steps closely related to the solution of the present invention are shown in the drawings, while other details less related to the present invention are omitted.

[0030] It should be emphasized that the terms "comprising / including / having" when used herein refer to the presence of features, elements, steps, or components, but do not exclude the presence or addition of one or more other features, elements, steps, or components. In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper end", "lower end", "inner end", "outer end", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description. The actual directions and relative positions of each component can change according to the position of the observer.

[0031] As Figure 1 、 2 shown, the present invention provides a shock absorber damping adjustable solenoid valve, including a valve sleeve 1. The lower end of the valve sleeve 1 is provided with an installation cavity 2 with an opening facing downwards, and the opening end of the installation cavity 2 communicates with the oil inlet passage. A main spool 3 is slidably fitted in the installation cavity 2, and the main spool 3 and the valve sleeve 1 are in clearance fit, so that a main valve cavity 4 is formed between the main spool 3 and the bottom of the installation cavity 2. A main return spring 5 is provided between the main spool 3 and the bottom of the installation cavity 2. A first check valve 6 for communicating the main valve cavity 4 with the oil inlet passage and a second check valve 7 for communicating the main valve cavity 4 with the oil outlet passage 8 are provided on the main spool 3;

[0032] An oil outlet passage 8 communicating with the installation cavity 2 is opened on the side wall of the valve sleeve 1. A housing 9 is sleeved on the upper end of the valve sleeve 1. An oil outlet gap 10 is left between the bottom of the housing 9 and the top of the valve sleeve 1. A first oil passage 11 for communicating the oil inlet passage with the oil outlet gap 10 and a second oil passage for communicating the oil outlet passage 8 with the oil outlet gap 10 are respectively provided on the valve sleeve 1. A third check valve 13 and a fourth check valve 14 are respectively provided in the first oil passage 11 and the second oil passage;

[0033] A pilot valve for connecting the main valve chamber 4 and the oil outlet clearance 10 is also arranged at the bottom of the installation chamber 2. During compression, a small part of the oil in the oil inlet passage enters the pilot valve from the first one-way valve 6 and then flows into the oil outlet passage 8 through the fourth one-way valve 14. Under the action of the pilot valve, the main valve core 3 is opened, and most of the oil enters the oil outlet passage 8 from the clearance between the main valve core 3 and the installation chamber 2. During restoration, a small part of the oil in the oil outlet passage 8 enters the pilot valve from the second one-way valve 7 and then flows back to the liquid inlet passage through the third one-way valve 13. Under the action of the pilot valve, the main valve core 3 is opened, and most of the oil flows back to the oil outlet passage 8 from the clearance between the main valve core 3 and the installation chamber 2.

[0034] More specifically, as Figure 3 , 4 shown, the pilot valve includes an upper valve seat 15, a lower valve seat 16 and a valve ball 17. A pilot chamber is formed between the upper valve seat 15 and the lower valve seat 16. The valve ball 17 is movably fitted in the pilot chamber, and conical surfaces capable of hermetically cooperating with the valve ball 17 are arranged on both the upper valve seat 15 and the lower valve seat 16. Pilot valve holes 18 for connecting the main valve chamber 4 and the pilot chamber and for connecting the pilot chamber and the oil outlet clearance 10 are respectively arranged in the middle parts of the upper valve seat 15 and the lower valve seat 16. An oil outlet small hole 19 is also arranged on the upper valve seat 15, and a pilot return spring 20 is arranged on the lower valve seat 16 so that the valve ball 17 always has a tendency to move upward to seal the upper valve seat 15. A push rod 21 and an electromagnetic drive assembly for driving the push rod 21 to move up and down are arranged at the upper end of the housing 9. When the electromagnetic drive assembly is powered on, the push rod 21 can move downward so that the valve ball 17 moves downward after overcoming the elastic force of the pilot return spring 20 and the hydraulic action force.

[0035] Preferably, in this embodiment, the electromagnetic drive assembly includes a coil 25, a magnetic conduction tube 26 and an armature 27. The magnetic conduction tube 26 is a sleeve with an open lower part. The outer ring of the sleeve is fitted on the inner wall of the coil 25, and the outer wall of the coil 25 is connected to the housing 9. The armature 27 is slidably fitted in the sleeve in the vertical direction, and the upper end of the push rod 21 is fixedly connected to the armature 27. The top of the push rod 21 is in interference fit with the armature 27 to form an armature 27 assembly, and a sealing cover plate 28 is also arranged at the top of the housing 9.

[0036] More specifically, in this structure, the upper side wall of the housing 9 surrounds the outside of the coil 25, and the housing 9 is made of a soft magnetic material so that a magnetic closed loop can be formed between the housing 9 and the coil 25. Compared with the existing traditional solenoid valve structure, there is no housing 9 outside the coil 25, and a magnetic circuit needs to be formed between it and the piston rod outside the whole solenoid valve. Therefore, there are special requirements for the material of the piston rod in the traditional structure. However, in the application, since the housing 9 made of a soft magnetic material is arranged, a magnetic circuit can be formed between it and the coil 25. Therefore, there are no other requirements for the material of the piston rod outside the whole solenoid valve, that is, the damping regulating valve of the application is not limited by the piston rod, and the material of the piston rod has no influence on the performance of the damping valve.

[0037] In the above structure, when the coil 25 is de-energized, the spring force generated by the pilot return spring 20 pushes the valve ball 17 upward to the stop position. At this time, there will be a certain gap between the lower part of the ejector rod 21 and the valve ball 17. At this time, the valve ball 17 will be seated on the chamfer of the upper valve seat 15 to produce a sealing function. At this time, the oil will only flow to the oil outlet channel 8 through the oil outlet small hole 19 on the upper valve seat 15, generating a relatively large damping. That is, the function realized at this time is zero-current protection with moderate damping.

[0038] When the coil 25 is energized, the magnetic force generated by the magnetic field of the coil 25 will cause the armature 27 and the ejector rod 21 to move downward, and overcome the spring force of the pilot return spring 20 to press the valve ball 17 on the chamfer of the lower valve seat 16. By adjusting the magnitude of the current, different electromagnetic forces are generated to adjust the pressure in the pilot valve cavity. After the downward acting force of the ejector rod 21 overcomes the spring force of the pilot return spring 20, the pilot valve hole 18 on the lower valve seat 16 opens, and the oil in the pilot cavity will flow to the oil outlet in two ways. One way is through the oil outlet small hole 19, and the other way is through the throttling gap between the valve ball 17 and the upper valve seat 15, and finally converges to the fourth one-way valve 14 on the upper part of the valve sleeve 1 and flows out to the oil outlet channel 8.

[0039] Since the magnitude of the magnetic force is linearly related to the magnitude of the current, different currents mean different positions of the ball valve, that is, different interception areas. It means that the pressure in the pilot cavity can be adjusted according to the magnitude of the given current. For the main spool 3, it will be subjected to an upward hydraulic pressure. At the same time, since the main valve cavity 4 is also filled with hydraulic oil, it acts on the main spool 3 to close the main valve port. As the current changes, the pressure in the pilot cavity changes, and the pressure in the main valve cavity 4 will change accordingly, thereby changing the position of the main spool 3 to realize the adjustment of the overflow pressure of the main spool 3.

[0040] The oil inlet ports for the compression stroke and the recovery stroke are opposite, and the positions where the oil inlet pressure acts will be different. Specifically, such as Figure 5As shown in the figure, during the compression stroke, the bottom of the valve sleeve 1 is the oil inlet, and the side oil port is the oil outlet. The hydraulic oil in the compression chamber (oil inlet) will first open the first one-way valve 6 on the left side of the main valve core 3 and enter the main valve chamber 4; then it flows into the pilot chamber through the pilot valve hole 18 of the lower seat of the pilot valve. As described above, when the current is zero, the oil will only flow to the oil outlet through the oil outlet small hole 19 of the upper valve seat 15. Since the lower end of the damping valve is at a high pressure at this time, the third one-way valve 13 on the upper left side of the valve sleeve 1 is closed, and the oil behind the pilot chamber can only flow out to the liquid outlet through the fourth one-way valve 14 on the right side; as the flow rate and pressure in the compression chamber increase, the oil pressure on the main valve core 3 will cause the main valve core 3 to move upward. As the main valve core 3 gradually opens, more oil flows out through the gap between the lower end of the main valve core 3 and the side wall of the installation chamber 2 to the (oil outlet) restoration chamber; when the current increases, the armature 27 assembly will push the valve ball 17 downward, thereby changing the throttling area between the valve ball 17 and the upper and lower valve seats 16, and thus adjusting the damping size.

[0041] In the above structure, since the first one-way valve 6 is designed in the main valve, the compression chamber is both the main oil chamber, and the pressure oil enters the intermediate chamber through the one-way valve. The hydraulic oil volume passing through this one-way valve is small, which can reduce the size of the one-way valve. At the same time, since most of the pressure oil flows out through the opening between the main valve core 3 and the valve sleeve 1, the CDC valve has a larger flow range, and the overall structure is more compact; in addition, the fourth one-way valve 14 only controls the outflow of the hydraulic oil of the pilot valve, and the main valve oil circuit is not affected by the fourth one-way valve 14. This makes the volume of the liquid flowing into the fourth one-way valve 14 small, easy to control, with a fast response speed, and can also reduce the size of the one-way valve, thereby reducing the overall size of the CDC valve.

[0042] As Figure 6 The oil circuit diagram during the restoration process is shown as follows: At this time, the side oil port is the oil inlet, and the bottom oil port is the oil outlet; the hydraulic oil in the restoration chamber (oil inlet) will first open the second one-way valve 7 on the right side of the main valve core 3 and enter the main valve chamber 4; then it flows into the pilot chamber through the pilot valve hole 18 of the lower valve seat 16; similarly, as described above, when the current is zero, the oil will only flow to the oil outlet through the oil outlet small hole 19 of the upper valve seat 15. Since the side of the damping valve is at a high pressure at this time, the fourth one-way valve 14 on the upper right side of the valve sleeve 1 is closed, and the oil behind the pilot chamber can only flow out to the (oil outlet) compression chamber through the third one-way valve 13 on the left side; as the flow rate and pressure in the restoration chamber increase, the pressure on the main valve core 3 will also cause the main valve core 3 to move upward, so that more oil flows out through the gap between the lower end of the main valve core 3 and the side wall of the installation chamber 2 to the compression chamber; when the current increases, the armature 27 assembly will push the ball valve, thereby changing the throttling area between the valve ball 17 and the upper and lower valve seats 16, and thus adjusting the damping size.

[0043] Similarly, during the restoration process, the second one-way valve 7 is designed inside the main valve. The restoration chamber is also the main oil chamber. The pressure oil enters the intermediate chamber through the second one-way valve 7. The hydraulic oil volume passing through the second one-way valve 7 is small, which can reduce the size of the one-way valve. At the same time, since most of the pressure oil flows out through the opening between the main spool 3 and the valve sleeve 1 and is not restricted by the one-way valve, the CDC valve has a larger flow range and makes the overall structure more compact. Additionally, the third one-way valve 13 only controls the outflow of the hydraulic oil of the pilot valve, and the main valve oil circuit is not affected by the third one-way valve 13. This makes the volume of the liquid flowing into the third one-way valve 13 during restoration small, easy to control, with a fast response speed, and can also reduce the size of the one-way valve, thereby reducing the overall size of the CDC valve.

[0044] On the other hand, as Figure 4 shown, a concave upper sealing chamber 22 is provided on the lower end surface of the upper valve seat 15, a concave lower sealing chamber 23 is provided on the upper end surface of the lower valve seat 16, and pilot valve holes 18 are opened at the bottoms of both the upper sealing chamber 22 and the lower sealing chamber 23; a spring hole 24 for accommodating the pilot return spring 20 is also provided at the bottom of the lower sealing chamber 23. A ring-shaped elastic piece 29 is provided near the lower valve seat 16 in the installation chamber 2, and the elastic force of the elastic piece 29 is less than that of the main return spring 5; the outer end in the radial direction of the elastic piece 29 is fitted with the installation chamber 2, and there is a movable space between the inner end in the radial direction of the elastic piece 29 and the lower valve seat 16; the upper end of the main return spring 5 abuts against the lower surface of the inner end of the elastic piece 29. After such a setting, during the compression or restoration stroke, when the main spool 3 is just about to open, the force to be overcome is not the elastic force of the main return spring 5 but the elastic force of the elastic piece 29. Since the elastic force of the elastic piece 29 is small, the opening pressure is small and the response speed is fast, making the reaction of the entire valve group more sensitive, that is, the damping adjustment of the entire solenoid valve is more flexible and precise; as the opening pressure gradually increases, the main return spring 5 begins to be slowly compressed to achieve the full opening of the main spool 3.

[0045] As Figure 4 shown, a connecting column 30 is formed at the lower end of the lower valve seat 16. The pilot valve hole 18 and the spring hole 24 of the lower valve seat 16 are both axially provided on the connecting column 30; the connecting column 30 is movably inserted into the inner hole of the elastic piece 29, and the upper end of the main return spring 5 is slidably sleeved outside the connecting column 30, enabling the main return spring 5 to achieve circumferential limitation and ensuring the smoothness of the telescopic deformation of the main return spring 5.

[0046] Additionally, as Figure 2 shown, a limit ring 31 is fitted at the opening end of the installation chamber 2. The upper end surface of the limit ring 31 abuts against the lower end surface of the main spool 3. Specifically, the limit ring 31 is connected to the opening end of the installation chamber 2 in an interference fit manner to achieve the axial limitation of the main spool 3 and prevent the main spool 3 from disengaging from the installation chamber 2 under the elastic force of the main return spring 5.

[0047] The solenoid valve structure of the present invention has the following effects:

[0048] 1. When the solenoid valve is de-energized, the valve ball 17 will be pushed by the pilot return spring 20 and hydraulic pressure to the sealing chamfer of the upper valve seat 15. The oil in the pilot chamber will only flow to the oil outlet passage 8 through the oil outlet small hole 19. This mode is defined as the 0 mA failure mode, that is, a relatively large damping force will still be maintained in the case of vehicle failure, improving the safety of the vehicle; and the area of the oil outlet small hole 19 can be adjusted to match the requirements of different vehicles.

[0049] 2. The pressure in the pilot chamber is adjusted by the position of the valve ball 17; the pilot valve is involved in the damping adjustment process during both the compression and recovery strokes, greatly reducing the requirement for electromagnetic force on the damping adjustment valve, that is, a smaller electromagnetic force can be used to obtain a wider pressure-flow adjustment range.

[0050] 3. The hydraulic oil circuits for the compression process and the recovery process are realized through the four check valves on the main spool 3 and the valve sleeve 1.

[0051] 4. The cooperation between the conical surfaces on the upper valve seat 15 and the lower valve seat 16 of the pilot valve and the ball valve is used to realize the change of the throttle orifice of the pilot valve under different currents, thereby adjusting the pressure in the main valve chamber 4 and realizing damping adjustment.

[0052] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will all fall within the protection scope of the present invention.

Claims

1. A shock absorber damping adjustable solenoid valve, characterized in that: It includes a valve sleeve (1). An installation cavity (2) with an opening facing downwards is provided at the lower end of the valve sleeve (1), and the opening end of the installation cavity (2) communicates with an oil inlet passage. A main valve core (3) is slidably fitted in the installation cavity (2) so that a main valve cavity (4) is formed between the main valve core (3) and the bottom of the installation cavity (2). A main return spring (5) is provided between the main valve core (3) and the bottom of the installation cavity (2). A first one-way valve (6) for communicating the main valve cavity (4) with the oil inlet passage and a second one-way valve (7) for communicating the main valve cavity (4) with an oil outlet passage (8) are arranged on the main valve core (3); an oil outlet passage (8) communicating with the installation cavity (2) is opened on the side wall of the valve sleeve (1). A housing (9) is sleeved on the upper end of the valve sleeve (1). An oil outlet gap (10) is left between the bottom of the housing (9) and the top of the valve sleeve (1). A first oil passage (11) for communicating the oil inlet passage with the oil outlet gap (10) and a second oil passage for communicating the oil outlet passage (8) with the oil outlet gap (10) are respectively arranged on the valve sleeve (1). A third one-way valve (13) and a fourth one-way valve (14) are respectively arranged in the first oil passage (11) and the second oil passage; A pilot valve for communicating the main valve cavity (4) with the oil outlet gap (10) is further arranged at the bottom of the installation cavity (2). The pilot valve includes an upper valve seat (15), a lower valve seat (16) and a valve ball (17). A pilot cavity is formed between the upper valve seat (15) and the lower valve seat (16). Pilot valve holes (18) for communicating the main valve cavity (4) with the pilot cavity and communicating the pilot cavity with the oil outlet gap (10) are respectively arranged in the middle parts of the upper valve seat (15) and the lower valve seat (16); An oil outlet small hole (19) is further arranged on the upper valve seat (15). A pilot return spring (20) is arranged on the lower valve seat (16) so that the valve ball (17) always has a tendency to move upwards to seal the upper valve seat (15); A push rod (21) and an electromagnetic drive assembly for driving the push rod (21) to move up and down are arranged at the upper end of the housing (9). When the electromagnetic drive assembly is powered on, the push rod (21) can move downwards so that the valve ball (17) moves downwards after overcoming the elastic force of the pilot return spring (20) and the hydraulic pressure; During compression, a small part of the oil in the oil inlet passage enters the pilot valve from the first one-way valve (6) and then flows into the oil outlet passage (8) through the fourth one-way valve (14). Under the action of the pilot valve, the main valve core (3) opens, and most of the oil enters the oil outlet passage (8) from the gap between the main valve core (3) and the installation cavity (2); During restoration, a small part of the oil in the oil outlet passage (8) enters the pilot valve from the second one-way valve (7) and then flows back to the liquid inlet passage through the third one-way valve (13). Under the action of the pilot valve, the main valve core (3) opens, and most of the oil flows back to the oil outlet passage (8) from the gap between the main valve core (3) and the installation cavity (2).

2. The shock absorber damping adjustable solenoid valve according to claim 1, characterized in that: The lower end face of the upper valve seat (15) is provided with a concave upper sealing cavity (22), the upper end face of the lower valve seat (16) is provided with a concave lower sealing cavity (23), and the pilot valve holes (18) are opened at the bottoms of the upper sealing cavity (22) and the lower sealing cavity (23); a spring hole (24) for accommodating a pilot return spring (20) is further provided at the bottom of the lower sealing cavity (23).

3. The shock absorber damping adjustable solenoid valve according to claim 2, characterized in that: The electromagnetic drive assembly includes a coil (25), a magnetic conduction tube (26) and an armature (27). The magnetic conduction tube (26) is a sleeve with an open lower part. The outer ring of the sleeve is fitted on the inner wall of the coil (25), and the outer wall of the coil (25) is connected to the housing (9); the armature (27) is slidably fitted in the sleeve in the vertical direction, and the upper end of the ejector rod (21) is fixedly connected to the armature (27); a sealing cover plate (28) is further provided at the top of the housing (9).

4. The shock absorber damping adjustable solenoid valve according to claim 3, characterized in that: The upper side wall of the housing (9) surrounds the outside of the coil (25), and the housing (9) is made of a soft magnetic material so that a magnetic closed loop can be formed between the housing (9) and the coil (25).

5. The shock absorber damping adjustable solenoid valve according to claim 2 or 3, characterized in that: A circular elastic sheet (29) is provided at a position in the installation cavity (2) close to the lower valve seat (16), and the elastic force of the elastic sheet (29) is less than the elastic force of the main return spring (5); the outer end of the elastic sheet (29) in the radial direction is fitted with the installation cavity (2), and there is a movable space between the inner end of the elastic sheet (29) in the radial direction and the lower valve seat (16); the upper end of the main return spring (5) abuts against the lower surface of the inner end of the elastic sheet (29).

6. The shock absorber damping adjustable solenoid valve according to claim 5, characterized in that: A connecting column (30) is formed at the lower end of the lower valve seat (16). The pilot valve hole (18) and the spring hole (24) of the lower valve seat (16) are both axially arranged on the connecting column (30); the connecting column (30) movably passes through the inner hole of the elastic sheet (29), and the upper end of the main return spring (5) is slidably sleeved on the outside of the connecting column (30).

7. The shock absorber damping adjustable solenoid valve according to claim 1, characterized in that: A limiting ring is fitted at the open end of the installation cavity (2), and the upper end face of the limiting ring abuts against the lower end face of the main valve core (3).

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