Electromagnetic valve for a shock absorber and shock absorber

Abstract

This utility model relates to an electromagnetic valve for a shock absorber and a shock absorber. It includes: an outer valve sleeve containing a pilot valve chamber; a pilot valve core mounted within the pilot valve chamber and movable axially within it; and an electromagnetic coil, whose energization or de-energization controls the position of the pilot valve core. When the electromagnetic coil is de-energized, the pilot valve core is in a failed position. In the failed position, an annular flow path is formed between the pilot valve chamber and the pilot valve core. At least a portion of the annular flow path is a variable cross-section annular flow path, and the longitudinal section of the variable cross-section annular flow path has a waist-shaped design, contracting in the middle and expanding at both ends along the axial direction. This waist-shaped design improves the consistency of damping force in the electromagnetic valve and the shock absorber including the electromagnetic valve.

Description

Technical Field

[0001] This utility model relates to the field of electromagnetic control valves, and more specifically to electromagnetic valves used in shock absorbers. Background Technology

[0002] The hydraulic medium damper includes a solenoid valve for controlling the flow of the medium therein. The solenoid valve controls the damping force of the damper through electromagnetic drive. Figure 1 The graph shows the damping force of a shock absorber with a conventional solenoid valve as a function of iterations, where the solenoid valve is in failure mode. Figure 1 As shown, when the solenoid valve is in failure mode, the damping force of the shock absorber is inconsistent, with a deviation of up to 275%, which affects the performance stability of the shock absorber. Utility Model Content

[0003] The purpose of this invention is to provide a solenoid valve for shock absorbers that can improve the consistency of damping force.

[0004] One aspect of this utility model provides an electromagnetic valve for a shock absorber, comprising: an outer valve sleeve having a pilot valve chamber therein; a pilot valve core installed in the pilot valve chamber and capable of moving axially within the pilot valve chamber; and an electromagnetic coil, wherein the position of the pilot valve core is controlled by energizing or de-energizing the electromagnetic coil, and the pilot valve core is in a failed position when the electromagnetic coil is de-energized, wherein at the failed position, an annular flow path is formed between the pilot valve chamber and the pilot valve core, at least a portion of the annular flow path is a variable cross-section annular flow path, and the longitudinal section of the variable cross-section annular flow path has an waist-shaped shape that contracts in the middle and expands at both ends along the axial direction.

[0005] According to an embodiment of the present invention, the pilot valve chamber has a variable cross-section chamber, which has an axially constricted middle and expanded ends in a waist-shaped form, and the outer peripheral surface of the pilot valve core is a cylindrical surface.

[0006] According to an embodiment of the present invention, the cross-section of the variable cross-section chamber consists of a straight line segment extending along the axial direction and two oblique line segments connected to the two ends of the straight line segment and inclined relative to the axial direction.

[0007] According to an embodiment of this utility model, the slopes and lengths of the two oblique line segments are the same.

[0008] According to an embodiment of the present invention, the pilot valve core has a variable cross-section portion, which has a drum-shaped shape that expands in the middle along the axial direction and contracts at both ends, and the inner circumferential surface of the pilot valve chamber is a cylindrical surface.

[0009] According to an embodiment of the present invention, the cross-sectional line of the outer peripheral surface of the variable cross-section portion is a straight line segment extending along the axial direction and two oblique line segments connected to the two ends of the straight line segment and inclined relative to the axial direction.

[0010] According to an embodiment of this utility model, the slopes and lengths of the two oblique line segments are the same.

[0011] According to an embodiment of the present invention, the pilot valve chamber has a variable cross-section chamber, which has an axially constricted middle section and an extended end section. The pilot valve core has a variable cross-section section, which has an axially extended middle section and an extended end section. At the failure position, the variable cross-section chamber and the variable cross-section section face each other.

[0012] According to an embodiment of the present invention, the outer valve sleeve is provided with a radial flow path, which is connected to a variable cross-section annular flow path. In the failure position, the medium in the pilot valve chamber flows out of the outer valve sleeve through the variable cross-section annular flow path and the radial flow path.

[0013] Another aspect of this utility model provides a shock absorber, which includes a solenoid valve for a shock absorber according to any of the above embodiments.

[0014] At least a portion of the annular flow path of the solenoid valve of this invention is a variable cross-section annular flow path, and the longitudinal section of the variable cross-section annular flow path has a waist-shaped shape that contracts in the middle and expands at both ends along the axial direction X. Compared with the flared design of the prior art, on the one hand, this waist-shaped design improves the concentricity of the outer valve sleeve and the pilot valve core; on the other hand, the convex feature of this waist-shaped design changes the flow path of the medium between the outer valve sleeve and the pilot valve core, which can make the medium distribution more uniform, thereby indirectly playing a role in pressure equalization and further improving the concentricity of the pilot valve core and the outer valve sleeve. Thus, the consistency of damping force in failure mode is improved. After testing, the damping force consistency deviation of this invention is reduced from 275% in the prior art to 20%. This means that even if the system fails, the performance of the shock absorber will not be significantly different, making it more stable and reliable. In active mode, the oil drain channel of the pilot valve changes, and the convex feature of this design will not cause turbulence or local pressure fluctuations in the hydraulic oil, thus not affecting the stability of the system in active mode. Furthermore, this invention optimizes the structure of existing technologies, thereby improving the consistency of damping force without increasing costs. Attached Figure Description

[0015] Figure 1 A graph showing the damping force of a shock absorber with a conventional solenoid valve as a function of the number of iterations is presented, where the solenoid valve is in failure mode.

[0016] Figure 2 A longitudinal sectional view of a solenoid valve according to an embodiment of the present invention is shown.

[0017] Figure 3 A partial cross-sectional view of a solenoid valve according to an embodiment of the present invention is shown.

[0018] Figure 4A A schematic diagram showing the medium path P1 of the solenoid valve according to an embodiment of the present invention is shown.

[0019] Figure 4B A schematic diagram showing the medium path P2 of the solenoid valve according to an embodiment of the present invention is shown.

[0020] Figure 5 A partial cross-sectional view of a prior art solenoid valve is shown.

[0021] Figure 6A , 6B Figures 6C and 6C respectively show the cross-sectional lines of the variable cross-section chamber and the outer peripheral surface of the variable cross-section portion of the solenoid valve according to an embodiment of the present invention. Detailed Implementation

[0022] The embodiments of this utility model are described in detail below based on the accompanying drawings.

[0023] In this invention, unless otherwise specified, axial, radial, and circumferential refer to the axial, radial, and circumferential directions of the solenoid valve, respectively. The terms "first," "second," "third," etc., are used to describe various structures, but these structures should not be limited to these terms. These terms are only used to distinguish structures of the same type from each other and do not indicate a specific order or degree of importance. In fact, the expressions "first," "second," "third," etc., are completely interchangeable.

[0024] Figure 2 A longitudinal sectional view of a solenoid valve according to an embodiment of the present invention is shown. Figure 2 As shown, the solenoid valve includes a solenoid subassembly and a valve body subassembly. The solenoid subassembly is the power unit of the solenoid valve, and the valve body subassembly is the actuating part of the solenoid valve.

[0025] The electromagnetic subassembly is the power unit of the solenoid valve, comprising a housing 1, an electromagnetic coil 2, an armature 3, and a front magnetic pole 4. The electromagnetic coil 2 is installed within the cavity formed by the housing 1 and generates an electromagnetic field. The armature 3, typically made of magnetic material, responds to the magnetic field generated by the electromagnetic coil 2, displacing under the influence of electromagnetic force. The central part of the armature 3 is the armature shaft 31, which serves as a guide and support, ensuring that the armature 3 can move smoothly and accurately along the axial direction X under the influence of electromagnetic force. The front magnetic pole 4 is located within the housing 1 and close to the valve body subassembly.

[0026] Figure 3 A partial cross-sectional view of a solenoid valve according to an embodiment of the present invention is shown. Figure 3 As shown, the valve body subassembly includes a pilot valve 5, a main valve 6, and an outer valve sleeve 7. The pilot valve 5 has a pilot valve core 51, a pilot spring 52, and a pilot valve seat 53. The main valve 6 has a main valve core 61, a main valve spring 62, and a main valve seat 63.

[0027] The outer valve sleeve 7 contains a pilot valve chamber 71, and the pilot valve core 51 is installed inside the pilot valve chamber 71 and can move along the axial direction X within the pilot valve chamber 71. The position of the pilot valve core 51 can be controlled by energizing or de-energizing the electromagnetic coil 2. The two axial ends of the pilot spring 52 abut against the wall of the pilot valve chamber 71 and the pilot valve core 51, respectively, to apply a biasing force to the pilot valve core 51 to move it away from the pilot valve seat 53. A first cavity 72 is formed between the pilot valve core 51 and the pilot valve seat 53. The pilot valve core 51 is provided with a plurality of pilot valve oil outlet holes 511 extending along the axial direction X, and the plurality of pilot valve oil outlet holes 511 are arranged at equal intervals along the circumference.

[0028] The outer valve sleeve 7 contains a main valve chamber 73, and the main valve core 61 is installed within the main valve chamber 73 and is movable within the main valve chamber 73 along the axial direction X. The main valve chamber 73 is connected to the pilot valve chamber 71 via a connecting flow path 74 extending along the axial direction X. The two axial ends of the main valve spring 62 abut against the wall of the main valve chamber 73 and the main valve core 61, respectively, to apply a biasing force to the main valve core 61 to move it away from the pilot valve core 51.

[0029] The main valve core 61 and the main valve seat 63 are arranged coaxially. The main valve seat 63 has a main valve inlet hole 632 that runs through along the axial direction X, and the outer valve sleeve 7 is provided with a radially through main valve outlet hole 75. When the main valve core 61 moves away from the main valve seat 63, the main valve outlet hole 75 gradually opens; conversely, when the main valve core 61 moves closer to the main valve seat 63, the main valve outlet hole 75 gradually closes, thereby realizing the adjustment of the damping force of the shock absorber.

[0030] The main valve core 61 includes a valve disc 611 and a column 612 arranged coaxially. The first end of the column 612 extends into the pilot valve chamber 71, and the second end of the column 612, opposite to the first end, is connected to the valve disc 611 within the main valve chamber 73. The first end of the column 612 forms a pilot valve seat 53. The valve disc 611 has a first flow path 611a extending axially (X), and the column 612 has a second flow path 612a extending axially (X). The first flow path 611a and the second flow path 612a are connected, allowing the medium to enter the first cavity 72 from the main valve inlet port 632 through the first flow path 611a and the second flow path 612a. The medium in this text can be a gaseous medium or a liquid medium such as hydraulic oil. An annular second cavity 613 is formed between the column 612 and the outer valve sleeve 7, and the second cavity 613 is connected to the second flow path 612a through a third flow path 612b formed in the column 612.

[0031] The outer valve sleeve 7 has a radial flow path 76 at its end near the solenoid coil 2, which is connected to the pilot valve chamber 71. There can be multiple radial flow paths 76, for example, four, arranged at equal intervals along the circumference. The outer circumferential surface of the outer valve sleeve 7 has an axial flow path 77, which is connected to the radial flow path 76. The medium in the pilot valve chamber 71 can flow out of the solenoid valve through the radial flow path 76 and the axial flow path 77.

[0032] When the electromagnetic coil 2 is de-energized, that is, in the failure mode, the pilot spring 52 applies a spring force to the pilot valve core 51, pushing the pilot valve core 51 against the end face of the front magnetic pole 4. At this time, the pilot valve core 51 is in the failure position. In this failure position, the pilot valve outlet 511 is blocked by the front magnetic pole 4, and an annular flow path 8 is provided between the pilot valve core 51 and the pilot valve chamber 71. Since the pilot valve outlet 511 is blocked, the medium in the first cavity 72 enters the radial flow path 76 through the annular flow path 8, and then flows out of the solenoid valve through the axial flow path 77, such as... Figure 4A The path P1 is shown. This process creates a certain back pressure on the main valve core 61, thereby providing the required damping force. This ensures that the shock absorber maintains a certain damping function even in failure mode, maintaining the stability and safety of the system.

[0033] When the electromagnetic coil 2 is energized, the electromagnetic force on the armature 3 gradually increases with the increase of the current. When the electromagnetic force is sufficient to overcome the elastic force of the pilot spring 52 and the fluid force on the pilot valve core 51, the armature 3 begins to move axially towards the pilot valve core 51. The armature shaft 31 abuts against the pilot valve core 51 and pushes it away from the failure position, causing it to move towards the pilot valve seat 53. At this time, the front magnetic pole 4 no longer blocks the pilot valve outlet hole 511, and the medium in the first cavity 72 flows out of the solenoid valve in sequence through the pilot valve outlet hole 511, the radial flow path 76, and the axial flow path 77, as shown. Figure 4B The path is shown in P2. When the current of the electromagnetic coil 2 reaches 0.3A or more, it enters the active mode, and the pilot valve core 51 completely abuts against the pilot valve seat 53. At this time, the medium pressure in the second chamber 613 increases, causing the main valve core 61 to move away from the pilot valve core 51, and the main valve oil outlet 75 gradually closes, thereby achieving normal damping force adjustment.

[0034] Figure 5 A partial cross-sectional view of a prior art solenoid valve is shown. (e.g.) Figure 5 As shown, in the prior art, the pilot valve chamber 71' of the solenoid valve has a flared opening at its end, and the pilot valve core 51' has a cylindrical outer circumferential surface. The inventor has discovered that the flared opening in the prior art is the cause of poor consistency in damping force.

[0035] In view of this, in order to solve the problem of poor damping force consistency, the inventors, after in-depth research, designed a solenoid valve for a shock absorber. In this invention, when the pilot valve core 51 is in the failed position, at least a portion of the annular flow path 8 is a variable cross-section annular flow path, and the longitudinal section of the variable cross-section annular flow path has a waist-shaped shape that contracts in the middle and expands at both ends along the axial direction X. In this paper, the longitudinal section is a cross-sectional view obtained by cutting along the axial direction X of the annular flow path 8. The waist-shaped shape can be symmetrical or asymmetrical about the axial direction X.

[0036] Compared to the existing bell-shaped design, the waist-shaped design of this invention improves the concentricity of the outer valve sleeve 7 and the pilot valve core 51. Furthermore, the protruding features of this waist-shaped design alter the flow path of the medium between the outer valve sleeve 7 and the pilot valve core 51, resulting in a more uniform medium distribution and indirectly contributing to pressure equalization, further enhancing the concentricity of the pilot valve core 51 and the outer valve sleeve 7. This improves the consistency of damping force under failure modes. Testing showed that the damping force consistency deviation of this invention was reduced from 275% in the prior art to 20%. This means that even if the system fails, the shock absorber's performance will not differ significantly, resulting in greater stability and reliability. In active mode, the oil drain channel of the pilot valve 5 changes; the protruding features of this design do not cause turbulence or local pressure fluctuations in the hydraulic oil, thus not affecting the system's stability in active mode. Moreover, this invention optimizes the structure of the prior art, thereby improving the consistency of damping force without increasing costs.

[0037] Figure 6A , 6B Figures 6C and 6C respectively show the cross-sectional lines of the variable cross-section chamber and the outer peripheral surface of the variable cross-section portion of the solenoid valve according to an embodiment of the present invention. It should be understood that the figures are merely schematic diagrams, their main purpose being to illustrate the shape features of the relevant structures of the present invention in a simplified form to facilitate understanding of the technical concept of the present invention. These figures are not drawn to actual scale or precise dimensions, and therefore should not be construed as a precise description of specific embodiments of the present invention. For example, Figures 6A to 6C The tilt angles and length ratios of the various segments (upper and lower diagonal segments and the middle straight segment) of the related structures are for illustrative purposes only. Their purpose is to highlight the overall shape characteristics of the structure, not to accurately reflect the actual geometric parameters. Precise inferences or measurements should not be made based on the angles and length ratios shown in the diagram. For ease of understanding, the tilt angles have been intentionally exaggerated and do not reflect the true tilt angles in the actual product or structure.

[0038] In one embodiment, such as Figure 6AAs shown, the pilot valve chamber 71 has a variable cross-section chamber 711, which has a waist-shaped shape that tapers in the middle and expands at both ends along the axial direction X. The outer circumferential surface of the pilot valve core 51 is cylindrical. In this case, the waist-shaped design can be achieved by simply changing the shape of the pilot valve chamber 71. The cross-sectional line 712 of the variable cross-section chamber 711 consists of a straight segment extending along the axial direction X and two oblique segments connected to the two ends of the straight segment and inclined relative to the axial direction X. That is, the inner surfaces of the two end cavities of the variable cross-section chamber 711 are conical surfaces, and the inner surface of the middle cavity is cylindrical. The slope and length of the two oblique segments are the same, and this symmetrical design further improves concentricity and stability. However, this invention is not limited to the above-mentioned symmetrical design. In some application scenarios, the slope and length of the two oblique segments can also be different. Those skilled in the art can flexibly adjust and optimize the slope and length of the oblique segments according to actual needs. The straight segment and the oblique segment can be connected by a smooth transition curve. It should be understood that the shape of the section line 712 of the variable cross section chamber 711 is not limited to this. For example, it can also be a curve, such as an ellipse or an hourglass line.

[0039] In another embodiment, such as Figure 6B As shown, the pilot valve core 51 has a variable cross-section portion 512, which has a drum-shaped form that expands in the middle and contracts at both ends along the axial direction X, and the inner circumferential surface of the pilot valve chamber 71 is cylindrical. In this case, the waist-shaped design can be achieved by only changing the shape of the pilot valve core 51. The cross-sectional line 513 of the outer circumferential surface of the variable cross-section portion 512 consists of a straight segment extending along the axial direction X and two oblique segments connected to the two ends of the straight segment and inclined relative to the axial direction X. That is, the outer surfaces of the two ends of the variable cross-section portion 512 are conical surfaces, and the outer surface of the middle portion is cylindrical. The slope and length of the two oblique segments are the same, and this symmetrical design further improves concentricity and stability. However, this invention is not limited to the above-mentioned symmetrical design. In some application scenarios, the slope and length of the two oblique segments can also be different. Those skilled in the art can flexibly adjust and optimize the slope and length of the oblique segments according to actual needs. The straight segment and the oblique segment can be connected by a smooth transition curve. It should be understood that the shape of the section line 513 on the outer peripheral surface of the variable cross section 512 is not limited to this. For example, it can also be a curve, such as an ellipse or an hourglass line.

[0040] In another embodiment, such as Figure 6CAs shown, the pilot valve chamber 71 has a variable cross-section chamber 711, which has a waist-shaped shape that tapers in the middle and expands at both ends along the axial direction X. The pilot valve core 51 has a variable cross-section portion 512, which has a drum-shaped shape that expands in the middle and tapers at both ends along the axial direction X. At the failure position, the variable cross-section chamber 711 and the variable cross-section portion 512 face each other. In this case, by changing the shapes of both the pilot valve core 51 and the pilot valve chamber 71, a waist-shaped design can be achieved. The variable cross-section chamber 711 and the variable cross-section portion 512 can be... Figure 6A and Figure 6B As shown in the embodiment, it is constructed as described here, so it will not be described again.

[0041] The variable cross-section annular flow path is connected to the radial flow path 76 of the outer valve sleeve 7. At the failure position, the medium flows out of the pilot valve chamber 71 from the outer valve sleeve 7 through the variable cross-section annular flow path and the radial flow path 76. However, the position of the variable cross-section annular flow path is not limited to this; for example, it can be spaced apart from the radial flow path 76 along the axial direction X by a certain distance.

[0042] The axial length of the variable cross-section annular flow path (e.g., 0.2mm-0.4mm) can be less than the axial length of the outer peripheral surface of the pilot valve core 51. The pilot valve chamber 71 may have an additional variable cross-section chamber, which is the portion of the pilot valve chamber 71 that does not face the outer peripheral surface of the pilot valve core 51 at the failure position. The cross-section of this additional variable cross-section chamber changes along the axial direction X, serving to guide the pilot valve core 51 at the non-failure position. The variable cross-section chamber 711 is connected to the additional variable cross-section chamber, and at the connection position, the section line 712 of the variable cross-section chamber 711 and the section line of the additional variable cross-section chamber extend in the same direction, meaning their shape changes are continuous.

[0043] An embodiment of this utility model also provides a shock absorber, which includes the solenoid valve described in the above embodiment. With this configuration, the shock absorber provided in this embodiment can improve the consistency of damping force. The derivation process of this beneficial effect is largely similar to the derivation process of the beneficial effect brought by the solenoid valve described above, and will not be repeated here.

[0044] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

[0045] List of reference numerals

[0046] 1. Outer casing; 2. Electromagnetic coil; 3. Armature; 31. Armature shaft; 4. Front magnetic pole;

[0047] 5. Pilot valve; 51, 51', Pilot valve core; 511, Pilot valve outlet; 512, Variable cross-section section; 513, Section line of the outer peripheral surface of the variable cross-section section; 52, Pilot spring; 53, Pilot valve seat;

[0048] 6. Main valve; 61. Main valve core; 611. Valve disc; 611a. First flow path; 612. Column;

[0049] 612a, Second flow path; 612b, Third flow path; 613, Second cavity; 62, Main valve spring;

[0050] 63. Main valve seat; 632. Main valve oil inlet port;

[0051] 7. Outer valve sleeve; 71, 71', pilot valve chamber; 711, variable cross-section chamber; 712, cross-sectional line of variable cross-section chamber; 72, first cavity; 73, main valve chamber; 74, connecting flow path; 75, main valve oil outlet; 76, radial flow path; 77, axial flow path; 8, annular flow path; X, axial direction.

Claims

1. An electromagnetic valve for a shock absorber, characterized by, include: An outer valve sleeve (7) is provided inside a pilot valve chamber (71); A pilot valve core (51) is mounted within the pilot valve chamber (71) and is movable axially (X) within the pilot valve chamber (71); and An electromagnetic coil (2) controls the position of the pilot valve core (51) by energizing or de-energizing the electromagnetic coil (2). When the electromagnetic coil (2) is de-energized, the pilot valve core (51) is in a failed position. At the failure location, an annular flow path (8) is formed between the pilot valve chamber (71) and the pilot valve core (51). At least a portion of the annular flow path (8) is a variable cross-section annular flow path, and the longitudinal section of the variable cross-section annular flow path has a waist-shaped shape that contracts in the middle and expands at both ends along the axial direction (X).

2. The solenoid valve for a shock absorber according to claim 1, characterized in that, The pilot valve chamber (71) has a variable cross-section chamber (711), which has a waist-shaped shape that contracts in the middle and expands at both ends along the axial direction (X), and the outer peripheral surface of the pilot valve core (51) is a cylindrical surface.

3. The solenoid valve for a shock absorber according to claim 2, characterized in that, The cross-section line (712) of the variable cross-section chamber (711) consists of a straight line segment extending along the axial direction (X) and two oblique line segments connected to the two ends of the straight line segment and inclined relative to the axial direction (X).

4. The solenoid valve for a shock absorber according to claim 3, characterized in that, The two oblique line segments have the same slope and length.

5. The solenoid valve for a shock absorber according to claim 1, characterized in that, The pilot valve core (51) has a variable cross-section portion, which has a drum-shaped shape that expands in the middle and contracts at both ends along the axial direction (X), and the inner circumferential surface of the pilot valve chamber (71) is a cylindrical surface.

6. The solenoid valve for a shock absorber according to claim 5, characterized in that, The cross-sectional line (513) of the outer peripheral surface of the variable cross-section portion (512) consists of a straight line segment extending along the axial direction (X) and two oblique line segments connected to the two ends of the straight line segment and inclined relative to the axial direction (X).

7. The solenoid valve for a shock absorber according to claim 6, characterized in that, The two oblique line segments have the same slope and length.

8. The solenoid valve for a shock absorber according to claim 1, characterized in that, The pilot valve chamber (71) has a variable cross-section chamber (711), which has a waist-shaped shape that tapers in the middle and expands at both ends along the axial direction (X). The pilot valve core (51) has a variable cross-section portion (512), which has a drum-shaped shape that expands in the middle and tapers at both ends along the axial direction (X). At the failure position, the variable cross-section chamber (711) and the variable cross-section portion (512) face each other.

9. The solenoid valve for a shock absorber according to any one of claims 1 to 8, characterized in that, The outer valve sleeve (7) is provided with a radial flow path (76), which is connected to the variable cross-section annular flow path. At the failure position, the medium in the pilot valve chamber (71) flows out of the outer valve sleeve (7) through the variable cross-section annular flow path and the radial flow path (76).

10. A shock absorber characterized by Includes a solenoid valve for a shock absorber according to any one of claims 1 to 9.

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