Continuous hydraulic damping force adjusting valve
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- ASTEMO LTD
- Filing Date
- 2026-01-13
- Publication Date
- 2026-07-30
Smart Images
Figure JP2026000632_30072026_PF_FP_ABST
Abstract
Description
Valve for continuously adjusting hydraulic damping force
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 749,155, filed Jan. 24, 2025, which is incorporated herein by reference.
[0002] To enhance ride comfort, vehicle stability, and vehicle maneuverability, various types of dampers can be used in a vehicle suspension system. Although a conventional suspension system may employ a hydraulic (oil pressure) damper, the conventional hydraulic (oil pressure) damper has limitations in adapting to changing road conditions and driving behaviors. For example, existing semi-active damper technologies such as semi-active hydraulic (oil pressure) dampers (SAHDs) face several challenges, including limitations in the accuracy of damping force adjustment, relatively slow response times to changes in road conditions, and inefficiencies in the damper itself that may reduce ride quality and vehicle stability.
[0003] In some implementations, the valve includes a valve body having a central axis. A valve surface is disposed at a first end of the valve body, and the valve surface includes an outer surface and an inner surface that contact each other at a top where a circular valve seating surface is disposed. The inner surface has a shape of a first frustum of a cone that converges in a first direction toward the valve body, and the outer surface has a shape of a second frustum of a cone that converges in a second direction away from the valve body. The inner surface has a first angle with respect to the central axis, and the outer surface extends from a periphery of the valve body and has a second angle with respect to a line parallel to the central axis. The first angle of the inner surface is greater than the second angle of the outer surface.
[0004] Perspective view of a pilot valve of an embodiment according to some implementations.
[0005] Cross-sectional view of the pilot valve according to some implementations.
[0006] Cross-sectional view of a pilot body of an embodiment in which the pilot valves of the embodiments of FIGS. 1 and 2 are positioned in a straight line according to some implementations.
[0007] Cross-sectional view of an embodiment of a pilot valve and a pilot body 300 in an open state for fluid to flow according to some implementations.
[0008] This is a cross-sectional view of an embodiment of a hydraulic control valve according to some implementation configurations.
[0009] This is a damper embodiment that includes a pilot valve in some implementation configurations.
[0010] This shows the valve surface configuration of an embodiment of a pilot valve in a certain implementation configuration.
[0011] This is the valve surface configuration of another embodiment of a pilot valve in a particular implementation configuration.
[0012] This is the valve surface configuration of another embodiment of a pilot valve in a particular implementation configuration.
[0013] This is a representative comparative plot of examples showing the predicted reaction forces for different valve surface configurations for various pilot body pressures, depending on some implementation configurations.
[0014] This is another embodiment of the valve surface and its associated pilot valve configuration in a particular implementation.
[0015] Some implementations of the present invention relate to the technology and configuration of pilot valves for hydraulic systems that can be applied in a variety of ways, and may include addressing challenges in vehicle suspension systems such as semi-active hydraulic dampers. Some embodiments of the pilot valve of the present invention allow for precise and immediate adjustment of damping force, thereby enhancing the ride comfort and handling of the vehicle by enabling the vehicle suspension system to adapt to changing road conditions and driving styles. For example, improved responsiveness of the pilot valve of the present invention can result in better stability, traction, and handling, thereby enhancing vehicle performance, while also providing a more cost-effective solution compared to more complex technologies such as fully active dampers and magnetic fluid shock absorbers.
[0016] The embodiments of dampers equipped with pilot valves disclosed herein offer improved damping characteristics and precision, enabling automatic, immediate, and precise adjustment of suspension forces to provide better ride comfort and handling. Furthermore, embodiments of the pilot valves of the present invention improve the response time, allowing the suspension system to quickly adapt to constantly changing road conditions and ensuring optimal vehicle stability and control. Moreover, the pilot valves of the present invention provide a cost-effective solution compared to more complex suspension technologies, with many of the benefits of these more complex technologies being achieved with a simpler solution and lower cost. In addition, embodiments of the present invention may reduce the need for maintenance, extend the lifespan of the suspension system, and increase its durability and reliability.
[0017] Embodiments of the pilot valve of the present invention, such as those used in semi-active hydraulic dampers, offer a balance between performance, simplification, and cost-effectiveness. Furthermore, the pilot valve of the present invention enhances existing hydraulic systems by significantly improving responsiveness and controllability without the high complexity and cost of alternatives such as active damper control or magnetic fluid damper control. As consumer demand for vehicles that offer both comfort and superior driving dynamics grows, the technology described herein enables better suspension control and optimizes vehicle safety and stability. Moreover, as fuel efficiency, sustainability, and regulatory compliance become increasingly important, embodiments of the present invention enable manufacturers to provide more efficient, responsive, and durable suspension systems.
[0018] In some implementations, the damping performance of a damper can be improved, at least partially, by reducing the force acting on the valve surface of the pilot valve of the damper's hydraulic control valve. This can be achieved, in one embodiment, by optimizing the flow direction and the shape of the valve surface of the pilot valve. In embodiments of the present invention, the fluid force on the valve surface of the pilot valve can be significantly reduced. As a result, the damping characteristics of the associated damper employing the pilot valve of the present invention are improved. For example, by changing the flow direction, the damping function of the damper can be significantly enhanced. Thus, the improvement in damping characteristics may be at least partially attributable to a reduction in the force acting on the valve surface of the pilot valve. This reduction in force may be at least partially attributable to the novel valve surface shapes described herein that reduce the fluid force on the valve surface by changing the direction of fluid flow. Thus, embodiments of the present invention include the design of a pilot valve that greatly enhances the damping characteristics, precision, and performance of vehicle suspension systems, specifically semi-active hydraulic dampers in vehicle suspension systems.
[0019] Some embodiments of the present invention relate to semi-active hydraulic dampers that include a pilot valve according to an implementation of the present invention. Semi-active hydraulic dampers use electromagnetic force to provide adjustable and precise damping control. With the increasing demand for smart and connected vehicles, the adoption of electromagnetic dampers, particularly high-performance, function-oriented electromagnetic dampers, is on the rise. In relation to semi-active suspension systems, the pilot valve of the present invention regulates the fluid flow within the damper, thereby adjusting the damping force and improving vehicle performance. The pilot valve of the present invention can meet the increasing performance requirements of modern vehicles by regulating the fluid flow within the damper system so that the suspension system can respond more quickly and accurately and exert greater force.
[0020] For ease of understanding, some implementation examples will be described in relation to pilot valves of hydraulic dampers for vehicle suspension systems. However, the implementation embodiments of the present invention are not limited to the specific embodiments described, and as will be apparent to those skilled in the art based on the disclosures herein, the scope extends to other types of dampers, other types of pilot valve control systems, and other types of hydraulic devices employing pilot valves, poppet valves, etc.
[0021] Figure 1 is a perspective view of a pilot valve 100 according to one embodiment, showing a partial implementation. In this embodiment, the pilot valve 100 includes a valve body 102 which is at least partially cylindrical. The valve body 102 includes a circular flange 104 extending radially outward from the valve body 102. A valve surface 108 is located at the first end 106 of the valve body 102. The circular flange 104 is located near the second end 110 of the valve body 102. The valve surface 108 includes an inner surface 112 and an outer surface 114. The inner surface 112 of the valve surface 108 has the shape of a first truncated cone 113 that converges toward the valve body 102 and the second end 110. The outer surface 114 of the valve surface 108 has the shape of a second truncated cone 115 that is concentric with the first truncated cone 113 that forms the inner surface 112. The second truncated cone 115 forming the outer surface 114 converges in the opposite direction to the first truncated cone 113 of the inner surface 112, and converges in a direction away from the valve body 102, the first end 106, and the second end 110. A flat circular valve seating surface 116 is formed at the apex 117 where the inner surface 112 and the outer surface 114 contact each other. The inner surface 112 extends from the seating surface 116 to an opening 118 that opens into the inner bore 120 of the cylindrical valve body 102, in the direction of the valve body 102 and the second end 110.
[0022] The flange 104 includes an annular lip 122 on the side facing the valve surface 108. The thickness of the flange 104 is thinner between the annular lip 122 and the fillet 124 formed at the contact point between the flange 104 and the cylindrical valve body 102. The pilot valve 100 may be made of metal, polymer, or other suitable material by, for example, machining, casting, molding, forging, or a combination thereof. The material used may be selected to some extent according to the application. Examples of suitable materials include bronze, Monel, Inconel, polymers, monomers, stainless steel, and chromium / molybdenum alloys. The pilot valve 100 of the present invention is not limited to any particular material or manufacturing method.
[0023] Figure 2 is a cross-sectional view of a pilot valve 100 according to one of the implementation configurations. In this embodiment, the first angle 202 of the inner surface 112 with respect to line 204 is greater than the second angle 206 of the outer surface 114 with respect to line 208. For example, line 204 may be parallel to the central axis 210 of the pilot valve 100. Line 208 may extend from the periphery of the cylindrical valve body 102 in a direction parallel to the central axis 210 of the pilot valve 100. Furthermore, the pilot valve 100 may be generally radially symmetrical with respect to the central axis 210 when viewed from the end 106 or 110 of the pilot valve 100. In some embodiments, the first angle 202 may be 30 to 80 degrees and the second angle 206 may be 0 to 45 degrees, but the first angle 202 is maintained to be greater than the second angle 206 in order to respond appropriately to hydraulic force. Furthermore, in some particularly beneficial embodiments where the reaction force can be significantly reduced, the first angle 202 may be 45 to 65 degrees, and the second angle 206 may be 20 to 40 degrees.
[0024] The configuration of the valve surface 108, in which the first angle 202 of the inner surface 112 is greater than the second angle 206 of the outer surface 114, is useful for reducing the fluid force in a hydraulic system employing a pilot valve 100. For example, the configuration of the valve surface 108 may be useful for optimizing fluid flow. In one embodiment, when the pilot valve 100 is used as a hydraulic control valve for a damper in a vehicle suspension system, the configuration of the valve surface 108 allows the pilot valve to move to the open (retracted, i.e., unseaten) position with less fluid pressure compared to conventional pilot valve designs. Thus, the configuration of the valve surface 108 contributes to further efficiency in damping control and further improvement of suspension function.
[0025] Furthermore, in some applications to dampers, the valve surface 108 of the pilot valve 100 may be positioned opposite the fluid inlet at the end of a plunger (not shown in Figure 2), such as a solenoid-controlled plunger, as will be described later. For example, the valve surface 108 is configured such that the first angle 202 of the inner surface 112 is greater than the second angle 206 of the outer surface 114, effectively guiding the flow of the working fluid through a hydraulic system that incorporates a hydraulic control valve including the pilot valve 100 and a solenoid. This improvement in fluid flow enhances the accuracy and responsiveness of the hydraulic control valve of the damper. As a result, embodiments of the present invention address the challenges of conventional pilot valve technology by introducing pilot valve design features that enhance fluid flow control, enabling more precise adjustment of the damper's working fluid. Such improvements directly contribute to more precise adjustment of damping force characteristics, allowing, for example, a semi-active hydraulic damper to respond more effectively to dynamic changes in driving conditions and road surface.
[0026] Furthermore, as will be explained in some embodiments described later, the inner bore 120 of the pilot valve body 102 may include an opening 212 at the second end 110 of the valve body 102. For example, to facilitate the insertion of the solenoid plunger, the opening 212 at the second end 110 may be conical in shape, or it may taper or widen towards the second end 110 (not shown in Figure 2).
[0027] Furthermore, the valve seating surface 116 may have an inner diameter D1 and an outer diameter D2. The difference between diameters D1 and D2 is determined to some extent by the relationship between the first angle 202 of the inner surface 112 and the second angle 206 of the outer surface 114, and also to some extent by the diameter D3 of the opening 118. As will be described later, the diameter D3 may be maintained so that a stationary fluid can flow in under pressure. However, as will be described later, if the diameter D3 is kept constant in embodiments in which various first angles 202 are implemented with respect to the inner surface 112, the thickness T1 of the opening 118 between the valve surface 110 and the inner bore 120 of the valve body may change. The size of D1 may also be determined to some extent based on the diameter of the opening of the valve seat (described later in relation to Figure 3) which forms a seal together with the valve seating surface 116. For example, reducing the diameter D1 of the valve seating surface 116 relative to the size of the valve seat opening helps to improve the responsiveness of the pilot valve 100, and consequently, the responsiveness of the damper or other device on which the pilot valve 100 is installed can also be improved.
[0028] Figure 3 is a cross-sectional view of a pilot body 300 in one embodiment in which the pilot valves 100 in the embodiments of Figures 1 and 2 are aligned in a straight line, according to some implementation configurations. In this embodiment, the pilot valve seating surface 116 of the pilot valve 100 is shown in contact with the circular valve seat 302 of the pilot body 300. The pilot valve 100 is aligned in a straight line with the fluid flow path 304 of the pilot body 300, and the central axis 210 of the pilot valve 100 is aligned in a straight line with the central axis 306 of the pilot body 300. The flow path 304 includes a flow opening 307. The flow opening 307 has a diameter D4 that opens in the center of the valve seat 302 such that the pilot valve seating surface 116 forms a circular seal together with the valve seat 302 around the flow opening 307. As will be further described later, the valve seating surface 116 may have an inner diameter D1 such that, as described above, the size of the diameter D1 is determined relative to the flow opening 307, except to take into account the tolerances in the manufacturing, assembly, and operation of the pilot valve 100 relative to the pilot body. As previously described, the inner diameter D1 of the pilot valve seating surface 116 may be determined to some extent based on the relative angles of the first angle 206 and the second angle 208, which can also affect the size of the total contact area of the valve seating surface 116 with respect to the valve seat 302. For example, by reducing the diameter D1 of the valve seating surface 116 relative to the diameter D4 of the flow opening 307 of the valve seat 302, the responsiveness of the pilot valve 100 can be improved, and consequently, the responsiveness of the damper or other device on which the pilot valve 100 and the pilot body 300 are installed can also be improved.
[0029] The pilot body 300 further includes an annular fluid passage 308 around the pilot valve 100 so that when the pilot valve seating surface 116 is separated from the circular valve seat 302 of the pilot body 300, fluid flows through the fluid passage 300 of the pilot body and into the annular fluid passage 308. The configuration of the valve surface 108 of the pilot valve 100 contributes to improving the responsiveness and precision of the pilot valve 100 in order to allow fluid to flow into the annular fluid passage 308.
[0030] For example, a fluid pressure 310 may be applied to the surface 108 of the pilot valve via the fluid passage 304 and the fluid opening 307. The fluid pressure 310 can be counteracted by a solenoid force 312 that presses the pilot valve seating surface 116 of the pilot valve 100 against the valve seat 302 of the pilot body 300. As will be described later with respect to Figure 4, when the fluid pressure 310 exceeds the solenoid force 312, the pilot valve retracts from the valve seat 302, allowing fluid to flow into the annular fluid passage 308.
[0031] Figure 4 is a cross-sectional view 400 of an embodiment of a pilot valve 100 and pilot body 300 in an open state to allow fluid to flow, according to one of the implementation configurations. In this embodiment, as shown in Figure 3 above, the pilot valve seating surface 116 of the pilot valve 100 is in contact with the valve seat 302 of the pilot body 300 in the first state to prevent the fluid flow from flowing from the fluid passage 304 into the annular fluid passage 308. For example, a solenoid force 312 can press the pilot valve 100 against the valve seat 302 of the pilot body 300, forming a seal between the valve seating surface 116 and the valve seat 302. On the other hand, in the embodiment of Figure 4, as indicated by the arrow 402, the fluid pressure 310 in the fluid passage 304 can rise to such an extent that it can push the valve surface 108 of the pilot valve 100 and separate the pilot valve 100 from the valve seat 302. When the valve seating surface 116 and the pilot valve 100 separate from the valve seat 302, the fluid flows out of the fluid passage 304, flows in the direction of fluid flow indicated by arrow 404, passes through the valve seating surface 116, and flows into the annular fluid passage 308.
[0032] As an embodiment, as will be further described later, the movement of a damper piston (not shown in Figure 4) can increase the fluid pressure 310 acting in the direction of the pilot valve 100. This increased pressure can push the pilot valve 100 in the direction of arrow 402, which moves it away from the valve seat 302, against the solenoid force 312. As a result, the fluid flows through the annular passage 308 in the direction of the fluid flow 404. As previously described, the configuration of the valve surface 108 in the embodiment of the present invention can improve the responsiveness of the pilot valve by reducing the amount of fluid pressure 310 required to move the pilot valve 100 away from the valve seat 302.
[0033] Furthermore, as explained with respect to Figure 2, for example, embodiments of the present invention optimally reduce fluid forces based on a first angle 202 of the inner surface 112 of the valve surface that is greater than a second angle 206 of the outer surface 114 (see, for example, Figures 1 and 2). Thus, embodiments of the present invention may include a specific design parameter in which the first angle 202 is always greater than the second angle 206. This has the effect of reducing fluid forces inside a hydraulic control valve (hydraulic control valve) including a pilot valve 100 and a pilot body 300. When the valve surface configuration described herein is adopted in a semi-active hydraulic damper, as further described later, the valve surface configuration can improve fluid flow control and allow for more precise control of damping force. As a result, the suspension function becomes smoother and vehicle operation is improved.
[0034] Embodiments of the present invention include the orientation of a valve surface positioned opposite the flow opening 307 of the flow path 304. The valve surface configuration of the present invention allows for optimal guidance of the fluid flow. For example, the valve surface 108 of the present invention can enhance the responsiveness and efficiency of the damping system by guiding the fluid flow in a manner that maximizes function and minimizes resistance. This is useful in addressing the specific limitations of existing hydraulic valve devices as described above. In one embodiment, when the pilot valve configuration of the present invention is provided in the hydraulic control valve of a semi-active hydraulic damper, it can significantly improve the damping characteristics for creating a more efficient, responsive, cost-effective, and functionally improved semi-active hydraulic damper.
[0035] Figure 5 is a cross-sectional view of a hydraulic control valve 500 in an embodiment of a particular implementation. In this embodiment, the pilot body 300 described in relation to Figures 3 and 4 is located within the outer housing 502 of the hydraulic control valve. The outer housing 502 may be generally cylindrical and may receive a portion of the inner housing 504. The inner housing 504 may also be generally cylindrical and is partially inserted into the outer housing 502. The inner housing 504 houses a solenoid 506 including a plunger 508. The plunger end 510 of the plunger 508 may be located within the bore 120 of the pilot valve 100. The solenoid 506 may be driven to apply a solenoid force in the opposite direction to the fluid pressure 310, as described in relation to Figures 3 and 4, so that the pilot valve 100 is pressed toward the valve seat 302 of the pilot body 300, as described and illustrated in relation to Figures 3 and 4.
[0036] In one application to a damper, the valve surface 108 of the pilot valve 100 may be positioned opposite the solenoid and solenoid plunger that apply the solenoid force 312, as shown in the figure, and may face the fluid pressure 310 that may be flowing under pressure from the damper, as described in relation to Figure 4. The configuration of the valve surface 602 is useful in reducing the fluid force in the hydraulic system in which the pilot valve 100 is employed, in order to effectively guide the flow of the working fluid in the hydraulic system that includes the hydraulic control valve 500 including the pilot valve 100. This improvement in fluid flow enhances the accuracy and responsiveness of the damper or other hydraulic system in which the hydraulic control valve 500 having the pilot valve 100 of the present invention is employed.
[0037] Figure 6 shows a damper 600 in an embodiment that includes a pilot valve 100 in some implementation configurations. In the illustrated embodiment, the damper 600 is configured as a semi-active hydraulic damper, but other implementation configurations of the present invention are not limited to any particular damper configuration. In this embodiment, the damper 600 includes an inner tube 602 that can function as a pressure tube and an outer tube 604 arranged concentrically around the inner tube 602. An annular space 606 that functions as a gas chamber in some embodiments may be located between at least a portion of the inner tube 602 and the outer tube 604. An intermediate tube 608 may also be located in the annular space 606, concentrically surrounding at least a portion of the inner tube 602.
[0038] A hydraulic valve, such as the hydraulic control valve 500, is mounted on the outside of the outer tube 604. The hydraulic valve includes a pilot valve 100 and a pilot body 300. Another annular space 610 between the intermediate tube 608 and the inner tube 602 is connected to the interior 612 of the inner tube 602 via one or more passages. This allows fluid to flow between the interior 612 of the inner tube 602 and the annular space 610, and thereby to the hydraulic control valve 500, which is in fluid communication with the annular spaces 606 and 612. The hydraulic control valve 500 may be configured to control, at least to some extent, the flow of working fluid within the damper 600.
[0039] Rod guides 616 are positioned at the first end 617 of the inner tube 602 and the outer tube 604. A piston rod 618 is inserted through the bore of the rod guide 616 and can reciprocate within the bore of the rod guide 616. A piston 620 is positioned at one end of the piston rod 618. The piston 620 is fitted into the bore of the inner tube 602 so that the piston 620 and the piston rod 618 can reciprocate within the interior 612 of the inner tube. For example, the piston 620 and the piston rod 618 reciprocate within the inner tube 602 in response to an external force applied to the piston rod 618 and a damper mounting base 624 positioned at the second end 625 of the damper 600. As is known in the art, the interior 612 of the inner tube 602 may include a compression chamber 626 that the piston 620 approaches during its retraction stroke and an extension chamber 630 that the piston 620 approaches during its extension stroke. The base valve 634 is located at the second end 625 of the damper 600 and controls the fluid flow during fluid compression and replenishment. Arrow 632 indicates the fluid flow through the damper 600 and the hydraulic control valve 500 during the compression stroke. Arrow 628 indicates the fluid flow through the piston 620 during the extension stroke. Arrow 636 indicates the fluid flow into the compression chamber for fluid replenishment during the extension stroke.
[0040] As shown in Figure 6, the inclusion of a pilot control valve 100 in the damper 600 improves the hydraulic function of the damper 600. For example, in a semi-active hydraulic damper, fluid is metered and supplied to the intermediate pipe 610 via the extension chamber 630, regardless of the direction of suspension movement, and then metered and supplied to a reserve chamber such as an annular space 606 via the pilot control valve 100. During the compression stroke in the "soft" mode of the suspension, the fluid flows from the compression chamber 626 to the extension chamber 630, into the intermediate pipe 610, and then through the pilot control valve 100 into the reserve chamber. When the stroke reverses from compression to extension, the compression chamber 630 is replenished via the base valve 634, as indicated by arrow 636. Thus, the pilot valve 100 in the damper 600 of this embodiment can function as a two-stage hydraulic control valve. To facilitate the implementation of the vehicle's semi-active suspension function, a semi-active hydraulic damper, including the pilot valve 100 described herein, may be installed on each wheel of the vehicle (for example, one damper per wheel).
[0041] In some embodiments, the hydraulic control valve 500 may be a fast-responding electro-hydraulic valve that allows for immediate adjustment of the damping force. The damper 600, including the hydraulic control valve 500, includes a pilot valve 100 as described with respect to Figures 1 to 5. This reduces the hydraulic reaction force without changing the solenoid characteristics. The size and shape of the pilot valve may be optimized according to the disclosures herein in order to achieve smooth fluid flow, minimize turbulence, and ensure stable flow characteristics. Techniques for obtaining desirable force characteristics can be achieved, for example, by adjusting the area of the pilot valve 100, i.e., the valve surface 108, that comes into contact with the working fluid, by implementing the valve surface configuration described above with respect to Figures 1 to 2 and further described with respect to Figures 7 to 11.
[0042] Figures 7 to 9 are cross-sectional views of a pilot valve according to three embodiments, having valve face configurations of three different embodiments according to some implementation manners. The predicted reduction in reaction force is determined for each embodiment using a computer model simulation. The results of the computer simulation will be described in relation to Figure 10.
[0043] The process of opening (lifting) the pilot valve 100 involves an alternating change in the force acting on the valve face, including the transition between the equilibrium state and the non-equilibrium state. The geometric characteristics of the valve face 108 of the pilot valve 100 in the damper 600 may affect the resistance provided by the damper 600. Therefore, the hydraulic pressure (oil pressure) acting on the pilot valve 100 can significantly affect the overall performance of the damper 600. To quantify the reaction force of the pilot valve 100, various valve displacements and operating hydraulic pressures were simulated using comprehensive three-dimensional (3D) computational fluid dynamics. To confirm the validity of the results of the computational model, a pilot valve 100 of one embodiment was tested in a test device, and the hydraulic (oil pressure) damping force characteristics were determined with various input values. A representative example of the simulation model will be described later in relation to Figure 10.
[0044] Figure 7 is a valve face configuration of an embodiment in the pilot valve 100-1 according to some implementation manners. In the embodiment of Figure 7, the pilot valve 100-1 includes a valve face 108 having a configuration for reducing hydraulic (oil pressure) reaction force. In this embodiment, as described with respect to Figures 1 to 2, the inner surface 112 of the valve face 108 has the shape of a first frustum of a cone that converges toward the valve body 102 and the second end 110. The outer surface 114 of the valve face 108 has the shape of a second frustum of a cone that is concentric with the first frustum of a cone forming the inner surface 112. The second frustum of a cone forming the outer surface 114 converges in the opposite direction to the first frustum of a cone of the inner surface 112 and converges in a direction away from the valve body 102, the first end 106, and the second end 110. Further, as described above, the valve face 108 and the pilot valve 100 itself may be generally radially symmetric with respect to the central axis 210 when viewed from the end 106 or 110 of the pilot valve 100.
[0045] In this embodiment, the first angle 202 of the inner surface with respect to the line 204 (parallel to the central axis 210) is set to 60 degrees, and the second angle 206 of the outer surface 114 with respect to the line 208 extending parallel to the central axis 210 of the pilot valve 100 from the periphery of the pilot valve body 102 is set to 30 degrees.
[0046] Also, in this embodiment, as described above, the valve seating surface 116 may have an inner diameter D1 and an outer diameter D2 that are determined according to the valve seat and the flow opening of the pilot body 300. The diameter D1 may be determined according to the diameter D4 of the flow opening 307 of the pilot body as described above so as to be large enough to reliably form a seal between the valve seating surface 116 and the valve seat 302. For example, if the diameter of the valve seating surface 116 is restricted according to the flow opening 307 of the valve seat 302, the responsiveness of the pilot valve 100 can be improved, and thus the responsiveness of the damper 600 in which the pilot valve 100 is installed can also be improved.
[0047] FIG. 8 shows the valve surface configuration of another embodiment in the pilot valve 100-2 according to some implementation modes. The configuration of the valve surface 108 in FIG. 8 is the same as the configuration described with respect to FIG. 7, except that the first angle 202 is 55 degrees and the second angle 206 is maintained at 30 degrees. In order to match the more acute first angle, while keeping the diameter D3 of the opening 118 the same, the thickness T1 of the opening is made thinner. For example, assume that in the embodiment of FIG. 7, the thickness T1 is 0.47 mm, and in the embodiment of FIG. 8, the thickness T1 is 0.4 mm. Further, in this embodiment, the diameter D1 is also smaller, for example, assume that in FIG. 8 it is 3.5 mm and in FIG. 7 it is 3.6 mm.
[0048] Figure 9 shows the valve surface configuration of another embodiment of the pilot valve 100-3 according to some implementation configurations. The configuration of the valve surface 108 in Figure 8 is the same as the configuration described with respect to Figures 7 and 8, except that the first angle 202 is maintained at 52 degrees and the second angle 206 is maintained at 30 degrees. To match the sharper first angle, the diameter D3 of the opening 118 is kept the same, while the thickness T1 of the opening is made thinner. For example, assume that the thickness T1 is 0.3 mm in the embodiment of Figure 9, 0.47 mm in the embodiment of Figure 7, and 0.4 mm in the embodiment of Figure 8. Furthermore, in this embodiment, assume that the diameter D1 is also smaller, for example, 3.4 mm. On the other hand, for example, the diameter D1 in Figure 8 may be 3.5 mm, and the diameter D1 in Figure 7 may be 3.6 mm. Furthermore, based on the above dimensions according to the embodiment, the area of the inner surface 112 is 9.43 mm in Figure 7. 2 In Figure 8, the measurement is 9.29 mm. 2 In Figure 9, the measurement is 8.97 mm. 2 Let's assume that.
[0049] Figure 10 is a representative comparative plot 1000 of an embodiment showing the expected reaction force for different valve surface configurations for various pilot body pressures, depending on some implementations. For example, a semi-active hydraulic damper, such as the damper 600 described with respect to Figure 6, can optimize vehicle control to improve safety, comfort, and dynamics without compromising ride comfort or addressing vehicle characteristics. A semi-active hydraulic damper solves a specific problem by bridging the gap between vehicle ride comfort and driving dynamics. With conventional dampers, these two characteristics require diametrically opposed adjustment methods. Either one is easily achieved, but both are difficult to achieve simultaneously. In principle, a semi-active damper uses one or two solenoids to receive electrical signals from the vehicle's electronic chassis controller and mechanically alter the hydraulic flow path within the damper. This happens in a mere instant to mitigate changes in the vehicle's chassis due to road surface or steering input. For example, it's not uncommon for the damping force to increase fourfold between the "soft" and "hard" settings of a damper.
[0050] In a semi-active hydraulic damper, it is desirable that the physical changes in the hydraulic circuit are small, while simultaneously causing a large change in the hydraulic resistance (measured in terms of "damping force"). The pilot-controlled valve circuit (PVC) encompassing the pilot valve 100 of the present invention may include a pilot chamber and a main chamber (not shown in Figure 6). The pilot chamber increases the pressure while providing a back pressure proportional to the valve adjustment of the main chamber. As more fluid flows through the main chamber, the increased back pressure from the pilot chamber significantly affects the fluid. This can increase the overall resistance of the PVC circuit and, consequently, the output of the damping force of the semi-active hydraulic damper. By placing a solenoid 506 in the pilot chamber, large control becomes possible with minimal mechanical movement. In this case, the solenoid 506 is configured to control the pressure in the pilot chamber by controlling the resistance to the outlet flow path. Specifically, the solenoid provides a holding force from the pilot chamber to the pilot valve 100 that controls the outlet area. This holding force is designed to be suppressed by hydraulic pressure. Changing the holding force via the solenoid 506 alters not only the amount of hydraulic pressure required to open the pilot valve 100, but also the degree to which the pilot valve 100 opens. The holding force is controlled by changing the amperage (current value) commanded by the vehicle's electronic chassis controller. While some applications differ, increasing the amperage typically leads to an increase in holding force, and consequently, an increase in the damper's damping force. Control of the outlet area by the pilot chamber significantly affects the damper's damping force output.
[0051] In the embodiment of Figure 10, plot 1000 includes a comparison of the curves of the reaction forces acting on the pilot valve, determined from the results of simulation models for the pilot valve opening degree under various pilot body pressures, for a conventional pilot valve and three embodiment configurations of pilot valves 100-1, 100-2, and 100-3 described in Figures 7-9. The caption 1002 contains symbols representing the curves for the valve surface configurations of the different embodiments. As shown, in plots 1004 to 1010 of 1000, the predicted reaction forces for the conventional pilot valve configuration are greater than the predicted reaction forces for embodiment configurations 100-1 to 100-3. Furthermore, as shown in 1003, the predicted reaction force for configuration 100-3 in Figure 9 is predicted to be slightly smaller than the predicted reaction forces for configuration 100-1 in Figure 7 and configuration 100-2 in Figure 8.
[0052] Figure 11 shows another embodiment configuration of the valve surface 108 and its associated pilot valve 100-4 according to some implementation configurations. In this embodiment, rather than reducing the thickness T1 of the opening 118 for a sharper first angle 102, a washer-shaped, circular, flat region 1102 having a width W1 may be included around the outer edge of the opening 118 to maintain the opening at the same diameter D3, regardless of the angle of the first angle 102. Furthermore, for convenience of explanation, several embodiment configurations of the valve surface 108 are described herein, but the implementation configurations are not limited to the disclosed embodiments and may be extended to a variety of other configurations as will be apparent to those skilled in the art who are interested in the contents of this disclosure.
[0053] The pilot valve configuration disclosed herein significantly enhances the damping performance of a damper by enabling more precise control of fluid dynamics within the suspension system. Furthermore, it can significantly increase the damping output without substantially altering the overall design of conventional semi-active hydraulic dampers. As a result, the solution disclosed herein is cost-effective and easy to implement, as it significantly enhances the performance of semi-active hydraulic dampers without extensive modifications.
[0054] The pilot valve 100 of the present invention may be used in various types of hydraulic systems. In the case of semi-active hydraulic dampers, the pilot valve 100 of the present invention may be suitable for electric vehicles (EVs), autonomous vehicles, luxury vehicles, and performance vehicles where precise control of suspension behavior is highly valued. For example, in a semi-active hydraulic damper system, the pilot valve 100 enhances the damping characteristics, ensuring optimal performance across various driving conditions. As a result of the improved efficiency of the pilot valve 100, the damping characteristics are improved by the precise and efficient regulation of the hydraulic fluid flow. To reduce the pressure level on the pilot valve 100, the pilot valve 100 is configured with a tapered valve surface having a first angle greater than a second angle. Thus, embodiments of the present invention provide a widely applicable and cost-effective solution for enhancing the suspension systems of a wide range of vehicles and ensuring better ride comfort, stability, and efficiency. Embodiments of the present invention address the challenges of conventional pilot valve technology by introducing features of a pilot valve design that enhance fluid flow control, enabling more precise adjustment of the working fluid in damper systems and the like. This improvement directly contributes to more precise adjustment of damping force characteristics, allowing semi-active dampers to respond more effectively to dynamic changes in driving conditions and road surfaces, for example.
[0055] This disclosure provides various implementation configurations as described and illustrated in the figures. However, as is well known to those skilled in the art, the scope of this disclosure is not limited to the implementation configurations described and illustrated herein, but extends to other implementation configurations. Furthermore, while specific embodiments are described or illustrated herein as providing certain effects, some claimed embodiments may not provide any of these effects, or may provide some or all of them.
[0056] While the subject matter is described using language specific to structural features and / or methodological actions, it should be understood that the subject matter described in the dependent claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions are disclosed as exemplary forms of implementing the claims.
Claims
1. A valve device comprising a valve including a valve body having a central axis and a valve surface disposed at a first end of the valve body, wherein the valve surface includes an outer surface and an inner surface that contact each other at the apex where a circular valve seat surface is disposed, the inner surface is formed as a first truncated cone cone converging in a first direction toward the valve body, the outer surface is formed as a second truncated cone converging in a second direction away from the valve body, the inner surface has a first angle with respect to the central axis, the outer surface has a second angle with respect to a line extending from the periphery of the valve body that is parallel to the central axis, the first angle of the inner surface is greater than the second angle of the outer surface, and further comprising a pilot body having a fluid passage opening, the valve seat surrounding the fluid passage opening, A valve device wherein the circular valve seating surface of the valve is configured to contact the valve seat in a first position to form a seal, thereby preventing fluid from passing between the circular valve seating surface and the valve seat, and the valve is movable from the first position to a second position so that fluid can pass between the circular valve seating surface and the valve seat.
2. A valve device according to claim 1, characterized in that the first angle is 45 to 65 degrees and the second angle is 20 to 40 degrees.
3. A valve device according to claim 1, characterized in that the first angle is 30 to 80 degrees, the second angle is 0 to 45 degrees, and the first angle is greater than the second angle.
4. A valve device according to claim 1, wherein the valve body is cylindrical, and the inner surface includes an opening in the center that opens into the bore of the cylindrical valve body.
5. A valve device according to claim 1, characterized in that the diameter of the circular valve seating surface is controlled relative to the diameter of the fluid flow opening in order to minimize the amount of fluid pressure required to move the valve to the second position.
6. A valve device according to claim 1, wherein the valve body includes an opening at its second end, and the inner bore is configured to receive the plunger end of the plunger, and the plunger is configured to press the circular valve seating surface of the valve against the valve seat at a first position.
7. A valve device according to claim 6, characterized in that the valve and pilot body are included in a hydraulic control valve which includes a solenoid driven by the plunger to press the circular valve seating surface against the valve seat.
8. A valve device according to claim 7, wherein the hydraulic control valve is in fluid communication with a damper, and the configuration of the valve surface reduces the amount of fluid pressure required to separate the circular valve seating surface from the valve seat, thereby enhancing the responsiveness of the damper.
9. A valve device according to claim 1, further comprising a washer-shaped flat region disposed between the inner surface and the periphery or outer edge of an opening concentric with the inner surface.
10. A damper comprising an inner tube having a piston and a piston rod, wherein the piston and the piston rod are configured to reciprocate within the inner tube, an outer tube disposed around the inner tube, a hydraulic control valve fluidly communicating with the inside of the outer tube to receive fluid from the damper and return fluid to the damper, and a valve disposed in the hydraulic control valve, wherein the valve includes a valve surface having an outer surface and an inner surface that contact each other at the apex where a circular valve seat surface is located, the inner surface having the shape of a first truncated cone cone converging in a first direction toward the valve body, the outer surface having the shape of a second truncated cone converging in a second direction away from the valve body, the inner surface having a first angle with respect to the central axis, the outer surface having a second angle with respect to a line extending from the periphery of the valve body that is parallel to the central axis, the first angle of the inner surface being greater than the second angle of the outer surface. The damper is characterized by comprising a pilot body positioned on the hydraulic control valve, the pilot body having a fluid passage opening, the fluid passage opening being surrounded by a valve seat, the circular valve seating surface being configured to contact the valve seat at a first position to form a seal that prevents fluid from passing between the circular valve seating surface and the valve seat, and the valve being movable from the first position to a second position so that fluid can pass between the circular valve seating surface and the valve seat.
11. A damper according to claim 10, characterized in that the first angle is 45 to 65 degrees and the second angle is 20 to 40 degrees.
12. A damper according to claim 10, characterized in that the diameter of the circular valve seating surface is controlled relative to the diameter of the fluid passage opening in order to minimize the amount of fluid pressure required to move the valve to the second position.
13. A damper according to claim 10, wherein the hydraulic control valve further comprises a solenoid having a plunger, the plunger end of the plunger is positioned in the inner bore of the valve body, and the solenoid is configured to be driven by the plunger to press the circular valve seating surface against the valve seat.
14. A damper according to claim 10, further comprising an intermediate pipe disposed around at least a portion of the inner pipe in the annular space between the inner pipe and the outer pipe, wherein the intermediate pipe is configured to receive fluid and send the fluid to the hydraulic control valve.
15. A damper according to claim 10, characterized in that the damper is a semi-active hydraulic damper.
16. A valve device for forming a seal, wherein a valve seat is positioned around the outer edge of a fluid passage, the valve device comprising a valve including a valve body having a central axis and a valve surface positioned at a first end of the valve body, wherein the valve surface includes an outer surface and an inner surface with a circular valve seat surface positioned between them, the inner surface having the shape of a first truncated cone cone converging in a first direction toward the valve body, the outer surface having the shape of a second truncated cone converging in a second direction away from the valve body, the inner surface having a first angle with respect to the central axis, the outer surface having a second angle with respect to a line extending from outside the valve body and parallel to the central axis, the first angle of the inner surface being greater than the second angle of the outer surface, and the circular valve seat surface being positioned to form the valve seat and the seal.
17. A valve device according to claim 16, characterized in that the first angle is 45 to 65 degrees and the second angle is 20 to 40 degrees.
18. A valve device according to claim 16, wherein the circular valve seating surface of the valve is configured to contact the valve seat at a first position to form the valve seat and the seal, thereby preventing fluid from passing between the circular valve seating surface and the valve seat, and the valve is movable from the first position to a second position so that fluid can pass between the circular valve seating surface and the valve seat.
19. A valve device according to claim 18, wherein the valve body includes an opening at its second end, and the inner bore is configured to receive the plunger end of the plunger, and the plunger is configured to press the circular valve seating surface of the valve against the valve seat at a first position.
20. A valve device according to claim 19, characterized in that the valve is provided in a hydraulic control valve having a solenoid driven by the plunger to press the circular valve seating surface against the valve seat.