Damper assembly and piston for damper assembly

Abstract

The invention provides a damper assembly and a piston used for the damper assembly. The piston includes a pressure sensitive relief valve including at least one working disc and an outer disc disposed radially outward of the at least one working disc. The at least one working disc abuts the outer disc in the radial direction and is deflectable in two opposite directions along the central axis to regulate the flow of the working fluid through the piston during a compression stroke and a rebound stroke.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application Serial No. 63 / 567,670, filed on March 20, 2024, the entire contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] The present disclosure generally relates to a damper assembly and a piston for a damper assembly. Background Art

[0004] Shock absorbers are usually designed to provide the desired level of damping force in the vehicle suspension. In order to ensure appropriate vehicle dynamics, the operation of the shock absorber can be divided into two intervals: low speed and high speed. The division into these two intervals is achieved by adopting an appropriate valve design. At low speeds (and therefore low pressures), the oil in the shock absorber flows through a smaller orifice with a constant cross-section. In the high-speed range (i.e. after exceeding a given pressure level), the preload relief valves (usually shim-valves or blow-off valves) open and the oil flow becomes less restricted. As a result, a larger damping coefficient is obtained in the low-speed range, while a smaller damping coefficient is obtained in the high-speed range.

[0005] A significant disadvantage of most common vehicle damper valves is that the damping characteristics in the low speed range correspond to the simple flow characteristics of the oil through a constant throttle orifice (also called constant bleed). As a result, the damping force is close to zero in the very low speed range and increases slowly and gradually as the speed increases. The flow characteristics in the lowest speed range cannot be adjusted. This limitation has a negative impact on both handling and ride comfort.

[0006] Therefore, more complex damper valve designs may be needed to mitigate or eliminate these negative effects and provide a damper with adjustable characteristics in the low speed range. In addition, there remains a need for improvements in such shock absorber valves to improve reliability, manufacturability and reduce cost. Summary of the invention

[0007] The present disclosure, in its broadest aspect, provides a damper assembly and a piston for a damper assembly.

[0008] One aspect of the present disclosure is to provide a damper assembly, which includes a housing, a piston, a piston rod, a compression valve, a rebound valve and a pressure-sensitive relief valve. The housing defines a fluid chamber extending along a central axis to accommodate a working fluid. The piston is slidably arranged in the fluid chamber, thereby dividing the fluid chamber into a rebound chamber and a compression chamber. The piston rod extends along the central axis and is coupled to the piston to move the piston between a compression stroke and a rebound stroke. The piston defines at least one compression channel, at least one rebound channel and at least one additional channel to allow the working fluid to flow through the piston during the compression stroke and the rebound stroke. The compression valve covers the at least one compression channel to regulate the flow of the working fluid through the piston during the compression stroke. The rebound valve covers the at least one rebound channel to regulate the flow of the working fluid through the piston during the rebound stroke. The pressure-sensitive relief valve covers the at least one additional channel and includes at least one working disk and an outer disk disposed radially outside the at least one working disk. The at least one working disk abuts against the outer disk in a radial direction and can deflect in two opposite directions along the central axis to regulate the flow of the working fluid through the piston during the compression stroke and the rebound stroke.

[0009] In an embodiment of the present disclosure, the at least one compression channel is fluidly connected to the at least one rebound channel through the at least one additional channel; and the at least one working disk cuts off the fluid connection by abutting against the outer disk, and opens the fluid connection by deflecting in either of two opposite directions along the central axis.

[0010] In an embodiment of the present disclosure, the at least one additional channel is radially spaced apart from the at least one compression channel and radially spaced apart from the at least one rebound channel, and the at least one additional channel is axially spaced apart from the rebound valve and axially spaced apart from the compression valve; and the pressure-sensitive relief valve is axially located between the compression valve and the at least one additional channel, and the pressure-sensitive relief valve is axially spaced apart from the compression valve and axially spaced apart from the at least one additional channel.

[0011] In an embodiment of the present disclosure, the piston defines a first groove, the at least one compression channel is in fluid communication with the at least one additional channel through the first groove, and the pressure sensitive relief valve is located in the first groove.

[0012] In an embodiment of the present disclosure, the damper assembly further includes a support disk disposed on a surface of the compression valve facing the pressure sensitive relief valve to support the compression valve and prevent the compression valve from excessively deflecting toward the pressure sensitive relief valve during a rebound stroke.

[0013] In an embodiment of the present disclosure, the rebound valve defines a flow channel, and in a non-deflected state of the rebound valve, the compression chamber communicates with at least one rebound channel through the flow channel.

[0014] In an embodiment of the present disclosure, the flow passage is formed by a plurality of radially outer notches disposed on at least one disk of the rebound valve.

[0015] In an embodiment of the present disclosure, the piston defines a second groove, the at least one rebound channel is in fluid communication with the at least one additional channel through the second groove, and the flow channel is in fluid communication with the at least one additional channel through the second groove.

[0016] In an embodiment of the present disclosure, the at least one working disk includes: a main working disk, which is against the outer disk in the radial direction; at least one compression working disk, which is arranged on the surface of the main working disk facing the compression chamber, and its outer diameter is smaller than the outer diameter of the main working disk; and at least one rebound working disk, which is arranged on the other surface of the main working disk facing the rebound chamber, and its outer diameter is smaller than the outer diameter of the main working disk.

[0017] In an embodiment of the present disclosure, the damper assembly also includes a mounting ring, through which the outer disk is clamped on the piston, and the inner diameter of the mounting ring is larger than the inner diameter of the outer disk; and a gasket, through which at least one working disk is clamped on the piston, and the outer diameter of the gasket is smaller than the outer diameter of the at least one working disk.

[0018] Another aspect of the present disclosure provides a piston for a damper assembly. The piston includes a piston body, a compression valve, a rebound valve, and a pressure-sensitive relief valve. The piston body defines at least one compression channel, at least one rebound channel, and at least one additional channel to allow a working fluid to flow through the piston body during a compression stroke and a rebound stroke. The compression valve covers the at least one compression channel to regulate the flow of the working fluid through the piston body during the compression stroke. The rebound valve covers the at least one rebound channel to regulate the flow of the working fluid through the piston body during the rebound stroke. The pressure-sensitive relief valve covers the at least one additional channel and includes at least one working disk and an outer disk disposed radially outward of the at least one working disk. The at least one working disk abuts against the outer disk in a radial direction and can deflect in two opposite directions along a center axis to regulate the flow of the working fluid through the piston body during the compression stroke and the rebound stroke.

[0019] In an embodiment of the present disclosure, the at least one compression channel is fluidly connected to the at least one rebound channel through the at least one additional channel; and the at least one working disk cuts off the fluid connection by abutting against the outer disk, and opens the fluid connection by deflecting in either of the two opposite axial directions.

[0020] In an embodiment of the present disclosure, the at least one additional channel is radially spaced apart from the at least one compression channel and radially spaced apart from the at least one rebound channel, and the at least one additional channel is axially spaced apart from the rebound valve and axially spaced apart from the compression valve; and the pressure-sensitive relief valve is axially located between the compression valve and the at least one additional channel, and the pressure-sensitive relief valve is axially spaced apart from the compression valve and axially spaced apart from the at least one additional channel.

[0021] In an embodiment of the present disclosure, the piston body defines a first groove, the at least one compression channel is in fluid communication with the at least one additional channel through the first groove, and the pressure sensitive relief valve is located in the first groove.

[0022] In an embodiment of the present disclosure, the piston further includes a support disk disposed on a surface of the compression valve facing the pressure sensitive relief valve to support the compression valve and prevent the compression valve from excessively deflecting toward the pressure sensitive relief valve during a rebound stroke.

[0023] In an embodiment of the present disclosure, the rebound valve defines a flow channel, and in a non-deflected state of the rebound valve, the compression chamber communicates with the at least one rebound channel through the flow channel.

[0024] In one embodiment of the present disclosure, the flow passage is formed by a plurality of radially outer notches disposed on at least one disk of the rebound valve.

[0025] In one embodiment of the present disclosure, the piston body defines a second groove, the at least one rebound channel is in fluid communication with the at least one additional channel through the second groove, and the flow channel is in fluid communication with the at least one additional channel through the second groove.

[0026] In one embodiment of the present disclosure, the at least one working disk includes: a main working disk, which is against the outer disk in the radial direction; at least one compression working disk, which is arranged on the surface of the main working disk facing the rebound valve, and its outer diameter is smaller than the outer diameter of the main working disk; and at least one rebound working disk, which is arranged on the other surface of the main working disk facing the compression valve, and its outer diameter is smaller than the outer diameter of the main working disk.

[0027] In one embodiment of the present disclosure, the piston also includes: a mounting ring, through which the outer disk is clamped on the piston body, and the inner diameter of the mounting ring is larger than the inner diameter of the outer disk; and a gasket, through which the at least one working disk is clamped on the piston body, and the outer diameter of the gasket is smaller than the outer diameter of the at least one working disk.

[0028] The pressure sensitive relief valve of the present disclosure provides an appropriate level of damping starting from a damper velocity close to zero and increases the damping force in a more linear way until the inflection point (the point at which the pressure relief valve opens) is reached. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Other advantages of the present invention will be readily appreciated as they are better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings, in which:

[0030] Figure 1 showing a cross-sectional view of a damper assembly constructed in accordance with one embodiment of the present disclosure;

[0031] Figure 2 A cross-sectional view showing a piston and piston rod comprising a pressure sensitive relief valve assembly constructed in accordance with one embodiment of the present disclosure;

[0032] Figure 3 Show Figure 2 Exploded view of the piston;

[0033] Figure 4 A graph showing force versus velocity, wherein the curves show the damping characteristics of a conventional valve and a pressure sensitive relief valve according to one aspect of the present disclosure and show the adjustment range of the pressure sensitive relief valve of the present disclosure;

[0034] Figure 5 A cross-sectional view of a piston including a pressure sensitive relief valve of the present disclosure is shown, and the oil flow path through the piston is shown during the rebound stroke and the compression stroke and at low damper speeds;

[0035] Figure 6 A cross-sectional view showing a piston including a pressure sensitive relief valve of the present disclosure and showing the oil flow path through the piston during the rebound stroke and the compression stroke and at high damper speeds; and

[0036] Figure 7 Another cross-sectional view of a piston is shown according to one embodiment of the present disclosure. DETAILED DESCRIPTION

[0037] Referring to the drawings, wherein like reference numerals designate corresponding parts throughout the several views, Figures 1 to 7 A damper assembly 20 having a pressure sensitive relief valve 51 constructed in accordance with one embodiment of the present disclosure is generally illustrated.

[0038] Figure 1 The damper assembly 20 is shown as a monotube damper. However, the principles of the present disclosure may be applied to other types of dampers, such as a twin-tube damper.

[0039] like Figure 1As shown, the damper assembly 20 includes a housing 22 having a generally tubular shape, the housing 22 being annularly disposed about a central axis A and extending between a first end 24 and a second end 26. The housing 22 defines a fluid chamber 28 extending between the first end 24 and the second end 26 to accommodate a working fluid. A mounting ring 30 having a generally circular shape is disposed at the first end 24 of the housing 22 to attach the housing 22 to a vehicle. A piston 32 having a generally cylindrical shape is slidably disposed in the fluid chamber 28 and divides the fluid chamber 28 into a compression chamber 34 and a rebound chamber 36. The compression chamber 34 extends between the first end 24 and the piston 32. The rebound chamber 36 extends between the second end 26 and the piston 32.

[0040] A piston rod guide 38 is disposed in the rebound chamber 36 and is attached to the second end 26 to seal the fluid chamber 28. A piston rod 40 extends through the piston rod guide 38 along the central axis A and is attached to the piston 32 to move the piston 32 between the compression stroke and the rebound stroke. During the compression stroke, the piston 32 and the piston rod 40 move in the fluid chamber 28 toward the first end 24 of the housing 22. During the rebound stroke, the piston 32 and the piston rod 40 move in the fluid chamber 28 toward the second end 26 of the housing 22.

[0041] The term "compression" as used herein with respect to specific elements of the damper refers to those elements or portions of the elements that are adjacent to or facing the compression chamber 34, or in the case of a working fluid flow direction, refers to that flow direction that occurs during the compression stroke of the damper. Similarly, the term "rebound" as used herein with respect to specific elements of the damper refers to those elements or portions of the specific elements that are adjacent to or facing the rebound chamber 36, or in the case of a working fluid flow direction, refers to that flow direction that occurs during the rebound stroke of the damper.

[0042] Figure 2 A cross-sectional view of the piston 32 and the piston rod 40 including a pressure-sensitive relief valve 51 (also referred to as an adjustable pressure-sensitive relief valve) is shown. Figure 2 In the arrangement shown, the pressure sensitive relief valve 51 is integrated with the discharge piston valve. However, the pressure sensitive relief valve 51 can work with other types of piston valves (eg, caulking valves) or bottom valves of twin-tube shock absorbers.

[0043] like Figure 2 and Figure 3 As shown, the piston rod 40 includes a rod piston body 41 having a cylindrical shape and a rod extension 42 extending from the rod piston body 41 to a rod end 43 , the rod extension 42 having a substantially cylindrical shape with a diameter smaller than that of the rod piston body 41 .

[0044] Likewise Figure 2 and Figure 3As shown, the piston 32 includes a piston body 33 disposed around the rod extension 42 , and the piston body 33 has a substantially cylindrical shape. The piston body 33 of the piston 32 has a compression surface 331 facing the compression chamber 34 and a rebound surface 332 facing the rebound chamber 36 .

[0045] The piston body 33 defines a plurality of passages 72, 74, 76 to allow working fluid to flow through the piston 32 during the compression stroke and the rebound stroke. According to an embodiment of the present disclosure, the piston body 33 defines at least one compression passage 72, at least one rebound passage 74, and at least one additional passage 76.

[0046] According to an embodiment of the present disclosure, the at least one compression channel 72 is radially spaced apart from the outer surface 78 of the piston body 33, and extends from the compression surface 331 and passes through the piston body 33. The at least one rebound channel 74 is circumferentially spaced apart from the at least one compression channel 72, and extends from the outer surface 78 toward the compression surface 331 at an oblique angle relative to the central axis A. The at least one additional channel 76 is radially located between the central axis A and the at least one compression channel 72 and radially located between the central axis A and the at least one rebound channel 74, and the at least one additional channel 76 extends along the piston body 33. The at least one compression channel 72 is in fluid communication with the at least one rebound channel 74 through the at least one additional channel 76.

[0047] According to an embodiment of the present disclosure, the piston body 33 defines a first groove 31 and a second groove 39, the at least one compression channel 72 is in fluid communication with the at least one additional channel 76 through the first groove 31, and the at least one rebound channel 74 is in fluid communication with the at least one additional channel 76 through the second groove 39. The first groove 31 extends around the central axis A and extends axially from the rebound surface 332 to the at least one additional channel 76. The second groove 39 extends around the central axis A and extends axially from the compression surface 331 to the at least one additional channel 76. In other words, the at least one additional channel 76 is axially located between the first groove 31 and the second groove 39. The first groove 31 and the second groove 39 are radially located between the central axis A and the at least one compression channel 72 and radially located between the central axis A and the at least one rebound channel 74. The at least one rebound channel 74 extends from the outer surface 78 to the second groove 39.

[0048] According to Figure 2 and Figure 3In the embodiment of the present disclosure shown, the at least one compression channel 72 includes a plurality of compression channels 72. The plurality of compression channels 72 are positioned around the central axis A and are spaced apart from each other in the circumferential direction. The compression channel 72 extends in a parallel relationship with the central axis A. The at least one rebound channel 74 includes a plurality of rebound channels 74. The plurality of rebound channels 74 are positioned around the central axis A and are spaced apart from each other in the circumferential direction. Each rebound channel 74 in the plurality of rebound channels 74 is located between adjacent compression channels 72 in the plurality of compression channels 72 in the circumferential direction. The rebound channel 74 extends at an inclination angle α relative to the central axis A. According to an embodiment of the present disclosure, the inclination angle α is less than 90°. The at least one additional channel 76 includes a plurality of additional channels 76, each of which extends along the piston body 33 in a parallel relationship with the central axis A. The plurality of additional channels 76 are radially located between the central axis A and the compression channel 72, and are spaced apart from each other in the circumferential direction around the central axis A. In other words, the additional channel 76 is closer to the central axis A than the compression channel 72 and the rebound channel 74.

[0049] like Figure 2 and Figure 3 As shown, the piston 32 includes a compression valve 4 located on the rebound surface 332. The compression valve 4 covers the at least one compression channel 72 (i.e., if there is more than one compression channel 72, the compression valve 4 covers all the compression channels 72) to adjust the flow of the working fluid through the piston 32 during the compression stroke, thereby providing a damping force during the compression stroke. The piston 32 also includes a rebound valve 61, which is located on the compression surface 331 and covers the at least one rebound channel 74 (i.e., if there is more than one rebound channel 74, the rebound valve 61 covers all the rebound channels 74) to adjust the flow of the working fluid through the piston 32 during the rebound stroke, thereby providing a damping force during the rebound stroke. The at least one additional channel 76 is axially spaced from the compression valve 4 and axially spaced from the rebound valve 61.

[0050] like Figure 2 , Figure 3 and Figure 7As shown, the piston 32 includes a pressure-sensitive relief valve 51, which covers the at least one additional channel 76 (that is, if there is more than one additional channel 76, the pressure-sensitive relief valve 51 covers all additional channels 76), and the pressure-sensitive relief valve 51 includes a working disc group 53 and an outer disc 11 arranged radially outside the working disc group 53. The working disc group 53 is against the outer disc 11 in the radial direction and can deflect in two opposite directions along the central axis A to adjust the flow of the working fluid through the piston 32 during the compression stroke and the rebound stroke, thereby providing a damping force during the compression stroke and the rebound stroke. It can be understood that "can be deflected in two opposite directions along the central axis A" means that it can be deflected toward two opposite axial directions; for example, as Figure 2 As shown, the working disc set 53 can be deflected both downward and upward.

[0051] The outer disk 11 and the working disk group 53 are positioned relative to each other on a plane perpendicular to the central axis A by abutting against each other in the radial direction, which is different from the conventional compression valve or rebound valve (e.g., by a compression surface or a rebound surface) being positioned relative to each other in the axial direction. In other words, the disk with the largest diameter among the disks of the working disk group 53 is located at the center of the outer disk 11 in the radial direction. Such a design of the pressure-sensitive relief valve 51 in the present disclosure makes it sensitive to the pressure of the working fluid even if the pressure of the working fluid is small due to the low damper speed. For example, even if the outermost edge of the working disk group 53 is only slightly deflected due to the small working fluid pressure, the working fluid is allowed to flow between the outer disk 11 and the deflected working disk group 53, thereby providing a damping force during the compression stroke and the rebound stroke.

[0052] The working disk group 53 disconnects the fluid communication between the at least one compression channel 72 and the at least one rebound channel 74 by abutting against the outer disk 11, and opens the fluid communication between the at least one compression channel 72 and the at least one rebound channel 74 by deflecting in either of two opposite directions along the center axis A.

[0053] During the compression stroke, the working disc group 53 is easily deflected toward the compression chamber 34 in the direction along the center axis A by the working fluid pressure from the compression chamber 34, so as to allow the working fluid contained in the compression chamber 34 to flow toward the rebound chamber 36 through the at least one compression channel 72, the at least one additional channel 76 and the at least one rebound channel 74 in sequence, thereby providing damping force during the compression stroke.

[0054] During the rebound stroke, the working disk group 53 is easily deflected toward the rebound chamber 36 in the direction along the center axis A by the working fluid pressure of the working fluid from the rebound chamber 36, so as to allow the working fluid contained in the rebound chamber 36 to flow toward the compression chamber 34 through the at least one rebound channel 74, the at least one additional channel 76 and the at least one compression channel 72 in sequence, thereby providing damping force during the rebound stroke.

[0055] Figure 4 FIG. 1 is a graph of force versus velocity, wherein curve 100 shows the damping characteristics of a conventional valve, and shaded area 102 shows the adjustment range of the pressure sensitive relief valve of the present disclosure. Figure 4 As shown, curve 100 shows the damping characteristics of the conventional valve, that is, the damping force is close to zero in the ultra-low speed range and gradually increases slowly as the speed increases, and the flow characteristics in the lowest speed range cannot be adjusted. The shaded area 102 represents the adjustment range of the pressure-sensitive relief valve 51 of the present disclosure, indicating that the pressure-sensitive relief valve 51 is capable of providing an appropriate level of damping force from a speed close to zero, and the flow characteristics in the lowest speed range are adjustable, thereby improving the handling and ride comfort.

[0056] According to the embodiments of the present disclosure, Figure 3 and Figure 7 As shown, the working disk group 53 includes a main working disk 8, at least one rebound working disk 9 and at least one compression working disk 10. The main working disk 8 is against the outer disk 11 in the radial direction. The at least one compression working disk 10 is arranged on the surface of the main working disk 8 facing the compression chamber 34, and the outer diameter of the compression working disk 10 is smaller than the outer diameter of the main working disk 8. The at least one rebound working disk 9 is arranged on the other surface of the main working disk 8 facing the rebound chamber 36, and the outer diameter of the rebound working disk 9 is smaller than the outer diameter of the main working disk 8.

[0057] According to the embodiments of the present disclosure, Figure 2 and Figure 3 As shown, the pressure-sensitive relief valve 51 is axially located between the compression valve 4 and the at least one additional passage 76, and is axially spaced apart from the compression valve 4 and the at least one additional passage 76. In other words, there is space on both axial sides of the pressure-sensitive relief valve 51 to allow it to deflect in either of two opposite directions along the central axis A.

[0058] According to an embodiment of the present disclosure, the pressure-sensitive relief valve 51 is located in the first groove 31. Figure 2As shown, the piston body 33 has a surface 333, a surface 334 and a surface 335, the at least one additional channel 76 extends from the surface 333 toward the compression surface 331, and the surface 334 and the surface 335 are located between the rebound surface 332 and the surface 333 in the axial direction and are spaced apart from the rebound surface 332 and the surface 333 in the axial direction. The surface 334 and the surface 335 extend annularly around the central axis A and are perpendicular to the central axis A, and the surface 334 is spaced apart from the surface 335 in the radial direction. The outer disk 11 is located on the surface 334 and is clamped on the surface 334 by the mounting ring 6 having an inner diameter greater than the inner diameter of the outer disk 11. The working disk group 53 is located on the surface 335 and is clamped on the surface 335 via the gasket 7 having an outer diameter less than the outer diameter of the working disk group 53.

[0059] The piston body 33 also has a surface 336 axially located between the rebound surface 332 and the surface 334 and axially spaced from them. The support disc 5 is interposed between the compression valve 4 and the surface 336 and between the compression valve 4 and the gasket 7. A plurality of protrusions 71 circumferentially spaced from each other around the central axis A are provided on the surface 336 and in abutting relationship with the support disc 5 to provide a space 75 between the support disc 5 and the surface 336, thereby establishing fluid communication between the at least one compression channel 72 and the first groove 31 through the space 75. The outer diameter of the support disc 5 is larger than the outer diameter of the surface 336 and smaller than the outer diameter of the compression valve 4. The support disc 5 provides support for the compression valve 4 to prevent it from excessively deflecting toward the surface 336 of the piston body 33 during the rebound stroke.

[0060] According to the embodiments of the present disclosure, Figure 3 As shown, the compression valve 4 includes a plurality of disks, a retainer 2 and a gasket 3, and each disk has a substantially circular shape. The plurality of disks, the gasket 3 and the retainer 2 of the compression valve 4 are stacked on each other and sandwiched between the support disk 5 and the rod piston body 41.

[0061] According to an embodiment of the present disclosure, the rebound valve 61 defines a flow channel 73. When the rebound valve 61 is not deflected, the compression chamber 34 is connected to at least one rebound channel 74 through the flow channel 73 during the compression stroke and the rebound stroke, thereby expanding the adjustment range of the damping force of the damper assembly together with the pressure-sensitive relief valve 51 at low damper speeds.

[0062] The flow channel 73 may be formed by a plurality of radially outer recesses disposed on at least one disk of the rebound valve 61. Figure 2 and Figure 3 As best shown in FIG. 1 , the rebound valve 61 includes a main orifice disk 14 having a plurality of radially outer recesses 79 to form a flow channel 73. The rebound valve 61 may also include a working disk 15, and all the disks of the rebound valve 61 are stacked on top of each other and sandwiched between the compression surface 331 and the outer sleeve 17 of the piston 32. Figure 2 and Figure 3 As shown, the piston 32 further includes an inner sleeve 18, which is located inside the outer sleeve 17 and inserted into the second groove 39 without covering the at least one additional channel 76. An O-ring 16 is disposed between the rebound valve 61, the outer sleeve 17 and the inner sleeve 18 to provide a seal therebetween. The piston 32 further includes a spring 19, which is sleeved on the outside of the inner sleeve 18, one end of the spring 19 abuts against the outer sleeve 17 and the other end abuts against a spring bushing 21, which is fixed to the inner sleeve 18 and the rod extension 42.

[0063] The additional orifice disk 13 is sandwiched between the additional surface 337 of the piston body 33 and the end surface 181 of the inner sleeve 18 , and has a plurality of radially outer recesses 77 for controlling the flow of the working fluid between the second groove 39 and the at least one additional channel 76 .

[0064] Figure 5 A cross-sectional view of the piston 32 including the pressure sensitive relief valve 51 of the present disclosure is shown, and the oil flow path through the piston 32 during the rebound stroke and the compression stroke and at low damper speeds is shown.

[0065] like Figure 5 As shown in the figure (wherein arrows 50 and 52 indicate the flow of the working fluid), during the compression stroke, the piston rod 40 and the piston 32 move at a low speed toward the first end 24 of the housing 22. In response to the low-speed movement of the piston rod 40 and the piston 32, the working fluid contained in the compression chamber 34 is compressed into a low-pressure working fluid, and flows toward the rebound chamber 36 through the at least one compression passage 72, the pressure-sensitive relief valve 51 (whose working disc group 53 is deflected toward the piston body 33 by the low pressure of the working fluid from the compression chamber 34), the at least one additional passage 76, the recess 77 of the orifice disc 13, and the at least one rebound passage 74 in sequence, as shown by the arrow 50. At the same time, the working fluid contained in the compression chamber 34 also flows toward the rebound chamber 36 through the flow passage 73 and the at least one rebound passage 74 in sequence, as shown by the arrow 52.

[0066] Still Figure 5As shown in the figure (wherein arrows 54 and 55 indicate the flow of the working fluid), during the rebound stroke, the piston rod 40 and the piston 32 move at a low speed toward the second end 26 of the housing 22. In response to the low-speed movement of the piston rod 40 and the piston 32, the working fluid contained in the rebound chamber 36 is compressed to become a low-pressure working fluid, and flows toward the compression chamber 34 through the at least one rebound channel 74, the recess 77 of the orifice disk 13, the at least one additional channel 76, the pressure-sensitive relief valve 51 (whose working disk group 53 is deflected toward the support disk 5 by the low pressure of the working fluid from the rebound chamber 36) and the at least one compression channel 72 in sequence, as shown by the arrow 54. At the same time, the working fluid contained in the rebound chamber 36 also flows toward the compression chamber 34 through the at least one rebound channel 74 and the flow channel 73 in sequence, as shown by the arrow 55.

[0067] from Figure 5 It can be seen that the pressure sensitive relief valve 51 is able to provide damping for the low speed range of the damper during both the compression stroke and the rebound stroke.

[0068] Figure 6 A cross-sectional view of the piston 32 including the pressure sensitive relief valve 51 of the present disclosure is shown, and the oil flow path through the piston 32 during the rebound stroke and the compression stroke and at high damper speeds is shown.

[0069] like Figure 6 As shown in the figure (wherein arrows 52, 56, and 57 indicate the flow of the working fluid), during the compression stroke, the piston rod 40 and the piston 32 move toward the first end 24 of the housing 22 at a high speed. In response to the high-speed movement of the piston rod 40 and the piston 32, the working fluid contained in the compression chamber 34 is compressed into a high-pressure working fluid, and flows toward the rebound chamber 36 through the at least one compression channel 72, as shown by the arrow 56. At the same time, the working fluid contained in the compression chamber 34 also flows toward the rebound chamber 36 through the at least one compression channel 72, the pressure-sensitive relief valve 51 (whose working disc group 53 is deflected toward the piston body 33 by the high pressure of the working fluid from the compression chamber 34), the at least one additional channel 76, the recess 77 of the orifice disc 13, and the at least one rebound channel 74, as shown by the arrow 57. At the same time, the working fluid contained in the compression chamber 34 also flows toward the rebound chamber 36 through the recess 79 of the main orifice disc 14 and the at least one rebound channel 74, as shown by the arrow 52.

[0070] Still Figure 6As shown in the figure (wherein arrows 58 and 59 indicate the flow of the working fluid), during the rebound stroke, the piston rod 40 and the piston 32 move at a high speed toward the second end 26 of the housing 22. In response to the high-speed movement of the piston rod 40 and the piston 32, the working fluid contained in the rebound chamber 36 is compressed into a high-pressure working fluid, and flows toward the compression chamber 34 through the at least one rebound channel 74, as shown by the arrow 58. At the same time, the working fluid contained in the rebound chamber 36 flows toward the compression chamber 34 through the at least one rebound channel 74, the recess 77 of the additional orifice disk 13, the at least one additional channel 76, the pressure-sensitive relief valve 51 (whose working disk group 53 is deflected toward the support disk 5 by the high pressure of the working fluid from the rebound chamber 36) and the at least one compression channel 72 in sequence, as shown by the arrow 59.

[0071] from Figure 6 It can be seen that the pressure sensitive relief valve 51 is also able to provide damping for the high speed range of the damper during the compression stroke and the rebound stroke without negatively affecting the operation of the compression valve 4 and the rebound valve 61 .

[0072] The parallel arrangement of the pressure sensitive relief valve 51 relative to the main valves (i.e., the compression valve 4 and the rebound valve 61) means that it is not restricted when the shock absorber operates at high speeds. The pressure sensitive relief valve 51 provides improvements in vehicle dynamic characteristics while being easy to manufacture. The pressure sensitive relief valve 51 can also provide symmetrical operation during the compression stroke and the rebound stroke.

[0073] The foregoing description is not intended to be exhaustive or to limit the present disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but are interchangeable where applicable, even if not specifically shown or described, and may be used in selected embodiments, and may also be varied in a variety of ways. Such variations should not be considered as departing from the present disclosure, and all such variations are intended to be included within the scope of the present disclosure.

Claims

1. A damper assembly, characterized in that: include: a housing defining a fluid chamber extending along a central axis to contain a working fluid; a piston slidably disposed in the fluid chamber so as to divide the fluid chamber into a rebound chamber and a compression chamber; a piston rod extending along the central axis and coupled to the piston to move the piston between a compression stroke and a rebound stroke, wherein the piston defines at least one compression passage, at least one rebound passage, and at least one additional passage to allow the working fluid to flow through the piston during the compression stroke and the rebound stroke; a compression valve covering the at least one compression passage to regulate the flow of the working fluid through the piston during the compression stroke; a rebound valve covering the at least one rebound passage to regulate the flow of the working fluid through the piston during the rebound stroke; and A pressure-sensitive relief valve covers the at least one additional channel and includes at least one working disk and an outer disk arranged radially outside the at least one working disk, wherein the at least one working disk abuts against the outer disk in a radial direction and can deflect in two opposite directions along the central axis to regulate the flow of the working fluid through the piston during the compression stroke and the rebound stroke.

2. The damper assembly according to claim 1, characterized in that The at least one compression channel is in fluid communication with the at least one rebound channel through the at least one additional channel; and The at least one working disk cuts off the fluid communication by abutting against the outer disk and opens the fluid communication by deflecting in either of two opposite directions along the central axis.

3. The damper assembly according to claim 2, characterized in that The at least one additional passage is radially spaced apart from the at least one compression passage and radially spaced apart from the at least one rebound passage, and the at least one additional passage is axially spaced apart from the rebound valve and axially spaced apart from the compression valve; and The pressure-sensitive relief valve is axially located between the compression valve and the at least one additional passage, and the pressure-sensitive relief valve is axially spaced apart from the compression valve and the at least one additional passage.

4. The damper assembly according to claim 3, characterized in that The piston defines a first groove, the at least one compression passage is in fluid communication with the at least one additional passage through the first groove, and the pressure sensitive relief valve is located in the first groove.

5. The damper assembly according to claim 3, characterized in that The damper assembly further comprises: A support disk is disposed on a surface of the compression valve facing the pressure sensitive relief valve to support the compression valve and prevent the compression valve from excessively deflecting toward the pressure sensitive relief valve during the rebound stroke.

6. The damper assembly according to claim 1, characterized in that The rebound valve defines a flow passage through which the compression chamber communicates with the at least one rebound passage in an undeflected state of the rebound valve.

7. The damper assembly according to claim 6, characterized in that The flow passage is formed by a plurality of radially outer notches disposed on at least one disk of the rebound valve.

8. The damper assembly according to claim 6, characterized in that The piston defines a second groove, the at least one rebound passage is in fluid communication with the at least one additional passage through the second groove, and the flow passage is in fluid communication with the at least one additional passage through the second groove.

9. The damper assembly according to claim 1, characterized in that The at least one working disk comprises: A main working disk, the main working disk abuts against the outer disk in a radial direction; at least one compression working disk, which is disposed on a surface of the main working disk facing the compression chamber, and the outer diameter of the at least one compression working disk is smaller than the outer diameter of the main working disk; and At least one rebound working disk is arranged on the other surface of the main working disk facing the rebound chamber, and the outer diameter of the at least one rebound working disk is smaller than the outer diameter of the main working disk.

10. The damper assembly according to claim 1, characterized in that The damper assembly further comprises: a mounting ring, the outer disk being clamped on the piston via the mounting ring, and the inner diameter of the mounting ring being larger than the inner diameter of the outer disk; and A gasket, via which the at least one working disk is clamped on the piston, and an outer diameter of the gasket is smaller than an outer diameter of the at least one working disk.

11. A piston for a damper assembly, characterized in that: The piston comprises: a piston body defining at least one compression passage, at least one rebound passage, and at least one additional passage to allow a working fluid to flow through the piston body during a compression stroke and a rebound stroke; a compression valve covering the at least one compression passage to regulate the flow of the working fluid through the piston body during the compression stroke; a rebound valve covering the at least one rebound passage to regulate the flow of the working fluid through the piston body during the rebound stroke; and A pressure-sensitive relief valve covers the at least one additional channel and includes at least one working disk and an outer disk arranged radially outside the at least one working disk, wherein the at least one working disk abuts against the outer disk in a radial direction and can deflect in two opposite axial directions to regulate the flow of the working fluid through the piston body during the compression stroke and the rebound stroke.

12. The piston according to claim 11, characterized in that The at least one compression channel is in fluid communication with the at least one rebound channel via the at least one additional channel; and The at least one working disk cuts off the fluid communication by abutting against the outer disk, and opens the fluid communication by deflecting in either of the two opposite axial directions.

13. The piston according to claim 12, characterized in that The at least one additional passage is radially spaced apart from the at least one compression passage and radially spaced apart from the at least one rebound passage, and the at least one additional passage is axially spaced apart from the rebound valve and axially spaced apart from the compression valve; and The pressure-sensitive relief valve is axially located between the compression valve and the at least one additional passage, and the pressure-sensitive relief valve is axially spaced apart from the compression valve and the at least one additional passage.

14. The piston according to claim 13, characterized in that The piston body defines a first groove, the at least one compression passage is in fluid communication with the at least one additional passage through the first groove, and the pressure sensitive relief valve is located in the first groove.

15. The piston according to claim 13, characterized in that The piston further comprises: A support disk is disposed on a surface of the compression valve facing the pressure sensitive relief valve to support the compression valve and prevent the compression valve from excessively deflecting toward the pressure sensitive relief valve during the rebound stroke.

16. The piston according to claim 11, characterized in that The rebound valve defines a flow channel for connecting a compression chamber located on one side of the piston with the at least one rebound channel when the rebound valve is not deflected.

17. The piston according to claim 16, characterized in that The flow passage is formed by a plurality of radially outer notches disposed on at least one disk of the rebound valve.

18. The piston according to claim 16, characterized in that The piston body defines a second groove, the at least one rebound channel is in fluid communication with the at least one additional channel through the second groove, and the flow channel is in fluid communication with the at least one additional channel through the second groove.

19. The piston according to claim 11, characterized in that The at least one working disk comprises: A main working disk, the main working disk abuts against the outer disk in a radial direction; at least one compression working disk, which is disposed on a surface of the main working disk facing the rebound valve, and the outer diameter of the at least one compression working disk is smaller than the outer diameter of the main working disk; and At least one rebound working disk is disposed on the other surface of the main working disk facing the compression valve, and an outer diameter of the at least one rebound working disk is smaller than an outer diameter of the main working disk.

20. The piston according to claim 11, characterized in that The piston further comprises: a mounting ring, the outer disc being clamped on the piston body via the mounting ring, and the inner diameter of the mounting ring being larger than the inner diameter of the outer disc; and A washer, via which the at least one working disk is clamped on the piston body, and an outer diameter of the washer is smaller than an outer diameter of the at least one working disk.

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