Damper assembly

Abstract

A damper assembly includes a pressure tube forming a chamber, a piston assembly disposed in the chamber and dividing the chamber into two sub-chambers, and a piston rod fixed to the piston assembly. The piston assembly includes a body having a bore extending axially through the body. The piston assembly includes a discharge disc contacting the body at the bore and having a through-hole aligned with the bore. The piston rod extends through and concentrically contacts the bore and the through-hole. The body has a groove extending axially along a length of the bore. The groove and the piston rod form a passageway allowing fluid to travel through the body. The discharge disc has a notch extending from the through-hole and arranged to allow fluid from the passageway to pass through the discharge disc.

Description

Background Technology

[0001] Dampers are typically used in conjunction with a car's suspension system or other suspension systems to control the movement of a vehicle's wheels relative to the vehicle's body. To control movement, dampers are usually connected between the sprung (body) mass and the unsprung (suspension / drivetrain) mass of the vehicle.

[0002] A damper controls wheel movement by restricting the flow of fluid through its piston. As the damper moves toward a compression or extension position, fluid flows through the piston, for example, via a passage. This passage may have a fixed opening size. Movement resistance is provided by limiting the amount of fluid flowing through it. As the movement speed increases, the movement resistance may increase exponentially. Summary of the Invention

[0003] The damper assembly includes: a pressure tube forming a chamber and defining an axis; a piston assembly disposed within the chamber and dividing the chamber into two sub-chambers; and a piston rod extending along the axis and fixed to the piston assembly. The piston assembly includes a body having an inner bore extending axially from a first end through the body to a second end. The piston assembly includes a discharge disc contacting the body at the first end of the inner bore and having a through-hole aligned with the inner bore. The piston rod extends through and concentrically contacts the inner bore, and extends through and concentrically contacts the through-hole. One of the body or the piston rod has a groove extending axially along the inner bore from the first end to the second end. The body and the piston rod form a passage through the groove, allowing fluid to travel between the first and second ends. The discharge disc has a notch extending from the through-hole and arranged to allow fluid from the passage to pass through the discharge disc.

[0004] In one example, the body may include a lip at a first end of the bore that allows fluid to travel between the passage and the notch. The lip may extend completely around the first end of the bore.

[0005] In one example, the body may have a plurality of grooves including recesses that extend axially from a first end to a second end along an inner hole and that are circumferentially spaced apart from each other.

[0006] In one example, the discharge disc may have a plurality of notches including recesses that extend from the through-hole and that are circumferentially spaced apart from each other.

[0007] In one example, the body may include a through-hole extending through the body and allowing fluid to flow between sub-chambers, and the through-hole may be spaced apart from the inner bore. The cross-sectional area of ​​the through-hole may be larger than the cross-sectional area of ​​the notch. The body may include a plurality of through-holes, each of which may allow fluid to flow between sub-chambers, and these through-holes may be spaced apart from the inner bore and spaced apart from each other.

[0008] In one example, the damper assembly may further include multiple valve discs stacked on the discharge disc, such that the discharge disc is axially positioned between the valve discs and the body. The damper assembly may also include a pivot disc adjacent to the valve discs, such that the valve discs are axially positioned between the pivot disc and the body. The outer diameter of the pivot disc may be smaller than any of the outer diameters of the valve discs. A piston rod may extend through the valve discs and the pivot disc. The damper assembly may also include a preload ring axially positioned between the valve discs and the discharge disc. The inner diameter of the preload ring may be smaller than the outer diameter of the nearest disc of the valve discs, and the inner diameter of the preload ring may be smaller than the outer diameter of the discharge disc. The outer diameter of the preload ring may be at least as large as the outer diameter of the nearest disc of the valve discs.

[0009] In one example, the pressure tube can be cylindrical.

[0010] In one example, the body may have a first side axially facing the discharge disc, and the first side may include a central axial protrusion extending concentrically around an inner bore and contacting the discharge disc. The first side may include a plurality of peripheral axial protrusions radially spaced from the central axial protrusion, and the peripheral axial protrusions may contact the discharge disc. The discharge disc includes a cutout located radially outward of the central axial protrusion and radially inward of the peripheral axial protrusions. A notch may extend radially outward through the outer diameter of the central axial protrusion. Attached Figure Description

[0011] Figure 1 It is a perspective view of a vehicle with multiple damper assemblies.

[0012] Figure 2 This is a perspective view of one of the damper components in the damper assembly.

[0013] Figures 3A to 3C Commonly, these are exploded views of the piston assembly components of the damper assembly.

[0014] Figure 4 This is a perspective view of the main body of the piston assembly.

[0015] Figure 5 This is a perspective view of the alternative body of the piston assembly.

[0016] Figure 6 This is a perspective view of the discharge disc of the piston assembly.

[0017] Figure 7This is a perspective view of the replacement discharge disc of the piston assembly.

[0018] Figure 8 This is a cross-sectional view of the piston assembly.

[0019] Figure 9 It is a perspective cross-sectional view of the piston assembly body and the discharge disc.

[0020] Figure 10 This is another cross-sectional view of the piston assembly. Detailed Implementation

[0021] Referring to the accompanying drawings, in which like reference numerals denote like parts in several figures, a damper assembly 102 for a vehicle 100 includes a pressure tube 104, a piston assembly 110, and a piston rod 114. The pressure tube forms a chamber 106 and defines an axis A. The piston assembly is disposed within the chamber 106 and divides the chamber 106 into two sub-chambers 144, 146. The piston rod extends along axis A and is fixed to the piston assembly 110. The piston assembly 110 includes a body 116 having an inner bore 118 extending axially through the body 116 from a first end 120 to a second end 122. The piston assembly 110 includes a discharge disc 124 that contacts the body 116 at the first end 120 of the inner bore 118 and has a through hole 126 aligned with the inner bore 118. The piston rod 114 extends through and concentrically contacts the inner bore 118, and extends through and concentrically contacts the through hole 126. The body 116 has a groove 128 extending axially from a first end 120 to a second end 122 along an inner hole 118. The groove 128 and the piston rod 114 form a passage 130 that allows oil to travel between the first end 120 and the second end 122. The discharge disc 124 has a notch 132 that extends from the through hole 126 and is arranged to allow oil from the passage 130 to pass through the discharge disc 124.

[0022] The damping force provided by damper assembly 102 can be determined by the rate at which fluid moves between sub-chambers 144, 146 as piston assembly 110 moves. As piston assembly 110 moves, the volume of one sub-chamber 144, 146 increases while the volume of the other sub-chamber 144, 146 decreases, thereby guiding fluid from the decreasing sub-chamber 144, 146 to the increasing sub-chamber 144, 146. As piston assembly 110 slides through cylinder chamber 106, passage 130 and notch 132 provide a path for fluid movement between the two sub-chambers 144, 146. One benefit of damper assembly 102 is easier assembly, as recess 128 and piston rod 114 can form passage 130, regardless of the orientation of body 116 relative to piston rod 114. Another benefit is fine control over the rate at which fluid moves between sub-chambers 144, 146. During the design phase, the rate of fluid transfer can be controlled by adjusting the cross-sectional area of ​​the groove 128 and / or by changing the number of grooves 128.

[0023] refer to Figure 1 Vehicle 100 can be any passenger or commercial vehicle, such as cars, trucks, SUVs, crossovers, vans, minivans, taxis, buses, etc.

[0024] Vehicle 100 includes a frame 134. Vehicle 100 may be a unibody construction, wherein the frame 134 and body of vehicle 100 are a single component. Alternatively, vehicle 100 may be a body-on-frame construction, wherein the frame 134 supports the body as a separate component from the frame 134. The frame 134 and body may be formed from any suitable material (e.g., steel, aluminum, etc.).

[0025] Vehicle 100 includes wheels 136 that control the movement of vehicle 100 relative to the ground supporting vehicle 100 (e.g., acceleration, deceleration, steering, etc.). The vertical movement of wheels 136 relative to frame 134 affects the amount of traction between wheels 136 and the ground, as well as the amount of vertical acceleration experienced by the occupants of vehicle 100 when vehicle 100 is traveling on uneven surfaces, such as bumps, resulting in the riding sensation experienced by the occupants.

[0026] Vehicle 100 includes a suspension system 138. The suspension system 138 is coupled to a frame 134 and each wheel 136. The suspension system 138 absorbs and dampens shocks and vibrations transmitted from the wheels 136 to the frame 134. For each wheel 136, the suspension system 138 may include a coil spring 140 and a damper assembly 102. The damper assembly 102 extends through the coil spring 140. One end of the damper assembly 102 and the coil spring 140 is connected to the wheel 136 and moves with the wheel, and the other end of the damper assembly 102 and the coil spring 140 is connected to the frame 134 and moves with the frame.

[0027] The suspension system 138 is arranged such that upward movement of the wheel 136 (such as when the tire impacts a bulge while the vehicle 100 is moving) compresses the coil spring 140 and the damper assembly 102. The coil spring 140 can apply a force as a function (e.g., a linear relationship) of the difference between the current length of the coil spring 140 and the slack length of the coil spring 140. The damper assembly 102 can apply a force as a function of the compression or extension rate of the damper assembly 102.

[0028] refer to Figure 2 The damper assembly 102 can move from a compressed position to an extended position and vice versa. The distance between the mounting points 142 of the damper assembly 102 is smaller in the compressed position than in the extended position. A coil spring 140 or the like can push the damper assembly 102 toward the extended position. A force applied to the wheel 136 of the vehicle 100 (e.g., from bumps, potholes, etc.) can push the damper assembly 102 toward the compressed position.

[0029] Each damper assembly 102 controls the movement of the corresponding wheel 136 by restricting fluid flow into, out of, and / or between the sub-chambers 144, 146, such as between the compression sub-chamber 144 and the rebound sub-chamber 146. For example, when the damper assembly 102 moves toward a compression position or a extension position, the fluid movement is caused by the movement of the piston assembly 110 within the pressure tube 104 of the damper assembly 102.

[0030] The damper assembly 102 defines an axis A. Axis A extends between mounting points 142 of the damper assembly 102. The damper assembly 102 is elongated along axis A. The terms “axial,” “radial,” and “circumferential” as used herein are relative to axis A defined by the damper assembly 102.

[0031] Pressure tube 104 defines chamber 106. For example, pressure tube 104 may be hollow and tubular, such as cylindrical, thereby enclosing chamber 106 within it. Axis A may be defined by the cylindrical shape of pressure tube 104. Chamber 106 is filled with fluid (e.g., an incompressible hydraulic fluid such as oil). Movement of damper assembly 102 (e.g., to an extended or compressed position) may increase and / or decrease the fluid pressure in pressure tube 104 (e.g., in compression sub-chamber 144 and rebound sub-chamber 146). Pressure tube 104 may extend along axis A of damper assembly 102. Pressure tube 104 may be metallic or any suitable material.

[0032] The damper assembly 102 includes a piston rod 114 extending away from and movable relative to the pressure tube 104. The piston rod 114 is elongated along axis A of the damper assembly 102. The piston rod 114 is fixed to the piston assembly 110. As the damper assembly 102 moves toward a compressed or extended position, the piston rod 114 moves together with the piston assembly 110 relative to the pressure tube 104. The piston rod 114 may extend from within a chamber 106 of the pressure tube 104 to outside the chamber 106, for example, extending from the piston assembly 110 and through the return spring chamber 146.

[0033] Piston assembly 110 divides chamber 106 of pressure tube 104 into a compression sub-chamber 144 and a rebound sub-chamber 146, i.e., along axis A, compression sub-chamber 144 is on one side 158, 160 of piston assembly 110, while rebound sub-chamber 146 is on the opposite side 158, 160 of piston assembly 110. The outer circumferential surface 148 of piston assembly 110 (e.g., body 116) can be sealed to the inner surface of pressure tube 104. Piston assembly 110 can slide along axis A within chamber 106 of pressure tube 104. Sliding piston assembly 110 along axis A changes the volume of compression sub-chamber 144 and rebound sub-chamber 146. For example, when damper assembly 102 moves toward the compression position, the volume of compression sub-chamber 144 can decrease, and the volume of rebound sub-chamber 146 can increase. As another example, when the damper assembly 102 moves toward the extended position, the volume of the rebound chamber 146 may decrease, and the volume of the compression chamber 144 may increase. The piston assembly 110 is connected to the piston rod 114 such that the piston assembly 110 and the piston rod 114 move substantially in tandem. The piston assembly 110 may be secured to the piston rod 114, for example, via fasteners 150 and / or other suitable structures such as welding, friction fit, etc. The piston assembly 110 may be made of metal, plastic, or any suitable material.

[0034] refer to Figures 3A to 3CThe piston assembly 110 includes a body 116 and at least one discharge disc 124. For example, the piston assembly 110 may include a body 116 and a discharge disc 124 on each side 158, 160 of the body 116. The piston assembly 110 may also include a preload ring 152, a plurality of valve discs 154, a pivot disc 156, a preload gasket 176, and fasteners 150 on each side 158, 160 of the body 116, stacked, for example, starting from the body 116 in this order. A piston rod 114 may extend through and concentrically contact an inner bore 118 of the body 116, and may extend through and concentrically contact a through-hole 126 of the discharge disc 124. The piston rod 114 may further extend through the valve disc 154, the pivot disc 156, the preload gasket 176, and the fasteners 150. The valve disc 154, the pivot disc 156, and the preload gasket 176 may be radially symmetrical and centered on axis A.

[0035] refer to Figures 4 to 5 The piston assembly 110 includes a body 116. The body 116 may have a generally short, stout cylindrical shape, with an axial thickness less than the diameter of any of the disks 124, 154, and 156, but significantly greater than their thickness. The body 116 may include an inner bore 118, an outer circumferential surface 148, a first side 158, and a second side 160. The first side 158 and the second side 160 may each extend radially outward from the inner bore 118 to the outer circumferential surface 148. The first side 158 and the second side 160 may be opposite each other along axis A. The first side 158 and the second side 160 may axially face the corresponding discharge disk 124, such as... Figures 3A to 3C As shown. The first side 158 may face the return chamber 146, and the second side 160 may face the compression chamber 144.

[0036] An inner bore 118 extends axially through the body 116 from a first end 120 to a second end 122. The first end 120 may be the outlet of the inner bore 118 at a first side 158 of the body 116, and the second end 122 may be the outlet of the inner bore 118 at a second side 160 of the body 116. The inner bore 118 may have a constant cross-sectional shape from the first end 120 to the second end 122. For example, the inner bore 118 may have a cylindrical shape with a constant diameter from the first end 120 to the second end 122. The diameter of the inner bore 118 may be approximately equal to the diameter of the piston rod 114, thereby preventing fluid from flowing between the inner bore 118 and the piston rod 114.

[0037] The body 116 has at least one groove 128 extending axially from a first end 120 to a second end 122 along an inner bore 118, for example, multiple grooves 128. For example, each groove 128 may be a channel having a depth extending radially outward from the inner bore 118. Alternatively, the piston rod 114 may include grooves 128, in which case each groove 128 may be a channel having a depth extending radially inward from the outer surface of the piston rod 114. In either case, the grooves 128 may extend parallel to axis A. In the case of multiple grooves 128, the grooves 128 are circumferentially spaced from each other. Each groove 128 may have a constant cross-sectional shape from the first end 120 to the second end 122 and may terminate at both the first end 120 and the second end 122. The body 116 and piston rod 114 form a passage 130 through each groove 128, thereby allowing fluid to travel between the first end 120 and the second end 122, i.e., from the first end 120 to the second end 122, or vice versa.

[0038] The body 116 may include a lip 162 located at a first end 120 and a second end 122 of the inner bore 118, for example, one lip 162 at the first end 120 and one lip 162 at the second end 122. Each lip 162 may extend completely around the first end 120 or the second end 122 of the inner bore 118, for example, forming a circle centered on axis A. The lip 162 may have a width extending radially outward from the inner bore 118, i.e., having a width greater than the diameter of the inner bore 118. Each lip 162 may have a constant cross-section that projects circumferentially around the first end 120 or the second end 122. Each lip 162 allows fluid to travel between the passage 130 formed by the groove 128 and the recess 132 of the discharge disc 124. Each lip 162 may form a passage with the piston rod 114 and the discharge disc 124. Fluid exiting the groove 128 may then travel circumferentially around the piston rod 114 until the fluid reaches one of the recesses 132. Because the lip 162 extends completely around the first end 120 or the second end 122 of the inner hole 118, the notch 132 can be located at any circumferential position relative to the groove 128.

[0039] The first side 158 and the second side 160 may each include a base surface 164 and features 166, 168 extending axially from the base surface 164 toward a discharge disc 124 located near the body 116 on that side 158, 160. The base surface 164 may define a plane perpendicular to axis A. For example, the first side 158 and the second side 160 may each include a central axial protrusion 166 extending concentrically around an inner bore 118. The central axial protrusion 166 may have a height extending axially from the base surface 164 and a width extending radially outward from the inner bore 118. The height and / or width around the inner bore 118 may be constant. A lip 162 may be located in the central axial protrusion 166. The central axial protrusion 166 may contact the corresponding discharge disc 124, for example, by making its height at least as large as the height of any other features 166, 168 extending from the corresponding base surface 164.

[0040] The first side 158 and the second side 160 may each include a plurality of peripheral axial protrusions 168 radially spaced apart from a corresponding central axial protrusion 166. The peripheral axial protrusions 168 may be circumferentially spaced apart from each other on each side 158, 160 of the body 116. The peripheral axial protrusions 168 may interface with the outer circumferential surface 148. When the discharge disc 124 is in the relaxed position, the peripheral axial protrusions 168 may contact the corresponding discharge disc 124, for example, by making their height equal to the height of the corresponding central axial protrusion 166.

[0041] The body 116 includes one or more protruding channels 170. Each protruding channel 170 extends from one of the peripheral axial protrusions 168 on one side 158, 160 of the body 116 to a base surface 164 on the other side 158, 160 of the body 116, i.e., from one of the peripheral axial protrusions 168 on the first side 158 to the base surface 164 on the second side 160, or vice versa. The protruding channel 170 provides fluid communication between the compression chamber 144 and the rebound chamber 146 of the pressure tube 104, so that fluid can flow from the compression chamber 144 to the rebound chamber 146, or vice versa.

[0042] refer to Figure 4The body 116 includes one or more through-holes 172 extending through the body 116 and allowing fluid to flow between sub-chambers 144, 146. The through-holes 172 are radially spaced from the inner bore 118. The through-holes 172 may be circumferentially and / or radially spaced from each other and / or circumferentially and / or radially spaced from the protruding passage 170. The through-holes 172 provide fluid communication between the compression sub-chamber 144 and the rebound sub-chamber 146 of the pressure tube 104, allowing fluid to flow from the compression sub-chamber 144 to the rebound sub-chamber 146, or vice versa. Each through-hole 172 may have a cross-sectional area larger than that of each recess 132. During design, modifying the number and cross-sectional area of ​​the through-holes 172 can provide a wide range of potential flow velocities through the body 116. The combination of the recess 128 and the through-holes 172 can provide fine control over the flow rate over a wide range of flow rates.

[0043] refer to Figure 5 The peripheral axial protrusion 168 may include a notch 174 that allows fluid from the protrusion passage 170 to flow below the height of the peripheral axial protrusion 168 to the outside of the peripheral axial protrusion 168. Therefore, fluid can flow through the notch 174 even if the discharge disc 124 is adjacent to the peripheral axial protrusion 168. The size of the notch 174 can be used to adjust the flow rate through the piston assembly 110.

[0044] refer to Figures 6 to 7 The discharge plate 124 may be a circular plate. The diameter of the discharge plate 124 may be slightly smaller than the diameter of the outer circumferential surface 148 of the body 116, thereby allowing fluid in the space between the discharge plate 124 and the base surface 164 to flow around the discharge plate to the corresponding sub-chambers 144, 146. The discharge plate 124 may have a constant axial thickness. Each discharge plate 124 includes a corresponding through hole 126. The through hole 126 may be circular in shape and may be located at the center of the discharge plate 124. The diameter of the through hole 126 may be approximately equal to the diameter of the piston rod 114 (and the diameter of the inner bore 118), thereby preventing fluid from flowing between the through hole 126 and the piston rod 114. The through hole 126 is aligned with the inner bore 118, for example, the through hole 126 and the inner bore 118 are centered on axis A.

[0045] The discharge disc 124 reduces movement resistance in response to fluid flow through it and / or the difference in fluid pressure on one side of the discharge disc 124 relative to the opposite side. Fluid flow and / or fluid pressure difference can cause the discharge disc 124 to translate or flex, creating an axial clearance 178 through which fluid can flow and / or increasing the size of this axial clearance. Increasing the size of the axial clearance 178 reduces movement resistance by allowing a larger amount of fluid to flow from one sub-chamber 144, 146 to the other sub-chamber 144, 146. The amount of flexure and / or translation of the discharge disc 124, and the resulting increase in the size of the axial clearance 178, can be proportional to the fluid velocity and / or pressure difference between the compression sub-chamber 144 and the rebound sub-chamber 146. For example, a greater fluid velocity and / or fluid pressure difference results in a greater amount of flexure and / or translation of the discharge disc 124 away from the body 116, thereby providing a greater increase in the size of the axial clearance 178 between the discharge disc and the body. A threshold fluid flow rate and / or fluid pressure difference may be required to cause the discharge disc 124 to flex and / or translate. The discharge disc 124 may not reduce its movement resistance until the threshold fluid flow rate and / or fluid pressure difference is reached.

[0046] Each discharge disc 124 includes at least one recess 132 extending from a through-hole 126, for example, multiple recesses 132. The recesses 132 extend through the discharge disc 124 and thus allow fluid to pass through the discharge disc 124. The recesses 132 may be circumferentially spaced from each other, thereby allowing fluid to travel a shorter path from one recess in the groove 128 to one recess in the recess 132. The recesses 132 may extend radially outward from the through-hole 126, for example, radially outward across the outer diameter of the central axial protrusion 166. Fluid from the lip 162 of the body 116 may thus flow into the recesses 132 and travel outside the central axial protrusion 166 into the space between the base surface 164 and the discharge disc 124. The recesses 132 are continuously open, i.e., independent of the position of other components of the damper assembly 102, and the flow is limited by the cross-sectional area of ​​the recesses 132. The cross-sectional area of ​​one of the notches 132 is the area within the notch 132 and radially outward of the through hole 126 in a plane perpendicular to axis A. During design, even if the groove 128 remains the same, the cross-sectional area of ​​the notch 132 can be used to adjust the flow rate of fluid through the piston assembly 110, so the same body 116 can be used in damper assemblies 102 with different flow rates.

[0047] Each discharge disc 124 includes at least one cutout 180. The cutout 180 extends through the discharge disc 124. The cutouts 180 may be spaced apart from each other. For example, the cutouts 180 of each discharge disc 124 may be circumferentially spaced apart from each other and radially overlapping, as... Figure 6As shown, this refers to overlapping ranges located in different circumferential ranges and radii. For another example, the cuts 180 of each discharge disc 124 may overlap circumferentially, meaning two or more cuts 180 may overlap along a common radius extending from axis A, as shown... Figure 7 As shown in the diagram. These cuts 180 may be spaced apart from each other along a common radius. Cuts 180 may be positioned radially outward of the central axial protrusion 166 and radially inward of the peripheral axial protrusion 168. Cuts 180 may be positioned radially and circumferentially above the base surface 164 of the corresponding sides 158, 160 of the body 116, i.e., aligned with the base surface 164 along axis A. Cuts 180 may reduce the stiffness of the corresponding discharge disc 124. The positioning of cuts 180 helps control the stiffness of the discharge disc 124 to allow the discharge disc 124 to deflect away from the peripheral axial protrusion 168, as described below.

[0048] Discharge discs 124 at each side 158, 160 of the body 116 may be spaced apart from base surfaces 164 on those sides 158, 160, for example, at through-holes 172 and / or at the end of the protrusion channel 170 terminating at the base surface 164. Spaced apart from the base surface 164 at through-holes 172, fluid flows freely into and out of the through-holes 172, for example, without being impeded by the discharge discs 124. Spaced apart from one end of the protrusion channel 170, fluid flows freely into the protrusion channel 170 on that side of the body 116, for example, without being impeded by the discharge discs 124.

[0049] The discharge discs 124 at each side 158, 160 of the main body 116 selectively allow fluid to exit the protrusion channel 170 at the end terminating at the peripheral axial protrusion 168, depending on the amount and direction of the fluid pressure applied to the discharge discs 124. The discharge discs 124 selectively allow fluid flow by controlling the size of the axial clearance 178 between the discharge discs 124 and the peripheral axial protrusion 168, at which the protrusion channel 170 terminates. Thus, the same component performs the different tasks of allowing fluid to flow through the notch 132 and selectively allowing fluid to flow through the protrusion channel 170, thereby reducing the number of components in the damper assembly 102.

[0050] When the damper assembly 102 is in a neutral state, i.e., not moving toward the extended or compressed position, the discharge discs 124 on each side 158, 160 of the body 116 cover one end of the protrusion channel 170 and restrict or inhibit fluid inflow into and out of the protrusion channel 170. Fluid can still flow through the notch 174 (if present) at a reduced rate compared to the discharge discs 124 deflected away from the corresponding peripheral axial protrusions 168. The discharge discs 124 in the neutral state may abut, for example, the peripheral axial protrusions 168 surrounding the open end of the protrusion channel 170.

[0051] As the damper assembly 102 moves toward the compression or extension position, the discharge disc 124, facing the opposite direction of movement to the body 116, can be moved away from the body 116 (e.g., away from the peripheral axial protrusion 168) by the pressure difference and / or fluid flow generated by this movement. This movement of the discharge disc 124 away from the body 116 creates an axial gap 178 between the peripheral axial protrusion 168 of the body 116 and the discharge disc 124. Fluid can flow through the axial gap 178 from the protrusion passage 170 to the corresponding sub-chambers 144, 146.

[0052] When the damper assembly 102 moves toward the compression position or the extension position, it can push the discharge disc 124 toward the body 116 in the direction of movement of the body 116 without forming or widening the axial gap 178 between the peripheral axial protrusion 168 of the body 116 and the discharge disc 124.

[0053] refer to Figure 8 The damper assembly 102 may include one or more valve discs 154, such as one or more valve discs 154 on each side 158, 160 of the body 116. On each side 158, 160 of the body 116, the valve discs 154 may be stacked on a corresponding discharge disc 124 such that the discharge disc 124 is axially positioned between the valve disc 154 and the body 116. The valve disc 154 may be supported by a piston rod 114. For example, the piston rod 114 may extend through a central opening in the valve disc 154.

[0054] The valve disc 154 is elastically deformable. For example, a force applied to the outer edge of the valve disc 154 can cause the valve disc 154 to flex, causing the outer edge to move axially relative to the corresponding central opening of the valve disc 154. The valve disc 154 is made of an elastically deformable material (e.g., spring steel, plastic with suitable elastic properties, etc.).

[0055] On each side 158, 160 of the main body 116, the valve disc 154 pushes the discharge disc 124 on that side 158, 160 toward the main body 116, that is, the valve disc 154 increases the amount of force required to flex the discharge disc 124 away from the corresponding peripheral axial protrusion 168.

[0056] The dimensions of the valve disc 154 may gradually decrease (or alternatively, decrease and then increase) with distance from the body 116 along axis A. For example, the outer diameter of the valve disc 154 closest to the body 116 may be larger than the outer diameter of the valve disc 154 adjacent to it, and so on. The diameter of the valve disc 154 furthest from the body 116 may be smaller than the diameter of the other valve discs 154 on that side 158, 160 of the body 116. As another example, the valve disc 154 may be configured similarly to a leaf spring.

[0057] The valve disc 154 closest to the body 116 may be adjacent to the corresponding discharge disc 124 close to the piston rod 114. The valve disc 154 closest to the body 116 may be spaced apart from the discharge disc 124 at its radially outer edge. For example, a preload ring 152 on each side 158, 160 of the body 116 may be axially positioned along axis A between the valve disc 154 (e.g., the closest valve disc 154) on that side 158, 160 of the body 116 and the discharge disc 124. The preload ring 152 may be circular or any suitable shape. The inner diameter of the preload ring 152 may be smaller than the outer diameter of the closest valve disc 154 and smaller than the outer diameter of the corresponding discharge disc 124. The outer diameter of the preload ring 152 may be at least as large as the outer diameter of the closest valve disc 154. The preload ring 152 may be located radially outside the cutout 180 of the discharge disc 124. The preload ring 152 can be made of metal, plastic, or any suitable material. The preload ring 152 provides internal preload to the valve disc 154.

[0058] Each damper assembly 102 may include a pair of pivot disks 156. Pivot disks 156 provide a pivot point for valve disks 154. For example, one pivot disk of the pivot disks 156 may be adjacent to a valve disk 154 such that the valve disk 154 on that side 158, 160 of the body 116 is axially positioned between the pivot disk 156 and the body 116, for example, adjacent to the smallest valve disk 154 on each side 158, 160 of the body 116 opposite the adjacent larger valve disk 154. The outer diameter of such pivot disk 156 may be smaller than the outer diameter of the adjacent smallest valve disk 154, i.e., smaller than any of the outer diameters of the valve disks 154 on that side 158, 160 of the body 116.

[0059] Each damper assembly 102 may include a pair of preload washers 176. The preload washers 176 protect the valve disc 154. The preload washers 176 sandwich the body 116, the disc, and other components of the damper assembly 102 supported by the piston rod 114. The thickness of the preload washers 176 can increase or decrease the available space for the disc, piston, etc. For example, the preload washers 176 on each side 158, 160 of the body 116 may be located axially outside the pivot disc 156 on that side 158, 160 of the body 116. Fasteners 150 may be attached to the piston rod 114 axially outside the preload washers 176 on that side 158, 160 of the body 116. Fasteners 150 may be, for example, threaded lock nuts. Fasteners 150 may constrain the preload washers 176, discharge disc 124, valve disc 154, body 116, etc., into a stack with a predetermined length.

[0060] refer to Figure 9 When the piston assembly 110 moves toward the compression position or the extension position, the passage 130 defined by the groove 128 and the piston rod 114 provides a flow path for fluid to move between the compression sub-chamber 144 and the rebound sub-chamber 146. For example, fluid in the space between the discharge disc 124 on one side 158, 160 of the body 116 and the base surface 164 of the body 116 travels through the notch 132 to the lip 162 on the radially outer side of the central axial protrusion 166 to the radially inner side of the central axial protrusion 166, then travels circumferentially around the piston rod 114 through the lip 162 to a groove in the recess 128, then travels axially along the groove 128 to the lip 162 on the opposite side 158, 160 of the body 116, then travels circumferentially along the lip 162 to a notch 132 on the same side 158, 160 of the body 116, and then travels radially outward through the notch 132 to the space between the other discharge disc 124 on the same side 158, 160 of the body 116 and the base surface 164. The space between the discharge disc 124 and the base surface 164 on each side 158, 160 of the main body 116 is in fluid communication with the corresponding sub-chambers 144, 146 surrounding the outer diameter of the discharge disc 124.

[0061] refer to Figure 10 When the piston assembly 110 moves toward the compression or extension position, the through-hole 172 provides a flow path for fluid to move between the compression sub-chamber 144 and the rebound sub-chamber 146. For example, fluid in the space between the discharge disc 124 on one side 158, 160 of the body 116 and the base surface 164 of the body 116 travels through the through-hole 172 to the space between the other base surface 164 and the other discharge disc 124.

[0062] As the piston assembly 110 moves toward the compression or extension position, the protrusion passage 170 provides a flow path for fluid to move between the compression sub-chamber 144 and the rebound sub-chamber 146. For example, fluid in the space between the discharge disc 124 on one side 158, 160 of the body 116 and the base surface 164 of the body 116 travels through the protrusion passage 170 having an end located at the base surface 164. If the fluid pressure difference between the sub-chambers 144, 146 is greater than a threshold difference of the discharge disc 124, the opposing discharge disc 124 flexes away from the peripheral axial protrusion 168 on the opposing side 158, 160 of the body 116. The fluid in the protrusion passage 170 then travels out of the protrusion passage 170 into the opposing sub-chambers 144, 146. If the peripheral axial protrusion 168 includes a notch 174, fluid can exit the protrusion passage 170 through the notch 174 even if the pressure difference is below the threshold.

[0063] This disclosure has been described in an illustrative manner, and it should be understood that the terminology used is intended to be descriptive rather than limiting. The adjectives “first” and “second” are used throughout this document as identifiers and are not intended to indicate importance, order, or quantity. Based on the foregoing teachings, numerous modifications and variations of this disclosure are possible, and this disclosure can be practiced in ways other than those specifically described.

Claims

1. A damper assembly comprising: a pressure tube forming a chamber and defining an axis; a piston assembly disposed in the chamber and dividing the chamber into two sub-chambers; and a piston rod elongated along the axis and fixed to the piston assembly; the piston assembly including a body having a bore axially extending through the body from a first end to a second end; the piston assembly including a discharge disc contacting the body at the first end of the bore and having a through-hole aligned with the bore; the piston rod extending through and concentrically contacting the bore, and extending through and concentrically contacting the through-hole; one of the body or the piston rod having a groove axially extending along the bore from the first end to the second end; the body and the piston rod forming a passageway through the groove, the passageway allowing fluid to travel between the first end and the second end; the discharge disc having a recess extending from the through-hole and arranged to allow fluid from the passageway to pass through the discharge disc; the body having a first side axially facing the discharge disc, the first side including a central axial protrusion extending concentrically around the bore and contacting the discharge disc; and the recess extending radially outward past an outer diameter of the central axial protrusion.

2. The damper assembly of claim 1, wherein the body includes a lip at the first end of the bore, the lip allowing fluid to travel between the passageway and the recess.

3. The damper assembly of claim 2, wherein the lip extends completely around the first end of the bore.

4. The damper assembly of claim 1, wherein the body has a plurality of grooves including the groove, the grooves axially extending along the bore from the first end to the second end, and the grooves being circumferentially spaced apart from one another.

5. The damper assembly of claim 1, wherein the discharge disc has a plurality of recesses including the recess, the recesses extending from the through-hole, and the recesses being circumferentially spaced apart from one another.

6. The damper assembly of claim 1, wherein the body includes a through-hole extending through the body and allowing fluid to flow between the sub-chambers, and the through-hole is spaced apart from the bore.

7. The damper assembly of claim 6, wherein a cross-sectional area of the through-hole is greater than a cross-sectional area of the recess.

8. The damper assembly of claim 6, wherein the body includes a plurality of through-holes including the through-hole, the through-holes each allowing fluid to flow between the sub-chambers, the through-holes being spaced apart from the bore, and the through-holes being spaced apart from one another.

9. The damper assembly of claim 1, further comprising a plurality of valve discs stacked on the discharge disc, such that the discharge disc is axially between the plurality of valve discs and the body.

10. The damper assembly of claim 9, further comprising a fulcrum disc abutting the plurality of valve discs, such that the plurality of valve discs are axially located between the fulcrum disc and the main body.

11. The damper assembly of claim 10, wherein an outer diameter of the fulcrum disc is less than any of the outer diameters of the plurality of valve discs.

12. The damper assembly of claim 10, wherein the piston rod extends through the plurality of valve discs and the fulcrum disc.

13. The damper assembly of claim 9, further comprising a pre-tension ring axially positioned between the plurality of valve discs and the drain disc.

14. The damper assembly of claim 13, wherein an inner diameter of the pre-tension ring is less than an outer diameter of a valve disc of the plurality of valve discs axially closest to the main body of the piston assembly, and the inner diameter of the pre-tension ring is less than an outer diameter of the drain disc.

15. The damper assembly of claim 13, wherein an outer diameter of the pre-tension ring is at least as large as an outer diameter of a valve disc of the plurality of valve discs axially closest to the main body of the piston assembly.

16. The damper assembly of claim 1, wherein the pressure tube is cylindrical.

17. The damper assembly of claim 1, wherein the first side includes a plurality of peripheral axial projections radially spaced from the central axial projection, and the peripheral axial projections contact the drain disc.

18. The damper assembly of claim 17, wherein the drain disc includes a cutout positioned radially outward of the central axial projection and radially inward of the peripheral axial projections.

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