Damper assembly with accumulator

Abstract

A method for assembling a damper assembly includes securing a damper interface to an outer surface of a pressure tube. The method includes securing an accumulator interface to an outer surface of an accumulator tube. The method includes, after securing the damper interface to the pressure tube and securing the accumulator interface to the accumulator tube, securing the pressure tube to the accumulator tube by pressure fitting the damper interface to the accumulator interface.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to dampers. More particularly, the present disclosure relates to damper assemblies including accumulators and methods for assembling damper assemblies. BACKGROUND

[0002] Dampers are commonly used in conjunction with automotive suspension systems or other suspension systems to control the motion of the wheels of a vehicle relative to the body of the vehicle. To control the motion, a damper is typically connected between the sprung (body) mass and the unsprung (suspension / driveline) mass of the vehicle. SUMMARY

[0003] According to one aspect of the present disclosure, a method for assembling a damper assembly includes securing a damper interface to an outer surface of a pressure tube and securing an accumulator interface to an outer surface of an accumulator tube. Then, after securing the damper interface to the pressure tube and securing the accumulator interface to the accumulator tube, the method includes securing the pressure tube to the accumulator tube by pressure fitting the damper interface to the accumulator interface. The pressure fitting maintains the positioning of the accumulator relative to the pressure tube, for example while the damper interface and the accumulator interface are further secured and without the need for clamps or other tools to hold the accumulator and / or pressure tube in place. The damper interface and the accumulator interface can be further secured, for example via laser welding.

[0004] According to another aspect of the present disclosure, a damper assembly includes an elongated pressure tube having a first outer surface, a damper interface secured to the first outer surface, an accumulator having a second outer surface, and an accumulator interface secured to the second outer surface, the accumulator interface pressure fitted with the damper interface.

[0005] According to one embodiment of the present invention, the pressure fitting of the accumulator interface with the damper interface includes an interference fit between the damper interface and the accumulator interface.

[0006] According to one embodiment of the present invention, the damper interface includes a first tapered interface surface and the accumulator interface includes a second tapered interface surface abutting the first tapered interface surface.

[0007] According to one embodiment of the present invention, the pressure tube defines a first chamber and the accumulator defines a second chamber, and the first chamber and the second chamber are in fluid communication via the accumulator interface and the damper interface.

[0008] According to one embodiment of the present invention, the accumulator interface is welded to the damper interface.

[0009] According to one embodiment of the present invention, the damper interface surrounds the accumulator interface.

[0010] According to one embodiment of the present application, the damper assembly further comprises a damper cap secured to the damper interface and the first outer surface of the pressure tube, the damper cap positioned between the damper interface and the first outer surface of the pressure tube.

[0011] According to one embodiment of the present application, the damper cap surrounds the damper interface.

[0012] According to one embodiment of the present application, wherein the damper cap comprises a surface complementary to the first outer surface of the pressure tube.

[0013] According to one embodiment of the present application, wherein the damper cap is welded to the damper interface between the damper cap and the pressure tube. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a perspective view of a vehicle having a plurality of damper assemblies.

[0015] Figure 2 is a cross-sectional view of one of the damper assemblies.

[0016] Figure 3 is a perspective view of the damper interface and the damper cap of the damper assembly.

[0017] Figure 4 is a perspective view of the accumulator interface and the accumulator cap of the damper assembly.

[0018] Figure 5 is a flow chart illustrating a process for assembling the damper assembly.

[0019] Figure 6 is a perspective view of securing the damper interface to the damper cap.

[0020] Figure 7 is a perspective view of securing the damper cap to the pressure tube of the damper assembly.

[0021] Figure 8 is a perspective view of securing the accumulator interface to the accumulator cap.

[0022] Figure 9 is a perspective view of securing the accumulator cap to the accumulator of the damper assembly.

[0023] Figure 10 is a perspective view of pressing the damper interface to the accumulator interface.

[0024] Figure 11 is a perspective view of securing the damper interface to the accumulator interface. DETAILED DESCRIPTION

[0025] With reference toFigure 1 and Figure 2 and wherein like numerals refer to like elements throughout the several views, a vehicle 20 having a plurality of damper assemblies 22 is shown. The vehicle 20 can be any suitable type of ground vehicle, such as a passenger or commercial automobile, such as a sedan, sports car, truck, sport utility vehicle, crossover vehicle, van, minivan, taxi, bus, etc.

[0026] The damper assemblies 22 are generally used in conjunction with an automotive suspension system or other suspension system to control the motion of the wheels of the vehicle 20 relative to the body of the vehicle 20. To control the motion, the damper assemblies 22 are generally connected between the sprung (body) mass and the unsprung (suspension / driveline) mass of the vehicle 20. Each damper assembly 22 can be coupled with a coil spring. Each damper assembly 22 is movable from a compressed position to an extended position, and vice versa. The distance between the ends of the damper assembly 22 in the compressed position is less than the distance between the ends of the damper assembly 22 in the extended position. A coil spring or the like can urge the damper assembly 22 toward the extended position. Forces applied to the wheels of the vehicle 20 (e.g., from bumps, potholes, etc.) can urge the damper assembly 22 toward the compressed position.

[0027] Each damper assembly 22 controls the motion of the corresponding wheel by restricting the flow of fluid into, out of, and / or between various chambers of the damper assembly 22 (e.g., into and out of and / or between the compression chamber and the rebound chamber). For example, as the damper assembly 22 moves toward the compressed position or the extended position, fluid movement is caused by the movement of the piston 24 within the pressure tube 26 of the damper assembly 22.

[0028] The pressure tube 26 is hollow and defines a first chamber 28 therein. The first chamber 28 can be filled with hydraulic fluid. The pressure tube 26 has a first outer surface 30 facing outward and away from the first chamber 28. The pressure tube 26 is elongated along a tube axis Al. The pressure tube can include one or more pressure tube openings 32 that allow fluid to flow into and / or out of the first chamber 28. The pressure tube openings 32 can be between the ends of the pressure tube 26, allowing radial (relative to the tube axis Al) fluid flow into and / or out of the first chamber 28.

[0029] Referring to Figure 2 and Figure 3The damper assembly 22 includes a damper interface 34. The damper interface 34 can be annular, i.e., ring shaped. The damper interface 34 can extend, for example, from a first proximal end 36 to a first distal end 38 opposite the first proximal end 36. The damper interface 34 can include a first tapered interface surface 40. The first tapered interface surface 40 can surround an interior of the damper interface 34. The first tapered interface surface 40 can define a diameter that is largest at the first distal end 38 and decreases toward the first proximal end 36. The damper interface 34 can include a first step 42. An outer diameter of the damper interface 34 on one side of the first step 42, e.g., near the first distal end 38, can be smaller than an outer diameter of the damper interface on an opposite side of the first step 42. The damper interface 34 can be secured to the first outer surface 30 of the pressure tube 26, e.g., at the pressure tube opening 32.

[0030] The damper assembly 22 can include a damper cap 44 connecting the pressure tube 26 to the damper interface 34. The damper cap 44 can be secured to the first outer surface 30 of the pressure tube 26 and to the damper interface 34, e.g., via welding. The damper cap 44 can be secured between the damper interface 34 and the first outer surface 30 of the pressure tube 26. The damper cap 44 can include a first top surface 46 and a first bottom surface 48 opposite the first top surface 46. The first top surface 46 can abut the damper interface 34, and the first bottom surface 48 can abut the pressure tube 26. The first bottom surface 48 can be shape complementary to the first outer surface 30 of the pressure tube 26. In other words, the first bottom surface 48 can be a mirror image of a profile of the first outer surface 30, e.g., such that the first bottom surface 48 of the damper cap 44 continuously abuts the first outer surface 30 of the pressure tube 26 around the pressure tube opening 32. The damper cap 44 can include a first central opening 50 extending, e.g., from the first top surface 46 to the first bottom surface 48. The damper cap 44 can surround the first central opening 50. The damper cap 44 can surround the damper interface 34. For example, the first proximal end of the damper interface can be disposed within the first central opening 50 of the damper cap 44, e.g., with the first step 42 of the damper interface 34 abutting the first top surface 46 and the first distal end 38 spaced apart from the pressure tube 26 and the damper cap 44.

[0031] Referring to Figure 2 and Figure 4The damper assembly 22 includes an accumulator tube 52 that provides a reservoir for hydraulic fluid of the damper assembly 22. The accumulator tube 52 is hollow and defines a second chamber 54 therein. The second chamber 54 can be filled with hydraulic fluid. The accumulator tube 52 has a second outer surface 56 that faces outward and away from the second chamber 54. The accumulator tube 52 is elongated along an accumulator axis A2. The accumulator tube 52 can include an accumulator opening 58 that allows fluid to flow into and / or out of the second chamber 54. The accumulator opening 58 can be between the ends of the accumulator tube 52, allowing radial (relative to the accumulator axis A2) fluid flow into and / or out of the second chamber 54. The accumulator tube 52 can include a floating piston therein that separates the second chamber 54 from a gas chamber on an opposite side of the floating piston within the accumulator tube 52. The floating piston is axially movable within the second chamber 54, for example to change the volume of the second chamber 54 according to a volume of fluid in the second chamber 54.

[0032] The damper assembly 22 includes an accumulator interface 60. The accumulator interface 60 can be annular, i.e., ring-shaped. The accumulator interface 60 can extend, for example, from a second proximal end 62 to a second distal end 64 opposite the second proximal end 62. The accumulator interface 60 can include a second tapered interface surface 66. The second tapered interface surface 66 can surround an exterior of the accumulator interface 60. The second tapered interface surface 66 can define a diameter that is smallest at the second distal end 64 and increases toward the second proximal end 62. The accumulator interface 60 can include a second step 68. An outer diameter of the accumulator interface 60 on one side of the second step 68 (e.g., near the second distal end 64) can be smaller than an outer diameter of the accumulator interface on an opposite side of the second step 68. The accumulator interface 60 can be fixed to the second outer surface 56 of the accumulator tube 52, for example at the accumulator opening 58.

[0033] Damper assembly 22 can include an accumulator cap 70 connecting accumulator tube 52 to accumulator interface 60. Accumulator cap 70 can be secured to second outer surface 56 of accumulator tube 52 and to accumulator interface 60, for example via welding. Accumulator cap 70 can be secured between accumulator interface 60 and second outer surface 56 of accumulator tube 52. Accumulator cap 70 can include a second top surface 72 and a second bottom surface 74 opposite second top surface 72. Second top surface 72 can abut accumulator interface 60, and second bottom surface 74 can abut accumulator tube 52. Second bottom surface 74 can be shape complementary to second outer surface 56 of accumulator tube 52. In other words, second bottom surface 74 can be a mirror image of the profile of second outer surface 56, for example such that second bottom surface 74 of accumulator cap 70 continuously abuts second outer surface 56 of accumulator tube 52 around accumulator opening 58. Accumulator cap 70 can include a second central opening 76, for example extending from second top surface 72 to second bottom surface 74. Accumulator cap 70 can surround second central opening 76. Accumulator cap 70 can surround accumulator interface 60. For example, second proximal end 62 of accumulator interface 60 can be disposed within second central opening 76 of accumulator cap 70, for example with second step 68 of accumulator interface 60 abutting second top surface 72 and second distal end 64 spaced apart from accumulator tube 52 and accumulator cap 70.

[0034] Damper interface 34 and accumulator interface 60 collectively enable the connection of pressure tube 26 and accumulator tube 52. Second chamber 54 and first chamber 28 of pressure tube 26 are in fluid communication via damper interface 34 and accumulator interface 60. In other words, fluid can flow from pressure tube 26 to accumulator tube 52 (or vice versa) through damper interface 34 and accumulator interface 60. Damper interface 34 can surround accumulator interface 60. For example, second distal end 64 of accumulator interface 60 can be disposed within first distal end 38 of damper interface 34. First tapered interface surface 40 of damper interface 34 can abut second tapered interface surface 66 of accumulator interface 60. Accumulator interface 60 can be pressure fit to damper interface 34. For example, a normal force between first tapered interface surface 40 and second tapered interface surface 66 can maintain the orientation and position of pressure tube 26 relative to accumulator tube 52. The pressure fit can include an interference fit between damper interface 34 and accumulator interface 60. For example, a diameter of first tapered interface surface 40 can be slightly smaller than a diameter of second tapered interface surface 66 prior to insertion of accumulator interface 60 into damper interface 34 such that insertion of accumulator interface 60 into damper interface 34 deforms first tapered interface surface 40 and / or second tapered interface surface 66. Accumulator interface 60 can be secured (e.g., welded) to damper interface 34.

[0035] Reference Figure 5, a flowchart is shown that illustrates a process 500 for securing an accumulator of a damper assembly 22 to a pressure tube 26 of the damper assembly 22. The process 500 begins at step 510, where a damper interface 34 is secured to a first outer surface 30 of the pressure tube 26. Securing the damper interface 34 to the first outer surface 30 of the pressure tube 26 can include securing the damper interface to a damper cap 44 and securing the damper cap 44 to the first outer surface 30 of the pressure tube 26. The damper cap 44 can be secured to the damper interface prior to the damper cap 44 being secured to the pressure tube 26.

[0036] The damper cap 44 can be secured to the damper interface 34 by inserting the first proximal end 36 into a first central opening 50 of the damper cap 44, for example from a first top surface 46 and up to a first step 42 abutting the first top surface 46. The damper cap 44 can then be secured, for example welded, to the damper interface 34. For example, as shown in Figure 6 the first distal end 38 can be welded to the damper cap 44 at the first bottom surface 48 and around a perimeter of the first central opening 50 and the first distal end 38 using a laser L. Next, the damper cap 44 can be secured, for example welded, to the first outer surface 30 of the pressure tube 26. For example, as shown in Figure 7 the damper cap 44 can be welded to the damper cap 44 at the first bottom surface 48 and around a perimeter of the first central opening 50 and the first distal end 38 using a laser L. Next, the damper cap 44 can be secured, for example welded, to the first outer surface 30 of the pressure tube 26. For example, as shown in

[0037] At step 520 of the process 500, an accumulator interface 60 is secured to a second outer surface 56 of the accumulator tube 52. Securing the accumulator interface 60 to the second outer surface 56 of the accumulator tube 52 can include securing the accumulator interface 60 to an accumulator cap 70 and securing the accumulator cap 70 to the second outer surface 56 of the accumulator tube 52. The accumulator cap 70 can be secured to the accumulator interface prior to the accumulator cap 70 being secured to the accumulator tube 52.

[0038] The accumulator cap 70 can be secured to the accumulator interface 60 by inserting the second proximal end 62 into a second central opening 76 of the accumulator cap 70, for example from a second top surface 72 and up to a second step 68 abutting the second top surface 72. The accumulator cap 70 can then be secured, for example welded, to the accumulator interface 60. For example, as shown in Figure 8 the second distal end 64 can be welded to the accumulator cap 70 at the second bottom surface 74 and around a perimeter of the second central opening 76 and the second distal end 64 using a laser L. Next, the accumulator cap 70 can be secured, for example welded, to the second outer surface 56 of the accumulator tube 52. For example, as shown in Figure 9 the second distal end 64 can be welded to the accumulator cap 70 at the second bottom surface 74 and around a perimeter of the second central opening 76 and the second distal end 64 using a laser L. Next, the accumulator cap 70 can be secured, for example welded, to the second outer surface 56 of the accumulator tube 52. For example, as shown in

[0039] At step 530, after securing the damper interface 34 to the pressure tube 26 and securing the accumulator interface 60 to the accumulator tube 52, the pressure tube 26 is secured to the accumulator tube 52. The pressure tube 26 can be secured to the accumulator tube 52 by press-fitting the damper interface 34 to the accumulator interface 60. For example, as shown in FIG. 5, the second distal end 64 of the accumulator interface 60 can be inserted into the first distal end 38 of the damper assembly 22. Press-fitting the damper interface 34 to the accumulator interface 60 can include pressing the first tapered interface surface 40 and the second tapered interface into abutment. In the case of an interference fit, sufficient force can be applied to the damper interface 34 and the accumulator interface 60 to slightly deform the first tapered interface surface 40 and / or the second tapered interface. After press-fitting the damper interface 34 to the accumulator interface 60, the damper interface 34 can be secured (e.g., welded) to the accumulator interface 60. For example, as shown in FIG. 6, a laser L can be used to weld the damper interface 34 to the accumulator interface 60 around the periphery of the damper interface 34 and the accumulator interface 60. The press-fit can provide sufficient securing to maintain the position of the pressure tube 26 relative to the accumulator tube 52 while welding the damper interface 34 to the accumulator interface 60, e.g., without the need for clamps or other securing devices to support the accumulator tube 52 relative to the pressure tube 26. Figure 10 Figure 11

[0040] In the drawings, like reference numerals refer to like elements throughout. Additionally, one or more of these elements can be altered. As to the media, processes, systems, methods, etc. described herein, it should be understood that, although the steps of such processes, etc. have been described as occurring according to a certain ordered sequence, such processes could be practiced with the described steps performed in an order other than the order described herein. It further should be understood that certain steps could be performed simultaneously, that other steps could be added, or that described steps could be modified, eliminated, or rearranged. In other words, the descriptions herein of processes is for illustration only and should not be construed to limit the claimed disclosure.

[0041] The disclosure has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the present disclosure are possible in light of the above teachings, and the disclosure can be practiced otherwise than as specifically described.​​

Claims

1. A method for assembling a damper assembly, the method comprising: securing a damper interface to an outer surface of a pressure tube; securing an accumulator interface to an outer surface of an accumulator tube; and then, after securing the damper interface to the pressure tube and securing the accumulator interface to the accumulator tube, securing the pressure tube to the accumulator tube by press-fitting the damper interface to the accumulator interface.

2. The method of claim 1, further comprising welding the damper interface to the accumulator interface after press-fitting the damper interface on the accumulator interface.

3. The method of claim 2, wherein the press-fit provides sufficient securing to maintain the position of the pressure tube relative to the accumulator tube when welding the damper interface to the accumulator interface.

4. The method of claim 2, wherein welding the damper interface to the accumulator interface comprises laser welding.

5. The method of claim 1, wherein the damper interface and the accumulator interface each comprise a tapered interface surface, and press-fitting the damper interface on the accumulator interface comprises pressing the tapered interface surfaces into abutment.

6. The method of claim 1, wherein the press-fit comprises an interference fit between the damper interface and the accumulator interface.

7. The method of claim 1, wherein securing the damper interface to the outer surface of the pressure tube comprises securing a damper cap to the damper interface and the outer surface of the pressure tube.

8. The method of claim 7, wherein securing the damper cap to the damper interface precedes securing the damper cap to the pressure tube.

9. The method of claim 8, wherein securing the damper cap to the outer surface of the pressure tube comprises welding the damper cap to the outer surface of the pressure tube.

10. The method of claim 9, wherein securing the damper cap to the damper interface comprises welding the damper cap to the damper interface.

11. A damper assembly, the damper assembly comprising: an elongate pressure tube having a first outer surface; a damper interface secured to the first outer surface; an accumulator having a second outer surface; and an accumulator interface secured to the second outer surface, the accumulator interface press-fitted with the damper interface, wherein the press-fit comprises an interference fit between the damper interface and the accumulator interface.

12. The damper assembly of claim 11, wherein the damper interface comprises a first tapered interface surface, and the accumulator interface comprises a second tapered interface surface that abuts the first tapered interface surface. ​ ​ 13. The damper assembly of claim 11, further comprising a damper cap secured to the damper interface and the first outer surface of the pressure tube, the damper cap positioned between the damper interface and the first outer surface of the pressure tube.

14. The damper assembly of claim 11, wherein the pressure tube defines a first chamber and the accumulator defines a second chamber, and the first chamber and the second chamber are in fluid communication via the accumulator interface and the damper interface.

15. The damper assembly of claim 11, wherein the accumulator interface is welded to the damper interface.

16. The damper assembly of claim 11, wherein the damper interface surrounds the accumulator interface.

17. A damper assembly, comprising: an elongated pressure tube having a first outer surface; a damper interface secured to the first outer surface; an accumulator having a second outer surface; an accumulator interface secured to the second outer surface, the accumulator interface pressure fit with the damper interface; and a damper cap secured to the damper interface and the first outer surface of the pressure tube, the damper cap positioned between the damper interface and the first outer surface of the pressure tube.

18. The damper assembly of claim 17, wherein the damper cap surrounds the damper interface.

19. The damper assembly of claim 17, wherein the damper cap includes a surface complementary to the first outer surface of the pressure tube.

20. The damper assembly of claim 17, wherein the damper cap is welded to the damper interface between the damper cap and the pressure tube. ​

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