Shock absorber for a motor vehicle

• US 20050133319A1
• Filed: 12/16/2004
• Published: 06/23/2005
• Est. Priority Date: 12/20/2003
• Status: Abandoned Application

• Current Assignee: Daimler AG (Mercedes-Benz Group AG)
• Original Assignee: Daimler AG (Mercedes-Benz Group AG)
• Inventors: Wilhelm, Ralf
• Application Number:
  US11/014,470
• Publication Number:
  US 20050133319A1
• Time in Patent Office: Days
• US Class Current: 188/281
• CPC Class Codes: F16F 9/5126 Piston, or piston-like valve elements F16F9/504 takes precedence

Abstract

In a shock absorber for a motor vehicle for damping the relative movement between a vehicle wheel and a vehicle body, comprising a damper housing filled with an operating medium and a piston rod with a piston disposed in the damper housing so as to divide the interior of the damper housing into two operating chambers and forming a first damper element, a second damper element is disposed in the piston rod and is in communication with the two operating chambers by way of bypass bores extending through the piston rod.

Claims

1. A shock absorber for a motor vehicle for damping the relative movement between a vehicle wheel and a vehicle body, comprising:

a damper housing (1) filled with an operating medium, a piston (3) disposed in said damper housing (1) and dividing the damper housing interior into two operating chambers (7, 8), a piston rod (2) extending into the damper housing (1) and being connected to the piston (3), which forms in the damper housing (1) a first damper element, and a second damper element (24) disposed in the piston rod (2) and being in communication with the two operating chambers (7, 8) by way of bypass bores (15, 16) extending in the piston rod (2).

2. A shock absorber according to claim 1, wherein the piston rod (2) comprises a first piston rod section (9) and a second piston rod section (10) joined with the first piston rod section (3).

3. A shock absorber according to claim 2, wherein the second piston rod section (10) includes a blind end bore (11) in which the second damper element (24) is disposed.

4. A shock absorber according to claim 2, wherein the first piston rod section (9) and the second piston rod section (10) are preassembled by a press fit connection (18).

5. A shock absorber according to claim 2, wherein the first and the second piston rod sections (9, 10) are welded together.

6. A shock absorber according to claim 1, wherein the second damper element (24) includes a slide member (12).

7. A shock absorber according to claim 6, wherein the slide member (12) includes seal areas (22) for blocking the bypass bores (15, 16).

8. A shock absorber according to claim 7, wherein the seal areas (22) the cone-shaped ends (22) of the slide member (12) and the bypass bores (15, 16) are arranged adjacent the opposite ends of the slide member (12), the cone-shaped ends (22) of the slide member (12) extending into the bypass bores (15, 16) for centering the slide member (12) in the bypass bore (15, 16).

9. A shock absorber according to claim 7, wherein the seal areas (22) of the slide member (12) are provided with layers of an elastomer material for improving the sealing quality of the seal areas.

10. A shock absorber according to claim 6, wherein one of said bypass bores (16) extends radially from said blind end bore (11) and the slide member 12 includes a guide structure with control edges for closing and opening the bypass bore (16).

11. A shock absorber according to claim 10, wherein the guide structure of the slide member 12 includes first and second axially spaced guide rims (28, 29).

12. A shock absorber according to claim 10, wherein the slide member (12) includes an axial center bore (27) and one of the guide rims (29) includes axial bores (30, 32) for accommodating operating medium flow therethrough.

13. A shock absorber according to claim 6, wherein springs (13, 14) are arranged at opposite ends of the slide member (12) resiliently engaging the slide member 12 therebetween.

14. A shock absorber according to claim 13, wherein the springs (13, 14) disposed at opposite ends of the slide member (12) have different spring characteristics.

15. A shock absorber according to claim 13, wherein said springs (13, 14) have progressive spring characteristics.

16. A shock absorber according to claim 13, wherein said springs (13, 14) have temperature dependent spring characteristics.