Patent · US Expired

Piston rod for a vibration damper with amplitude-dependent damping force

US7228785B2 · kind B2 · utility

6Cited by

3References

8Claims

0Family size

Assignee

ZF FRIEDRICHSHAFEN AG · DE

Inventors

Ralf Wilhelm · Bad Wildbad, DE
Wolfgang Breun · Bitburg, DE
Klaus Sauer · Wiesloch, DE
Ludwig Eberlein · Sulzthal, DE

Key dates

Filing date	Aug 18, 2005
Grant date	Jun 12, 2007
Priority date	—
Expiry date	Aug 18, 2025

Classification

Technology area (CPC F)Mechanical Engineering; Lighting; Heating
CPC primaryF16F9/3221
WIPO fieldMechanical elements
WIPO sectorMechanical engineering

Abstract

A piston rod has a hollow section with an open end, a housing, and a fastening connection for a piston. The housing includes a cap welded to the open end, a tubular intermediate piece welded to the cap, and a bottom part attached to the fastening connection. The cap has a shoulder received in the intermediate piece to form an annular space which functions as a labyrinth seal to receive any weld spatters formed during the friction welding process. The outside surface of the piston rod is machined to final dimensions and surface coated following welding.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.