The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 23, 2010
Filed:
Mar. 06, 2006
Norbert Ackermann, Eitorf, DE;
Norbert Ackermann, Eitorf, DE;
ZF Friedrichshafen AG, Friedrichshafen, DE;
Abstract
A self-pumping hydropneumatic vibration damper with internal level control, especially for motor vehicles, has an oil-filled working cylinder under the pressure of at least one gas cushion. The working cylinder is divided into two working spaces by a working piston mounted on a piston rod. A piston pump, which is driven by the sprung movements of the vehicle and thus conveys damping oil from a low-pressure chamber into the working space connected to the high-pressure chamber. The pump cylinder of this piston pump is formed by the hollow piston rod, which connects the working space connected to the high-pressure chamber to the low-pressure chamber. An axially movable stepped pump piston is provided in the pump cylinder.