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:
Nov. 13, 2007
Filed:
Jul. 29, 2005
Serge Nassif, Mundolsheim, FR;
Serge Nassif, Mundolsheim, FR;
Dr. Ing. h.c.F. Porsche Aktiengesellschaft, Stuttgart, DE;
Abstract
A hydraulic linear drive, in particular for a hydraulic transmission actuator, has a piston/cylinder unit in which an adjusting piston is situated so that it is longitudinally displaceable in a cylinder housing and divides a cylinder space into at least two pressure spaces. The pressure spaces can be acted upon by hydraulic oil via controllable pressure supply through hydraulic lines. A sealing ring is situated on the adjusting piston or on the cylinder housing for sealing, the two pressure spaces with respect to one another. The sealing ring is accommodated in a ring groove on the cylinder housing so as to seal with its inside against the adjusting piston. A sealing pressure supply system communicates hydraulic oil to the outside of the sealing ring so as to control the sealing pressure of the sealing ring on the piston surface.