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:
Jul. 12, 2005
Filed:
Jan. 17, 2003
Karsten Mischker, Leonberg, DE;
Uwe Hammer, Hemmingen, DE;
Stefan Reimer, Markgroeningen, DE;
Ralph Engelberg, Ditzingen, DE;
Karsten Mischker, Leonberg, DE;
Uwe Hammer, Hemmingen, DE;
Stefan Reimer, Markgroeningen, DE;
Ralph Engelberg, Ditzingen, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A cylinder-piston drive, e.g., an hydraulically controlled actuator for actuating a gas-exchange valve of an internal combustion engine, has an operating piston that is displaceable inside a cylinder and delimits pressure chambers by piston sides facing away from one another. The operating piston has a multipart design and is made up of at least two partial pistons that are placed inside one another, are displaceable relative to each other and strike against one another at stop faces. One pressure chamber is delimited by all, and the other pressure chamber is delimited by only a part, of the partial pistons and the sliding paths of the partial pistons not delimiting the other pressure chamber may be reduced compared to the overall sliding path of the operating piston. At least one stop face, arranged on the cylinder, may be provided against which a stop face of one of the partial pistons strikes after traveling the reduced sliding path. At least some of the stop faces associated with each other may be designed as conical surfaces that in each case form a conical seat when struck. In this manner, the leakage volume flow may be reduced by the operating piston.