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. 10, 2007
Filed:
Oct. 08, 2003
Applicants:
Eckard Bez, New Bern, NC (US);
Thorsten Burggraf, Runkel, DE;
Stefan Zabeschek, Asslar, DE;
Inventors:
Assignee:
Pfeiffer Vacuum GmbH, Asslar, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F04B 39/10 (2006.01);
U.S. Cl.
CPC ...
Abstract
A piston machine includes a cylindrical wall () defining a swept volume () and having a plurality of gas inlet openings (), and a piston () reciprocating in the swept volume (), and the piston head () of which is formed as a valve having a plurality of openings () provided in the piston head (), and a forcelocking device () for retaining the plurality of openings () in one of their open condition and closed condition.