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:
Feb. 11, 2014
Filed:
Sep. 04, 2009
Ludger Alfes, Dorsten, DE;
Dirk Grieshaber, Wesel, DE;
Ludger Alfes, Dorsten, DE;
Dirk Grieshaber, Wesel, DE;
Siemens Aktiengesellschaft, München, DE;
Abstract
A shaft seal for sealing a gap between a shaft and a casing is provided. The shaft seal includes a plurality of sealing modules, at least one fluid supply and one fluid drain, and a first main seal on which a major partial pressure difference occurs. Conventional shaft seals of the above type require significant amounts of additional barrier fluid in regular intervals to ensure suitable pressure gradients. In the presently proposed shaft seal, the first main seal is designed as a radial double seal which is defined by two gas seals having respective rotating sealing surfaces and stationary sealing surfaces, the pair of sealing surfaces being opposite each other in a respective sealing plane. The sealing planes extend in a substantially radial manner relative to the shaft.