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:
Jun. 12, 2012
Filed:
Dec. 09, 2008
Hermann Hochgraeber, Offenberg-Neuhausen, DE;
Gervin Ruegenberg, München, DE;
Hermann Hochgraeber, Offenberg-Neuhausen, DE;
Gervin Ruegenberg, München, DE;
Dionex Softron GmbH, Germering, DE;
Abstract
An autosampler for high-performance liquid chromatography (HPLC) with a high-pressure injection valve () having improved life, particularly in high pressure operation. The geometry of the valve components and the connections of the high-pressure injection valve are provided such that the switching processes do not take place in a deleterious direction. The grooves in rotor () and/or the port opening cross sections () in stator () and the rotational direction are selected such that fluid flows from grooves under high pressure in the direction of narrow, substantially pressure-free ports are avoided. This applies in particular to the switching process from INJECT to LOAD, since the sample loop contains a relatively large dead volume of compressed fluid. In addition, the valve can be controlled according to the invention in such a manner that an appropriate time is available for reducing harmful or undesired pressure differences.