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:
Jan. 02, 1990
Filed:
Sep. 15, 1987
Arthur E Colvin, Jr, Mount Airy, MD (US);
Cerex Corporation, Gaithersburg, MD (US);
Abstract
Liquid chromatography apparatus including a hollow cylinder and a fixed end closure in which the effective useful length of the cylinder is varied through the use of a piston member that slides within the cylinder due to force exerted by a threaded shaft that is connected to a handle. Binding of the piston member in the cylinder is prevented by a ball joint that operatively connects the piston member to the threaded shaft and by a plurality of O-rings located on the piston member that contact the inner wall of the cylinder and tend to prevent tipping of the piston member. Even liquid distribution and filtering is obtained through a 0.5 micron porous sintered stainless steel liquid distribution disk. A smooth inclined surface in combination with an uninterrupted ring provide a trap for bubbles of gas located inside the cylinder. A composite porous segmented sintered liquid distribution disk is also presented that is particularly useful for large scale liquid chromatography as is the method of manufacturing the composite segmented disk.