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. 26, 1991
Filed:
Sep. 20, 1989
Klaus Metzner, Friedrichsdorf, DE;
Fresenius, AG, Bad Homburg, DE;
Abstract
In a measuring device for determination of the activity or the concentration of ions in solution comprising a flow channel (24) having a reference electrode and at least one measuring electrode, said flow channel having a first end (22) and a second end (23); a first line (18) connecting said first end of said flow channel to at least one calibrating liquid container (1,2,3) through first valve means (5,6,7); a first pumping means (14A) interposed in said first line (18) between said first valve means (5,6,7) and said first end (22) of said flow channel (24); a discharge line (19) connected to said first line adjacent said first end (22) of said flow channel (24), said discharge line having second pumping means (14B); a sample feed line (25) connected to said second end (23) of said flow channel for providing a sample to said flow channel; first and second sensors (10,11) arranged in said first and second ends of said flow channel, respectively, for detecting the flowing fronts of liquids, said sensors being capable of discriminating between the presence and absence of liquids and control means coupled to said sensors, pumping means, and valve means for controlling said pumping means and valve means, the improvement comprising a connection line (21) branching off from said exit line (19) of said second pump (14B), said connection line exiting into said flow channel (24) in the vicinity of said first exit (23), said connecting line (21), being provided with a first valve (9) and in said exit line (19), between the juncture of said lines (18) and 19 at mixing point 27 and the point of connection of connection line (21) to said exit line (19), a second valve (8) being provided.