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. 25, 2019
Filed:
Apr. 22, 2014
Endress + Hauser Gmbh + Co. KG, Maulburg, DE;
Nils Ponath, Lorrach, DE;
Andreas Rossberg, Bad Sackingen, DE;
ENDRESS+HAUSER SE+CO.KG, Maulburg, DE;
Abstract
A pressure measurement cell, comprising: a ceramic measurement membrane and a ceramic counterpart. The measurement membrane is joined to the counterpart in a pressure-tight manner forming a pressure chamber between the measurement membrane and the counterpart by means of an active brazing solder. The pressure measurement cell furthermore has a solder stop layer on a surface of the measurement membrane and/or the counterpart, wherein the solder stop layer has a metal oxide or a reduced form of the metal oxide. The metal oxide has at least one oxidation stage, which, assuming an activity coefficient of R=1 at an inverse temperature of 8·10/K, has an oxygen coexistence decomposition pressure of not less than 1MPa (10bar) and not more than 1MPa (10bar) and which, assuming an activity coefficient of R, at an inverse temperature of 9·10/K has an oxygen coexistence decomposition pressure of not less than 1MPa (10bar) and not more than 1MPa (10bar). Suitable metal oxides are, for example, oxides of chromium, tungsten or titanium.