SOLID-ELECTROLYTE OXYGEN CONCENTRATION DETECTOR AND METHOD OF MAKING THE DETECTOR Russian patent published in 2007 - IPC G01N27/406 

FIELD: measuring technique.

SUBSTANCE: method and detector can be used in metallurgy, power engineering, and chemical industry for measuring activity of oxygen in different media. Solid-electrolyte oxygen concentration detector has ceramic sensitive element placed hermetically inside case, comparison electrode and central electrode, both displaced inside cavity of ceramic sensitive element. Ceramic sensitive element is completely made of solid electrolyte in form of conjugated cylindrical element and part of sphere. External cylindrical part of ceramic sensitive element is connected with internal side surface of case by means of connecting material. Detector is additionally provided with plug made of metal oxide. Plug has opening and it overlaps cross-section of cavity of ceramic sensitive element. Comparison electrode is disposed in cavity formed by internal surface of ceramic sensitive element and surface of plug. Comparison electrode occupies at least part of cavity which part is turned to part of sphere. Free end of central electrode is withdrawn into space of comparison electrode through opening in plug. Electrical contact is provided between comparison electrode and lower part of central electrode. At least part of sphere of ceramic sensitive element protrudes out of case. Material of case, of ceramic sensitive element and of connecting material have similar temperature expansion coefficient. The materials have to be chemically resistant in relation to working medium. Bushing is soldered to internal part free part of case. Top part of central electrode protrudes out of bushing. Ring-shaped cavity between bushing and top part of central electrode is filled with dielectric material providing air-tightness of internal cavity of detector. Detector shows excellent operation under cyclical thermal shocks and at temperatures higher than 500C.

EFFECT: prolonged service life; higher reliability of operation.

23 cl, 1 dwg