Patent ID: 6355151
Filing Date: 2002-03-12
Classification: G01N

Abstract:
A gas sensor for measurement of oxygen and/or the air/fuel lambda ratio and hydrocarbons and/or carbon monoxide in a gas mixture, comprising at least one reference electrode representing a constant oxygen partial pressure, an oxygen ion-conducting solid electrolyte, and at least two measuring electrodes, the at least one reference electrode being mounted directly on the oxygen ion-conducting solid electrolyte and having electrical leads for connection and for take-away of at least two electrical measurement signals, each electrical signal corresponding to a different gaseous component of the gas mixture, wherein the oxygen ion-conducting solid electrolyte has a measurement gas side exposed to the gas mixture and a reference gas side separated from the gas mixture, wherein the at least one reference electrode is arranged on the reference gas side and the at least two measuring electrodes are arranged on the measurement gas side, wherein a single one of the at least one reference electrodes is operable with at least two of the measuring electrodes, the respective two measuring electrodes being spaced apart on the oxygen ion-conducting solid electrolyte, being covered with a porous diffusion layer and being exposed to the gas mixture, and wherein the porous diffusion layer has a different thickness over the respective two measuring electrodes and wherein the two measuring electrodes comprise the same catalytic activity.