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AssigneeNgk Spark Plug Co., Ltd.
InventorsToshiki Sawada, Masaru Yamano, Kazuo Taguchi, Takao Kojima, Hiroyuki Ishiguro, Masahiko Yamada
Estimating the term…
Oxygen sensor for air-fuel ratio control is provided with a sensor element having an oxygen ion-conductive main body and electrodes on both sides thereof, and at least one porous protective layer covering the electrode on the exhaust gas side. The protective layer includes an oxygen storage component OSC without copresence of a noble metal catalyst. The protective layer is intermeshingly connected to the main body via spherical protrusions of the main body. Double-layered protective layer structure includes OSC noncontaining layer (optionally containing catalyst) and OSC containing layer, as inner and outer protective layer or vice versa. OSC containing layer is formed by impregnation with OSC-solution through immersing the respective porous protective layer, or by cosintering the OSC containing green coating layer. By impregnation 0.2-8 wt %, or by cosintering 0.2-30 wt %, of OSC metal element is containable. The outer protective layer is thinner and more porous than the inner protective layer. Any of the protective layers can be formed by flame spraying.
A method of producing an oxygen sensor for air-fuel ratio control comprising a sensor element having a main body and electrodes disposed on sides of the main body and a protective layer covering the electrode on the side of the sensor element assigned to be exposed to a gas to be measured for oxygen, the method comprising the steps of:
A method of producing an oxygen sensor for air-fuel ratio control comprising a sensor element having a main body and electrodes disposed on sides of the main body and protective layers on the side of the sensor element assigned to be exposed to a gas to be measured for oxygen, the method comprising the steps of:
A method of producing an oxygen sensor for air-fuel ratio control comprising a sensor element having a main body and electrodes disposed on sides of the main body and protective layers on the side of the sensor element assigned to be exposed to a gas to be measured for oxygen, the method comprising the steps of:
A method of producing an oxygen sensor for air-fuel ratio control comprising a sensor element having a main body and electrodes disposed on sides of the main body and protective layers on the side of the sensor element assigned to be exposed to a gas to be measured for oxygen, the method comprising the steps of:
Dependencies are inferred from the claim text.