| 摘要 |
PURPOSE:To eliminate mismeasurement of an oxygen pump type oxygen concn. detector, by installing a dust protection near the diffusion-resistant material of the oxygen concn. detector. CONSTITUTION:An oxygen concn. detector 3 made of a solid electrolyte 31 having oxygen ion conductivity, such as ZrO2-Y2O3 mixture, is installed in the part of a gas discharging pipe 2. A cover 31 made of a heat-resistant material is installed around the electrolyte 31 to prevent the electrodes 33 of the electrolytes 31 from exposure directly to a waste gas. Parts of the cover 34 are provided with orifices 39a, 39b as diffusion resistant materials. A dust protection 37 having orifices 39a, 39b are provided around this cover 34 to prevent particles of carbon, lead, etc. and the unburned component of fuel contained in the waste gas from reaching the orifices 35a, 35b, and also the cover 34 from being overcooled or overheated with the waste gaseous flow. |
