Gas sensor to detect the concentration of nitrous oxides in automotive exhaust gases maintains accuracy under a wide range of temperatures

摘要

A gas sensor to detect the concentration of nitrous oxides in automotive exhaust gases. A gas sensor (1, 1') has a gas chamber (15, 17) for a sample of the gas in question, and a second gas chamber (16) holding a sample of the reference gas. The concentration of the sample gas is detected by a sensor (3). Oxygen is pumped into or out of the sample gas chamber by a pump cell (2). An admission passage (100) has a fine perforation arranged on top of the oxygen pump cell, and discharges the test gas into the sample gas chamber. The upper surface of the oxygen pump cell (2) faces or is directed at the upper surface of the gas sensor. A porous diffusion resistance layer (10) is located on the upper surface of the oxygen pump cell, covering the admission passage (100).