FIELD: engines and pumps.
SUBSTANCE: invention relates to the purification of internal combustion engine exhaust gases. At the beginning of the calibration phase, the exhaust gas in the measurement space is displaced by filling measurement space (6) with the calibration gas, and at the end of the calibration phase the exhaust gas is diffused and/or introduced into the measurement space. Measurement space (6) is located in gas duct (5) of internal combustion engine (1) and consists of two perforated cylinders (20, 21) concentrically arranged into each other. At least one of the cylinders is rotatable about its longitudinal axis, so that both cylinders (20, 21) form a shielding device with a variable shielding action. Cylinders (20, 21) have, as perforations, at least two holes (22, 23) in the walls of the cylinders, disposed in particular with a displacement of 180°. They can be brought into a non-axial position or a co-axial position to open measurement space (6) for inflowing exhaust gas.
EFFECT: method and apparatus for calibrating an exhaust gas sensor are provided.
14 cl, 6 dwg
