| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a secondary air supply device allowing the malfunction of structural components to be accurately determined and to detect an operating failure. <P>SOLUTION: The secondary air supply device is provided for supplying air to the upstream side of an exhaust emission control device in an engine exhaust pipe so that burnable materials in exhaust gas are secondarily burnt to purify the exhaust gas. It finds pressure behavior patterns (patterns 1-4) from a time average value for a pressure value and a pressure fluctuation value detected by a pressure sensor arranged between an air pump and an on-off valve and determines the operating conditions of the air pump and the on-off valve on the basis of variations of the pressure behavior patterns during controlling the supply and stop of secondary air. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
