Pressure detection mechanism for exhaust emission control device of internal combustion engine

摘要

A pressure detection mechanism for a catalyst (450) of an engine (1000), in which the catalyst (450) includes an upstream NSR catalyst (460) and a downstream DPNR catalyst (470) stored in a catalyst casing, which includes a DPNR front pressure detection pipe (462) connected to a space formed by the NSR catalyst (460), the DPNR catalyst (470) and the catalyst casing, a DPNR rear pressure detection pipe (472) downstream of the DPNR catalyst (470) connected to a space formed by the DPNR catalyst (470) and the catalyst casing, and a pressure difference transducer (490) connected to the DPNR front pressure detection pipe (462) and the DPNR rear pressure detection pipe (472).