ADDITIVE SUPPLY DEVICE FOR INTERNAL COMBUSTION ENGINES

摘要

An engine (1) is provided with an SCR catalyst (41) for purifying NOx, an urea injection valve (230) for adding urea water to the SCR catalyst (41), and a first NOx sensor (130) for detecting NOx emissions. A control device (80) totals the NOx emissions from the previous injection of urea water, and after the total value reaches a reference value or more, an addition process to inject urea water from the urea injection valve (230) is performed.