Patent ID: 8033099

Claim:
An exhaust gas purifying system comprising: an additive agent injection valve, mounted on a passage wall of an exhaust gas passage through which exhaust gas as a target in purification passes, capable of injecting an additive agent into the exhaust gas passage; and a catalyst unit having catalyst, placed in a downstream side of the additive agent injection valve in the exhaust gas passage, capable of promoting an exhaust gas purifying reaction using at least the additive agent transported from the additive agent injection valve to the catalyst unit through the exhaust gas flow, wherein the additive agent injection valve comprises: a first spray injection part for injecting a first spray of the additive agent having a first traveling distance into the exhaust gas passage; and a second spray injection part placed at the upstream side of the exhaust gas flow in the exhaust gas passage when compared with the position of the first spray infection part, which injects a second spray of the additive agent having a second traveling distance, which is greater than the first traveling distance, in the exhaust gas passage.