Patent ID: 8875492

Claim:
An exhaust pipe injection control device comprising: a diesel particulate filter which is installed in an exhaust pipe of an engine and which collects particulate matter; an exhaust pipe injector which is installed upstream of the diesel particulate filter and which injects fuel into the exhaust pipe; a feed pump which supplies fuel to the exhaust pipe injector; a controller which sets, according to an engine rotation speed and an exhaust gas flow rate, a target injection amount that is injected in a single injection from the exhaust pipe injector; and an injection time map in which a fuel injection time of the exhaust pipe injector is set so that, with respect to the target injection amount and an exhaust pipe injection fuel pressure that is a pressure of fuel that acts on the exhaust pipe injector, fuel in the target injection amount is injected; wherein the controller performs injection from the exhaust pipe injector by referring to the injection time map based on the target injection amount and the exhaust pipe injection fuel pressure, wherein the fuel injection time of the injection time map is set longer when the target injection amount is greater, and is set shorter when the exhaust pipe injection fuel pressure is higher.