FUEL INJECTION CONTROL DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a fuel injection control device, preventing generation of white smoke in controlling an exhaust temperature rise. SOLUTION: This fuel injection control device includes: an after treatment device 30 for purifying exhaust emission by the action of a catalyst; an exhaust temperature detecting means 34 for detecting exhaust temperature; and a control means 12 for controlling the fuel injection quantity and the fuel injection timing. The control means 12 performs the exhaust temperature rise control using post-injection when the exhaust temperature detected by the exhaust temperature detecting means 34 is lower than the active temperature of the catalyst of the after treatment device 30. The control means 12 determines the target injection quantity of post-injection according to a difference between the target exhaust temperature and the actual exhaust temperature detected by the exhaust temperature detecting means 34 and determines the upper limit value of injection quantity of post-injection according to the actual exhaust temperature detected by the exhaust temperature detecting means 34 in performing the exhaust temperature rise control. The control means controls the injection quantity of the actual post-injection to reach the upper limit value when the target injection quantity is above the upper limit value. Further it controls the injection quantity of the actual post-injection to reach the target injection quantity when the target injection quantity is smaller than the upper limit value. COPYRIGHT: (C)2004,JPO&NCIPI