Exhaust gas processing device for diesel engine

An exhaust gas processing device for a diesel engine, the device comprising:

• a DPF 1;
• a PM accumulation amount estimating section 2 for PM accumulated in the DPF 1;
• a DPF regeneration section 3;
• a DPF regeneration control section 4;
• a storage section 5;
• an accelerated regeneration requiring information notification section 6;
• an accelerated regeneration starting operation section 7;
• and
• an accelerated regeneration re-requirement notification section 41, wherein
• an accelerated regeneration requirement determination value J2, a normal regeneration starting determination value J3, and a normal regeneration prohibition and accelerated regeneration re-requirement determination value J4 higher than the determination values J2 and J3 are stored in the storage section 5,
• the DPF regeneration control section 4 compares a PM accumulation amount estimate obtained by the PM accumulation amount estimating section 2 with the plurality of determination values J2, J3, and J4, and the DPF regeneration control section 4 automatically starts normal regeneration processing by the DPF regeneration section 3 (S2) to increase a temperature of exhaust gas 11 to be passed through the DPF 1 when the PM accumulation amount estimate increases to the normal regeneration starting determination value J3,
• the DPF regeneration control section 4 starts notification of accelerated regeneration requiring information by the accelerated regeneration requiring information notification section 6 (S8) when the PM accumulation amount estimate is equal to or higher than the accelerated regeneration requirement determination value J2 as a result of determination for accelerated regeneration requirement after that,
• the DPF regeneration control section 4 switches the normal regeneration processing by the DPF regeneration section 3 to accelerated regeneration processing (S10) to increase the temperature of the exhaust gas 11 to be passed through the DPF 1 as in the normal regeneration processing to make regeneration speed of the DPF 1 higher than that in the normal regeneration processing when the accelerated regeneration starting operation section 7 carries out accelerated regeneration starting operation after the notification of the accelerated regeneration requiring information is started (S8),
• the DPF regeneration control section 4 continues the normal regeneration processing by the DPF regeneration section 3 (S11) when the accelerated regeneration starting operation section 7 does not carry out the accelerated regeneration starting operation after the notification of the accelerated regeneration requiring information is started (S8), and the DPF regeneration control section 4 prohibits the normal regeneration processing (S13) and the accelerated regeneration re-requirement notification section 41 starts notification of the accelerated regeneration re-requiring information (S14) when the PM accumulation amount estimate becomes equal to or higher than the normal regeneration prohibition and accelerated regeneration re-requirement determination value J4, and thereafter, the regeneration processing of the DPF 1 is not carried out unless the accelerated regeneration starting operation section 7 starts the accelerated regeneration starting operation (S16) to cause the DPF regeneration control section 4 to carry out the accelerated regeneration processing by the DPF regeneration section 3.