Kubota Corporation

Masanori Fujiwara

Katsushi Inoue

Yasuo Fujii

Yuuki Ishii

Hiroaki Okano

Kenta Mitamura

Noriyoshi Eguchi

Tamotsu Kuno

Koichi Funaki

Yuki Yoshita

Kentaro Kita

Yongchol Lee

Tomohiro Ninomiya

Yasuo Fuji

There is provided an exhaust treatment device for a diesel engine capable of accurately estimating an amount of ash deposition. In the exhaust treatment device, an ash deposition estimation device estimates an amount of ash deposition on a DPF after ending of regenerating treatment for the DPF, based on data regarding differential pressure and exhaust flow rate stored in a memory device over a period immediately before the end of regeneration, the period ranging from the end point of regenerating treatment for the DPF to a point in time going back a predetermined duration. An electronic control device preferably makes an alarm device issue an alarm, upon arrival of an estimated value of ash deposition at a predetermined alarm request value.

Exhaust treatment device for diesel engine

An engine promoting DPF regeneration processing is provided. Catalyst activation processing and thereafter DPF regeneration processing are performed under control of a device. In the catalyst activation processing, a target temperature of exhaust at an exhaust exit of a catalyst is set to be in a first temperature region, and then the opening degree of an exhaust throttle device is controlled. In the DPF regeneration processing, the target temperature is set to be in a second temperature region. A target temperature of the exhaust at an exhaust inlet of a DPF is set to be in a third temperature region. The opening degree of the exhaust throttle device is controlled, and unburned fuel is supplied into the exhaust. The temperature regions are set to be successively higher, and a temperature difference between successive temperature regions is set to be successively lower.

Engine

There is provided an exhaust treatment device for a diesel engine that can prevent unnecessary alarm for ash deposition from being issued. In the exhaust treatment device, a timer measures integrated time of a state of non-regenerative operation which ranges from an end of DPF regeneration to a next time point where the differential pressure reaches a regeneration request value. A counter acquires the short interval count if the integrated time is a short interval shorter than a predetermined decision time. An alarm device issues an alarm if the consecutive short interval count reaches a predetermined plural necessary count for alarm. A short interval count having been already acquired is preferably reset to 0 if the integrated time of the state of non-regenerative operation is a long interval, not shorter than a predetermined decision time, before the short interval count reaches the predetermined necessary count for alarm.

The disclosed exhaust treatment device for a diesel engine can prevent heat damage to a DPF when regenerating said DPF. If a selection device (), which selects whether to allow or prohibit an automatic DPF regeneration process, is set to prohibit the automatic DPF regeneration process, a DPF regeneration control device () is made able to start a process to cancel execution of the automatic DPF regeneration process. If the selection device () is set to allow the automatic DPF regeneration process, the DPF regeneration control device () retracts the cancellation of the automatic DPF regeneration process, allowing execution of the previously-cancelled automatic DPF regeneration process to begin.

Exhaust treatment device for a diesel engine

An object of the present invention is to provide the exhaust treatment device of a diesel engine which is capable of prohibiting the execution of DPF regenerating processing in a situation in which the DPF regenerating processing is inappropriate. In order to achieve the object, DPF regenerating mode switch manipulation means () switches a DPF regenerating mode to a normal and acceleration coexistence regenerating mode () or an acceleration-sole regenerating mode (), and DPF regenerating selection manipulation means () switches a position to a normal regenerating permission position (), a normal regenerating cancel position (), or an acceleration regenerating execution position (). When the DPF regenerating mode is in the acceleration-sole regenerating mode (), the DPF regenerating control means prohibits normal regenerating processing by the DPF regenerating means irrespective of a position selected by the DPF regenerating selection manipulation means ().

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Sakai, Japan

Masanori Fujiwara