Construction machine

摘要

A regeneration device that performs regeneration treatment of a particulate matter removing filter estimates a trapping amount of particulate matter trapped in the filter by two systems. Specifically, there are provided an estimating unit that estimates a first estimated trapping amount based upon a rotational speed of an engine and a fuel injection quantity and an estimating unit that estimates a second estimated trapping amount based upon a differential pressure across the particulate matter removing filter. The regeneration device determines whether or not the regeneration treatment is executed based upon whether or not at least one of the two estimated trapping amount is equal to or more than a preset trapping amount threshold value. Further, the regeneration device determines that there is a malfunction in the regeneration device in a case where the second estimated trapping amount is larger than the first estimated trapping amount.

主权项

1. A construction machine comprising:
an automotive vehicle body; an engine that is mounted on the vehicle body; an exhaust gas purifying device that is provided in an exhaust side of the engine and includes a filter for trapping particulate matter in an exhaust gas discharged from the engine; and a regeneration device that includes a microcomputer and memory, where the memory stores instructions that, when executed by the microcomputer, cause the microcomputer to perform a regeneration treatment that burns the particulate matter trapped in the filter in the exhaust gas purifying device, wherein the memory further stores instructions that, when executed by the microcomputer, cause the microcomputer to execute:
a first trapping amount estimating unit to estimate a first trapping amount (Q1) of particulate matter trapped in the filter based on at least a rotational speed of the engine and a fuel injection quantity,a second trapping amount estimating unit to estimate a second trapping amount (Q2) of particulate matter trapped in the filter based upon a differential pressure (ΔP=P1−P2) that is at least a difference between a pressure (P1) at an inlet side of the filter and a pressure (P2) at an outlet side thereof,a regeneration determining unit to determine that the regeneration treatment is to be performed when at least one of the first trapping amount (Q1) and the second trapping amount (Q2) is greater than or equal to a preset trapping amount threshold value (Qs), and a malfunction determining unit to determine that there is a malfunction in the regeneration device when the second trapping amount (Q2) is greater than the first trapping amount (Q1), a difference (ΔQ=Q2−Q1) between the first trapping amount (Q1) and the second trapping amount (Q2) is equal to or more than a preset predetermined value (ΔQs), and a continuous time (T) in a state where the difference (ΔQ=Q2−Q1) is equal to or more than the predetermined value (ΔQs) is equal to or more than a preset predetermined time (Ts).