Exhaust purification system for working machine

Abstract

An exhaust purification system for a working machine reliably issues filter regeneration warnings to the operator, prompting manual regeneration, so that damage to the DPF device can be avoided. When a PM estimate becomes higher than a given value, a screen displays a warning message prompting manual regeneration. If the warning message fails to prompt the operator to perform manual regeneration and reference time t 1 has passed since the display of the warning message, a speaker outputs a first warning sound. When the operator notices the first warning sound and turns on a regeneration switch, regeneration control is started. If the operator fails to notice the first warning sound and reference time t 2 passes, the speaker instead outputs a second warning sound louder than the first warning sound. When the operator notices the second warning sound and turns on the regeneration switch, regeneration control is started.

1 . (canceled) 
     
     
         2 . (canceled) 
     
     
         3 . An exhaust purification system for working machine, the system comprising:
 a filler ( 32 ), located in an exhaust system of an engine ( 1 ), for capturing particulate matter contained in exhaust;   a regeneration device ( 33 ,  39 ) for burning off particulate matter accumulated on the filter to regenerate the filler;   a regeneration controller ( 42 ) for starting or stopping the operation of the regeneration device;   a regeneration switch ( 38 ) for instructing the regeneration controller to start regeneration; and   warning means ( 6   a ,  42   a ,  43 ) for prompting an operator to turn on the regeneration switch,   wherein the system further comprises status judging means ( 3 ,  8 ,  41   a ,  47 ) for judging the status of the working machine,   wherein the warning means includes a warning sound output function ( 6   c ) for outputting warning sounds and a warning sound altering function ( 41   b ) for altering the warning sounds after the amount of time during which the status judging means judges the working machine to be in operation has exceeded reference times since a first warning,   wherein in the event that the status judging means judges the working machine to be in operation, the status judging means further judges whether the working machine is in standby status or work-in-progress status, and   wherein the warning sound altering function sets different reference times depending on the standby status or the work-in-progress status.   
     
     
         4 . The exhaust purification system of  claim 3   wherein the working machine comprises:   an engine speed detector ( 3 );   a work-performing structure;   operating levers ( 28 ,  29 ) for controlling the operation of the work-performing structure;   a gate lock lever ( 7 ) movable between an unlock position that enables the operation of the operating levers and a lock position that disables the operation of the operating levers; and   a pilot pressure sensor ( 47 ) for detecting pilot pressures generated by the operating levers,   wherein the status judging means judges the working machine to be in the standby status in the event that the engine speed detector has detected a speed higher than a low idle speed and that the gate lock lever is in the lock position, and   wherein the status judging means judges the working machine to be in the work-in-progress status in the event that the engine speed detector has detected a speed higher than the low idle speed, that the gate lock lever is in the unlock position, and that the pilot pressure sensor has detected a pressure higher than a given value.   
     
     
         5 . The exhaust purification system of  claim 3   wherein the warning sound altering function alters at least either one of the following: the volume, tone, length, and repeat count of the warning sounds.   
     
     
         6 . (canceled)