(19)
(11) EP 2 495 420 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
12.09.2012 Bulletin 2012/37

(43) Date of publication A2:
05.09.2012 Bulletin 2012/36

(21) Application number: 12150080.5

(22) Date of filing: 03.01.2012
(51) International Patent Classification (IPC): 
F02D 41/02(2006.01)
E02F 9/08(2006.01)
 F01N 9/00(2006.01)
(84) Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated Extension States:
BA ME

(30) Priority: 13.01.2011 JP 2011004960

(71) Applicant: Hitachi Construction Machinery Co., Ltd.
Bunkyo-ku Tokyo 112-0004 (JP)

(72) Inventors:
  • Kamiya, Shouhei
    Tsuchiura-shi, Ibaraki 300-0013 (JP)
  • Arai, Yasushi
    Tsuchiura-shi, Ibaraki 300-0013 (JP)

(74) Representative: Jansen, Cornelis Marinus et al
VEREENIGDE Johan de Wittlaan 7
2517 JR Den Haag
2517 JR Den Haag (NL)

   


(54) Exhaust gas purification system for working machine


(57) Disclosed is an exhaust gas purification system for a working machine. The system is provided with a filter (20) for capturing particulate matter contained in exhaust gas from an engine, a differential pressure sensor (21) for detecting a differential pressure between an exhaust upstream side and an exhaust downstream side of the filter, and a controller (22) having a regeneration determination unit for determining whether or not a time, at which forced regeneration is needed, has been reached. The controller includes one that has a variation determination unit for determining whether or not a state quantity relevant to an operation of the engine, for example, an engine speed has varied abruptly and that, when the state quantity is determined to have abruptly varied, performs processing to invalidate the determination by the regeneration determination unit during a predetermined time in which an effect of the state quantity is considered to diminish.







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Search report