EMISSION CONTROL DEVICE FOR DIESEL ENGINE

• Main Author: MINAMI TOSHITAKA
• Format: Patent
• Language: English
• Published: 23.06.2005
• Edition: 7
• Subjects: BLASTING; COMBUSTION ENGINES; CONTROLLING COMBUSTION ENGINES; ENGINE PLANTS IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNALCOMBUSTION ENGINES; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES ORENGINES IN GENERAL; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; LIGHTING; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; STEAM ENGINES; SUPPLYING COMBUSTION ENGINES IN GENERAL, WITH COMBUSTIBLEMIXTURES OR CONSTITUENTS THEREOF; TRANSPORTING; WEAPONS

PROBLEM TO BE SOLVED: To collect PM well even in an operation zone of low exhaust gas temperatures and simultaneously to reduce NOx which is noxious component in exhaust gas without giving ill effect to operability or the like. SOLUTION: A bypass passage is provided in an exhaust gas passage 7 of a diesel engine provided with continuous regeneration type DPF 12 and a second continuous regeneration type DPF 13 of small capacity is installed. PM is collected by the second continuous regeneration type DPF 13 in a low exhaust temperature zone. An exhaust gas introducing mechanism by exhaust valve lift and EGR device re-circulating exhaust gas through a cooler 200 are provided. Generation of NOx is suppressed by re-circulating cooled exhaust gas in the high temperature zone of the low exhaust gas temperature zone and cooled exhaust gas re-circulation is stopped for preventing degradation of combustion or the like in the low temperature zone of the low exhaust gas temperature zone. COPYRIGHT: (C)2005,JPO&NCIPI