JPH01113119U

JPH01113119U -

Info

Publication number: JPH01113119U
Application number: JP805888U
Authority: JP
Priority date: 1988-01-25
Filing date: 1988-01-25
Publication date: 1989-07-31

Description

[Brief explanation of the drawing]

第１図は本考案の一実施例を示す構成図である
。第２図はエンジン回転数と排圧との関係を示す
線図である。第３図はエンジン回転数と排圧との
関係を示す他の線図である。第４図乃至第９図は
それぞれ第１図に示す装置の作用を説明するため
のフローチヤートである。主要な部分の符号の説明、１０……メイン排気
通路、１２……メインフイルタ、１６……サブ排
気通路、１８……サブフイルタ、２０……メイン
リターン通路、２２……サブリターン通路、２４
……第１切換弁、２６……第２切換弁、２８……
第３切換弁、３０……第４切換弁、３４……コン
トローラ、３６……エンジン回転数センサ、３８
……エンジン負荷センサ、４０，４２……排気圧
力センサ。 FIG. 1 is a block diagram showing an embodiment of the present invention. FIG. 2 is a diagram showing the relationship between engine speed and exhaust pressure. FIG. 3 is another diagram showing the relationship between engine speed and exhaust pressure. 4 to 9 are flowcharts for explaining the operation of the apparatus shown in FIG. 1, respectively. Explanation of symbols of main parts, 10...Main exhaust passage, 12...Main filter, 16...Sub exhaust passage, 18...Sub filter, 20...Main return passage, 22...Sub return passage, 24
...First switching valve, 26...Second switching valve, 28...
Third switching valve, 30...Fourth switching valve, 34...Controller, 36...Engine speed sensor, 38
...Engine load sensor, 40, 42...Exhaust pressure sensor.

Claims

[Scope of utility model registration request]

A main exhaust passage that guides exhaust gas to the muffler, a main filter that collects particulate matter in the main exhaust passage, a sub-exhaust passage that guides exhaust gas to the muffler bypassing the main filter, and a particulate matter in the sub-exhaust passage. A sub-filter that collects curate, a main return passage that guides exhaust gas discharged from the main filter to the inlet side of the sub-filter, a sub-return passage that guides exhaust gas discharged from the sub-filter to the inlet side of the main filter, and a main exhaust passage. A first switching valve is provided at the joint between the main exhaust passage and the main return passage, and is provided at the joint between the main exhaust passage and the main return passage, and closes one of these passages and opens the other. a second switching valve that opens the other; a third switching valve that is provided at the joint between the sub-exhaust passage and the main return passage; and a third switching valve that closes one of these passages and opens the other; and the connection between the sub-exhaust passage and the sub-return passage. a fourth switching valve that closes one of these passages and opens the other; an exhaust pressure sensor that detects each exhaust pressure in the main exhaust passage and the sub-exhaust passage; and an engine operating state that detects the operating state of the engine. a comparison means for capturing the outputs of the exhaust pressure sensor and the engine operating state sensor and comparing the reference exhaust pressure according to the output of the engine operating state sensor with the output of the exhaust pressure sensor; and an output of the exhaust pressure sensor from the comparing means. a switching valve that outputs a switching command to each switching valve for guiding exhaust gas discharged from one filter of the filter group to the inlet side of the other filter when a comparison result is obtained in which the exhaust pressure is equal to or lower than a reference exhaust pressure; An exhaust gas purification device for a diesel engine, characterized in that it has a control means.