Patent · US Expired

Exhaust gas-purifying system for internal combustion engines

US5467594A · kind A · utility

19Cited by
2References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 26, 1994
Grant dateNov 21, 1995
Priority date
Expiry dateJul 26, 2014

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/12
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

An exhaust gas-purifying system for an internal combustion engine is provided with hydrocarbon-adsorbing catalyzer for adsorbing unburnt gas components present in exhaust gases. At least one exhaust gas-purifying catalyzer is arranged in the exhaust passage at a location downstream of the hydrocarbon-adsorbing catalyzer. A bypass passage bypasses the hydrocarbon-purifying catalyzer. A changeover valve is arranged in the exhaust passage at a branchpoint between the bypass passage and the exhaust passage, for selecting a first flow path in which exhaust gases are guided to the unburnt gas component-adsorbing catalyzer, or a second flow path in which exhaust gases are guided through the bypass passage. First and second exhaust gas concentration sensors are arranged in the exhaust passage at locations upstream and downstream of the hydrocarbon-purifying catalyzer. An ECU controls the changeover valve to select the first flow path or the second flow path, based on outputs from the first and second exhaust gas concentration sensors.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.