Patent · US Expired

Engine mixture control system controlling primary and secondary air-fuel mixtures

US4385491A · kind A · utility

13Cited by
7References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 31, 1980
Grant dateMay 31, 1983
Priority date
Expiry dateDec 31, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02A50/20
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

An internal combustion engine includes an intake system, an exhaust system, and a mixture supply device which supplies primary fuel-air mixture into the intake system. An oxygen sensor assembly detects oxygen concentration at a certain point in the exhaust system and produces a first electrical signal which represents this concentration. A secondary air flow control circuit receives this first electrical signal and produces a second electrical signal according thereto. A secondary air supply system feeds secondary air into the exhaust system upstream of the aforementioned certain point at a flow rate controlled by the second electrical signal. A primary air/fuel ratio correction circuit receives either the first or the second electrical signal and based on it produces a primary mixture control electrical signal. This primary mixture control electrical signal is received by a mixture control system, which alters the primary air/fuel ratio of the mixture provided by the mixture supply device in accordance therewith.

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