Patent · US Expired

EGR rate estimation system for internal combustion engine

US5505174A · kind A · utility

23Cited by
9References
28Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 13, 1995
Grant dateApr 9, 1996
Priority date
Expiry dateApr 13, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/40
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A system for estimating an exhaust gas recirculation rate for an internal combustion engine. In the system, the EGR rate when its operation is steady is first determined to a desired value with respect to the engine operating conditions at least including the engine speed and the engine load, then the EGR rate is estimated as; EGR rate=(steady-state EGR rate).times.{(gas flow rate QACT determined by the actual valve lifting amount and the ratio between the upstream pressure and the downstream pressure of valve)/(gas flow rate QCMD determined by a command value and the ratio between the upstream pressure and the downstream pressure of valve)} A delay time until the recycled gas enters the combustion chamber is determined and one from among the EGR rates or a fuel injection correction coefficients calculated therefrom consecutively is selected.

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