Patent · US Expired

Combustion state determination method of internal combustion engine

US7448253B2 · kind B2 · utility

2Cited by
4References
6Claims
0Family size

Assignees

Inventors

Key dates

Filing dateAug 3, 2005
Grant dateNov 11, 2008
Priority date
Expiry dateOct 5, 2025

Classification

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

Abstract

The present invention is a combustion state determination method of an internal combustion engine for detecting an ion current which is generated in a combustion chamber at combustion of the internal combustion engine in a detection period to determine a combustion state, comprising steps of detecting a primary combustion period on the basis of a first ion current which forms the detected ion current and occurs immediately after ignition, detecting a secondary combustion period on the basis of the ion current which occurs after disappearance of the first ion current when at least the detected primary combustion period is normal, determining the combustion state on the basis of the detected primary combustion period when the secondary combustion period is smaller than a predetermined value, and determining the combustion state on the basis of a whole combustion period from start of the detection period of the ion current to end of the last secondary combustion period in the detection period when the secondary combustion period is larger than the predetermined value.

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