Patent · US Expired

Method and means for determining air mass in a crankcase scavenged two-stroke engine

US4920790A · kind A · utility

10Cited by
6References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 10, 1989
Grant dateMay 1, 1990
Priority date
Expiry dateJul 10, 2009

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02D2400/04
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A method and means are described for determining the mass of air available for combustion within a cylinder of a crankcase scavenged two-cycle engine, without the use of a mass-air flow sensor. This is achieved by estimating the mass of air under compression within a crancase chamber, prior to its transfer to the cylinder combustion chamber. The estimate for air mass is based upon the integration of crankcase pressure over the interval of decreasing crankcase volume, while air within the crankcase is under compression. The volume of the air within the crankcase chamber is derived as a function of engine cycle position, with crankcase air temperature being derived as a function of intake air temperature. Air pressure during compression is monitored with a crankcase pressure sensor. The estimate for air mass is corrected to account for air leakage and incomplete transfer of the air between the crankcase and combustion chambers.

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