Method and means for determining air mass in a crankcase scavenged two-stroke engine
US4958516A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 8, 1990 |
| Grant date | Sep 25, 1990 |
| Priority date | — |
| Expiry date | Feb 8, 2010 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D2400/04
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A method and apparatus 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 crankcase chamber, prior to its transfer to a 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.