Apparatus and method for analyzing events for an internal combustion engine
US5359883A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 1993 |
| Grant date | Nov 1, 1994 |
| Priority date | — |
| Expiry date | Aug 16, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M15/08
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
In one aspect of the present invention, an apparatus for analyzing a plurality of events of an internal combustion engine is provided. A crankshaft sensor monitors the rotational position of the crankshaft and responsively produces a crankshaft pulsetrain. A cylinder pressure sensor senses the pressure produced in the engine cylinder and responsively produces a cylinder pressure signal. A memory device stores previously calculated values representing engine cylinder volumes at predetermined crankshaft positions. A microprocessor determines the start of combustion for an occurring engine cycle in response to a cylinder pressure signal magnitude, P.sub.2, at a current crankshaft position being equal or greater than the relationship: EQU P.sub.1 (V.sub.1 /V.sub.2).sup.n where, P.sub.1 equals the cylinder pressure corresponding to a previous crankshaft position, V.sub.1 equals cylinder volume corresponding to the previous crankshaft position, V.sub.2 equals the cylinder volume corresponding to the current crankshaft position, and n equals a predetermined polytropic value. Advantageously, the start of combustion is determined prior to the next occurring engine cycle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.