| 摘要 |
FIELD: machine building. ^ SUBSTANCE: invention relates to designing, testing and diagnosing ICE systems and mechanisms, particularly to methods aiming at determining the total moment of mechanical losses originating in cranking with no fuel feed into cylinders, and can be sued in development of devices designed for thermal preparation of ICE at low ambient temperatures as well as for checking up its state in assembling, running-up and operation. Proposed method consists in cranking engine crankshaft by starter with constant rpm and with no fuel fed. Total moment of mechanical losses MTc of cold engine is measured with auxiliary mechanisms running and idle MTc without aux. The moment of engine mechanical losses with warmed-up group MTh WUG is measured with cold crank gear. Total moment of mechanical losses of hot engine MTh is measured. Cold engine is decompressed. Moments of mechanical losses are measured at cranking with valve gear running MTêéc WGR and idle MTêéc with no rotation. Components of the total moment of mechanical losses of cold engine MTc: MTc VG - of friction forces in valve gear; MTc P for overcoming pump loses; MTc AUX for auxiliary mechanism drive; MTc CG for friction forces in crank gear; MTc CPG for friction forces in cylinder-piston group, are defined from the following equation: MTc VG = MTêéc VG - MTêéc withut revolution; MTc P = MTc - MTêéc CPG; MTc = MTc- MTc without AUX; MTc CG = MTc CPG - MTc - MTc VG - MTcp - MTc AUX; MTc CPG = MTc - MTh - MTc CG - MTc VG - MTc P - MTc AUX. ^ EFFECT: higher accuracy of determination of ICE mechanical loss total moment. ^ 2 cl |
