Piston engine monitoring esp. for piston seizure development - by comparing angular speed-position relationship with ideal characteristic curve

摘要

A monitoring method for piston engines is esp. for detecting, locating, and recording cylinder efficiency differences and/or piston seizures is applicable to diesel engines, compressors, and steam engines, etc. It covers all types of fault, but partic. small frictional efficiency losses at the onset of piston seizure. The crankshaft angular speed is measured as a function of the angular position and compared with an ideal curve. The location and cause of the fault are determined from deviations from the ideal relationship. A toothed disc working with an optical or magnetic pick-up system has a large number of teeth to provide max. angular resolution. The angular speed is derived from the torque cycle or acceleration sign changes. The variation of angular speed w.r.t. position or of angular speed referred to engine power is used as an engine efficiency indicator.