Bezdemontazni diagnostika spalovacich motoru z vyhodnoceni prubehu okamzite uhlove rychlosti klikoveho hridele.

A measurement system and an associated processing signal for determining of the accurate instant angular speed of a crankshaft is presented in this PhD thesis. The used method is based on the recalculation of the angular velocity from intervals of passing marks, e.g. gear tooth on the flywheel, along a sensor. The detailed analysis of errors was carried out. Systematic errors are those of quantization due to the non-uniform distribution of the teeth along the flywheel circumference and due to the wear of them. Possibilities of their suppression are discussed, principles of suitable selection of the sensor arrangement in the relation to the measured marks are presented and an optimal alternative was chosen. The random errors are excited with the engine and sensor vibrations of different frequencies. An original method based on subtraction of the reference record from the measured record is used. The reference record is in ideal case a signal gained from the uniform rotational motion exerted by a foreign energy source. This ideal instant was realised in the practical form as the rotational motion of an engine with the zero fuel, when only centrifugal forces of the inertial masses and the compression pressures are present. This kind of the evaluation affords an essentially better accuracy. The possibility of using of non-dismantling diagnosis was proved by means of signals measured on a two-cylinder engine, with the crank turned through an angle of on which the representative defects in praxis usually occurred were simulated.Available from STL Prague, CZ / NTK - National Technical LibrarySIGLECZCzech Republi