The aim of this paper is an investigation of damping properties of polyurethane materials that were produced from polyurethane foam granules. There were used polyurethane materials with different thickness and inertial masses. After measurements of damping vibration, the polyurethane samples were compared and recommended in reference to their damping properties. and Tématem tohoto příspěvku je vyšetření tlumících vlastností polyuretanových materiálů vyrobených z polyuretanových pěnových granulí. Byly použity polyuretanové materiály s různými tloušťkami a setrvačnými zátěžemi. Po provedení měření útlumů vibrací polyuretanových vzorků byly jednotlivé vzorky porovnány a doporučeny z hlediska jejich tlumících vlastností.
The paper deals with mathematical modelling of dynamic response of the electric locomotive wheelset drive caused by short-circuit traction motor torque. The individual wheelset drive is composed of five subsystems - rotor of the traction motor with driving gear, driven gear, stator of the traction motor with gear housing, hollow graduated shaft with clutches and wheelset. The couplings between subsystems are linearized in dependence on longitudinal creepage and locomotive forward velocity before sudden short-circuit in the asynchronous traction motor. In comparison with previous models of the wheelset drives, the rotor of the electromotor is characterized by flexible shaft suppported on flexible rolling-element bearings. The sheet metal packjet of cylindrical shape is connected by parallel cooper bars with two short circuit rings. In conseqquence of strong excitation an interruption of gear mesh can be observed. This nonlinear effect and dynamic load of individual wheelset drive with large number of DOF is investigated using the condensed mathematical model created by model synthesis method. and Obsahuje seznam literatury