The analysis of private tests is presented in the article. The applicable tests refer to accelerations, the level of the sound pressure as well as to the sound power emitted by the passenger lift cabin at different technical conditions of the lift. For a group of lifting devices the accelerations were tested at three axes with the use of an accelerometer. The accelerometer was placed in the central part of the cabin with simultaneous measurement of the acoustic parameters with the sound analyzer equipped with sound volume double microphone probe. An attempt was made to determine the impact of the frame -cabin system construction as well as the lift's technical condition on the recorded parameters. It can allow to establish the limit values of the lift structure parameters under which a rapid drop of comfort takes place, while travelling in the lift as well as to indicate those construction elements the modification of which would affect the improvement of the operation noiselessness.
The article presents the results of investigations into the depth of the plastically deformed surface layer in the roller burnishing process. The investigation was carried out in order to obtain information on the dependence relationship between the depth of plastic deformation, the pressure on the roller and the braking torque. The research was carried out according to the original method developed by the authors, in which the depth of plastic deformation is increased by applying a braking torque to the burnishing roller. In this method, it is possible to significantly increase (up to 20%) the depth of plastic deformation of the surface layer. The tests were carried out on a specially designed device on which the braking torque can be set and the force of the rolling resistance of the roller during burnishing can be measured. The tests were carried out on specimens made of C45 heat-treatable carbon steel. The dependence of the depth of the plastically deformed surface layer was determined for a given pressure force and variable braking moments. The depth of the plastically deformed layer was measured on the deformed end face of the ring-shaped samples. The microhardness in the sample cross-section and the evolution of the microstructure were both analysed.
The article presents the results of a part of research conducted by the authors into a wide range of work on automation of public safety systems. Their main purpose is to create, on the basis of sound signals analysis, system of warning against the use of firearms monitored public places not only at the time of shooting, but at the stage of preparing - the firearm reloading process. The range of acoustic measurements presented in the article and their analyzes included variability of sound emission of selected type of firearms depending on the number of operations and thus the degree of wear. Analysis of the recorded data will allow in the future to develop a system enabling not only to determine a type of firearm or tp narrow down the search area of individual specimens, but also to determine the degree of wear in terms of suitability for further use. The results discussed in the article correspond to two states of the same firearm model. The first is the initial state from the manufacturer’s factory after returning 50 control shots, the other after over 20,000 cycles. The used firearm was technically fully efficient, with no need to replace the elements during operation as well as tests. The presented scope of measurements includes spectral analysis of sound in the near field and time analysis of sound emission levels in the successive operation phases of the firearm mechanisms.
W artykule przedstawiono wstępne wyniki analizy sygnałów akustycznych emitowanych przez wybrane typy broni. Przedstawiona w opracowaniu część wyników przeprowadzonych badań dotyczy fazy przygotowania broni do strzału. Pomiary akustyczne zrealizowano z zastosowaniem analizatora dźwięku firmy Bruel&Kjaer 2260 Investigator wraz z dwumikrofonową sondą natężenia dźwięku B&K 3595 oraz szerokopasmowego analizatora cyfrowego DSO-2902.
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