![]() The measuring range of the device is from 30 to 130 dB, with the frequency of the measured signal in the band ranging from 20 Hz to 8 kHz. This class of device is recommended by ISO 18738-1: 2012. The sound level measurements were carried out using the Center 390 device in accordance with the IEC 61672-1 class 2, ANSI S1.4 type 2 standard, equipped with a capacitive electret microphone. As a consequence, higher levels of vibration and noise also occur inside the cabin. The location of the drive in the shaft causes higher-level vibration and noise in the panels compared to other types of lifting devices. While in operation, the drive system generates vibration which-via the foundation and guideways-passes through the guides and the cabin frame to the inside of the cabin. The walls of the cabin are made of steel panels covered with HPL laminate (thermoset laminate) with a thickness of 1 mm. The lift is equipped with a one-speed machine adjustable with an encoder and sliding guides. The detail specification is as follows: installation year-2014 capacity Q = 750 kg speed V = 1 m/s engine speed on the drive shaft 168 rpm length of guides 6 × 5000 mm lifting height H = 25,000 mm number of stops N = 9 depth and width of the cab A = 1400 mm and B = 1300 mm balance of the system-48% (Mk. ![]() The research object is a passenger lift for nine people with a driving system installed in a reinforced concrete shaft. ![]() We take advantage of the Hilbert–Huang transform that was designed specifically for analyzing data from nonstationary signals. In this paper, we follow previous studies on passenger comfort assessment in terms of lift acceleration. Moreover, the tests aimed to investigate the above phenomena in terms of decreasing the structure’s noise levels as well as of using them in a diagnostic process focused on monitoring passenger comfort. The primary objective of tests undertaken in this study was to determine vibroacoustic phenomena occurring in lifting devices. In this study, the technical condition is recognized as a set of parameters of the lift structure that affect passenger comfort. Ī survey of the literature reveals a lack of publications regarding methods that would use vibroacoustic phenomena to evaluate the technical condition of lifting devices. Measuring methods and reduction of acoustic emission in the passenger lift cabin. Vibration isolation methods for the lift door power drive and the selection of vibration isolation materials Vibration and noise generated by various lift components such as slide rollers Selected aspects of vibroacoustic phenomena occurring in lifting devices were discussed in the literature of the subject. Additionally, the available standards contain a methodology for measuring vibrations in X, Y, Z directions. Acceptable sound levels in the passenger cabin and in the lift machine room as well as general requirements regarding noise and vibration prevention are normalized. Regardless of the solution type, every lifting device should be designed such that travel comfort, defined as physiological and psychophysical states in which a traveling person feels good and safe, is as high as possible. Roller guides (cabins)-their wear caused by wiped polymeric material or rolling bearing damage is one of the most common reasons for excessive noise. Machine-the main reason for intensified sounds of the machine is its improper isolation from the ground, which leads to the creation of vibrations that are transferred to other elements of the structure, Tie rods (ropes, belts) and rope pulleys which, depending on the construction, emit sounds during cooperation with the machine and the output wheel, and additionally may be a carrier of vibrations from the spring suspension system of the counterweight,Ĭounterweight slide guides-depending on the material used, the inserts can emit sound during contact with the counterweight guide (this phenomenon is particularly intensified in the case of improper lubrication of guides), The main structural elements of a passenger lift significantly affecting the level of generated vibration and noise include: The driving system is a machine with a traction sheave and a diverter pulley enabling appropriate descent of the ropes. ![]() The frame-cabin system is connected by ropes with a balancing mass (counterweight) which also moves along the guides using its own guide system equipped with counterweight guides. The passenger cabin is installed in the cabin frame equipped with guides along which the guiding system moves (guide elements).
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