Fedoskina О. V. The influence of passive cheek mass in the vibratory grinder on resonance frequencies of its elements
- Details
- Parent Category: Geo-Technical Mechanics, 2018
- Category: Collection of scientific papers «Geotekhnicheskaya Mekhanika» Issue 140
Geoteh. meh. 2018, 140, 42-49
DOI: https://doi.org/10.15407/geotm2018.03.042
THE INFLUENCE OF PASSIVE CHEEK MASS IN THE VIBRATORY GRINDER ON RESONANCE FREQUENCIES OF ITS ELEMENTS
1Fedoskina О. V.
1National Technical University «Dnipro Polytechnic»
UDC621.926.085:62-868
Language: Ukrainian
Abstract.
Creation of grinder design with a wide possibility of controlling the disintegration process can be carried out on the basis of the constructive scheme of the grinder with inclined working chamber. However, insufficient amount of analytical and experimental researches, absence of methods for calculating such class of machines hinders their practical application. The vibratory grinder with an inclined working chamber includes the following main elements: passive cheek on the shock absorbers, active cheek pivotally mounted in the body and connected with it by means of elastic connections, two-shaft inertial vibration exciter. On the basis of the developed mathematical model of vibratory grinder, which describes movement of its elements in idle mode and establishes the relationship between dynamic and design parameters, the amplitude-frequency characteristics are obtained and natural frequencies of its elements are determined. The behavior of resonant frequencies was studied when mass of the passive cheek varied within 100 kg - 1000 kg. At the same time, mass of the active cheek remained unchanged and made 100 kg. It is shown that the most intensive decrease of the upper resonant frequency values occurs with the mass ratio of active and passive cheeks 1: 4. With mass ratio of 1: 8 or more, the upper resonance frequency practically does not change its value. With a slight difference in the masses of the active and passive cheeks, resonant frequencies cover a significant frequency range of the disturbing force. An increase of passive cheek mass leads to decrease of resonant zone and its shifting towards low frequencies. Range of resonant frequencies, which affects the transient processes at the start and stop of the grinder, decreases to mass ratio of 1: 2.5.
The studies show that passive cheek mass is a parameter that allows changing width of the resonant frequency region and shifting this region along the frequency axis. At the same time, there is a limiting value of mass (for specific initial data), the increase of which does not give tangible results in the variation of the amplitude-frequency characteristic of the grinder. The results obtained allow determining minimum mass of the passive cheek.
Keywords: vibratory grinder, passive cheek, frequency, mass.
References:
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About the authors:
Fedoskina Olena Valeryevna, Candidate of Technikal Sciences (Ph.D), Assistant in the Department of the Fundamentals of Designing Machines and Mechanisms, National Technical University “Dnipro Polytechnic”, Dnipro, Ukraine, fedoskina.ev@gmаil.com