Institute of Problems of Mechanical Engineering of the Russian Academy of Sciences (St. Petersburg, Russia):

Blekhman I. I., Head of Laboratory, Doctor of Physical and Mathematical Sciences, Professor, iliya.i.blekhman@gmail.com

REC «Mekhanobr-Tekhnika» (St. Petersburg, Russia):
Blekhman L. I., Leading Researcher, Candidate of Engineering Sciences, liblekhman@yandex.ru

Lutsk National Technical University (Lutsk, Ukraine):
Yaroshevich N. P., Head of Chair, Doctor of Engineering Sciences, Professor, yaroshevichmp@gmail.com

Drive oscillations of vibratory machines with inertial unbalance vibration exciter are considered in this paper. In this type of machines electric motor shaft is connected with exciter shaft through an element that allows relative shafts offset (elastic coupling, V-belt transmission, cardan shaft). This connection of shafts is specific for vibratory screens, conveyors, feeders and other machines with electric motor installed on immovable foundation and exciter shaft — upon machine vibrating body. It is shown that presence of the shafts connection in question introduces significant specifics into machine drive dynamics. Body of vibratory machine with inertia excitation is usually supported by cushioned antivibration mounts. With that, natural frequencies of machine body on supports are several times lower, than operating frequency of body vibrations. As a result, during start-up and running-out system attains a condition of resonance, followed by violent vibrations, and, sometimes, with insufficient motor power, rotational frequency crawling in the vicinity of relevant natural frequency (Sommerfeld’s effect). These special aspects must be taken into consideration in machines design, in order to avoid a condition of hazardous vibrations both in start-up and steady state operation.
The study was performed on the basis of vibrational mechanics approach and direct motion separation method. The theoretical results are compared with the computerized simulation results. The studies were performed with the aid of the Russian Science Foundation Grant (Project No. 17-79-30056).

1. Vaisberg L. A. Vibrating screens. Vibrations in technology. Reference book. Vol. 4. Vibration processes and machines. Moscow: Mashinostroyeniye, 1981. pp. 349–352.
2. Vaisberg L. A. Design and calculation of vibrating screens. Moscow: Nedra, 1986. 144 p.
3. Vaisberg L. A. New vibrating screens for the building materials industry. Promyshlenno-stroitelnoye Obozreniye. 2011. No. 8. p. 29.
4. Vaisberg L. A., Zarogatskiy L. P. New equipment for crushing and grinding materials. Gornyi Zhurnal. 2000. No. 3. pp. 49–52.
5. Kolovskiy M. Z. The study of the dynamics of the steady motion of a machine unit with an elastic gearing. Izvestiya AN SSSR, Mashinovedeniye. 1985. No. 2. pp. 40–47.
6. Astashev V. K. Vibrating drive. Ch. 9. In: Mechanical engineering. Encyclopedia. In 40 vol. Vol. IV-2. The electric drive. Hydro and vibration drives. In 2 bk. Bk. 2. Hydro and vibration drives. Moscow: Mashinostroyeniye, 2012. pp. 245–303.
7. Dresig H., Holzweissig F. Dynamics of machinery. Theory and application. Berlin, Heidelberg: Springer, 2010. 544 p.
8. Dresig H., Fidlin A. Schwingungen mechanischer Antriebssysteme: Modellbildung, Berechnung, Analyse, Synthese. Berlin, Heidelberg: Springer, 2014. 651 p.
9. Fidlin A., Ineichen L., Kremer E., Klunder D., Tikhomolov A. Schwingungen im Kupplungsbetatigungssystem: Von der Kurbelwelle bis zum Pedal. VDI – Berichte 2077, 6; Fachtagung Schwingungen in Antrieben. Dusseldorf: VDI Verlag, 2009. pp. 143–152.
10. Blekhman I. I. Vibrational mechanics (Nonlinear dynamic effects, general approach, applications). Singapore: World Scientific, 2000. 509 p.
11. Blekhman I. I. Theory of vibration processes and devices. Vibration mechanics and vibration technology. St. Petersburg: «Ruda i Metally» Publishing House, 2013. 640 p.
12. Blekhman I. I., Indeitsev D. A., Fradkov A. L. Slow motions in systems with inertial excitation of vibrations. Problemy Mashinostroyeniya i Nadezhnosti Mashin. 2008. No. 1. pp. 25–31.
13. Kremer E. B. Slow motion in systems with modulated excitation. Journal of Sound and Vibration. 2016. Vol. 383. pp. 295–308.
14. Yaroshevich N. P., Silivoniuk A. V. About some features of run-up dynamic of vibration machines with self-synchronizing inertion vibroexciters. Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu. 2015. No. 4. pp. 37–45.