Ukrainian Journal of Mechanical Engineering and Materials Science

Permanent URI for this communityhttps://ena.lpnu.ua/handle/ntb/31565

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    Substantiation of parameters and analysis of operational characteristics of oscillating systems of vibratory finishing machines
    (Lviv Politechnic Publishing House, 2017-10-19) Korendiy, Vitaliy; Zakharov, Viktor; Lviv Polytechnic National University; ISKRA PJSC
    The calculation diagrams of oscillating systems and operation features of vibratory finishing machines are considered. The mathematical models of three-mass and four-mass oscillating systems are presented. The amplitude values of the oscillating masses displacements are derived. The functions of inertial and stiffness parameters optimization are formed. The optimization problems are solved with a help of MathCAD software. On the basis of synthesized inertial and stiffness parameters, the amplitude-frequency characteristics of the oscillating systems of vibratory finishing machines are formed and analyzed. In order to verify the validity of the proposed theoretical approaches, the simulation of the mathematical model of the oscillating system motion is carried out by means of numerical solving of the system of differential equations of the oscillating masses motion. The proposed structural diagrams and the operation schemes of the vibratory finishing machine, as well as the derived analytical formulas may be used by designers, researchers and technologists while improving existent and developing new equipment for vibro-finishing treatment.
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    Optimization of structure of sorting vibratory separators
    (Lviv Politechnic Publishing House, 2017-01-01) Shenbor, Vladyslav; Korendiy, Vitaliy; Brusentsov, Volodymyr; Lviv Polytechnic National University, Lviv, Ukraine
    The problem of substantiation of operational efficiency of vibratory separators designed on the basis of vibratory hopper feeders with electromagnetic vibrations exciters and with conic working bowls is considered in the article. The complex of factors influencing the accuracy and productiveness of separation of coins and disk-shaped products on two or more fractions is overviewed. New models of structures for the effective solution of separation problems are proposed. The design of a highly-efficient and high-performance separator with independent oscillations disturbance is described. The results of experimental investigations of vibratory transportation in elliptical modes of vibrations and of the study of separation efficiency are presented. The recommendations that developers and researchers of such devices may use are given.
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    Two-mass vibratory conveyor-manipulator with three-component electromagnetic drive
    (Publishing House of Lviv Polytechnic National University, 2016) Vrublevskyi, Іgor
    Vibratory conveyor with three-component oscillations provides the opportunity to move the piece goods and details for any trajectory on a plane. Phase difference between independent horizontal (longitudinal or transverse) and vertical (normal) oscillations releases elliptical vibration of conveyor in plane perpendicular to the conveyor’s track. Elliptical vibrations allow increasing conveying velocity and inclination angle of conveyor’s track in comparison with the simplest linear vibrations. Three-component oscillations of the conveyor’s track are implemented by independent exciters of oscillations in the direction of conveying (longitudinal oscillations), oscillations in the direction perpendicular to conveying in plane (transverse oscillations) and oscillations in the direction perpendicular to conveying plane (normal oscillations) with phase difference between them. Conveying velocity of details moving upon the track varies with the change of phase difference angle and reaches a maximum with a certain angle, depending on several parameters. When electromagnetic exciters of longitudinal and normal oscillations are turned on, conveying details move in longitudinal direction. When electromagnetic exciters of transverse and normal oscillations are turned on, conveying details move in transverse direction. When electromagnetic exciters of longitudinal and transverse oscillations are turned on, conveying details rotate around their axes. When all three exciters are turned on, conveying details move at any trajectory. The change in the ratio of longitudinal and transverse amplitudes and phase difference angles between them allows changing the trajectory of details moving on conveyor’s track, making them not only move forward but rotate as well. That’s why such conveyor can be called a manipulator. The resilient system of two-mass vibratory conveyor-manipulator with three-component oscillations should have elastic pliability in three mutually perpendicular directions. It includes four resilient elements; each of them consists of two latticed leaf springs, fixed at the right angle to each other. The working body with conveying track is joined with reactive frame by resilient elements. Electromagnetic drive includes four electromagnetic exciters of longitudinal oscillations, four electromagnetic exciters of transverse oscillations and one electromagnetic exciter of normal oscillations. The bodies of electromagnets are fixed on the reactive frame and their anchors are fixed on the working body of conveyor-manipulator. A block diagram of the electrical control of conveyor-manipulator is referred. A voltage is supplied from two phases of threephase electricity to the coils of electromagnets through diodes, auto-transformers, switches and phase-shifter. The amplitudes of oscillations are regulated with aid of auto-transformers, phase difference between them and the change of conveying modes are carried by switches and phase-shifter. The oscillating system of vibratory conveyor-manipulator has six degrees of freedom and respectively six frequencies of natural oscillation. The formulas for calculating the vibratory conveyor-manipulator’s frequencies of natural oscillation are derived. Vibratory conveyor-manipulator with three-component electromagnetic drive was designed and manufactured. Its research and testing show the possibility of conveying details and piece goods at any trajectory.