Oscillation modes of vibrating feeders with vibro-impact adaptive drive at the output of reflacted ore from chambers of wining blocks

Abstract

The oscillation modes of vibrating feeders with vibro-impact adaptive drive are researched, which are intended for output and loading of reflacted ore from chambers of wining blocks at underground mining, or other bulk media from bunkers and so on, under complicated vibration conditions. The resonant polyfrequency oscillations of the impactor of the vibro-impact drive of feeders with such drive in vibro-impact modes are excited, which through one-side elastic elements are transmitted to the feeder tray, and in the pillar of the reflacted ore in the chamber above the tray. With increasing load from the ore on the tray there is an increase in the intensity of the impactor vibration of the feeder vibro-impact drive with accelerations in hundreds m/s2. Such oscillations increase the depth of dissemination of vibrational effects in a pillar of reflacted ore above the tray, which increases the efficiency and productivity of vibration output. Depending on the feeders parameters in its oscillatory system, various modes of vibro-impact oscillations are excited. The task of choosing the mode of variation of the feeder is to choose such parameters, which would ensure efficient vibration output of the rock mass and reliability of its operation.

Comparative analysis of the VPR-4M vibrating feeder dynamics for the reflected ore output from the outlets and its modernized analog with a vibro-impact adaptive drive

“…Comparative studies of feeders were carried out using a mathematical model of vibrating feeder with vibro-impact adaptive drive [1,2,5], which, with the appropriate parameter setting, it is possible to study typical feeders as a single-mass dynamic system with inertial debalanced vibrator rigidly fixed to the feeder, for example, such as VPR-4M type.…”

“…The increase in the productivity of vibration ore putput is possible with vibro-impact polyfrequency excitation of the feeder tray [1,2] by adapting the parameters of its oscillations to load changes and increasing the spread of polyfrequency oscillations in the rock column above the tray in the outlet which reduces the probability of the reflected rock mass hangs.…”

“…Problems of highly productive output and loading of ore into vehicles are partially solved by using vibrating feeders, which are installed under the outlet and excite the reflected ore over the working body (tray) of the feeder [1][2][3][4]. Due to this, in comparison with other methods of production (for example, scraper or gravity leakage), when ore outputs by vibrating feeders, the probability of formation of vaults from jammed pieces of ore in outlet and its hangs decreases, which increases mining productivity and safety.…”

“…In addition to these, single-mass vibrating feeders have the following disadvantages that impair the efficiency of their work [1][2][3][4]6]:…”

“…Overcoming the disadvantages in the work of typical vibrating feeders, which reduce the vibration ore output productivity, is possible when the feeder tray is excited by a vibro-impact adaptive polyfrequency drive [1,2,5]. This drive adjusts the oscillations parameters to change the load from the reflected ore on the feeder tray, the normal start and oscillations of the vibrating tray at any load from the ore on it, the spread of oscillation in the rock massif due to excitation of the polyfrequency oscillation spectrum.…”