A circle throw screening machine for screening particulate material according to size is described. The machine comprises a housing (2) having a longitudinal aspect, an upper perforated deck (7), a frame (3) configured for mounting the housing, and a suspension system (4) for mounting the housing to the frame and configured to allow vibration of the housing relative to the frame. Three rotatable unbalanced drive shafts (5) are coupled to the housing (2) and configured to vibrate the housing in response to rotation of the drive shafts, wherein the three rotatable unbalanced drive shafts are equally spaced along the longitudinal aspect of the housing. A drive mechanism (6) is coupled to the unbalanced drive shafts (5) and configured to effect synchronous rotation of the three drive shafts in the same direction.

An apparatus that generates vibrational motion is disclosed. The apparatus includes a first mass, a second mass, a drive system, and a control system. The first mass is eccentrically mounted on, and configured to rotate about, a first shaft. The second mass is eccentrically mounted on, and configured to rotate about, a second shaft, with first and second shafts sharing a common axis. The drive system imparts rotational motion to first and second shafts, and the control system controls rotational frequencies, directions, and initial angles of the first and second masses. Linear, elliptical, or circular vibratory motion of the apparatus may be induced by controlling such rotational properties of the first and second masses. The apparatus may include a measurement device that measures angular position and/or velocity of the first and second masses. The control system may control the vibrational motion based on measurements taken by the measurement device.

This disclosure is drawn systems, devices, apparatus, and/or methods related to the separation of a mixture of solids according to size and the separation of solids from liquid. Specifically, this disclosure is drawn to an adjustable weight set for use on vibratory separators. In some examples, the adjustable weight set may include a base plate rotatable about an axis and extending radially outward from the axis; a plurality of slots extending through the base plate and being disposed between a radially outward periphery of the base plate and the axis; a plurality of weights coupled to each other about the base plate; and a weight locking tab that partially surrounds the base plate that may include one or more hooks extending through a portion of a slot.

A vibratory drive system, suitable for a material screening apparatus, includes rotatable drive shafts each having a centre of mass offset from its rotational axis. A respective drive mechanism is coupled to each drive shaft and is controlled by a controller. The controller adjusts the relative rotational speed of the drive shafts to adjust the relative angular position of the respective centre of mass of the drive shafts. This adjustment allows the vibratory characteristics of the drive system to be changed without having to halt the drive system.

Vibratory material classifiers are disclosed. Some embodiments include eccentric shaft assemblies having removable eccentric weights. Some embodiments include oil access and indicator conduit extending from the interior to the exterior of a classifier.

An apparatus that generates vibrational motion is disclosed. The apparatus includes a first mass, a second mass, a drive system, and a control system. The first mass is eccentrically mounted on, and configured to rotate about, a first shaft. The second mass is eccentrically mounted on, and configured to rotate about, a second shaft, with first and second shafts sharing a common axis. The drive system imparts rotational motion to first and second shafts, and the control system controls rotational frequencies, directions, and initial angles of the first and second masses. Linear, elliptical, or circular vibratory motion of the apparatus may be induced by controlling such rotational properties of the first and second masses. The apparatus may include a measurement device that measures angular position and/or velocity of the first and second masses. The control system may control the vibrational motion based on measurements taken by the measurement device.

The vibrating screen have a screen deck, two sidewalls and a mechanical vibrator comprising two shafts, rotating at the same rotation and in opposite directions, each one of the end portions of each shaft carrying an eccentric weight and being supported on bearings which are supported in the sidewalls of the vibrating screen. The shafts have their end portions, adjacent to each other, supported on bearings mounted to a same bearing case fixed to beams, transversal and having opposite ends fixed to the sidewalls of the vibrating screen. Each end portion of a shaft carries an eccentric weight with a total mass different from that one of the eccentric weights of the end portions of the other shaft, said shafts rotating in determined phases, defining the inclination of the major axis of an elliptical movement imparted to the screen deck.

A circle throw screening machine for screening particulate material according to size is described. The machine comprises a housing (2) having a longitudinal aspect, an upper perforated deck (7), a frame (3) configured for mounting the housing, and a suspension system (4) for mounting the housing to the frame and configured to allow vibration of the housing relative to the frame. Three rotatable unbalanced drive shafts (5) are coupled to the housing (2) and configured to vibrate the housing in response to rotation of the drive shafts, wherein the three rotatable unbalanced drive shafts are equally spaced along the longitudinal aspect of the housing. A drive mechanism (6) is coupled to the unbalanced drive shafts (5) and configured to effect synchronous rotation of the three drive shafts in the same direction. The machine can achieve high acceleration of 6.4G and 9.7G through the use of two or three parallel shafts respectively (NB. 2 shafts is suffice for a G of 6.4 and 3 shaft is suffice for 9.7G) distanced from each other by a distance of about one quarter of the length of the deck, configured for synchronous rotation.

An impulse mechanism for a vibratory device includes an eccentrically weighted shaft that is adapted to be rotated to create vibratory forces. A fan component is mounted on the eccentrically weighted shaft. The fan component has a plurality of fan blades spaced around its periphery.

A screening system for screening material, in particular for screening mineral rock, the system having a screen box, with two outer side walls. At least two vibration systems are arranged on each of the two side walls to excite vibration. The two side walls each have at least two vibration nodes in accordance with a bending mode, at least two crossmembers, which connect the two side walls to one another, at least one screen deck, which is supported on the at least two crossmembers. The two vibration systems on each of the side walls are arranged such that each vibration system is arranged in the region of a vibration node of the respective side wall. The disclosure also relates to a method for screening material to be screened, in particular for screening mineral rock, via a screening system of the aforementioned type.