Abstract: 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.

Abstract: 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.

Abstract: A screening apparatus, in particular for mixtures, which are difficult to separate, as e.g. crude oil sand mixtures, comprising a base support frame, aligned substantially horizontally, supported relative to the support floor through damping springs as an opposite oscillating mass; several inclined energy storage spring packages, each provided as a double coil spring assembly, carrying a screening box as an oscillating mass; and several unbalanced mass motors, flanged to the base support frame, imparting an oriented box oscillation with an effective KV value of 9.5 upon the base support frame and through the energy storage spring packets upon the sieve box.