GB1137921A - Vibratory screens, conveyors and the like - Google Patents

Abstract

1,137,921. Jigging conveyers. AUTOPACK Ltd. 3 May, 1966 [25 Feb., 1965], No. 8118/65. Heading B8A. [Also in Divisions B2 and F2] A vibratory conveyer, as described, or a vibratory screen is driven by a mechanism comprising a link 16, Fig. 3, the ends of which are respectively pivotally connected to the conveyer and to an oscillating member 17 pivotally mounted on a framework supporting the conveyer, the pivot axis of the link 16 with the member 17 being slidably movable into and out of alignment with the pivot axis 20 of the member 17 with the framework, for varying the amplitude of the vibrations of the conveyer. The latter comprises three trays 10, 11, 12, Fig. 2, the trays 10, 11 being broad and the central tray 12 being narrow and forming a dribble feeder. The trays 10, 11 are suspended by parallel hangers 13, see also Fig. 1, and the tray 12 is suspended by hangers 14 and supported by a pivoted bar 15. The member 17 comprises ends 18 pivoted to the framework at 20 and interconnected by bars 19 between which extend three columns 25 having slidably mounted thereon trunnion members 26, each tray 10, 11, 12 being connected to a respective one of the members 26 by a link 16. The ends 18 of the member 17 are connected by rods 24 to a pair of eccentrics 23 which are mounted on a shaft 22 driven by an electric motor 21. The members 26 are arranged so that at the lower end of their sliding travel on the columns 25 their pivot axes are in alignment with the axis 20 so that in this position no vibration will be transmitted to the trays 10, 11, 12. The positions of the members 26 on the columns 25 are individually controlled by three mechanisms each of which comprises a rod 27 pivoted to the associated link 16 and to one arm of a bell-crank lever 28 pivotally supported on the framework. The other arm of the lever 28 is connected by a rod (29), Fig. 4 (not shown), to a pneumatic ram 31 operated by valves which may be actuated by a weighing machine which the conveyer is feeding. The upper limit of the movement of each member 26 on the associated columns 25 is controlled by an adjustable stop member 33 against which a projection (34) on the lever 28 abuts as the ram 31 retracts the rod (29), the position of the member 33 being adjustable by means of a control knob 35. The conveyer may comprise a single tray and the rams 31 may be dispensed with, the projections (34) on the levers 28 being spring urged into engagement with the stop members 33.