Improvements in or relating to vibrating unit for screens and similar vibratory structures

摘要

639,842. Jigging-conveyers. NORDBERG MANUFACTURING CO. March 31, 1947, No. 8618. Convention date, Aug. 4, 1944. [Class 78 (i)] [Also in Group XXIV] The invention relates to units of the unbalanced rotor type for vibrating sifting screens and similar vibratory structures and having a weight mounted thereon which is normally held in fixed position relative to the rotor by yieldable means in which position the rotor is substantially balanced until a predetermined speed of rotation is attained at or above which the weight moves radially outwards to produce unbalance of the rotor and cause vibration of the apparatus. According to the invention resilient snubbing means are associated with the rotor and are adapted to cushion the shock resulting from the stoppage of the weight as it reaches its outer limit of movement. As shown, weight 32 is held in normal position by springs 35 compressed between head 36 and the interior face of the portion 12 of the rotor. Head 36 is adjustable on a bolt 37. Shock-absorbing washers 41 and 45 are provided between the weight and the shaft portion 12 and a snubber spring 43 is interposed between the lower wall of portion 12 and the head 36. At a predetermined high speed of the rotor, the weight 32 moves radially outwards between guides and when washer 41 contacts portion 12, the spring 43 contacts collar 44 on head 36 to cushion the impact of the head 36 with portion 12. The portion 12 connects together two end portions 10, 11 of a shaft having bearings 7, 8, 9, the outer dust-proof housings 4 of which are secured by bolts 6 to transverse channel members 3 joined edge to edge and connecting the longitudinal side members 2 of the screen. The shaft is coupled to a driving pulley 25 by flexible couplings 19,21. The Specification as open to inspection under Sect. 91 comprises also an unbalancing system, Fig. 6 (Cancelled) and Fig. 7 (Cancelled), comprising a square portion 75 of rotor shaft having a central member 76 (Fig. 6, Cancelled) secured thereto and a movable member consisting of piece 87 and two side pieces 86 running the length of the square portion and two other pieces 88 one on each side of piece 76 and spaced from pieces 86 by spacing members 89. The pieces 86, 87, 88 are secured together by nuts and bolts 90 or members 86 and 87 may be one piece secured to pieces 88 by bolts 90. When a predetermined speed of rotation is attained by the shaft the combination 86, 87, 88 moves relatively to the shaft, i.e. upwardly in the drawing, compressing springs 83 disposed in pockets in members 86, the amount of movement 89a (Fig. 7, Cancelled) being limited by spacers 89. This subject-matter does not appear in the Specification as accepted.