GB937962A - Improvements in drive means for screens - Google Patents

Abstract

937,962. Screening apparatus. R. HALSTRICK. Jan. 24, 1961 [Jan. 25, 1960], No. 2729/61. Class 117. [Also in Group I] In a screen in which the screening surface is formed by bar elements, alternate ones of which are associated with one of two relatively-moving systems, of which systems at least one is driven, the screen elements of the driven system or systems are mounted on cross members driven by eccentrics. In Figs. 1 and 2, hollow cross members 1, 4 are associated with one system and similar members 2, 3 are associated with the other. Each of these members is driven by a pair of eccentrics housed within it (one at each end), and mounted on a shaft 25. The shafts are connected, and one is driven by a pulley 18. Cross members 1, 4 are connected by rigid or elastic longitudinal members 6, 6<SP>1</SP> and cross members 2, 3 by similar members 5, 5<SP>1</SP>. Further cross members 7, 7<SP>1</SP> are connected alternately to the two systems. On all cross members are placed further cross members 14 (see especially Fig. 1), which support flat bar-shaped elements transversely of them on edge. These elements together form a screen of the kind described in Specification 816,362. The elements have mutually interengaging projections on their vertical faces. In Fig. 10 (not shown) the hollow cross members each support a frame which is rectangular in elevation. The aligned upper parts of the frames carry one screen, and the aligned lower parts carry another screen. In Fig. 11 (not shown) the eccentrics rotate in downwardly extending fixing members for the screen elements, and in Fig. 12 (not shown) they rotate in the members 5, 6; in both cases the hollow cross members are dispensed with. In Fig. 14 a central tube 1 has rotating within it a pair of eccentrics mounted on a shaft 25<SP>1</SP>. The eccentrics appropriate to the other system are angularly displaced with respect to the first pair but are mounted on the same shaft and rotate within tubes 3, 4. The shaft 25<SP>1</SP> also carries out-of-balance weights 28 which impress a supplementary oscillation on the entire assembly. Fig. 15 shows diagrammatically two cross members 1, 2, each associated with one system, the ends of the longitudinal bars 5, 5<SP>1</SP>, 6, 61 being supported by elastic members 27, 27<SP>1</SP>. In Fig. 16 (not shown) the second system is driven indirectly by the first.