GB819981A - Improvements in or relating to overhead travelling cranes - Google Patents

Abstract

819,981. Overhead travelling cranes. ELECTRICITE DE FRANCE. May 14, 1957 [May 15, 1956], No. 15342/57. Class 78 (4). The tracks 4 supporting the bridge 6 (Fig. 1) of a bridge crane in an underground chamber are supported from the imposts 3 of the arched roof 1, and the .bridge 6 is underslung so that the track B for the crab 7 is below the tracks 4: this permits the hook 9 to approach more closely to the walls 2. The brackets 6a supporting the bridge from wheels 8 may be replaced as shown in Fig. 3 by brackets 10 pivoted at 12 to the bridge 6 and carrying rollers 14 engaging tracks 16 on the walls. Further tracks 15 and rollers 13 engaging them and carried by the bridge 6 are omitted in an alternative embodiment in which the brackets 10 at opposite sides of the bridge are connected at their lower ends by a tie rod. In an alternative construction the brackets 10 are cranked so that the pivots 12 lie vertically beneath the tracks 4 and the rollers 14 and tracks 16 are then omitted. Two spaced girders 6a, 6b (Fig. 7) forming the bridge may be pivoted at 27 to equalizing beams 26 on which they are suspended through pivots 25 from further equalizing beams 24 suspended on hangers 10a ... 10d each supported by a wheel 8a ... 8b from the track 4. The hangers 10a ... 10d are joined in pairs by covers 29 which are connected by links 31. The tracks 4 may be carried by shoulders on the abutments of the arch as in Figs. 1 and 3 or alternatively two tracks 40 (Fig. 8) may be carried by a beam 41 suspended through bars or wires 42 at each end of the arch. The equalizer bars 26, 24 (Fig. 7) may be of I- section or, as shown in (Fig. 8), they may be of channel section, the smaller bars nesting within the larger.