Improvements in or relating to trolleys of soaking pit cranes, ingot-stripping cranes and the like

摘要

810,639. Overhead travelling cranes. KONINKLIJKE NEDERLANDSCHE HOOGOVENS EN STAALFABRIEKEN N.V. April 3, 1957 [April 4, 1956], No. 10910/57. Class 78 (4). In an overhead crane, such as a soaking-pit crane, in which a tong column 3 (Fig. 1) suspended from a trolley 1 is held against movement relatively to the trolley in one or more horizontal directions, the wheels of the trolley are mounted in structures which normally engage abutments on the trolley but can move downwardly out of engagement with the abutments so as to remain in contact with the rails 8 when the trolley is tipped as a result of lateral forces on the tong column. In the construction illustrated, each of four wheels 2 (Fig. 4) at the corners of the trolley 1 is carried in a frame 14 pivoted about an axle 15 and normally engaging an abutment 24 which may be resilient. If, however, the trolley is tipped by a lateral load on the tongs 4 (Fig. 1) springs 22 hold the wheels 2 in engagement with their track. A dashpot 23 is effective only during upward movement of the wheels. The wheels 2 may be driven through a gear 19 on the shaft 15 from a gear 18 on a shaft 17 extending across the trolley. Switches controlling a warning signal or controlling the tong mechanism may be operated by undue movement of the wheel frames 14 which may slide vertically instead of being pivoted. The spring 22 and dashpot 23 may be replaced by an hydraulic system combining spring action and damping action and including a buffer space common to all the wheel mountings.