GB453980A - Improvements in or relating to gantry cranes - Google Patents

Abstract

453,980. Portable gantry cranes. ARDELTWERKE GES., Eberswalde, Germany. Nov. 6, 1935, No. 30698. Convention date, Sept. 26. [Class 78 (iv)] A gantry crane, capable of ready assembling, dismantling and transport, comprises a main girder or bridge a all in one piece, which is carried separately by a road or rail motor or trailer vehicle b, and four legs k detachably hinged at their upper ends to the girder and at their lower ends to trolleys n running upon the usual traversing track. All the parts other than the main girder are made in detachable pieces each of which can be lifted by one man. In the erection of the crane the main bridge is positioned across the track, the parts of the legs are assembled and the completed legs hinged to the girder. After assembling these parts, a hand or power-driven winch o is used to wind up tackle p to draw the pairs of legs at each end of the girder towards one another, thus elevating the girder. Metal ties secure the legs in the supporting position. To prevent the main girder tipping sideways, the angular movement of each leg k of a pair is equalized by inter-connecting the legs through toothed gearing q. Indicators may show the angle of each pair of legs with the horizontal to facilitate equal raising of opposite ends of the girder. When working, a loadcarrying trolley c runs to-and-fro on the main girder in the usual manner. When the main girder cannot be transported on its carriage all the way to the place of use, it may be transferred to a pair of endless-track tractors h to complete the journey. When carried in a railway truck, the bridge may be swung round on a turntable before it is transferred to the endless-track vehicles.