Cross-over bridge for ramps - has bridge pivotably mounted on ramp and fitted at free end with pivot extension

摘要

Drive over bridge for ramps includes a bridge plate pivotably mounted with its rear end on the ramp. Adjoining the free end of the bridge plate is an extension positioned vertically downwards when the drive over bridge is not used and which is in the plane of the bridge plate to support its free end when the drive over bridge is used on a loaded or off loaded platform. In the hinge position between the extension and the bridge plate stops limit the pivoting movement. One stop is in the plane of the bridge plate. The part of the extension which faces the bridge plate has its weight so determined that the centre of gravity of the extension is positioned between the bridge plate and axis of rotation when the extension is pivoted in the plane of the bridge plate. During pivoting of the extension from its vertical position in the plane of the bridge plate its centre of gravity is displaced over a top dead point. The extension (4) is fitted with a spring (17) which follows its pivoting movement and the displacement of the centre of gravity takes place at the same time as the following movement of the spring.