Machine placing pylon in hole - has vehicle mounted derrick with extensible horizontal beam guiding pylon home

摘要

The machine places a post or pylon in an excavated hole, being particularly for installing overhead electric power lines. It comprises a derrick with winch, mounted on a vehicle, and equipped with a hoist block, manoeuvring the pylon into a roughly vertical position above the hole. A horizontal beam has an extensible portion acting as a guide, and thrusting against the pylon as it is lowered into the hole. When it has the bottom, this portion pulls it into the vertical position. The derrick can comprise telescopic components, folding on a frame into a travelling position above the vehicle when locking devices holding it in the vertical working position have been retracted.