Trench excavating and shoring apparatus

摘要

A ditch-digging or trenching machine has a plurality of wall-engaging spreadable and retractable members which can be received in the trench to be advanced and provided with respective fluid-powered cylinders connectible to a cutting head for advancing the latter and drawing the retracted wall-engaging members thereafter to cut the trench. The cutter head includes a milling-type cutter in the form of a worm conveyor adapted to convey the detritus from the trench.