UNDERGROUND EXCAVATOR

摘要

An underground excavator is formed by providing a crank to a rotary driver of cutter section, coupling a plurality of hydraulic jacks to the crank as mutually spaced in circumferential direction, and rotatively driving the rotary driver by means of these hydraulic jacks through the crank. Cutter drive section is thereby simplified remarkably in the structure, and the cutter section can be rotatively driven without requiring any parts high in the working precision or any lubricating oil.