Method and apparatus for excavating a subterranean drainage channel

摘要

An apparatus comprise an excavator, able to be pulled by a tractor 10, having an endless chain 24 with excavating buckets 25 attached, a reformer knife 31 to form a slit space, a pressing member 32 attached to the reformer knife, which scrapes earth from the sidewalls of the slit space and forces the earth backwards through a narrow gap to close the slit space and create an enclosed subterranean drainage channel, S. The excavated earth H(T), is transported to a discard section where it is scattered from the rear of the excavator in order to fill the upper part of the slit space. A control system incorporates laser guidance apparatus 51, to move the excavator up or down, allowing the excavator to be used to form inclined drainage channels.