To provide an earth drill making it possible to easily select either earth drill work or hammer grab work, depending on whether the ground is weak or hard, for the discharge of sediment in a easing used in all-casing construction method.
The earth drill is an excavator for excavating a pile hole for a cast-in-place pile. In the earth drill, a boom 2 that can be raised and lowered is provided with a front frame 17 carrying a Kelley's bar drive 22 and a Kelley's bar 5 with an excavating bucket 20 mounted at its lower end is suspended by a winch driven by a hydraulic motor provided on a base machine 1. Another winch for suspending a hammer grab 25 or a hammer crown 26 is added to the base machine 1 and the hammer grab is suspended by still another winch which is different from the winch suspending the Kelley's bar 5. The winch for suspending the hammer grab or the hammer crown is used for hoisting a reinforcing cage or the like during the earth drill work.
TOMITA YASUKIMI
YOSHIDA SHIGEMITSU
KIKUCHI SHIGENORI
