END WIDTH INCREASING EXCAVATOR OF EARTH DRILL AND ENLARGED BOTTOM PILE CONSTRUCTION METHOD USING THE EXCAVATOR

摘要

PROBLEM TO BE SOLVED: To provide an end width increasing excavator of an earth drill capable of increasing the diameter of the enlarged bottom part of a cast-in-place concrete pile by increasing the enlarging angle of a width enlarging blade. SOLUTION: In this end width increasing excavator of an earth drill, the enlarging blade 2 forming a part of the outer shell of a cylindrical bucket 1 is so pivotally supported as to be radially opened and closed through a hinge 3. The enlarging blade 2 is connected to a slide frame 4 moving in the axial direction inside the bucket 1 through a link rod 5. The enlarging blade 2 is opened and closed by the lifting operation of the slide frame 4. A lateral shaft 6 for supporting the vertical swing of the link rod 5 is installed in the slide frame 4, and a vertical shaft 7 for supporting the lateral swing of the link rod 5 is fitted to the lateral shaft 6. The lateral shaft 6 and its bearing part 8 are so installed as to be tilted from the normal direction of the bucket 1 to the hinge 3 side of the enlarging blade 2. COPYRIGHT: (C)2008,JPO&INPIT