Expansion excavating device for circular pile

摘要

The present invention provides an expansion excavation device for circular pipe excavation which facilitates penetration of a thick concrete pile, simplifies an expansion wing slid by a centrifugal force and a force pushing the ground to facilitate manufacture, effectively allows a sliding motion of an expansion wing, sequentially widens expansion areas, and distributes excavation power to a plurality of expansion wings to reduce a possibility of damage to expansion wings. According to a proper embodiment of the present invention, the expansion excavation device comprises: an excavation shaft having a rotation operation unit coupled to a drill shaft of auger equipment during ground penetration of a circular pipe, and a wing shaft unit concentrically integrated into the rotation operation unit and chamfered into a rectangular cross section; a pair of helical transport wings having a phase of 180 degrees on a circumference of the shaft unit and rotating in the same helical direction to transport excavated soil upwards; a pair of lower expansion wings which have a prescribed radius of rotation by allowing one end thereof to be pivot-connected to a lower portion of the wing shaft unit by a lower pivot shaft forming a right angle with respect to the excavation shaft, and are installed at positions of 180 degrees to perform expansion excavation; and a lower expansion wing rotation inducing wheel rotatably connected to the other end of the lower expansion wings by a lower wheel shaft having a direction parallel with the lower pivot shaft.