EXPANDABLE HAMMER

摘要

PURPOSE: An expansion hammer is provided to partially extend the radius of excavation through stepwise excavation and freely regulate the extended radius of excavation. CONSTITUTION: An expansion hammer comprises a hammer body(100), air hammers(200), a hydraulic cylinder, and an ascending and descending block(400). The hammer body, whose top is connected to a connecting bar, has side openings(110) at regular intervals. The air hammers, whose top is pinned on the hammer body and bottom is equipped with a hammer bit(220), are accommodated in the respective openings with the lower side open outward. The hydraulic cylinder is installed on the upper central part of the hammer body. The ascending and descending block is coupled to the bottom of the piston rod of the hydraulic cylinder and ascends and descends in contact with the air hammers according to the operation of the hydraulic cylinder.