OPENING METHOD FOR CONCRETE AND CORE DRILL THEREOF

摘要

PURPOSE:To cool a core drill and to enhance the cooling efficiency of cutting chips by discharging compressed air cutting chips from the discharge hole on the outer periphery of a cylinder by a large discharging force to form an air loop. CONSTITUTION:A drilling is started while confirming a drilling position from the outside of a core drill 10 upon rotation of the drill 10. Compressed air P is fed from a compressor 4 though a hole 7 and a through hole 11 of a shaft 12 upon drilling, and injected from the hole 11 of a cylinder 14. Accordingly, cutting chips 5 are cooled with the air P, and concrete cutting chips R at the time of drilling of concrete are blown out. Since an agitating stream is generated at the top of a cylinder inside 17 in a negative pressure state, the chips R and the air P are discharged from a discharge hole 16 to a cover member 20 while being agitated.