RECOVERY-TYPE DRILLING BIT FOR SUPPORTING TUNNEL

摘要

The present invention relates to a recovery-type boring bit for tunnel reinforcement, capable of easily collecting a boring bit by boring a reinforcement duct to be matched with the external diameter of a reinforcement pipe while reducing the external diameter of the boring bit to be matched with the internal diameter of the reinforcement duct after the completion of boring work in order to bore the reinforcement duct to insert the reinforcement pipe along an outer edge of a tunnel. According to the present invention, since a shaft is combined with a main bit by a bit connector, the main bit is rotated through normal rotation while reversing is allowed through reverse rotation to tow the main bit, thereby simplifying a combination structure. The present invention includes: a shaft providing an impact and rotational force; and a bit connector.