| 摘要 |
PROBLEM TO BE SOLVED: To provide a hole drilling bit that enhances ease of drilling, reduces costs, and curtails cutting time and reduces labor significantly, the hole drilling bit being compact and of a simple structure that enhances portability and ease of handling.SOLUTION: A hole drilling bit for a deck plate includes: one shaft part 2 having an upper member 2u on an upper side and a lower member 2d on a lower side, the upper member being held by a chuck part Hc of a power hammer H and the lower member having a protruded part 2ds formed at a lower edge; and a pair of right and left blade parts 3p, 3q formed integrally by plate members Pm, Pme having at least partially triangular surface parts 3ps, 3qs formed on the lower member 2d to protrude on both right and left sides of the lower member 2d, having protrusions 3pd, 3qd formed at a lower end and disposing the 3pd, 3qd at the lower end close to the protruded part 2ds of the lower member 2d, the triangular surface part becoming wider toward the upper side.SELECTED DRAWING: Figure 1 |
