| 摘要 |
The present invention relates to a percussion drill bit (1) for directional drilling tools (10). The drill bit comprises a head portion (2) formed with an axially extending shank (3). The drill bit also comprises engagement means (4) on the shank engageable with complementary engagement means formed on a drive chuck whereby rotational drive from the chuck may be transmitted to the shank. The head portion (2) of the drill bit is formed with a plurality of slant faces (5) arranged symmetrically about the head portion. |
