| 摘要 |
A tool (1), normally a drill, has a cylindrical shank (2) for insertion in a tool holder of a rotary percussive or a rotary machine. The shank (2) has two diametrically opposing flat surfaces (3) and two adjoining ridges with radially extending surfaces (5). The surfaces (5) are on the same diameter. <??>At 90 DEG to the flats (3) there are two circular surfaces (9). <??>The flat surfaces (3) provide a bearing for cooperation with an elongate driving member of the tool holder. The circular surfaces (9) are engaged by spring loaded balls (10) to retain the tool in the holder. <??>An alternative realisation of the tool uses intact keyways instead of the flat surfaces (3) and the radial surfaces (5), trapezoidal keyways (14, 15, 16) that have not one shoulder cut away. |
