Shank for a rotary percussion tool

摘要

The insertion end (2) has at least two adjacent recesses (5) outside the main radial measurement (R) with at least one projection (6) between them. In cross section through the axis (A), the radial measurement of the recesses totals a central recess angle of less than 150 degrees. The total difference between the angles of a projection and the recesses is at least 15 degrees.