| 摘要 |
A rotary percussive tool, comprising a casing 1 has a drive with a drive gear 11, a bushing 12 having a non- round hole 13 for insertion of a shank of a boring tool 7 and a protective clutch 22, 23 mounted thereon and meshing with the drive gear to limit torque on the boring tool. The tool has a driven gear 15 which is mounted on the bushing 12 for independent rotation and meshes with the drive gear 11. The driven gear has a hole 20 for insertion of a drilling tool, and provides drilling tool rotation without torque limiting. The boring tool shank 14 is engaged by a reciprocating member 5 actuated by a piston 3. A tool for impelling only has a round shank to avoid rotation with the sleeve 12. <IMAGE> |
