| 摘要 |
The device, essentially consisting of a guide sleeve (13), an eccentric bush (14) rotatably mounted therein and a drive shaft (15) rotatably mounted in the eccentric bush (14), for producing an undercut (1b) in a drilled hole (1a) in subsoil (1) has a housing (10, 12) supported on the subsoil (1) and surrounding the guide sleeve (13). Arranged between the housing (10, 12) and the guide sleeve (13) is a locking element (25) which permits rotation of the guide sleeve in the housing (10, 12) only in one direction of rotation. When the eccentric bush (14) is turned back, the guide sleeve (13) is prevented from turning with it by this locking element (25). …<IMAGE>… |
