(EN) Disclosed is a dentists' preparation instrument (1) comprising a turbine (4) for driving a tool (3) using compressed air, and a rotor (6) that is arranged in a turbine compartment (5), rotates about a longitudinal axis (7), and has blades (11) extending to a face (13) of the rotor (6). The turbine compartment (5) has a wall (10) opposite the face (13), and a discharge port (12) for the compressed air in the direction of a returning air duct (8). The discharge port (12) is disposed in such a way that at leasts parts of the blades (11) swipe past the discharge port (12) as they rotate about the longitudinal axis (7). The turbine compartment (5) also has a disruptive contour chamber (15) that adjoins the face (13). The face (13) of the blades (11) of the rotor (6) that faces the disruptive contour chamber is open towards the disruptive contour chamber (15). Inside the disruptive contour chamber (15), a disruptive contour (9) is formed on the wall (10) opposite the face (13) by at least one projection (14) extending along a height (h) in the direction of the longitudinal axis (7).
(ZH) 一种牙科处理仪器(1),其具有借助压缩空气来驱动工具(3)的涡轮机(4),所述处理仪器包含设置在涡轮机腔室(5)中的且围绕着纵轴线(7)旋转的转子(6),所述转子具有一直延伸至所述转子(6)端侧(13)的叶片(11)。所述涡轮机腔室(5)具有与所述端侧(13)相对而置的壁板(10),并且具有朝向回风通道(8)的压缩空气排出孔(12),其中所述排出孔(12)在设置时,要使得至少所述叶片(11)的部分在围绕着所述纵轴线(7)旋转时从所述排出孔(12)的旁边掠过。所述涡轮机腔室(5)还具有与所述端侧(13)相邻的干扰轮廓空间(15),其中所述转子(6)的所述叶片(11)面向所述干扰轮廓空间的所述端侧(13)朝所述干扰轮廓空间(15)是敞开的,并且在所述干扰轮廓空间(15)中设置有干扰轮廓(9),所述干扰轮廓由至少一个沿所述纵轴线(7)方向在高度h上延伸的隆起(14)构成,并设置在与所述端侧(13)相对而置的壁板(10)上。