Abstract: Dental hand piece, comprising a housing and a drive train with a coupling element for a drive, wherein the housing radially surrounds the drive train and wherein the housing has a first and a second housing end, and wherein the housing is held on the drive train on the first and on the second housing end. Between the first housing end and the coupling element is arranged a decoupling element, which is strictly springy or springy and damping in the axial direction, whereas the second housing end is braced rigidly against the drive train and the housing is braced with respect to the coupling element in the axial direction by means of the decoupling element.

Abstract: The invention relates to a rotor (1) having a turbine wheel (3) driven by propellant (TG) in a turbine housing (2), a dental preparation instrument (20) having such a rotor (1) and a method (100) for operating such a preparation instrument (20), wherein at least one part of the propellant (TG) flows back to the gas outlet opening (51) in an inner wall (21) radially orbiting the turbine wheel (3) through a return flow channel (6) after impinging on at least one of the drive blades (31) of the turbine wheel (3) counter to the direction of rotation (DR) of the turbine wheel (3), the inner wall (21) in the segment of a circle (KS) comprises at least one return flow channel (6) extending at least from the gas inlet opening (41) as far as the gas outlet opening (51), which allows at least one part of the propellant (TG) to flow back to the gas outlet opening (51) through the return flow channel (6) after impinging on at least one of the drive blades (31) counter to the direction of rotation (DR) of the turbine whee

Abstract: A dental turbine driven by pressurized air comprises a head housing (1) with a turbine chamber (2) and a rotor shaft (3) mounted using an anti-friction bearing (8a) with a non-rotatably mounted turbine wheel (13). The outer race (10a) of the anti-friction bearing (8a) extends into the turbine chamber (2) in axial direction. The turbine wheel (13) comprises an annular web (16a) that is arranged concentrically to the outer race (10a) of the anti-friction bearing (8a) and, together with the outer race (10a), forms a gap seal (17a). This gap seal (17a) extends in axial direction between outer race (10a) and annular web (16a) and prevents the sucking-in of liquids and dirt particles into the turbine chamber (2) during inertial rotation of the turbine wheel (13).

Abstract: The invention relates to a clamping device for clamping a cylindrical instrument shank, in particular, a dental instrument, the clamping device including a spring-loaded element for holding the instrument shank, a hollow shaft for transmitting a rotational movement, and a plunger, with the spring-loaded element being designed as a sleeve with a cylindrical wall, a first opening and a second opening; and the wall having cut-outs. The spring-loaded element, the shaft and the plunger have axes of rotation that are arranged coaxially; the shaft protrudes at least partially into the first opening of the spring-loaded element; and the plunger protrudes at least partially into the second opening of the spring-loaded element.

Abstract: Dental hand piece, comprising a housing and a drive train with a coupling element for a drive, wherein the housing radially surrounds the drive train and wherein the housing has a first and a second housing end, and wherein the housing is held on the drive train on the first and on the second housing end. Between the first housing end and the coupling element is arranged a decoupling element, which is strictly springy or springy and damping in the axial direction, whereas the second housing end is braced rigidly against the drive train and the housing is braced with respect to the coupling element in the axial direction by means of the decoupling element.

Abstract: The invention relates to a clamping device (1) for clamping a cylindrical instrument shank, in particular, a dental instrument, said clamping device comprising a spring-loaded element (2) for holding the instrument shank, a hollow shaft (3) for transmitting a rotational movement, and a plunger, wherein the spring-loaded element (2) is designed as a sleeve with a cylindrical wall, a first opening (6) and a second opening (7); and the wall has cut-outs (8). The spring-loaded element (2), the shaft (3) and the plunger (4) have axes of rotation that are arranged coaxially; the shaft (3) protrudes at least partially into the first opening (6) of the spring-loaded element (2); and the plunger (4) protrudes at least partially into the second opening (7) of the spring-loaded element (2).