When the compressed air is not applied, an inclined surface, which is positioned at an upstream side with respect to the supply direction of the compressed air, of the lip part is in contact with the inclined surface of the inner ring. When the compressed air is applied, a contact area between the inclined surface, which is positioned at the upstream side with respect to the supply direction of the compressed air, of the lip part and the inclined surface of the inner ring becomes smaller, as compared to when the compressed air is not applied.

When the compressed air is not applied, an inclined surface, which is positioned at an upstream side with respect to the supply direction of the compressed air, of the lip part is in contact with the inclined surface of the inner ring. When the compressed air is applied, a contact area between the inclined surface, which is positioned at the upstream side with respect to the supply direction of the compressed air, of the lip part and the inclined surface of the inner ring becomes smaller, as compared to when the compressed air is not applied.

The dental handpiece consists of a housing with a handle and a turbine that can be operated with compressed gas or compressed air. The rotational movement of the turbine driven by compressed gas is transmitted to the dental tool via a rotor shaft and a chuck. The rotor shaft is rotatably supported by at least one axial groove ball bearing. The radial rigidity required for operating a dental handpiece is achieved by axially preloading the ball bearings. Projections on the housing and the shaft disc of the at least one axial groove ball bearing allow the axial groove ball bearing to be used as radial groove ball bearings. The proposed design of the dental handpiece exhibits little power loss or frictional loss in comparison to dental handpieces with radial groove ball bearings, and slip and drilling friction components can be virtually completely prevented in particular.

The disclosure relates to a head bearing assembly for a dental or surgical handpiece, comprising an outer sleeve, in which at least four radial bearings are arranged, which enclose an axis of rotation and each have their own bearing outer ring or a common bearing outer rings, wherein the bearing outer rings are surrounded radially on the outside by the outer sleeve in the circumferential direction about the axis of rotation, and each radial bearing has at least one or exactly one rolling element row with rolling elements which are arranged one behind the other in the circumferential direction and rolling in the respective bearing outer ring.

The head bearing assembly according to the disclosure is characterized in that the at least four radial bearings have a common, integral bearing inner ring on which the rolling elements are arranged in rolling contact.

Provided is an adapter for connection to a spray can dispensing an oil-containing aerosol. The adapter comprises a timepiece configured to measure a predetermined time interval, the starting point of the time measurement being defined by the start of a spraying process of the spray can; and an indicating element configured to indicate to the user, once the predetermined time interval has expired, to end the spraying process. Also provided is a method for manually reprocessing a medical device.

The present invention relates to a cutting device (1) for surgical or dental use, comprising a motor (10) connected to a handpiece (4) provided with a transmission module (2) for a cutting tool (3), the transmission module (2) comprising: a motor coupling part arranged to be set in rotation by the said motor (10); a kinematic chain transforming the rotary movement of the motor (10) into a first linear reciprocating movement (M1) of a blade holder (27) via a rotary transmission shaft (22) provided with an eccentric (23),

the transmission module (2) being characterized in that it further comprises a counter-mass (5) arranged so as to move according to a second linear reciprocating movement (M2) synchronized with the first linear reciprocating movement (M1) of the blade holder (27), and in the opposite direction to the latter.

When compressed air does not act, a seal member is in contact with an outer periphery of an inner ring. When the compressed air acts, a contact area between the seal member and the outer periphery of the inner ring is reduced, as compared to when the compressed air does not act. Accordingly, it is possible to provide an air turbine bearing unit capable of promptly stopping rotation.

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).

The present invention relates to a transmission rotor for a handpiece (1) suitable to dental or chirurgical applications, comprising a device for clamping a drilling tool (100), able to be actuated in rotation about an axis of rotation (R) by means of a drive mechanism which comprises a drive shaft (2) rotatable about the said axis of rotation (R).

The clamping device comprises a clamp (4) disposed inside the drive shaft (2) for axially securing the drilling tool (100) with respect to the axis of rotation (R), the clamp (4) co-operating with a plunger (5) for releasing the drilling tool (100), as well as a radial guide bush (3) of the drilling tool, rotating integrally with the drive shaft (2), and wherein it comprises a selective angular coupling mechanism (C.sub.s) between the clamp (4) and the guide bush (3) or the drive shaft (2) directly, according to the chosen preferred embodiment; the selective angular coupling mechanism (C.sub.s) exerting an angular holding torque (C) between the clamp (4) and the guide bush (3) or respectively the drive shaft (2), the value of which being inferior to that corresponding to the slip threshold between the said clamp (4) and the drilling tool (100).

Provided is a roller bearing in which a restraining force of a seal member is further strengthened. The roller bearing includes: an outer ring having an outer ring raceway surface on an inner peripheral surface; an inner ring having an inner ring raceway surface on an outer peripheral surface; a plurality of rolling elements rotatably arranged between the outer ring raceway surface and the inner ring raceway surface; and a seal member that is fixed to a seal attachment groove formed in an axially end portion of the outer ring by a snap ring and seals an axially end portion of a bearing internal space between the outer ring and the inner ring, in which an outer diameter of the seal member is larger than an outer diameter of the snap ring in the seal attachment groove, and in which a radially outer end portion of the seal member is sandwiched between an inner peripheral surface of the seal attachment groove and an outer peripheral surface of the snap ring.