Head bearing assembly for a dental or surgical handpiece and dental or surgical handpiece comprising such a head bearing assembly

Head bearing assembly for a dental or surgical handpiece, comprising an outer sleeve, in which at least four radial bearings are arranged, the at least four radial bearings enclose an axis of rotation and each of the at least four radial bearings has its own bearing outer ring or any two radial bearings of the at least four radial bearings share a common bearing outer rings, wherein

• the bearing outer rings are surrounded radially on the outside of the outer sleeve in the circumferential direction about the axis of rotation,
• 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;
• and
• wherein each of the bearing outer rings are axially pretensioned against each other and each of the bearing outer rings are moveable independently from each other;
• wherein the at least four radial bearings have a common, integral bearing inner ring on which the rolling elements are arranged in rolling contact.