| 摘要 |
PROBLEM TO BE SOLVED: To enable the high-speed rotation while restricting the inclination by forming the curvature radius of a track surface cross section of one of an inner and an outer rings into a Gothic arch shape symmetrical to the center surface, and forming that of the other into the single curvature so as to form a three-point contact, and specifying the curvature radius and center position of the curvature. SOLUTION: An inner and an outer rings 2, 3 of a bearing 1 are unified, and a curvature radius of a cross section of a raceway surface 4 of the inner ring 2 is formed into Gothic arch shape symmetrical to the center surface 6b passing through the center 6a of a bottom part of the raceway surface, and cross section of a raceway surface 5 of the outer ring 3 is formed with a single curvature so as to form a single raw ball bearing having three-point contact. The curvature radius of one raceway surface is formed at 51-55% of the dimension of a steel ball 8, and the centers of the curvature are respectively arranged so as to cross each other at the same distance in the radial direction of the bearing, and at 0.8-5.7% of the dimension of the steel ball 8 in symmetry to the center surface 6b in the axial direction. Angle of contact of the steel ball 8 with the outer ring 3 or the steel ball 8 with the inner ring 2 is set at 15-35 degree, and cross section of the raceway surface of the single curvature side is formed with the single curvature at 50.5-56% of the dimension of the steel ball 8. The raceway surface 4 and the steel ball 8 contact with each other to three points, and the inclination in relation to the bending moment is reduced, and the seizure is reduced. |
