Abstract: To produce an inexpensive small size ball bearing, the inner ring races are formed of spherical segments which are connected to each other at flattened connection places. A row of balls is guided by a respective inner ring race contact point on each of the segments in the region of the attachment place between two segments. In a four point ball bearing, the single row of balls contacts two contact points, one on each spherical segment, that define the inner race and contacts two races formed in the outer ring. In a three point bearing, there are two axially spaced apart rows of balls and three spherical segments in an axial row, two of the spherical segments of the inner ring define two of the inner race contact points for one of the ball rows and two other spherical segments of the inner ring defined two of the inner race contact points for the other row of balls. In both embodiments, the outer ring is split into two parts, each having one contact point on it.

Abstract: A high precision, two-row ball bearing wherein the inner races of the two rows are worked into the shaft and there are respective outer rings around the rows of balls. A spacer bushing is axially disposed between the outer rings. The spacer bushing is of a single piece with an axial slot extending along its length. The slot has a width approximately equal to the diameter of the shaft. The center of the diameter of the bore of the spacer bushing is offset from the center point of the diameter of the external periphery of the spacer bushing, whereby the spacer bushing is radially thinnest opposite the axial slot and thickens toward the slot for balancing the mass of the spacer bushing with the material removed from the slot. A housing bushing surrounds the spacer bushing and the outer rings.