Figure 1 The relationship between axial clearance and angular clearance 33 series 52 series 53 series 32 series radial clearance Angular clearance Similarly, the angular clearance of a double-row bearing also refers to the maximum angle at which one of the inner and outer rings is fixed, and the other is not fixed. Since it can be tilted from the center position to the left and right, the angular clearance is the limit tilt angle of the inner and outer rings: axial clearance (mm) degrees (under the premise that no torque is generated, the inner and outer rings may be inclined to one side from the center position Maximum angle) 2 times. The relationship between radial clearance and angular clearance of double row angular contact ball bearings is shown in equation (1). The relationship between radial clearance and axial clearance of double row angular contact ball bearings is as described in B111. Using this relationship, the relationship shown in Figure 1 is converted into the relationship between the angular clearance θ and the radial clearance Δr, that is, the content shown in Figure 2 is obtained. The 52, 53 series and 32, 33 series of double row angular contact ball bearings are shown in Fig. 1 according to formula (1). Δau003d2m sin 0＋ Ri － 1－( ＋)2(1)2m0 axial clearance ΔaΔr.