Two way fixed fulcrum of bearing
One fulcrum is fixed in both directions, and the bearing other fulcrum swims
The left end is a fixed fulcrum, which bears two-way axial force; The right end is the traveling fulcrum, which only bears the radial force. When the bearing shaft is heated and extended, it can move axially.
For the fixed fulcrum, when the axial force is small, the deep groove ball bearing can be used, and the left and right sides of its outer ring are fixed. The upper part in the figure is fixed by the shoulder of the bearing seat hole. This structure makes the seat hole unable to be bored at one time, which affects the machining efficiency and coaxiality. When the axial force is small, the outer ring can be fixed with a circlip through the hole, as shown in the lower half of the figure. In order to bear the axial force to the right, the inner ring of the fixed fulcrum must also be fixed axially. For the floating fulcrum, deep groove ball bearings are often used, and cylindrical roller bearings can also be used when the radial force is large, as shown in the lower part of the figure. When the deep groove ball bearing is selected, there is a large gap between the outer ring of the bearing and the bearing cover, so that the shaft can extend freely during thermal expansion, but the inner ring needs to be fixed axially to prevent the bearing from loosening. When the floating fulcrum adopts cylindrical roller bearing, because its inner and outer rings can move axially relative, the inner and outer rings should be fixed axially to avoid excessive dislocation caused by the movement of the outer ring. During the design, it should be noted that the inner and outer rings of the bearing should not have redundant or insufficient bearing axial fixation.
