Bearing assembly with overload protection
A bearing assembly is described that includes a shaft and an inner race affixed to the shaft. An outer race is disposed radially around the inner race defining a bearing run space with rolling elements between the inner and outer races. An axial bore in the support or the rotor has a radial gap between the bore wall and the outer race, and the assembly is configured to provide a radial displacement between a portion of the outer race and the axial bore wall in response to a radial overload force applied to the rotor.
1. A bearing assembly for providing engagement of a rotor and a support, comprising:
a shaft;
an inner race affixed to the shaft;
an outer race disposed radially around the inner race, the inner and outer races together defining a bearing run space between the inner and outer races; and
rolling elements in the bearing run space;
wherein one of: (i) the shaft along with the inner race or (ii) the outer race, is attached to and configured to rotate with the rotor, and the other of (i) the shaft along with the inner race or (ii) the outer race, is attached to the support;
a first axial bore that is in the rotor if the outer race is the rotor or is in the support if the outer race is attached to the support;
a second axial bore that is in the support if the outer race is attached to the rotor or is in the rotor if the outer race is attached to the support; and
wherein a first portion of the outer race is disposed in the first axial bore, and a second portion of the outer race is disposed in the second axial bore with a radial gap between a wall of the second axial bore and the second portion of the outer race; and
further wherein the assembly is configured to provide a radial displacement between the second portion of the outer race and the second axial bore wall in response to a radial overload force applied to the rotor.
2. The assembly of claim 1 , further comprising a compliant bushing engaged with the shaft to provide said radial displacement.
3. The assembly of claim 1 , wherein the shaft has flexibility to provide said radial displacement.
4. The assembly of claim 1 , wherein at least a portion the rolling elements extends axially from the first or second axial bore that is in the support.
5. The assembly of claim 4 , wherein the rolling elements have an axial center line that is outside of the first or second axial bore that is in the support.
6. The assembly of claim 1 , wherein the outer race has an axial center line that is outside of the first or second axial bore that is in the support.
7. The assembly of claim 1 , wherein the shaft along with the inner race is attached to and configured to rotate with the rotor.
8. The assembly of claim 1 , wherein the outer race is attached to and configured to rotate with the rotor.
9. The assembly of claim 8 , further comprising a cooperating member that is axially displaceable in response to radial displacement of the shaft.
10. The assembly of claim 9 , wherein the shaft includes a first engagement surface at an angle between the radial and axial directions, and the cooperating member includes a second engagement surface.
11. The assembly of claim 10 , further comprising a biasing element against axial displacement of the cooperating member.
12. The assembly of claim 9 , further comprising a biasing element against axial displacement of the cooperating member.
13. A method of using the assembly of claim 1 , comprising
applying a radial load to the rotor, thereby causing radial displacement of the rotor up to a point of contact of the outer race with the axial bore wall; and
transferring the radial load from the rotor through the outer race to the axial bore wall in contact with the outer race.