Machine with thermally compensated bearings

Claim 2

A tapered roller bearing comprising a first race in the form of a cone having an outwardly presented tapered raceway and a back face located beyond the larger diameter end of the raceway; a second race in the form of a cup located around the cone and having an inwardly presented raceway and a back face at the smaller diameter end of the raceway, tapered rollers located in a single row between the raceways of the cup and cone, one of the races further having a backing surface that is presented in the same direction as its back face; and a compensating ring carried by said one of the races against the backing surface of that race, the ring being formed from a material having a high coefficient of thermal expansion.

Claim 3

A tapered roller bearing according to Claim 1 wherein the compensating ring is carried by the cup.

Claim 4

A tapered roller bearing according to Claim 2 wherein the cup contains a recess or groove which opens to its back face, the backing surface being at one end of the recess or groove, and wherein the ring is in the recess or groove.

Claim 5

A tapered roller bearing according to Claim 2 wherein the recess is a rabbet that opens out of the back face and outer surface of the cup.

Claim 6

A tapered roller bearing according to Claim 2 wherein the cup has a radially outwardly directed flange and the backing surface is on the flange.

Claim 7

A tapered roller bearing according to any one of Claims 1 to 5 wherein the compensating ring comprises an insert formed from a material having a high coefficient of thermal expansion and a harder backing element.

Claim 8

A tapered roller bearing according to Claim 6 wherein said material is an elastomer.

Claim 9

In combination with a case having abutments, a shaft in the case and also having abutments presented toward and spaced axially from the abutments of the case, the shaft being formed from a material which has a different coefficient of thermal expansion from the material of the case, and at least two bearings supporting the shaft in the case, said bearings being configured to accommodate both axial and radial loads and being mounted in the case and on the shaft between the abutments of the case and the shaft where they are in opposition to each other, so that the bearings confine the shaft both axially and radially in the case, the bearings having inner and outer races, each of which has an end face that is presented opposite to one of the abutments and each of which is further provided with a raceway that faces the raceway of the other race for its bearing, and rolling elements which roll along the raceways, a compensating ring located between the end face of one of the bearing races and the abutment toward which the end face of the race is presented, the compensating ring including an insert and first and second annular bands which together substantially encapsulate the insert, the insert being formed from a material having a coefficient of thermal expansion that is greater than the coefficients of thermal expansion for the materials from which the case and shaft are formed, the first and second bands together substantially confining the insert radially, but being capable of shifting axially relative to each other when the insert expands or contracts axially in response to temperature changes in the bearing, whereby the ring compensates for differential thermal expansion and contraction between the shaft and the case.

Claim 10

In combination with a case having abutments, a shaft in the case and also having abutments presented toward and spaced axially from the abutments of the case, the shaft being formed from a material which has a different coefficient of thermal expansion from the material of the case, and at least two bearings supporting the shaft in the case, said bearings being configured to accommodate both axial and radial loads and being mounted in the case and on the shaft between the abutments of the case and the shaft where they are in opposition to each other, so that the bearings confine the shaft both axially and radially in the case, the bearings having inner and outer races, each of which has an end face that is presented opposite to one of the abutments and each of which is further provided with a raceway that faces the raceway of the other race for its bearing, and rolling elements which roll along the raceways, a compensating ring located between the end face of one of the bearing races and the abutment toward which the end face of the race is presented, the compensating ring including an insert and first and second annular bands which together substantially encapsulate the insert, the insert being formed from a material having a coefficient of thermal expansion that is greater than the coefficients of thermal expansion for the materials from which the case and shaft are formed, the first and second bands together substantially confining the insert radially, but being capable of shifting axially relative to each other when the insert expands or contracts axially in response to temperature changes in the bearing, whereby the ring compensates for differential thermal expansion and contraction between the shaft and the case.

Claim 11

The combination according to Claim 8 wherein the first band fits within the second band such that the two bands will telescope with respect to each other when the insert expands.

Claim 12

In combination with a case having abutments, a shaft in the case and also having abutments presented toward and spaced axially from the abutments of the case, the shaft being formed from a material which has a different coefficient of thermal expansion from the material of the case, and at least two bearings supporting the shaft in the case, the bearings being configured to accommodate both axial and radial loads and being mounted in the case and on the shaft between the abutments of the case and the shaft where they are in opposition to each other, so that the bearings confine the shaft both axially and radially in the case, the bearings having inner and outer races each of which is presented opposite to one of the abutments and is provided with a raceway that faces the raceway of the other race for the bearing, and rolling elements which roll along the raceways, one of the races of at least one of the bearings having a recess which opens toward the abutment opposite which that race is presented and compensating means located in the recess and against the abutment to which the recess opens for responding to temperature changes in the bearing, thereby to compensate for differential thermal expansion and contraction between the shaft and the case.

Claim 13

In combination with a case having abutments, a shaft in the case and also having abutments presented toward and spaced axially from the abutments of the case, the shaft being formed from a material which has a different coefficient of thermal expansion from the material of the case, and at least two bearings supporting the shaft in the case, the bearings being configured to accommodate both axial and radial loads and being mounted in the case and on the shaft between the abutments of the case and the shaft where they are in opposition to each other, so that the bearings confine the shaft both axially and radially in the case, the bearings having inner and outer races each of which is presented opposite to one of the abutments and is provided with a raceway that faces the raceway of the other race for the bearing, and rolling elements which roll along the raceways, one of the races of at least one of the bearings having a recess which opens toward the abutment opposite which that race is presented and compensating means located in the recess and against the abutment to which the recess opens for responding to temperature changes in the bearing, thereby to compensate for differential thermal expansion and contraction between the shaft and the case.

Claim 14

The combination according to Claim 10 wherein the compensating means includes a flexible material that is rigidly and snugly confined radially in the recess so that the material is prevented from expanding radially inwardly or outwardly, whereby volumetric expansion and contraction manifests itself only in the axial direction.

Claim 15

The combination according to Claim 10 wherein the compensating means comprises a ring of a flexible material confined between two annular bands which are in axial telescoping engagement with each other.

Claim 16

The combination according to Claim 11 or Claim 12 wherein said flexible material is an elastomer which is substantially incompressible.

Claim 17

The combination according to any one of Claims 10 to 13 wherein the bearing is a tapered roller bearing, said recess being formed in the back face at the small diameter end of the tapered raceway of the outer race of the bearing and the compensating means fitting into the recess.

Claim 18

The combination according to Claim 14 wherein the recess is a rabbet which opens out of the cylindrical outer surface and the back face of said outer race.