US 6,490,935 B1 · System for monitoring the operating conditions of a bearing

Abstract

A tapered roller bearing has at least one groove in its fixed race, with that groove being located behind and presented away from the raceway for the race. The groove, which creates an unsupported beam within the race, contains a strain sensor which is oriented to detect strains in the circumferential direction. The presence of a loaded roller over the beam deflects the beam and causes the sensor to produce a signal, with the magnitude of the signal reflecting the magnitude of the load transmitted by the roller. By locating one sensor where the greatest radial load is transmitted and two sensors 30° to 70° symmetrically on each side of that one sensor, one can measure both radial and axial loads in the bearing. By locating two sensors in a single groove, axially aligned, but also axially offset, one can detect misalignment of the raceways along which the rollers roll and also skewing of the rollers. By locating one sensor 90° from the location of the greatest radial load, one can measure the axial load in the bearing. An arrangement similar to the foregoing may also be used to ascertain the torque transmitted by a shaft supported on the bearing.

Claims17

Dependent claims

An antifriction bearing for accommodating rotation about an axis while transmitting a load that is directed at an angle with respect to the axis, said bearing comprising:

an inner race having a tapered raceway presented outwardly away from the axis;
an outer race having a tapered raceway presented inwardly toward the raceway of the inner race;
tapered rollers located between the races and contacting the raceways, whereby the rollers will roll along the raceways when relative rotation occurs between the races;
one of the races having a first groove located directly behind the raceway of that race and generally aligned with the load, said one race also having a second groove located directly behind the raceway of that race and located between 30° and 70° from the first groove, the grooves extending axially in said one race and forming unsupported beams in said one race;
and a first strain sensor attached to said one race in the first groove and a second strain sensor attached to said one race in the second groove, the sensors being capable of detecting strains in the beams of said one race and being oriented to detect strains in the circumferential direction.

2 more elements

A process for ascertaining the distribution of forces in a tapered roller bearing as a consequence of a load applied to and transferred by the bearing, said bearing facilitating rotation about an axis and having inner and outer races provided with opposed raceways and tapered rollers organized in a row between the raceways, so that the rollers will roll along the raceways when relative rotation occurs between the races, whereby the rollers will produce cyclic strains in the races, said process comprising:

measuring strain in the circumferential direction on one of the races behind the raceway for that race at a location generally aligned with the load;
measuring strain in the circumferential direction in the same race at a location that is offset between 30° and 70° in one circumferential direction from the load, and comparing the strains measured at the locations to ascertain the distribution of forces in the bearings.

Dependencies are inferred from the claim text.

System for monitoring the operating conditions of a bearing

Life of this patent

System for monitoring the operating conditions of a bearing

Life of this patent

Abstract

Claims17