Patent ID: 7320257

Claim:
A load measuring device for a rolling bearing unit comprising: a stationary ring having two rows of raceways; a rotating ring arranged concentrically with the stationary ring, the rotating ring having two rows of raceways which are formed respectively to be opposite to the raceways of the stationary ring; a plurality of rolling elements provided rotatably between the raceways of the stationary ring and the rotating ring, wherein contact angles of the rolling elements are directed mutually oppositely between a pair of raceways formed on the stationary ring and the rotating ring which are opposite to each other and the other pair of raceways formed on the stationary ring and the rotating ring which are opposite to each other; a pair of revolution speed sensors for sensing revolution speeds of the rolling elements in the two rows respectively; and a calculator for calculating a load applied between the stationary ring and the rotating ring based on sensed signals fed the revolution speed sensors.