Patent ID: 8651744

Claim:
A roller bearing device having a radial-plane arrangement structure of a rotation sensor, the roller bearing device comprising: a roller bearing having a radial plane and an inner ring and an outer ring; an inner-ring supported member supported by the inner ring; an outer-ring supported member supported by the outer ring; and a driver that relatively rotates the inner-ring supported member and the outer-ring supported member, wherein the rotation sensor is arranged between the inner-ring supported member and the outer-ring supported member and outputs a sensor signal that changes according to relative positions thereof, characterized in that the rotation sensor, the roller bearing and the driver are arranged in order from the radially inner side on the radial plane of the roller bearing and the rotation sensor includes: an annular detected member, one of an inner circumference and an outer circumference of which is decentered with respect to a shaft center of the roller bearing; and detecting means for detecting a reluctance change between the detecting means and the detected member, and the detected member is provided in one of the inner-ring supported member and the outer-ring supported member and the detecting means is provided in the other such that the decentered side of the one of the inner circumference and the outer circumference of the detected member which is decentered is opposed to the detecting means, the roller bearing has two different contact angles, and the driver is arranged such that a gap surface of a stator of the driver and a rotor of the driver is located between a first straight line extending from a vertex of the contact angles in a direction of one of the contact angles and a second straight line extending from the vertex of the contact angles in a direction of the other contact angle and on one side of the inner ring and the outer ring, and the driver is arranged such that a whole of the gap surface of the stator of the driver and the rotor of the driver is located within a range of bearing width of one roller bearing as the roller bearing in the axial direction, or such that the length of the gap surface of the stator of the driver and the rotor of the driver in the axial direction does not exceed the bearing width of the one roller bearing in the axial direction.