Patent ID: 6882142

Claim:
A sensor-equipped bearing assembly which comprises: inner and outer races serving respective race members, the inner race being positioned inside the outer race with an annular bearing space defined therebetween; at least one row of rolling elements rollingly accommodated within the annular bearing space while being interposed between the inner and outer races; and a rotation sensor detecting a rotational speed of a rotating element, said rotation sensor comprising a to-be-detected portion mounted on one of the inner and outer race members, which is rotatable, and having such a magnetic characteristic that N and S poles are alternately magnetized in a direction circumferentially of the race members. a magnetic detecting portion mounted on the remaining one of the inner and outer race members, which is stationary, in face-to-face relation with the to-be-detected portion, said magnetic detecting portion including a plurality of magnetic sensors outputting an analog signal and arranged in a direction circumferentially of the race members, and a differential output generator processing a differential output of two magnetic sensors as an encoder signal for one phase, wherein each of the magnetic sensors providing the differential output comprises a Hall element; and an output reference voltage aligner controlling an electric power source voltage for one of the Hall elements with respect to a reference voltage defined at an output intermediate point of the other of the Hall elements such that an output intermediate point of such one of the Hall elements attains the substantially same voltage as the reference voltage.