HUB UNIT WITH SENSOR

A hub unit with a sensor comprises a hub unit 1 including a body-side raceway member 3, a wheel-side raceway member 4 and two rows of rolling elements 5, and a sensor device 2. The sensor device 2 includes a magnetostrictive sensor 8 for detecting the inverse magnetostrictive effect, and the magnetostrictive sensor 8 is mounted to the body-side raceway member 3 so as to be capable of measuring the tensile strain in the uppermost part of an inner wheel 17 of the wheel-side raceway member 4. From the output of the magnetostrictive sensor 8, the tire grounding load and the rotational velocity are detected.