Patent ID: 8307931

Claim:
A sensor equipped axle unit having an in-wheel type motor built therein, comprising: a train of component parts comprising a hub bearing assembly comprising an outboard segment supporting a vehicle driven wheel of an automotive vehicle fitted thereto, an electric motor, a reduction gear unit to reduce rotation of the electric motor and transmit it to the hub bearing assembly, and a brake assembly, the train of component parts all being arranged coaxially on a center axis of a vehicle drive wheel; and sensors to measure forces acting at a point of contact of the vehicle drive wheel and a road surface in three axis directions perpendicular to each other, respectively, from the status of at least one component part of the train of component parts, wherein the sensors comprise a braking force sensor to detect the braking force applied to brake pads of the brake assembly, an axial strain sensor to measure the axial strain acting on a stationary raceway ring of the hub bearing assembly, the axial strain sensor being fitted to the stationary raceway ring, and a radial strain sensor to measure the radial strain acting on a stationary raceway ring of the hub bearing assembly, the radial strain sensor being fitted to a casing of the reduction gear unit.