US Patent 7717225 Motor-driven steering assist apparatus

A motor-driven steering assist apparatus includes a single unit body covered by first to third housings, an upper end portion of an input shaft and a torque sensor are supported to the first housing, an upper end portion of an output shaft, an electric motor, a worm gear and a worm wheel are supported to the second housing, and a lower end portion of the output shaft is supported to the third housing.