NSK Demos Integrated Wheel Hub Motor

NSK Ltd. says it has developed an in-wheel motor that integrates two electric motors and a transmission with two planetary gears.

The supplier demonstrated a prototype of the design, which it describes as an industry first, this week at its headquarters in Tokyo. NSK says the system can be adapted to a variety of electrified vehicle architectures to enhance performance, safety and packaging.

The integrated system is more compact than in-wheel motors with separate transmissions, according to NSK. It says the transmission can achieve high drive torque and a sufficient maximum speed with a small motor. The design enables smooth gear changing, including during acceleration, by controlling the speed and torque of the two motors.

In addition to the motors and transmission, NSK’s design consists of a bearing with built-in speed reducer, a one-way clutch unit, a miniature cage and roller bearing, and an anti-corrosion bearing. The company says it wants to commercialize the various components but didn’t provide a timeline or other details.