Three manufacturers of compact municipal vehicles are getting ready to integrate the electric motors for high efficiency wheels’ hubs manufactured by Schaeffler into their production lines. The result? Street sweepers, vans and snow blowers will operate in fully electric modality.
One of the first companies that this year has released on the market a multipurpose vehicle including the technology of Schaeffler motors for wheel hubs is Jungo.
Fully-electric Schaeffler motors for wheel hubs have a structure where the electric motor (stator and rotor), the gearbox and the mechanical friction brake are arranged around the wheel bearing inside the rim. This compact-design envelope frees space in other parts of the vehicle, for instance for the storage of the battery or of the load. Moreover, it offers more design freedom to vehicle manufacturers, allowing them to develop a wide range of mobility formats, including rolling chassis solutions.
The motor for the wheel hub, including the gearbox, is very compact and is framed inside a 14-inch rim. The inverter, on the contrary, is not integrated and can be positioned everywhere in the vehicle. A single inverter controls one or two motors for wheels’ hubs, depending on the application scenario. The motor power is scalable, according to the application, from 7 kW to 26 kW (maximum work power) and reaches a peak of 60 kW for short periods. The torque generated by the electric motor is directly transmitted by the gearbox to the wheel. This direct transmission reduces the energy loss, making the transmission highly efficient. Another key advantage is that torque and rotation direction are singularly controlled for each wheel, resulting in a four-wheel drive vehicle capable of tackling hills with ease, even in wintry road conditions.
Schaeffler is currently developing motors for wheels’ hubs for 48 V and 400 V applications and is exploring the possibility of even higher voltages.