For Freudenberg Sealing Technologies, the advantages of in-wheel motors (IWM) extend beyond the passenger car segment. The company offers a patented sealing geometry to support original equipment manufacturers (OEMs) and manufacturers of engines ranging from small electric cars to commercial vehicles right at the development stage.
In-wheel motors for electric vehicles offer numerous benefits: components such as transmissions, brakes, and suspensions can either move much closer to the point of power transmission or be completely eliminated.
The decisive advantages of battery-electric vehicles include wheel-specific torque control, enhanced comfort and more design space within the vehicle. This results in a better driving experience, greater range and more flexibility for developers.
In-wheel motors are also of interest for buses due to their lower center of gravity, tighter turning radius and higher load capacity. They can also offer added value as a combined trailer drive for e-trucks.
“The technical challenges for the seal are mainly to ensure reliable protection against dirt and water while minimizing friction losses,” explains Product Developer Luca Breusa.
At low speeds, the seal provides optimal protection against dirt and water and as speeds increase, this sealing effect decreases exponentially. This prevents major friction losses. A key feature of the Freudenberg seal is its dynamic adjustment of sealing effectiveness and friction, which adapts according to the rotational speed of the wheel.
The company has developed two significant seal designs: The cassette seal offers a double sealing lip and mating contact surface installed in a closed system, featuring precisely matched materials made of stainless steel and special rubber compounds. The required speed ranges and contamination protection can be scaled. The cassette seal stands out for its long service life and high functional reliability. It’s capable of achieving up to 500,000 km and protection class IP67. This makes it a maintenance-free, self-lubricating solution throughout its entire service life.
The second design, a V-seal, works in an open system. Its particularly wear-resistant elastomers with excellent sliding properties, combined with attractive manufacturing costs, create a plug-and-play solution designed for flexible applications.
With these two solutions, Freudenberg expertly bridges the gap between the requirements for high sealing performance and low friction losses. The seal geometry can be scaled to an installation space diameter of up to 530 mm and is adjustable to the respective speed range. This allows the seals to be used in applications ranging from small cars to commercial vehicles.
Filed Under: Technology News