NTN Corporation is expanding the mass-production and delivery of a high speed deep groove ball bearing developed for motors fitted to electric vehicles (EV) and hybrid electric vehicles (HEV).
As motors for EVs and HEVs are becoming more compact and lighter, NTN says it has overcome the issues of the conventional product and achieved a higher rotational performance.
Motors for EVs and HEVs have been reduced in size and weight to save electricity and fuel efficiency. In order to achieve more compact size and lighter weight while maintaining the motor’s output torque, bearings for motors needed excellent high speed rotation performance. However, to realize high speed rotation, there have been problems such as distortion and damages of retainer caused by centrifugal force.
The product NTN has developed in 2015 is designed to enhance the strength of retainer by reviewing the materials of retainer. In addition, the pockets where the retainer contacts with rolling elements are designed to minimize distortion caused by centrifugal force, thereby it achieves high speed rotation performance – NTN claims. The dimensions are the same as conventional product, so it can replace the conventional product.
The product is developed mainly for grease lubrication, but it can also be applied under oil lubrication. Depending on the usage conditions, it can be used for high speed rotation with dmn value 1.5 million. In recent years, there has been an increasing trend for motors with oil lubrication, which has excellent cooling effects in order to suppress motor heat generation. Under these situations, NTN has received a large number of requests for oil lubrication and been expanding mass-production and delivery.
With the spread of EVs and HEVs, demand for this product adapting to high speed rotation is expected to increase into the future. NTN says it will continue to contribute to electrification and energy and fuel efficiency savings of automobiles through providing this product into the market.