The United States Patent and Trademark Office (USPTO) awarded NHBB a patent for a high-speed angular contact bearing containing a unique retainer design that reduces retainer wear and increases bearing life by up to 50% in high-speed and ultra-high-speed applications.
Retainer wear is the leading cause of high speed bearing failure, and preexisting retainer designs had yet to fully resolve a conundrum with high-speed applications, namely retainer wear resulting from the necessity of retainer piloting. NHBB’s patent answers affirmatively the question of whether it’s possible to reduce retainer wear even further in land-piloted designs, which is a critical element of high speed bearing performance.
In high-speed applications, such as a dental handpiece rotating at 500,000 rpm, retainer piloting on the outer land is beneficial to the overall performance of the bearing because it causes the retainer to rotate smoothly, with virtually no wobbling. This smooth operation minimizes vibration and undesirable noise and prevents accelerated deterioration of the retainer caused by uneven wear. But the piloting action causes a predictable amount of wear due to the rubbing action between the land and retainer.
Selecting the right retainer material is a critical factor in minimizing wear induced by piloting. The optimal choice of materials for high-speed applications includes numerous lightweight polymers, like polyimide (PI), polyamide-imide (PAI), and polyetheretherketone (PEEK). These materials are inherently lubricious and durable, but they experience varying degrees of wear when piloted against hardened steel rings.
NHBB’s patented design capitalizes on the performance advantages of land-piloted retainers made of advanced polymers. The unique design adjusts retainer geometry in a way that reduces the contact area between the polymer retainer and the piloting land, which significantly lessens sliding friction and wear. It opens up space to accommodate additional lubrication and minimizes the interference of wear debris and external contaminants with the retainer. Plus, the retainer's shape allows for smooth airflow through the bearing, which is beneficial for air-driven turbine applications.
This innovation will lead to dramatic improvements in bearing performance and life for a diverse range of applications like dental handpieces, electric motors, pumps, and compressors. Testing has demonstrated that NHBB’s innovative angular contact bearing design could potentially increase bearing life by up to 50% in these and many other ultra-high-speed applications.
The development of this patented technology was a coordinated effort between NHBB's Product Development Lab, located in Chatsworth, California, and the Precision Division product engineering team. This lab, which is an extension of NHBB's New Product Development Center (NPDC), specializes in the development and testing of precision miniature and instrument ball bearing designs for customers in the dental, medical, and high technology industries.For more information, contact the Precision Division’s applications engineering department.