Operating within intense magnetic fields, medical and high-precision equipment demands components that deliver flawless performance without interference. Traditional metal bearings often fall short in such environments. Addressing this critical challenge, Koyo (JTEKT) has advanced ceramic bearing technology for non-magnetic ultrasonic motors, setting new standards for smooth rotation, reliability, and efficiency in MRI and other sensitive applications.
A new benchmark in smooth, reliable rotation for sensitive medical applications
In the world of precision medical equipment — like Magnetic Resonance Imaging (MRI) devices — even the smallest performance inefficiencies can compromise accuracy. Bearings play a pivotal role in ensuring smooth rotation of moving parts, yet conventional metal bearings face limitations in magnetic environments. Responding to this challenge, Koyo (a JTEKT brand) has refined ceramic bearing technology tailored for non-magnetic ultrasonic motors, delivering reliability and performance where it matters most.
The Challenge: Smooth Rotation in a Magnetic Environment
MRI machines generate extremely powerful magnetic fields during operation. Standard metal bearings, containing magnetic materials, can interact adversely with these fields — resulting in uneven rotation, torque fluctuations, and ultimately, compromised precision. For motor manufacturers supplying MRI peripheral devices, maintaining ultra-smooth operation under magnetic influence is critical. Compounding the challenge, existing ceramic bearings on the market often contain microscopic contaminants that affect rotational consistency, and customers frequently need to clean and grease them manually — a time-consuming and quality-variable process.
Problems
- The ceramic bearings on the market can contain microscopic contaminants, and so they do not have sufficient rotational smoothness for use in medical devices.
- Even if all the bearings are sorted and categorized, it takes time and effort to discard the ones that aren’t smooth enough, and it is time-consuming to perform greasing on the remaining ones.
- When customers perform the greasing themselves, they often use products that are not intended for use on bearings, and so issues arise with bearing quality and functionality.
Solutions
- Using clean specifications for cleaning and packaging, in order to ensure smooth rotation
- Delivering pre-greased bearings suited to the usage conditions
Non-magnetic bearings and relative permeability
Non-magnetic Hybrid Ceramic Bearings – 1.01 or lower
Ceramic Bearings – 1.001 or lower
(Ref.) Beryllium copper – 1.001 or lower
Engineering a Solution: Clean, Pre-Greased Ceramic Bearings
To address these issues, Koyo/JTEKT developed a specialized ceramic bearing solution focused on two key innovations:
- Clean Specifications for Cleaning and Packaging: Bearings undergo rigorous cleaning to eliminate microscopic contaminants that can undermine rotational smoothness. They are then packaged in a controlled, cleaner environment to preserve this quality until installation. This level of preparation ensures consistent performance right out of the box.
- Pre-Greased Bearings Optimized for Operating Conditions: Rather than leaving lubrication to end users (who may use inappropriate greases), Koyo’s bearings are pre-greased before delivery, with lubrication chosen based on the customer’s specific load, speed, and environmental requirements. This not only saves time but also safeguards against functionality issues tied to incorrect greasing.
Performance Achieved: Enhanced Productivity and Precision
The result is a ceramic bearing that delivers smoother rotation, improved reliability, and reduced need for customer-side preprocessing. By eliminating unnecessary steps like sorting, cleaning, and greasing at the customer’s end, manufacturers can speed up assembly workflows and enhance device consistency. This innovation supports the stringent precision demands of MRI equipment and other high-magnetic-field environments — including semiconductor manufacturing — where non-magnetic, low-outgassing components are essential.
Looking Ahead
JTEKT continues to push boundaries in bearing technology, offering solutions designed for extreme environments and specialized applications. As industries demand ever greater precision and reliability — especially in medical and high-tech manufacturing sectors — innovations like non-magnetic ceramic bearings will play a vital role in enabling next-generation performance.
