Giving shape to idea years in the making
—How NSK's expertise creates optimized solutions

Long-life technology for high-load drive ball screws

Daisuke

In a ball screw, each ball in the circuit bears load. However, under high loads, this distribution becomes imbalanced and heavier loads act on certain areas of the circuit, shortening the life of the entire ball screw. We saw an opportunity to extend life by tackling the issue of imbalance.

Jun

Since all things are made within tolerances, there is always some level of error. We typically think of the raceway surface of a ball screw as a perfectly rounded helix, but this ideal is difficult to achieve in practice. Such variance is what causes certain areas in a circuit to receive higher loads.
So, we went back to basics in design. We proposed that careful control of internal specifications would relieve such loads. The long-life technology we developed is thanks to production equipment that can consistently deliver on what we envisioned.

Jun

Actually, this project was made possible by work we started seven years ago to improve efficiency. It wasn’t needed at that time, but we thought it had the potential to take production to the next level. As this project got started, someone I worked with from back then suggested that we could use that technology to create a new product. We realized our efforts from then could be re-purposed to tackle issues in development.
I never could have imagined how our work from seven years ago would take shape and evolve with the contributions of other members on the team. It was a truly fascinating experience to be a part of!

Daisuke

We used “real digital twin”² technology to its fullest. Early in the design phase, we ran simulations to test the configuration we thought would result in longer life.
²NSK’s unique development technology that generates an accurate virtual copy of the device or product being developed. This allows engineers to arrive at solutions that break through preconceived ideas by observing the inside of the proposed product in detail and understanding its true nature through deduction and modeling.

Riga

In our evaluations, we tested a real digital twin under load based on customers’ actual usage conditions. Since we were aiming to develop a ball screw with both high load capacity and long life, we needed development analysis that had never been done before.

Jun

With a real digital twin, we could analyze the inner workings of equipment using the machining technologies we were still considering. Alongside increasing technical knowhow, NSK has been pouring investments into real digital twins with efficiency in mind. It’s thanks to these advancements that our analysis capabilities continue to expand. We were able to make accurate micron-level simulations down to 1/100th the width of a human hair! This also spurred development in measurement technologies.

Jun

The test equipment was only at our Kyushu Plant, and the pandemic made it difficult to visit often. There was a lot of pressure to gain as many insights as possible from just a few tests. So, we carefully analyzed and reviewed before going ahead with testing at the plant.

Riga

It was particularly hard to set up the right equipment conditions. We wanted to test harsh conditions much more severe than those typically seen by customers and had some difficulty figuring out how to produce high loads and temperatures. But it was worth it; we would not be satisfied with only tests in ideal conditions!

Daisuke

It was my first time to work with such a diverse range of departments, so that was exciting! I’ve always worked in design, so I didn’t know much about production equipment or measuring devices. It was great to tap into Jun’s insights and to work with actual machines–I gained a ton of knowledge. It was also exciting to talk with other members and see a range of ideas come in from different directions.

Riga

At NSK, cross-functional teams are formed right at the start of a project. By gathering people from design, development, production, facilities, marketing, and so on to share their perspectives, we can be sure that a product matches the market. It also helps bring us together closer as an organization and helps the company make full use of the resources and talent we have. This proven system was indispensable in our development process as well.

Jun

Although I often work with plants to improve products and have ideas on how to solve problems, it’s tough to take this to next level and produce something new. I had a great experience working together with design and development to bring this technology to life. I think it’s a great system because it allows specialists to share their ideas and pursue their own goals.

Riga

We are targeting manufacturers outside Japan in particular with this product. I'm originally from overseas, so the challenge of taking NSK’s products to the world is a big source of motivation for me.

Jun

Although many of NSK’s products operate out of sight, they are hard at work in all kinds of places, meaning the world is filled with equipment connected to my work. The world would stand still without the essential products we make, and by reducing friction and energy loss, they also help improve the environment. I stay motivated by thinking how our efforts keep the world moving and are shaping a better future.