Switches get smaller and smarter

Kiyoko Toyama began her career at NKK Switches in 1981, after graduating from Alverno College (Wisconsin) with a bachelor's degree in management. A native of Kyoto, Japan, Toyama's bilingual, bi-cultural background has proved advantageous in her career at NKK. As the only female president in the multi-billion-dollar American switch industry, Toyama determines the direction of NKK in relation to its products, resources, and the market. She also develops and executes business plans and encourages, motivates, and guides employees to achieve both personal and company goals.

Although the switch market is relatively mature, it continues to evolve with the introduction of new technologies that have unique advantages that can benefit design engineers. Choosing among all the different alternatives is now the major challenge.

DESIGN NEWS: NKK Switches of America just celebrated its 20th anniversary. What changes have you seen in the switch industry and the technology over the past two decades?

Toyoma: There have been lots of changes over the years, but probably the biggest trend that we are seeing is the advent of many different kinds of switch technologies, including tactile and membrane switches. The interesting thing, though, is that while we keep adding new products, we have not dropped very many at all. NKK now has 76 switch families with more than 3 million different part numbers.

In fact, in the 1980s, people were talking about pushbutton switches going away, and while the market has decreased somewhat, they still get designed into many applications. Engineers now have many more choices when it comes to switch technology, which makes their job more challenging.

Q: What do mechanical engineers need to know about the requirements of their applications in order to achieve success in designing with switches?

A: Unfortunately, the switch is often one of the last items to be considered in an overall design. While we may not ever be able to change that mindset, we do try to educate engineers that they need to consider how the switch is going to be actuated-does the application, for example, require that once the button is pushed the light stays on, or not? Another critical thing engineers need to make sure of is that they leave sufficient room behind the panel for the switch device. They should also consider what type of power is available, and also how the switch is going to be mounted. Design engineers need to understand that taking the time to do a little upfront homework is going to go a long way to ensure the success of their switch application.

Q: Miniaturization is a major trend in switch design today. What challenges does the industry face as switches become smaller?

A: The trend toward small switches has posed challenges for switch makers, primarily because design engineers still demand the crisp actuation and reliability that they are accustomed to with larger-size switch products. To meet this requirement, NKK was one of the first companies to introduce a self-wiping contact. In essence, the contact area is wiped clean of any dirt or debris that could impact the reliability of the switch each time the switch is activated. As switch real estate shrinks, we've also had to come up with new inspection techniques to determine whether or not the internal contact is properly assembled. On the positive side, advances in electronics technology and mounting methods-such as the trend away from through-hole to surface mount techniques-have enabled us to shrink the size of our switch devices.

Q: Can you give us a sneak preview of some switch technologies coming down the pipeline?

A: More switches in the future are going to be software-driven. For example, we recently introduced the programmable LCD switch, which features an LCD display on top of the pushbutton. The programmable capability allows a single switch to have multiple functions, thereby reducing the need to have multiple switches in a single application. In some cases, design engineers are combining programming switches with traditional switches-in effect they are using a pushbutton switch to activate a programmable switch. We are seeing design engineers coming up with very clever switch designs today.