GS Grand Seiko

Spring Drive. Born of a dream. Realized through innovation.

Before Spring Drive, the choice was stark. Either you wore a mechanical watch and enjoyed its traditional character and tolerated its relative imprecision or you wore a quartz watch that was up to ten times more accurate but required a battery. Finally, in 1998, Spring Drive resolved this dilemma by combining the best of both of the existing two watch technologies. As the name implies, it was driven by a spring but it delivered the precision of an electronic watch. It took a team of engineers and watchmakers over twenty years to turn their dream into a reality and a further six years before an automatic winding version made Spring Drive suitable for incorporating into Grand Seiko. It was a long road but one that ultimately opened a new horizon in watchmaking.

Seiko Epson’s watch engineers, Osamu Takahashi (left) and Kunio Koike (right). Takahashi was engaged in the development of Spring Drive from its early research stage. Koike brought his skills in circuit design to the project. Both were on the team that finally realized Akahane’s dream with the Grand Seiko Caliber 9R in 2004.

It started with a dream. In the late 1970s, Yoshikazu Akahane, an engineer at Suwa Seikosha (currently Seiko Epson), had conceived the principle of a highly accurate movement known as “Twin quartz” and was deeply involved in its development and commercialization. Two tuning fork-shaped quartz oscillators were set into this movement; one was used to measure temperature and the other time. In this way, variations in precision due to temperature change were detected and the time signal corrected to achieve a precision rate of ten seconds a year. It was a brilliant watch movement that took the quartz watch to a new level of precision but was not enough to satisfy Akahane. Even as he immersed himself in the intricacies of cutting edge quartz technology, he dreamed of creating something completely different that would revolutionize horology. His goal was what he called an “everlasting” watch. He decided to try to achieve the seemingly impossible, the creation of a traditional watch, powered by a mainspring, that would deliver the one-second-a-day precision of which the electronic watch was already capable. Akahane was not alone in his aspiration. Other watchmakers of the day also attempted to make a watch with this kind of mechanism but only Akahane and the engineers who joined him on his journey had the skill, determination and resources to realize the dream.

One of Akahane’s team was Osamu Takahashi. As soon as he joined the company, Takahashi was made aware of the project because, as early as 1978, Akahane had filed a patent for the “development of an electronically regulated mechanical watch that is powered by a spring.” Later, the patent rights were granted but, even before this, serious research had been conducted and prototypes made. Takahashi, however, never even dreamed that he would be entrusted with this development project but was delighted to join the team in 1993. He had studied fluid dynamics in graduate school and used the skills he had learned there to develop a unique mechanism for what became Spring Drive. He created the smooth, sweeping movement of the seconds hand using the viscosity of silicon oil and a hairspring. While a brilliant and important step forward for the project, this left the central challenge unresolved. The whole mechanism required too much power and the problem seemed intractable. Officially, the project was shelved but, quietly and stubbornly, Akahane, Takahashi and the other members of the team continued their research. Akahane was not a man who gave up easily and he was determined that his dream would never die. To start with, progress was painfully slow but, thanks to advances made in other areas, including the creation of the Kinetic caliber back in 1988, the impossible started to become foreseeable.

The prototype completed in 1997. The round metal case is the mainspring barrel. The coils are part of the generator. Crucially, this prototype proved the concept was viable as is clear from the absence of both a battery and a step motor.

Kunio Koike shared Akahane’s determination to realize the Spring Drive dream. He had become a part of the development team in early 1997 and was charged with circuit design, an area that would prove pivotal. Although the company had already amassed a wealth of expertise in areas such as low-power technology and ultra-small power generators, these advances alone barely made a dent in the problem. It became the team’s obsession. Takahashi, who now led them, would drop by Koike’s desk almost every night to debate possible solutions. Takahashi even went back to his books. He started to study the fundamentals of electricity and related technologies. In this process, he thought anew about the possibility of using a voltage amplifier circuit, as this might allow a quartz crystal and an IC to operate on just a small amount of electricity. Maybe he and Koike had found part, but only part, of the solution. They knew that they would also have to make major advances in every other aspect of watchmaking as well to realize the dream of the “everlasting watch”.

In order to activate a quartz crystal using the power generated through a mechanical movement, the power generation efficiency had to be enhanced by a massive amount while at the same time the power consumption of the integrated circuit needed to be greatly reduced. From the late 1990s, the pace of the research and development progressed more rapidly and, in 1997, the company put its full resources into the project. By now, Akahane had risen to the position of Chief Operating Officer of the Watch Operations Divison and it was he who gave the project the official go-ahead. What had started as an entirely personal challenge was now a company-wide priority. We can only imagine his satisfaction and excitement.