Chapter 1

The 9R Spring Drive seconds hand and the natural flow of time.

Spring Drive is a watchmaking technology that reflects the true nature of time with a uniquely Japanese aesthetic. Crafted within the Shinshu Watch Studio, located in a Seiko Epson facility in Nagano Prefecture, it uses a mainspring as its power source, just like a mechanical watch. It does so while maintaining the precision of an electronic watch with an integrated circuit and a crystal oscillator. Forged through the blending of technologies and crafts, this rare advance in watchmaking could only have come about through a mastery of both mechanical and electronic watchmaking, in which the drive to select the best attributes of each was unleashed.

The story of Spring Drive began in 1977 with Yoshikazu Akahane, a young engineer at Suwa Seikosha (now Seiko Epson Corporation) whose dream was to create an ideal watch combining the accuracy of an electronic timekeeper with power derived from a mainspring. After more than 20 years of development, the dream was realized in 1999 with the first commercially available Spring Drive movement. In 2004, enhancements to the platform allowed the first Grand Seiko Spring Drive, which featured automatic winding and three days of power reserve.

In 2024, Grand Seiko celebrates the 20th anniversary of its landmark 9R movement series, which uncannily reflects the natural, silent, and continuous flow of time in a manner that calls to mind the motions of the very celestial bodies from which humans first derived the notion of time.

Poetic yet technical, handcrafted yet advanced, full of power yet efficient in its use thereof, Spring Drive has captured the imagination of watch enthusiasts through its many seeming contradictions. It has the nostalgic charm, beauty, and soul of a spring-powered mechanical watch, yet it brings the precision and accuracy of modern electronic watches that receive power from a battery.

A Spring Drive watch’s signature is the smooth glide of its seconds hand, which rounds the dial without the telltale tick or shudder of a mechanical watch. This is because, in Spring Drive, all the parts turn smoothly in a continuous motion, just as the earth does on its axis. In this way, Spring Drive transcends function and horological expectations to harmonize with the natural flow of time. This representation of time’s eternal and silent passing has become a recognized symbol of Grand Seiko and an embodiment of the brand’s philosophy, “The Nature of Time.”

The key to the glide of the Spring Drive seconds hand is in the Tri-Synchro Regulator, which plays the part of the regulating mechanism in the 9R movement. Whereas most mechanical watches have a club tooth escapement (Swiss lever escapement), whose locking and unlocking causes a ticking sound, the Tri-Synchro Regulator uses energy originating in the mainspring to generate electricity and to apply a silent electromagnetic brake to the end of the gear train, the glide wheel. Its harnessing of three types of energy, mechanical power, electrical power, and electromagnetic power, is what gives the Tri-Synchro Regulator its name. By avoiding the small collisions of the club tooth escapement, Spring Drive and its signature seconds hand can glide silently and smoothly around the dial while maintaining an accuracy of ±0.5 second per day in some models and ±1 second per day in others.

The pursuit of harmony with nature is a theme touched upon in many watches from Grand Seiko and the Shinshu Watch Studio in particular. One watch that perfectly expresses this spirit is the SBGA211 “Snowflake,” whose snowy white dial can transport its wearer to Shinshu’s Hotaka Mountains, which are covered in snow several months each year. Powered by the mainstay Caliber 9R65 – the original Grand Seiko Spring Drive movement from 20 years ago – its tempered blue seconds hand moves with a quiet precision.

Silence, precision, and harmony with the natural flow of time: These are the qualities that have defined the 9R movement family for the last 20 years. Every Spring Drive watch holds the dreams of the generations of engineers who set in motion a gliding seconds hand expressing Japan’s conception of time as ever-flowing. With this smoothly gliding seconds hand, Spring Drive is yet another way in which Grand Seiko expresses “The Nature of Time.”