Q: What is Spring Drive?
"Spring Drive" is a movement found in Grand Seiko and Credor watches. What kind of movement is it?
A: What is Seiko's Spring Drive?
Seiko's Spring Drive, released in 1999, can be summed up simply as follows:The heart of a mechanical watch is replaced with a quartz crystal oscillator instead of the balance wheel that oscillates back and forth.Specifically, the power generated by the unwinding of the mainspring turns the rotor, generating electricity, which then vibrates the quartz movement, keeping the watch running at a constant rate.
Spring Drive video
The benefits of Spring Drive
The advantage is that it has the strong power of a mechanical movement and the high accuracy of a quartz movement. Generally, quartz watches run for much longer than mechanical watches, but the trade-off is that the power to move the hands is only about half that of a mechanical movement.
Spring Drive, which uses a mainspring as its power source, has the precision of a quartz movement, but can also move thick, long hands like a mechanical watch. Furthermore, because it does not have a balance wheel, the watch will barely go out of sync even if subjected to a strong shock, and it is also resistant to magnetism.
Disadvantages of Spring Drive
On the other hand, the disadvantage is that the mechanism is quite complicated, so it is not suitable for mass production, and as a result, the price is inevitably high.
Next-generation Spring Drive movement
This model is equipped with the Cal. 9RA2, which moves the power reserve indicator from the dial side of the Cal. 9RA5 to the case back. The movement can be viewed through the transparent case back. Automatic Spring Drive (Cal. 9RA2). 38 jewels. Power reserve of approximately 120 hours. Stainless steel case (diameter 40mm, thickness 11.8mm). Water resistant to 10 bar. Price: 1,276,000 yen (tax included).
This watch is equipped with the unprecedented, ultra-high-precision Spring Drive movement, Caliber 9RB2, which achieves an annual accuracy of ±20 seconds. "UFA" stands for Ultra Fine Accuracy, and is a reference to the "VFA (Very Fine Adjusted)" designation given to a high-precision model released in 1969. Caliber 9RB2 features a Spring Drive control IC with added temperature compensation and a pre-aged, selected quartz movement. The addition of a regulator switch improves the overall system's accuracy while making it easier to maintain, achieving an extremely high level of perfection. The dial motif features a frost-covered forest. The exterior is made of lightweight, textured bright titanium. Spring Drive automatic movement (Caliber 9RB2). 34 jewels. Power reserve: approximately 72 hours. Bright titanium case (37mm diameter, 11.4mm thick). Water resistant to 10 bar. Price: ¥1,518,000 (tax included). Available at Grand Seiko boutiques and Grand Seiko salons.
This diver's watch features the Cal. 9RA5 automatic Spring Drive movement with a power reserve of approximately 120 hours. It combines the functionality of a diver's watch with the design codes of the Evolution 9 collection, showcasing the dynamic swells created by the collision of the Kuroshio and Oyashio currents off the coast of Japan on the dial. The blue ceramic bezel insert, Grand Seiko's brand color and evocative of the rich ocean, adds to the aesthetic appeal. The use of Spring Drive in a sports watch, where reliability is essential, speaks to its refined quality. Automatic Spring Drive (Cal. 9RA5). 38 jewels. Power reserve of approximately 120 hours. Bright titanium case (43.8mm diameter, 13.8mm thick). Water resistant to 200m. Price: ¥1,683,000 (tax included).
