About Grand Seiko SBGC005G
Spring Drive is Seiko’s exclusive movement that achieves an unprecedented level of accuracy (+/- 15 seconds per month on average, equivalent to +/- 1 second per day) by regulating a spring-driven watch with state-of-the-art electronic technology that functions without batteries or other external power source.
As in conventional mechanical watches, the sole power source of Spring Drive is a mainspring that can be wound by the motion of an oscillating weight or by winding the crown. And just as in mechanical watches, the mainspring drives a series of gears that rotate the hour, minute and second hands. A rotor, connected to the end of these gears, generate a small electrical charge that activates an electronic circuit and quartz oscillator.
The Tri-synchro regulator is a unique speed controller for Spring Drive that replaces the escapement, which is a mechanical speed control device used in almost all conventional mechanical watches. The Tri-synchro regulator moves the second hand in a smooth motion, without ticking and with extreme accuracy.
Some 80% of the components in a Spring Drive caliber are the same as those in a luxury mechanical watch. Spring Drive is a movement powered by a spring, just like a mechanical watch, with a different kind of regulator and combines the long-lasting autonomy of a mechanical watch with the precision that, until now, only electronic watches could provide.
To ensure reliable and accurate operation, all these parts need to be manufactured to the highest standards of precision, and assembling them requires superior craftsmanship.
The development of the Spring Drive movement caliber 9R was made possible because Seiko is one of the very few manufactures with expertise in both mechanical and quartz watches.
Since the first Grand Seiko Spring Drive in 2004, new movements have been created with even more complex mechanisms–including the GMT in 2005 and chronograph with GMT in 2007. Showing that with the Spring Drive caliber 9R, time never loses momentum.
Grand Seiko SBGC005G Features :
- Screw down crown
- Screw back
- See-through back
- Dual time function with 24-hour display
- Stop watch
- Power reserve display function
- Quick correction function of time difference adjusting to a calendar
- Power reserve: Over 72 hours
Grand Seiko SBGC005G History :
Prior to 1960, to challenge the status of Swiss watches and change the perception of Japanese watches, Daini Seikosha and Suwa began the discussion of a product line that can match the quality of Swiss watches under the suggestion of the parent company. At the time, Suwa Seikosha Co. was in charge of manufacturing men’s watches, so it was decided that Suwa would be producing the first Grand Seiko (GS).
The first Grand Seiko was released in 1960, it was based on Seiko’s previous high-end watch, CROWN. This Grand Seiko has a 25-jewel, manual-winding, 3180 caliber, and only 36,000 units were produced. This was also the first chronometer-grade watch manufactured in Japan, and it was based on Seiko’s own chronometer standard.
The design language of the Grand Seiko was set in 1967, with the creation of Grand Seiko 44GS. The 44GS set the ground for all future Grand Seiko with nine elements. These elements help improve the legibility of the watch under different situations, and create a sharp, crisp visual impression:
- Double width index at 12 o’clock
- Multi-faceted rectangular markers
- Highly polished bezel
- Highly polished planes and two-dimensional surface
- Half recessed crown
- Flat dial
- Multi-faceted hour and minute hands
- Curved side line
- Reverse slanted bezel wall and case side
- Dress style with simple but beautiful design
- Zaratsu polishing
source : wikipedia