9R Spring Drive
Spring Drive is a unique watch technology. It generates energy like every other luxury mechanical watch but combines this with an electronic regulator to deliver a level of precision that no mechanical watch can match.
The development of Spring Drive was possible because Grand Seiko is one of the very few manufacturers with mastery of both electronic and mechanical watchmaking.
History
In 1977, Yoshukazu Akahane, a young watch engineer, decided to attempt the seemingly impossible, the creation of an ‘everlasting’ watch. His aim was a traditional watch, powered by a mainspring, that would deliver the one-second-a-day precision of which the company’s electronic watches were already capable. 28 years and 600 prototypes later, he realized his dream and Spring Drive was presented to the world. In 2007, and in the spirit of Akahane’s relentless pursuit of perfection, the Grand Seiko Spring Drive chronograph was born.
9R Spring Drive Movement
Movement Comparison
| Movement | Accuracy | Power reserve | Number of jewels | Features |
|---|---|---|---|---|
| Spring Drive 5 Days Caliber 9RA2 (Automatic with manual winding) |
±10 seconds per month (±0.5 second per day) | Approximately 120 hours (5 days) | 38 jewels | -Offset Magic Lever
-Dual-size Barrels -One-piece Center Bridge -Power reserve indicator |
| Spring Drive 5 Days Caliber 9RA5 (Automatic with manual winding) |
±10 seconds per month (±0.5 second per day) | Approximately 120 hours (5 days) | 38 jewels | -Offset Magic Lever
-Dual-size Barrels -One-piece Center Bridge -Power reserve indicator |
| Manual 8-Day Spring Drive Caliber 9R01 (Manual winding) |
±0.5 seconds per day (±10 seconds per month) | Approximately 192 hours | 56 jewels | -Power reserve indicator
-Quick correction function of time difference |
| Manual-winding Spring Drive Caliber 9R02 (Manual winding) |
±1 second per day (±15 seconds per month) | Approximately 84 hours | 39 jewels | -Torque Return System
-Dual-Spring Barrel -Power reserve indicator |
| AUTOMATIC SPRING DRIVE 3-DAY CHRONOGRAPH GMT Caliber 9R96 (Automatic with manual winding) |
±0.5 second per day (±10 seconds per month) | Approximately 72 hours | 50 jewels | -Power reserve indicator
-Dual time function with 24-hour hand -Quick correction function of time difference adjusting to a calendar -Stopwatch function |
| Automatic Spring Drive 3-Day Chronograph GMT Caliber 9R86 (Automatic with manual winding) |
±1 second per day (±15 seconds per month) | Approximately 72 hours | 50 jewels | -Power reserve indicator
-Dual time function with 24-hour hand -Quick correction function of time difference adjusting to a calendar -Stopwatch function |
| Automatic Spring Drive 3-Day GMT Caliber 9R66 (Automatic with manual winding) |
±1 second per day (±15 seconds per month) | Approximately 72 hours | 30 jewels | -Power reserve indicator
-Dual time function with 24-hour hand -Quick correction function of time difference adjusting to a calendar |
| Automatic Spring Drive 3-Day Caliber 9R65 (Automatic with manual winding) |
±1 second per day (±15 seconds per month) | Approximately 72 hours | 30 jewels | -Power reserve indicator
-Date display |
| Manual-winding Spring Drive Caliber 9R16 (Automatic with manual winding) |
±0.5 second per day (±10 seconds per month) | Approximately 72 hours | 30 jewels | -Power reserve indicator
-Dual time function with 24-hour hand -Quick correction function of time difference adjusting to a calendar |
| Manual-winding Spring Drive Caliber 9R31 (Manual winding) |
±15 seconds per month(±1 second per day) | Approximately 72 hours | 30 jewels | -Dual-Spring Barrel
-Power reserve indicator |
