Spring Drive was created by SEIKO after the quartz Astron in 1969. It is based on the principles of all mechanical watch technology. It contains a mainspring, but uses an entirely new system for time regulation. It delivers the equivalent of one second per day accuracy and unique features. Its glide-motion represents the continuous and even motion of time.
The Spring Drive is a watch that was developed by Seiko Epson through teamwork with Seiko Instruments. It uses a mainspring, automatic winder, barrel and stem winding to store the watch energy.
The design was first time visualized by Yoshikazu Akahane at Suva Seikosha in 1977. And, patent was applied for 1982. First introduction was held in 1998 at Basel Watch Fair. A version, which included an automatic winder, was displayed in Seiko models at the 2005 Basel Watch Fair. Seiko Spring Drive Watch models were launched internationally in Paris on September 14, and went on sale the next day.
The traditional escapement is replaced with a device that Seiko calls a Tri-synchro Regulator. This device adjusts the unwinding of the mainspring. The regulator controls the use of the three forms of energies consumed in the Spring Drive mechanism, the first mechanical power of the mainspring, the electrical energy, which is generated from mechanical power, and energy from electromagnetic, which governs the rotation of the glide wheel.
The speed of the glide wheel is 8 times per second, and it is compared with the quartz signal by the circuit. A variable braking force is constantly applied to adjust the frequency of the glide wheel.
The innovation of Tri-synchro Regulator results in no tickling of the watch, like old traditional mechanical or quartz watches. This reason behind is that the movement never stops as in a traditional escapement; it is slowed to the appropriate speed by the brake. The movement is particular to 1 second accuracy per day.
This movement is being used in the Spring Drive International Collection and in some watches of Grand Seiko, CREDOR, GALANTE, PROSPEX series and IZUL. Problems include moon phase, power reserve, chronograph, sonnerie, GMT and calendar functions. These watches are very much expensive, with the least complicated models costing several thousand dollars. The most expensive one is Credor Sonnerie in Rose Gold, which is over $150,000.
The Spring Drive watch offers almost double power reserve, which is of 72 hours, as compared to the mechanical watches which offer that of 40 hours. The winding system in these spring drive watches is very faster; around 30 percent as compared to the mechanical winding. A mechanical watch or time pieces shows the accuracy of only +/- 5 minutes per month. Whereas the Spring Drive Watches show an accuracy of +/- 15 seconds per month. The needle for seconds moves continuously around the dial of the watch, whereas that of a mechanical or quartz moves once in a second. Spring Drive has its motion in one direction and has no escapement. Therefore, needles of Spring Drive Watches move in a very unique and silent way.