Spring Drive

1977. A young Seiko engineer started to wonder how he could make his dream of "the ever-lasting watch" come true. In his vision: a watch wound by a mainspring and with one-second-a-day accuracy, a precision that only the finest electronic watches could deliver. This engineer, Yoshikazu Akahane, was a persistent and dedicated man. It took him 28 years, countless set-backs and over 600 prototypes, but he and his team eventually succeeded by inventing new technologies in every aspect of the watchmaker's art. In 2005, Seiko Spring Drive came of age.

Four Key features of Spring Drive

High accuracy
The Tri-synchro regulator controls and releases the mechanical, electrical and electro-magnetic energy generated by the mainspring. It replaces the escapement and, with its one-way motion, it is inherently more stable, durable and precise. Spring Drive is accurate to 1 second per day.

Glide-motion
As the movement has no escapement, all the motion within it is circular, in a single direction, allowing the hands to move constantly with a unique glide-motion. Spring Drive is the only watch in the world to express the natural and continuous flow of time.

Long Power Reserve
The new generation mainspring delivers more power, more smoothly and for longer. A special alloy, developed in-house by Seiko, generates increased power in addition to being durable and highly resistant to heat or corrosion. Spring Drive has a power reserve of 72 hours, even if the chronograph is in continuous operation.

Fast winding
In 1959 Seiko invented an original component from the winding mechanism of a mechanical watch, the 'Magic Lever.' It boosted the efficiency of the automatic winding mechanism, by using the energy created by each swing, in both directions, of the rotor. With direct installation to the rotor shaft, the newly designed 'Magic Lever' system delivers more efficient transmission of power than ever.

Mechanism

Source of energy
The sole motive power is the mainspring

Transmission
The power of the mainspring is transmitted via gear train to the hands and to the Tri-synchro regulator.

Regulation
The Tri-synchro regulator controls the speed of the glide wheel and the hands by electromagnetic braking.

Three Key Innovations

The Tri-synchro regulatory
Developed by SEIKO especially for Spring Drive, the Tri-synchro regulator
1.Controls the mainspring's mechanical energy.
2.Converts a small part of this energy into electricity to power the Spring Drive crystal.
3.Generates a magnetic force to regulate the speed of the glide wheel.
These three diverse forms of energy gives the regulator the 'tri' in its name.

The Mainspring
Seiko developed a new high-elasticity alloy "Spron 510" for the mainspring.
SPRON 510* is Seiko's unique alloy and leads the industry and delivers extended power and accuracy.
*SPRON is a registered trademark of Seiko Instruments Inc.

The Magic Lever

Magic Lever is a unique winding system first developed by Seiko in 1959.
In SPRING DRIVE a new Magic Lever winding system fitted directly to the shaft of the rotor gives greater efficiency and allows a shorter winding period and a longer power reserve.

Spring Drive Chronograph

Seiko Spring Drive provides the perfect platform for a luxury chronograph, because elapsed time is measured precisely and not to the nearest fraction. With one-second-a-day accuracy, with its 12 hours duration, with its vertical clutch and column wheel for precise button operation, this is one of the world's great chronographs. Assembled by hand, with 416 parts, 50 jewels, 140 oil points and 5 different lubricants, the Spring Drive chronograph has a power reserve of 72 hours, even when the chronograph is in use

Glide motion hand

The chronograph second hand moves in glide motion and measures up to twelve hours. It stops precisely when the button is pressed, not at the nearest second or 1/10th of a second. The Spring Drive Chronograph is the only watch that can measure with precision the natural and continuous flow of time.

Vertical clutch & Column wheel

Vertical clutch
The vertical clutch delivers high precision to the chronograph operation, and the chronograph second hand never jumps when it starts. This allows a level of accuracy (one second per day) that far exceeds that of any other luxury chronograph.

Column wheel
The Spring Drive chronograph is equipped with a column wheel for maximum stability in the switching mechanism. This eight-pillar component controls the chronograph function with error-free precision, and creates maximum durability and reliability.

Two-step system

The precision and accuracy in chronograph measurement is secured by the two-step push button system. A slight resistance at the halfway point and the reassuringly solid 'click' ensure the operator captures the precise moment to start or stop the chronograph.