Seiko Grand Spring Drive Operating Instruction

BSJ9RCD-A2002

Printed in Japan

Thank you very much for choosing a Grand Seiko watch.
For proper and safe use of your Grand Seiko watch, please
read the instructions carefully in this booklet before using it.

Keep this manual handy for easy reference.

Bracelet sizing is available at the retailer from whom the watch was purchased. If you cannot
have your watch band sized by the retailer from whom the watch was purchased because you
received the watch as a gift, or you moved to a distant place, please contact Grand Seiko
international service network mentioned on CERTIFICATE OF GUARANTEE or our website.
The service may also be available on a chargeable basis at other retailers, however, some
retailers may not undertake the service.

If your watch has a protective film for preventing scratches, make sure to peel it off before using
the watch. If the watch is used with the film on it, dirt, sweat, dust, or moisture may be attached
to the film and may cause rust.

CONTENTS

■ INTRODUCTION - Spring drive watch – ................................................................... 2

• History of Spring Drive ....................................................................................... 3

• Spring Drive Mechanism ................................................................................... 4

• Differences between the Spring Drive and mechanical watch ........................... 7

■ HANDLING CAUTIONS ....................................................................................... 8

■ CHECK THE CALIBER NUMBER AND WATER-RESISTANT LEVEL ............... 9

■ CAUTIONS ON WATER RESISTANCE ............................................................ 10

■ NAMES OF THE PARTS .................................................................................... 14

■ HOW TO USE ..................................................................................................... 15

• Crown .............................................................................................................. 15

• Power reserve indicator ................................................................................... 16

• HOW TO USE ................................................................................................. 17

■ FUNCTIONS OF DIVER’S MODEL .................................................................... 19

• Unidirectional rotating bezel ............................................................................ 19

• Slide adjuster ................................................................................................... 20

■ TO PRESERVE THE QUALITY OF YOUR WATCH .......................................... 21

• After-sale service ............................................................................................. 21

• Guarantee ....................................................................................................... 22

• Daily care ........................................................................................................ 23

• Band ................................................................................................................ 24

• Magnetic resistance (Magnetic influence) ....................................................... 25

• Lumibrite ......................................................................................................... 26

• Troubleshooting .............................................................................................. 27

■ SPECIFICATIONS (Movement) ........................................................................ 28

English

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■ INTRODUCTION - Spring drive watch –

Thank you for purchasing the Grand Seiko Spring Drive watch.

The Spring Drive is Seiko’s unique mechanism in which accuracy is controlled by a

microelectronics quartz mechanism while using the power of the mainspring to move the hands.

The Spring Drive can be called a watch that strongly combines and connects the user with the

latest advancements in technology.

A mechanical watch of taste and refinement with an accuracy equivalent to a quartz watch, this

sophisticated and innovative watch ticks in step with the pace of a person’s life.

This is a watch that creates a lifestyle for modern individuals who seek affluence and

convenience in their life.

That is what the Grand Seiko Spring Drive watch is all about.

History of Spring Drive

Decades-long dream lives in the Grand Seiko

Grand Seiko’s history symbolizes the culmination of efforts and development aiming for better
practical watches.

The Grand Seiko watch was born in 1960, reached the very top in the mechanical watch field
around the world at the end of the 1960’s. After a hiatus of dozen years or so, in 1993, the Grand
Seiko 9F series equipped with world-class quartz movement was released.

In 1998, the 9S series mechanical movement that combined traditional craftsmanship and
advanced technology was developed to reintroduce the Grand Seiko mechanical caliber.
Furthermore, while using the unwinding power of the mainspring as its sole power source, this
Spring Drive realizes much greater accuracy than conventional mechanical watches. The watch
also embodies the concepts of Grand Seiko that continues the challenge of creating the best
practical watch.

1960 ● Released the first Grand Seiko.
1964

1968
1968

1978
1982

1988
1993

1997

1998

1999

2002

2004

2007
2016

2020

● Participated in the Neuchatel Observatory Competition in

Switzerland for the first time.

● Released Japan’s first automatic winding 10-beat model, 61GS.

● Won the first prize in the mechanical wrist chronometer category of
the Geneva Observatory Competition in Switzerland.

● Filed a patent for the Spring Drive mechanism for the first time.

● Filed a patent for the Spring Drive mechanism (registered). Started

initial development.

● Released the first Grand Seiko quartz caliber.

● Started the second development of the Spring Drive.

● Released the Grand Seiko 9F series equipped with world-class

quartz movement.

● Started the third development of the Spring Drive.

● Released technological announcement of the Spring Drive at the
Swiss Society of Chronometry (SSC).

● Exhibited the Spring Drive at BASELWORLD.

● Released the Grand Seiko 9S series mechanical caliber combining

traditional craftsmanship and advanced technology.

● Started the development of the automatic winding Spring Drive.

● Released the manual-winding Spring Drive (CAL.7R68) limited
edition from SEIKO.

● Released the manual-winding Spring Drive (CAL.7R88) from
CREDOR.

● Released the Grand Seiko automatic winding Spring Drive
(CAL.9R65).

● Released the first Grand Seiko chronograph (9R86).

● Released 9R01 8Days which realized a long continuous operating

time with three barrels.

● Released Spring Drive 9RA5 which was evolved to have high
accuracy and 5-day power reserve.

English

INTRODUCTION

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- Spring drive watch –

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Spring Drive Mechanism 1

Taste of a Mechanical Watch
+
High accuracy equivalent to a Quartz Watch
That is the concept of the Spring Drive.

Let’s start from the drive method of a watch.

The method for driving a watch is divided into two types.

They are mechanical type and quartz type.

In a mechanical watch, the mainspring is wound and its unwinding power moves the hands.

Amazing mechanism created by high quality craftsmanship,

and admiration goes to skilled craftspersons with passion.

You can feel the appreciation and personal touch of the craftspersons in the ticking sound.

On the other hand, with quartz watches, the quartz is oscillated by a battery and the hands are

turned by a motor.

It is characterized by accuracy using state-of-the-art technology.

What is the Spring Drive like?

This is not a mechanical watch or a quartz watch.

In one word, this is a “mechanical watch having accuracy equivalent to a quartz watch.”

The Spring Drive is a self-contained drive system that realizes accuracy equivalent to a quartz

watch with only the power of the mainspring and has no battery, motor, or secondary battery.

Accuracy of monthly rate of ±10 seconds or ±15 seconds equivalent to a quartz watch is

achieved while using a mainspring.

The Spring Drive is Seiko’s proprietary mechanism which is made available only by SEIKO’s

unique combination of skills in both mechanical and electronic micro-engineering.

Then, how could it be possible to achieve such a degree of accuracy?

That is explained on the next page.

Spring Drive Mechanism 2

The power of the mainspring is regulated by electronic
control. That is the essence of the Spring Drive.

What controls the accuracy of a mechanical watch is

the balance spring, a part of the speed-regulating unit, called the balance.

This part influences the accuracy to some extent

because it is made of metal which expands and contracts with changes in temperature.

The Spring Drive is

completely different from a mechanical watch in this speed-regulating unit.

The Spring Drive is powered by a mainspring, but adopts an electronic speed-regulating unit

comprising a generator, IC, and crystal oscillator.

In a little more detail,

at the end of the train wheel that moves the hands, a series of speed increasing wheels with a

glide wheel are provided.

The unwinding power of the mainspring rotates the glide wheel, generating electricity in the coil

to drive the crystal oscillator and IC.

The IC controls the spinning speed of the glide wheel by applying and releasing the

electromagnetic brake, while comparing the accuracy of the electric signals generated by the

crystal oscillator and the spinning speed of the glide wheel.

In addition, by making the energy transfer of the train wheel efficient and adopting an IC that

drives with low power consumption, power reserve far exceeding normal mechanical watches

is realized.

An unprecedented drive system which offers quartz accuracy.

This is the Spring Drive.

English

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Spring Drive Mechanism 3

Here is the step-by-step description of the Spring Drive in
an easy-to-understand manner.
This is how the Spring Drive works.

Mainspring

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2

The mainspring is wound by rotation of the oscillating
weight (or by turning of the crown), and its unwinding
power is the sole power source.

Gear train • hands

The unwinding power of the mainspring is transmitted via
the gear train to move the hands. No motor or battery is
mounted.

Differences between the Spring Drive and
mechanical watch

For the Spring Drive, the mainspring is wound and
the unwinding power of the mainspring moves the
hands in the same manner as the mechanical watch.
It differs from the mechanical watch only in the
speed-regulating unit (mechanism for controlling
accuracy).

◎ Temperature change

Accuracy of mechanical watches depends on a balance spring attached to a part called the
balance. This part has properties for expanding and contracting with temperature changes, and
influences the accuracy of a watch. Accuracy of the Spring Drive is never largely influenced by
temperature changes like that of mechanical watches since the crystal oscillator controls it.
(Note) Accuracy of the Spring Drive

Average monthly rate of ±10 seconds or ±15 seconds is the accuracy of a watch when
it is worn on a wrist at a temperature range between 5°C and 35°C.

English

◎ Difference in position

For mechanical watches, the accuracy is influenced even by a difference in position or direction
of a watch. This is also caused by the balance that controls the accuracy of mechanical watches.
Due to the difference in position, the area where the shaft of the balance contacts with other
parts differs, and such differences in resistance influence the accuracy. As the Spring Drive
adopts a crystal oscillator not a balance, the accuracy is not influenced by a difference in
position.

◎ Impact

Mechanical watches are susceptible to impacts. If a mechanical watch was subject to impact,
amplitude of vibration of the balance (angle for which the balance rotates right and left) is
changed, and even the form of the balance spring is changed. In this regard, the Spring Drive
is superior to mechanical watches in impact resistance because it adopts a crystal oscillator
not a balance.

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Tri-synchro regulator

The unwinding power of the mainspring also rotates the
glide wheel. This generates small electricity in the coil to
drive the IC and crystal oscillator. At the same time, an
electric magnetic field is generated on the glide wheel.
The IC detects the spinning speed of the glide wheel
based on the accuracy of the electric signals of the crystal
oscillator, and adjusts the spinning speed of the glide
wheel while applying and releasing the electromagnetic
brake.

◎ Overhaul

Parts that become worn or severely damaged are the balance, pallet fork, and escape wheel
& pinion which are collectively called the speed-regulating unit or escapement. These parts
“come into contact or collide” mutually and control unwinding of the mainspring.
For the Spring Drive, wear and damage occur less than mechanical watches since the spinning
speed of the glide wheel is adjusted by a “contact-free” electromagnetic brake. However, as
the structure of gear train is the same as mechanical watches, abrasion powder may be
generated by contact of the wheels & pinions. An overhaul is recommend every three to four
years.

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