Spring Drive
Encyclopedia
The Spring Drive is a novel watch movement
that was developed by Seiko Epson
through collaboration with Seiko Instruments
and Seiko Holdings
.
It uses a mainspring
, barrel, automatic winder and stem winding like in a mechanical watch to store the watch energy. The conventional escapement
is replaced with a device that Seiko calls a Tri-synchro Regulator to regulate the unwinding of the mainspring
. The regulator controls the use of the three forms of energy used in the Spring Drive mechanism; the mechanical power of the mainspring, the electrical energy generated from this mechanical power, and the electromagnetic
energy that governs the rotation of the glide wheel. The energy produced by the glide wheel is used to power a control circuit and quartz crystal oscillator
, which in turn regulates the electro-mechanical braking of the glide wheel.
The glide wheel's speed is sampled 8 times per second (i.e. each time it makes a complete revolution around the regulator) and compared with the reference quartz signal by the circuit. A variable braking force is continuously applied to regulate the glide wheel's frequency. This is the only movement with a time-only feedback (or phase-locked) loop in existence today.
The Tri-synchro Regulator's innovations result in a watch where the hands glide instead of ticking as in a conventional mechanical or quartz watch. This is because the movement never stops as in a traditional escapement, it is slowed to the proper speed by the brake. The movement is specified to 1 second accuracy per day. However, 1-2s per week is commonly reported by owners.
The movement is used on the Spring Drive International collection and in some watches of Grand Seiko, Credor, Galante, Izul, Ananta and Prospex series. Complications include moon phase, power reserve, chronograph, sonnerie, GMT and calendar functions. These watches are fairly expensive, with the least complicated models costing several thousand dollars. The top of the line Credor Sonnerie in Rose Gold is over $150,000 and can be considered a grande complication
.
(currently Seiko Epson) in 1977, and patent
s were applied for in 1982. The movement was announced publicly in 1997, presented at the 1998 Basel Watch Fair
and first appeared commercially in the Credor 'luxury watch' range as a limited edition in 1999. A version which included an automatic winder was shown in Seiko models at the 2005 Basel Watch Fair. The internationally available Seiko models were officially launched at the Musée d'Orsay
in Paris
on September 14, and went on sale the following day.
Swatch
's research company ASULAB has developed a conceptually similar movement called the High Precision Mechanics movement. http://www.asulab.ch/EN/montres_en.htm. Several proof of concept prototypes based on the ETA 2824 caliber
were produced in the late 1990s.
Seiko's efforts with the Spring Drive predates ASULAB's HPM, since Spring Drive watches were already on sale in 1999.
Current calibers, with standard features. Time accuracy: monthly rate within ±15 sec (equivalent to a daily rate of ±1 sec) and power reserve (72h) indicator.
Movement (clockwork)
In horology, a movement is the internal mechanism of a clock or watch, as opposed to the case, which encloses and protects the movement, and the face which displays the time. The term originated with mechanical timepieces, whose movements are made of many moving parts...
that was developed by Seiko Epson
Seiko Epson
, commonly known as Epson, is a Japanese technology company and one of the world's largest manufacturers of computer printers, information and imaging related equipment...
through collaboration with Seiko Instruments
Seiko Instruments
, or SII, is a Japanese company, renowned for developing and commercializing semiconductor, micromechatronics, and precision timepiece technology...
and Seiko Holdings
Seiko
, more commonly known simply as Seiko , is a Japanese watch company.-History and ongoing developments:The company was founded in 1881, when Kintarō Hattori opened a watch and jewelry shop called in the Ginza area of Tokyo, Japan. Eleven years later, in 1892, he began to produce clocks under the...
.
It uses a mainspring
Mainspring
A mainspring is a spiral torsion spring of metal ribbon that is the power source in mechanical watches and some clocks. Winding the timepiece, by turning a knob or key, stores energy in the mainspring by twisting the spiral tighter. The force of the mainspring then turns the clock's wheels as it...
, barrel, automatic winder and stem winding like in a mechanical watch to store the watch energy. The conventional escapement
Escapement
In mechanical watches and clocks, an escapement is a device that transfers energy to the timekeeping element and enables counting the number of oscillations of the timekeeping element...
is replaced with a device that Seiko calls a Tri-synchro Regulator to regulate the unwinding of the mainspring
Mainspring
A mainspring is a spiral torsion spring of metal ribbon that is the power source in mechanical watches and some clocks. Winding the timepiece, by turning a knob or key, stores energy in the mainspring by twisting the spiral tighter. The force of the mainspring then turns the clock's wheels as it...
. The regulator controls the use of the three forms of energy used in the Spring Drive mechanism; the mechanical power of the mainspring, the electrical energy generated from this mechanical power, and the electromagnetic
Electromagnetism
Electromagnetism is one of the four fundamental interactions in nature. The other three are the strong interaction, the weak interaction and gravitation...
energy that governs the rotation of the glide wheel. The energy produced by the glide wheel is used to power a control circuit and quartz crystal oscillator
Crystal oscillator
A crystal oscillator is an electronic oscillator circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precise frequency...
, which in turn regulates the electro-mechanical braking of the glide wheel.
The glide wheel's speed is sampled 8 times per second (i.e. each time it makes a complete revolution around the regulator) and compared with the reference quartz signal by the circuit. A variable braking force is continuously applied to regulate the glide wheel's frequency. This is the only movement with a time-only feedback (or phase-locked) loop in existence today.
The Tri-synchro Regulator's innovations result in a watch where the hands glide instead of ticking as in a conventional mechanical or quartz watch. This is because the movement never stops as in a traditional escapement, it is slowed to the proper speed by the brake. The movement is specified to 1 second accuracy per day. However, 1-2s per week is commonly reported by owners.
The movement is used on the Spring Drive International collection and in some watches of Grand Seiko, Credor, Galante, Izul, Ananta and Prospex series. Complications include moon phase, power reserve, chronograph, sonnerie, GMT and calendar functions. These watches are fairly expensive, with the least complicated models costing several thousand dollars. The top of the line Credor Sonnerie in Rose Gold is over $150,000 and can be considered a grande complication
Complication (horology)
In horology , complication refers to any feature in a timepiece beyond the simple display of hours, minutes, and seconds.A timepiece indicating only hours, minutes, and seconds is otherwise known as a simple movement...
.
History
The design was first conceived by Yoshikazu Akahane at Suwa SeikoshaSeikosha
was a branch of the Japanese company Seiko that produces clocks, watches, shutters, computer printers and other devices. It was the root of the manufacturing companies of the Seiko Group.*1881 — Kintarō Hattori opens the watch and jewelry shop "K...
(currently Seiko Epson) in 1977, and patent
Patent
A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....
s were applied for in 1982. The movement was announced publicly in 1997, presented at the 1998 Basel Watch Fair
BaselWorld
Baselworld Watch and Jewellery Show is a trade show for the watch and jewellery industry organized annually in the city of Basel, Switzerland. The international show unites about 2,100 exhibitors from over 45 countries, including the leading watch and jewelry brands, as well as companies...
and first appeared commercially in the Credor 'luxury watch' range as a limited edition in 1999. A version which included an automatic winder was shown in Seiko models at the 2005 Basel Watch Fair. The internationally available Seiko models were officially launched at the Musée d'Orsay
Musée d'Orsay
The Musée d'Orsay is a museum in Paris, France, on the left bank of the Seine. It is housed in the former Gare d'Orsay, an impressive Beaux-Arts railway station built between 1898 and 1900. The museum holds mainly French art dating from 1848 to 1915, including paintings, sculptures, furniture,...
in Paris
Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...
on September 14, and went on sale the following day.
Swatch
Swatch
Swatch is a brand name for a line of wrist watches from the Swatch Group, a Swiss conglomerate with vertical control of the production of Swiss watches and related products...
's research company ASULAB has developed a conceptually similar movement called the High Precision Mechanics movement. http://www.asulab.ch/EN/montres_en.htm. Several proof of concept prototypes based on the ETA 2824 caliber
Caliber (horology)
Caliber: at the beginning the denomination indicated only the size of a watch movement.Today, caliber designs a precise movement type, indicating the size, the style , followed by the mark of the Ebauches manufacturer Caliber: at the beginning the denomination indicated only the size of a watch...
were produced in the late 1990s.
Seiko's efforts with the Spring Drive predates ASULAB's HPM, since Spring Drive watches were already on sale in 1999.
Calibers
Early models, manual wind and 48h power reserve:- 7R68 : 30 jewels, day.
- 7R78 : 30 jewels, day.
- 7R88 : 30 jewels, day.
- 7R99 : 32 jewels.
Current calibers, with standard features. Time accuracy: monthly rate within ±15 sec (equivalent to a daily rate of ±1 sec) and power reserve (72h) indicator.
- 5R64 : 32 jewels, day, small seconds hand.
- 5R65 : 30 jewels, day.
- 5R66 : 30 jewels, day, GMT.
- 5R67 : 30 jewels, Moon Phase indicator.
- 5R86 : 50 jewels, day, GMT, Chronograph.
- 7R06 : 88 jewels, Sonnerie.
- 9R65 : 30 jewels, day.
- 9R66 : 30 jewels, day, GMT.
- 9R86 : 50 jewels, day, GMT, Chronograph.