History of watches
Encyclopedia
Watch
es evolved from portable spring driven clocks, which first in the 15th century. Portable timepieces were made possible by the invention of the mainspring
. Although some sources erroneously credit Nuremberg
clockmaker Peter Henlein
(or Henle or Hele) with inventing the mainspring around 1511, many references to 'clocks without weights' and two surviving examples show that spring powered clocks appeared in the 15th century. Henlein is also often credited with constructing the first pocketwatches, mostly because of a passage by Johann Cochläus in 1511:
and because he was popularized in a 19th century novel. However, many German clockmakers were creating miniature timepieces during this period, and there is no evidence Henlein was the first. Also, watches weren't widely worn in pockets until the 17th century.
. The face was not covered with glass, but usually had a hinged brass cover, often decoratively pierced with grillwork so the time could be read without opening. The movement was made of iron or steel and held together with tapered pins and wedges, until screws began to be used after 1550. Many of the movements included striking
or alarm
mechanisms. They usually had to be wound twice a day. The shape later evolved into a rounded form; these were called Nuremberg eggs. Still later in the century there was a trend for unusually shaped watches, and clock-watches shaped like books, animals, fruit, stars, flowers, insects, crosses, and even skulls (Death's head watches) were made.
It should not be thought that the reason for wearing these early clock-watches was to tell the time. The accuracy of their verge and foliot movements was so poor, perhaps several hours per day, that they were practically useless. They were made as jewelry and novelties for the nobility
, valued for their fine ornamentation, unusual shape, or intriguing mechanism, and accurate timekeeping was of very minor importance.
s (the woman's watch remained a pendant into the 20th century). This is said to have occurred in 1675 when Charles II of England
introduced waistcoat
s. To fit in pockets, their shape evolved into the typical pocketwatch shape, rounded and flattened with no sharp edges. Glass was used to cover the face beginning around 1610. Watch fobs began to be used, the name originating from the German word fuppe, a small pocket. The watch was wound and also set by opening the back and fitting a key to a square arbor, and turning it.
The timekeeping mechanism in these early pocketwatches was the same one used in clocks, invented in the 13th century; the verge escapement
which drove a foliot
, a dumbbell
shaped bar with weights on the ends, to oscillate back and forth. However, the mainspring
introduced a source of error not present in weight-powered clocks. The force provided by a spring
is not constant, but decreases as the spring unwinds. The rate of all timekeeping mechanisms is affected by changes in their drive force, but the primitive verge and foliot mechanism was especially sensitive to these changes, so early watches slowed down during their running period as the mainspring ran down. This problem, called lack of isochronism
, plagued mechanical watches throughout their history.
Efforts to improve the accuracy of watches prior to 1657 focused on evening out the steep torque
curve of the mainspring. Two devices to do this had appeared in the first clock-watches: the stackfreed and the fusee. The stackfreed, a spring-loaded cam
on the mainspring shaft, added a lot of friction and was abandoned after about a century. The fusee was a much more lasting idea. A curving conical pulley
with a chain wrapped around it attached to the mainspring barrel
, it changed the leverage as the spring unwound, equalizing the drive force. Fusees became standard in all watches, and were used until the early 19th century. The foliot was also gradually replaced with the balance wheel
, which had a higher moment of inertia
for its size, allowing better timekeeping.
to the balance wheel, an invention disputed both at the time and ever since between Robert Hooke
and Christiaan Huygens. Prior to this, the only force limiting the back and forth motion of the balance wheel under the force of the escapement was the wheel's inertia
. This caused the wheel's period to be very sensitive to the force of the mainspring. The balance spring made the balance wheel a harmonic oscillator
, with a natural 'beat' resistant to disturbances. This increased watches' accuracy enormously, from perhaps several hours per day to perhaps 10 minutes per day, resulting in the addition of the minute hand
to the face from around 1680 in Britain and 1700 in France. The increased accuracy of the balance wheel focused attention on errors caused by other parts of the movement
, igniting a two century wave of watchmaking innovation. The first thing to be improved was the escapement
. The verge escapement was replaced in quality watches by the cylinder escapement, invented by Thomas Tompion
in 1695 and further developed by George Graham
in the 1720s. In Britain a few quality watches went to the duplex escapement, invented by Jean Baptiste Dutertre in 1724. The advantage of these escapements was that they only gave the balance wheel a short push in the middle of its swing, leaving it 'detached' from the escapement to swing back and forth undisturbed during most of its cycle.
During the same period, improvements in manufacturing such as the tooth-cutting machine devised by Robert Hooke
allowed some increase in the volume of watch production, although finishing and assembling was still done by hand until well into the 19th century.
view of watches as scientific instruments brought rapid advances to their mechanisms. The development during this period of accurate marine chronometer
s to determine longitude
during sea voyages produced many technological advances that were later used in watches. It was found that a major cause of error in balance wheel timepieces was changes in elasticity
of the balance spring
with temperature changes. This problem was solved by the bimetallic temperature compensated balance wheel
invented in 1765 by Pierre Le Roy
and improved by Thomas Earnshaw
. This type of balance wheel had two semicircular arms made of a bimetallic construction. If the temperature rose, the arms bent inward slightly, causing the balance wheel to rotate faster back and forth, compensating for the slowing due to the weaker balance spring. This system, which could reduce temperature induced error to a few seconds per day, gradually began to be used in watches over the next hundred years.
The going barrel invented in 1760 by Jean-Antoine Lépine
provided a more constant drive force over the watch's running period, and its adoption in the 19th century made the fusee
obsolete. Complicated pocket chronometers and astronomical watches with many hands and functions were made during this period.
, invented by Thomas Mudge in 1759 and improved by Josiah Emery in 1785, gradually came into use from about 1800 onwards, chiefly in Britain; it was also adopted by Abraham-Louis Breguet, but Swiss
watchmakers (who by now were the chief suppliers of watches to most of Europe) mostly adhered to the cylinder until the 1860s. By about 1900, however, the lever was used in almost every watch made. In this escapement the escape wheel pushed on a T shaped 'lever', which was unlocked as the balance wheel swung through its center position and gave the wheel a brief push before releasing it. The advantages of the lever was that it allowed the balance wheel to swing completely free during most of its cycle; due to 'locking' and 'draw' its action was very precise; and it was self-starting, so if the balance wheel was stopped by a jar it would start again. Jewel bearing
s, introduced in 1702 by Nicolas Fatio de Duillier
, also came into use for quality watches during this period.
Watches of this period are characterised by their thinness. New innovations, such as the cylinder and lever escapements, allowed watches to become much thinner that they had previously been. This was also in accordance with a change in fashion. Deep, verge movements were no longer attractive, hence the arrival of the epithet 'Onion'.
allowing some degree of standardisation and interchangeability of parts on watches fitted with the same calibre.
Watch manufacturing really changed from assembly in watchmaking shops to mass production
with interchangeable parts
, as from 1854, pioneered by the Waltham Watch Company
, in Waltham, Massachusetts
. The railroads' stringent requirements for accurate watches to safely schedule trains drove improvements in accuracy. The engineer Webb C. Ball
, established around 1891 the first precision standards and a reliable timepiece inspection system for Railroad chronometers. Temperature compensated balance wheels began to be widely used in watches during this period, and jewel bearing
s became almost universal. Techniques for adjusting the balance spring for isochronism and positional errors discovered by Abraham-Louis Breguet, M. Phillips, and L. Lossier were adopted. The first international watch precision contest took place in 1876, during the International Centennial Exposition
in Philadelphia (the winning four top watches, which outclassed all competitors, had been randomly selected out of the mass production line), on display was also the first fully automatic screw making machine. By 1900, with these advances, the accuracy of quality watches, properly adjusted, topped out at a few seconds per day.
From about 1860, key winding was replaced by keyless winding, where the watch was wound by turning the crown. The pin pallet escapement, an inexpensive version of the lever escapement invented in 1876 by Georges Frederic Roskopf
was used in cheap mass produced dollar watch
es, which allowed ordinary workers to own a watch for the first time; other cheap watches used a simplifed version of the duplex escapement, developed by Daniel Buck
in the 1870s.
These improvements were mostly originated and applied in the United States, and as a result the American industry ousted that of Switzerland from its long-held position as worldwide leader in the low-to-middle-class market. The Swiss responded, towards the end of the century, by changing their emphasis from economy to quality.
and elinvar
. A balance wheel of invar with a spring of elinvar was almost unaffected by temperature changes, so it replaced the complicated temperature compensated balance. The discovery in 1903 of a process to produce artificial sapphire
made jewelling
cheap. Bridge construction superseded 3/4 plate construction.
) developed a concept of wristwatches, made for German naval officers and ordered by Kaiser Wilhelm I of Germany. Two-thousand watches were produced, which represents the first important commercialization of wristwatches. For civilians the wristwatches did not yet become popular among men. At the beginning of the century wristwatches were mostly worn by women.
In 1904, Brazilian aviator Alberto Santos Dumont asked his friend Louis Cartier
to come up with an alternative that would allow him to keep both hands on the controls while timing his performances during flight. Cartier and his master watchmaker, Edmond Jaeger soon came up with the first prototype for a man's wristwatch called the Santos wristwatch. The Santos first went on sale in 1911, the date of Cartier's first production of wristwatches.
During the First World War soldiers needed access to their watches while their hands were full. They were given wristwatches, called 'trench watches', which were made with pocketwatch movements, so they were large and bulky and had the crown at the 12 o'clock position like pocketwatches. After the war pocketwatches went out of fashion and by 1930 the ratio of wrist- to pocketwatches was 50 to 1. The first successful self-winding system was invented by John Harwood in 1923.
, or in a few advanced watches that foreshadowed the quartz watch, by a steel tuning fork
vibrating at 360 Hz
, powered by a solenoid driven by a transistor oscillator
circuit. The hands were still moved mechanically by a wheel train
. In mechanical watches the self winding mechanism, shockproof balance pivots, and break resistant 'white metal' mainspring
s became standard. The jewel craze caused 'jewel inflation' and watches with up to 100 jewels were produced.
resonator
which vibrated at 8,192 Hz, driven by a battery powered oscillator circuit
. In place of a wheel train
to add up the beats into seconds, minutes, and hours, it used digital counters. The higher Q factor
of the resonator, along with quartz's low temperature coefficient, resulted in better accuracy than the best mechanical watches, while the elimination of all moving parts made the watch more shock-resistant and eliminated the need for periodic cleaning.
Accuracy increased with the frequency of the crystal used, but so did power consumption. So the first generation watches had low frequencies of a few kilohertz, limiting their accuracy. The power saving use of CMOS
logic and LCD displays in the 2nd generation increased battery life and allowed the crystal frequency
to be increased to 32,768 Hz resulting in accuracy of 5–10 seconds per month. By the 1980s, quartz watches had taken over most of the watch market from the mechanical watch industry.
offered the first radio-controlled
wristwatch, the MEGA 1. In this type, the watch's quartz oscillator is set to the correct time daily by coded radio time signals broadcast by government-operated time stations such as WWVH
, received by a radio receiver in the watch. This allows the watch to have the same long-term accuracy as the atomic clock
s which control the time signals. Recent models are capable of receiving synchronization signals from various time stations worldwide. This also included some televisions and vcr players.
Watch
A watch is a small timepiece, typically worn either on the wrist or attached on a chain and carried in a pocket, with wristwatches being the most common type of watch used today. They evolved in the 17th century from spring powered clocks, which appeared in the 15th century. The first watches were...
es evolved from portable spring driven clocks, which first in the 15th century. Portable timepieces were made possible by the invention 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...
. Although some sources erroneously credit Nuremberg
Nuremberg
Nuremberg[p] is a city in the German state of Bavaria, in the administrative region of Middle Franconia. Situated on the Pegnitz river and the Rhine–Main–Danube Canal, it is located about north of Munich and is Franconia's largest city. The population is 505,664...
clockmaker Peter Henlein
Peter Henlein
Peter Henlein , a locksmith and watchmaker from Nuremberg, is often considered the inventor of the portable timekeeper, making him the inventor of the watch, but this claim is disputed...
(or Henle or Hele) with inventing the mainspring around 1511, many references to 'clocks without weights' and two surviving examples show that spring powered clocks appeared in the 15th century. Henlein is also often credited with constructing the first pocketwatches, mostly because of a passage by Johann Cochläus in 1511:
Peter Hele, still a young man, fashions works which even the most learned mathematicians admire. He shapes many-wheeled clocks out of small bits of iron, which run and chime the hours without weights for forty hours, whether carried at the breast or in a handbag
and because he was popularized in a 19th century novel. However, many German clockmakers were creating miniature timepieces during this period, and there is no evidence Henlein was the first. Also, watches weren't widely worn in pockets until the 17th century.
1500–1600 Clock-watches
The first timepieces to be worn, made in 16th century Europe, were transitional in size between clocks and watches. These 'clock-watches' were fastened to clothing or worn on a chain around the neck. They were heavy drum shaped cylindrical brass boxes several inches in diameter, engraved and ornamented. They had only an hour handClock face
A clock face is the part of an analog clock that displays the time through the use of a fixed numbered dial or dials and moving hands. In its most basic form, recognized universally throughout the world, the dial is numbered 1–12 indicating the hours in a 12-hour cycle, and a short hour hand...
. The face was not covered with glass, but usually had a hinged brass cover, often decoratively pierced with grillwork so the time could be read without opening. The movement was made of iron or steel and held together with tapered pins and wedges, until screws began to be used after 1550. Many of the movements included striking
Striking clock
A striking clock is a clock that sounds the hours audibly on a bell or gong. In 12 hour striking, used most commonly in striking clocks today, the clock strikes once at 1 AM, twice at 2 AM, continuing in this way up to twelve times at 12 noon, then starts over, striking once at 1 PM, twice at 2...
or alarm
Alarm clock
An alarm clock is a clock that is designed to make a loud sound at a specific time. The primary use of these clocks is to awaken people from their night's sleep or short naps; they are sometimes used for other reminders as well. To stop the sound, a button or handle on the clock is pressed; but...
mechanisms. They usually had to be wound twice a day. The shape later evolved into a rounded form; these were called Nuremberg eggs. Still later in the century there was a trend for unusually shaped watches, and clock-watches shaped like books, animals, fruit, stars, flowers, insects, crosses, and even skulls (Death's head watches) were made.
It should not be thought that the reason for wearing these early clock-watches was to tell the time. The accuracy of their verge and foliot movements was so poor, perhaps several hours per day, that they were practically useless. They were made as jewelry and novelties for the nobility
Nobility
Nobility is a social class which possesses more acknowledged privileges or eminence than members of most other classes in a society, membership therein typically being hereditary. The privileges associated with nobility may constitute substantial advantages over or relative to non-nobles, or may be...
, valued for their fine ornamentation, unusual shape, or intriguing mechanism, and accurate timekeeping was of very minor importance.
1600–1657 Pocketwatches
Styles changed in the 17th century and men began to wear watches in pockets instead of as pendantPendant
A pendant is a loose-hanging piece of jewellery, generally attached by a small loop to a necklace, when the ensemble may be known as a "pendant necklace". A pendant earring is an earring with a piece hanging down. In modern French "pendant" is the gerund form of “hanging”...
s (the woman's watch remained a pendant into the 20th century). This is said to have occurred in 1675 when Charles II of England
Charles II of England
Charles II was monarch of the three kingdoms of England, Scotland, and Ireland.Charles II's father, King Charles I, was executed at Whitehall on 30 January 1649, at the climax of the English Civil War...
introduced waistcoat
Waistcoat
A waistcoat or vest is a sleeveless upper-body garment worn over a dress shirt and necktie and below a coat as a part of most men's formal wear, and as the third piece of the three-piece male business suit.-Characteristics and use:...
s. To fit in pockets, their shape evolved into the typical pocketwatch shape, rounded and flattened with no sharp edges. Glass was used to cover the face beginning around 1610. Watch fobs began to be used, the name originating from the German word fuppe, a small pocket. The watch was wound and also set by opening the back and fitting a key to a square arbor, and turning it.
The timekeeping mechanism in these early pocketwatches was the same one used in clocks, invented in the 13th century; the verge escapement
Verge escapement
The verge escapement is the earliest known type of mechanical escapement, the mechanism in a mechanical clock that controls its rate by advancing the gear train at regular intervals or 'ticks'. Its origin is unknown. Verge escapements were used from the 14th century until about 1800 in clocks...
which drove a foliot
Foliot
A foliot may refer to:* Part of the verge escapement for early clocks* A creature of Italian folklore , as recorded by Gerolamo Cardano and Robert Burton...
, a dumbbell
Dumbbell
The dumbbell, a type of free weight, is a piece of equipment used in weight training. It can be used individually or in pairs .-History:...
shaped bar with weights on the ends, to oscillate back and forth. However, 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...
introduced a source of error not present in weight-powered clocks. The force provided by a spring
Spring (device)
A spring is an elastic object used to store mechanical energy. Springs are usually made out of spring steel. Small springs can be wound from pre-hardened stock, while larger ones are made from annealed steel and hardened after fabrication...
is not constant, but decreases as the spring unwinds. The rate of all timekeeping mechanisms is affected by changes in their drive force, but the primitive verge and foliot mechanism was especially sensitive to these changes, so early watches slowed down during their running period as the mainspring ran down. This problem, called lack of isochronism
Isochronous
Isochronous : From Greek iso, equal + chronos, time. It literally means regularly, or at equal time intervals. In general English language, it refers to something that occurs at a regular interval, of the same duration; as opposed to synchronous which refers to more than one thing happening at the...
, plagued mechanical watches throughout their history.
Efforts to improve the accuracy of watches prior to 1657 focused on evening out the steep torque
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....
curve of the mainspring. Two devices to do this had appeared in the first clock-watches: the stackfreed and the fusee. The stackfreed, a spring-loaded cam
Cam
A cam is a rotating or sliding piece in a mechanical linkage used especially in transforming rotary motion into linear motion or vice-versa. It is often a part of a rotating wheel or shaft that strikes a lever at one or more points on its circular path...
on the mainspring shaft, added a lot of friction and was abandoned after about a century. The fusee was a much more lasting idea. A curving conical pulley
Pulley
A pulley, also called a sheave or a drum, is a mechanism composed of a wheel on an axle or shaft that may have a groove between two flanges around its circumference. A rope, cable, belt, or chain usually runs over the wheel and inside the groove, if present...
with a chain wrapped around it attached to the mainspring barrel
Barrel
A barrel or cask is a hollow cylindrical container, traditionally made of vertical wooden staves and bound by wooden or metal hoops. Traditionally, the barrel was a standard size of measure referring to a set capacity or weight of a given commodity. A small barrel is called a keg.For example, a...
, it changed the leverage as the spring unwound, equalizing the drive force. Fusees became standard in all watches, and were used until the early 19th century. The foliot was also gradually replaced with the balance wheel
Balance wheel
The balance wheel is the timekeeping device used in mechanical watches and some clocks, analogous to the pendulum in a pendulum clock. It is a weighted wheel that rotates back and forth, being returned toward its center position by a spiral spring, the balance spring or hairspring...
, which had a higher moment of inertia
Moment of inertia
In classical mechanics, moment of inertia, also called mass moment of inertia, rotational inertia, polar moment of inertia of mass, or the angular mass, is a measure of an object's resistance to changes to its rotation. It is the inertia of a rotating body with respect to its rotation...
for its size, allowing better timekeeping.
1657–1765 The balance spring
A great leap forward in accuracy occurred in 1657 with the addition of the balance springBalance spring
A balance spring, or hairspring, is a part used in mechanical timepieces. The balance spring, attached to the balance wheel, controls the speed at which the wheels of the timepiece turn, and thus the rate of movement of the hands...
to the balance wheel, an invention disputed both at the time and ever since between Robert Hooke
Robert Hooke
Robert Hooke FRS was an English natural philosopher, architect and polymath.His adult life comprised three distinct periods: as a scientific inquirer lacking money; achieving great wealth and standing through his reputation for hard work and scrupulous honesty following the great fire of 1666, but...
and Christiaan Huygens. Prior to this, the only force limiting the back and forth motion of the balance wheel under the force of the escapement was the wheel's inertia
Inertia
Inertia is the resistance of any physical object to a change in its state of motion or rest, or the tendency of an object to resist any change in its motion. It is proportional to an object's mass. The principle of inertia is one of the fundamental principles of classical physics which are used to...
. This caused the wheel's period to be very sensitive to the force of the mainspring. The balance spring made the balance wheel a harmonic oscillator
Harmonic oscillator
In classical mechanics, a harmonic oscillator is a system that, when displaced from its equilibrium position, experiences a restoring force, F, proportional to the displacement, x: \vec F = -k \vec x \, where k is a positive constant....
, with a natural 'beat' resistant to disturbances. This increased watches' accuracy enormously, from perhaps several hours per day to perhaps 10 minutes per day, resulting in the addition of the minute hand
Clock face
A clock face is the part of an analog clock that displays the time through the use of a fixed numbered dial or dials and moving hands. In its most basic form, recognized universally throughout the world, the dial is numbered 1–12 indicating the hours in a 12-hour cycle, and a short hour hand...
to the face from around 1680 in Britain and 1700 in France. The increased accuracy of the balance wheel focused attention on errors caused by other parts of the movement
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...
, igniting a two century wave of watchmaking innovation. The first thing to be improved was the 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...
. The verge escapement was replaced in quality watches by the cylinder escapement, invented by Thomas Tompion
Thomas Tompion
Thomas Tompion was an English clock maker, watchmaker and mechanician who is still regarded to this day as the Father of English Clockmaking. Tompion's work includes some of the most historic and important clocks and watches in the world and can command very high prices whenever outstanding...
in 1695 and further developed by George Graham
George Graham (clockmaker)
George Graham was an English clockmaker, inventor, and geophysicist, and a Fellow of the Royal Society.He was born to George Graham in Kirklinton, Cumberland. A Friend like his mentor Thomas Tompion, Graham left Cumberland in 1688 for London to work with Tompion...
in the 1720s. In Britain a few quality watches went to the duplex escapement, invented by Jean Baptiste Dutertre in 1724. The advantage of these escapements was that they only gave the balance wheel a short push in the middle of its swing, leaving it 'detached' from the escapement to swing back and forth undisturbed during most of its cycle.
During the same period, improvements in manufacturing such as the tooth-cutting machine devised by Robert Hooke
Robert Hooke
Robert Hooke FRS was an English natural philosopher, architect and polymath.His adult life comprised three distinct periods: as a scientific inquirer lacking money; achieving great wealth and standing through his reputation for hard work and scrupulous honesty following the great fire of 1666, but...
allowed some increase in the volume of watch production, although finishing and assembling was still done by hand until well into the 19th century.
1765–1800 Temperature compensation and chronometers
The EnlightenmentAge of Enlightenment
The Age of Enlightenment was an elite cultural movement of intellectuals in 18th century Europe that sought to mobilize the power of reason in order to reform society and advance knowledge. It promoted intellectual interchange and opposed intolerance and abuses in church and state...
view of watches as scientific instruments brought rapid advances to their mechanisms. The development during this period of accurate marine chronometer
Marine chronometer
A marine chronometer is a clock that is precise and accurate enough to be used as a portable time standard; it can therefore be used to determine longitude by means of celestial navigation...
s to determine longitude
Longitude
Longitude is a geographic coordinate that specifies the east-west position of a point on the Earth's surface. It is an angular measurement, usually expressed in degrees, minutes and seconds, and denoted by the Greek letter lambda ....
during sea voyages produced many technological advances that were later used in watches. It was found that a major cause of error in balance wheel timepieces was changes in elasticity
Elasticity (physics)
In physics, elasticity is the physical property of a material that returns to its original shape after the stress that made it deform or distort is removed. The relative amount of deformation is called the strain....
of the balance spring
Balance spring
A balance spring, or hairspring, is a part used in mechanical timepieces. The balance spring, attached to the balance wheel, controls the speed at which the wheels of the timepiece turn, and thus the rate of movement of the hands...
with temperature changes. This problem was solved by the bimetallic temperature compensated balance wheel
Balance wheel
The balance wheel is the timekeeping device used in mechanical watches and some clocks, analogous to the pendulum in a pendulum clock. It is a weighted wheel that rotates back and forth, being returned toward its center position by a spiral spring, the balance spring or hairspring...
invented in 1765 by Pierre Le Roy
Pierre Le Roy
Pierre Le Roy was a French clockmaker. He was the inventor of the detent escapement, the temperature-compensated balance and the isochronous balance spring. His developments are considered as the foundation of the modern chronometer...
and improved by Thomas Earnshaw
Thomas Earnshaw
Thomas Earnshaw was an English watchmaker who following John Arnold's earlier work, further simplified the process of marine chronometer production, making them available to the general public...
. This type of balance wheel had two semicircular arms made of a bimetallic construction. If the temperature rose, the arms bent inward slightly, causing the balance wheel to rotate faster back and forth, compensating for the slowing due to the weaker balance spring. This system, which could reduce temperature induced error to a few seconds per day, gradually began to be used in watches over the next hundred years.
The going barrel invented in 1760 by Jean-Antoine Lépine
Jean-Antoine Lépine
Jean-Antoine Lépine , was a revolutionary and inventive French watch and clockmaker, who contributed with crucial inventions for watchmaking still used nowadays...
provided a more constant drive force over the watch's running period, and its adoption in the 19th century made the fusee
Fusee
Used in antique spring-powered mechanical watches and clocks, a fusee is a cone-shaped pulley with a spiral groove around it, wound with a cord or chain which is attached to the mainspring barrel...
obsolete. Complicated pocket chronometers and astronomical watches with many hands and functions were made during this period.
1800–1850 Lever escapement
The lever escapementLever escapement
The lever escapement is a key component of the typical movement found in most mechanical wristwatches, pocket watches and many small mechanical non-pendulum clocks....
, invented by Thomas Mudge in 1759 and improved by Josiah Emery in 1785, gradually came into use from about 1800 onwards, chiefly in Britain; it was also adopted by Abraham-Louis Breguet, but Swiss
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
watchmakers (who by now were the chief suppliers of watches to most of Europe) mostly adhered to the cylinder until the 1860s. By about 1900, however, the lever was used in almost every watch made. In this escapement the escape wheel pushed on a T shaped 'lever', which was unlocked as the balance wheel swung through its center position and gave the wheel a brief push before releasing it. The advantages of the lever was that it allowed the balance wheel to swing completely free during most of its cycle; due to 'locking' and 'draw' its action was very precise; and it was self-starting, so if the balance wheel was stopped by a jar it would start again. Jewel bearing
Jewel bearing
A jewel bearing is a plain bearing in which a metal spindle turns in a jewel-lined pivot hole. The hole is typically shaped like a torus and is slightly larger than the shaft diameter. The jewel material is usually synthetic sapphire...
s, introduced in 1702 by Nicolas Fatio de Duillier
Nicolas Fatio de Duillier
Nicolas Fatio de Duillier was a Swiss mathematician known for his work on the zodiacal light problem, for his very close relationship with Isaac Newton, for his role in the Newton v. Leibniz calculus controversy, and for originating the "push" or "shadow" theory of gravitation...
, also came into use for quality watches during this period.
Watches of this period are characterised by their thinness. New innovations, such as the cylinder and lever escapements, allowed watches to become much thinner that they had previously been. This was also in accordance with a change in fashion. Deep, verge movements were no longer attractive, hence the arrival of the epithet 'Onion'.
1850–1900 Mass production
At Vacheron Constantin, Geneva, Georges-Auguste Leschot (1800–1884), pioneered in the field of interchangeability in clockmaking by the invention of various machine tools. 1830 he designed an anchor escapement, which his student, Antoine Léchaud, later mass produced. 1839 he invented a pantographPantograph
A pantograph is a mechanical linkage connected in a special manner based on parallelograms so that the movement of one pen, in tracing an image, produces identical movements in a second pen...
allowing some degree of standardisation and interchangeability of parts on watches fitted with the same calibre.
Watch manufacturing really changed from assembly in watchmaking shops to mass production
Mass production
Mass production is the production of large amounts of standardized products, including and especially on assembly lines...
with interchangeable parts
Interchangeable parts
Interchangeable parts are parts that are, for practical purposes, identical. They are made to specifications that ensure that they are so nearly identical that they will fit into any device of the same type. One such part can freely replace another, without any custom fitting...
, as from 1854, pioneered by the Waltham Watch Company
Waltham Watch Company
The Waltham Watch Company, also known as the American Waltham Watch Co. and the American Watch Co., produced about 40 million high quality watches, clocks, speedometers, compasses, time fuses and other precision instruments between 1850 and 1957...
, in Waltham, Massachusetts
Waltham, Massachusetts
Waltham is a city in Middlesex County, Massachusetts, United States, was an early center for the labor movement, and major contributor to the American Industrial Revolution. The original home of the Boston Manufacturing Company, the city was a prototype for 19th century industrial city planning,...
. The railroads' stringent requirements for accurate watches to safely schedule trains drove improvements in accuracy. The engineer Webb C. Ball
Webb C. Ball
Webster Clay Ball was a jeweler and watchmaker born in Fredericktown, Ohio. After a two-year apprenticeship to a jeweler, Ball settled in Cleveland, Ohio to join a jewelry store...
, established around 1891 the first precision standards and a reliable timepiece inspection system for Railroad chronometers. Temperature compensated balance wheels began to be widely used in watches during this period, and jewel bearing
Jewel bearing
A jewel bearing is a plain bearing in which a metal spindle turns in a jewel-lined pivot hole. The hole is typically shaped like a torus and is slightly larger than the shaft diameter. The jewel material is usually synthetic sapphire...
s became almost universal. Techniques for adjusting the balance spring for isochronism and positional errors discovered by Abraham-Louis Breguet, M. Phillips, and L. Lossier were adopted. The first international watch precision contest took place in 1876, during the International Centennial Exposition
Centennial Exposition
The Centennial International Exhibition of 1876, the first official World's Fair in the United States, was held in Philadelphia, Pennsylvania, from May 10 to November 10, 1876, to celebrate the 100th anniversary of the signing of the Declaration of Independence in Philadelphia. It was officially...
in Philadelphia (the winning four top watches, which outclassed all competitors, had been randomly selected out of the mass production line), on display was also the first fully automatic screw making machine. By 1900, with these advances, the accuracy of quality watches, properly adjusted, topped out at a few seconds per day.
From about 1860, key winding was replaced by keyless winding, where the watch was wound by turning the crown. The pin pallet escapement, an inexpensive version of the lever escapement invented in 1876 by Georges Frederic Roskopf
Georges Frederic Roskopf
Georges F. Roskopf , the inventor of the pin-pallet escapement, was born in Germany and became a naturalized Swiss citizen.- Early life and introduction :...
was used in cheap mass produced dollar watch
Dollar watch
A dollar watch was a pocket watch or later, a wristwatch, that sold for about one dollar.The sale of such watches began in 1892 by the watchmakers Ingersoll Watch Company, Waterbury Clock Company, and New Haven. Later, Western Clock in 1899 and the E. Ingraham Company also began manufacturing them...
es, which allowed ordinary workers to own a watch for the first time; other cheap watches used a simplifed version of the duplex escapement, developed by Daniel Buck
Daniel Buck
Daniel Buck was a United States Representative from Vermont. Born in Hebron, Connecticut, he studied law, was admitted to the bar in 1783 and practiced in Thetford, Vermont. He was prosecuting attorney of Orange County from 1783 to 1785 and was clerk of the court in 1783 and 1784...
in the 1870s.
These improvements were mostly originated and applied in the United States, and as a result the American industry ousted that of Switzerland from its long-held position as worldwide leader in the low-to-middle-class market. The Swiss responded, towards the end of the century, by changing their emphasis from economy to quality.
1900–1920 Better materials
During the 20th century, the mechanical design of the watch became standardized, and advances were made in better materials, tighter tolerances, and improved production methods. The bimetallic temperature compensated balance wheel was made obsolete by the discovery of low temperature coefficient alloys invarInvar
Invar, also known generically as FeNi36 , is a nickel steel alloy notable for its uniquely low coefficient of thermal expansion . The name, Invar, comes from the word invariable, referring to its lack of expansion or contraction with temperature changes.It was invented in 1896 by Swiss scientist...
and elinvar
Elinvar
Elinvar is a nickel steel alloy with a modulus of elasticity which does not change much with temperature changes. The name is a contraction of the French elasticité invariable. It was invented in the late 1890s by Charles Édouard Guillaume, a Swiss physicist who also invented Invar, another...
. A balance wheel of invar with a spring of elinvar was almost unaffected by temperature changes, so it replaced the complicated temperature compensated balance. The discovery in 1903 of a process to produce artificial sapphire
Sapphire
Sapphire is a gemstone variety of the mineral corundum, an aluminium oxide , when it is a color other than red or dark pink; in which case the gem would instead be called a ruby, considered to be a different gemstone. Trace amounts of other elements such as iron, titanium, or chromium can give...
made jewelling
Jewel bearing
A jewel bearing is a plain bearing in which a metal spindle turns in a jewel-lined pivot hole. The hole is typically shaped like a torus and is slightly larger than the shaft diameter. The jewel material is usually synthetic sapphire...
cheap. Bridge construction superseded 3/4 plate construction.
1920–1950 Wristwatches become popular
Patek Phillipe created the first wristwatch in 1868. In 1880 Constant Girard (Girard-PerregauxGirard-Perregaux
Girard-Perregaux is a high-end Swiss watch manufacture with its origins dating back to 1791. It is situated in La Chaux-de-Fonds, Switzerland and is a part of the Sowind group, a subsidiary of PPR.- History :...
) developed a concept of wristwatches, made for German naval officers and ordered by Kaiser Wilhelm I of Germany. Two-thousand watches were produced, which represents the first important commercialization of wristwatches. For civilians the wristwatches did not yet become popular among men. At the beginning of the century wristwatches were mostly worn by women.
In 1904, Brazilian aviator Alberto Santos Dumont asked his friend Louis Cartier
Louis Cartier
Louis Cartier was a famous French watchmaker and businessman known worldwide for elegant and extravagant watch designs. He was passionate about mechanical pocket watches and had the goal of creating his own line of timepieces...
to come up with an alternative that would allow him to keep both hands on the controls while timing his performances during flight. Cartier and his master watchmaker, Edmond Jaeger soon came up with the first prototype for a man's wristwatch called the Santos wristwatch. The Santos first went on sale in 1911, the date of Cartier's first production of wristwatches.
During the First World War soldiers needed access to their watches while their hands were full. They were given wristwatches, called 'trench watches', which were made with pocketwatch movements, so they were large and bulky and had the crown at the 12 o'clock position like pocketwatches. After the war pocketwatches went out of fashion and by 1930 the ratio of wrist- to pocketwatches was 50 to 1. The first successful self-winding system was invented by John Harwood in 1923.
1950–1969 Electric watches
The first generation electric-powered watches came out during this period. These kept time with a balance wheel powered by a solenoidSolenoid
A solenoid is a coil wound into a tightly packed helix. In physics, the term solenoid refers to a long, thin loop of wire, often wrapped around a metallic core, which produces a magnetic field when an electric current is passed through it. Solenoids are important because they can create...
, or in a few advanced watches that foreshadowed the quartz watch, by a steel tuning fork
Tuning fork
A tuning fork is an acoustic resonator in the form of a two-pronged fork with the prongs formed from a U-shaped bar of elastic metal . It resonates at a specific constant pitch when set vibrating by striking it against a surface or with an object, and emits a pure musical tone after waiting a...
vibrating at 360 Hz
Hertz
The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....
, powered by a solenoid driven by a transistor oscillator
Electronic oscillator
An electronic oscillator is an electronic circuit that produces a repetitive electronic signal, often a sine wave or a square wave. They are widely used in innumerable electronic devices...
circuit. The hands were still moved mechanically by a wheel train
Wheel train (horology)
In horology, a wheel train is the gear train of a mechanical watch or clock. Although the term is used for other types of gear trains, the long history of mechanical timepieces has created a traditional terminology for their gear trains which is not used in other applications of gears.Watch...
. In mechanical watches the self winding mechanism, shockproof balance pivots, and break resistant 'white metal' 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...
s became standard. The jewel craze caused 'jewel inflation' and watches with up to 100 jewels were produced.
1969 Quartz watches
The introduction of the quartz watch in 1969 was a revolutionary improvement in watch technology. In place of a balance wheel which oscillated at 5 beats per second, it used a quartz crystalCrystal 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...
resonator
Resonator
A resonator is a device or system that exhibits resonance or resonant behavior, that is, it naturally oscillates at some frequencies, called its resonant frequencies, with greater amplitude than at others. The oscillations in a resonator can be either electromagnetic or mechanical...
which vibrated at 8,192 Hz, driven by a battery powered oscillator circuit
Electronic oscillator
An electronic oscillator is an electronic circuit that produces a repetitive electronic signal, often a sine wave or a square wave. They are widely used in innumerable electronic devices...
. In place of a wheel train
Wheel train (horology)
In horology, a wheel train is the gear train of a mechanical watch or clock. Although the term is used for other types of gear trains, the long history of mechanical timepieces has created a traditional terminology for their gear trains which is not used in other applications of gears.Watch...
to add up the beats into seconds, minutes, and hours, it used digital counters. The higher Q factor
Q factor
In physics and engineering the quality factor or Q factor is a dimensionless parameter that describes how under-damped an oscillator or resonator is, or equivalently, characterizes a resonator's bandwidth relative to its center frequency....
of the resonator, along with quartz's low temperature coefficient, resulted in better accuracy than the best mechanical watches, while the elimination of all moving parts made the watch more shock-resistant and eliminated the need for periodic cleaning.
Accuracy increased with the frequency of the crystal used, but so did power consumption. So the first generation watches had low frequencies of a few kilohertz, limiting their accuracy. The power saving use of CMOS
CMOS
Complementary metal–oxide–semiconductor is a technology for constructing integrated circuits. CMOS technology is used in microprocessors, microcontrollers, static RAM, and other digital logic circuits...
logic and LCD displays in the 2nd generation increased battery life and allowed the crystal frequency
Frequency
Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...
to be increased to 32,768 Hz resulting in accuracy of 5–10 seconds per month. By the 1980s, quartz watches had taken over most of the watch market from the mechanical watch industry.
1990 Radio controlled
In 1990, JunghansJunghans
Junghans Uhren GmbH is Germany's largest watch and clock manufacturer.The company is located in Schramberg, Baden-Württemberg. On 15 April 1861 Erhard Junghans created the company „Junghans und Tobler“ together with his brother-in-law Jakob Zeller-Tobler in Schramberg .The company began to produce...
offered the first radio-controlled
Radio clock
A radio clock or radio-controlled clock is a clock that is synchronized by a time code bit stream transmitted by a radio transmitter connected to a time standard such as an atomic clock...
wristwatch, the MEGA 1. In this type, the watch's quartz oscillator is set to the correct time daily by coded radio time signals broadcast by government-operated time stations such as WWVH
WWVH
WWVH is the callsign of the U.S. National Institute of Standards and Technology's shortwave radio time signal station in Kekaha, on the island of Kauai in the state of Hawaii....
, received by a radio receiver in the watch. This allows the watch to have the same long-term accuracy as the atomic clock
Atomic clock
An atomic clock is a clock that uses an electronic transition frequency in the microwave, optical, or ultraviolet region of the electromagnetic spectrum of atoms as a frequency standard for its timekeeping element...
s which control the time signals. Recent models are capable of receiving synchronization signals from various time stations worldwide. This also included some televisions and vcr players.
See also
- BreitlingBreitlingBreitling is a luxury brand of Swiss watches produced by Breitling SA, a private company headquartered in Grenchen, Canton of Solothurn . The company exclusively offered Certified Chronometers in all models since 2000...
- Fortis Uhren AGFortis Uhren AGFortis is a watchmaker founded and based in Grenchen Switzerland that was established by Walter Vogt in 1912.- History :12 years after its establishment, Walter Vogt set up production with John Harwood, the inventor of the automatic wristwatch. In 1926, Fortis released the first self-winding...
- IWCInternational Watch CompanyInternational Watch Co, also known as IWC, is a high-end Swiss watch manufacturer located in Schaffhausen, Switzerland. IWC is an active member of the Federation of the Swiss Watch Industry FH....
- LonginesLonginesLongines is a Swiss luxury watchmaker based in Saint-Imier, Switzerland. The company was originally founded by Auguste Agassiz in 1832 and it currently holds the oldest registered logo for a watch company . Longines is currently owned by the Swatch Group.Longines is known for its 'Aviators' watches...
- History of timekeeping devicesHistory of timekeeping devicesFor thousands of years, devices have been used to measure and keep track of time. The current sexagesimal system of time measurement dates to approximately 2000 BC, in Sumer. The Ancient Egyptians divided the day into two 12-hour periods, and used large obelisks to track the movement of the Sun...
- Zeno-Watch BaselZeno-Watch BaselZeno-Watch is a Swiss watchmaker in business since 1868, but only using the Zeno name since 1922. Specializing in aviation watches, they exist today as one of the few independent Swiss watch manufacturers still in operation, and make watches in their factory in Basel, Switzerland.Zeno's history...
- HorologyHorologyHorology is the art or science of measuring time. Clocks, watches, clockwork, sundials, clepsydras, timers, time recorders and marine chronometers are all examples of instruments used to measure time.People interested in horology are called horologists...
External links
- Functioning of a simple mechanical watch
- www.obidwat.com