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An automatic watch, also known as a self-winding watch or simply an automatic, is a mechanical watch where the natural motion of the wearer provides energy to wind the mainspring, making manual winding unnecessary if worn enough. [1] It is distinguished from a manual watch in that a manual watch must have its mainspring wound by hand at regular intervals.
In a mechanical watch the watch's gears are turned by a spiral spring called a mainspring. In a manual watch, energy is stored in the mainspring by turning a knob, the crown, on the side of the watch. Then the energy from the mainspring powers the watch movement until it runs down, requiring the spring to be wound again.
A self-winding watch movement has a mechanism which winds the mainspring using the natural motions of the wearer's body. [2] The watch contains an oscillating weight that turns on a pivot. [3] The normal movements of the watch in the user's pocket (for a pocketwatch) or on the user's arm (for a wristwatch) cause the rotor to pivot on its staff, which is attached to a ratcheted winding mechanism. [4] The motion of the watch is thereby translated into circular motion of the weight which, through a series of reverser and reducing gears, eventually winds the mainspring. There are many different designs for modern self-winding mechanisms. Some designs allow winding of the watch to take place while the weight swings in only one direction while other, more advanced, mechanisms have two ratchets and wind the mainspring during both clockwise and anti-clockwise weight motions.
The fully wound mainspring in a typical watch can store enough energy reserve for roughly two days, allowing the watch to keep running through the night while stationary. In many cases automatic wristwatches can also be wound manually by turning the crown, so the watch can be kept running when not worn, and in case the wearer's wrist motions are not sufficient to keep it wound automatically. [lower-alpha 1]
Self-winding mechanisms continue working even after the mainspring is fully wound up. If a simple mainspring was used, this would put excessive tension on the mainspring. This could break the mainspring, and even if it did not, it can cause a problem called "knocking" or "banking". The excessive drive force applied to the watch movement gear train can make the balance wheel rotate with excessive amplitude, causing the impulse pin to hit the back of the pallet fork horns. This will make the watch run fast, and could break the impulse pin. To prevent this, a slipping clutch device is used on the mainspring so it cannot be overwound.
The "slipping mainspring" device was patented by Adrien Philippe, one of the founders of Patek Philippe, on 16 June 1863, [5] long before self-winding wristwatches. In an ordinary watch mainspring barrel, the outer end of the spiral mainspring is attached to the inside of the barrel. In the slipping barrel, the mainspring is attached to a circular steel expansion spring, often called the 'bridle', which presses against the inside wall of the barrel, which has serrations or notches to hold it. [6]
As long as the mainspring is less than fully wound, the bridle holds the mainspring by friction to the barrel wall, allowing the mainspring to be wound. When the mainspring reaches full wind, its force is stronger than the bridle spring, and further winding pulls the bridle loose from the notches and it simply slides along the wall, preventing the mainspring from being wound further. The bridle must grip the barrel wall with just the right force to allow the mainspring to wind fully but not overwind. If it grips too loosely, the bridle will begin to slip before the mainspring is fully wound, a defect known as 'mainspring creep' which results in a shortened reserve power time.
A further advantage of this device is that the mainspring cannot be broken by excessive manual winding. This feature is often described in watch company advertising as an "unbreakable mainspring".
The earliest reference to self-winding watches is at the end of 1773 when a newspaper reported that Joseph Tlustos had invented a watch that did not need to be wound. [7] But his idea was probably based on the myth of perpetual motion, and it is unlikely that it was a practical solution to the problem of self-winding watches. In 1776 Joseph Gallmayr also stated that he had made a self-winding watch, but there is no evidence to support this claim.
The earliest credible evidence for a successful design is the watch made by the Swiss watchmaker Abraham-Louis Perrelet, who lived in Le Locle. In late 1776 or early 1777, he invented a self-winding mechanism for pocket watches but the original reports make no mention of the mechanism used, [8] although later evidence could point to a side weight type. [9] The Geneva Society of Arts, reporting on this watch in 1777, stated that 15 minutes walking was necessary to fully wind the watch.
In 1777 Abraham-Louis Breguet also became interested in the idea, and his first attempts led him to make a self-winding mechanism with a barrel remontoire. [10] Although a successful design, it was too complex and expensive for it to be manufactured and sold.
About the end of 1777 or early 1778, Hubert Sarton designed a watch with a rotor mechanism. Towards the end of 1778 he sent a watch to the French Academy of Sciences and a report was written which, together with a drawing, gave a detailed description of the mechanism. [11] Sarton's design is similar to those used in modern wrist watches, although there is no evidence linking the 18th-century design to 20th-century developments.
About the beginning of 1779, Abraham-Louis Breguet became aware of Perrelet's watches, probably through Louis Recordon, who travelled from Geneva to London via Le Locle and Paris. [12] Breguet studied and improved the design, and made many self-winding watches from then to about 1810.
Although a few self-winding watches and patents for them were made from 1780 on, for more than one hundred years these watches were rare, until the advent of the wrist watch.
During the years 1776 to 1810 four different types of weight were used:
As noted above, some watches used bidirectional winding and others used unidirectional winding. The latter is sufficient and all of Breguet's watches used unidirectional winding.
Before the invention of the slipping mainspring, automatic watches had a system for locking the weight. Most common, as in the 1780 drawing, when the mainspring was fully wound a lever K was raised that entered a hole N in the weight to prevent it from moving until the mainspring had unwound enough to lower the lever. Different methods were used in side-weight, rotor and center-weight mechanisms.
The advent of the wrist watch after World War I led to renewed interest in self-winding mechanisms, and all four types listed above were used:
Invented by John Harwood, a watch repairer from Bolton, England, who took out a UK patent with his financial backer, Harry Cutts, on 7 July 1923, and obtained a corresponding Swiss patent on 16 October 1923. [17] [18] The Harwood system used a pivoting weight which swung as the wearer moved, winding the mainspring. The ratchet mechanism wound the mainspring only when moving in one direction. The weight did not rotate a full 360°; spring bumpers limited its swing to about 180°, to encourage a back and forth motion. [19] This early type of self-winding mechanism is now referred to as a 'hammer' or 'bumper'. [20]
Like its 18th-century counterparts, Harwood's watch also had a problem with jerking because "the brass weight hit too sharply against the banking pins as it pivoted". [21]
When fully wound, Harwood's watch would run for 12 hours autonomously.[ citation needed ] It did not have a conventional stem winder, so the hands were moved manually by rotating a bezel around the face of the watch. The watches were first produced with the help of Swiss watch manufacturer Fortis and went on sale in 1928. Thirty thousand were made before the Harwood Self-Winding Watch Company collapsed in 1931 in the Great Depression. 'Bumper' watches were the first commercially successful automatic watches; they were made by several high grade watch manufacturers during the 1930s and 1940s.[ citation needed ]
The Rolex Watch Company improved Harwood's design in 1930 and used it as the basis for the Shants Company, in which the centrally mounted semi-circular weight could rotate through a full 360° rather than the about 200° of the 'bumper' winder. Rolex's version also increased the amount of energy stored in the mainspring, allowing it to run autonomously for up to 35 hours.
Information about 18th-century rotor watches was not published until 1949. Although the Oyster Perpetual was probably an original invention, the company may have known of Coviot's 1893 patent that re-invented the 18th-century design. [22]
With John Harwood's patent for self-winding watches set to expire in the early 1930s, Glycine founder Eugène Meylan started developing his own self-winding mechanism. Meylan’s design was unusual: a separate module that could be used with almost any 8.75 ligne (19.74 millimeter) watch movement. In October 1930, Glycine released their first automatic watches using this module, which became the world's first widely-produced automatic watches. This allowed Glycine to survive the global depression in the 1930s that caused many Swiss watchmakers to close shop. [23]
The next development for automatic watches came in 1948 from Eterna Watch. To wind a watch effectively, one of the chief requirements of a rotor is heft. Until this point, the best bearing used in any watch was a jewel bearing, which perfectly suits the small gears of a watch. A rotor, on the other hand, requires a different solution. In 1948, Eterna introduced the solution that is still in use today: ball bearings. Ball bearings provide robust support for a heavy object to rotate smoothly and reliably even under abnormal stress, such as if the watch were dropped. Eterna adopted geared bidirectional winding shortly afterwards.[ citation needed ]
By the 1960s, automatic winding had become widespread in quality mechanical watches. Because the rotor weight needed in an automatic watch takes up a lot of space in the case, increasing its thickness, some manufacturers of quality watches, such as Patek Philippe, continue to design manually wound watches, which can be as thin as 1.77 millimeters.
However, in 2007 Carl F. Bucherer implemented a new approach without a rotor, a peripherally mounted power source, where a geared ring and a rotating unbalance mass segment made of tungsten encircles the entire mechanism, rotating on carbon rollers whenever the watch moves. A system of clutch wheels captures power. No rotor means thinner watches and an ultradense weight swinging around a greater radius means a better chance of achieving a greater power reserve with same amount of arm movement. [24] [25]
A watch is a portable timepiece intended to be carried or worn by a person. It is designed to keep a consistent movement despite the motions caused by the person's activities. A wristwatch is designed to be worn around the wrist, attached by a watch strap or other type of bracelet, including metal bands, leather straps, or any other kind of bracelet. A pocket watch is designed for a person to carry in a pocket, often attached to a chain.
Clockwork refers to the inner workings of either mechanical devices called clocks and watches or other mechanisms that work similarly, using a series of gears driven by a spring or weight.
Rolex SA is a Swiss watch designer and manufacturer based in Geneva, Switzerland. Founded in 1905 as Wilsdorf and Davis by Hans Wilsdorf and Alfred Davis in London, the company registered Rolex as the brand name of its watches in 1908 and became Rolex Watch Co. Ltd. in 1915. After World War I, the company moved its base of operations to Geneva because of the unfavorable economy in the United Kingdom. In 1920, Hans Wilsdorf registered Montres Rolex SA in Geneva as the new company name ; it later became Rolex SA. Since 1960, the company has been owned by the Hans Wilsdorf Foundation, a private family trust.
A pocket watch is a watch that is made to be carried in a pocket, as opposed to a wristwatch, which is strapped to the wrist.
Seiko Group Corporation, commonly known as Seiko, is a Japanese maker of watches, clocks, electronic devices, semiconductors, jewelry, and optical products. Founded in 1881 by Kintarō Hattori in Tokyo, Seiko introduced the world's first commercial quartz wristwatch in 1969.
In horology, a movement, also known as a caliber or calibre, is the mechanism of a watch or timepiece, 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 clockwork movements are made of many moving parts. The movement of a digital watch is more commonly known as a module.
A mainspring is a spiral torsion spring of metal ribbon—commonly spring steel—used as a power source in mechanical watches, some clocks, and other clockwork mechanisms. 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 unwinds, until the next winding is needed. The adjectives wind-up and spring-powered refer to mechanisms powered by mainsprings, which also include kitchen timers, metronomes, music boxes, wind-up toys and clockwork radios.
In horology, a tourbillon is an addition to the mechanics of a watch escapement to increase accuracy. Conceived by the British watchmaker and inventor John Arnold, it was developed by his friend the Swiss-French watchmaker Abraham-Louis Breguet and patented by Breguet on 26 June 1801. In a tourbillon the escapement and balance wheel are mounted in a rotating cage, with the goal of eliminating errors of poise in the balance giving a uniform weight.
A fusee is a cone-shaped pulley with a helical groove around it, wound with a cord or chain attached to the mainspring barrel of antique mechanical watches and clocks. It was used from the 15th century to the early 20th century to improve timekeeping by equalizing the uneven pull of the mainspring as it ran down. Gawaine Baillie stated of the fusee, "Perhaps no problem in mechanics has ever been solved so simply and so perfectly."
The Hamilton Watch Company is a Swiss manufacturer of wristwatches based in Bienne, Switzerland. Founded in 1892 as an American firm, the Hamilton Watch Company ended American manufacture in 1969. Through a series of mergers and acquisitions, the Hamilton Watch Company eventually became integrated into the Swatch Group, the world's largest watch manufacturing and marketing conglomerate.
Spring Drive is a name given to a series of watch movements produced by Epson in Shiojiri. The concept of using a mainspring to power a quartz timing package was first conceived in 1977 by Yoshikazu Akahane at Suwa Seikosha. Specified to one second accuracy per day, the movement uses a conventional gear train as in traditional mechanical watches, but rather than an escapement and balance wheel, instead features Seiko's Tri-synchro Regulator system in which power delivery to the watch hands is regulated based on a reference quartz signal.
The history of watches began in 16th-century Europe, where watches evolved from portable spring-driven clocks, which first appeared in the 15th century.
An electric clock is a clock that is powered by electricity, as opposed to a mechanical clock which is powered by a hanging weight or a mainspring. The term is often applied to the electrically powered mechanical clocks that were used before quartz clocks were introduced in the 1980s. The first experimental electric clocks were constructed around the 1840s, but they were not widely manufactured until mains electric power became available in the 1890s. In the 1930s, the synchronous electric clock replaced mechanical clocks as the most widely used type of clock.
A power reserve indicator is a complication of the watch, which is designed to show the amount of remaining stored energy. The power reserve indicator indicates the tension on the mainspring at any particular moment.
A mechanical watch is a watch that uses a clockwork mechanism to measure the passage of time, as opposed to quartz watches which function using the vibration modes of a piezoelectric quartz tuning fork, or radio watches, which are quartz watches synchronized to an atomic clock via radio waves. A mechanical watch is driven by a mainspring which must be wound either periodically by hand or via a self-winding mechanism. Its force is transmitted through a series of gears to power the balance wheel, a weighted wheel which oscillates back and forth at a constant rate. A device called an escapement releases the watch's wheels to move forward a small amount with each swing of the balance wheel, moving the watch's hands forward at a constant rate. The escapement is what makes the 'ticking' sound which is heard in an operating mechanical watch. Mechanical watches evolved in Europe in the 17th century from spring powered clocks, which appeared in the 15th century.
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.
Abraham-Louis Perrelet was a Swiss horologist. He was born in Neuchâtel, then in the Principality of Neuchâtel.
John Harwood (1893–1964) was a British watchmaker who invented a self-winding wristwatch.
Memovox refers to a model series of mechanical wristwatches with alarm function of the Swiss watch manufacturer Jaeger-LeCoultre.
{{cite journal}}: Cite journal requires |journal= (help){{cite journal}}: Cite journal requires |journal= (help)The self-winding system was invented by John Harwood in 1923. It uses an oscillating weighted arm with two buffer springs. The wearer's movement causes the oscilllating arm to bump a ratchet that winds the watch.
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