A mainspring is a long, elastic, coiled strip of steel. Main springs were first used to store energy for mechanical clocks during the 15th century. A mainspring is wound inside a barrel. The torque provided by a mainspring is greatest when it is fully wound. As the spring gradually loosens, its torque continuously decreases, which has a negative effect on the speed of the watch. A self-winding watch regularly tightens its mainspring. This leads to a relatively constant torque level and thus a regular speed. Modern wristwatches generally use mainsprings made of "nivaflex," a special alloy that can be used to make a durable elastic spring that is highly resistant to breakage. The S-shaped "nivaflex" spring releases its energy reserve on a regular basis.

Vacheron Constantin's trademark is in the shape of a Maltese cross. A similarly shaped component is used to limit the extent to which the barrel can be wound. Together with a finger mounted on the barrel shaft, the Maltese cross compensates for major torque differences in the ignition of mechanical and gear-driven watches. This elaborate technique is only rarely used nowadays and is only found in particularly fine watches.

According to the unwritten laws of watchmaking, a company that makes watches can only call itself a "manufacture" if it makes at least one ebauche (vacuum movement). Companies whose craftsmen assemble ready-made ébauches to produce finished watches are known in the industry as "établisseures." The small, elite circle of mechanical watch manufactures currently includes Audemars Piguet, Chopard, Roger Dubuis, Girard-Perregaux, Glashütte Original, IWC, Jaeger-LeCoultre, A. Lange & Söhne, Patek Philippe, Piaget, Rolex, and Zenith, among other names.

As a watchmaker jargon, the French word for "marriage" describes the compilation of many authentic components taken from several different watches that are assembled in order to create a entirely new watch. Well-made mariages are difficult to identify, but even successful ones significantly reduce the value of a watch.

A clock or watch powered by a spring or descending weight. Speed regulation of these timepieces is reached with the balance of wheel and a spiral or an oscillating pendulum. The development of the mechanical gear train clock probably resulted from the mechanism used to drive planetaria, i.e., devices representing the motion of the planets. The earliest artifacts date back to the late 13th century. The oldest mechanical gear train clock in German-speaking Europe is probably the Strasbourg cathedral clock; this clock was completed in 1352. Functional gear train clocks first appeared in England in the late 13th century.

A unit of frequency indicating one million cycles per second.

A rotor, integrated into the movement plane, that automatically winds the mainspring of a self-winding watch. The motivation behind the invention of micro-rotor gauges was the desire to build very thin and therefore very elegant self-winding wristwatches. Building on old-fashioned hammer-style oscillating weights (moving only through an arc rather than completing a complete circle) or relying on central rotors, Universal Genève followed suit in 1958 with the slim "Polerouter." Piaget introduced the Caliber 12 Pl in 1959: just 2.3 mm thick, it was the thinnest automatic watch in the world. Patek Philippe's classic Caliber 240, 2.4 mm thin, has a micro-rotor made of 22-carat gold. Chopard's LUC 1.96 debuted in 1996: this in-house caliber has double barrels, is 3. 3 mm thick (including the jump date display) and has a power reserve of about 70 hours. are both located in a plane above the movement plane and are consequently thicker than micro-rotor calibres. Micro-rotor calibres have not captured a very large share of the market, but they have nevertheless become a fixed feature in watch technology. The pioneer of the micro-rotor was Büren Watch Co. which received a corresponding patent in 1954. Three years later, this company debuted its "Super Slender," which was only 4.2 mm thick, but they still became a fixed feature in watch technology. The pioneer of the micro-rotor was Büren Watch Co. which received a corresponding patent in 1954. Three years later, this company debuted its "Super Slender," which had a thickness of only 4.2 mm. but still became a fixed feature in watch technology. The pioneer of the micro-rotor was Büren Watch Co. which received a corresponding patent in 1954. Three years later, this company debuted its "Super Slender," which was only 4.2 mm thick.

One millionth of a meter or one thousandth of a millimeter. The thickness of gold plating on double watch cases is measured in microns, abbreviated by the Greek letter mu (µ). The double had a thickness of at least twenty microns. Nowadays five microns is a more common thickness.

With the introduction of mechanical geared clocks, the " civil" day was divided into 24 hours of equal length. The word "minute" comes from the Latin phrase "diminutiva pars," meaning "a diminished part of a whole." The Babylonians pioneered the sexagesimal system, which is based on the number "60."

Chronometers and chronographs often have a counter to calculate the number of minutes that have elapsed since the start of a stop time sequence. Counters that total up to a maximum of 30 or 45 minutes are the most common. These can be found, for example, on chronographs used by referees officiating at football matches. Other counters may count a maximum of only 15 or a maximum of 60 minutes. When the seconds hand of the chronograph or chronometer is returned to its zero position, the hand of the minute counter also returns to its original position.

Minute repeater watches strike one or more chimes to audibly announce the hours, quarter hours, and number of minutes elapsed since the last quarter hour. Their very complicated movements usually have two hammers striking two gongs. Each full hour is announced by the sound of the hammer with a corresponding number of strikes against a low gong. Minutes resound from a higher gong. Quarter hours are announced by double strikes (high low). The first minute repeater timepieces were made around 1750. They were and still are the glory in the art of creating repeater trains.

A group of constructions. Among other applications, modules are used in many self-winding chronographs. They are typically mounted on the front (dial side) of the movement. A friction joint is usually used to connect the module with the energy flow moving through the gear train. Modular constructions can usually be recognized without opening the case by the date window, which tends to be deeper below the dial and usually has a magnifying glass integrated into the glass above it, and by the V-shaped arrangement of the pushers and crown . Modules are also found in calendar watches, mainly on models that have so-called "perpetual calendars." In such watches, the entire calendar mechanism is mounted on its own plate, which is attached to the side of the movement dial. There are also strike train modules.

An indicator showing the number of days since the last full moon. In a synodic month, the interval from one new moon to another is exactly 29 days, 12 hours, 44 minutes and 3 seconds. The typical lunar phase displays are made up of a disk, cut around its periphery with 59 teeth and with two full moons printed or painted diametrically opposite each other on its surface. Powered by motion, this display requires two lunations to complete a full rotation around its axis. The current moon phase can be determined by looking through a specially cut shaped opening in the dial. A correspondingly divided scale surrounds the periphery of the moon phase indication. Views of the age of the moon deviate from astronomical reality by about eight hours per year.

As a result of cyclical changes in the positions of the sun, moon and Earth, the moon appears to pass through four phases (new moon, first quarter, full moon and last quarter) before returning to the new moon. The time elapsing from one new moon to the next is approximately 29.5 days.

A gear train located between the plate and the dial. It transmits and translates the rotation of the minute pinion into the hour hand. In addition, in combination with the hand adjustment system, the dial train allows the positions of the hour hand and minute hand to be exactly reset after the crown has been partially pulled out.

French watchmakers use this term to refer to the movement of a watch.

French term for a watch that is as transparent as possible and in which neither the movement nor the means of propulsion are visible.