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.
Mechanical watches are typically not as accurate as quartz watches, and they eventually require periodic cleaning and calibration by a skilled watchmaker. Since the 1970s, quartz watches have taken over most of the watch market, and mechanical watches are now mostly marketed as a luxury product, purchased for their aesthetic and luxury values, for appreciation of their fine craftsmanship, or as a status symbol.
The internal mechanism of a watch, excluding the face and hands, is called the movement. All mechanical watches have these five parts:
A mainspring, which stores mechanical energy to power the watch.
A gear train, called the wheel train, which has the dual function of transmitting the force of the mainspring to the balance wheel and adding up the swings of the balance wheel to get units of seconds, minutes, and hours. A separate part of the gear train, called the keyless work, allows the user to wind the mainspring and enables the hands to be moved to set the time.
A balance wheel, which oscillates back and forth. This is the timekeeping element in the watch.
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This is a collection of lectures on "structured innovation systems," codified approaches to stimulating and managing the process of innovation. Some of the systems to be covered may be Design Thinking
A marine chronometer is a precision timepiece that is carried on a ship and employed in the determination of the ship's position by celestial navigation. It is used to determine longitude by comparing Greenwich Mean Time (GMT), and the time at the current location found from observations of celestial bodies. When first developed in the 18th century, it was a major technical achievement, as accurate knowledge of the time over a long sea voyage was vital for effective navigation, lacking electronic or communications aids.
Bulova is an American timepiece manufacturing company that was founded in 1875 and has been owned by Japanese multinational conglomerate Citizen Watch Co. since 2008. The company makes watches, clocks and accessories, and it is based in New York City. Bulova was founded and incorporated as the J. Bulova Company in 1875 by Bohemian immigrant Joseph Bulova. It was reincorporated under the name Bulova Watch Company in 1923, became part of the Loews Corporation in 1979, and was sold to Citizen at the end of 2007.
A chronometer (χρονόμετρον, khronómetron, "time measurer") is an extraordinarily accurate mechanical timepiece, with an original focus on the needs of maritime navigation. In Switzerland, timepieces certified by the Contrôle Officiel Suisse des Chronomètres (COSC) may be marked as Certified Chronometer or Officially Certified Chronometer. Outside Switzerland, equivalent bodies, such as the Japan Chronometer Inspection Institute, have in the past certified timepieces to similar standards, although use of the term has not always been strictly controlled.
Explores the design and scaling of electromagnetic actuators for optimal energy extraction and power output, including considerations for thermal limitations and manufacturing constraints.
At room temperature, mechanical motion driven by the quantum backaction of light has been observed only in pioneering experiments in which an optical restoring force controls the oscillator stiffness1,2. For solid-state mechanical resonators in which oscil ...
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The present invention concerns a pivot comprising two assemblies, namely a central assembly (401) and a peripheral assembly (400). These two assemblies are mobile in rotation relative to each other around an axis of rotation (A). The pivot is characterized ...
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The recent adoption of silicon components by the mechanical watch industry has triggered the search for new time bases to advantageously replace the traditional balance and hairspring oscillator. In particular, flexure-based oscillators manufactured in sil ...