Movement (clockwork)
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Mechanical clockwork movement
Assembly comprising all the main parts of a watch, also used in building many forms of apparatus such as mechanical or electrical counters, switching-devices, bells and, in general, all small portable appliances whose functions are dependent on the division of time. The essential parts are:
- The (watch)motor: formed of the mainspring coiled inside the barrel, the ratchet-wheel and the transmission-wheel
- The movement/train: consisting of wheels riveted to their pinions: centre-wheel, third wheel, fourth wheel. The train transmits the driving-power to:
- The escapement: a mechanism that maintains the oscillations of the regulating organ, consisting of an balance wheel and the pallet fork.
- regulating organ: the balance with its spring is fixed to the staff. This device is a mechanical oscillator. It receives from the escapement the impulses required to make it run for 24 hours, with a safety-margin of normally 10-12 hours. (By so-called 8-Day movements, for at least 192 hours).
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Mechanical Watch movement
The above mechanism is completed by the following parts:
- Winding-mechanism: mechanism that winds the mainspring
- Setting-mechanism: usually connected to the winding-mechanism by common parts for altering the position of the hands of a watch. Originally, the hands had to be pushed directly by hand to set the watch to the right time; later, a key was used to shift them.
And by the Indicating Organs:
- (watch)Dial: indicating "face" of the watch, a plate of metal or other material, bearing various markings to show at least the hours, minutes and seconds. Dials vary very much in shape, decoration & material. The indications are given by means of numerals, divisions or symbols of various types, printed, raised, applied and / or combined with other skills like "cloisonné" enamel, diamond-set or "pavé" decoration.
- (watch)Hands: Indicator, usually made of a thin, light piece of metal, very variable in form, which moves over a graduated dial or scale. Usually for each indication of time one specific hand is needed. The earliest watches had only an hour hand. The English horologist Daniel Quare is believed to have introduced the minute hand about 1691, though it did not come into general use until the early 18th Century. The earliest hands were strong and heavy, there still being no glass to protect the dial. In the late 18th Century, they became more slender and more elegant; they were made by hand, with the file and graver and the holes were cut out in the turns with a bow and ferrule. About 1764, they were first cut out of a strip of metal by means of a punch and hammer. Later on, about 1830, they were stamped out in the fly-press. They were often adorned with precious stones. In watches of the finest quality, the Breguet hand, then the Louis XV and Louis XVI hands, were made of delicately chased gold. Modern hands are turned out in a great variety of styles, qualities and colours. High-grade hands are made of solid gold or tempered steel and have a polished pipe or head. Brass is otherwise generally used for makings hand, protected & decorated either by a thin galvanized layer of gold or rhodium or some kind of lacquer. There are many various types and shapes of hands adapted to the use as well as to the required aesthetic of the watch, e.g. for perfect readability Webb C. Ball prescribed strong heavy hands in his standards for Railroad chronometers, without prescribing the looks.
- Motion work (U.S.A.: dial-train): a train fitted under the dial, for transmitting the rotation of the minute-pinion to the hour hand
And finally
- The bottom plate and bars support all the above mentioned parts.
Watch movements come in various shapes, i.e. round, tonneau, rectangular, rectangular with cut corners, oval & baguette and sizes, and are measured in "lignes", respectively lately in millimeters. Each specific watch movement is called a caliber. Basically, the movement parts are separated into two main categories: those belonging to the ébauches and those belonging to the assortments.
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Antique Mechanical Watch movement
The artisans of the time were using
- pillar-plates
- fusée and verge escapement.
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Clock movement
- clockwork-movement with a motor in the form of a spring or a weight. The oscillator is usually a pendulum. Small mechanical or electrical wall- and table-clocks are made with an oscillator in the form of a sprung balance, as used in a watch.
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