Watch glossary: N, O, P, Q.
Trade name (from the producer's name) of a steel alloy, resisting magnetization, used for modern self-compensating balance springs. The quality level of this material is indicated by the numeral following the name in decreasing value from 1 to 5.
An observatory-tested precision watch that obtained the relevant rating chronometer certificate.
Complete oscillation or rotation movement of the balance, formed by two vibrations.
Device of the escapement transmitting part of the motive force to the balance, in order to maintain the amplitude of oscillations unchanged by freeing a tooth of the escape wheel at one time.
PERPETUAL CALENDAR see calendar, perpetual
PILLAR-PLATE or MAIN PLATE
Supporting element of bridges and other parts of a movement.
Combines with a wheel and an arbor to form a gear. A pinion has less teeth than a wheel and transmits motive force to a wheel. Pinion teeth (normally 6 to 14) are highly polished to reduce friction to a minimum.
End of an arbor turning on a jewel support. As their shape and size can influence friction, the pivots of the balance-staff are particularly thin and, hence, fragile, so they are protected by a shockproof system.
Metal, treated by a galvanizing procedure in order to apply a slight layer of gold or another precious metal (silver, chromium, rhodium or palladium) on a brass or steel base.
A synthetic resin used for watch crystal.
POINçON DE GENEVE
Distinction assigned by the Canton of Geneva to movements produced by watchmaker firms of the Region and complying with all the standards of high horology with respect to craftsmanship, small-scale production, working quality, accurate assembly and setting. The Geneva Seal is engraved on at least one bridge and shows the Canton's symbol, i.e. a two-field shield with an eagle and a key respectively in each field.
Brilliant metal surface obtained on the watch case with fine abrasive. Compare to brushed finish.
Duration (in hours) of the residual functioning autonomy of a movement after it has reached the winding peak. The duration value is displayed by an instantaneous indicator: analog (hand on a sector) or digital (through a window). The related mechanism is made up of a series of gears linking the winding barrel and hand. Recently, specific modules were introduced which may be combined with the most popular movements.
Accuracy rate of a watch, a term difficult to define exactly. Usually, a precision watch is a chronometer whose accuracy-standard is certified by an official watch-rating bureau.
The pulsimeter scale shows, at a glance, the number of pulse beats per minute. The observer releases the chronograph hand when starting to count the beats and stops at the 30th, the 20th or the 15th beat according to the basis of calibration indicated on the dial.
PUSHER, PUSH-PIECE or PUSH-BUTTON
Mechanical element mounted on a case for the control of specific functions. Generally, pushers are used in chronographs, but also with other functions.
Abbreviation of Physical Vapor Deposition, a plating process consisting of the physical transfer of substance by bombardment of electrons.
The quartz movement uses the famously stable vibration frequency of a quartz crystal subjected to electronic tension (usually 32,868 Hz) as its norm. The fact that a quartz-controlled second hand jumps to the tact of each second is a concession to the use of outside energy. This technical revolution found its way to the world's wrists in the late 1960s. This was a principally Swiss invention - the first working quartz wristwatches were manufactured by Girard-Perregaux and Piaget as the result of an early joint venture within the Swiss watch industry, but the Japanese (primarily Seiko) came to dominate the market with new technology.
A movement powered by a quartz crystal. Quartz crystals are very accurate. They can be mass produced which makes them less expensive than most mechanical movements which require a higher degree craftsmanship.
on Jan 11, 2010 | Watches