Stührling Original Fine Luxury Timepieces

ANTIMAGNETIC

Said of a watch whose movement is not influenced by electromagnetic fields that could cause two or more windings of the balancespring to stick to each other, consequently accelerating the rate of the watch. This effect is obtained by adopting metal alloys (e.g Nivarox) resisting magnetization. Mechanical movements are easily influenced by the magnetic fields often found in common everyday places. This problem is generally solved by the use of anti- or nonmagnetic components in the movement.

BALANCE SPRING
Component of the regulating organ, determines the movement's precision. The material used is mostly a steel alloy (e.g. Nivarox), an extremely stable metal compound, In order to prevent the system's center of gravity from continous shifts, hence differences in rate due to the watch's position, some modifications were adopted. These modifications included Breguet's overcoil (closing the terminal part of the spring partly on itself, so as to assure an almost perfect centering) and Philips curve (helping to eliminate the lateral pressure of the balance-staff pivots against their bearings). Today, thanks to the quality of materials, it is possible to assure an excellent precision of movement working even with a flat spring.

COMPLICATION
Additional function with respect to the manual-winding basic movement for the display of hours, minutes and seconds. Today, certain feautures, such as automatic winding or date, are taken for granted, although they should be defined as complications are moonphase, power reserve, GMT and full calendar. Further functions are performed by the so-called great complications, such as split-second chronograph, perpetual calendar, tourbilon device, and minute repeater.

CROWN

The crown is used to wind and set a watch. A few simple turns of the crown will get an automatic movement started, while a manually wound watch is completely wound by the crown. Usually positioned on the case middle and allows winding, hand setting and often date or GMT hand setting. As it is linked to the movement through the winding stem passing through a hole in the case. For waterproofing purposes, simple gaskets are used in water-resistant watches, while diving watches adopt screwing systems (screw-down crowns).

GONG
Harmonic flattened bell in a steel alloy, generally positioned along the circumference of the movement and struck by hammers to indicate time by sounds. Size and thickness determine the resulting note and tone. In watches provided with minute-repeaters, there are often two gongs and the hammers strike one note to indicate hours, both notes together to indicate quarters and the other note for the remaining minutes. In more complex models, euipped also with en-passant sonerie devices, there may be up to four gongs producing different notes and playing even simple melodies (such as the chime of London's Big Ben).

GUILLOCHE

A surface decoration usually applied to the dial and the rotor using a grooving tool with a sharp tip, such as a rose engine, to cut an even pattern onto a level surface. The exact adjustment of the tool for each new path is controlled by a device similiar to a pantograph, and the movement of the tool can be controlled either manually or mechanically. Real guillochis (the correct term used by a master of guilloche) are very intricate and expensive to produce, which is why most dials decorated into this fashion are produced by stamping machines.

JEWEL

Precious stone used in movements as a bearing surface. Generally speaking, the steel pivots of wheels in movements turn inside synthetic jewels (mostly rubies) lubricted with a drop of oil. The jewel's hardness reduces wesr to a minimum even over long periods of time (50 to 100 years). The quality of watches is determined mainly by the shape and finishing of jewels rather than by their number (the most refined jewels have rounded holes and walls to greatly reduce the contact between pivot and stone).

MOONPHASE

A function available in many watches, usually combined with calendar-related features.A disc beneath an aperture on a dial which rotates in synchronization with the phases of the moon.The moonphase disc advances one tooth every 24 hours. Normally, this wheel has 59 teeth and assures an almost perfect synchronization with the lunation period, i.e. 29.53 days (in fact, the disc shows the moonphases twice during a single revolution). However, the difference of 0.03 days, i.e. 44 minutes each month, implies the need for a manual adjustment every two and a half years to recover one day lost with respect to the real state of moonphase. In some rare case, the transmission ratio between the gears controlling the moonphase are calculated with extreme accuracy so as to require manual correction only once in 100 years.

POWER RESERVE
The amount of time a hand-wound or automatic watch can run without having to be re-wound or worn. 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 wondow). The related mechanism is made up of a series of gears linking the winding barrel and hand. Recently, specific modules wre introduced which may be combined with the msot popular movements.

PULSIMETER CHRONOGRAPH

A scale onn the dial, flange, or bezel that, in conjunction with the second hand, may be used to measure a pulse rate. A pulsometer is always marked with a reference number ---- if it is marked with gradue pour 15 pulsations, for example, then the wearer counts fifteen pulse beats. At the last beat, the second hand will show what the pulse rate is in beats per minute on the pulsometer scale.The pulsimeter scale shows, at a glance, the number of pulse beats per miunte. The observer releases the chrongraph 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.

REGULATING UNIT
Made up by balance spring, governing the division of time within the mechanical movement, assuring its regular running and abburacy. As the balance works like a pendulum, the balance sprin's function consists of its elastic return and starting of a new oscillation. This combined action determines the frequency, i.e. the number of vibrations per hour, and affects the rotation speed of the different wheels. In fact the balance, by its oscilliations, at every vibration (through the action of the pallets), frees a tooth of the escape wheel ( Escapement). From this, motion is transmitted to the fourth wheel, which makes a revolution in one minute, to the third and then the center wheel, the latter making a full rotation in one hour. However, everything is determined by the correct time interval of the oscillations of the balance.

REGULATOR
A timepiece sufficiently accurate to be used as a benchmark from which to test others. Regulates the functioning of a movement by lengthening and shortening the active section of the balance spring. It is positioned on the balance-bridge and encompasses the balance spring with its two pins near its fixing point on the bridge itself. By shifting the index, the pins also are moved and, by consequence, the portion of the balance spring capable of bringing the baalance back is lengthened or shortened by synchronozing with it, and is thus ready for another recording. Pressure on the split pusher releases the split-second hand, which instantly joins the chronograph hand if the split-second hand happens to be blocked.

TACHOMETER or TACHYMETER

A scale on the dial, flange, or bezel of a chronograph that, in conjunction with the second hand, gives the speed of a moving object. The tachometer scale is calibrated to show the speed of a moving object, such as a vehicle, over a known distance. The standard length on which the calibration is based is always shown on the dial, e.g. 1,000, 200 or 100 meters, or ---- in somes cases ---- one mile. As the moving vehicle, for instance, passes the starting-point of the measured course whose length corresponds to that used as the basis of calibration, the observer releases the chrongraph hand and stops it as the vehicle passes the finishing point. The figure indicated by the hand on the tachometer scale represents the speed in kilometers or miles per hour.

TELEMETER
By means of the telemeter scale, it is possible to measure the distance of a phenomenon that is both visible and audible. The chronograph hand is released at the instant the phenomenon is seen; it is stopped when the sound is heard, and its position on the scale shows, at a glance, the distance in kilometers or miles separating the phenomenon from the observer. Calibration is based upon the speed at which sound travels through the air, approximately 340 meters or 1,115 feet per second. During a thunderstorm, the time that has elapsed between the flash of the lightning and the sound of the thunder is registered on the chronograph scale.

TOURBILLON PRINCIPLE

The purpose of the tourbillon is to compensate for the effects of gravity on a mechanical watch. When it is in a vertical position, a mechanical watch’s regulating organ – the balance, balance spring and escapement – undergoes imperceptible errors of rate with each oscillation, due to the effects of gravity. By housing the regulating mechanism in a cage rotating on its own axis, generally once a minute, a variety of vertical positions results, which compensate for each other, producing a very constant average rate and extreme running precision.

Though as good as moot in a wristwatch, this superb horological highlight is seen as a sign of technological know-how in the modern era. Its manufacture, one of the most complex and delicate, necessitates a perfect mastery of watchmaking and its techniques. Although this device is not absolutely necessary for accuracy purposes today, it is still appreciated as a complication of high-quality watches.

WINDING, AUTOMATIC VIBRATION
Movement of the pendulum or other oscillating bodies, limited by two consecutive extreme positions. In an alternate (pendulum or balance) movement, a vibration is a half of an oscillation. The number of hourly vibrations corresponds to the frequency of a watch movement, determined by the mass and diameter of a balance and the elastic force of the balance spring. The number of vibrations per hour (vph) determines the breaking up of time ( the "steps" of a second hand). For instance, 18,000 vph equals a vibration duration of 1/5 second; in the same way 21,600 vph = 1/6 second; 28,800 vph = 1/8 second; 36,000 vph = 1/10 second. Until the 1950s, wristwatches worked mostly at a frequency of 18,000 vph; later, higher frequencies were adopted to produce a lower percentage of irregularities to the rate. Today, the most common frequency adopted is 28,800 vph, which assures a good precision standard and less lubrication problems than extremely high frequencies, such as 36,000 vph.