Watches do not make much noise - besides the ticking and the winding of a rotor. Therefore, it is more fascinating, if the mechanical construction does not only feature optical signs, but also acoustical ones. Eterna's first alarm watch was introduced in 1912 and was originally designed as a travel watch. In 1974 AS (Adolf Schild) launched an automatic alarm movement, the calibre 5008, where the rotor also winds up the additional barrel of the alarm movement. This movement is still used in the alarm watches of NIVREL.
The balance cock balance refers to the upper part of the construction in which the balance wheel is mounted.
The barrel is a drum-shaped housing which is needed for housing the spring and is usually closed by a lid. The barrel rotates freely on a shaft and carries the mainspring on its inside.
A bezel is one of the basic components of a watch case and serves mostly to attach the watch glass. It is either rigidly connected to the clock or rotatable (e.g. bezels of dive watches).
The size of the date is not characteristic of the name "Big Date", but rather the construction. The two numbers of the date are shown by two separate interdigitated plates.
Especially luxury watches have often been equipped blued screws and hands since the 16th Century. It primarily serves as oxidation protection, but has also become a special decoration for high class watches. The parts of a watch being blued are heated on a specific metal plate, until the desired color is reached. Depending on the light incidence, a change of color from light blue to black is possible.
A special type of design for hands, a very elegant shape with a hole at the tip. The design is named after the famous inventor and watchmaker Abraham-Louis Breguet.
Simple mechanism to lock a bracelet or leather strap.
The chronograph is a complication that features a stop function. The title complication is really true in terms of a chronograph, because its construction is almost as complicated as a perpetual calendar (see below). NIVREL Chronographs contain the well-known ETA Calibre Valjoux 7750 or. 7751, which realizes the chronograph mechanism by using a cam control.
Clous de Paris
'Clous de Paris' is the name of a special kind of guilloche dial. The guilloche pattern id created with small square knobs. Sometimes they are referred to as 'roof tiles'.
Additional functions of watch movements that go beyond the indication of hours, minutes, and seconds, are called 'complications' in the watch industry. Examples are a chronograph function, a full calendar, a moon phase display or an alarm function.
The so-called 'Finissage' is the last working step when building a watch, including the final finishing and fine machining by the so-called Finisseur (worker who takes the last step).
Flyback Chronograph (Retour en Vol)
The chronograph hand jumps to reset and immediately starts again by pressing a button during the timing process of a chronograph. Without the flyback function three steps are necessary for this process (stop, jump to reset, start).
The so-called Full Calendar offers a complete set of calendar functions on the dial by displaying week day, date, and month. In all months with less than 31 days, a manual correction of the date and month indication is required.
Geneva Stripes (Côtes de Genève)
The term Geneva stripes is a watch industry-specific term that refers to a special, rib-like decoration on surfaces of watch movement parts, such as flywheels (rotors) and bridges.
By using a gong for the indication of the time can be played acoustically in a repeater watch. Since about 1800 it replaced the previously used percussion bells. Gongs are metal rods which are spirally curved. The gong is struck by the hammer mechanism in order to make the indication signal.
On 15 October 1582 a new calendar reform by Pope Gregory XIII. Came into effect in Rome. It is still valid today and removed the tiny residual error of the Julian calendar introduced in 45 BC. In spite of the leap year a time shift of 12 minutes occurs every year. To bring the calendar into alignment with the seasons, the year 1582 was reduced by 10 days. In addition, only those should remain leap years in which the full centuries are divisible through 400 (e.g. 1600, 2000).
Guilloche is a style of engraving fine and mostly artistic designs and patterns into watch cases or dials.
The caliber Landeron 248 is a special hand-wound movement and chronograph. The chronograph function is implemented using a cam controller and has a 60-second counter and varying a 30 - or 45-minute counter. The movement has a power reserve of 43 hours.
Identifies genuine alligator leather which is used for high quality wristbands for watches. These watch straps are carefully selected, often handmade, and add tothe necessary elegance of a luxury timepiece.
Is a type of silicate glass. The watch industry speaks of mineral crystal to make a better distinction with the softer and lighter plastic glass or by the harder sapphire crystal. A mineral crystal is normally a flat glass either on top or bottom of the watch case . The glass is of the sam type as used e.g. in normal windows. Untreated it has a hardness of about 400 Vickers and is thus approximately 20 times harder than plastic.
A moon phase complication shows the different stages of the moon within one month. A moon phase indication is realized by using a plate with two opposite moons on a gear with 59 cogs, which moves forward every day. Thus, one moon phase takes 29.5 days. In fact, the moon takes 44 minutes and 2.9 seconds longer. After 2 1/2 years the deviation counts up to one day and the watch has to be adjusted.
One Year Calendar
In addition to the time, the one year calendar of NIVREL shows the date and the month. The one year calendar is able to differentiate the various lengths of the months. The watch has to be adjusted just once a year, on the 28th or 29th of February.
A perpetual calendar (like a full calendar) indicates date, day, month and often the moon phase. Furthermore, it 'knows' the lengths of the months and inserts a 29th of February in every leap year. A small hand indicates the time to the next leap year. Technically, the programming of the four different lengths of month is a considerable challenge.
The power reserve is the maximum duration of a mechanical movement after it is fully wound. Originally, the power reserve was developed to remind a pocket watch owner to wind up the movement. Behind the hand indicator on the dial, a differential gear is responsible for the notification of the remaining spring tension.
PVD coating is a working process in which various materials such as steel, alloy or silver are subjected to a vapor deposition. There is an exchange of the so-called ion particles from the source material of the clock by 'different colored' ions in this process.
The chronograph with drag indicator (Rattrapante) enables the measuring of an interim time. A second hand, which runs under the stop second hand, is activated by pressing a button.
In general, the repeater function of a watch is a sound mechanism and is one of the most complicated watches of all. The additional capability is not visible but audible. A push-button activates the bell of the watch. Originally, repeaters were developed in a time, in which electric light had not been invented. The repeater was the watch that could be used in the dark as well!
The repeater mechanism of a watch repeats the current time by an acoustic signal when a push button or slider is launched.
Rhodinized (Rhodium plated)
Rhodium plating is a chemical or electrolytic coating of metals. The metal is thus protected and given a radiant glow. In addition, the rhodium plating causes a higher surface hardness.
A rotor or flywheel is a rotating part of the watch movement that helps winding the watch. It is connected with the barrel via a transmission, and thus clutches the spring.
The hardest glass that is used for durable, high quality watches is the so-called sapphire crystal. The special advantage is that sapphire crystals are resistant against solvents. Also, it is almost impossible to scratch them.
A screwed balance is a special version of the balance wheel in a mechanical watch movement. The balance wheel itself receives additional screws that are used to balance the the mass and therefore the moment of inertia of the watch.
Superluminova is a luminous material used for numerals and hands. Superluminova glows in the dark after it was charged in normal daylight.
Swans-neck fine adjustment
A type of regulation. An additional part is used that is shaped like a swan’s neck and allows a fine adjustment of a watch movement.
The term sweep second refers to a second hand that is located in the center of the watch dial. If a watch has a sweep second the shaft of the minute wheel will be pierced to make way for the shaft of the second hand.
A tachymeter scale on a dial or bezel of a watch is a specific indication that can be used to measure speed with a chronograph watch. More precisely, the tachymeter scale together with the stop second indication can be used to compute a speed based on travel time or to measure a distance based on speed.
200 years ago Abraham-Louis Breguet invented this complication to adjust the negative influence of the gravitation on the movement. He put the balance in a cage, which turned around once in one minute. The tourbillon, which is difficult to construct, is still seen as a sign of highest watchmaking artistry.