timekeeping

timekeeping department

timekeeping departments

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timekeeping department

timekeeping department

timekeeping report

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n. exact timing

1 timing.

2 timekeeping, timing.

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► nombre masculino

1 timing

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SM timekeeping, timing

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masculino timekeeping

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masculino timekeeping

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timekeeping

cronometraje manual/electrónico manual/electronic timekeeping

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cronometraje nm

timekeeping

f

1. chronometry

2. SPORT timekeeping

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chronometry; timing

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f timekeeping

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Zeitmessung f

1. chronometry

2. SPORT timekeeping

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chronometry n.

f SPORT timekeeping

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f -, -n (SPORT)

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Zeitnahme f SPORT timekeeping

SUBJECT AREA: Horology

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When Breguet was 11 years old his father died and his mother married a Swiss watchmaker who had Paris connections. His stepfather introduced him to horology and this led to an apprenticeship in Paris, during which he also attended evening classes in mathematics at the Collège Mazarin. In 1775 he married and set up a workshop in Paris, initially in collaboration with Xavier Gide. There he established a reputation among the aristocracy for elegant and innovative timepieces which included a perpétuelle, or self-winding watch, which he developed from the ideas of Perrelet. He also enjoyed the patronage of Marie Antoinette and Louis XVI. During the French Revolution his life was in danger and in 1793 he fled to Neuchâtel. The two years he spent there comprised what was intellectually one of his most productive periods and provided many of the ideas that he was able to exploit after he had returned to Paris in 1795. By the time of his death he had become the most prestigious watchmaker in Europe: he supplied timepieces to Napoleon and, after the fall of the Empire, to Louis XVIII, as well as to most of the crowned heads of Europe.

Breguet divided his contributions to horology into three categories: improvements in appearance and functionality; improvements in durability; and improvements in timekeeping. His pendule sympathique was in the first category and consisted of a clock which during the night set a watch to time, regulated it and wound it. His parachute, a spring-loaded bearing, made a significant contribution to the durability of a watch by preventing damage to its movement if it was dropped. Among the many improvements that Breguet made to timekeeping, two important ones were the introduction of the overcoil balance spring and the tourbillon. By bending the outside end of the balance spring over the top of the coils Breguet was able to make the oscillations of the balance isochronous, thus achieving for the flat spring what Arnold had already accomplished for the cylindrical balance spring. The timekeeping of a balance is also dependent on its position, and the tourbillon was an attempt to average-out positional errors by placing the balance wheel and the escapement in a cage that rotated once every minute. This principle was revived in a simplified form in the karussel at the end of the nineteenth century.

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SUBJECT AREA: Electronics and information technology, Horology

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After serving an apprenticeship with a clock-maker in Blaubeuren, Hipp worked for various clockmakers before setting up his own workshop in Reutlingen in 1840. In 1842 he made his first electric clock with an ingenious toggle mechanism for switching the current, although he claimed that the idea had occurred to him eight years earlier. The switching mechanism was the Achilles' heel of early electric clocks. It was usually operated by the pendulum and it presented the designer with a dilemma: if the switch made a firm contact it adversely affected the timekeeping, but if the contact was lightened it sometimes failed to operate due to dirt or corrosion on the contacts. The Hipp toggle switch overcame this problem by operating only when the amplitude of the pendulum dropped below a certain value. As this occurred infrequently, the contact pressure could be increased to provide reliable switching without adversely affecting the timekeeping. It is an indication of the effectiveness of the Hipp toggle that it was used in clocks for over one hundred years and was adopted by many other makers in addition to Hipp and his successor Favag. It was generally preferred for its reliability rather than its precision, although a regulator made in 1881 for the observatory at Neuchâtel performed creditably. This regulator was enclosed in an airtight case at low pressure, eliminating errors due to changes in barometric pressure. This practice later became standard for observatory regulators such as those of Riefler and Shortt. The ability of the Hipp toggle to provide more power when the clock was subjected to an increased load made it particularly suitable for use in turret clocks, whose hands were exposed to the vagaries of the weather. Hipp also improved the operation of slave dials, which were advanced periodically by an electrical impulse from a master clock. If the electrical contacts "chattered" and produced several impulses instead of a single sharp impulse, the slave dials would not indicate the correct time. Hipp solved this problem by producing master clocks which delivered impulses that alternated in polarity, and slave dials which only advanced when the polarity was changed in this way. Polarized impulses delivered every minute became the standard practice for slave dials used on the European continent. Hipp also improved Wheatstone's chronoscope, an instrument that was used for measuring very short intervals of time (such as those involved in ballistics).

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отсчет времени
хронометраж
[Департамент лингвистических услуг Оргкомитета «Сочи 2014». Глоссарий терминов]

EN

timing
Another term for timekeeping.
[Департамент лингвистических услуг Оргкомитета «Сочи 2014». Глоссарий терминов]

Тематики

• спорт (общая терминология)

Синонимы

• хронометраж

EN

• timekeeping
• timing

f

1. timekeeping

2. LING. adverbial expression of time

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f (GRAM)

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Zeitbestimmung f

1. timekeeping

2. LING adverbial expression of time

roe.

huevas de bacalao cod roe

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► nombre femenino

1 roe, spawn

\

huevas de esturión caviar sing

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1) (tb: huevas) (Culin) roe; (Zool) eggs, spawn sing

2) pl huevas Chile *** (=testículos) balls ***

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1) tb

2) (Andes vulg) ( testículo)

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= spat.

Ex. This type of pearl culture using the spats produced in the hatchery is the first in its kind in India.

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* hueva de ostra = oyster spat.

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1) tb

2) (Andes vulg) ( testículo)

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tb huevas ( Coc) roe;

( Zool) spawn

( Andes vulg) (testículo): huevas balls ( vulg), bollocks ( vulg)

como las huevas ( Chi vulg); shitty ( vulg)

estar hasta las huevas ( Andes vulg): me tiene hasta las huevas con lo de la puntualidad I'm up to here with him going on about timekeeping ( colloq), I'm pissed off with him going on about timekeeping ( vulg)

ni hueva ( Chi vulg); damn all ( colloq)

C ( Méx fam) ‹flojera› laziness

debería estudiar pero me da hueva I ought to study but I can't be bothered

echar la hueva to bum around (sl)

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◊ huevas (Coc) roe;

◊ huevas balls (vulg), bollocks (BrE vulg)

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hueva nf

1. [de pescado] roe;

huevas de bacalao cod roe

2. Méx Fam [aburrimiento]

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hueva nf

: roe, spawn

SUBJECT AREA: Horology

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Al-Jazari entered the service of the Artuqid Kings of Diyar Bakir c.1180. In 1206 the then King, Nasir al-Din, instructed him to write a book describing the things he had constructed, among which were six water clocks. The timekeeping mechanism of these clocks was not innovative and was derived from earlier Hellenistic examples. Unlike Chinese and Hellenistic water clocks, al-Jazari's clocks had no astronomical indications and were intended to display the time, in temporal or unequal hours, both audibly and visually in an arresting and entertaining manner. The timekeeping was controlled by the flow of water from a vessel which contained a float to operate the clock mechanism. An ingenious device was used to ensure that the flow of water was constant during the day and could be set to a different constant flow during the night, to allow for the variation in the length of the temporal hours. Al-Jazari's clocks have not survived, but models have been constructed from the description and illustrations in the manuscripts.

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SUBJECT AREA: Horology, Metallurgy

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Guillaume came from a family of clock-and watchmakers. He was educated at the Gymnasium in Neuchâtel and at Zurich Polytechnic, from which he received his doctorate in 1883 for a thesis on electrolytic capacitors. In the same year he joined the International Bureau of Weights and Measures at Sèvres in France, where he was to spend the rest of his working life. He retired as Director in 1936. At the bureau he was involved in distributing the national standards of the metre to countries subscribing to the General Conference on Weights and Measures that had been held in 1889. This made him aware of the crucial effect of thermal expansion on the lengths of the standards and he was prompted to look for alternative materials that would be less costly than the platinum alloys which had been used. While studying nickel steels he made the surprising discovery that the thermal expansion of certain alloy compositions was less than that of the constituent metals. This led to the development of a steel containing about 36 per cent nickel that had a very low thermal coefficient of expansion. This alloy was subsequently named "invar", an abbreviation of invariable. It was well known that changes in temperature affected the timekeeping of clocks by altering the length of the pendulum, and various attempts had been made to overcome this defect, most notably the mercury-compensated pendulum of Graham and the gridiron pendulum of Harrison. However, an invar pendulum offered a simpler and more effective method of temperature compensation and was used almost exclusively for pendulum clocks of the highest precision.

Changes in temperature can also affect the timekeeping of watches and chronometers, but this is due mainly to changes in the elasticity or stiffness of the balance spring rather than to changes in the size of the balance itself. To compensate for this effect Guillaume developed another more complex nickel alloy, "elinvar" (elasticity invariable), whose elasticity remained almost constant with changes in temperature. This had two practical consequences: the construction of watches could be simplified (by using monometallic balances) and more accurate chronometers could be made.

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See also: Le Roy, Pierre

SUBJECT AREA: Horology

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Huygens was born into a cultured and privileged class. His father, Constantijn, was a poet and statesman who had wide interests. Constantijn exerted a strong influence on his son, who was educated at home until he reached the age of 16. Christiaan studied law and mathematics at Ley den University from 1645 to 1647, and continued his studies at the Collegium Arausiacum in Breda until 1649. He then lived at The Hague, where he had the means to devote his time entirely to study. In 1666 he became a Member of the Académie des Sciences in Paris and settled there until his return to The Hague in 1681. He also had a close relationship with the Royal Society and visited London on three occasions, meeting Newton on his last visit in 1689. Huygens had a wide range of interests and made significant contributions in mathematics, astronomy, optics and mechanics. He also made technical advances in optical instruments and horology.

Despite the efforts of Burgi there had been no significant improvement in the performance of ordinary clocks and watches from their inception to Huygens's time, as they were controlled by foliots or balances which had no natural period of oscillation. The pendulum appeared to offer a means of improvement as it had a natural period of oscillation that was almost independent of amplitude. Galileo Galilei had already pioneered the use of a freely suspended pendulum for timing events, but it was by no means obvious how it could be kept swinging and used to control a clock. Towards the end of his life Galileo described such a. mechanism to his son Vincenzio, who constructed a model after his father's death, although it was not completed when he himself died in 1642. This model appears to have been copied in Italy, but it had little influence on horology, partly because of the circumstances in which it was produced and possibly also because it differed radically from clocks of that period. The crucial event occurred on Christmas Day 1656 when Huygens, quite independently, succeeded in adapting an existing spring-driven table clock so that it was not only controlled by a pendulum but also kept it swinging. In the following year he was granted a privilege or patent for this clock, and several were made by the clockmaker Salomon Coster of The Hague. The use of the pendulum produced a dramatic improvement in timekeeping, reducing the daily error from minutes to seconds, but Huygens was aware that the pendulum was not truly isochronous. This error was magnified by the use of the existing verge escapement, which made the pendulum swing through a large arc. He overcame this defect very elegantly by fitting cheeks at the pendulum suspension point, progressively reducing the effective length of the pendulum as the amplitude increased. Initially the cheeks were shaped empirically, but he was later able to show that they should have a cycloidal shape. The cheeks were not adopted universally because they introduced other defects, and the problem was eventually solved more prosaically by way of new escapements which reduced the swing of the pendulum. Huygens's clocks had another innovatory feature: maintaining power, which kept the clock going while it was being wound.

Pendulums could not be used for portable timepieces, which continued to use balances despite their deficiencies. Robert Hooke was probably the first to apply a spring to the balance, but his efforts were not successful. From his work on the pendulum Huygens was well aware of the conditions necessary for isochronism in a vibrating system, and in January 1675, with a flash of inspiration, he realized that this could be achieved by controlling the oscillations of the balance with a spiral spring, an arrangement that is still used in mechanical watches. The first model was made for Huygens in Paris by the clockmaker Isaac Thuret, who attempted to appropriate the invention and patent it himself. Huygens had for many years been trying unsuccessfully to adapt the pendulum clock for use at sea (in order to determine longitude), and he hoped that a balance-spring timekeeper might be better suited for this purpose. However, he was disillusioned as its timekeeping proved to be much more susceptible to changes in temperature than that of the pendulum clock.

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SUBJECT AREA: Horology

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Riefler's father was a scientific-instrument maker and clockmaker who in 1841 had founded the firm of Clemens Riefler to make mathematical instruments. After graduating in engineering from the University of Munich Sigmund worked as a surveyor, but when his father died in 1876 he and his brothers ran the family firm. Sigmund was responsible for technical development and in this capacity he designed a new system of drawing-instruments which established the reputation of the firm. He also worked to improve the performance of the precision clock, and in 1889 he was granted a patent for a new form of escapement. This escapement succeeded in reducing the interference of the clock mechanism with the free swinging of the pendulum by impulsing the pendulum through its suspension strip. It proved to be the greatest advance in precision timekeeping since the introduction of the dead-beat escapement about two hundred years earlier. When the firm of Clemens Riefler began to produce clocks with this escapement in 1890, they replaced clocks with Graham's dead-beat escapement as the standard regulator for use in observatories and other applications where the highest precision was required. In 1901 a movement was fitted with electrical rewind and was encapsulated in an airtight case, at low pressure, so that the timekeeping was not affected by changes in barometric pressure. This became the standard practice for precision clocks. Although the accuracy of the Riefler clock was later surpassed by the Shortt free-pendulum clock and the quartz clock, it remained in production until 1965, by which time over six hundred instruments had been made.

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See also: Marrison, Warren Alvin