pendulum clock

pendulum clock

• pendulum clock

• pendulum clock

pendulum clock

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заводи́ть часы́ — wind (up) a clock

часы́ отстаю́т — a timepiece loses

подводи́ть часы́ вперё́д или наза́д — set the watch forward or backward

часы́ с 8-дне́вным заво́дом — 8-day windup clock

часы́ торо́пятся [ухо́дят вперё́д] — the timepiece gains

установи́ть часы́ по, напр. моско́вскому вре́мени — set ones watch according to, e. g., Moscow time

антимагни́тные часы́ — nonmagnetic watch

астрономи́ческие часы́ — astronomical clock

а́томные часы́ — atomic clock

га́зовые часы́ — wet-gas meter

доро́жные часы́ — travel clock

звё́здные часы́ — sidereal clock

индика́торные часы́ — dial indicator

камерто́нные часы́ — tuning fork clock

ква́рцевые часы́ — quartz-crystal [crystal-controlled] clock

ма́ятниковые часы́ — (free) pendulum clock

молекуля́рные часы́ — molecular clock

нару́чные часы́ — wristwatch

песо́чные часы́ — sand glass

процеду́рные часы́ — medical clock

радиомая́чные часы́ — time-signal radio [time-signal broadcasting] station

со́лнечные часы́ — sun-clock, sundial

судовы́е часы́ — ships clock

часы́ с цифровы́м отсчё́том — digital clock

та́бельные часы́ — portal time clock

ша́хматные часы́ — chess-clock

щитовы́е часы́ — instrument-panel [switchboard] clock

электри́ческие часы́ — electric clock

электро́нные часы́ — electronic clock

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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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Shortt entered the Engineering Department of the London and South Western Railway as an engineering cadet in 1902, remaining with the company and its successors until he retired in 1946. He became interested in precision horology in 1908, when he designed an instrument for recording the speed of trains; this led to a long and fruitful collaboration with Frank HopeJones, the proprietor of the Synchronome Company. This association culminated in the installation of a free-pendulum clock, with an accuracy of the order of one second per year, at Edinburgh Observatory in 1921. The clock's performance was far better than that of existing clocks, such as the Riefler, and a slightly modified version was produced commercially by the Synchronome Company. These clocks provided the time standard at Greenwich and many other observatories and scientific institutions across the world until they were supplanted by the quartz clock.

The period of a pendulum is constant if it swings freely with a constant amplitude in a vacuum. However, this ideal state cannot be achieved in a clock because the pendulum must be impulsed to maintain its amplitude and the swings have to be counted to indicate time. The free-pendulum clock is an attempt to approach this ideal as closely as possible. In 1898 R.J. Rudd used a slave clock, synchronized with a free pendulum, to time the impulses delivered to the free pendulum. This clock was not successful, but it provided the inspiration for Shortt's clock, which operates on the same principle. The Shortt clock used a standard Synchronome electric clock as the slave, and its pendulum was kept in step with the free pendulum by means of the "hit and miss" synchronizer that Shortt had patented in 1921. This allowed the pendulum to swing freely (in a vacuum), apart from the fraction of a second in which it received an impulse each half-minute.

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See also: Marrison, Warren Alvin

f pendulum clock

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f pendulum clock

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Pendeluhr f pendulum clock

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pendulum clock n.

1 clock.

(carrera) contra reloj (sport) time trial

hacer algo contra reloj to do something against the clock

funcionar como un reloj (figurative) to go like clockwork

es un reloj (informal) you can set your watch by him (es puntual)

reloj analógico analog watch

reloj de arena hourglass

reloj biológico body clock, biological clock

reloj de bolsillo pocket watch

reloj de cuco cuckoo clock

reloj despertador alarm clock

reloj digital digital watch

reloj interno (computing) internal clock

reloj de pared grandfather clock

reloj de pulsera watch, wristwatch

reloj de sol sun dial

2 watch, ticker.

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► nombre masculino

1 clock (de pulsera) watch

\

como un reloj figurado like clockwork

contra reloj against the clock

reloj de arena hourglass

reloj de caja / reloj de péndulo grandfather clock

reloj de cuco cuckoo clock

reloj de pared clock

reloj de pulsera wristwatch

reloj de sol sundial

reloj despertador (de mesita) alarm clock 2 (de pulsera) alarm watch

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1) clock

2) watch

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[re'lo]

- como un reloj

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masculino (de pared, mesa) clock; (de pulsera, bolsillo) watch

- reloj checador

- reloj de arena

- reloj de cuco or cucú

- reloj de pie

- reloj de pulsera

- reloj de sol

- reloj despertador/registrador

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= clock, watch, timepiece.

Ex. 'Good grief!', he cried, catching sight of the clock.

Ex. She looked at her watch; it was 9:25.

Ex. Even now, hundreds of years after his death, his timepieces stand proud in historic buildings around the world.

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* andar como un reloj = fit as a fiddle.

* aparcamiento controlado por reloj = metered parking.

* bolsillo para el reloj = watch pocket.

* cadena de reloj = fob.

* carrera contra reloj = race against time, race against the clock.

* como un reloj = as regular as clockwork, like clockwork.

* controlado por reloj = metered.

* cuadrante del reloj = clock face.

* dar cuerda a un reloj = wind + clock.

* en el sentido de las agujas del reloj = clockwise.

* en sentido contrario a las agujas del reloj = counterclockwise, anti-clockwise.

* esfera del reloj = clock face.

* faltriquera de reloj = watch pocket.

* hora de reloj = clock hour.

* ir a contra reloj = race against + time, race against + the clock.

* ir en contra del reloj = race against + time, race against + the clock.

* reloj automático = timer.

* reloj biológico = body clock, biological clock.

* reloj cucú = cuckoo clock.

* reloj de arena = sand timer, hourglass, sandglass.

* reloj de bolsillo = fob watch.

* reloj de cuco = cuckoo clock.

* reloj de cucú = cuckoo clock.

* reloj de muñeca = wristwatch [wrist watch].

* reloj de péndulo = pendulum clock.

* reloj de pulsera = wristwatch [wrist watch].

* reloj despertador = alarm clock.

* reloj interno = body clock, biological clock.

* reloj que registra el tiempo de conexión = accounting clock.

* volver el reloj atrás = turn + the clock back.

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masculino (de pared, mesa) clock; (de pulsera, bolsillo) watch

- reloj checador

- reloj de arena

- reloj de cuco or cucú

- reloj de pie

- reloj de pulsera

- reloj de sol

- reloj despertador/registrador

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(de pared, mesa) clock; (de pulsera, bolsillo) watch

dar cuerda a un reloj to wind (up) a clock/watch

mi reloj (se) adelanta/atrasa my clock/watch gains/loses

este reloj se ha parado this clock has stopped

funciona or marcha como un reloj it's going like clockwork

contra reloj against the clock

ser un reloj to be as regular as clockwork

body clock

( Méx) time clock

hourglass

pocket watch

chiming clock

quartz clock/watch

cuckoo clock

grandfather clock

wristwatch

sundial

alarm clock

digital clock/watch

time clock

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◊ funciona como un reloj it's going like clockwork;

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reloj nm

hacer algo contra reloj to do sth against the clock;

funcionar como un reloj to go like clockwork;

es un reloj [es puntual] you can set your watch by him

reloj analógico analogue watch;

reloj de arena hourglass;

reloj atómico atomic clock;

reloj biológico body clock, biological clock;

reloj de bolsillo pocket watch;

reloj checador time clock;

reloj de cuarzo quartz clock;

reloj de cuco o Am cucú cuckoo clock;

reloj de cuerda wind-up watch;

reloj despertador alarm clock;

reloj digital digital watch;

reloj de pared grandfather clock;

reloj de péndulo pendulum clock;

reloj de pulsera, RP reloj pulsera, Col, Méx reloj de pulso watch, wristwatch;

reloj de sol sundial

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m clock; de pulsera watch, wristwatch;

reloj para fichar time clock;

ser un reloj fam be as regular as clockwork fam ;

ir o

marchar como un reloj go o run like clockwork;

contra reloj against the clock;

carrera contra reloj DEP race against the clock

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reloj nm

1) : clock

2) : watch

reloj de arena : hourglass

reloj de pulsera : wristwatch

como un reloj : like clockwork

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reloj n

1. (de pulsera) watch [pl. watches]

2. (de pared) clock

m pendulum

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pendolo¹ s.m.

1 (fis.) pendulum*: pendolo semplice, composto, simple, compound pendulum; pendolo a compensazione, compensation pendulum; pendolo balistico, ballistic pendulum; moto del pendolo, pendulum motion; oscillazione del pendolo, swing of the pendulum // (astr.) pendolo sismico, pendulum seismograph

2 (edil.) ( archipendolo) plumb-rule

3 ( orologio a pendolo) pendulum-clock.

pendolo², pendulo agg.

1 (letter.) hanging; pendulous, pendent

2 (anat.) velo pendolo, uvula palatina.

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sostantivo maschile

1) fis. pendulum

2) (orologio)

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pendolo

/'pεndolo/

sostantivo m.

 1 fis. pendulum

 2 (orologio) orologio a pendolo grandfather clock.

hanging, hanging-down.

pendulum.

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► nombre masculino

1 pendulum

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SM pendulum

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masculino pendulum

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= pendulum.

Ex. The article has the title 'The pendulum swings to the right: censorship in the eighties'.

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* reloj de péndulo = pendulum clock.

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masculino pendulum

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pendulum

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péndulo nm

pendulum

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m pendulum

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péndulo nm

: pendulum