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viernes, 14 de enero de 2011

History of the Chronograph Watch

Source

The Greek words "chronos" and "graph" stand for "time" and "writing". A chronograph is a chronometric (time-measuring) device which contains a mechanism that allows to stop at least one hand to facilitate reading of the elapsed time.

The chronograph was invented by a Frenchman, named Rieussec, back in 1821. Literally, this was the only timepiece that bore the name Chronograph rightly. It was actually written on the dial with a small pen attached to the index. The length of the arc of the circle displayed the time that had passed. The index was fixed, while the dial turned. In 1822, Rieussec was granted a patent for his invention.

Around 1910, the chronograph, also refered to as stopwatch, was introduced as a wrist watch. Soon it was a very sought after type of watch, only to gain in popularity through the years. When the Swatch watch company started the production of affordable and fashionable chrono's in early 1990, they sold like hot cakes, as were the later versions. Nowadays, almost every respectable watch company has a chonograph in its collection.

The Real Chronograph 

Chronographs are watches that can meassure time in different ways. Besides normal timekeeping, they can be used for one or more specific time measurements. For this, the dial has several sub dials with a scale, from which the measurements can be read. A central second hand can be started and stopped, without interfering with the continuous time.

The design of the dial of chronographs depends on the number of subsidiary dials. This can be two, three or even four. One of them is likely to be situated on the "9" of the dial, and shows the continuous seconds. When the chronograph is activated by pushing the top button, the central seconds hands starts moving. After one complete cycle is completed and the hand has returned to "12", the minute-indicator, located at the "3", will jump one position. With this simple type of chronograph a period of 30 or 45 minutes can be measured.

More complicated chrono's have a subregister for total hours, often located at 6 o'clock on the dial. This enable to take measurements up to 12 hours. Even fairly simple chronographs have a very complicated movement.

Technical Innovations: 


The developpement of the chronograph folllowed the technical innovation of the wrist watch very closely. When in the 1930's manufacturers started producing waterproof watches, this know how was used in the production of chronographs shortly after.

In 1933, the firm Universal introduced the first waterproof chronograph to the public under the name "Colonial". And shortly after developpers managed to protect the movement of a watch against magnetical influences, the first anti-magnetic chronograph followed.

The Sporting Image:

At the beginning of this century, stopwatches were used mainly by sportsmen and the military. Professionally, they had to be able to measure the time of certain events accurately. For them, a chronograph was a practical choice.

The difference between Gold and Silver is very often a matter of hundredths of a second. Mechanical watches can't measure this, so quartz chonographs are used.

To racing ehthusiasts, a stopwatch with tachometer is very useful. For example, to measure the speed of a formula 1 race car, the time to cover a distance of 1000 meters is measured, and the tachometer scale automatically indicates the speed in kilometers per hour.

Divers have their own time piece as well. Basic requirement is that the case is waterproof. That is why a diver's chronograph has round pushers, a screw on crown, and a screw back case which is provided with rubber gasket-rings to keep water out. At a depth of 30 meters there is hardly any daylight penetrating, so luminescent numereals and hands on a dark dial are necessary.

The most important feature of any diver's watch is the diving ring. This is a rotating bezel around the dial or the crystal. It is divided in minutes and often has a triangular fluorescent marking at 12. Before divers take to the water, they have calculated the time they can spend under water.

For Fashion:


Today, wearing a chronograph is a matter of taste, rather than professional. The chronograph is becoming a fashion statement. Practical applications are still plentyful, of coarse, like the boiling of "the perfect egg", which requires very accurate timing. the biggest appeal of the chrono is probably the exciting and sportive image, for it is the watch for astronauts, racing car drivers and pilots. Professions that are known to be adventurous.

Beside those who choose functionality or image, there is a small group of enthusiasts (collectors) that considers the movement to be the most beautiful part of the watch. If you have ever seen a chronograph opened up, you might know what this is about.

As a rule, a chronograph is more expensive than a normal or automatic watch, due to the complexity and craftmenship necessary for manufacturing.

Drs. Pjèr Strolenberg Copyright © 1996 Robert Keulen http://www.xs4all.nl/~rkeulen/watch/chronos.html

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