====== Shock protection ======
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The **shock protection** (or **shock absorber**) is an important part of any modern mechanical watch [[movement]]. The most common shock protection today is //[[Incabloc]]//, another well-known is //[[Kif]] Flector//.

==== The task ====
Elastically mounted [[jewel]] bearings of the [[balance staff]] ensure that their [[pivot]]s don't break at hard pushes, e.g. when the watch falls down.

==== Explanation of the operation ====
The capstone **a** is under pressure of the spring **b**. For a vertical impact this [[jewel]] can lift as far as the stop **c** abuts a fixed part. To damp lateral shocks the jewel is mounted in a chuck that is provided with an inclined surface **d**, which allows a slight shift; this is limited by the shaft stopper **e**, which abuts against a fixed part of the frame.

===== History =====
The first shock protection devices integrated into a watch movement appeared in the early 19th century. [[Breguet, Abraham-Louis|Abraham-Louis Breguet]] is known to have created a device called the "pare-chute" which protected the pivots of the balance from shock. It used a cone-shaped cup for the pivot which was itself mounted in a bearing on a spring. This allowed it to shift in the event of a shock but then to re-center itself after. Breguet famously demonstrated this invention by dropping his watch in front of bystanders and picking it up to show that it was still working.

Although so-called "pare-choc" anti-shock devices were widely seen in the late 19th and early 20th century, it is the [[1933]] invention of [[Incabloc]] by [[Marti, Frédéric|Frédéric "Fritz" Marti]] that brought these to the masses. Marti's company, [[Portescap]], developed a shock proofing mechanism that could easily be adapted to any existing watch movement. These were pioneered by [[Election]], Marti's former employer, until its [[1931]] bankruptcy. After this, Marti and [[Braunschweig, Georges|Georges Braunschweig]] founded "[[Portescap|La Porte-Echappement Universel SA]]" across the street from the Election factory in [[La Chaux-de-Fonds]] and began producing his innovative devices. The term "incassable" ("unbreakable") was widely used on these durable watches, so Incabloc and many other technologies included "inca" in their name.

Other companies also developed shock protection in the 1930s. [[Wyler]]'s [[Incaflex]] [[balance]], patented in [[1927]], had flexible arms unlike anything else on offer. [[Helvetia]] (from [[General Watch Co.]] offered mass-produced pare-choc watches by [[1930]] and [[Reconvilier Watch Co.]] offered pare-choc on [[Roskopf]] movements in [[1932]]. Even Marti's own patent, which passed to the Neuchâtel bank after [[Election]] was liquidated, was offered to other companies before being sold to [[Doxa]] in [[1933]] and then to [[Zodiac]] in [[1935]]. But these were integrated with specific movements and were not generally available to other manufacturers.

Portescap's success with Incabloc as a universal shock protection quickly brought competitors. [[Grenier Erismann-Schniz]] introduced [[Shock-Resist]] by [[1935]], which used a spiral-shaped spring. Another competitor after [[1952]] was [[Emo|Emo SA]]. [[Morf, Ernest|Ernest Morf]], former director of [[Wyler]], produced [[Vibrax]], which used a straight leaf spring and a long flexible shaft. But it was [[Parechoc]] of [[Le Sentier]] that would become Portescap's true competitor for Incabloc. Under the brand name [[Kif]], Parechoc would be the primary alternative.

By the 1950s, anti-shock devices were a strong selling point for watches. The Kif or Incabloc logo became a key differentiator, even as over 50 different shock protection devices were available by the 1960s. But by the 1970s such devices were commonplace, with [[Seiko]] and [[Citizen]] designing their own [[Diashoc]] and [[Parashoc]].

Today every watch includes shock protection similar in concept to Incabloc or Kif. [[Nivarox FAR]] produces [[Nivachoc]], which is claimed to be more precise in resetting the proper positioning of the balance staff after a shock. This is used on many [[ETA]] movements, including those for [[Breguet]] and [[Omega]]. And Rolex, which had long relied on Kif anti-shock, created its own [[Paraflex]] system in [[2005]].

===== Weblinks =====
  *[[http://www.incabloc.ch/incabloc_en.html|Incabloc]] (official site)
  *[[http://great-british-watch.co.uk/watch-anti-shock-settings/|Watch Anti-Shock Settings]]


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