The Incabloc shock protection system is the trade name for a spring-loaded mounting system for the

jewel bearing A jewel bearing is a plain bearing in which a metal spindle turns in a jewel-lined pivot hole. The hole is typically shaped like a torus and is slightly larger than the shaft diameter. The jewels are typically made from the mineral corundum ...

s that support the

balance wheel A balance wheel, or balance, is the timekeeping device used in mechanical watches and small clocks, analogous to the pendulum in a pendulum clock. It is a weighted wheel that rotates back and forth, being returned toward its center position by a ...

in a mechanical

watch A watch is a portable timepiece intended to be carried or worn by a person. It is designed to keep a consistent movement despite the motions caused by the person's activities. A wristwatch is designed to be worn around the wrist, attached by ...

, to protect the wheel's delicate pivots from damage in the event of physical

shock Shock may refer to: Common uses Collective noun *Shock, a historic commercial term for a group of 60, see English numerals#Special names * Stook, or shock of grain, stacked sheaves Healthcare * Shock (circulatory), circulatory medical emerge ...

, such as if the watch is dropped.

History

The Incabloc system was invented in 1934 by Swiss engineers Georges Braunschweig and Fritz Marti, at Universal Escapements, Ltd, of La Chaux-de-Fonds, Switzerland. It is manufactured by Incabloc, S.A.Incabloc, S.A.
website Similar systems are

ETA Eta (uppercase , lowercase ; grc, ἦτα ''ē̂ta'' or ell, ήτα ''ita'' ) is the seventh letter of the Greek alphabet, representing the close front unrounded vowel . Originally denoting the voiceless glottal fricative in most dialects, ...

's Etachoc, Kif,

Seiko , commonly known as Seiko ( , ), is a Japanese maker of watches, clocks, electronic devices, semiconductors, jewelry, and optical products. Founded in 1881 by Kintarō Hattori in Tokyo, Seiko introduced one of the first quartz watches and the ...

's Diashock, and

Citizen Citizenship is a "relationship between an individual and a state to which the individual owes allegiance and in turn is entitled to its protection". Each state determines the conditions under which it will recognize persons as its citizens, and ...

's Parashock. The pivots and jewel bearings that support a watch balance wheel are fragile in comparison to the mass they must support, and without shock protection are the part of the watch most likely to be damaged under impact. Before the widespread use of shock protection devices like Incabloc, broken balance staffs were a common type of damage requiring watch repair. The Incabloc system uses a "

lyre The lyre () is a stringed musical instrument that is classified by Hornbostel–Sachs as a member of the lute-family of instruments. In organology, a lyre is considered a yoke lute, since it is a lute in which the strings are attached to a yoke ...

-shaped" spring to allow the delicate bearings to shift in their settings under impact, until a stronger shoulder of the staff contacts the strong metal endpiece, so that the pivots and bearings don't have to bear the force of the impact. When the impact is over, the springs guide the parts back to their original positions. The staff itself does not move relative to the jewel bearing, but the whole bearing is carried in a metal bushing that is free to move in the metal endpiece, under the control of the spring. Some modern balance wheels use a simpler arrangement, where, taking advantage of the low cost of modern synthetic rubies, a large jewel moves as its own mobile bushing.

References

External links

{{wikibooks, Budget Watch Collecting/Shock Protection
Official siteIncabloc FAQMaterial used for Incabloc spring
Watches

History

See also

References

External links