Shock-absorbing device

A shock-absorbing device is the sprung setting that holds the two jewel bearings of the balance staff. Under impact the setting is free to move and then returns to position, so the thin balance pivots are not the part that takes the blow. The Swiss industry has standardised the vocabulary for these parts: the Federation of the Swiss Watch Industry's list of available NIHS norms includes NIHSG 42-01, "Amortisseurs de chocs – Chatons combinés – Terminologie" (dated 1963/2022), together with three further NIHSG 42 norms on shock absorbers and companion norms on combined settings.

The test such a device exists to pass is ISO 1413:2016, Horology — Shock-resistant wrist watches, edition 3, published April 2016 and listed by ISO as Published; it superseded ISO 1413:1984, which ISO lists as Withdrawn. ISO's catalogue abstract states that the standard "specifies the minimum requirements for shock-resistant wrist watches and describes the corresponding test method" and that "It is based on the simulation of the shock received by a wrist watch while falling from a height of 1 m onto a horizontal wooden floor (an equivalent surface is described in B.1.1)." The same document is carried in Switzerland as NIHS 91-10 (SN ISO 1413). This Codex's entry on shock-resistance covers the standard itself, and its requirements are not restated here.

"Incabloc" is a registered trademark of Incabloc SA for one family of these devices, a trade name, not a generic word for the class. The company's own description names a "pierced jewel", an "endstone", a "bushing", a "Lyre-spring®" and a block, and states that the space between the pierced jewel and the endstone "forms an 'oil sump' of optimised shape and size". Those are the manufacturer's statements about its own product; the page carries no reference to ISO 1413, and its promotional wording is not repeated here as fact.