The St.Petersburg Centre of Watch & Clock Restoration

“Shock resistance” - what does it mean?

Do you know this term – “anti-strike watch”? Of course, you know. This is a kind of watch that is not sensitive to drops and strokes. In any case it remains intact and keeps its accuracy movement as before. Are you sure? How can a watch stand against a stroke? Should a watch owner who likes an extreme life style to carry out experiments, testing its reliability? Konstantin Chaykin, a famous watchmaker from St.-Petersburg, can give you some tips concerning this problem.

Is it worth punching a table
when you have a watch on your hand?

It is absolutely clear that there is no such brand of watch that can stand against any stroke. A powerful blow against a fine mechanism consisting of multitude fragile components can turn into an expensive repair. However, almost all modern watches are protected rather well against some shaking and strokes. It is interesting that a quartz watch is less sensitive to the factors that can break a clockwork. For example, if you punch a table in a burst of anger then a balance axle of mechanic watch on your hand can bend or break. Quartz watches do not have any complicated mechanic units so almost all of them are resistant to not very strong shaking and strokes.

Actively promoted ‘anti-strike function’ of mechanic watches means a special protective device, so-called ‘shock-absorber’, that softens a possible shock. The shock-absorber prevents any damage or deformation of a balance pivot, the most sensitive part of clockwork that is mainly responsible for the reliability and accuracy movement. A developed system of this anti-strike mechanism guarantees prevention from some damage. Today it is being applied by all serious manufacturers producing watches.

Principle of a shock-absorber operation:

If a stroke is directed along axis a balance pivot A presses a superimposed stone B and as a result a stone goes upward. Under this condition spring B bends and gives the stone back to the starting position. A pivot continues to go up till a thickened part of a balance pivot G sets against a stopper.

If a stroke is directed from aside a balance pivot A presses a stone located in a moveable support D, shifting aside till its thickened part sets against the stopper. The thickened parts of a balance pivot accept the main stroke pressure and protect fine pivots from any damage or bend.

Some historic facts
about watch inventions

In 1789 a famous watch-maker Abraham-Lois Breguet invented the first anti-strike device which got the name “parachute” (French “parachute” from Greek para - ‘against’ and French ‘chute’- ‘falling down’).

As a legend goes once Breguet dropped his pocket watch deliberately in front of some witnesses who were watching the scene in terror. After that the craftsman, as if nothing had happened, picked the watch up and calmed everybody down showing them his latest invention – the watch device for protection of a balance axle.

Thus Breguet’s construction gained everybody’s appreciation and admiration. But in that time not only an anti-strike mechanism, but the watch as well (only pocket ones then) was quite expensive and the manufacturing process was very complicated. That is why Breguet’s shock-absorber was not widely used in practice.

Only 140 years later, when the watch (already wrist watch at that time as well) became quite widely spread and available, the idea of anti-strike device was revived.

There appeared various types of shock-absorbers in Switzerland, such as Parechok or Shockresist. However, system Incabloc patented in 1933 has become the most popular.

Do you want to make a durability test?

As a rule anti-strike watch is tested (as a product) on a special stand, which imitates a stroke after a fall from one meter height on a wooden platform. The results of a test are considered positive, if a watch works and the accuracy movement changes only to a certain extent and no faults affecting the watch operation (any damage of additional devices or its mechanism exterior) can be traced.

Nevertheless, the ordinary usage of watch does not include any pressure from load impact. The lasting effect of such pressure can break down the work of the balance unit, which hinders the accuracy movement. Therefore I would not recommend you to throw your favorite watch at the floor and against walls in public, startling people. It is worth bothering about maintaining not only mechanism. It does not matter if a watch a mechanic or quartz one it can break down after a stroke, get scratched, or watch crystal can slip out. Watch-hands can fly off as well as the other design elements of the watch dial, the winder and so on.

"…Do not use your watch in the way which is not allowed by the manufacturer. Keep the watch from being affected by damaging factors, which can lead to its breakdown. The watch, bearing some traces of mechanic damage due to not proper handling, cannot go under a repair with warranty…" When you have been warned you are well-armed, as they say.
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Kseniya Beketova
«Kotoruy Chas?», No 11/2004

The St.Petersburg Watch&Clock Atelier
The Centre of Watch&Clock Restoration
off. 36, Malodetskoselskiy pr.
St.Petersburg, 190013, Russia
phones: +7 (812) 703-17-56
+7 (812) 316-56-39
+7 (812) 911-02-71
mail@clockmaker.ru