The Impact Protection – the Parachute of the Mechanical Clockwork

Function And Construction Of Shock Protection For Mechanical Watches

A little imprudence – and all life is already rests: a shock, a blow or even a fall can be fatal for a mechanical clockwork – if it is not protected by a so-called shock protection. Today the most common are made by the Swiss companies Incabloc and KIF Parechoc.

There is a name in the history of watchmaking, which is legendary. No one else meets as often as he does: Abraham Louis Breguet. No one is as imaginative as he is, has made a lasting change in watchmaking and has brought so many new innovations to this day. One of the numerous inventions of the master also includes a shock protection for the balance of a mechanical movement. These pins, to which the balance of the balance rest on either side, are particularly thin. This makes sense: the thinner the pin, the less friction is generated between the pin and the bearing. In relation to this, however, the balance is relatively heavy, so that here is a particularly vulnerable and vulnerable weak point of the clock.

The Shock Protection Of Mechanical Watches Goes Back To Abraham Louis Breguet

An unfortunate shock, an impact of the mechanical clock is sufficient, and the balance of the balance can already break. In 1790 Breguet introduced a first solution to the problem. At first, the watchmaker according to the invention shortens the pins and gives them a trumpet-like shape, which is why trumpets are also called trumpet taps. Finally, Breguet decides to attach a small capstone to a spring blade so that the balance can move in the axial direction during impact. After this stress, the capstone returns to its original position and the watch continues to run without damage, reported by Itypetravel. Breguet also has the right name for this elastic balance suspension: He calls it “parachute”, to German parachute. Today, the French name for an impact protection is “parechoc”. Breguet’s simple and yet so great invention is the forerunner of the shock absorbers that are customary today. After all, different manufacturers and designers follow the great master and develop impact protection on the basis of their invention. However, only a few of them are generally accepted: the most common impact systems for mechanical movements today are two Swiss companies, KIF Parechoc SA in Le Sentier and Incabloc SA in La Chaux-de-Fonds.

The products of these two manufacturers protect the balancing shafts according to the same principle: the holes and capstones in which the pin of the balancing shaft rotates are resiliently mounted. This means that a spring presses the loose capstone into a bearing shell. The result: the thinnip, which is relatively thin in order to reduce the friction, transmits the energy of the movement to its bearing and can deviate laterally and vertically in case of strong impacts. The function of the spring holding the bearing blocks goes beyond this protection even further. Due to its returning force, it ensures that the pins of the balance shaft are correctly positioned again after a shock. According to KIF Parechoc SA, KIF Parechoc SA also has good shock absorption and the right centering of the balance axle after a shock. The good hold of an oil drop on the capstone, a slight opening of the spring without the whole shock absorber has to be removed, as well as an adequate Size of the complete system.

It is only sufficient to protect the balance of the balance; the shafts of the work wheels are more robust and are rarely damaged even in the case of strong impacts. They therefore rotate in rigid bearings. But back to the protagonists of the shock protection: Incabloc and KIF Parechoc. The former company is based on the shock absorbers developed for the balance shafts in the 1920s and 1930s. To date, this system has been improved by Incabloc in details, the production is also becoming more and more efficient and automated in different steps – but the principle of shock protection has not changed.

The Incabloc Shock Absorber Has A Lyre-Shaped Spring

The characteristic feature of the Incabloc shock absorber is a lyre or lyre-shaped spring, which keeps the bearing and capstone in position and touches at two points. This spring can be opened to allow removal of the hole and cover stone for cleaning and oiling.

These are only a few parts of an ingenious whole: Common shock protection systems consist of five parts each for the upper and lower balance pins. The base is an annular support made of hard brass, which is inserted into the balance block or the circuit board and holds the other parts. Its inner bore comprises two conical surfaces corresponding to the conical outer surfaces of the chuck. Into this chuck is pressed an oiled, fixed hole stone, in which the pin rotates.

The internal bore of the support and the external profile of the perforated stone chuck (chuck) ensure the self-centering of the peg. Above all, there is an unbored capstone, which is flat and outward on the side of the balance pin. This capstone is held in place by the pressure of a flat spring. The spring is clamped in the upper part of the support and is made of nickel-plated or gilded special steel.

Its exact composition is guarded at Incabloc as a treasure. On request it is said that the material of the Lyrafeder is secret. There, the block and the balance pins are made by means of modern turning machines made of brass by means of a lathe, the so-called Décolletage. The lyre feathers are punched out. The bearing and deck stones are purchased as required. The assembly takes place partly by hand, partly by hand.

KIF Parechoc Manufactures Shock Absorbers With Metal Springs

At KIF Parechoc, the production is carried out according to a similar principle. Headquartered in Le Sentier, France, the company specializes in shock-proofing with metal springs for luxury watches, for example, it works almost entirely for the entire noble neighborhood in the Vallée de Joux. After all, one can refer to over 60 years of experience: KIF Parechoc has been producing shock protection systems since 1944; also backfunctions are part of the company’s offer. These two systems have been combined in an extremely innovative manner: the company offers a set in which the device is connected to a permanently mounted shock absorber.

With the exception of the synthetic rubies, that is, of the watch-watches that KIF Parechoc purchases from Swiss suppliers, all parts of the KIF impact protection system are manufactured and finished in-house. The brass parts are manufactured in the modern turning shop and are nickel-plated or gilded depending on the product and the customer’s request. The springs – usually made of steel – are also produced in-house. They are punched and then subjected to thermal treatment for hardening and nickel plating or gilding. The production of chuck and shock protection support always requires the highest precision. Tolerances in the range of 0.003 millimeters must be observed. This also applies to manufacturers of purchased watches: they must work according to the exact specifications of KIF Parechoc and must also comply with strict tolerances.

No less complicated than the production of the individual parts is their assembly to the complete shock protection. At KIF Parechoc, the assembly is carried out in specially trained workshops either manually or semi-automatically – depending on the type of impact protection and the required quantity. The company even produces small numbers of special systems according to customer requirements. So that even unusual mechanical clockwork is protected from shocks and shocks.