Hairspring is the core of the operation of mechanical timepieces. Before the hairspring was invented, mechanical clocks rely on the pendulum as an oscillator to achieve energy division and travel time. In the 17th century, the hairspring invented by Huygens significantly reduced the size of the clock. Today, the hairspring we often talk about refers to the balance spring (Balance Spring or Hair Spring) on the balance wheel, although the spring (Barrel Spring) is also a type of spring (Spring). The appearance of the hairspring is the basis for the emergence of pocket watches and wristwatches and the end of the glorious era of pendulum clocks.
Pocket watch balance spring
The hairspring follows the physical law of the swing period. In clocks, the frequency of the hairspring balance system is related to the moment of inertia of the balance spring. As a precision mechanical structure, the material, effective length, thickness, and width of the hairspring are essential to the entire system. influences. Because of this, when mechanical clocks continue to develop today, hairsprings are still the highest threshold for measuring the technological strength of various watch factories, and there are very few watch factories in the world that can independently develop and produce hairsprings.
From the early iron-based alloy hairspring materials, to later INVAR iron alloy hairsprings doped with nickel, to today’s mainstream Nivarox hairsprings, for hundreds of years, the hairspring materials have continued to evolve with the development of material science, and the watch industry has also continued to explore More perfect hairspring material. What makes it perfect? As a clock often needs to run for years or even decades without interruption, the number of oscillations of the hairspring reaches a very alarming number. ), So only a handful of metal alloys can be used to make hairsprings. In addition, the hairspring must be able to resist the influence of some external environments in daily life. The early effects mainly came from temperature differences. After that, antimagnetic became more and more important. Invar alloy invented by Charles Edouard Guillaume, Nobel Prize winner at the beginning of the 20th century. It solves this problem and has a certain antimagnetic property.
German Moritz Grossmann watch uses Nivarox 1 hairspring
In 1931, Nivarox hairspring, a nickel-chromium steel alloy developed by Dr. Straumann, came out. It consists of seven elements. This weakly magnetic metal alloy has good oxidation and deformation resistance, anti-fracture, automatic compensation, no corrosion, and has good Thermal deformation coefficient, that is, it has good resistance to temperature difference. Because of this, Nivarox is widely used in the watch industry and has replaced the INVAR alloy hairspring as the mainstream in the market. Today, in the entire watchmaking industry, Nivarox has become the first choice for non-produced balance spring factories, and has become an ace in the hands of the Swatch Group. Over 95% of Swiss watch brands and some non-Swiss brands are using Nivarox FAR. Gossamer. As mentioned earlier, the hairspring is a product with technical barriers. A watch factory with the strength of self-made hairsprings is generally not a foreign supplier, so Nivarox has become the overlord in the field of general hairsprings. Although in addition to Nivarox, there are still other hairspring manufacturers such as Altokapa, Japan’s Seiko, Citizen, etc., but the reason why Nivarox dominates the hairspring industry is its high cost performance.
NOMOS Homemade Blue Steel Gossamer
Of course, Nivarox FAR produces other hairsprings in addition to Nivarox hairsprings of different specifications, such as the Elinvar nickel-chromium constant elastic steel hairspring used by Richard Mill, Anachron hairspring better than Nivarox, and special hairsprings customized for other companies. Wait.
In recent years, silicon hairsprings have been popularized in fine watchmaking, and the Swatch Group has begun to try to enter the low-end market. This is a new exploration of hairspring materials in modern watchmaking. From metal alloys to non-metallic materials, it is likely to be a metamorphosis. Regardless of who invented the silicon hairspring, for the moment, from top brands Patek Philippe, Breguet, Athens, etc., to our familiar Omega, and the people such as Mido, all have launched silicon-based hairsprings.
Patek Philippe Spiromax
Patek Philippe’s cutting-edge research project is based on silicon and plays the trilogy of silicon escapements, including the Pulsomax escapement fork, the Silinvar escape wheel and the Spiromax spring. Rolex released the Syloxi hairspring based on silicon material in 2014 for 2236 automatic movement. It is worth noting that this is a female watch movement. Rolex successfully developed an excellent silicon hairspring, but it has not been popularized. The watch is precisely because silicon material has its inherent defects, Rolex believes that it is still not the most satisfactory hairspring material. Brands such as Athens, Omega, Breguet, Jacques Droe, Blancpain, etc. use silicon hairsprings relatively frequently. Silicon hairsprings have a huge advantage over metal hairsprings. They are completely unaffected by magnetic fields, but the biggest drawback is that they are too brittle.
Rolex Syloxi hairspring
In the past few years, discussions about silicon hairsprings are very frequent. The advantage is that the performance is better than metal alloy hairsprings. The disadvantage is that damage can only be replaced, which is not conducive to long-term development. If this watch is still 30 years later, but the corresponding parts may not be able to match at this time, it is impossible to repair, and it is even difficult to match a suitable metal hairspring. However, from the perspective of the market as a whole, most of the watches only exist in the present, and can really stay that long, after all, there are still a few, so the advantages may outweigh the disadvantages in general.
Mido Silicone Caliber 80 Belem
Mido this year launched the Belem Celli series of 80-hour power reserve watches, using silicon hairspring, this should be the first silicon-spring watch in the current affordable price. This means that the silicon hairspring will no longer be high, and it will likely become popular later. Just as the Swatch Group pressed its competitiveness on the 80-hour long power movement, it once again expanded its absolute advantage in the low-end market. .
When it comes to autonomous hairsprings, who do we most easily think of? I will first think of Rolex’s Parachrom paramagnetic blue niobium hairspring. According to official information, it is stronger than ordinary hairsprings in terms of shock resistance, antimagnetic and so on. It is also the current mainspring of Rolex. Parachrom hairspring plays an important role in the accurate movement of Rolex, the excellent performance in actual use, and the long life of the watch.
Rolex Parachrom hairspring
Seiko and the Materials Science Laboratory of Tohoku University have developed the Spron elastic material for the mainspring and hairspring of Seiko watches. Spron has a variety of specifications, of which the mainspring is mainly used for the Spron 510, Spron 530 (high frequency movement), etc., while the spring is used for Spron 610, and so on. Spron is a nickel-cobalt alloy with five characteristics of high strength, super elasticity, corrosion resistance, magnetic resistance and temperature difference resistance. It is widely used in Seiko and some Japanese watches.
In addition, there are some brands that are developing their own hairspring materials, and there are also some lesser-known hairspring materials such as Richard Mille’s AK 3 hairspring.
Winding hairspring on end
The difference of the hairspring material essentially lays down the performance of the hairspring, but still requires some additional processing to make the performance of the hairspring better. Most of the time, the hairspring we see is flat, with a winding curve on the end. Generally speaking, this type of end winding is a Breguet-type end winding (or Phillips end curve). The appearance of this curve is because the end of the hairspring is fixed on the hairspring pile, which affects the concentricity of the hairspring expansion and consequently affects the travel time. Therefore, this part of the end is ‘truncated’ by the way of the curve to reduce this effect.
The end of the hairspring is thickened and the inner triangle frame
Breguet Double Hairspring
Montblanc column hairspring
Jaeger-LeCoultre domed hairspring
In addition, there are many types of hairsprings. Here are a few examples, and then I have time to explain them one by one.