balance spring


Swan-neck Regulator
A high-end regulator pin: Swan-neck regulator. Swan neck, a collet fixing the end of the hairspring, can produce aesthetic effect. Patek Philippe, Vacheron Constantin and Chopard has applied swan-neck regulator to their in-house mechanical movements. Swan-neck regulator has three effects. First, it can stick the regulator clip tightly. Second, it can ensure accuracy be adjusted to a satisfying and accurate range. Third, it embodies the heritage of decoration and the culture of watchmaking, and it is also a symbol of the advanced watch. Besides, snail-shaped regulator has been applied to the pocket watch.

Technology Innovation on Swan-neck Regulator
To control vibration period of balance wheel by adjusting the length of hairspring is simple and effective. Swan-neck regulator does well in solving displacement of balance spring holder. Under violent vibration, the malposition of hairspring controlled by regulator clip and hairspring stud will cause the deflection. The puzzle has been overcome. Swan-neck regulator was applied for a patent in Munich, Germany and numbered “EP2290477”.

2. Free Sprung Balance
Free Sprung balance has better stability and isochronism than regulator pin.If I have to look for a flaw, the collocation of free sprung balance and Breguet spring will make the balance wheel higher above 1 millimetre. Free Sprung regulating tool is to adjust vibration period by adjusting wheel weight.It mainly includes Rolex Microstella and Patek Philippe Gyromax.

Patek Philippe Gyromax
When it come to Free-sprung, U-shaped Gyromax weights in gold from Patek Philippe occurs to me. The Gyromax regulating tool has been used for more than 60 years. To rotate the gap toward the central axis of the balance can make the watch go slow. The number of weights is eight generally, and there’re 4 and 6 weights. PP Calibre CH 28-520 has silicon balance wheel with 4 weights in gold. Don’t look down these weights, they can affect amplitude to 180 degrees, practical, reliable, beautiful. On August 18, 1948, Patek Philippe applied for two patents: CH280067 and CH261431. CH280067 is on how U-shaped weights were assembled on the balance. At that time, weights were set in the flutes so that it can reduce air friction. The setting is similar to Chopard’s flyer”variner”. With the progress of technology, the difficulty of processing and manufacturing has been reduced. CH261431 is on the specification design for U-shaped weights.

Rolex Microstella
In fact, Rolex Microstella has a longer history than Patek Philippe Gyromax. During the World War Ⅱ,Rolex applied for a patent No.CHX2239668 which was invented by AEGLER HANS HERMANN, an early partner of Rolex. Rolex ordered movements from him at that time. The edge of the balance wheel was assembled with lead screws and nuts in gold.With the development of technology, Microstella regulating is designed in its interior side. The two patents have 20-year period of validity. After that, any of watch brands can use these patents.

Accuracy of a timepiece is significant. Taking the ship’s clock as an example, accumulative voyage error will reach to 27 kilometers in two months if the clock speed is affected by one second per day. If a mechanical wristwatch daily error is more than 10 seconds, wearers can feel that obviously. What can make a wristwatch work more accurate? To adjust vibration period is the most direct and the most commonly used method, so the adjustment device appear significant and pivotal like an auto gearbox. Fine time adjustment is a critical component to judge the quality of a wristwatch or a movement. For a movement, the same model will be ranked, because it is equipped with different levels of adjustment devices. ETA movements equipped with different levels of balance springs, balance wheels, absorber devices and adjustment devices are divided into the Standard, Elaborated, Top and Chronometer. So are top movements.

What’s the fine adjustment?
A mechanical watch made up of at least more than one hundred components and parts seems sophisticated, but its actual principle is simple. The spring power is transmitted to the escapement mechanism through some groups of gears.The hands are assembled in the gear transmission device, and the rotation speed of the gears must be controlled well if accurate time is wanted. It’s the same as the truth that the tap control the water velocity. The task that controls the rotation speed of central hands falls on the terminal escapement mechanism, balance wheel, balance spring and adjustment device. What can affect the accuracy of a watch? The mechanical oscillator and the vibration period. The balance wheel and the hairspring swing back and forth, and the maximum angle is called peak-to-peak amplitude. How to control the amplitude or vibration period? Two ways. One is to adjust the actual working length of the hairspring with regulator pin, the most common way. The other is to adjust the balance wheel weight.

1. Regulator Pin
Regulator pin is the most commonly used to adjust the accuracy of a mechanical watch. That to truncate the length of the hairspring shorten vibration period drives a mechanical watch go faster. On the contrary, the vibration period get longer as the hairspring is lengthened, so the watch will go slower. The most typical regulator pin is made up of four parts: eccentric screw, V-shaped part on the head of vernier clip, hairspring stud and regulator clip. The way to adjust the length of the balance spring with regulator pin has birth defects. The regulator clip used to control hairspring working length can increase deformation of the balance spring when the spring is working. The part opposite to the regulator clip deforms the most seriously. The deformation will destroy elasticity of the spring, and it will cause instability of vibration. It’s very important for a mechanical watch to keep stable forever. In addition, regulator pin is easy to be affected by the change of spring torque, temperature variation and shock. This is why almost all chronometer movements use weight used on the balance and double-deck hairspring.These wristwatches with eccentric-screw regulator pin are not expensive. Among top watch brands, I’m afraid that only Ulysse Nardin has such watches whose movement are based on ETA models.