The balance. The central node, which regulates the accuracy of the clock.
Balance - is the central node, which regulates the course of the oscillatory system clock. It replaced the pendulums, which are strongly dependent on gravity, ambient temperature and atmospheric pressure.
In essence, before the balance sheet to ensure accurate course, the clock should keep immobility, ie, be table, floor or wall. That change allowed the pendulum to produce small-sized balances mechanisms, opening the era of portable clock. Balance sheet and coil invented in 1675 by the Dutch mathematician and physicist Christiaan Huygens.
The system of balance-helix consists of a balance with the axis, spiral pads, speakers, and adjust the accuracy of the device. A balance must move along an ideal circular path all of whose points lie in one plane.
Therefore, there are still balances with adjusting screws on the rim, whose main task - to establish a balance in the best position "to balance the balance sheet." Unlike compensatory screws, adjusting screws of the box will never touch.
In order to achieve a constant period of oscillation of the balance and, hence, the constancy of the error, it is necessary to minimize expansion and contraction of its rim when the ambient temperature. This is achieved by applying a special beryllium bronze alloy known as glyusidur (glucydur).
Earlier (but less effective) alternative to such a solution - the creation of bimetallic balance with a split rim. The outer layer is made from steel, and internal - of brass. When the temperature of the rim is bent, changing its size, and, consequently, the moment of inertia.
But the difference of thermal expansion coefficients of steel and brass makes the rim deform in the opposite direction and leads to the restoration of the original moment of inertia. Thus, there is an automatic adjustment of the clock in response to changes in ambient temperature.
The disadvantages of this design - the complexity, high cost of production and greater resistance to air. In addition, a pair of steel-brass is good, not all temperature ranges due to the nonlinearity of the thermal characteristics.
Bimetallic balance, which was introduced in the 40s of last century, were gradually pushed out of the balances glyusidura. This type of balance, a popular and today, has created a nearly ideal mechanism for adjusting the clock. Combination glyusidurovogo rim and a spiral of iron-nickel alloy (nivaroksa) can be found in virtually all mechanical watches of high quality.
Advances in technology made possible the manufacture of materials (for balances with a small period of oscillation glyusidura) a complete rejection of the adjusting screws. This is making the balance a more streamlined, reduced the resistance of air. Some manufacturers continue to use the balance with adjusting screws, but this solution is caused solely by the desire to make the balance more impressive appearance.
It would be desirable, however, be noted that all of the above applies to imported clocks. In our country, other materials are used. Thus, the rim is made from brass or nickel silver. It is hard to say what causes it, but probably some isolation of the USSR during the development of horology, and the presence of foreign patents that protect the use of new materials.
The spiral is inextricably linked to the balance. Together they form the oscillating system and are the "heart" of watches. Spiral - a thin strip of metal-lined, formerly made of steel or bronze, twisted in the shape of an Archimedean spiral.
Despite its name, hair (spiral) is actually three times thinner than a human hair. But despite the extreme thinness and weight, which rarely exceeds 0,002 grams, the spiral can ovladat with tension force of up to 600 watchmakers often use the phrase "breath spiral" to describe her pulsing cycles of contraction and expansion. Unusually resilient hair braided in a tight spiral and spins more than 200 million times a year.
Studies conducted in the 30's, led to an alloy of iron, nickel and chromium with the addition of a certain amount of magnesium, silicon, titanium and beryllium, known as "nivaroks" (the first letters of the German word nicht variabel, oxidabel - "does not change is not oxidized "). Reaffirming its name, the material differs in a number of remarkable properties. He has an extremely low coefficient of thermal expansion, and has anti-magnetic properties.
Spiral of nivaroksa capable automatically compensate for temperature changes, was first proposed in 1933. In the 40 years of quality bimetallic balance with spiral nivaroksa flooded the market. Nowadays, these spirals are used in all high-quality wristwatch. All the coils of hair balance today lie in one plane. The spirals are either the right or left wound.
The accuracy of mechanical watches is highly dependent not only on the material but also on the shape of a spiral. In the past, used the so-called bregetirovannye spiral. Abraham-Louis Breguet improved the properties of the spiral by changing its geometry by bending the outer loop up to a millimeter over the whole helix. In this case, the column is not in the plane of the helix, and above it.
The properties of the helix determine the consistency and fluidity of balance and quantity of the active site helix and the moment of inertia of the rim of balance - the period of its oscillation. That's why most watches equipped with a thermometer, turning that you can change the active length of the helix, ie, its stiffness. Elongation leads to a slowing of the clock, and shortening - to accelerate.
Another important detail - the bearing balance. The balance has a relatively large mass and becomes a significant positive and negative acceleration in the moments before and immediately after the change of direction of rotation. To cope with these forces, to mitigate the possible external shocks and tremors, as well as to reduce friction between the axle journal and the balance of their seats, watchmakers had to develop a complex two bearing system. Through-stone of balance and invoice Stone (toe) are installed at both ends of the axis of balance.
Thrust bearing is used to limit vertical movement of the balance, as well as to ensure the safety of liquid lubricant. The shank of each pin is polished and has the shape of a hemisphere, which helps to reduce friction. Inside the through there is an indentation in the stone - oiler, which retained hour oil. Moreover, the holes for pins drilled into the rock to the composite thrust bearing, are not cylindrical, and rounded shape, the so-called "olivazh" to ensure the least possible friction zone pins.
Most modern machinery is equipped with anti-shock device with locking a spring, which presses on the invoice and through the stones in the corresponding cup-shaped bearing, set in platinum. This spring can offset shocks and thereby prevent the trunnion axis of the balance sheet of Bounce in the bearing, or even from their failures.
Clock accuracy is most dependent on the design of balance. In typical arrangements balance fluctuates with a frequency of 5 vph (cycles) per second or 18,000 beats per hour. In the newer, more accurate clock balances fluctuate with the frequency of 19 800, 21 600, 28800 or 36 000 cycles per hour. In the majority of hours - and the Japanese, and Russian, as well as in many Swiss - 21 600 frequency is used. Frequency of 28 800 is used in some domestic and many hours of precise Swiss movements with a small period oscillation balance. Frequency of 18 000 used in the classic Swiss mechanisms, as well as in our "Vostok".
Adjustment mechanism includes a measurement of diurnal hours and, if required, its optimization at different temperatures and at different positions. Depending on the quality of the mechanism and the desired degree of accuracy, there may be various kinds of adjustments.
Standard setting good watch runs in two directions (up and dial up crown.) Deviations of transition between these two positions should not exceed 30 seconds per day.
For fine adjustment in accordance with the requirements of the factory mechanism should be regulated in at least five different positions. If the test is conducted officially recognized institution, and a number of parameters of the mechanism exceeds specified minimum value, the clock can be considered "officially certified chronometer." The vast majority of mechanical watches is the deviation of 30 seconds of the diurnal variation, ie error - only 0.035%.
To summarize, we do not exaggerate if we say that the vibrational system based on the balance sheet in a wristwatch, is one of the most successful inventions of time.
The system of balance-helix consists of a balance with the axis, spiral pads, speakers, and adjust the accuracy of the device. A balance must move along an ideal circular path all of whose points lie in one plane.
The spiral is inextricably linked to the balance. Together they form the oscillating system and are the "heart" of watches. Spiral - a thin strip of metal-lined, formerly made of steel or bronze, twisted in the shape of an Archimedean spiral.
Despite its name, hair (spiral) is actually three times thinner than a human hair. But despite the extreme thinness and weight, which rarely exceeds 0,002 grams, the spiral can ovladat with tension force of up to 600 watchmakers often use the phrase "breath spiral" to describe her pulsing cycles of contraction and expansion. Unusually resilient hair braided in a tight spiral and spins more than 200 million times a year.
Adjustment mechanism includes a measurement of diurnal hours and, if required, its optimization at different temperatures and at different positions. Depending on the quality of the mechanism and the desired degree of accuracy, there may be various kinds of adjustments. 
