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Mechanical watch


Mechanical watch
Creating a mechanical clock was of great importance for the history of technology. It's not so much that people have at their disposal a handy instrument for measuring time. The effect of this invention was much wider. Watches were the first machine created for practical purposes and widespread. For three centuries they were the most difficult and technical device, like a magnet attracts creative thought mechanics. There were other such art, where it would be applied as a brilliant ingenuity, knowledge and wit, as in the creation and improvement of the mechanism. So do not be an exaggeration to say that the XIV-XVII century in the history of art were marked by hours. For most art and its creators it was time to maturity. Compared with the same primitive devices, watches have become like a big qualitative step forward. Making them required complicated calculations and hard work, special tools and new materials, they provided an excellent opportunity to connect science and practice. Many design ideas, then got spread in other industries were first tested in hours, and for many mechanisms established in later times, the clock served as a model. They appeared as if all the experimental model of the mechanical arts in general. It is difficult to name even a device that gave such a rich field for the work of human thought.

Various devices for measuring time were created in ancient times. The immediate predecessors of mechanical watches, prepare them for the invention were water clocks. The complex water clock already used dial with moving arrow on it, the load as a driving force, wheel transmission, the striking mechanism and puppets, played out various scenes. For example, this technical masterpiece of its time was the water clock, presented to Charlemagne by the Caliph Harun al-Rashid. Richly decorated, they had a clock dial and every hour proclaimed sonic boom from a metal ball that bounced on the grille. At noon, in these hours, they opened the gate and went out of their knights. In medieval chronicles have many references and other witty designs water clocks. However, a genuine revolution in the art of timekeeping, and there was, as already mentioned, only after the wheel of mechanical watches.

The first mention of the wheeled tower clock in Europe accounted for border XIII and XIV centuries. Could these watches appear earlier? To answer this question, let us see some of the major components of a watch movement. Such main components can be divided into six: 1) engine; 2) of the transmission gear; 3) lights, creating a uniform motion; 4) distributor, or descent; 5) dial mechanism, and 6) the transfer mechanism and the winding of hours.

First timers driven by the energy of the descending cargo. The drive mechanism consists of a smooth wooden shaft and a wound on his hemp rope with a stone and later metal weights on the end. Through the power of the weight of gravity began to unwind the rope and the rotating shaft. On the shaft it had planted a large or main gear in mesh with the gears of the transmission mechanism. Thus, the rotation of the shaft of the mechanism passed hours.

Even before we mentioned that the wheel rotation period of gearing depends on the ratio of the diameter of the wheels belonging to it (or, equivalently, the relationship of the teeth). Selecting wheels with different numbers of teeth, it is easy to achieve, for example, to one of which revolves for exactly 12 hours. When applied to this wheel shaft arrow, then it will make a complete revolution in the same time. It is clear that just as you can pick up the wheel, making a complete revolution per minute or per hour; You can connect with them momentary and minute hands. But the hours were much later - only in the XVIII century, and before that used only one hour hand. Assigning a transmission mechanism composed of hours to convert and transmit properly the movement from the main gear to the hour wheel.

However, to watch could serve to measure time, the arrow should make its momentum with the same frequency. Meanwhile, the goods, as is well known, is moving under the action of gravity acceleration. If the weight is dropped freely, the shaft would rotate rapidly, the arrow would be made accordingly every next turn in a shorter time than the previous one. Faced with this problem, medieval mechanics (although they do not have a clue about acceleration) realized that the clock can not only depend on the movement of cargo. The mechanism had to be supplemented by another device. The device was to have its own, independent "sense of time" and in accordance with that control the movement of the whole mechanism. Thus was born the idea of ​​the regulator.

If modern man to ask a very simple tool would be best used as a regulator, it is likely to call the pendulum. Indeed, the pendulum best meets the conditions imposed. This can be seen by making a simple experiment. If a ball tied to a sufficiently long thread to reject a small angle and let go, it will start to oscillate. Armed with a stopwatch, you can count the number of oscillations of the pendulum will make, for example, for every fifteen seconds. Continuing surveillance and a half or two minutes, it is easy to note that all measurements are the same. Because of air friction ball swing oscillations will gradually decline, but (and this is very important!) The duration of vibrations will thus remain unchanged. In other words, the pendulum has a wonderful "sense of time." However, for a long time, these remarkable properties of the pendulum mechanics were unknown, and pendulum clocks have appeared only in the second half of the XVII century. The first mechanical clock controller served as a rocker (bilyanets). Follower since ancient times been used in such a widespread device, like scales. If each arm of a beam balance put equal weights and then bring the scales of balance, the rocker will make quite equal vibrations like a pendulum. Although this oscillation system is inferior in many respects to the pendulum, it may well be used for the clock. But any control, if not permanently maintain its fluctuations, sooner or later stop. In order for the clock to work, it is necessary that part of the motive power from the main wheel is constantly came to the pendulum or bilyantsu. This task executes in clock device, which is called the distributor, or descent.

The descent has always been and remains the most complicated assembly in a mechanical watch. Through him, communication between the controller and the transmission mechanism. On the one hand, the descent transmits shocks from the engine to the regulator required to maintain the latter oscillation, and on the other hand, the subordinate gear movement (and hence the operation of the engine) control laws of motion. The correct course of hours depends mainly on the descent. It was on his design the most puzzled inventors. The first descent was a spindle with a touch, so it is called the spindle. On the principles of its operation will be explained in detail below.

In the first hours there was no special winding of the mechanism. As a result, training hours required to work a lot of effort. Not only that, several times a day had to be lifted to a considerable height the weight is very heavy, it was necessary also to overcome tremendous resistance of the gears of the transmission mechanism. (It is understood that the main wheel, if it is rigidly seated on the motor shaft, when lifting weights will rotate with the shaft and with it will rotate and the other wheels.) Therefore, in the second half XIV century main wheel become fastened in such a way that when reverse rotation of the shaft (counterclockwise) it remained stationary.

Of the six we have described the main components of the large clockwork alone has been used in antiquity. The new invention were only two: the idea to hang the load as the engine for hours, and the idea of ​​using the spindle as the descent. It is interesting that both these technical findings medieval legend attributes to one person - the scientist Herbert Avrilakskomu monk, who later became pope under the name Sylvester II. It is known that all his life, Herbert is very interested in clocks and 996, I gathered first in the history of the clock tower of the city of Magdeburg. Since the clock is not preserved, the question remains to this day - a principle of action they had. Most modern scholars believe that they were water. In favor of this speaks also the fact that following the clock tower, which with more or less reason can be considered mechanical, appeared in Europe only in three hundred years. However, on the other hand, when Herbert was really such a good mechanic is written about him, if he really invented the spindle running and if it is really a lot of thought over the scheme of mechanical watches, it is unclear what could prevent him to collect such hours as he had all you need to do.

But be that as it may, the era of mechanical watches began in Europe only in the end of XIII century. In 1288 the clock tower was installed in Westminster Abbey in England. In 1292 the clock got a church in Canterbury. In 1300, a message is encountered that the clock tower built in Florence (references about this watch is preserved in the "Divine Comedy" by Dante). In 1314 the clock was already in Cannes. None of these early arrangements has not survived to the present day, the names of their creators, too, are unknown. However, we can accurately imagine their device. The easiest clock mechanism (if not to take into account the striking mechanism) may include only three gears. It is obvious that all the hours mentioned above is an example of a simple three-wheeled mechanism with single-needle dial.

From the main wheel landed on the motor shaft, the movement is transmitted to the small gear is on the same axis as the crown (or screwed) wheel that has been provided with teeth having a sawtooth shape and the perpendicular axis of the wheel. This wheel has been an integral part of the trigger, or spindle descent, who had the task of speed gear train traffic control. Crown wheel, receiving power from the gear, spent it on the spindle rotation, with which it is in constant communication. The spindle was equipped with two pallets placed on it against the bottom and top of the tooth crown wheel. Pallets with respect to each other were placed at 90 degrees and alternately hooked prongs crown wheel, causing rotation of the spindle with the pallet into one or the other side. When, for example, protruding tooth wheel faced pallet bottom and impinges on it, it is led to the spindle rotation on its axis and thus to ensure that the upper pallet over time entered into the gap between the teeth located in the upper part of the wheel. The pressure exerted by the upper tooth has changed to reverse rotation of the spindle. the escape wheel tooth each time such a rotation of the spindle freed. But the wheel immediately get in touch with another pallet, and so the whole process was repeated again. With each turn of the wheel spindle turn kept pace with only one tooth. spindle rotation speed is determined by the regulator, which is, as already mentioned, the rocker with moving loads on it. When goods moved closer to the axis of the spindle begins to turn faster and the clock accelerated its move. When goods moved closer to the edge - the clock is slowed down.

This was the concept of early mechanical clocks. But very soon their device much more complicated. the number of gear wheels primarily increased. Caused by it was the fact that when a significant difference in the number of teeth between the driving and driven wheel gets very large gear ratios, the mechanism felt a heavy load and wear out quickly. The load in these hours fell very quickly and had to raise five or six times a day. In addition to the creation of large ratios required wheel diameter is too large, which increased the size hours. Therefore we began to introduce additional intermediate wheel, whose task was to increase the ratios smoothly.

Let's see, for example, on the device clock de Vic, established in 1370 at the Royal Palace in Paris. Around a wooden shaft A, about 30 cm in diameter, was wrapped around the rope with weights at the B end. Weight of about 500 pounds (200 kg) dropped from a height of 10 m for 24 hours. Giri much weight required due to significant friction in the wheel engagement and the presence of heavy-bilyantsa regulator. All items were made by blacksmiths hours on the anvil. A shaft was located on the main wheel E, which aired the rest of the rotation mechanism of the wheels. To facilitate the winding of the coupling shaft is not hard, but by the pawl ratchet wheel F and G. Thus, rotating clockwise, the shaft is set in motion the wheel E, as spinning counterclockwise, leaving him free. For winding of hours served gear C, concatenated with gear D. It is easier for a turn of the handle. Big wheels are driven by gear sitting on the shaft, which was the second wheel - H, and the latter are driven by a gear wheel, located on the axis where the third sitting, or the escape wheel spindle descent I. J with a yoke of N and K Pallet acted It is the same as described above.

The tower clock mechanism were quite capricious, requiring constant supervision. The cargo had to raise several times during the day. The clock dependent on the friction force, so they need constant lubrication. Accuracy their daily course by modern standards, was very great. But, despite this, they have long remained the most accurate and advanced instrument for measuring time. With each passing decade, the clock mechanism was complicated. With the clock began to bind a variety of other devices, perform a variety of functions. In the end, the clock tower turned into a complex device with many arrows, automatic moving figures, varied combat system and stunning decorations. These were masterpieces of technology and art at the same time. For example, the famous master Dzhunello Turriano took the wheel in 1800 to create a clock tower, which reproduces the movement of Saturn day, hour of the day, annual motion of the sun, the movement of the moon and all the planets according to the Ptolemaic system of the universe. In other hours puppets played real theater. Thus, in the Prague clock tower (constructed in 1402) before the fight revealed two small window above the dial and they came out of the 12 apostles. A terrible figure of Death, standing on the right side of the dial, with each fight hours turned the scythe, and then an hourglass, recalling the end of his life. A man standing nearby, nodded his head, as if to emphasize the fatal inevitability. On the other side of the dial are two more figures. One depicts a man with a purse in his hand; each hour he rang coins lying there, showing that the time - money. The other figure portrayed traveler uniformly strikes his staff into the ground. It shows how over time is moving on the way of life people, or the vanity of life. After the battle watch a cock appeared and shouted three times. The last appeared in the window Christ and the blessing of all the spectators standing at the bottom. The development of such machines require special software devices. They set in motion a large disk, with a clockwork mechanism. All movable parts of the figures had their arms. During rotation of the circle, they rose and fell when the levers fall into the special notches and teeth of a rotating disk. In addition, the clock tower had a separate mechanism to fight (many hours different repulsed quarter of an hour, an hour, noon and midnight), driven by their own weights, and four of the dial (on each side of the tower).

By the second half of the XV century are the very first mention of watchmaking with a spring motor, which opened the way for the creation of miniature clock. The source of the driving energy in the spring hours served the institution and tends to turn around the spring, which is a flexible, carefully hardened steel strip, rolled around the shaft inside the drum. The outer end of the spring was attached to a hook in the wall of the drum, inside - joined to the drum shaft. In an effort to turn around, the spring drives the rotation of the drum and its associated gear, which in turn convey the movement system of gears to control inclusive. Constructing such a watch, the master had to resolve several technical challenges. The main one concerned the operation of the engine. After all, for the right of the clock spring should for a long time to work on the wheel mechanism with the same force. To do this, you must make her turn around slowly and evenly. The impetus for the creation of the spring clock was the invention of constipation precluded spring straightened immediately. It was a little latch is placed in the teeth of the wheels and allows the spring to unwind the only way that simultaneously turned her whole body, and with clockwork wheel him. Since the spring has an unequal effect on the elasticity of the different stages of its deployment, the first watchmakers had to resort to a variety of clever tricks to make it move more uniform. Later, when we have learned to produce high quality steel for watch springs, they no longer need. (Now watch cheap spring just doing long enough, calculated approximately 30-36 hours, but the recommended wind the watch once a day at the same time. The special device prevents the spring when the plant curl to the end. As a result, spring travel is used only in the middle part, when its elastic force more uniform.)

The most significant improvements in the clock mechanism was introduced in the second half of the XVII century the famous Dutch physicist Huygens, create new controllers for the spring, and for Kettlebell hours. To use it for a few centuries, the yoke had many shortcomings. It was even difficult to call control in the proper sense of the word. After all, the regulator must be able to self-oscillations with the natural frequency. The rocker was also, generally speaking, only the flywheel. Many extraneous factors influence on his work, which affects the accuracy of the clock. The mechanism has become much more advanced, when as a regulator started using a pendulum.

For the first time the idea to apply the pendulum in the simplest instruments for measuring time came the great Italian scientist Galileo Galilei. It preserved the tradition that in 1583 nineteen Galileo, being in the cathedral of Pisa, drew attention to the swinging chandeliers. He noted, counting the beats that during one oscillation chandeliers remains constant, even though the scope is smaller and smaller. Later, engage in serious study of pendulums, Galileo found that at small span (amplitude) swinging (only a few degrees), the oscillation period of a pendulum depends on its length and has a fixed duration. Such variations came to be called isochronous. It is very important that the isochronous oscillations of the oscillation period of a pendulum is independent of its mass. Because of this pendulum was very convenient instrument for measuring small time intervals on the basis of its Galileo has developed some simple counters that are used during their experiments. But due to the gradual attenuation of the pendulum oscillation could not serve to measure long periods of time.

Creating a pendulum clock pendulum consisted in connecting the device to maintain its oscillations and their reference. At the end of the life of Galileo began to design such a watch, but further development did not get. The first pendulum clock was created after the great scientist's death his son. However, the device of this watch was kept a closely guarded secret, so they did not have any impact on the development of technology. Regardless of Galileo in 1657, mechanical pendulum clock, Huygens collected. When replacing rocker arms on the pendulum of the first designers are faced with a difficult problem: as already mentioned, the pendulum makes isochronous oscillation only at a low amplitude, whereas the spindle descent demanded a large scale. In the first hours of Huygens pendulum swing reaches 40-50 degrees, which adversely affects the accuracy of stroke. To compensate for this shortcoming, Huygens had to show the wonders of ingenuity. In the end, he created a special pendulum that during the swing changes its length, and hesitated for a cycloid curve. Watch Huygens had incomparably greater accuracy than the clock with a yoke. Their daily error does not exceed 10 seconds (in hours from the rocker control error ranged from 15 to 60 minutes).

Around 1676 English watchmaker Clement invented the anchor, anchor escapement, which is very well suited to the pendulum clock, which had a small oscillation amplitude. In this design, the descent to the pendulum axle to sit down with the anchor pallets. Swaying with the pendulum, the pallets are alternately introduced into the impeller, subjecting it to the period of rotation of the pendulum swings. With each swing turn wheel kept pace with one tooth. Due to such a trigger pendulum receive periodic shocks that would not let him stop. Push occurred whenever the impeller, liberated from one of the teeth of the armature strikes with a certain strength of the other tooth. This push was transferred from the armature to the pendulum.

Pendulum regulator Huygens made a genuine revolution in the art of watchmaking. Later Huygens lot of trouble on the improvement of pocket spring hours. The main problem that was at the time in front of watchmakers was to create a self-regulator for pocket watches. If stationary tower clock rocker considered suitable enough, then that could be said about the pocket watch, which is constantly in motion, swayed, shook and changed their position? All these variations have an impact on the course of hours. In the XVI century watchmakers were replaced dvuplechny bilyanets a rocker circular wheel-mass flywheel. This has improved the working hours, but it is still not satisfactory. An important improvement of control occurred in 1674, when Huygens attached to the wheel to the flywheel-spiral spring-loaded - hair. Now when you reject the wheel from the neutral position hair I worked on him and tried to return to the place. However, the massive wheel slipped through the equilibrium point and spins the other way as long as the hair again did not return it back. Thus the first balance knob or rocker with properties similar to those of the pendulum was created. Unbalanced state, the wheel balancer began to oscillate around its axis. The balance was a constant oscillation period but unlike the pendulum could operate in any position, which is very important for pocket and wristwatches. Improvement Huygens made among spring hours of the same revolution as the introduction of stationary pendulum wall clock.

The new regulator has demanded a new shutter design. In the following decades, various watchmakers have developed several ingenious launching appliances. The most simple cylindrical trigger for spring clock was invented in 1695 by Thomas Tompion. Tompion escape wheel was equipped with 15 special shaped teeth "on legs". Sam cylinder is a hollow tube, the upper and lower ends of which were tightly packed with two swabs. On the lower rocker swab was planted with hairs. When oscillation of the balance to the right and to the left in the appropriate direction and spun the cylinder. On the cylinder was cut in the 150-degree passing at the level of the escape wheel teeth. When the wheel is moved, his teeth alternately one after another entered the cylinder cutout. This isochronous movement of the cylinder escapement wheel and passed through it - the whole mechanism and balancer receives an impulse, supporting his hesitation.

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