Do-it-yourself stopwatch repair

Our watch workshop repairs not only wrist, grandfather and wall clocks. Also, the range of services includes the repair of alarms, stopwatches, pocket watches.

The difference between alarms and desk clocks is a device for giving an alarm at a specified time. Alarm clocks are:

• Mechanical.
• Electronic and mechanical.
• Quartz.
• Electronic.

The pocket watch is powered by a mainspring located in the barrel.

The stopwatch mechanism is no different from a regular watch. But there is an additional mechanism for returning the arrows to their original position.

The following defects are encountered in the stopwatch mechanism.

1. Due to the fact that the crown is fixed on the thread, and the threaded part of the shaft is sharpened, then during winding of the stopwatch spring, the crown may sink deeper along the thread, which will somewhat shorten the working part of the shaft.

In this case, unscrew the head and insert a piece of metal into the head sleeve, from which the head rises higher.

2. The crown wheel pad has worked. This causes the repair wheels to crackle. It should, the crown wheel screw lower or replace the lining.

3. Double hammer for changing hearts does not fit closely to hearts. In this case, it is necessary to slightly rivet the ends of the hammer or saw off the protrusion that interacts with the column.

4. There are cases when the complication of the stopwatch is in full working order, however, when the hands are reset to zero, the second hand does not reach its original position and each time moves further and further from the zero position. You should fasten the second hand to the tube or squeeze the tube of the second hand so that it sits more tightly on the sleeve of the heart.

5. If the arrow goes up and does not rotate with the axle, remove the retaining spring and slightly deepen the bushing recess so that the spring goes deeper into the groove. This improves the fixation of the heart on the • axis.

In some stopwatches and in watches with a stopwatch, chronograph wheels are used, with which cores are mounted on the same axis, designed to return the hands to the zero position. This assembly (chronograph wheel, heart and hand) must be balanced by drilling a hole in the wheel sector.

If the hands are difficult to remove, then the dial is removed along with the hearts and hands. Hearts that do not require special repair are cleaned with a dry brush. The holes in the hearts are cleaned with a pointed chock and blown with a rubber bulb. If the hands are not removed, then when disassembling the mechanism, the lever of the double hammer is removed from the heart during the installation of the dial.

During the assembly process, the axle pins and the working surfaces of the trigger mechanism are lubricated with oil. When adjusting the starting device, it is necessary to achieve the movement of the locking pin in an arc so that the pin, after releasing the balance, would give an initial push to the balance. To small

the friction spring worked reliably, it is necessary to ensure proper pressure on the axle. For these purposes, they often resort to its additional bending.

Arrows must be properly fitted. Set the arrows at the zero position of the hearts.

Where to begin. Some notes from Bogdan J.

This is purely the experience of an amateur who has never been a professional watchmaker. Accordingly, all this is suitable for the amateur. A professional is dear to the school. They will teach everything there.

Start with Pinkin. Or from Troyanovsky. In general, there are books on the topic of clock repair. Download and print.Okay, there is no Internet - everyone will do it for you in any Internet cafe. You must have a book. It can get expensive but well worth it. This book is a guide for the layperson who should be able to understand at least something from this book. Almost our case. I have never done anything like that - and here it was.

Let's make some additions with the amendment for today for those who are pinned.

Screwdrivers. Start simple.

Chinese. I use it. I sharpen it. As for Chinese screwdrivers - look where on the streets watch batteries are changed and batteries and watch straps are sold. Or in the most ordinary households. A set of screwdrivers for small jobs.

You take a screwdriver. If it turns out to be too soft and bends when trying to unscrew something, put a candle next to the screwdriver. You heat the blade of a screwdriver and quickly into wax. This is hardening. Then you take a small stone and sharpen it along Pinkin.

More cool - in a machine on a diamond disc. But it will be later. When the tool and machines appear. Stones are well suited for finishing.

Tweezers (for starters - medical eye tweezers will do).

An alternative is to get acquainted with a radio bazaar (if Moscow - it seems Gorbushka - where they sell radio components, radio stations and computer gadgets) - see the boxes where the instrument is sold. You will be greatly surprised by the abundance. Good tools are surprisingly expensive. Tweezers shapes - see Pinkin. I'm not talking about big watch shops. They would rather be beaten than sold at a normal price. They do not want to breed competitors. And if they do, the prices are simply unrealistic. Doesn't fit into any gate.

There is also a radio bazaar - Galosha gasoline. Wash. It is much drier than kerosene and white spirit.

You take sticks (like Chinese) - finger length - to taste. You stick fishing steel 3-4 cm long into the end - it can be thicker and thinner. 0.1 - 0.15 mm. This is for the fishermen. One meter is enough for 10 years of work.

The very tip with one blow of a hammer (through a punch or a hard piece of iron) is splashed on a hard anvil. You get a little spatula. You make 3-4 of these with different blade sizes and different steel diameters. This will replace butter dosing. As anvils, I use either a roller made of a large bearing or carbide plates for a lathe - your way to the flea market or to friends in the workshop.

In approximately the same way - they will come in handy for a start - sticks with ordinary sewing needles - while the hands are frightened and there are no good tweezers - to expose the details (gears in stones, screws, etc.) is an auxiliary tool.

Surgical clamps. Different. Very handy as small and strong pliers. They are usually bought on occasion at a flea market.

Dental spatulas. It is convenient to use in all cases as an auxiliary tool.

Enema. Rubber. From the pharmacy. Big. Blow off dust. The tip must be rubber.

Butter. Or in the workshop (if they don't beat you, although they usually look like rams and pretend that they don't understand what you are talking about at all and are trying to get you off as quickly as possible). Or maybe at a radio store - in the same place where solder and acid are sold. Oil MN-30, MN-45 or watch oil. Although it is not aerobatics, it will go for a start.

It is better to keep it in a dark heavy box - and the sun will not burn and there is less chance that it will turn over.

To open the cases - a large, broken medical tweezers. It is clear that this is not kosher - but it is also possible. Likewise - an old caliper. You just need to correct the edges of the jaws - so that they are more rectangular.

Scalpel - opening of enclosures.

Binocular loupe. It is relatively inexpensive, but without it it is better not even to start. Or photographic goods (classic - where telescopes and binoculars are sold) or a radio bazaar. There are different strengths. If you have money, take two. One is 1.5 times, one is the strongest one sold - it seems up to 2.5 times.They can be sold with an elastic band - you will have to redo them to fit a hard bezel. You can go and talk to the optics workshop - glasses. Maybe they will offer something like pince-nez. Regarding ordinary magnifiers - to my taste - I rarely use them. It turned out to be extremely useful for cutting off the baby's nails - they were not visible at all for the first six months, but it was necessary to cut them off.

Binocular - microscope. Yes. Old. Look. The oldest is MBS-1. It is with a straight image - not upside down - which is what we see. It should cost within $ 50. A very useful thing. In every way. Up to the point that you rip the scrap out of your finger. But this is on occasion and over time. MBS-10 or OGMZ is steeper - the distance from the object to the eyepiece is greater, it is clear that it is more expensive. But all the same, an ordinary screwdriver does not fit under the MBS-10 - it must be shortened. Although on the Site of the Lytkarinsky plant - the manufacturer of MBS-10, there is a link that they sell lenses for MBS-10 with a distance to the object - about 19 cm.This can be a good solution if we got MBS-10. Everything between MBS-1 and MBS-9 is the same. Over time, the lens can be altered by yourself. You take what is cheaper. It's closer to the flea market. The only thing is that it is desirable that there is an illuminator (transformer + light bulb).

All that is further from the instrument - only after evisceration for 4-5 hours.

Where to get a watch - make yourself a fashion to be at a flea market - everything floats there. Often they simply sell mechanisms there. For instance:

When you warm up a little - after buying a binocular microscope - there is also a radio bazaar, shops with tools - they usually sell ultrasonic cleaners. But here is also the question - is it necessary. 50 years before that they did not use them - they took a bath and washed the parts with a brush in gasoline. You can do it, but the weight is not bad. Should cost in the range of $ 50-80. Denatured alcohol and Galosha gasoline were poured into an ultrasound of 30 watts. Working. Does not flash. Washes like a beast, but all the same, sometimes you have to rip something off with a toothpick. At the bazaar, they say that 30-watt sinks - indestructible - work without problems and there is no return due to marriage. If the model is the same as in the figure - what should be done after purchase - disassemble completely (there may be moisture inside, one of the indicators is stylish clicks when working against a background of uniform sound), squeeze the metal tank out of the case and put it back on the Auto Sealant (white , ours, not on transparent silicone). Plumbing does not work - it is highly corrosive. One of the indicators of plumbing is a strong vinegar smell.

Yes, I forgot, a flea market - look for Petri dishes - or maybe in a pharmacy or in a laboratory at a hospital. But you are not their client - there is an expensive flea market - this is the very thing. These are flat round glass or plastic low trays - for details. They are cheap. Take 5 pieces for the current dismantling works. I like glass more - they are heavier, fidget less on the table.

Then, for convenience, in the offices that make business cards, you can sometimes roll up and buy boxes for business cards. Wholesale will cost within $ 0.30 pcs. Transparent ones are also a very convenient thing - but this is for longer storage.

Silica gel. Small bags that are put into new fashionable shoes, equipment, computer components. Absorbs water. It must be dried either in the microwave or at a good temperature - in an electric oven. Gas does not pass - when the gas burns, water is released. After drying, the bag is placed in a box in which small tools and spare parts are stored for a long time so that they do not rust.

Radio bazaar. Snap-on pouches - they sell in the hundreds. Size 4 X 6 cm. Place watches and small items. They are usually packed with small pieces that are sold in the bazaar.

To begin with, the wristwatch can be laid down on the grinder mesh during disassembly. Then you yourself will determine what you need and how it is more convenient for you. The stand can be machined out of brass. Should be heavy enough.

Take a coil from any old starter from electricians - try asking for 380 V. If not, by 220 V.You attach the wires - the demagnetizer is ready. Turn on only for a short time - it gets warm.

About a new instrument. It is not always worth the money. Think how to get out with what you have. It is needed if you make a living with this and the customer pays for everything. If this is a hobby, then not first of all. Calculate the costs like this: I quit smoking (and drinking) and all the savings - on the tool. In this case, it is really a hobby and a useful pastime.

Now the steepness has gone. Machine.

Option 2. High-speed car. 10,000 revolutions. We sharpen with a diamond file. It may well be. There are eagles who did something in this way. But as for me - this is not very correct. If sharpen then sharpen.

Considering the above - if you do not sharpen the axes how to fry pies - then for a non-professional watchmaker-turner, it would be more expedient to take a small-sized precision universal machine. I would say that 20% of the work is axle turning (or even less), 80% is the turning of screws and body parts, various secondary milling work.

Examples I would name the following:

Collet chuck, native collets. On top is a milling corner. A part of the caliper is attached to it and we get a "milling cutter".

- new - Proxxon PD-230 / E, including a milling attachment or FF-230 router. Search on There they even have a price list in the power tool section - that is, they really do it.

Regarding the old MD-65. Axes 0.1 sharpens. Doesn't hit. Any additional clarifications are superfluous.

Now for the next topic. Okay. We got a machine. Well kva. We have a type of computer in the form of a processor, monitor and keyboard. But all this locomotive also needs software. Windows-2000 or Windows-XP and for tough peppers Linux will do. So, the fun begins. Software often costs more than hardware. It's the same story with machine tools. We need fixtures and additional tools. I think that an approximate set of additional accessories for the machine will cost no less than the machine costs. We are now talking about turning + milling. I ended up with MD-65 with a milling angle plate - a milling cutter is clamped in the machine chuck, and the support is turned over like a milling table, only a vertical one + milling vise. The arrows on it are milled. Cut the slots in the screws too.

- incisors - at least a hundred. Fits well in old wooden school boxes.

For precise sharpened incisors, old boxes from under grandmother's silver spoons go very well - incisors are more expensive than spoons, they will not break.

- collets and collet chuck. I have 2 sets - one is native to MD-65 (3-13 mm), the second set is Lorsch (hour, 0-6 mm).

It is in the machine, Lorsch in the adapter.

- indicators. 0.01 and 0.001. It is clear that various attachments are needed for them. Often you have to do the fasteners yourself.

- center detectors - 0.01. Without it, there is simply nothing to do on the machine.

- binocular microscope. Without words. We have already talked about this above.

- 4-jaw chuck. With split jaw release.

- sharpener - sharpen the cutters roughly

- diamond wheels - sharpen cutters precisely

- rotary vise (horizontal rotary system) - drill holes in precisely specified places. Screw holes in the rim of the transparent case back. It is hand drilled. It can be seen that the screws are jumping.

- dividing head. Or with discs or vernier. Cutting gears. Or at least make a square.

- I'm not talking about cutters. And end and for gears. The thickness of the disc cutters - from 0.1-0.15 - is the thickness of the "Neva" blade.

- the measuring tool is for rough work

- and for precise ones - only optics

- then you need to look at what is needed already for the work being performed. You will have to do a lot yourself. To invent a lot. Very often, for the manufacture of one part, it takes more time to make a clamp in order to clamp this part into the machine.

Foil trimming - making a "disk" arrow. Materials at hand.

Now the conversation is where and how to organize all this. It should be dry. Dust free. Not on the head of the family - the family should know that it is yours - and no matter what you do there - they have no entrance there. And there is nothing to howl about the noise from the workshop. Their comments are inappropriate (oh, it's dirty, oh, it stinks with gasoline).

One type I saw a German machine - the type of our school. More precisely, only pre-war. He mounted it under the kitchen table. In the center of the table is a shelf with a machine on it. The top board of the table rises - like in old school desks. He lowered the board, put the tablecloth in place and crumble the onion with the sausage. All the same, there will be no big turning works at home - everything is some kind of small piece.

If we are talking about a large workshop or a more serious occupation in the restoration business for the soul, then in addition to the small machine, you need to look towards a larger machine - a school one (I don’t want to name the type - there are many different ones), a horizontal milling NGF-110 and a muffle furnace - this is for more rough work and the manufacture of devices. It is clear that all this also needs a trailer of devices and tools. Photo of the basement in the country.

If you can order or buy somewhere, look towards the rollers. They can be quite expensive. Sometimes they help out a lot. Especially in the manufacture of new parts, arrows and shims for lathe cutters.

As a conclusion, let's put it this way - this process is endless. In one sensible book on choosing a watch lathe, there was a good idea, completely applicable in our case - we are all mortal. All these tools are of interest only to us. Personally. There is no need to expect that someone after us will continue with fire in their eyes what we have begun. The whole instrument must be bought on the basis that after us, our grateful descendants die of all this rubbish and faster. They can also be thrown into the trash. They need a place for a geranium! We need to make sure that they can get more for it, slowly and confidently to all these numerous relatives and posterity, it is necessary to explain that all this is expensive and on this in distant times it will be possible to earn something. And accordingly, if you already buy, then buy a liquid instrument, which will have a price even in 50 years. This is on the one hand. On the other hand, we are all working now. We earn something. This is exactly the right time to prepare for yourself a range of activities for a time when our earnings will decrease, that is, retirement. Good luck.

Stopwatches are devices designed to measure short periods of time, on the order of tens of seconds and fractions of a second. Depending on the purpose of use, there are 4 one-hand and two-hand stopwatches, three-, six-, ten- and three-tsatisecond, sixty-second, etc.

The structural diagram of a conventional one-hand stopwatch with respect to the structure of the main units (engine, transmission, balance regulator) is similar to the diagrams of wrist and pocket watches. However, starting, stopping and resetting the hands to zero is carried out by a special mechanism located under the dial and called a complication.

When stopping and starting the stopwatch, braking and release of the balance is carried out. This type of stopwatch is called a choppy stopwatch.

There are also stopwatches with a continuous stroke, in which the mechanism works continuously, and the complication turns on and off only the pointer mechanism.

Typically, the stopwatch dial contains 60 second divisions, less often 100 divisions. At the top of the dial there is a small scale with divisions of 10, 30 or 60 min. There is a hole in the center of the dial, into which the second's heart sleeve enters; the seconds hand is pushed onto this sleeve. On the small scale of the dial there is a minute hand, which is installed on the sleeve of the minute heart.

The stopwatch works periodically.The stopwatch is started by pressing the crown, which transmits the movement to the starting lever through the winding roller.

When the crown is pressed again, the stopwatch stops; when the crown is pressed a third time, the hands return to their original position.

In fig. 211, a shows the complication of the mechanism at the moment when the hands are in the zero position.

The control lever system of the complication (Fig. 211.6) is carried out by a ratchet wheel 5 with twelve teeth, carrying four columns.

To start the stopwatch, press the crown with your finger, which causes the ratchet wheel to turn with the starting lever 2, when the crown is released, it, together with the lever under the force of the spring 7, returns to its original position.

Lever arm 2, lowering its lower plane, turns the ratchet wheel by one tooth, at this time the spring 6 the ratchet wheel falls on the next tooth. During the rotation of the ratchet wheel, its first column will also turn to the right. The latter, in turn, presses on the ledge a double hammer 8 and lifts it so that it is a spring 11 pressed against the hearts. Ledge a is installed on a raised corner of the first column due to which the double hammer releases the hearts 9 and 10.

Simultaneously with the rotation of the ratchet wheel, the balance brake 12 spring action 14 with its protrusion from the second column falls into the cavity between the second and third columns and releases the balance 15, pinned 13.

Thus, the stopwatch was launched: the hearts began to rotate, the second and minute hands rotate with them.

Rice. 211. Stopwatch scaling position:

o - when the arrows are set to zero; 6 - when the stopwatch is on; v - when the mechanism stops: 1 - winding roller; 2 — starting lever; 3 — shoulder screw; 4 — the column of the trigger lever; 5 - ratchet wheel with four columns; 6 - thrust spring; 7 - spring of the starting lever; 8 - double hammer; 9, 10 - cores; 11 - double hammer spring; 12 - balance brake; 13 — brake pin; 14 — brake spring; 15 — balance; 16, 17 — spring of hearts; G - when the arrows return to zero position; 1 - heart; 2 - double hammer plane

In order to stop the stopwatch mechanism, press the crown again, the lever will lower and move the ratchet wheel one tooth forward, at this time the protrusion a the double hammer will be in the middle of the plane of the first column, and the brake lug falls on the corner of the third column. Thereby the pin 13 will go down and slow down the balance 15 (Fig. 211, c). The mechanism will stop and the double hammer 8 will remain in the raised position.

To return the stopwatch hands to their original position, you need to press the crown for the third time, while the lever will turn the ratchet wheel by one aub, at this time the protrusion of the double hammer 8 falls into the cavity between the first and second columns. Thereby the double hammer 8 spring action and will go down, hitting the planes on hearts 9 and 10.

The design of the knots of the minute and second hearts is the same. Heart springs 16 and 17 with one end they enter the recess of the axis and with the other they touch the sleeve of the heart, fixing the heart on the axis. In addition, the spring acts as a friction clutch in this case. So the springs 16 and 17 perform two functions: they press the heart against the axis, ensuring the rotation of the heart along with the axis and do not allow the heart to arbitrarily rise up.

The stopwatch clock returns to its original position. (The correct position of the plane of the double hammer in the zero position is shown in Fig. 211, d).

REPAIR OF STOPWATCHES

The following defects are encountered in the stopwatch mechanism.

1. Due to the fact that the crown is fixed on the thread, and the threaded part of the shaft is sharpened, then during winding of the stopwatch spring, the crown may sink deeper along the thread, which will somewhat shorten the working part of the shaft.

In this case, unscrew the head and insert a piece of metal into the head sleeve, from which the head rises higher.

2. The crown wheel pad has worked. This causes the replacement wheels to crackle. It is necessary to lower the crown wheel screw or replace the lining.

3. Double hammer for changing hearts does not fit closely to hearts. In this case, it is necessary to slightly rivet the ends of the hammer or saw off the protrusion that interacts with the column.

4. There are cases when the complication of the stopwatch is in full working order, however, when the hands are reset to zero, the second hand does not reach its original position and each time moves further and further from the zero position. You should fasten the second hand to the tube or squeeze the tube of the second hand so that it sits more tightly on the sleeve of the heart.

5. If the arrow goes up and does not rotate with the axle, remove the retaining spring and slightly deepen the bushing recess so that the spring goes deeper into the groove. This improves the fixation of the heart on the axis.

In some stopwatches and in watches with a stopwatch, chronograph wheels are used, with which cores are mounted on the same axis, designed to return the hands to the zero position. This assembly (chronograph wheel, heart and hand). Must be balanced by drilling a hole in the wheel sector.

If the hands are difficult to remove, then the dial is removed along with the hearts and hands. Hearts that do not require special repair are cleaned with a dry brush. The holes of the hearts are chiselled with a pointed chock and blown with a rubber bulb. If the hands are not removed, then when disassembling the mechanism, the lever of the double hammer is removed from the heart during the installation of the dial.

During the assembly process, the axle pins and the working surfaces of the trigger mechanism are lubricated with oil. When adjusting the starting device, it is necessary to achieve the movement of the locking pin in an arc so that the pin, after releasing the balance, would give an initial push to the balance. For the small friction spring to work reliably, it must be properly pressurized against the axle. For these purposes, they often resort to its additional bending.

Arrows must be properly fitted. Set the arrows at the zero position of the hearts.

CHRONOGRAPH REPAIR

Chronographs or watches with stopwatches are a complex combination of a watch and a stopwatch. Usually they are activated by pressing the crown, the chronograph hands are activated with the first press, they are stopped with the second press, and the hands are reset to zero with the third.

Modern wrist chronographs are usually equipped with two control buttons. One button controls the start and stop of the stopwatch chronograph, while the other returns the hands to the zero position.

When chronographs are repaired, they are disassembled in a specific sequence.

After removing any part, you should store it only with its screws.

When disassembling, do not touch the eccentric screws, since, having removed them from their place, it is necessary to adjust them again, which is very difficult. Chronographs are also cleaned very carefully so as not to move the eccentric screws.

In a chronograph, most of the springs are under tension, and therefore, when disassembling, you must first loosen the springs carefully.

The fine teeth of the chronograph wheels, in addition to the usual cleaning, are additionally cleaned with a glass brush until they shine.

When cleaning, pay special attention to the holes in the pin of the center wheel and in the arms.

The holes are cleaned on both sides with a wooden chock so that it goes right through.

At the end of cleaning, the holes are blown out with a rubber bulb.

Chronograph movements are assembled after the movement is assembled.

Before assembly, each part should be lightly lubricated with oil: the trunnion holes, the shoulder of the screws in contact with the levers, and the places of the springs that touch the levers.

When assembling chronographs, first install the column wheel and then replace the friction spring of the central chronograph wheel.

Carefully install the chronograph wheel on the second wheel axle, while pressing lightly on the bottom through stone.

It must be ensured that the chronograph wheel, mounted on the second wheel axle, engages correctly with the intermediate chronograph wheel and is in the same plane with it. If the wheel is fixed on the second axle too high, it must be slightly lowered down to the specified height, and if the wheel is set low, it is necessary to remove it and slightly tighten the hole in the wheel.

Next, the starting lever is assembled and its correct operation is checked, the bridge is put in place, which holds the upper trunnions of the two above-mentioned wheels. The return lever is installed, but the spring, which is in contact with the return lever, should be replaced in advance.

During installation, it is necessary to check every detail and then check the fully assembled chronograph movement.

The ease of rotation of the intermediate wheel is checked with an air stream directed from a rubber bulb to the lateral planes of the teeth. When installing the central chronograph wheel, it is recommended to check the position of the friction spring.

The tension on the spring should be such that the center chronograph wheel moves away from the wheel with which it engages, rather than approaching it. The teeth of the chronograph wheels should never be touched with a metal tool, as they can be easily damaged.

Mechanical devices for special purposes.

Chronograph "Slava"

Watch with a chain in a premium box with the emblem of the USSR

30-minute counter shifted to the left. Blued hands, lacquered dial. The accuracy of the measurement scale is 1/5 second.

Column-wheel chronograph movement, 19 jewels.
One-button control “start - stop - reset”.

Tachometer 9CHP

The specialization of the Third Moscow Watch Factory (3 MChZ) was the production of watch devices and military-purpose devices, such as bomb timers, devices for recording on-off times, etc.
This is a device for measuring the speed of a shaft (for example, an engine). When the button is pressed, it starts ticking (the sound is really very similar to a bomb) and counting the revolutions of the rotating shaft.

The rotation movement is fed to a large shaft, and is transmitted through a worm gear to a counter with an arrow. To solve the problem of the direction of rotation, an overrunning clutch is used, the same as in a modern automatic watch winding device. Whichever direction the shaft rotates, the arrow moves in one direction.

By pressing a button, an accurate measurement of the number of revolutions (taking into account incomplete fractions) is made in 5 seconds, the device extrapolates the value by a minute.

Inside is a rather complex device, something like a programmer. The program is set by the teeth on the escape wheel, some of them are omitted, actually intentionally. Control from the programmer - cam levers.

Algorithm of the device:
1.pressing the button - charging the spring
2.release the button - start balance
3.The programmer turns on, the escape wheel with missing teeth
4.Three bars of balance, the programmer stabilizes the movement of the watch device
5.On the fourth cycle, the velvet rpm measurement wheel is connected
6.The counting device measures the number of revolutions in 30 balance clock cycles (5 seconds)
7.programmer stops measurements by locking the rpm measurement wheel
8.After two more clock cycles, the programmer stops the balance

The stopwatch mechanism, like a regular watch, has a spring motor, wheel drive, travel and adjuster.In addition, the stopwatch has an additional mechanism for controlling the hands, which is called a com-pli nation.

Depending on the number of seconds hands, the nature of their action, the principle of operation of the clock mechanism, stopwatches are divided into several groups.

SOPpr - single-hand single-action stopwatch: mechanical control of the hands with interrupted operation of the clockwork.

СОПРнп-р - single-hand single-action stopwatch, mechanical control of the hands with uninterrupted operation of the clockwork.

SOSpr - one-hand totalizing stopwatch, mechanical control of the hands with interrupted operation of the clockwork.

SOSnpr - one-hand summing action stopwatch, mechanical control of the hands with uninterrupted operation of the mechanism,

SDPpr is a single-action two-hand stopwatch, mechanical control of the hands with interrupted operation of the clockwork.

SDPnpr is a single-action two-hand stopwatch, mechanical control of the hands with uninterrupted operation of the clockwork.

SDSspr is a two-hand summing action stopwatch, mechanical control of the hands with interrupted operation of the clockwork.

SDSnpr - two-hand summing stopwatch, mechanical control of the hands with uninterrupted operation of the clockwork.

The number of scales, capacity and division of second scales, scales of the counter of seconds and minutes can be different. Stopwatches are available in two calibers: 42 and 54 mm and, depending on the accuracy, are divided into three classes.

The simplest and cheapest is a one-hand stopwatch. The stopwatch mechanism has a caliber of 43 mm, an anchor stroke on eleven ruby ​​stones. The stopwatch has a second hand for counting seconds and fractions of a second, and a minute hand for counting minutes on a scale of 30 divisions. The second scale is divided into 60 large divisions, corresponding to seconds. Each major division contains five minor divisions, corresponding to 0.2 s each. The second hand moves in leaps and bounds. Each jump of the second hand corresponds to 0.2 s.

In fig. 75 shows a diagram of a stopwatch. The stopwatch works as follows. To set the stopwatch movement into motion, press the crown. The second hand will begin to move around the dial. If the crown is pressed a second time, the movement and hands will stop. Pressing the crown a third time will return the hands to the zero position.

The complication of the stopwatch mechanism is located on the platinum under the dial. In the initial position of the complication (Fig. 75, a), the arrows are set to zero and motionless. When the crown is pressed sharply, the movement through the shaft 1 is transferred to the trigger lever 15, which makes a translational movement along two guides. One of them is the cylindrical part of the screw 14, and the other is the pin 2 sliding in the groove of the platinum.

The control of the linkage system of the complication is carried out by a column wheel 12 having four columns and a ratchet wheel with twelve teeth located under it (not shown in the figure). When the ratchet wheel is turned by the trigger lever 15 by one tooth, the column wheel turns clockwise. The position of the ratchet wheel is fixed by a flat spring 10.

Spring 3 returns the trigger lever 15 to its original position. The spring 7 acts on the brake 9 of the balance 6. Therefore, when the column wheel turns, the protrusion L of the brake 9 jumps off the column 11 of the column wheel and pushes the balance of the clockwork, which was stopped by the pin 8. From this moment, the balance 6 begins to oscillate, i.e. the mechanism is set in motion. At the same time, the column 1 of the column wheel raises the double hammer 13 - the protrusion a is in the extreme right position on the column 1 (Fig. 75, b). When the double hammer is lifted, hearts 4 and 5 are released and the arrows begin to rotate.The spring 11 of the double hammer 13 always tends to turn it clockwise.

To stop the stopwatch, you need to press the crown a second time, while the lever 15 will rotate the fastening of the hearts of the ratchet wheel by one more tooth. The protrusion of the balance brake under the influence of the column 111 of the column wheel will rotate around its axis, rise to the column of the column wheel and with the pin 8 will brake the balance 6 - the mechanism will stop. When the column wheel is turned, the protrusion a of the double hammer slides over column 1 and remains in the upper position on the column.

a - the position of the stopwatch when the hands are set to zero, b - the position of the stopwatch when the mechanism is operating, c - the position of the stopwatch when the mechanism is stopped; 1 - winding shaft, 2.8 - pins, 3 - spring of the starting lever, 4, 5 - minute and second hearts, in - balance, 7 - spring, 9 - brake, 10 - flat spring, 11 - double hammer spring, 12 - column wheel, 13 - double hammer, 14 - screw, 15 - trigger, 16, 17 - springs

To return the stopwatch hands to zero (Fig. 75, c), press the crown a third time. In this case, the trigger lever will turn the ratchet wheel one more tooth, and the double hammer 13, under the action of a spring, with a protrusion a, will fall into the cavity between columns 1-11, hitting ends c and d on the minute and second cores 4 and 5. These parts have the same design. They are fixed on their axles by means of springs 16 and 17. One end of the spring enters the axle recess, and the other touches the core sleeve, tightly pulling it to the axle.

The stopwatch hands are mounted on the corresponding hubs of the hearts. When the mechanism is turned on, the axes of the hearts rotate due to the unwinding of the springs 16 and 17.

Each time the hammers strike the cores, a torque is generated that overcomes the resistance of the springs, as a result of which the arrows return to their original position.

The stopwatch balance is decelerated when the crown is pressed a second time and remains in this position until a new start, which occurs only after the hands return to zero position.

When the crown is pressed a third time, the projection b of the balance brake slides over column 111, holding the balance with pin 8.

Stopwatches such as SDS are intermittent stopwatches, in contrast to continuous stopwatches, in which the balance does not stop.

Two-hand stopwatches with two second hands have become widespread. With the help of these stopwatches, you can measure the time of any two phenomena or processes started at the same time. The SDS two-hand stopwatch is produced by the 2nd Moscow Watch Factory. The caliber of the mechanism is 54 mm. It has an anchor course, 22 ruby ​​stones are used as supports.

The second scale of dial 2 (Fig. 76) has 30 divisions: a full revolution of the second hands takes 30 seconds. Each second division is divided into 10 small divisions, corresponding to 0.1 s each. The second hands move in leaps and bounds. The jump of the second hand corresponds to one small division, or 0.1 s.

Rice. 76. General view of the SDS stopwatch:

1 - minute counter hand, 2 - dial, 3 - stopwatch start and stop button, 4 - stopwatch main hand, 5 - crown, 6 - auxiliary hand stop button, 7 - auxiliary hand

For ease of use, the second hands are made in different colors - black and red. To start both second hands, press button 3. The red (auxiliary) stopwatch hand is stopped by pressing button 6. In this case, the black (main) stopwatch hand 4 will continue to move. The black hand is stopped by pressing button 3 again. To return the black hand to its original zero position, press the crown 5.When the trigger 6 is pressed again, the red hand returns to its original position under the black second hand, regardless of where it is on the dial at that time, moving or stopped.

The SDS stopwatch allows you to summarize the readings of the second hand, that is, to start and stop it without returning to the zero position.