Watches essentially tell time by the integration of three main components: an energy source, a time regulating mechanism and a display. The energy source can be electronic (as in a battery) or mechanical (as in a wound spring). A watch’s main timekeeping mechanism is called its movement. Today’s watches fall into two categories: Mechanical movements and Quartz movements. Here’s a breakdown of how each type of movement works:
Automatic:
Mechanical watches are made up of about 130 parts that work together to tell time. Automatic mechanical movements mark the passage of time by a series of gear mechanisms, and are wound by the movement of your wrist as you wear it. The gear train then transmits the power to the escapement, which distributes the impulses, turning the balance wheel.
The balance wheel is the time regulating organ of a mechanical watch, which vibrates on a spiral hairspring. Lengthening or shortening the balance spring makes the balance wheel go faster or slower to advance or retard the watch. The travel of the balance wheel from one extreme to the other and back again is called oscillation. A series of gears, called the motion work, and then turns the hands on the watch face, or dial.
Quartz:
Quartz watches work with a series of electronic components, all fitting together in a tiny space. Rather than a wound spring, a quartz watch relies on a battery for its energy. The battery sends electrical energy to a rotor to produce an electrical current. The current passes through a magnetic coil to a quartz crystal, which vibrates at a very high frequency (32,768 times a second), providing highly accurate timekeeping. These impulses are passed through a stepping motor that turns the electrical energy into the mechanical energy needed to turn the gear train. The gear train turns the motion work, which actually moves the hands on the watch dial.
Mechanical:
A mechanical watch uses the energy from a wound spring, and keeps time through the highly regulated release of that energy through the wheel train and an escapement. It differs from the typical quartz watch in that it uses purely mechanical components to keep time. Mechanical watches typically can run for about 36 hours on one full winding of the mainspring, with a few designs available with up to 10 days, of power reserve.
The basic design of mechanical watches has not changed very much in the past fifty years but what has changed is the use of light weight materials in the design and manufacture of movements.
Manual:
A mechanical movement in which winding is performed by hand. The motion transmitted from the user’s fingers to the crown is forwarded to the movement through the winding stem, from this to the barrel through a series of gears and finally to the mainspring.
GMT:
Abbreviation for Greenwich Mean Time. A feature that displays two or more time zones. In this case, the second time may be read from a hand making a full rotation in a 24-hour ring.
Tachometer:
Function measuring the speed at which the wearer runs over a given distance. The tachometer scale is calibrated to show the speed of a moving object, such as a vehicle, over a known distance. The standard length on which the calibration is based is always shown on the dial.
Perpetual Calendar:
A perpetual calendar is the most developed form of the simple date window on a typical watch. It keeps track of date, day-of-the-week, months, year, leap years, and rarely centuries. Because of the relatively complex rules governing the Gregorian calendar, including the varying lengths of months, and leap years every four years, a typical perpetual calendar has wheels turning from several times per second (balance wheel) all the way to once every four years.
Moon-phase calendar:
A complication which displays the evolution of the moon.
Annual calendar:
A watch displaying the day, date, month that adjusts automatically for short and long months. An annual calendar requires only a single manual correction per year from the end of February to the 1st of March.
Some less complex calendars are also available:
- Semi-perpetual calendars.
- Annual calendars.
- "Triple date" calendars, which contain month, day, and date - but need to be manually advanced at the end of each (short) month.
World Time:
Additional feature of watches provided with a GMT function displaying the 24 time zones on the dial or bezel. Each zone is referenced by a city name which providing instantaneous reading of the time of any country.
Digital:
Said of watches whose indications are displayed mostly inside an aperture or window (s.) on the dial.
Power reserve:
Duration in minutes or hours of the energy stored inside an automatic movement after it has reached the winding peak. The duration value is displayed by an analog indicator.
Accutron:
The Accutron is movement driven electronically and developed in the early 1960's by the Bulova Corporation. Instead of having a mechanical balance wheel, the Accutron used a mechanically resonating system to keep a constant vibration rate for the rest of the mechanical movement.
The Accutron movement creates a distinctive audible hum when operating, and their second hand is driven at such a high frequency that it appears to move continuously like an automatic. The Accutron was the first major advance using electronics in timekeeping. Because of this advance, Accutron was used by NASA and is cherished by many collectors.
Regulator:
Regulating the functioning of a movement by lengthening and shortening the active section of the balance spring. It is positioned on the balance-bridge and encompasses the balance spring with its two pins near its fixing point on the bridge itself. By shifting the index, the pins also are moved and the portion of the balance spring capable of bringing the balance back is lengthened or shortened by its elastic force. The shorter it is, the more reactive it tends to be and the more rapidly it brings the balance back and makes the movement run faster. The contrary happens when the active portion of the balance spring is lengthened. Given today’s high frequencies of functioning, even slight index shifts entail daily variations of minutes.
Chronograph:
Is a device that measures elapsed time With a second hand independent of the watch's timekeeping. The chronograph rotates one revolution a minute, can be started, stopped, and returned to zero by buttons on the case. A chronograph can also be used to display total elapsed time from minutes into hours, and even days.
Chronometer:
With the advances in watch manufacturing all watches are chronometers but to be C.O.S.C certified they must qualify as chronometers and meet the ISO 3159 standard set by the Swiss Official Chronometer Control (C.O.S.C.).
Contrôle Officiel Suisse des Chronomètres (C.O.S.C.) - the most important Swiss institution responsible for the functioning and precision tests of movements of chronometers . Tests are performed on each individual watch at different temperatures and in different positions before a functioning bulletin and a chronometer certificate are issued, for which a maximum gap of -4/+4 seconds per day is tolerated.
Tourbillon:
A tourbillon was created by watchmaker Abraham Louis Breguet to create the absolute best accuracy in automatic wristwatches. This meant balancing out the effects of gravity while the watch is on the wrist and in various positions caused by arm movement. The solution he devised placed the balance wheel, escape lever, and escape wheel in a cage, which then rotated as a unit within the movement as a result of the normal escapement process. In this way, the overall effects of gravity get balanced out, as the escapement of the movement never spends any significant time in one vertical position.
However, this solution is very complex, with the result that a tourbillon has become more a statement about the watchmaker's skill rather than having any real performance advantage - starting price on a tourbillon is roughly in the $50,000-$200,000 range.
Repeater:
A Repeater, or "Repetition Minutes" is a variety of chiming watch. Unlike a striking clock, repeaters do not automatically strike the hour, quarter, or minutes in passing - they must be activated by the user, usually through a slide or push button.
Repeaters currently come in several varieties, based on the smallest unit of time which they can indicate:
- Quarter Repeater:
Chimes the hour, followed by the number of quarter-hour intervals at the current time. (example: 2:21 = two chimes for the hours and 1 chime for passing the first quarter-hour.)
- Half-quarter Repeater:
Chimes the hour, followed by the number of half-quarter hours (i.e. 7.5 minute intervals) past the hour. (example: 2:21 = two chimes for the hours, then two chimes for two half quarters and chime three times passing 2:22:30)
- Five-minute Repeater:
Chimes the hour, followed by the number of five-minute intervals (example: 2:21 = two chimes for the hours, then four chimes for passing 20 minutes past the hour.)
- Minute Repeaters:
Chimes the hour, followed by quarter-hours, followed by minutes (example: 2:21 = two chimes for hours, 1 chime for passing the first quarter-hour, and six chimes for minutes into the second quarter hour.)
All self-winding watches work on the principle of converting arm motion into the winding of the mainspring. Usually, this is performed by a half-disc of metal weighted at the edge called a rotor, which spins when the wearer's arm is accelerated unpredictably (that is, when moved normally in the course of everyday life). This rotary motion is then geared down to wind the central arbor of the mainspring.
All automatic watches have an overwind protection mechanism of one sort or another, to prevent breaking the mainspring once fully wound. In a typical system, the mainspring, which is wound at the central arbor of the barrel, is not rigidly attached to the outside of the barrel. Instead, there are a series of detents along the outer edge of the barrel that allow a stiffly constructed mainspring part called the bridle to slide along when an attempt to overwind is made. On some watches, a faint click can be heard when this happens, on others, it cannot be heard. It should be noted that this overwind protection is critical to avoid damage to the watch, and is reported to be one of the more tricky things to get right during a watch service because of the special lubricant needed to ensure proper operation.
What is a complication:
A complication is defined as a wristwatch function beyond that required for simple hour, minute, and second. More practically, common additions such as a day/date window are typically excluded from this definition. This leaves a wide variety of features that can be either commonly or less frequently found on watches.
Mechanical Watch Maintenance:
It is very important to periodically service a watch to ensure that the components are well-lubricated, and that the mechanism is free from debris and moisture. Any amount of moisture inside a mechanical watch will wreak havoc with the anchor escapement and escape wheel.
What is a Watch Winder:
The Theory behind a Watch Winder is to strap an automatic watch to a motorized pillow, which moves the watch enough to keep it wound when it is not worn. Now you can choose to wear any watch at any time and not have to reset the time or calendar.
Manufacturers made their winders mechanically foolproof to avoid damaging watches by using an electrical timing unit, created a motor to switch directions and also built them to look like a jewelry box.
Mechanical vs Quartz:
A quartz watch is cheaper and more accurate than a mechanical watch but a crafted mechanical watch can typically be made no more accurate than 2 seconds per day. A typical quartz watch is usually good to 0.5 seconds per day.
But mechanical watches are not about achieving the ultimate in accuracy. Craftsmanship, aesthetics, and tradition are all part of the allure. Because the wheel train of an analog quartz watch is not under constant stress from a wound mainspring, it does not need to be as finely finished, nor does it require painstaking skill and precision in assembly.
Manual vs. Automatic:
An "automatic" wristwatch is a mechanical wristwatch with a self-winding mechanism. In other words, one does not have to wind the crown periodically to keep the watch running. A "manual" or "manual wind" watch must be wound by hand, using the crown, usually every day, to operate continuously.
If one were going to own only a single watch, and wear it every day, an automatic would be a good choice, since the watch will be worn consistently enough to stay wound - the owner would never need to manually wind the watch, and would only need to adjust the time to compensate for drift and at changeover to daylight/summer time and back.
For this reason, most commonly seen watches with more than a simple date window use automatic movements - this includes "triple date" calendars, annual calendars, perpetual calendars, and any of these combined with a Moonphase. With few exceptions (oddly enough, these seem to be more expensive watches), most manual wind watches have simpler calendars; although they may include other complications like chronographs.
Finally, since frequently worn automatics are usually at or near a full state of wind most of the time, one may get the impression that they can be adjusted to be more accurate and consistent over the course of many days. This, in fact, is not necessarily the case, as a manual-wind watch that is wound consistently once per day can be tweaked so that the day to day variation is very small. In short, there is no definite performance advantage to an automatic - it is mostly a convenience.
Kinetic vs. Autoquartz:
The Seiko Kinetic and ETA Autoquartz movements are quartz movements. However, they use a rotor system similar to those used by automatics. The difference is that the rotor's motion is converted to electricity, which is then used to charge a capacitor. The quartz movement then draws current from the capacitor as if it were a battery.
It should be noted that the latest generation of autoquartz movements can store enough power to run the watch for several months (or even years in the case of the Seiko Auto-Relay); a mechanical automatic can only store as much power as contained in the mainspring - which is usually only 40 hours or so for most automatics.
Please note:
Water resistant watches are now part of everyday life. Most people assume that they have been part of our life style for endless years but water resistant watches were not possible until the 1940’s. Up until that time, the manufacture of watch cases did not allow for this important feature. Wearers restricted their use of a watch whenever there was a chance it would get wet. The vast majority of watches in use in the 40’s, 50’s and 60’s were not water resistant, shock resistant or anti-magnetic. It is only in recent years that the life style of most people includes activities involving contact with water or extremities.
Proper maintenance of a water resistant watch case is not a commonly known fact. The various watch manufacturers do their best to explain the need for water testing and resealing this type of watch. Despite this, many watch wearers are unaware of the need of routine maintenance.
Never operate the crown or push buttons in the water or while the watch is wet.
Never wear your watch in a “hot tub." Watches are not designed for this type of exposure to the extremes of hot water against the body of the case. The watch can withstand the “dry heat” of a desert, but not direct contact with the extremely hot water used in a hot tub.
Any sign of condensation on the inside of the crystal is an indication of a possible leak. Have the watch inspected and repaired immediately.
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