Automatic winding (also self-winding called) uses the physical movement of a watch (usually rotation) to turn the barrel and wind the mainspring. It differs from the traditional manual winding, also called "manual" or "keyless" winding.
With this type of winding, a rotating oscillating weight (rotor), which is moved by the movements of the watch on the wrist of its wearer, causes the automatic winding of the watch movement. the most common design principle is that of the central rotor, an alternative to which is the principle of the micro rotor or the rotor of the main rotor. Planetary rotors. There are unilaterally and bilaterally winding oscillating weights.
Abraham-louis perrelet is considered the inventor of the automatic winding system for pocket watches. In the 20s of the 20. at the beginning of the twentieth century, when the wristwatch was preparing to conquer the world, the englishman john harwood invented the automatic winding system for wristwatches. Only now did this type of winding really make sense, since arm movements trigger the required plus of kinetic energy, which is necessary and useful for this type of drive.
The real, mass-produced start of the automatic wristwatch, however, can only be dated to the year 1931, when rolex introduced the "perpetual" winding mechanism, which made manual winding completely unnecessary. Over the next 40 years, almost every watch manufacturer introduced its own automatic winding mechanism, which is the predominant system today.
Albert pellaton developed another system of automatic winding, which was patented in 1946 and completed in 1950 as the pellaton winding system.
Another version of the automatic winding system is the "pump-action" automatic-automatic from wyler dar. But this solution could not prevail.
Before watches with automatic winding were worn in space, there were brief discussions about whether enough kinetic energy could be developed there due to the lack of gravity. The first space watch, the omega speedmaster professional ("moon watch"), was still a manually wound watch. Finally, however, the first fortis models worn by russian cosmonauts in space, official cosmonauts chronographs with automatic winding, showed beyond doubt that even the simple movements of the body, common in everyday life, were quite sufficient to supply the watches with the energy they needed.
Exploded view of the bidynator movement
many early automatic winding systems did not rotate freely through 360 degrees. instead, the weight segment rotated a shorter distance before reaching a spring and a stop at each end. these so-called "bumper" or "hammer" winding systems were functional, but created a strange sensation on the wrist. Although they were produced on a large scale in the 1950s, they quickly fell out of fashion and were replaced by free-spinning winding mechanisms after the patents expired. In the late 1960s, hammer automatics were no longer produced.
in 1942, the raw materials manufacturer felsa introduced the "bidynator", the first two-sided (bi-directional) winding mechanism. Finally, eterna eliminated various rotor bearing problems by using a miniature ball bearing starting in 1948, and shortly thereafter adopted bidirectional winding. Seiko developed a completely different method of bidirectional winding in 1959 with the "magic lever" system.
Today, most self-winding watches have a two-sided winding mechanism, although the one-sided (unidirectional) winding mechanism is still quite common. The current trend is back to unidirectional winding on the grounds that it is more efficient and reliable. Most of these watches are wound clockwise, but many are also wound counterclockwise, which poses a problem for users of electronic watch winders.
the competition between the developers of the breitling/heuer caliber 11 (with microrotor), also called chronomatic, and the el primero from zenith/movado (with central rotor) marked the beginning of automatic winding in chronographs in 1969. seiko also delivered its 6139 automatic chronograph in 1969, and in 1973 and 1973, respectively. followed in 1974 by the lemania 5100 and the widely used valjoux 7750.
Automatic movements with manual winding
Many automatic movements can also be wound by hand. However, it is debatable whether this can damage the mechanism and clutches of the keyless movement and should be avoided in certain movements, such as the popular ETA 2824-2.
automatic movement zenith el primero with central rotor
In the most common automatic winding technique, the weight segment is placed on a pivot in the center of the movement. The segment then rotates around the outer edge of the movement. this usually requires a free space around the top of the movement for a freely rotating segment, although a hammer central rotor automatic is also possible.
central rotors were a challenge for alarm watches like the jaeger-lecoultre memovox. The earliest models use a hammer to let the alarm hammer through, while later movements use a central hammer in a wider than normal rotor pin.
some manufacturers (notably citizen and patek philippe) have produced wheel movements with peripheral winding. These do not have a central pivot, but attach the weight segment to a ring that rotates around the outside of the movement. These proved to be problematic and were abandoned in favor of central or micro rotors.
movement universal 100 with microrotor
Although most automatic winding mechanisms use a weight segment along the entire circumference of the movement, there are also some that use a smaller insert rotor or "micro rotor". This concept has been used since the invention of the automatic elevator and is still used to a limited extent today. microrotors are often used in ultra-thin movements or where a full rotor would interfere with other complications.