The invention was born because of need. For watches that rely on clockwork to run, winding has always been a hassle, so automatic winding watches and quartz watches were invented. However, for watchmakers who adhere to the field of mechanical watches, whether it is manually wound or automatically wound, long-day chain watches have always been a hot topic of continuous innovation in the watch industry. After all, the desire to motivate is always deep in the human heart, just like the roar of the engine always makes the blood flow. For watchmakers, the ideal of pursuing sufficient power certainly exists, but they must not only compromise with the reality of limited space, but also have to subordinate the watch to the principles of stability and uniformity.
Since its publication in 2007, Lange’s Lange 31 is the first and only mechanical watch with a 31-day power reserve in the past ten years. No other model has ever been better.
In 2000, Patek Philippe launched Ref.5100, a ten-day chain watch with Cal.28-20 / 220 movement. The watch industry started a competition on power storage and output. Almost every manufacturer launched seven Day and eight day chain watches. Is there a limit to power storage? When many watch fans began to think about such problems, A. Lange & Söhne launched the Lange 31 watch with a power reserve of 31 days (744 hours) in 2007. It will be the world’s longest running time on the chain. Watches, but will it also be the ultimate in the pursuit of energy storage in the watch industry?
New Lange 31 model with 18K white gold case and grey dial
Almost ten years later, Lange’s Lange 31 is still the first and only mechanical watch with a power reserve of up to 31 days, and so far no other watch can match it. The Lange 31’s patented constant-force escapement system provides uniform torque continuously. This ingenious device is located between the main barrel and the travelling wheel train, and is extremely precise. At the SIHH 2017, Lange was the first to present the Lange 31 in a new 18K white gold and grey dial design, with a limited edition of 100 pieces.
The Lange 31 is the first and only mechanical watch with a power reserve of up to 31 days. The sapphire crystal back can be seen on the L034.1 movement, as well as the special winding with screws. Winding device.
The Lange 31 is equipped with an 18K white gold case with a diameter of 45.9 mm and a delicate gray dial. At first glance, it is difficult to detect the power of a manual winding movement. Only the white number ’31’ at the top of the large power reserve indicator and the small words below the Lange large calendar display slightly reveal the clue, revealing that the watch can run for a full month after the movement is fully wound. Injecting a 744-hour power reserve into a mechanical watch is itself a major technical challenge, and it is even more difficult to ensure that the operation remains accurate from start to finish.
L034.1 bracelet movement on Lange 31
Theoretically, you can create a watch with a power reserve of 365 days, as long as your barrel is large enough and the barrel is long, strong, and powerful. However, strong power and smooth and durable power output are two different things. As Pirreli puts it: ‘Light power is like the tyrannical Feng Feng. If you can’t get the engine on the road, no matter how strong the engine is, it’s just waste.’ It is difficult to make a spring that can accommodate the driving power of the 31st day, but it is more difficult to control the power and torque output by the clockwork to achieve a precise timing curve. A. Lange & Söhne produced two overlapping 25 mm diameter barrels for Lange 31, each with a barrel of 1.85 meters long, five to ten times the length of a regular watch barrel. The power of the mainspring is enough to drive the gear for a month, but how can you control this powerful beast to make 2,678,400 seconds on the 31st, every second slip is even and smooth?
The L034.1 movement in the Lange 31 watch has a mainspring length of 1.85 meters.
A. Lange & Söhne’s solution is an ancient method known as the ‘permanent power plant’ of Remontoire. There are two keys to accurate timing of a watch. One is that the mainspring provides the power for running the wheel train and hands, and the other is that the excellent escapement can transmit and control such power smoothly and smoothly. In order to ensure that the kinetic energy transmitted from the barrel to the escapement can be kept constant at any time when the mainspring is full or the energy storage is about to run out, as early as the 15th century, the clock tower, Jobst Bürgi invented the name remontoire The ‘constant power device’ ensures that the kinetic energy transmitted from the barrel to the escapement can be kept constant at any time, whether the clockwork is full or the energy storage is about to be exhausted, to improve the accuracy of timing. Ferdinand Aldoph Lange, the ancestor of Lange, also invented his own escapement type constant power device as early as 1866. In modern times, due to the evolution of clockwork materials and production technology, this design has been gradually abandoned and forgotten because it has lost its necessity. It was not until F.P Journe published the Tourbillon Souverain tourbillon watch in 1999 that the remontoir device was used to further improve the consistency of clockwork power transmission.
The L034.1 movement on the Lange 31 shows its constant power structure and escapement.
After centuries of development, two types of remontoir devices have been developed, one is the so-called ‘train train’ permanent power plant (Train Remontoires), and the other is the ‘escapement’ permanent power plant (Escapement Remontoires) . Both are basically a spring or a blade, which is installed in the wheel train or escapement to adjust the power of the spring drum. F.P Journe’s Tourbillon Souverain tourbillon belongs to Train Remontoir. Its regulator uses a spring leaf design. It can accumulate energy from the barrel every second and then transfer the energy to the tourbillon escapement on average. DeWitt’s other Academia Tourbillon Constant Force is also the same, but its regulator is composed of a constant spring and a four-wheel inertia heavy metal located between the tourbillon cage and the third car.
The FPJ’s tourbillon lateral power unit belongs to Train Remontoire, and its constant reed is installed between the wheel trains
You can say that the L034.1 Thirty-One Day Movement built on Lange 31 is not an original invention created out of nothing, but a long-standing wisdom sublimation, but this is indeed the perfect solution that genius can conceive. A. Lange & Söhne found that the design concept of the Remontoire device can be used as a perfect buffer, adjusting the power of L034.1’s incomparable dual barrel to a smooth and continuous output. Lange’s Remontoire belongs to Escapement Remontoire in design. The uniquely designed lever, gear, an approximately triangular cam, and a clockwork on the fourth wheel constitute the main part of the permanent motion device. This constant power regulator accumulates the power from the main barrel every ten seconds, and then transfers the energy to the escapement via the constant star wheel mounted on the bearing rod. Thus, the powerful power that can run continuously for up to 31 days is tamed as a force with uniform torque and amplitude, accurately counting every second.
The Permanent Power Unit of the Lange 31 belongs to the Escapement Remontoire. The above picture shows the triangular cam, the Permanent Unit spring, and the uniquely shaped levers and gears.
Lange 31 has hours, minutes, small seconds, large date window and power storage indicator. It contains an L034.1 hand-wound movement and consists of 406 parts. It is manufactured with Lange German silver substrate, gold sleeve, blue Features such as steel screws and gooseneck trimming. To accommodate the L034.1 clockwork with a diameter of 25 mm, the case of the Lange 31 has a diameter of 46 mm and a thickness of 15.9 mm. It is the largest watch in Lange’s size (about the size of the Big Pilot watch of IWC). Although the diameter of the watch is large, Lange’s engineers carefully designed the ergonomic curvature, which is quite comfortable to wear.