A. Lange & Söhne / Zeitwerk Part.2

When it was first released, the Zeitwerk was heavily criticized, with some saying it was "not at all like A. Lange & Söhne." However, this watch, with its instantaneous digital display, quickly captured the hearts of enthusiasts with its unique aesthetic and high practicality. In fact, this watch has a design rooted in classics. Its strong torque eventually became a catalyst for encouraging A. Lange & Söhne to incorporate more functions. In this article, we will look back at its unique origins and history.

Making full use of the abundant torque
Development into a chiming watch

Although the Zeitwerk collection is primarily a mechanical digital watch, a mechanism that is not particularly versatile, since 2011 the collection has continued to evolve into chiming watches, made possible by powerful torque and more efficient mechanisms.

　The remontoire gave the Zeitwerk an instantaneous digital display. However, the remontoire, which "wastes" the torque of the mainspring, is not a highly efficient mechanism to begin with. In addition, the Zeitwerk's heavy digital display affected the watch's performance even with the addition of the remontoire. In theory, with the remontoire, the balance's oscillation angle should be stable even when the hour and minute change and torque is consumed. However, as mentioned above, the Zeitwerk's oscillation angle drops by up to 30 degrees.

　Considering the heavy disks that must be moved, a 30-degree swing-back is actually quite good. However, it is typical of A. Lange & Söhne that they were not satisfied with that. The company's engineers did not just want to "move the Zeitwerk lightly," but also wanted to use the excess torque to move additional mechanisms.

　The first attempt was the "Zeitwerk Striking Time" in 2011. This was a simple sonnerie that chimed every hour and at the 15, 30, and 45 minutes. Tino Beauve, who designed it, said, "The idea of ​​adding a chiming mechanism to a watch came from restoring a Grand Complication. Fortunately, the Zeitwerk's mainspring had a torque of 2700g, so adding a mechanism that chimed every 15 minutes was no problem." Incidentally, the idea of ​​adding even more functions was originally proposed by Günter Blümlein, who revived the company. The Zeitwerk, with its immense torque that Tino Beauve describes as "more than a Lange 31," was the perfect fit for implementing "Blümlein's method of adding something to something."

　Initially, A. Lange & Söhne focused solely on the Zeitwerk's powerful torque. Even if they were to tamper with its internals, the Zeitwerk's mechanism was too intricate to be easily tampered with. However, with the 2015 Zeitwerk Minute Repeater, the design underwent a major evolution. This meant that the efficiency of the entire mechanism, including the remontoire, was improved. As evidence of this, the torque of the mainspring was reduced by 300g from 2700g for the striking timepiece.

　The Zeitwerk Minute Repeater was designed by a team led by Anthony de Haas. "In a typical repeater, the mainspring, which powers the repeater, is charged by moving a slider on the side of the case. This generates a large torque, but the large opening makes it difficult to make the watch waterproof. On the other hand, a push-button watch would be more waterproof. It's true that a push-button watch doesn't have enough stroke to charge the mainspring for the repeater. But the Zeitwerk has a mainspring with ample torque, so that excess power can be used to power the repeater."

The Zeitwerk Striking Time mechanism is extremely compact.

Overall view of the Zeitwerk Minute Repeater. While it looks similar to the Striking Time, the internals are completely different. The gear train for the repeater runs from the barrel through the 9 o'clock position to the 6 o'clock position. The protrusions on the outer circumference of the ring act as a snail cam, and a rack that reflects the movement of the snail cam is placed on top of it at the 6 o'clock position on the dial side.

　The idea of ​​using the excess energy from moving the hour and minute displays to produce a sound is exactly the same as with striking timepieces. However, when it comes to repeaters, the design suddenly becomes more difficult. Striking timepieces only sound once on the hour, at 15 minutes, 30 minutes, and 45 minutes. In contrast, a minute repeater needs to sound as many times as the number of hours and minutes. The torque required to produce the sound must be much stronger than that of striking timepieces, and more space is required to house the mechanism. It would be impossible to install one without improving the efficiency of the mechanism itself.

　De Haas and his team first considered how the sound would be played: whereas a typical repeater would sound every hour, quarter hour, and minute, his team came up with the idea of ​​having it sound every hour, ten minutes, and minute.

"The Zeitwerk has a disc that changes every 10 minutes. I wanted to synchronize the repeater with that movement," he says. As a result, this repeater is a very unusual "decimal repeater" that sounds in decimal notation. He explains that this is also because the sound of the repeater synchronizes with the time you see.

The gongs and hammers of the Zeitwerk Striking Time. The gong on the left is a low-pitched gong that strikes every hour on the hour. The gong on the right is a high-pitched gong that strikes every quarter hour. According to A. Lange & Söhne, "It is designed to produce the same sound as the opening of Beethoven's Symphony No. 15, 'Fate'."

The L043.5, which uses a single barrel to power the gear train, digital display, and repeater, incorporates various safety mechanisms: if the power reserve falls below 12 hours, the button locks to prevent the repeater from ringing.

　The number of times each tone is sounded is determined by a snail cam that engages with a "rack" and reads its movement. This repeater is equipped with three snail cams: one for the hours, one for the ten minutes, and one for the minutes. The clever thing about this repeater is the location of the snail cams. In a typical repeater, the minute wheel rotates the snail cam, but in this repeater, the cam that moves every ten minutes is fixed to the axis of the ten-minute display disc. This significantly reduces the space required. Let's say the display on the ten-minute disc changes from 1 to 2. The cam attached to the axis moves one step, and the rack that engages with it reads the cam's movement, moves the gong that distance, and sounds a chime. While the disc with the snail cam is heavier, the Zeitwerk's strong torque and efficient mechanism overcome this problem.

　The cams that read the hours and minutes are not the axis of the discs, but they engage with the respective discs that display these, reading their movement and reflecting it in the rack. The design of the Zeitwerk Minute Repeater was practically complete when the idea of ​​linking the cams to the hour, ten-minute, and minute display discs was conceived.

　In addition to its powerful torque, the Zeitwerk's energy-saving mechanism made it possible to realize a minute repeater. The enormous energy required to realize an instantaneous digital display eventually led to the creation of a wide variety of variations of this model.

ZEITWERK STRIKING TIME
The origin of the simplest chiming clock

　The Zeitwerk Striking Time, released in 2011, is a simple sonnerie. It is not as complex as a minute repeater, which strikes multiple times, and its mechanism is not as sophisticated as the Decimal Strike, which is also a simple sonnerie but strikes every 10 minutes.

　However, it was undoubtedly with this model that A. Lange & Söhne accelerated the development of multi-functionality, and in terms of expanding the possibilities of the remontoire that the Zeitwerk presented, this model can be said to be one of the milestones that the company has built up. Without the success of the Zeitwerk Striking Time, it is unlikely that the company would have considered using the remontoire to evolve complicated watches.

　To be honest, like other Zeitwerk striking watches, the volume is not particularly loud. However, it's sufficient as a reminder, and this model, which chimes every 15 minutes, seems more user-friendly than the Decimal Strike, which chimes every 10 minutes. Also, while the mechanism remains the same, the finish of the case and dial has clearly improved compared to previous models. The appeal of A. Lange & Söhne is no longer limited to unique mechanisms, German silver bridges, and plates.

　Since its release in 2009, the Zeitwerk has been attracting attention for its unique mechanism. However, its large, instantaneous digital display is not only highly legible, but also easy to use. The addition of sound emphasizes its practicality, making it an appealing watch for mechanical watch fans as well as those looking for a practical luxury watch. Taking its inspiration from a 19th-century digital pocket watch, A. Lange & Söhne has reworked it into a modern, practical wristwatch. This was made possible by the company's "never stand still" attitude.