In-Depth, 1815 "Homage to Walter Lange" steel - Jumping seconds according to A. Lange & Söhne

Geneva - “The Geneva Watch Auction: SEVEN”, a prestigious watch auction organized by Phillips in association with Bacs & Russo, has just ended. Among the numerous timepieces that have been sold out over the course of this weekend, the unique piece created by A. Lange & Söhne: the 1815 “Homage to Walter Lange” in steel has met with great interest. 

This unique and coveted timepiece with independent central jumping seconds and dial grand feu in black enamel, it has captured the attention of collectors and enthusiasts as expected. The final sale price was in fact around CHF 852,500 € 715 thousand.

A few months ago in anticipating the mass atauction of 1815 "Homage to Walter Lange", we have revealed some technical details. Today we want to talk to you in more detail about the technical solutions that are 'hidden' within this authentic masterpiece not only of elegance, but also and above all of micro-mechanics.

Il 1815 "Homage to Walter Lange", developed to commemorate its founder one year after his death, is based on a historical patent owned by Lange: the independent second deaths, considered precursors of modern chronographs.

The technical solutions adopted in 1815 "Homage to Walter Lange" can be summarized as follows:

- the train of wheels for the jumping seconds is located above the platen ¾
- the jumping seconds are controlled by a "flirt-star" mechanism 
- the solution adopted makes it possible to activate or stop the jumping seconds without interfering with the running of the movement.

THE ROTISM OF THE SECONDS SITUATED ABOVE i ¾ by Platina

The complication of jumping seconds is a real tradition for A. Lange & Söhne.
The first pocket watch capable of housing this fascinating watchmaking complication is attributed around 1867 to Ferdinand Adolph Lange. In the early design stages, he placed the seconds mechanism in the platen. Ten years later, Richard and Emil Lange patented a solution capable of positioning the second wheel train over the ¾ of the platen. The advantage of this configuration allowed the watchmaker to remove the seconds mechanism without having to intervene on the entire movement.

Therefore, also for the first Lange pocket watch, in addition to the small seconds, we find the jumping seconds indicated by a large hand that marks the minutes in precisely 60 seconds. The hand could be operated or stopped by pressing a button. As with a chronograph, the entire process is controlled with the help of a column wheel. Also in 1815 "Homage to Walter Lange" the jumping seconds mechanism, visible thanks to the visible caseback above the three-quarters of the plate, operates according to the principles described in patent No. 182 dated 1877.

CONTROL OF THE SECOND LEAPS

As in the historic mechanism, a 'flirt' lever (1) and a star (2) are the elements that control the jumping second hand, converting six semi-oscillations of the balance wheel into one 'click' of the hand per second.
Together with the escape wheel (3), the five-pointed star (2) - located above the wheel axis via a transparent ruby ​​- completes one rotation on its axis once every five seconds. After every second, a point of the star releases tension from the lever. The star will rotate 360 ​​° before being stopped by the next tip. This rotation is transmitted to the central seconds hand via the wheel train, allowing it to advance to the next seconds scale notch.

START / STOP MECHANISM OF THE SECOND JUMPERS

If the button is pressed while the central second hand is moving, the V-shaped lever in contact with the column wheel blocks the flirt along with the entire second wheel train, while the movement wheels continue to move smoothly.
The contact between the movement and the second wheel train takes place via a "click" system. The ratchet wheel (8) is in close contact with the wheel train; with two clicks (6) (9) and their spring, it transfers the energy to the click wheel (7). The levers of the mechanism make contact with the ratchet wheel (8), allowing the force to be transferred from the barrel (4) to the seconds mechanism.

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