Valjoux

ETA/Valjoux 7750. (photo 2009)

Chart of historic Valjoux movements

Valjoux (for Vallée de Joux, "Joux Valley") is a Swiss manufacturer of mechanical watch movements. It is known primarily for chronograph ébauche movements that are used in a number of mid- to high-range mechanical watches: The company has been a part of ETA for a number of years and is a member of the Swatch Group.

Valjoux 7750

Valjoux is responsible for the design and manufacture of the Valjoux 7750 movement (and variants), an extremely popular movement used in the majority of mechanical chronograph watches on the market today.

The Valjoux 7750 is different from most other chronograph movements because it uses the three-plane cam system rather than the column wheel. It is constructed of a mainplate, calendar plate, and chronograph top plate. Levers push a cam back and forth, driving the stopwatch mechanism of the Valjoux 7750. This is referred to as a coulisse-lever escapement. In the 1980s, many companies began using the Valjoux 7750 during this time because it was easier to mass-produce and distribute in high-volume, thanks to its cam system construction. The Valjoux 7750 can be created in several different displays, including adding or eliminating a date window or adding or subtracting a subdial. Watch companies can purchase the movement and alter it in house if they desire.

Some watch brands that use base movements manufactured by Valjoux include Appella, Breitling, Cyma Watches, Fortis, Gallet, Glycine, Hamilton Watch, IWC, Junghans, Longines, Mido, NIXON Inc., Omega, Oris, Panerai, Porsche Design, Sinn, TAG Heuer and Zodiac.

There are also a large number of derivative chronograph movements based on the Valjoux 7750 base. These include ETA's own Valgranges, designed for larger watches, as well as the following third-party movements:

• Alfred Rochat for Chronoswiss (C. 732 or C. 741, C 741 by Rochat)
• Fortis (developed by Paul Gerber featuring an alarm and two springs)
• Franck Müller (for example FM 7850 CC MB)
• IWC
• Jacques Etoile (cal. IV.C4)
• La Joux-Perret/Jacquet (for Jaquet Droz, Bremont BE-83, and others)
• Paul Picot ("Atelier Technikum")
• Panerai
• Porsche Design (Eterna 6036)
• Revue-Thommen ("Airspeed Flyback")
• Sinn ("Flyback")
• Soprod
• Damasko (fitting a Si main spring to the 7750)

Further reading

• Odets, Walt, "The Valjoux 7750 chronograph", timezone.com.
• Braun, Peter; Mook, Andreas, "Special: Caliber Corner Chronographs: The Valjoux Engine"

External links

• Valjoux Reference Site Excellent source for company history, watch details, etc.
• "Valjoux Watch Movements", ofrei.com, Otto Frei
• Alliance Horlogere A page containing information about the Valjoux 7750 along with a video showing the mechanism being assembled
• [1] Crown & Caliber