ETA/Valjoux 7750 (photo 2009)Chart of historic Valjoux movements
Valjoux (for Vallée de Joux, "Joux Valley") is a Swiss manufacturer of mechanical watchmovements. It is known primarily for chronographébauche movements that are used in a number of mid- to high-range mechanical watches. The company is a part of ETA, and is a member of the Swatch Group. They are also the movement providers for early Rolex Daytonas such as 6263.
Valjoux is responsible for the design and manufacture of the Valjoux 7750 movement (and variants), an extremely popular movement used in many mechanicalchronograph watches.[1]
The Valjoux 7750 is different from most other chronograph movements, using 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 because it was easier to mass-produce and distribute in high volume. 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.
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)
Dreyfuss & Co. (Have a range of 7750 Valjoux watches)
Fortis (developed by Paul Gerber, featuring an alarm and two springs)
