IWC 76240

The 76240 is an hand-winding rattrapante chronograph movement produced by IWC based on the Valjoux 7750 from 1995 through 2004.

Details

The Valjoux 7750 movement was extremely important to the resurgence of IWC and the basic design remains in use today. The company has used it for many important innovations since the 1980's, including a perpetual calendar, rattrapante, and grande complication. The 7750 ebauche was used for the 790 family of movements and the basic architecture is the basis for today's 69000 family of movements. In 1991, IWC released an innovative rattrapante chronograph, Cal. 79030, designed by Richard Habring.

In 1995, IWC created a novel variant of the 7750 base. Cal. 76240 dispenses with the calendar and most of the chronograph functions of the 7750, leaving only the 30 minute recorder at 12:00 and adding small seconds at 6:00 instead of the usual placement at 9:00. This modification was anything but simple, however. Relocating the running seconds required cutting away part of the movement base plate and adding an all-new bridge with three wheels and a tension spring. Removing the calendar plate required the creation of a new plate to cover the gear train. Next, Habring's rattrapante design was added. A final modification was the removal of the automatic winding mechanism in favor of a simple hand-winding works.

This movement powered the Porgugieser Chrono-Rattrapante, Ref. 3712. It was produced from 1995 through 2004.

Applications

• IWC Porgugieser Chrono-Rattrapante 3712 (1995-2004)

Description: Hand-winding chronograph rattrapante movement based on Valjoux 7750 Functions: Hours, minutes Rattrapante chronograph seconds operated by pusher at 10:00 Small seconds at 6:00 Chronograph minutes at 12:00 Data: Ø 30 mm 31 jewels 21,600 A/h Power reserve 44 hours Production period: 1995-2004