To celebrate the 85th birthday of Philippe Stern, historical President of Patek Philippe from 1993 to 2009 and current Honorary President, Thierry Stern (representative of the fourth generation of the Stern family, and appointed President in 2009) has decided to pay tribute to his father by producing a special series of thirty watches housing a brand new movement, developed exclusively for this timepiece, and which will never be used again. The watch, with its 41 mm platinum case, is distinguished by its Officier-style case and black Grand Feu enamel dial, on which Philippe Stern's portrait, painted in miniature on white and grey enamel, stands out.
Since its founding (in 1839), the Patek Philippe Manufacture has established a reputation for virtuosity in the field of chiming watches, both on passage (grande sonnerie, petite sonnerie) and on demand (repeater). In 1989, on the occasion of the 150th anniversary of the company's founding, Philippe Stern (who was Director at the time) marked the grand return of the minute repeater in a Patek Philippe wristwatch with the launch of the self-winding Calibre R 27, the first movement of its kind to be entirely designed and manufactured in-house. Over the years, the minute repeater regained a prominent place in Patek Philippe's offer, to the point of constituting today the most extensive collection of minute repeater wristwatches in current production, with some twelve timepieces offering this Grande Complication, alone or combined with other functions (grande sonnerie, petite sonnerie, tourbillon, perpetual calendar, chronograph, universal time, etc.).
The development of the new self-winding Calibre R AL 27 PS forced Patek Philippe's engineers to completely rethink the minute repeater mechanism to accommodate the alarm system. The challenge was to create a watch that would play the minute repeater and alarm on the same two classic gongs, while retaining the slide system housed in the left side of the case, the visual signature of Patek Philippe's minute repeater watches. To achieve this, the movement had to be capable, after the activation of the cursor, both of instantly striking the time displayed on the dial (in minute repeater mode) and of putting the chime on hold until the time displayed matched the preset time (in alarm mode).
Unlike classic minute repeater watches, in which winding through the slide instantaneously engages the striking mechanism, the addition of an alarm system meant that the striking barrel had to be able to be disengaged by the striking mechanism of the chime components (quarter component, minute component, hour finger).
Because of these technical constraints, it was necessary to add 227 components, including a bascule and column wheel system for selecting the striking mode, and a striking mechanism used to temporarily disconnect the energy source (the striking barrel drum) from the striking mechanism, a system usually reserved for watches equipped with large bells. The development of the R AL 27 PS calibre has resulted in the filing of four new patents for mechanisms that allow, in particular, safe switching from one striking mode to another, putting the alarm chime on hold until the appropriate moment, while ensuring the correct sequence of strokes "hours, quarters and minutes". And at the same time ensuring that the striking barrel is always fully charged each time the slide is activated, so that the watch can always strike up to 31 strokes for the alarm (12 o'clock and 58 minutes) if necessary.
The watch, which goes by the name of Minute Repeater Alarm Ref. 1938P-001, has a sapphire crystal case back protected by a hand-engraved 'cuvette' bearing the inscription 'À mon père, 85 ans de passion horlogère' (To my father, 85 years of watchmaking passion). Through the sapphire crystal, one can admire the meticulous finishing of the new R AL 27 PS calibre, in particular the bridges and hammers with gold-plated angles, as well as the 22-carat yellow gold rhodium-plated micro-rotor with black lacquered hand-engraving, which reproduces Philippe Stern's signature.
