Patek Philippe Tourbillon Minute Repeater Perpetual Calendar 5207 (5207/700P-001)

The watch pays tribute to the Ref. 3969 with a jumping digital hour which was launched in 1989 on the occasion of Patek Philippe's 150th anniversary. It also illustrates how much the manufacture's technical prowess and expertise have progressed during the past 25 years.
A closer look at the Chiming Jump Hour reveals that the seconds hand jumps from one scale marker to the next in one-second steps. As soon as the seconds hand reaches the 60, the minute hand also jumps from one minute marker to the next. And finally, once an hour, the digital display in the aperture at 12 o'clock jumps to the new hour precisely at the same moment when the seconds and minute hands advance. A soft tone can be heard at this moment: the Chiming Jump Hour indicates the top of each hour acoustically as well.

Jumping time indications are complications characterized by a high level of mechanical complexity. In conventional mechanical watches, the hands move continuously in step with the balance. In most watches, it beats at 6 or 8 oscillations per second. With every semi-oscillation, the balance allows the escape wheel to rotate by one tooth, and this motion is transferred to the hands by the going train. The hands move forward incrementally. The seconds hand makes this cadence apparent, but the stepwise motion of the minute and hour hands is barely discernible.

The Chiming Jump Hour also has a balance, and it performs 8 semi-oscillations per second. However, the energy is not directly transferred to the seconds hand. Instead, it is accumulated in a storage mechanism that only releases it to the fourth wheel when the eighth semi-oscillation takes place. Analogously, the power stored during a time interval of 60 seconds must be delivered to the minute hand instantaneously, and the same process occurs after 60 minutes when the digital hour display needs to be advanced as well.

The watch houses the new manually wound caliber 32-650 HGS PS movement. During a period of four years, the in-house ateliers developed mechanisms that could not only store the energy needed for the jumping indications but would also synchronize the jumps of the seconds, minutes, and hours with extreme accuracy. Three patent applications were filed for these solutions. The most conspicuous part is the seconds lever made of Silinvar®, a derivative of silicon. It is connected to a spring which stores the energy of the eight semi-oscillations of the balance that make up one second. With a beak, the lever engages with a wolf-tooth Silinvar® wheel which in turn meshes with the fourth wheel. After every sequence of eight semi-oscillations, the lever is lifted. The wolf-tooth wheel advances by one tooth and moves the fourth wheel by 6 degrees, which causes the seconds hand to jump forward by one second.

The top of every hour is automatically announced with a gentle tone. A slide in the case flank at 10 o'clock can be used to isolate the hammer and disable the automatic hour strike. The mechanism is the subject of the fourth patent application.

The substantial effort invested in these attractive complications is manifested by the 438 meticulously finished parts contained in the refined caliber 32-650 HGS PS movement.

The Chiming Jump Hour is accommodated in a tonneau-shaped platinum case that is also crafted in the manufacture's own ateliers. Like the periphery and the minute circle of the dial, its flanks are decorated with intricate engravings of floral motifs. The small slide for enabling and disabling the hour strike is located at 10 o'clock. The watch has a solid platinum case back with the engraving "PATEK PHILIPPE GENEVE 175e Anniversaire 1839 - 2014".

At 12 o'clock, the gold dial features an aperture for the digital hour indication. The minute hand revolves in the off-center minute circle that dominates the top half of the dial while the prominent seconds subdial appears at 6 o'clock.

The Patek Philippe Chiming Jump Hour Ref. 5275 is worn on a shiny black alligator strap secured with a platinum fold-over clasp. It bears the engraved inscription "PATEK PHILIPPE 1839 - 2014" as well as an engraved Calatrava cross in the middle.
The watch comes in a limited anniversary edition of 175 pieces.