Specially dedicated to passionate collectors and aficionados of high horology creations, the World Time Chronograph Ref. 5930 is a rare offer from the prestigious Geneva based watch manufacture as it incorporates two long-standing Patek Philippe specialties – Chronograph & World Time – that true connoisseurs so far have seen only in a single piece from the 1940s.
To date, only a single Patek Philippe World Time Chronograph is known, a one-of-a-kind piece crafted over 70 years ago. It is wristwatch no. 862442 dated 1940 (Patek Philippe Museum Inv. P996) featuring a dial with pulsimeter and asthmometer scales, and it probably belonged to a physician.
With the Ref.5930, Patek Philippe is now adding the World Time Chronograph as a new member to its regular collection, simultaneously upgrading it to the 21st-century state of the art. This is an ambitious venture, because both the World Time watch and the chronograph have made epochal progress at Patek Philippe since 1940. The mechanisms have become more precise but also more complex, so it was challenging to integrate both functions into one movement.
The development of a mechanical chronograph featuring 24 time zones is an adventure in space management. The classic World Time watch does not have a seconds hand, but the chronograph features a long trotteuse and a 30-minute counter.
Where conventional chronographs have a scale graduated in fractions of a second, the World Time Chronograph has a moving city disk with place names that each represent one of the 24 international time zones as well as a moving 24-hour ring on which the time is indicated for the city that stands directly above it.
The elements of the new mechanical CH 28-520 HU movement are the self-winding CH 28-520 PS chronograph caliber with column-wheel control and a vertical clutch as well as the proven World Time module based on a concept developed by Genevan watchmaker Louis Cottier in the 1930s. Subsequently, Patek Philippe further optimized this ingenious solution and had two important refinements patented in 1959 and 1999.
The chronograph movement and the World Time mechanism were enhanced with extensive modifications. Axes were shifted, bridges thinned and newly designed, and component clearances changed such that the caliber CH 28-520 HU can legitimately be called a new movement. It embodies everything that belongs to Patek Philippe’s proud watchmaking heritage while featuring technical and functional innovations that make it a latest-generation movement. This also applies to its operation, in line with Patek Philippe’s commitment to user-friendliness.
The chronograph has a start/stop pusher at 2 o’clock and a reset pusher at 4 o’clock that also doubles as a flyback pusher. When it is pressed while the chronograph is running, the sweep hand flies back to zero and a new time measurement is started automatically. Because the chronograph hand is powered via a vertical clutch, it can also be used as a permanently running seconds hand without risking undue wear and without affecting the rate accuracy and power reserve of the watch.
The World Time function is also very easy to use: The hour and minute hands indicate the time in the city and time zone whose name is shown at 12 o’clock. The time in the 23 other zones can be quickly and easily determined with the city disk and the two-colored 24-hour ring which instantly tells the user whether it is day or night in the respective city and time zone. When traveling from one time zone to the next, pressing the corrector button at 10 o’clock advances the city disk and the 24-hour ring counter clockwise in one-hour steps as well as the hour hand clockwise, also in one-hour steps. The correction is finished when the city name of the destination time zone is at 12 o’clock. During this process, the World Time mechanism and the hour hand are uncoupled from the movement, so neither the amplitude of the balance nor the steady progression of the minute hand are affected. The chronograph hand also keeps moving without the slightest irregularity.
The classic 18K white gold round case of the new Ref.5930 features the same winglet-style strap lugs that were a key design element of the 1940s and 1950s World Time watches. The time-zone correction button is still at 10 o’clock and has the same rectangular profile as the two chronograph pushers. Their shape is a recurring theme in the manufacture’s classic chronographs.
Further, the case is endowed with a sapphire-crystal display back that reveals the stunning beauty and flawless finish of the movement. The center of the rotor is decorated with delicate perlage, while the centrifugal mass itself features circular graining and an engraved Calatrava cross. The circular graining is repeated on the silvery bright rhodiumed bridges. Their polished chamfers, polished countersinks, and gold-filled engravings comply with the directives of the Patek Philippe Seal. They highlight beautiful contrasts against the gleaming red bearing jewels, the golden hue of the Gyromax® balance, and the purple-blue shimmer of the patented Spiromax® balance spring in Silinvar®; with its Patek Philippe terminal curve, it combines the concentric breathing of a Breguet hairspring with the svelte silhouette of a classic flat balance spring.
On the dial, both complications are seamlessly integrated. The outermost display element in blue lists the 24 city names that each represents an entire time zone. It has been updated with new cities for some time zones – for instance Dubai instead of Riyadh or Brisbane instead of Nouméa – and takes into account the fact that Moscow changed its local time from UTC+4 to UTC+3.
A small gap between the city disk and the 24-hour ring accommodates the seconds scale for chronograph measurements. It is a narrow white circular scale with fourth-of-a-second graduations. This subdivision reflects the movement frequency of 4 hertz (28,800 A/h), which allows times to be stopped to an accuracy of one-eighth of a second. The 24-hour ring, which continuously rotates counter clockwise, doubles as a day/night indicator. It has bright numerals on a dark background and a moon symbol for the nocturnal hours as well as dark numerals on a bright background and a sun symbol for the daylight hours.
The center of the dial is designed along the lines of the World Time watch tradition. It sports a subtle manually guilloched decoration interrupted only by the 18K white-gold index markers and the 30-minute chronograph counter. This subdial stands out with a delicate white gold surround, the white minute scale, and the discreet circular-grained finish. The design is not only an artistic exploit but also assures optimized legibility.
The new Patek Philippe World Time Chronograph Ref. 5930 launches in 2016 in a version with a white-gold case and a blue, hand-guilloched dial center. It is worn on a hand-stitched matt navy blue alligator strap with large square scales to match the dial. An 18K white-gold Calatrava fold-over clasp keeps the watch comfortably secured to the wrist.
Ref. 5930 World Time Chronograph
Caliber CH 28-520 HU
Self-winding mechanical movement, column-wheel chronograph, vertical clutch, local time, display of 24 time zones, day/night indication
Diameter: Overall: 33.00 mm
Basic caliber: 30.00 mm
Time-zone module: 33.00 mm
Height: Overall: 7.91 mm
Basic caliber: 4.9 mm
Time-zone module: 3.01 mm
Number of parts: 343
Number of jewels: 38
Power reserve: Min. 50, max. 55 hours
Centrifugal mass: Central rotor in 21K gold, unidirectional winding
Frequency: 28,800 semi-oscillations per hour (4 Hz)
Balance spring: Spiromax®
Balance spring stud: Adjustable
– Pulled out: To set the time
– Pushed in: To wind the watch
• Local time in hours and minutes
• Chronograph hand (trotteuse)
• 30-minute chronograph counter
• City disk with 24 place names
• 24-hour ring with day/night indication in colors and sun/moon symbols
Chronograph start and stop at 2 o’clock
Chronograph reset and flyback at 4 o’clock
Time zone adjustment at 10 o’clock (synchronized adjustment of displays in one-hour steps for the hour hand and 1/24th counter clockwise increments for the city disk and the 24-hour ring)
Patek Philippe Seal
18K white gold
Sapphire-crystal case back
Water resistant to 30 meters (3 bar)
Case dimensions: Diameter: 39.50 mm
Length (across lugs): 48.23 mm
Width (3 to 9 o’clock incl. crown): 42.85 mm
Thickness (crystal to display back): 12.86 mm
Width between lugs: 21 mm
– City disk blue, names printed white
– 24-hour ring with day/night indication in color and sun/moon symbols (day: blue numerals on silvery background; night: white numerals on blue background)
– Center navy blue, hand-guilloched
Applied baton hour markers in 18K white gold
Hours and minutes: Dauphine hands in 18K white gold, 3 facets, Superluminova coating
Parfil chronograph hand in rhodiumed steel
30-minute counter hand, baton style, counter balanced, rhodiumed steel
Hand-stitched alligator with large square scales
Matt navy blue with fold-over clasp in 18K white gold