Montblanc

As an horological highlight in the Heritage Chronometrie Collection, Montblanc’s new ExoTourbillon Minute Chronograph combines two of the most important chronometric complications: a chronograph to measure the duration of brief intervals and a patented tourbillon construction for absolute precision.

Montblanc debuted the patented ExoTourbillon mechanism, which was completely developed and built in the Manufacture in Villeret, as part of the Collection Villeret in 2010. Five years later, Montblanc returns to this complication to integrate it into Montblanc’s own monopusher automatic chronograph calibre in the Heritage Chronométrie Collection.

As a consequence of the architecture of a classically constructed movement, the balance’s centre of gravity temporarily strays from the axis of rotation due to the influence of Earth’s gravitational force, which is particularly troublesome when the timepiece is in a vertical position. A tourbillon mechanism compensates for this centre-of-gravity error by enclosing the escapement inside a carriage or cage that continually rotates around its own axis. Gravity’s accelerating effect during the first 180 degrees of the carriage’s rotation is offset by a corresponding deceleration during the second 180 degrees, so the watch’s average rate remains constant.

With this patented ExoTourbillon construction, Montblanc offers for the first time a stop-second function that directly halts the screw balance by means of a tiny spring. Such a construction rarely accompanies a tourbillon and is very useful whenever the wearer wishes to precisely set not only the hour- and minute-, but also the second-hand. Directly halting the balance in a tourbillon is a more precise construction than arresting the second-hand by halting the rotation of the tourbillon’s cage because the former instantly stops the balance and prevents the "after-swing" that can occur when the tourbillon’s cage is stopped. In order to precisely adjust the time, the tourbillon cage integrates a red marker in form of an arrow, which allows to read the seconds on the respective scale printed on the opening of the dial around the tourbillon.

This innovative Tourbillon construction is integrated in Montblanc’s own in-house developed chronograph calibre that combines all the elements of a traditional chronograph with a contemporary highly performant construction: monopusher with column wheel, efficient and precise vertical coupling, automatic winding and two barrels. Two semicircular counters with hands of different lengths to match the appropriate sectorial scales, enable the Heritage Chronométrie ExoTourbillon Minute Chronograph to tally elapsed seconds and minutes.

Different from the other models in the Heritage Chronométrie Collection, the Montblanc ExoTourbillon Minute Chronograph relies on a slightly different case construction. The bezel is not flat, but concave, which creates an attractive aesthetic effect and simultaneously protects the bezel against scratches. The facetted horns are satin-finished on the inside and polished on the outside. Montblanc’s emblem, crafted as a distinctive relief atop the crown is a distinguishing feature of the entire collection. The leather strap is made at the Montblanc Pelletteria, the Maison’s own leather manufacture in Florence, Italy. This timepiece is available in a 44-mm-diameter case crafted from 18K red gold.

Montblanc Heritage Chronométrie ExoTourbillon Minute Chronograph

Ident. 112542

Movement:  Montblanc Manufacture Calibre MB R230

Type of movement: Mechanical movement with double barrel, automatic winding mechanism, one-minute patented ExoTourbillon with stop-second mechanism

Chronograph: Monopusher with column-wheel and vertical coupling

Dimensions:  Diameter=33.7 mm; height=8.65 mm

No. of components: 296

No. of rubies: 44

Power reserve: Approx. 50 hours

Frequency: 21,600 A/h (3 Hz)

Hairspring: Flat

Plate: Rhodium plating and circular graining

Bridges: Rhodium plating and côtes de Genève

Gear-train: Special tooth profile improves the efficiency of the power transmission

Displays (watch):  Off-centre hours and minutes.  Date by hand on same axis as hour- and minute-hand, and off-centre subdial Patented ExoTourbillon at 6 o’clock (one revolution per minute to indicate the seconds) with a stainless steel tourbillon bridge

Displays (chrono):  60 elapsed seconds and 30 elapsed minutes Counters with double indication hands and corresponding sectorial scales

Special feature:  Travel function with rapid reset of hour-hand and date display either forward or backward.  Tourbillon can be stopped by directly halting the balance wheel

Habillage

Case: 18 K red gold (5N), polished case with satin-finished interhorns, concave bezel for scratch protection

Crystal: Scratch-resistant, domed, sapphire crystal with antireflective treatment on both surfaces

Back: Screwed 18 K red gold back with inset pane of sapphire crystal

Dimensions: Diameter=44 mm; height=14.79 mm

Watertightness: 3 bar

Crown: 18 K red gold (5N) with Montblanc emblem in raised relief

Push-piece:  Monopusher at "8 o’clock"

Dial:   Ivory grainé on the upper part and vertical satin-finished silver on the lower part, facetted indexes, Arabic numerals "3, 9, 12" as red gold-plated appliqués, red gold-plated sword-shaped hour-hand and minute-hand, date-hand with a little red crescent at its tip, chronograph with two white-lacquered counters (one counter for 60 elapsed seconds at "8 o’clock" and a second counter for 30 elapsed minutes at "4 o’clock"), double indication hands and corresponding sectorial scales

Wristband:  Black alligator-skin strap crafted at the Montblanc Pelletteria in Florence with 18K red gold pin buckle (5N)

Certified by the Montblanc Laboratory Test 500

Price 38’000 euros