[New for 2022] Patek Philippe unveils new "single pusher chronograph" capable of measuring 1/10th of a second

At Watches & Wonders 2022, Patek Philippe unveiled the new 1/10th-Second Single Push-Button Chronograph, model 5470P-001. This model features two independent chronograph mechanisms and two central seconds hands, allowing it to measure time in 1/10th-second increments, as its name suggests. It features a newly developed manual-winding chronograph movement, the caliber CH 29-535 PS 1/10, which holds seven patents.

An all-new high-precision chronograph measuring 1/10 of a second with two coaxial second hands

　Patek Philippe announced a number of fascinating new products at Watches & Wonders. The grand finale of the collection was the slightly delayed 1/10th-second single push-button chronograph, model 5470P-001.

　Its greatest feature is undoubtedly the incorporation of an entirely new display and mechanism that allows time measurement to 1/10th of a second, with two independent chronograph mechanisms and two central second hands.

　The concentric seconds hand is a patented design, created by Patek Philippe's engineers in pursuit of maximum legibility. The watch features two central chronograph hands, each driven by its own mechanism and operating at a different speed.

　文字盤を1分で1周する第1の秒針は、内周のパール・マーカー上に通常の秒表示を行う。また赤色の第2の秒針は12秒で1周（通常のクロノグラフ秒針の5倍の速度）し、12のセクター（それぞれのセクターがさらに10のセクションに分割されている）からなる、文字盤外周のシュマン・ド・フェール（レールウェイ）型スケール上に1/10秒単位で表示されている。

　This allows the owner of this watch to instantly read the elapsed seconds displayed on the inner pearl markers and the elapsed time (i.e., the time since the last red marker) in tenths of a second displayed on the outer chemin de fer scale, while the elapsed minutes are displayed on the instantaneous 30-minute counter at 3 o'clock.

　This chronograph also features a single push button at the 2 o'clock position that sequentially starts, stops, and resets the time to zero. This "single push button" is reminiscent of the classic chronographs that have been popular with enthusiasts since the days of pocket watches.

A newly designed movement packed with patented technology

　The new mechanism employed in this watch is said to be as complex as a split-seconds chronograph. The new movement, caliber CH 29-535 PS 1/10, has an escapement that operates at 10 beats per minute and integrates a second chronograph mechanism with a rapidly rotating seconds hand, which requires a considerable amount of energy. To control and suppress this energy, Patek Philippe's engineers had to intervene in every detail of the movement. The key word that was given the utmost importance throughout the movement's development was "precision."

　The development of this movement began with a single mainspring, which supplies the entire movement with energy. To minimize fluctuations in the balance spring's amplitude and ensure the most consistent chronometric accuracy, Patek Philippe redesigned the mainspring to increase its efficiency. To increase available energy and the power reserve, the diameter of the barrel arbor was reduced and the number of mainspring turns was increased. Furthermore, a patented notch in the barrel arbor reduces stress on the hook during winding, eliminating the risk of damage from excessive force.

　To achieve these goals of reliability and precision, the watch is equipped with the Oscillomax® regulator, developed by Patek Philippe Advanced Research. Introduced in 2011 and covered by 17 patents, the Oscillomax® regulator is comprised of three innovative components that utilize all the advantages of Silinvar® technology.

　This Silinvar® technology is based on a derivative of silicon with exceptional physical and mechanical properties (lightweight, robust, anti-magnetic, etc.). The Oscillomax® regulator comprises a Spiromax® balance spring with a patented terminal curve and inner boss, a Pulsomax® escapement with extensively re-geometriced pallet and escape wheel, and a Gyromax® balance wheel in Silinvar® with a gold insert.

　This is the first time Patek Philippe has used the Oscillomax® regulator in a current collection since the launch of the Patek Philippe Advanced Research perpetual calendar Ref. 5550P in 2011. This decision played a decisive role in the excellent performance of the new movement that powers this watch. Despite its significantly higher energy consumption, this movement also ensures the high accuracy required by the Patek Philippe Seal: within +/- 3 seconds per day.

A user-first chronograph mechanism

　The biggest challenge in this model was the quality of the 1/10th of a second display. The two chronograph displays had to be perfectly synchronized, and of course the 1/10th of a second chronograph hand had to move smoothly, without jumps or vibrations. Here too, Patek Philippe's engineers developed an innovative solution, which they incorporated into this model.

　The 1/10th of a second mechanism receives its energy from the fourth wheel of the base movement via a drive wheel. This drive wheel has a new two-layer structure, with a flexible arm for the upper gear and a rigid arm for the lower gear. This patented, compact, and energy-efficient anti-backlash structure allows the teeth of the drive wheel to exert an elastic force on the clutch wheel, eliminating the risk of hand vibration.

　When the pusher is pressed to start the chronograph, the drive wheel, which rotates at one revolution per minute, engages with the 1/10th-second pinion, which rotates once every 12 seconds, five times faster than the drive wheel. To make this "acceleration" possible, the 1/10th-second pinion is micro-toothed. Its diameter is 1.469 mm, its tooth thickness is 30 μm, and it has 136 teeth. The preload applied by the clutch wheel to the pinion minimizes tooth backlash. All of these measures maximize the precision of the display.

　Another important feature is its shock resistance in practical use. The new caliber CH 29-535 PS 1/10 had to withstand all the constraints and risks of everyday use. To achieve this, Patek Philippe developed two patented mechanisms.

　One is a shock absorber hook that holds the clutch lever in place throughout the entire process of measuring short periods. The other is the use of the unbalanced weight of the 1/10th-second chronograph components (i.e., the center of gravity is shifted from the center of rotation). When an impact occurs, the acceleration of all components exposed to the impact is compensated rather than accumulated. As a result, all components are held in the required position, eliminating any impact on the watch's functionality.