The Rolex Dynapulse Escapement and the Calibre 7135 Deciphered

Rolex has modified… Not marginally, however considerably. We knew the model was able to being reasonably unpredictable and able to daring artistic strikes, resembling bubble-decorated dials and watches with guilloché sample. The occasions when Rolex was merely revamping a set each 10 years, by implementing incremental upgrades, and releasing a brand new color of dial each two years, are gone. Beneath the lead of Jean-Frédéric Dufour (JFD, as staff name him internally), the model has reworked. What we now have witnessed at Watches and Wonders 2025 goes many steps additional than conventional innovation. We’re not particularly talking concerning the Land-Dweller as a watch, regardless that it carries nice significance, however what beats within the watch. There may be certainly a real watchmaking revolution inside its calibre 7135 named the Dynapulse escapement. And we’ll attempt to clarify all the pieces about it.

Earlier than we publish our hands-on article with the Land-Dweller (which might be achieved within the coming days), we needed to dive deep into its motion and one thing that I’m not shy of calling revolutionary: the Dynapulse escapement. Let’s first briefly state what Dynapulse isn’t and what it’s. Opposite to earlier beliefs, which rose from findings in patents filed by Rolex a number of weeks earlier than Watches and Wonders 2025, the Dynapulse escapement is NOT a pure escapement. There have been some misunderstandings right here, because of the complexity of this innovation. We determined to ask a grasp watchmaker, Karsten Fraessdorf, to present his views on this new kind of escapement.

So what’s the Dynapulse escapement all about? Properly, two issues particularly: high-frequency and high-efficiency. In a really succinct description, Dynapulse is a groundbreaking, extremely modern but surprisingly easy new kind of escapement. It may possibly’t be in comparison with something current. It’s not a Swiss lever escapement, which Rolex already drastically improved with its Chronergy escapement launched in 2015. It’s not a pure escapement as per Breguet’s idea, or later adopted by George Daniels, Derek Pratt or Laurent Ferrier. It’s not similar to the Twin Ulysse escapement. It’s one thing completely new and significantly spectacular within the context of a motion produced at an industrial scale, by a watchmaking firm that’s often recognized to deal with comparatively conservative options and reliability. So, all of the extra coming from Rolex, the Dynapulse escapement is staggering. For many who stated that Rolex wasn’t a correct watchmaker, right here’s your counterargument. 

Within the personal phrases of Frank Vernay, head of actions at Rolex, Dynapulse is a “sequential distribution escapement (…) that provides excessive vitality effectivity, roughly 30 per cent greater than a standard Swiss lever escapement, whereas taking over no more room.” It’s, in additional technical phrases, a double-wheel, indirect-tangential impulse escapement made virtually completely from silicon, utilizing extremely complicated but surprisingly natural geometry for its two wheels and centered virtually completely on effectivity. The entire concept was to have the ability to transfer as much as a 5Hz frequency – which is, all issues thought-about, higher for accuracy – whereas not consuming extra vitality and never taking more room than a extra conventional Chronergy escapement beating at 4Hz.

This novel escapement alone is protected by seven patents. “A lot of the work focused on simplifying the form of the wheels and the impulse rocker in order that these parts might be made out of silicon. Becoming such a fancy mechanism into the identical area as a standard Swiss lever escapement constituted an actual technological problem, as did the manufacturing and pre-assembly of the small parts in silicon,” says Vernay. 

What makes Dynapulse totally different from a pure escapement whereas nonetheless retaining a double-wheel structure? As we explored on this article concerning the pure escapement in Laurent Ferrier’s watches, this resolution was imagined (as all the time…) by Abraham-Louis Breguet to compensate for the failings of the Swiss lever escapement – low effectivity, want for lubrication, excessive stage of friction, however simple to provide and self-starting – which remains to be in use in about 99% of mechanical watches. Breguet’s concept was to mix the self-starting capability of Mudge’s 1755 lever escapement with the frictionless operation of one other resolution, the detent escapement. Breguet’s concept was to create an escapement incorporating two escape wheels. The escapement is alleged to be “pure” as a result of the impulses are transmitted from the escapement wheels to the steadiness wheel as straight as attainable. There isn’t a sliding friction, which is without doubt one of the principal weaknesses of the Swiss lever escapement, and they don’t require lubrication. Working in alternation, these give two impulses per oscillation, one in every route. Breguet confronted main points within the improvement of the pure escapement, principally associated to the shortage of expertise, however the pure escapement got here again in high-end watches just lately, solely produced at an artisanal scale. 

The explanation why the Dynapulse escapement isn’t “pure” is pretty easy. It doesn’t give direct impulse to the steadiness; solely one of many two wheels is definitely linked to the gear practice. As the primary escape wheel is powered by the silicon-made fourth wheel, the opposite is pushed by the movement of the primary. Additionally, Dynapulse’s wheels don’t give direct impulse to the steadiness however as an alternative are linked to an impulse rocker, which in flip provides impulse to the steadiness. 

The impulse rocker is used to manage the locking and releasing features, thus giving the impulse to the steadiness. There are two escape wheels, considered one of which is inoperative each different half-oscillation and easily needs to be dragged alongside, after which act on an anchor… In accordance with watchmaker Karsten Fraessdorf, “accelerating two escape wheels that should meet up with the steadiness wheel at its quickest? That’s like Usain Bolt with a 10-kilo backpack for the reason that anchor is the most important vitality waster in wristwatches.” So why would this entire conception make sense?

Fraessdorf provides that the genius of Dynapulse partially lies within the geometry of the wheels. “As a substitute of the standard 15 or 20 enamel, with an extra upward development in improvement, Rolex selected to have solely 6 enamel. This leads to a pitch of 60 levels in comparison with the standard 24 and even simply 18 levels,” he stated to us, including that “this enabled the designers to make the escape wheels extraordinarily small in relation to the steadiness wheel diameter. Not solely does this drastically cut back their very own weight, however it additionally considerably reduces centrifugal forces, i.e., the inertia of the wheels. The value for this was the implementation of an in any other case uncommon fifth wheel within the gear practice, however the drawback of the extra friction is negligible in comparison with the acceleration functionality of the escape wheels, which has elevated enormously.” He ended up with a quite simple analogy: “Usain Bolt’s backpack has disappeared. As a substitute, he acquired an acceleration assist within the beginning block.”

So as soon as once more, Dynapulse is all about effectivity, and the truth that this new escapement operating at 36,000 vibrations per hour doesn’t eat extra vitality than the Chronergy escapement of the Rolex Calibre 7140 discovered within the Perpetual 1908 (the identical base motion) and operating at solely 28,800 vibrations per hour, is spectacular. In each, the facility reserve is rated at roughly 66 hours.

After all, this isn’t the entire story. Fraessdorf provides that the surfaces and shapes of the enamel additionally play a task, as utilizing DRIE course of, it was attainable to provide a sophisticated tooth tip, in addition to an impulse floor that’s convex reasonably than flat, as soon as once more limiting friction – in reality, there’s no sliding friction anymore, as in a lever escapement, however as an alternative a rolling movement with the contact surfaces that press in opposition to one another reasonably than slide. The outcomes are stunning natural shapes for the enamel. Mixed with main upgrades on the anchor, in addition to on the locking and unlocking moments, this leads to a extremely environment friendly escapement that would just about run with out oil, but Rolex emphasised using “oil reasonably than grease for lubrication. Utilized utilizing a curved precision needle, the oil is distributed on a scale of nanolitres.” 

That is for the escapement half, also referred to as the Dynapulse escapement. However there’s extra to the calibre 7135, with some spectacular expertise additionally discovered on the remainder of the regulating organ. For example, the steadiness workers is comprised of white ceramic that not solely comes with excessive energy however can be polished to a nanometric scale. This sprucing is carried out to forestall any fissures or injury within the occasion of affect whereas creating a wonderfully easy floor end that after once more provides to the motion’s effectivity. This materials can be paramagnetic – Rolex doesn’t make any claims concerning the general magnetic resistance of its motion, however we will assume that it’ll survive fairly excessive magnetic fields – doubtlessly to METAS ranges, however the Grasp Chronometer certification is just applied at Tudor.

Then, there’s the steadiness itself, which retains a traditional free-sprung nature however is product of “optimised brass.” As soon as once more a pending patent (EP4399575A), the fabric right here is used rather than conventional Glucydur (a beryllium, copper and iron alloy) is a lead-free brass often called CuZn21Si3P. It’s stated to have larger anti-magnetic properties. Lastly, the calibre 7135 is supplied with the model’s Syloxi hairspring, product of silicon. It isn’t a primary for the model and has been seen in numerous ladies-sized fashions in addition to within the Calibre 7140 of the 1908 Perpetual. 

But, because of the novel nature of the escapement and the 5Hz frequency, the hairspring needed to be redesigned and recalculated. It options reshaped coils, which at the moment are thicker to confer larger rigidity. As soon as once more, its geometry is very particular with two anchor factors underneath the steadiness bridge. This additionally meant connecting the ceramic steadiness workers to new, optimised Paraflex shock absorbers – one at every finish of the workers, on the pivots – that embody an enhanced leaf spring that ensures optimum repositioning of the workers after a shock.

In conclusion, and to cite Karsten Fraessdorf, “Rolex has made an excellent transfer with the Dynapulse escapement. Who would have thought that the lever escapement, a normal in mechanical wristwatches for over 250 years, might be turned on its head like this and considerably improved within the course of?” Above all of the technical facets, it’s the magnificence of the answer that have to be applauded. Behind its obvious simplicity, the Dynapulse escapement is the results of years of analysis and improvement and is extraordinarily refined within the high quality particulars of its structure and geometry. Mechanical innovation and watchmaking are very a lot on the centre of consideration at Rolex, which appears to liberate itself from traditionalism and constraints. And what’s extra spectacular is that we’re speaking about large-scale watchmaking, not prototyping. “Rolex doesn’t use new applied sciences to repeat the previous, however reasonably units its personal new boundaries,” concludes Fraessdorf. 

For extra particulars, please go to rolex.com.