One drawback of mechanical watches is having to reset the time after forgetting to wind them. To eliminate that minor tedium, Belgian watchmaker Ressence has come up with the Type 2 e-Crown Concept, a mechanical/electromechanical automatic wrist watch that resets itself when the glass is tapped.
At first glance, the Type 2 e-Crown Concept shows its pedigree with styling cues taken from other Ressence timepieces. But a closer look reveals something odd. There's no crown. Not only is the lack of a crown a bit jarring aesthetically, it also raises an obvious question. How do you set a watch that doesn't have one? The answer is found by tapping the glass, which makes the hands suddenly leap to the correct time.
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Part of the secret of this capability is found in a lever set in the back of the 45mm titanium case. This is used once by the wearer to set the time and then the watch takes over. But why a lever? That's due to Ressence replacing the traditional crown mechanism with an in-house, electromechanical, embedded system.
Translated into English, the Type 2 e-Crown Concept contains two separate modules. One is a purely mechanical, 500-part, automatic movement with the company's redefined and patented dial Ressence Orbital Convex System (ROCS) that links the movement together using a series of titanium discs and rings. On top of this is the electronic e-Crown module. The former does the usual job of telling the time, while the latter replaces the crown.
What the e-Crown does is record the initial time setting that then acts as a running reference in the event the wearer takes the self-winding watch off for an extended period, allowing the power reserve to run out. Tapping the glass brings the e-Crown online and it uses a small motor to reset the time without interfering with the movement's gear train.
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In addition to resetting the time, the e-Crown has other features. It also monitors the watch's performance and allows the wearer to switch between time zones and the e-Crown modes by double tapping the glass or connecting via Bluetooth to an optional smartphone app. This provides the options of geolocation, more precise time setting on a daily basis, a readout of performance and automatic switching between summer and winter time. It will even send a reminder when it's time to have the Type 2 serviced.
Ressence says that e-Crown has three modes. In full e-Crown mode, the watch is set to a precision of a second by the e-Crown and the app, semi-e-Crown uses only the e-Crown for minute-level precision, and manual returns the watch to the predigital age with no electronic oversight.
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The watchmaker also tried to make the Type 2 e-Crown Concept fully self-sufficient. Not only is the movement self-winding, but the e-Crown uses only 1.8 joules of energy per day. This is provided by a kinetic generator when worn, but if the watch is left to sit, 10 micro shutters automatically open to reveal photovoltaic cells and the e-Crown goes into sleep mode until the glass is tapped.
Because it's just a concept, the company isn't providing details about the watch's movement or exactly how everything works. Also, even though the Type 2 is going into production this year, the Concept is a one-off that isn't for sale.
Source: Ressence