Armin Strom Introduces the Gravity Equal Force P.03 for Collective

Secondly, the Gravity Equal Force is the first watch that combines a torque regulating mechanism with an automatic winding system. Automatic watches, when worn, are constantly being wound and as such, do not suffer from declining amplitude if the wearer is active. Torque regulating devices are thus more logical when implemented in hand-wound watches.

But in the event that an automatic watch is left dormant, be it over the weekend or because the owner has more than one watch, which is more likely the case in our reality, a stopwork mechanism still comes in handy at ensuring the inferior part of the torque curve is never reached.

However, combining an automatic movement with a traditional Maltese stopwork is not without its own set of challenges as the rotor will still attempt to wind the barrel after it is brought to a halt by the stopwork. As such, Armin Storm has developed a stopwork that is able to decouple itself from the winding mechanism when the watch is fully wound. The stopwork comprises of a finger on the arbour inside the barrel and a wheel shaped like a Maltese cross but with eight concave arms instead of four, followed by a uniquely shaped portion designed to both declutch when the watch fully wound and stop the barrel from unwinding fully, consequently only utilizing a portion of the mainspring where torque is constant. Even though force is restricted by the stopwork, the movement still delivers a power reserve of 72 hours, with a power reserve indicator on the barrel cover for reference.