Once again independent Swiss watch brand Armin Strom goes above and beyond the expected. The Armin Strom Gravity Equal Force has an all-new movement with declutch system.
Independent Swiss watch brand Armin Strom has been regularly bending the rules of traditional watchmaking — thinking outside of the proverbial box and introducing ever more precise and exciting timepieces. From its Dual Time Resonance watches to the Skeleton Carbon and the most recent Minute Repeater Resonance, this brand is on fire. Now Armin Strom introduces a watch– Gravity Equal Force — that is the start of an all-new collection for the brand: System 78. The System 78 collection (so named for the birth year of each of its two co-founders) is designed to offer innovative watchmaking at highly competitive prices for the segment.
In the Gravity Equal Force watch, the brand modifies the traditional mainspring barrel, adding a stopwork declutch mechanism with automatic winding to create consistent power delivery to the balance. BY transmitting equal force to the balance, there is an increase in the consistency of rate.
The 202-part caliber ASB19 movement for the Armin Strom Gravity Equal Force features Automatic winding with micro rotor, Geneva-drive equal force barrel, offset display with subdial seconds, and Balance wheel with 4 regulating screws
New Movement Architecture
To accomplish its goal, Armin Strom “developed an ingenious stop-works declutch system that operates inside the mainspring barrel to limit the torque delivered to the balance, providing smooth power delivery. This represents the first time a stop-works declutch mechanism has been added to an automatic winding movement.”
Additionally, the watch houses a barrel that operates differently from the traditional mainspring barrel that rotates around the arbor. Claude Greisler, head watchmaker at Armin Strom, developed a motor barrel system where the barrel housing stays locked after winding so that the arbor can rotate to drive the going train. The result of this state-of-the-art design is a low-friction axis of rotation that is more stable. It still offers 72 hours of power reserve.
The watch is equipped with a unidirectional winding micro rotor that is visible from the dial side, where the architecture of the Caliber ASB19 movement is mesmerizing. In fact, the watch features an off-center dial and a slimmer case in a 41mm diameter. It also depicts multiple bridges that echo the era of the pocket watch, which was the inspiration behind this movement.
The Armin Strom Gravity Equal Force kicks off a new collection from the brand: System 78 (named for the birth year of the co-founders).
Greisler, along with co-founder of the brand, Serge Michel, insist that everything the brand creates must incorporate something new and different that has been developed in the brand’s R&D department with an oath toward advancing horological technology. Crafted in stainless steel, the Gravity Equal Force retails for $15,600.
“We have reinvented the whole functionality of an automatic watch movement to bring another level of precision and to offer our collectors more assurance for reliable daily wear,” says Greisler.
Gravity Equal Force Declutch Mechanism
Until we have a chance to go hands on with this watch, and talk with the minds behind it, we offer a brief look at how the Declucth Mechanism works to offer constant force.
“Utilizing a Geneva wheel mounted to the barrel housing cover, the rotation of the mainspring barrel is limited to just 9 full turns out of a possible 12.5. This represents the central 72% of the mainspring’s potential torque curve, the flattest and most consistent portion. As the barrel housing unwinds around the arbor, a pin counts off the rotations on the Geneva wheel until it reaches the locked position and prevents further unwinding. This limit keeps the power delivery to the balance as consistent as possible and the amplitude in optimal range. Once it reaches the upper limit, the declutch mechanism guarantees the slip of the mainspring and allows the micro rotor to turn evenly when fully wound.
A small declutch lever is attached to the Geneva wheel that marks its rotation and power reserve from full to empty. Sitting atop the barrel cover, the power reserve location will change as the watch is wound, providing some playful variation in the dial display.”
The Gravity Equal Force, which, as mentioned launches the System 78 collection, will replace the brand’s Single Barrel Collection. Also as mentioned, this line will represent the new entry level price point for Armin Strom.
Armin Strom Gravity Equal Force
Technical specifications: Gravity Equal Force
Ref. ST19-GEF.90.AL.M.35
Indications: Hours, minutes, seconds, power reserve indicator
Movement: Armin Strom manufacture Caliber ASB19
Automatic winding with micro rotor, Geneva-drive equal force barrel, offset display with subdial seconds
Regulating system: Balance wheel with 4 regulating screws
Power reserve: Geneva stop-work limited to 72 hours
Dimensions: 35.52 mm x 11.67 mm
Frequency: 3,5 Hz (25,200 vph)
Finishing: Hand-finishing to the highest quality level
Jewels: 28
Number of components: 202
Case: Stainless steel
Sapphire crystal and case back with anti-reflective treatment
Diameter: 41 mm
Height: 12,65 mm
Water resistance: 3ATM
Dial: Offset with subdial
Hands: Manufactured by Armin Strom – stainless steel with hand finishing
Straps: Delivered with a genuine black alligator leather strap and stainless steel ardillon buckle. A stainless steel double-folding clasp is an option.
Price: $15,600
Reverse side of the movement of the Armin Strom Gravity Equal Force
