"Gravity Equal Force" equipped with a new constant force barrel developed by Armin Strom

Armin Strom has unveiled another innovative new watch: a conventional mainspring barrel set upside down, incorporating a declutching mechanism and an automatic winding mechanism that delivers constant power to the balance.

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  The Gravity Equal Force is the first in the System 78 collection, Armin Strom's entry-level line, which aims to create innovative timepieces at competitive prices. The collection is named after the two founders, both of whom were born in 1978.
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  By turning the normal mainspring barrel upside down and driving the gear train via the barrel axle, and by winding the barrel box, performance is improved and wear is reduced.
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  This latest design delivers power through a more stable, frictionless mainspring pivot point and a barrel pivot point supported by precision jewel bearings, using only a portion of the mainspring to prevent it from fully rewinding, while still providing a 72-hour power reserve.
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  The power reserve of the mainspring, which is wound by a single-winding micro-rotor visible through the dial, is displayed on the barrel cover.
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  It differs from previous models in that it features a new off-center dial, a smaller, thinner case, and, most notably, a triple bridge inspired by pocket watches.
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  The development of the new model began with the goal of delivering uniform power to the regulating mechanism, and as a result, a declutching mechanism was incorporated into the barrel box, ensuring constant power delivery to the balance and escapement.
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  The Geneva wheel is mounted to the barrel box cover, limiting the mainspring's rotation to 9 full revolutions out of a possible 12.5. This represents 72% of the mainspring's potential torque curve, and is the flattest, most uniform portion of the curve. As the barrel box unwinds from its axle, a pin counts the Geneva wheel's rotations and stops further unwinding when it reaches its locked position. This ensures the most uniform power transfer to the balance, limiting amplitude while still providing maximum efficiency.
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  When the maximum winding limit is reached, a clutch separation mechanism allows the mainspring to slip, allowing the micro-rotor to rotate evenly even at maximum winding.
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  A cross-section of a typical barrel and barrel stem. In a typical design, a central axle rotates within the barrel on a jewel bearing, winding the mainspring. When fully wound, the axle remains stationary, allowing the mainspring to push against the barrel housing, continuing to drive the going train.
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  A cross-section of the newly designed motor barrel. A typical mainspring barrel rotates on an axle rather than supported by a precision jewel bearing, resulting in high friction and poor rotational precision. Armin Strom's motor barrel design reverses this, locking the barrel box after winding, allowing a more precisely supported axle to rotate and drive the gear train.
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  Caliber ASB19 - Dial side. Caliber ASB19 features a new layout and improved gear geometry and precise adjustment, resulting in smoother operation and more reliable function.
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  The offset dial makes the time display easy to read. The skeleton structure allows the barrel and micro-rotor to be seen, and the triple bridge, inspired by old pocket watches, creates a classic look.
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  The first in the System 78 collection, Gravity Equal Force, embodies impeccable finishes and technological innovation, offering an affordable entry point to Armin Strom.

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Newly developed Geneva constant-force barrel

　The concept of "Gravity Equal Force" is to transmit equal power to the balance, thereby maintaining a consistent rate. An evolution of the traditional stop-off mechanism, Armin Strom's revolutionary declutch stop-off system operates within the mainspring barrel, limiting the torque transmitted to the balance to ensure smooth power transfer. This is the first time that a declutch stop-off system has been incorporated into an automatic movement, and it has been named the constant-force barrel.

Triple Bridges Inspired by Pocket Watches

Beautiful traditional finish