Rotary escapement for timepiece
AssigneeLes Fabriques d'Assortiments Reunies
InventorsRoland Dubois, Alexandre Antoine Bernasconi
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Abstract
A timepiece escapement has a balance carrying an eccentric pallet pin periodically and regularly oscillating forward and backward about a balance axis with the pin engaging on each forward oscillation between the teeth of an adjacent escape wheel so as angularly to step this escape wheel. The pin is engageable with the escape wheel through a predetermined lift angle which is equal to less than half of the engagement angle during which the pin is within the orbit of the teeth of the escape wheel and, therefore, prevents this wheel from rotating independently of the balance.
Claims6
In a timepiece escapement wherein a balance carrying an eccentric pallet pin periodically and regularly oscillates forward and backward about a balance axis with the pin engaging on each forward oscillation between the teeth of an adjacent escape wheel rotatable about a parallel wheel axis to displace said wheel only during said forward oscillation about said balance axis through a predetermined lift angle centered on said balance axis, said pallet pin being engaged within the orbit defined by said teeth and substantially preventing rotation of said wheel independent of said balance during forward and backward oscillation of said balance through a predetermined engagement angle at least partially overlapping said lift angle, the improvement wherein said engagement angle is at least twice as great as said lift angle.
Dependencies are inferred from the claim text.