Timepiece, has movement comprising balance-hairspring type resonator, and lever-wheel type escapement system, where escapement system is partly open-worked to reduce inertia of system, and balance oscillates specific vibrations per hour

摘要

The timepiece has a movement (5) comprising a balance (8) - hairspring (10) type resonator (9) and a Swiss lever (13) - wheel (11) type escapement system (7). The escapement system is partly open-worked to reduce inertia of the escapement system. The balance oscillates 72000 vibrations per hour. The wheel has a main projection face whose surface density is less than 0.7 milligram per square millimeter. The wheel and the lever are made of silicon dioxide coated single-crystal silicon. The lever has pallets that are made of ruby.