A constant-force device for precise regulation of mechanical watch movements by means of a uniform transmission of force from the escape wheel to the regulating organ of the watch, this device being adapted to be integrated into a Tourbillon mechanism.
The movement (1) of the watch includes a constant force device (14) inserted in a going rain connecting a spring barrel (2) to an escapement having an escapement wheel and including a third wheel which completes one revolution in several minutes. The input element of the constant force device (14) is the third wheel (12), the output element of said device (14) being a second third wheel (20) connected via gearing to the seconds pinion (38). The second third wheel is secured to a star wheel (26) that only releases the train upstream of the constant force device once per minute, thus forming an independent minutes display because the minute hand (7) jumps forward at each minute. This arrangement minimizes the transmission of shocks between the constant force device and the escapement and can advantageously be combined with a tourbillon (40).
A storage device comprises a first seconds wheel, engaging with a mainspring, and a second seconds wheel, a setting wheel for connecting these two seconds wheels, a yoke on which said setting wheel is pivotably mounted, the pivot axis of this yoke and that of the second seconds wheel being coaxial, a stop wheel kinematically linked with said first seconds wheel, a finger fixedly connected to said yoke, a storage spring for exerting upon said yoke a force tending to separate said finger from said stop wheel, whereas the force exerted upon said setting wheel by said mainspring serves to press said finger against said stop wheel, so that the latter is wound to the point where a tooth of said stop wheel abuts against said finger.
A timepiece, in particular a wristwatch, includes a constant-force device for acting on an oscillating system, the constant-force device including a switching unit and a tensioning module having a primary spring-energy store and a secondary spring-energy store. A seconds shaft bearing a seconds wheel and a cam plate is driven to rotate constantly by the secondary spring-energy store. The seconds wheel drives the oscillating system, and the cam plate acts on the switching unit for the periodic tensioning of the secondary spring-energy store by the primary spring-energy store.
The tri-axial tourbillon comprises a cage (A) containing the balance (1), the escape wheel (2) and the escape pinion (3) rotating around an axis (A1) and mounted in a second cage (B) rotating around an axis (A2), the cage (B) in turn being mounted rotably in a third cage (C) rotating around an axis (A3) that is fixed relative to the timepiece, the three axes (A1, A2, A3) being perpendicular to each other.
The tangential impulse escapement includes a lever device (1) including a lever (3) driving a roller (65) and a ring (7) surrounding an escapement wheel set (8), said ring being fitted with pallet-stones (9, 10, 11, 12) for cooperating with the teeth (13, 14, 15, 16) of said wheel set, in order, alternately, to lock the latter then import an impulse to said roller. The escapement wheel set includes at least first (17) and second (18) coaxial secured wheels. The pallet pallet-stones (9, 11, 12) of the ring cooperate with the teeth (13, 15, 16) of the first wheel (17) with the exception of one (10), which is arranged for cooperating with the teeth of the second wheel (18).