A timepiece includes a mechanical oscillator, formed of a mechanical resonator, and a device for regulating the frequency of the mechanical oscillator. This regulation device includes an auxiliary oscillator, an electromechanical device for stopping the mechanical resonator, a sensor arranged to detect the passage of the mechanical resonator via the neutral position thereof, and a measuring device arranged to measure a time drift of the mechanical oscillator. The regulation device is arranged to stop, during a given alternation, the natural oscillation movement of the mechanical resonator selectively either momentarily during a first half-alternation occurring before the passage of the mechanical resonator via the neutral position thereof when the time drift measured corresponds to at least a certain gain, or prematurely during a second half-alternation occurring after the passage of the mechanical resonator via the neutral position thereof when the time drift measured corresponds to at least a certain loss.

A method for manufacturing at least two mechanical parts to be arranged in a timepiece mechanism including magnetised functional areas having antagonistic polarities, the parts being arranged in a timepiece mechanism to cooperate with each other in relative displacement, the method including a step of constructing a blank of each of the two parts including at least one functional area from which the parts are able to cooperate with each other and a step of obtaining each of the parts including a sub-step of transforming said at least one functional area of the blank of each of these parts into a magnetised functional area from which emanates a magnetic field, at least one feature of which is configured so that this magnetic field participates in achieving a separation of the magnetised functional areas of the two parts when they are in a stop position in the mechanism.

A timepiece includes a mechanical oscillator, formed by a balance and a piezoelectric balance spring, and a control device for controlling the frequency of the mechanical oscillator. This control device is arranged to be capable of generating time-separated control pulses, each including a momentary decrease in an electrical resistance applied by the control device between two electrodes of the piezoelectric balance spring relative to a nominal electrical resistance. The control device is arranged to be capable of applying a plurality of control pulses during each time of a series of distinct correction times or without interruption in a continuous time window, in order to respectively synchronize the mechanical oscillator at a correction frequency whose value depends on a detected positive or negative temporal drift or at a desired frequency for the mechanical oscillator.

A timepiece includes a mechanical oscillator, formed by a balance and a piezoelectric balance spring, and a control device for controlling the frequency of the mechanical oscillator. This control device is arranged to be capable of generating time-separated control pulses, each including a momentary decrease in an electrical resistance applied by the control device between two electrodes of the piezoelectric balance spring relative to a nominal electrical resistance. The control device is arranged to be capable of applying a plurality of control pulses during each time of a series of distinct correction times or without interruption in a continuous time window, in order to respectively synchronize the mechanical oscillator at a correction frequency whose value depends on a detected positive or negative temporal drift or at a desired frequency for the mechanical oscillator.

A process for producing a metal alloy balance wheel by molding includes a) making a mold in the negative shape of the balance wheel; b) obtaining a metal alloy that has a thermal expansion coefficient of less than 25 ppm/° C. and is able to be in an at least partly amorphous state when it is heated to a temperature between its glass transition temperature and its crystallization temperature; c) putting the metal alloy into the mold, the metal alloy being heated to a temperature between its glass transition temperature and its crystallization temperature so as to be hot-molded and to form a balance wheel; d) cooling the metal alloy to obtain a balance wheel made of the metal alloy; and e) releasing the balance wheel obtained in step d) from its mold. The process also includes a step for over-molding flexible centering components in the hub.

A mechanical oscillator, formed of a mechanical resonator and a device for maintaining oscillation, and an auxiliary oscillator forming a reference time base including a synchronisation device arranged to slave the medium frequency of the mechanical oscillator on that of the auxiliary oscillator. The synchronisation device includes an electromagnetic braking device which is formed of a coil and at least one permanent magnet and arranged such that an induced voltage is generated between the terminals of the coil in each alternation of the oscillation of the mechanical resonator. The synchronisation device is arranged to be able to reduce momentarily the impedance between the terminals of the coil during distinct time intervals, any two successive time intervals exhibiting between the respective starts thereof a time distance substantially equal to a positive whole number multiplied by half of a set-point period for the mechanical oscillator.

Watch comprising a movement, with a timepiece balance wheel comprising a ring distinct from the balance rim, carried by a flange with respect to which this ring is movable in rotation to modify the position of inertia blocks elastically carried by the flange, each able to be indexed in different stable angular positions corresponding to a different inertia of the timepiece balance wheel, the movement further including an operating member movable between coupled and uncoupled positions which includes a stop means for immobilising the rim in a coupled position, and a control means for rotating the ring to modify the position of the inertia blocks in the coupled position, the watch including a crown controlling the control means, a rotating coupling ring controlling the coupling/uncoupling of the operating member through contactless interaction with an external adjustment tool.

Watch comprising a movement, with a balance comprising a ring distinct from the balance rim, elastically fixed to a flange with respect to which this ring is movable in rotation to modify the position of inertia blocks elastically carried by the flange, each able to be indexed in different stable angular positions corresponding to a different inertia of the balance, the movement including an operating member movable between coupled and uncoupled positions which includes a stop means for immobilising the rim in a coupled position, and a control means for rotating the ring to modify the position of the inertia blocks in the coupled position, the watch including a crown controlling the control means, a rotating coupling ring controlling the coupling/uncoupling of the operating member through contactless interaction with an external adjustment tool.

Watch comprising a movement, with a balance comprising a ring distinct from the balance rim, elastically fixed to a flange with respect to which this ring is movable in rotation to modify the position of inertia blocks elastically carried by the flange, each able to be indexed in different stable angular positions corresponding to a different inertia of the balance, the movement including an operating member movable between coupled and uncoupled positions which includes a stop means for immobilising the rim in a coupled position, and a control means for rotating the ring to modify the position of the inertia blocks in the coupled position, the watch including a crown controlling the control means, a rotating coupling ring controlling the coupling/uncoupling of the operating member through contactless interaction with an external adjustment tool.

A timepiece (2) includes an actuator, which applies braking pulses to the balance, which has an electromechanical device (6) and an electric control circuit (8). The device (6) includes a flexible member (16), formed by an elastic blade (20) and a mechanical element (22) defining a braking pad, and an electromagnetic system (10) formed by a coil carried by the flexible member and by a permanent magnet rigidly connected to a support (18) of the electromechanical device. When an electric pulse is provided to the coil, an electromagnetic force of repulsion is engendered between the coil and the permanent magnet so the mechanical element moves to a position of contact with the balance. To stabilise the rest position of the flexible member, a magnetic element (26) is rigidly connected to the coil to exert a magnetic return force complementary to the force of the elastic blade is provided.