A timepiece includes a mechanical oscillator and an electromechanical transducer formed by an electromagnetic assembly including a coil and a magnet mounted on the balance of the mechanical oscillator. The induced voltage signal, produced by the electromagnetic transducer during each oscillation, exhibits, in a first half-alternation between the oscillator passes via the neutral position thereof, a first lobe of maximum amplitude having a first polarity and, in a second half-alternation following a passage via the neutral position, a second lobe of maximum amplitude having a second polarity opposite the first. An electric converter includes two power supply capacitors and a device for regulating the medium frequency of the mechanical oscillator. The first power supply capacitor is charged merely with a positive voltage whereas the second capacitor is charged merely with a negative voltage. A load pump is arranged to transfer electric loads between the two capacitors according to a time drift of the mechanical oscillator relative to a time base.

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.

A piezoelectric element for an automatic frequency control circuit. The element includes a balance spring formed of a piezoelectric crystal strip, a first electrode connected to the automatic control circuit, and disposed on at least a first side of the strip, and a second electrode connected to the automatic control circuit and disposed on at least a second side of the strip. The first and second electrodes are placed on one portion or over the entire length of the balance spring in a predetermined angular distribution.

The present invention concerns a piezoelectric element (3) for an automatic frequency control circuit. The element includes a balance spring (7) formed of a strip of piezoelectric material, a first electrode connected to the automatic control circuit, and disposed on all or part of one side of the strip, and a second electrode connected to the automatic control circuit and disposed on all or part of another side of the strip of piezoelectric material. The element further comprises at least two discontinuous layers of an insulating material, each discontinuous layer of insulating material being disposed on at least one side of the strip of piezoelectric material and separating a first electrode from a second electrode. The discontinuous layers of insulating material are distributed on predetermined portions of the balance spring substantially forming arcs, with a predetermined angular periodicity.

The invention concerns an oscillator for a timepiece movement, comprising a staff rigidly connected to a balance carrying first and second bipolar magnets spaced apart from the staff and capable, depending on the angular position of the balance, of being positioned alternately within range of a magnetic field produced by a fixed bipolar magnet, the latter being located on the trajectory of the first and second bipolar magnets and being arranged in such a way that, when one of the bipolar magnets approaches the fixed bipolar magnet, identical polarities are located opposite each other in order to produce a repulsive force. The oscillator further comprises a pallet assembly and an escape wheel for establishing a kinematic connection between a source of energy of the timepiece movement and the balance staff, and arranged in such a way that the balance is capable of having a sustained periodic oscillating movement of an amplitude greater than 90 degrees.

Watch with a timepiece movement, a resonator mechanism, including a magnetic escapement mechanism including an escape wheel set including a magnetized track, with a succession of areas according to a scrolling period in which its magnetic features are repeated, each area including an increasing magnetic field ramp followed by a magnetic field barrier with an increasing field and of higher field gradient that that of the ramp, the track includes a continuous, closed magnetic layer over the entire periphery of the escape wheel set, of constant thickness and variable width, whose geometry defines these magnetic field ramps and barriers, this escape wheel set cooperating with a sprung balance via a pivoting magnetic stop member comprising a pole piece arranged to cooperate alternately with an internal track and an external track of the magnetic layer.

A timepiece mechanism including a first component and a second component configured to cooperate with each other in a relative motion on a trajectory in an interface area, wherein a first path of the first component includes magnetic and/or electrostatic actuation components, configured to exert a contactless stress on complementary magnetic and/or electrostatic actuation components included in a second path belonging to the second component. Throughout a monotonous relative movement of the second path with respect to the first path, interaction energy between the first component and second component has a variable gradient with at least one position of discontinuity of the gradient, which corresponds to a variation in the contactless stress, the position of discontinuity of the gradient corresponding, in a variant, to an abrupt variation in the contactless stress.

An horological movement includes an analogue time display, a geartrain, a barrel and an electromechanical oscillator, which is formed of a resonator, including a balance and a piezoelectric balance-spring, and a mechanical escapement, and further includes an electronic control circuit connected to an electrical energy source and arranged to be able to control the application of an electrical voltage on at least one electrode of the piezoelectric balance-spring so as to generate driving electrical pulses for the oscillator. The horological movement is configured such that the barrel is capable, in a first main state, of maintaining alone a functional oscillation of the oscillator with a first amplitude, while in a second main state, the electronic control circuit powers the piezoelectric balance-spring to maintain, partially or fully, the oscillation of the resonator with a second amplitude greater than the first amplitude for any spatial orientation, the second amplitude being preferably constant.