A rotary piezoelectric motor, in particular for a timepiece, the motor including: a rotor configured to rotate and actuate a mechanical device, a stator configured to rotate the rotor, the stator including a piezoelectric actuator, the piezoelectric actuator including a moving element whose movement causes the rotor to rotate in a first direction, the piezoelectric actuator including only two electrically actuatable resonators, the two resonators being connected to the moving element to move it against the rotor to cause it to rotate, the two resonators being arranged relative to the moving element so as to cause the moving element to oscillate in first and second directions different from each other, each resonator including a centre of rotation, the two resonators being disposed relative to the moving element so that, around each centre of rotation, the torque resulting from all the acceleration forces being applied in the plane of each resonator is zero.

A rotary piezoelectric motor, in particular for a timepiece, the motor including: a rotor configured to rotate and actuate a mechanical device, a stator configured to rotate the rotor, the stator including a piezoelectric actuator, the piezoelectric actuator including a moving element whose movement causes the rotor to rotate in a first direction, the piezoelectric actuator including only two electrically actuatable resonators, the two resonators being connected to the moving element to move it against the rotor to cause it to rotate, the two resonators being arranged relative to the moving element so as to cause the moving element to oscillate in first and second directions different from each other, each resonator including a centre of rotation, the two resonators being disposed relative to the moving element so that, around each centre of rotation, the torque resulting from all the acceleration forces being applied in the plane of each resonator is zero.

A piezoelectric resonator for a rotary motor, the resonator including a stationary base and an oscillating mass extending around a longitudinal axis, the oscillating mass having an inertia-block. The resonator includes a flexible blade guide connecting the oscillating mass to the base, so as to be able to cause the oscillating mass to oscillate about a centre of rotation in a balance movement, the flexible guide including a first RCC-type pivot provided with an intermediate moving element, a first pair of flexible blades connecting the base to the intermediate moving element, and a second pair of flexible blades forming a second RCC-type pivot connecting the intermediate moving element to the oscillating mass, the piezoelectric resonator including a first flexible blade connecting the intermediate moving element to the base, the first flexible blade including at least in part a piezoelectric material that can deform the first flexible blade and cause the oscillating mass to oscillate.

A piezoelectric resonator for a rotary motor, the resonator including a stationary base and an oscillating mass extending around a longitudinal axis, the oscillating mass having an inertia-block. The resonator includes a flexible blade guide connecting the oscillating mass to the base, so as to be able to cause the oscillating mass to oscillate about a centre of rotation in a balance movement, the flexible guide including a first RCC-type pivot provided with an intermediate moving element, a first pair of flexible blades connecting the base to the intermediate moving element, and a second pair of flexible blades forming a second RCC-type pivot connecting the intermediate moving element to the oscillating mass, the piezoelectric resonator including a first flexible blade connecting the intermediate moving element to the base, the first flexible blade including at least in part a piezoelectric material that can deform the first flexible blade and cause the oscillating mass to oscillate.

A piezoelectric resonator, in particular for a rotary piezoelectric motor, the resonator including a stationary base and an oscillating mass extending around a longitudinal axis, the oscillating mass being provided with at least one flyweight, preferably two opposing flyweights, wherein the resonator includes a flexible guide connecting the oscillating mass to the base, so as to be able to cause the oscillating mass to oscillate about a centre of rotation in a pendulum movement, the flexible guide comprising at least a first flexible blade connecting the base to the oscillating mass, the first flexible blade comprising at least in part an electrically actuatable piezoelectric material for deforming the first flexible blade and causing the oscillating mass to oscillate.

A piezoelectric resonator, in particular for a rotary piezoelectric motor, the resonator including a stationary base and an oscillating mass extending around a longitudinal axis, the oscillating mass being provided with at least one flyweight, preferably two opposing flyweights, wherein the resonator includes a flexible guide connecting the oscillating mass to the base, so as to be able to cause the oscillating mass to oscillate about a centre of rotation in a pendulum movement, the flexible guide comprising at least a first flexible blade connecting the base to the oscillating mass, the first flexible blade comprising at least in part an electrically actuatable piezoelectric material for deforming the first flexible blade and causing the oscillating mass to oscillate.

The method for test the rate of an electronic watch with a time base device (1) comprises three main steps for the test on test equipment. The time base device comprises at least one watch module (2) with a resonator (3) connected to an oscillator of an electronic circuit (4), which is followed by a divider circuit, which is controlled by an inhibition circuit, and which provides a divided timing signal for a motor. In a first step, a measurement is made of the frequency of the oscillator reference signal in at least one measurement period without inhibition. A second step is provided for acquiring the current inhibition value to inhibit a certain number of clock pulses in a subsequently inhibition period and to determine the inhibition value. Finally, a third step is provided for calculating the corresponding rate frequency of the watch.

The method for test the rate of an electronic watch with a time base device (1) comprises three main steps for the test on test equipment. The time base device comprises at least one watch module (2) with a resonator (3) connected to an oscillator of an electronic circuit (4), which is followed by a divider circuit, which is controlled by an inhibition circuit, and which provides a divided timing signal for a motor. In a first step, a measurement is made of the frequency of the oscillator reference signal in at least one measurement period without inhibition. A second step is provided for acquiring the current inhibition value to inhibit a certain number of clock pulses in a subsequently inhibition period and to determine the inhibition value. Finally, a third step is provided for calculating the corresponding rate frequency of the watch.

The invention relates to a piezoelectric resonator, which comprises a base and at least two vibrating arms (3) extending from the base, at least two grooves (4a, 4b) being formed opposite each other on part of the length of the arms and on upper and lower faces of the arms. The depth of the groove on the upper face is less than 30% of the total thickness of each arm and the depth of the groove on the lower face is more than 50% of the total thickness of each arm, or reversely.

The invention relates to a microelectromechanical system (10) comprising a drive module (200) comprising: a fixed drive portion (210), a movable drive portion (220), and a suspension (230),
the movable drive portion (220) being able to be moved relative to the fixed drive portion (210) in a first direction (A), as a result of an electrostatic force, which causes an elastic deformation of the suspension (230), and the movable drive portion (220) being able to be moved relative to the fixed drive portion (210) in a second direction (B), opposite to the first direction (A), as a result of an elastic return force generated by the suspension (230),
the actuator (11) also comprising a stop (24) limiting the movement of the first movable portion (220) in the second direction (B) so that the elastic force generated by the suspension (230) is not cancelled.