Timepiece comprising a mechanical movement wherein the working is regulated by an electromechanical device

Patent metadata

Field	Value
Publication number	US-11599065-B2
Application number	US-201916427405-A
Country	US
Kind code	B2
Filing date	May 31, 2019
Priority date	Jun 19, 2018
Publication date	Mar 7, 2023
Grant date	Mar 7, 2023

Abstract

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.

First claim

The invention claimed is:

1. A timepiece, comprising:
a mechanism for indicating a temporal data item;
a mechanical resonator suitable for having an oscillation movement along a given oscillation axis about a neutral position corresponding to a minimum potential energy state thereof;
a maintenance device of the mechanical resonator, the maintenance device and the mechanical resonator form a mechanical oscillator arranged to pace the working of said mechanism, each oscillation of the mechanical resonator having two successive alternations between two extreme positions, on the oscillation axis, which define the oscillation amplitude of the mechanical oscillator from the neutral position, each alternation having a first half-alternation and a second half-alternation occurring respectively before and after the passage of the mechanical resonator via the neutral position; and
a device for regulating the mean frequency of the mechanical oscillator, the regulation device comprising an auxiliary oscillator, an electromechanical device suitable for stopping during an alternation at least momentarily the oscillation movement of the mechanical resonator in a direction of the alternation, and a regulation circuit arranged to be able to generate a control signal intended for the electromechanical device to activate same,
wherein the regulation device comprises a sensor, arranged to be able to detect the passage of the mechanical resonator via at least a certain given position on the oscillation axis, and a measuring device arranged to be able to measure, on the basis of a detection signal supplied by the sensor, a potential time drift of the mechanical oscillator relative to the auxiliary oscillator,
wherein the measuring device and the regulation circuit are arranged to be able to determine whether the time drift corresponds to at least a certain gain or to at least a certain loss; and
wherein the regulation circuit and the electromechanical device are arranged to be able, when the mechanical resonator oscillates,
a) when the time drift measured corresponds to said at least a certain gain, to stop momentarily, during the first half-alternation of a given alternation, the oscillation movement of the mechanical resonator in the direction of the first half-alternation, so as to prolong the first half-alternation relative to a nominal duration envisaged for each natural half-alternation, and
b) when the time drift measured corresponds to said at least a certain loss, to stop the oscillation movement of the mechanical resonator during the second half-alternation of at least a given alternation so as to prematurely put an end to the second half-alternation, relative to said nominal duration, and to start a next alternation at a time occurring before the nominal duration has been attained since the last passage of the mechanical resonator via the neutral position thereof.

2. The timepiece according to claim 1 , wherein the electromechanical device is formed by an actuator comprising a stopping member defining a mobile banking for a projecting part of the mechanical resonator, the stopping member being arranged mobile between a non-interaction position, where the stopping member is outside an area swept by the projecting part when the mechanical resonator oscillates, and an interaction position where the stopping member is situated partially in the area swept by the projecting part; and
wherein the stopping member may be actuated on command to stop, via the projecting part abutting against the stopping member then placed in the interaction position thereof, the oscillation movement of the mechanical resonator in the direction of the given alternation and selectively in the first half-alternation or the second half-alternation of the given alternation according to whether, respectively, at least a certain gain or at least a certain loss has been detected.

3. The timepiece according to claim 2 , wherein the electromechanical device is arranged such that, when the stopping member is actuated to stop the mechanical resonator in a first half-alternation, the stopping member locks momentarily the mechanical resonator, such that the oscillation movement during the first half-alternation is momentarily interrupted before the oscillation movement is continued after removing the stopping member, and such that, when the stopping member is actuated to stop the mechanical resonator in a second half-alternation, the stopping member prematurely puts an end to the second half-alternation without locking the mechanical resonator by inverting the direction of the oscillation movement of the mechanical resonator, so that the mechanical resonator then directly starts a next alternation, following an instantaneous or quasi-instantaneous stoppage of the mechanical resonator induced by a shock of the projecting part against the stopping member.

4. The timepiece according to claim 3 , wherein, when the stopping member puts an end to a second half-alternation, the stopping member absorbs substantially the kinetic energy of the mechanical resonator such that the next alternation is started with a substantially zero speed.

5. The timepiece according to claim 2 , wherein said stopping member and said projecting part of the mechanical resonator are arranged so as to exhibit therebetween, when the stopping member is placed on command in the interaction position thereof, a substantially elastic shock to stop the oscillation movement of the mechanical resonator in the direction of the given alternation, the stoppage thus induced being instantaneous or quasi-instantaneous and an inversion of the direction of the oscillation movement occurring with a certain kinetic energy restored to the mechanical resonator by the stopping member following the instantaneous or quasi-instantaneous stoppage of the mechanical resonator.

6. The timepiece according to claim 2 , wherein the actuator comprises a piezoelectric element or an electromagnetic system arranged to be able to move on command the stopping member between the interaction and non-interaction positions thereof.

7. The timepiece according to claim 2 , wherein the sensor is arranged to detect at least the passage of the mechanical resonator via the neutral position thereof; and
wherein the regulation circuit is arranged such that, when at least a certain loss is detected, the regulation circuit sends a control signal to the electromechanical device after a detection of a passage of the mechanical resonator via the neutral position thereof so that the electromechanical device actuates the stopping member by placing the stopping member in the interaction position thereof for a duration substantially equal to the nominal duration of a natural half-alternation.

8. The timepiece according to claim 7 , wherein said regulation circuit comprises a time counter and is arranged so as to be able, when at least a certain gain is detected, to reset the time counter after detection of a passage of the mechanical resonator via the neutral position thereof to measure a time delay period before sending the control signal to the electromechanical device so that the electromechanical device actuates the stopping member thereof by placing the stopping member in the interaction position thereof for a predefined or determined duration.

9. The timepiece according to claim 2 , wherein said mechanical resonator is formed by a balance and a balance-spring, the balance bearing said projecting part; and
wherein said stopping member is positioned angularly, relative to the oscillation axis of the balance, so that the stopping member has, when in the interaction position thereof, an angular lag different to zero with the projecting part when the mechanical resonator is in the neu

Assignees

• Swatch Group Res & Dev Ltd

Inventors

• Tombez Lionel

Classifications

• G04C11/00

  Synchronisation of independently-driven clocks · CPC title

• G04B18/04 Primary

  Adjusting the beat of the pendulum, balance, or the like, e.g. putting into beat · CPC title

• G04C13/028

  transmission systems for synchronisation of pendulum of secondary clocks by pendulums of primary clocks · CPC title

• G04C3/042

  using mechanical coupling · CPC title

• G04B17/20 Primary

  Compensation of mechanisms for stabilising frequency · CPC title