A timepiece comprising a mechanical movement and a device for correcting the displayed time

Abstract

The timepiece (2) is formed by a mechanical movement incorporating a mechanical resonator (14). The timepiece comprises a display (12) for displaying the time, a correction device for correcting the displayed time formed by a receiver (30) for receiving an external correction signal provided by an external electronic device 40 (in particular a mobile phone), a damping device (22A) for damping the mechanical resonator, and an electronic control unit (28). The correction device is configured to be able to correct the displayed time as a function of the time error (lag or advance) contained in the external correction signal. For this purpose, the correction device is configured so that the damping device acts on the mechanical resonator during a correction period to change the operation of the drive mechanism of the display in order to correct at least a large portion of the time error of the displayed time.

Description

[Technical Field]

[0001] The present invention generally relates to a timepiece comprising a mechanical movement, a display driven by said mechanical movement for showing the actual time, and a device for correcting said actual time. [Background technology]

[0002] In the field of mechanical watches, the usual way to correct the actual time shown by its indicator is to use a conventional stem-crown, which is generally configured in an extended position to act on a gear set to drive the hour and minute indicators, this drive being thanks to the friction provided in the kinematic chain between these indicators and the escape wheel. Thus, to set a mechanical watch to the actual time, a user or a robot must usually pull out the stem-crown and actuate it, in particular rotating it to move the hour and minute indicators to the desired corresponding positions by visually comparing them with a reference clock such as can be found, for example, in a train station, or with a digital time provided, for example, by a computer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2018 / 177779 [Patent Document 2] Swiss Patent Application Publication No. 711889 Summary of the Invention

[0004] It can therefore be seen that there is a real need in the field of timepieces equipped with mechanical movements for an effective system for correcting the actual time displayed by these timepieces equipped with mechanical movements, in addition to ensuring the precise operation of the mechanical movements. Specifically, the object of the present invention is to enable the accurate setting of the hands of a timepiece, which comprises a mechanical movement driving a time display, and which can preferably be set substantially to the precise actual time provided by an external system (in particular a system connected to an atomic clock) configured to provide the precise actual time, without the need for a user or robot to separately operate the stem-crown or other external control member of the timepiece to set the hands on the display. Within the scope of the present invention, the accuracy of setting the actual time in a timepiece equipped with a mechanical movement does not depend on the visual judgment of the user, which must determine when various associated indicators are in their precise corresponding positions.

[0005] The term "actual time" is generally understood to mean the legal time of a given location where the timepiece and its user are located. Actual time is generally displayed in hours, minutes, and optionally seconds. Actual time may be indicated by a timepiece, particularly a mechanical timepiece, with a certain error. The expression "precise actual time" will be used herein to indicate legal time given with high precision, in particular by / via a GPS system, a telephone network, or a computer connected to an Internet network server that receives actual time from a particularly high-precision clock. This expression also applies to actual time given accurately by an electronic clock or electronic time base incorporated in a device external to the timepiece, which may be periodically synchronized with a high-precision clock that provides legal time. In this context, actual time, in particular as opposed to the actual time displayed by a timepiece, is simply referred to as "time of day."

[0006] In order to meet the aforementioned long-standing needs in the field of horology, the present invention proposes a timepiece comprising: a display for displaying the actual time; a mechanical movement formed by a mechanism for driving the display and a mechanical resonator coupled to the drive mechanism, the vibrations of the mechanical resonator timing the operation of the drive mechanism; a device for correcting the actual time shown by the display; and a device for correcting the actual time displayed is incorporated in the timepiece, - a receiver for receiving an external correction signal for correcting the displayed actual time, - an electronic control unit, and - a device for damping the mechanical resonator, wherein the electronic control unit is configured to process information contained in the external correction signal and to control the damping device as a function of the information. Furthermore, the device for correcting the actual time is configured such that when the external correction signal received by the timepiece requires a correction of the displayed actual time, the damping device is able to act on the mechanical resonator during a correction period to change the operation of the drive mechanism and to perform at least a major part of the correction to the displayed actual time, preferably substantially all of the required correction.

[0007] The term "braking device" is generally understood to mean any device capable of braking and / or stopping a vibrating mechanical resonator and / or keeping such a resonator stopped for a short time (i.e., keeping it disconnected). A braking device may be formed by one or more braking units (one or more actuators). If the braking device is formed by several braking units, in particular by two braking units, each braking unit is selected to act on the mechanical resonator in a specific situation related to the required correction, in particular in situations where the first braking unit corrects the lag and the second braking unit corrects the advance (the second braking unit is advantageously configured to be able to stop and disconnect the resonator for a short time). The phrase "timing the operation of the drive mechanism of the indicator" is understood to mean setting the pace of the movement of the gear set of this mechanism during operation, in particular determining the rotational speed of the gear set and thus of at least one indicator of the indicator. In the following description, when the term "resonator" is used without any specific modifier, it means a mechanical resonator. Vibrating resonator is used to describe a resonator considered to be in its activated state, where the resonator is vibrated and sustained by a mechanical energy source via the escapement.

[0008] In a preferred embodiment, the braking device is formed by an electromechanical actuator configured to be able to apply braking pulses to the mechanical resonator, and the electronic control unit is configured to apply a braking pulse at a frequency F SUP The electronic control unit is configured to provide a first control signal derived from the first periodic digital signal to the braking device during a first correction period to activate the braking device whenever an external correction signal received via the receiver unit corresponds to an indicated time delay to be corrected, so that the braking device generates a first series of periodic braking pulses applied to the mechanical resonator at said frequency F. SUPThe number of periodic braking pulses in the first series, and therefore the duration of the correction period, is determined by the delay to be corrected. SUP the first series of periodic braking pulses at a frequency F SUP is provided, and the damping device is configured to damp the vibration of the mechanical resonator at a correction frequency FS that is greater than the setpoint frequency F0c provided to the mechanical resonator. Cor are synchronized (on average) to

[0009] In an alternative preferred embodiment, in which the timepiece movement comprises an escapement associated with a resonator, the frequency F of the braking pulses of the first series of periodic braking pulses is SUP and duration are selected such that, during said first synchronization phase, each of said first series of braking pulses occurs outside the coupling zone of the oscillating resonator with the escapement.

[0010] In one particular embodiment, the timepiece comprises a device for shutting off the mechanical resonator. Furthermore, the electronic control unit is configured to provide a control signal to the shutoff device when an external correction signal received via the receiver unit corresponds to a displayed time advance to be corrected, the control signal activating the shutoff device so that the shutoff device shuts off the oscillation of the mechanical resonator during a correction period, the correction period being determined by the advance to be corrected so as to terminate the operation of the drive mechanism during the correction period. The shutoff / correction period typically has a duration substantially equal to the corresponding advance to be corrected.

[0011] Generally, the correction of the time displayed by the display is for an error detected in this displayed time by an external electronic device configured to provide an external correction signal to the timepiece. In one particular case, the correction of the displayed time is for seasonal time changes, or even time zone changes.

[0012] The invention further relates to an assembly formed by a timepiece according to the invention and an external device comprising a transmitter for transmitting said external correction signal. a photographic device comprising a photographic sensor formed by an array of photodetectors; an image processing algorithm configured to be able to determine the position of at least one determined hand of the indicator of the timepiece in an image captured by the photographic device; - A time base that can provide accurate actual time; Equipped with.

[0013] In a preferred embodiment, the external device further comprises an algorithm for calculating a time error between first time data and second time data, the first time data being displayed by the display at a given time instant and detected by the external device via a photographic sensor and an image processing algorithm of the external device, and the second time data corresponding to the first time data and being supplied by the time base substantially at said given time instant. If the assembly is intended to correct the calculated time error, an external correction signal supplied by a device external to the timepiece contains information relating to this time error.

[0014] The invention will now be described in more detail using the accompanying drawings, given as examples and in no way as limitations. [Brief explanation of the drawings]

[0015] [Figure 1] 1 shows a partial schematic view of a first embodiment of an assembly according to the invention, comprising a timepiece according to the first embodiment, the timepiece comprising a mechanical movement, a time display, a device for correcting the displayed time, and an external electronic device according to the first embodiment, the external electronic device being configured to be able to communicate with the correction module. [Figure 2] 2 shows a schematic representation of an alternative embodiment of the correction device of the timepiece according to the first embodiment of FIG. 1; [Figure 3]1 shows the change in the oscillation frequency of a mechanical resonator during an advance correction period indicated by the indicator of the considered timer, when the ratio of the correction frequency to the setpoint frequency is relatively equal to the value "1" during correction taking place via a series of periodic braking pulses. [Figure 4] 1 shows the change in the oscillation frequency of a mechanical resonator during a delay correction period indicated by the indicator of the considered timer, when the ratio of the correction frequency to the setpoint frequency is relatively equal to the value "1" during correction taking place via a series of periodic braking pulses. [Figure 5] 1 shows the vibration of the mechanical resonator at the beginning of a delayed correction period accompanied by a series of periodic damping pulses when the ratio between the correction frequency and the setpoint frequency is relatively large, the correction period having an initial transient phase. [Figure 6] 1 shows several oscillation periods of a mechanical resonator during the synchronization phase for two different synchronization frequencies, during which delay compensation is performed using a series of periodic braking pulses. [Figure 7A] 1 shows a number of curves of the maximum relative synchronous frequency as a function of the amplitude of the free vibration of the resonator and the quality factor of the resonator, for a damping frequency corresponding to one damping pulse per half period of vibration of the mechanical resonator. [Figure 7B] 1 shows a number of curves of the maximum relative synchronous frequency as a function of the amplitude of the free vibration of the resonator and the quality factor of the resonator, for a damping frequency corresponding to one damping pulse per vibration period of the mechanical resonator. [Figure 8] 10 is a graph showing an approximate range of expected correction frequencies for correcting lag in a time indicator using short periodic braking pulses as a function of multiple braking frequencies selected for the braking pulses for a given setpoint frequency. [Figure 9] 10 is a graph showing an approximate range of expected correction frequencies for correcting advance in a time indicator using short periodic braking pulses as a function of multiple braking frequencies selected for the braking pulses for a given setpoint frequency. [Figure 10]2 shows part of a second embodiment of a timepiece according to the invention; [Figure 11] 3 shows part of a third embodiment of a timepiece according to the invention; [Figure 12] 4 shows a schematic representation of a fourth embodiment of a timepiece according to the invention; [Figure 13] 1 partially shows a second embodiment of an assembly according to the invention, the assembly comprising a timepiece according to the invention and an external electronic device according to the second embodiment, which serves as a housing and a charging station for the timepiece. [Figure 14] 10 shows a schematic configuration of electronic elements and functional units in an external electronic device of a second embodiment. [Figure 15] 5 shows diagrammatically a fifth embodiment of a timepiece according to the invention, which can form an assembly according to the second embodiment; [Figure 16] 10 shows a partial schematic view of a sixth embodiment of a timepiece according to the invention; [Figure 17] 17 shows the vibration of the mechanical resonator during the delay correction period for two alternative embodiments of the damping device of the timepiece of FIG. 16; [Figure 18] 17 shows the vibration of the mechanical resonator during the delay correction period for two alternative embodiments of the damping device of the timepiece of FIG. 16; DETAILED DESCRIPTION OF THE INVENTION

[0016] With reference to Figures 1 and 2, the following description describes a first embodiment of a timepiece according to the invention and a first embodiment of an assembly according to the invention comprising a timepiece according to the invention and an external electronic device formed by a mobile phone.

[0017] The timepiece 2 comprises a mechanical movement 4, an analog time display 12, a drive mechanism 10 for driving the display, and a device 6 for correcting the time indicated by the display. The mechanical movement comprises a barrel 8 forming a source of mechanical energy for the drive mechanism 10 formed by a gear train 11 kinematically linked to the display, a mechanical resonator 14 formed by a balance 16 associated with a balance spring 15, and an escapement 18 connecting the resonator to the drive mechanism, the oscillations of which time the operation of the drive mechanism. The analog display 12 is formed by a dial 32 with indices 36 forming a scale for displaying the actual time, and hands 34 with hour, minute, and second hands. The hands have different shapes, in particular different lengths and / or widths. Preferably, the indices are configured so that the position "12 o'clock" in the case of a 12-hour cycle (or "24 o'clock" in the case of a 24-hour cycle) is visually recognizable. In the illustrated case, the "12 o'clock" angular position is defined by two parallel, substantially radial bars, while the angular positions at other times are defined by a single bar.

[0018] Various alternative embodiments can be provided to enable determination of at least one angular position of the indicator corresponding to the number of minutes and / or seconds determined on a scale provided for displaying the minutes and / or seconds. It should be noted that the scale is not necessarily visible. More specifically, for example, it is known that there is a 12-hour cycle and that the "12 o'clock" angular position is provided on a given, identifiable timepiece axis. It is sufficient for a visible mark on the display side to identify the 12 o'clock angular position on the given axis, and thus to identify any other angular positions corresponding to any hour, any minute, and / or any second. For example, the dial may have a pattern that allows the orientation of the dial to be determined, or may include additional symbols defining the determined angular marks corresponding to specific positions on the provided scale. Such additional symbols could also be placed on the edge surrounding the dial or bezel of the watch case in which the mechanical movement 4 is incorporated. It should be noted that the angular marks may simply be provided by the shape of the case, which defines the determined axis, or by the winding button, which can be visually recognized. It should be noted that the present invention is also not limited to analogue displays of real time, but may also relate to other displays that display real time, for example displays with a "jumping hour change" and / or in particular a "jumping minute change". The display is therefore not limited to systems with hands that advance in a substantially continuous manner. The present invention may therefore also be applied in particular to systems with discs or rings, and in particular to displays provided via at least one opening in the dial.

[0019] The correction device 6 receives an external correction signal S which corrects the time displayed by the display 12. Ext and an electronic control unit 28 for displaying the time, the electronic control unit 28 being adapted to receive an external correction signal S Ext and in response thereto, generating at least one internal correction signal related to a correction to the displayed time, the at least one internal correction signal being in turn connected to an external correction signal S ExtThe time indicated by the time display of the timepiece is determined by the external correction signal S received by the timepiece 2, i.e., by the information contained in this external correction signal. Ext , and is configured to enable the displayed time to be corrected as a function of . In order to correct the displayed time, the correction device generally comprises a device for damping the mechanical resonator. In a main alternative embodiment, the damping device is formed by an electromechanical actuator, for example an actuator 22A of the piezoelectric type. Furthermore, the damping device is controlled by an electronic control unit 28, which transmits a control signal S to control the power supply circuit of the damping device so as to manage the timing of the application of the mechanical damping force to the mechanical resonator 14. Cmd to the braking device. Generally, the correction device transmits an external correction signal S received by the timer. Ext However, whenever a correction of the displayed time is required, the braking device is configured to act on the mechanical resonator 14 during the correction period to change the operation of the drive mechanism 10 so as to correct at least most of the displayed time.

[0020] In the alternative embodiment shown, the actuator 22A comprises a damping member formed by a flexible strip 24, which has two piezoelectric layers on two opposing surfaces (perpendicular to the plane of FIG. 1 ), each covered with a metal layer to form an electrode. The piezoelectric actuator comprises a power supply circuit 26, allowing a specific voltage to be applied between the two electrodes to apply an electric field through the two piezoelectric layers. The piezoelectric layers are configured, upon application of a voltage between the two electrodes, to bend the strip 24 toward the outer edge 20 of the balance 14, thereby forcing the end of the strip forming the moving damping pad against the outer circular surface of the outer edge and thus applying a mechanical damping force to the mechanical resonator. It should be noted that the voltage can be varied to vary the mechanical damping force, and therefore the mechanical damping torque, applied to the balance. Regarding damping devices, reference can be made to WO 2018 / 177779 for various embodiments of such damping devices in mechanical timepiece movements. In a particular alternative embodiment, the braking device is formed by a strip actuated by a magnet coil system. In another particular alternative embodiment, the balance comprises a central staff defining or holding the part, in addition to the outer edge of the balance, for example a disk, which defines a circular braking surface. In the above case, the pads of the braking element are configured to exert pressure against this circular braking surface upon the momentary application of a mechanical braking force.

[0021] The receiver unit 30 is preferably a contactless receiver, for example a sensor for optical signals coded according to a given communication protocol, a "Bluetooth" receiver (preferably "Bluetooth Low Energy": BLE), or a receiver for short-range wireless communication known as NFC. It should be noted that in the latter two cases there is in fact a communication unit that allows sending and receiving signals according to a predefined standard. The receiver unit 30 receives an external correction signal S Ext is demodulated and the demodulated signal S Ext The digital correction signal S corresponding to Corto the electronic control unit 28.

[0022] One preferred alternative of the first embodiment of the assembly according to the invention comprises a timepiece according to the invention and a mobile phone 40, in which at least one time correction application for implementing the invention is installed, which in particular detects the error in the time displayed by the display of the timepiece and generates a corresponding external correction signal S Ext The mobile phone has its own resources used by the time correction application, in particular an energy source 42, a time base 48 that provides the precise actual time, and a photographic device with a photographic sensor formed by an array of photodetectors. The time base may be formed by an electronic clock that is periodically synchronized with the precise actual time provided by the telephone network or a WIFI and / or GPS receiver. The time base therefore provides a reference time that is quite accurate and that can be synchronized to, for example, the electronic clock and indicate the precise actual time at the mobile phone and the mobile phone user's location. The photographic device 44 has a sensor formed by a pixel array that takes a precise image of the analog display 12.

[0023] The time correction application installed in the mobile phone includes an image processing algorithm 46, or the application is configured to enable such an algorithm for a specific image processing application installed on the mobile phone or on a server accessible by the mobile phone, particularly via the Internet. The image processing algorithm is configured to determine the position of at least one determined hand of the analog display 12 in an image captured by the photographic device 44. That is, the position of this hand is relative to a scale provided on the display, which can be reduced to a single visual mark, as shown above, to determine the specific position of a virtual scale. In the case of a display with two hands (hour and minute hands), the angular position of at least the minute hand is determined relative to a mark on the dial 32 or another part of the timepiece visible from the display side, making it possible to determine the displayed minutes relative to the minute scale (whether visible or not). In the case of a display with three hands (hour, minute, and second hands), the angular positions of at least the minute and second hands are determined. See also the text above for various alternative embodiments that may be provided for determining the angular position of at least one of the displays.

[0024] In this case, the time correction application comprises an algorithm for calculating a time error between first time data displayed by the display at a given time instant and detected by an external device, in particular the mobile phone 40, via its photo sensor and image processing algorithms, and second time data corresponding to the first time data and supplied by the time base 48 at said given time instant. As mentioned above, the first time data may be displayed minutes, displayed minutes and seconds, or displayed actual time (hours, minutes and seconds).

[0025] Finally, the mobile phone 40 receives an external correction signal S ExtThe transmitter unit (transmitter) is of the same type as the receiver unit (of the receiver) of the timepiece, in particular of optical type (photodiode) or wireless type (for example BLE or NFC communication unit). The time correction application is carried out by transmitting the results provided by the algorithm for calculating the time error to an external correction signal S Ext The portable device 50 includes a function for encoding the time error into a format specific to the transmitter unit 52 for transmission. Thus, if it is intended to correct a detected time error, the external correction signal provided by a device external to the timepiece includes information related to this time error. Preferably, the transmitted information is the detected time error in the most accurate units allowed by the time display, typically seconds or tenths of seconds. It will be appreciated that the decision whether to correct the display can be made by an application in the portable device or by an electronic control unit in the timepiece. Clearly, if the detected error is zero, no correction is necessary. If the detected error is non-zero but insignificant, e.g., less than 5 seconds, in an alternative embodiment, it can be determined that this error does not require correction. In other words, in at least one operating mode, a range of values ​​can be defined for the detected time error for which no correction to the display is provided.

[0026] In another alternative embodiment, the algorithm for calculating the time error described above is provided to be built into the timer. In such a case, an external correction signal S ExtThe time data includes first and second time data, which are then processed by an algorithm for calculating a time error, which is incorporated into an electronic control unit located within the timepiece. In an embodiment in which the timepiece includes an internal electronic clock, the time based on the mobile phone may be further transmitted to the timepiece as further information, particularly in the case of a "fitness" type electronic module. More specifically, the second time data relates to the instant in time when the image was captured and does not exactly correspond to the instant when the external correction signal was transmitted. For this reason, supplementary data related to the third time data is advantageous when it is desirable to provide the internal electronic clock of the timepiece with accurate time for further functions.

[0027] FIG. 2 shows a device for correcting a timepiece according to a first embodiment. The receiver unit 30A is formed by a sensor for detecting optical signals. This optical sensor comprises at least one element of the phototransistor type. In an alternative embodiment, the optical sensor is part of a solar cell or is formed by a solar cell, which forms an energy harvester 54 and is used to power an electrical accumulator 56. In another alternative embodiment, the optical sensor 30A is a separate element from the energy harvester 54, which serves as an energy source for the power supply circuit 58 of the correction device. The energy harvester can be formed by various types of devices known to those skilled in the art, for example, by a magnetic, optical, or thermal energy harvester. In an alternative embodiment, a magnetic energy harvester is configured to receive energy from an external magnetic source, allowing the electrical accumulator to be recharged without electrical contact. In another advantageous alternative embodiment, the energy harvester is formed by a magnet-coil system and is capable of harvesting small amounts of energy from the vibrations of the mechanical resonator of the timepiece and, therefore, from the vibrations of the barrel that sustains this vibration. In the alternative embodiment described above, at least one magnet is arranged on the vibrating element of the resonator or on the support of the resonator, and at least one coil is arranged on said support or on said vibrating element, respectively, so that a large portion of the magnetic flux generated by the magnet passes through the coil when the resonator vibrates within its usable operating range. Preferably, the magnet-coil coupling is provided around the neutral (rest position) position of the resonator. In another alternative embodiment, in which the mechanical movement is an automatic movement, a vibrating weight is used to drive a micro-generator to generate electricity, which is stored in an accumulator. The energy harvester can also be hybrid, i.e. formed by several different units, in particular of the wireless / contactless type, which are intended to harvest different energies from different energy sources and convert these different energies into electrical energy.

[0028] The electronic control unit 28A controls the device 22 for braking the resonator 14, in particular an electromechanical actuator 22A shown diagrammatically in Figure 1. Other types of actuators may be provided which allow a braking force to be applied to the mechanical resonator only for a short period of time. Optionally, the electronic control unit comprises a circuit 68 for detecting the level of available electrical energy, which detects the signal S to the control logic circuit 60. NE to provide information about the level of electrical energy available, so that the logic circuit knows whether the correction module has enough energy before starting the operation to correct the displayed time. If not, various options are possible: 1) The timepiece has a transmitter that allows the user to be notified directly, for example via an optical or acoustic signal generated by the transmitter, that the accumulator must be recharged to allow a full correction of the displayed time. As long as the electrical energy level is insufficient to complete the correction operation, the timepiece will not perform any correction operation. 2) The timepiece has a transmitter, in particular a BLE or NFC communication unit or an optical transmitter consisting of at least one light-emitting diode, making it possible to inform the mobile phone 40 that the accumulator needs to be recharged in order to fully correct the displayed time. The mobile phone can thus show the information to the user on its electronic display. Alternatively, the timepiece does not perform any correction operation as long as the electrical energy level is insufficient to complete the correction operation. According to an advantageous alternative embodiment, the mobile phone directly activates the recharge function to recharge the electrical accumulator 56 via the energy harvester 54 or via another energy harvesting device specialized in transferring energy from the mobile phone, for example by magnetic induction. 3) The timepiece only performs a partial correction of the displayed time using the energy available in the accumulator 56 and preferably notifies the mobile phone via a transmitter located within the timepiece that only a partial correction has been performed and that there is optionally a remaining error which the logic circuit 60 can calculate. 4) The timer does not perform any corrective actions and does not transmit any information (simple alternative with a "dumb" timer).

[0029] In the absence of an electrical energy management system as indicated above, the timer can initiate the necessary corrective action if the available voltage is sufficient, and can perform this corrective action as long as the voltage provided by the power supply circuit 58 is sufficient. In an advantageous alternative embodiment, in order to conserve the electrical energy available in the accumulator 56, the correction device is placed in a standby mode when no action is scheduled to correct the displayed time. If desired, various parts of the correction module can be activated for different periods of time. Similarly, see below for the management of the power supply of the correction device according to the invention within the scope of alternative embodiments.

[0030] The electronic control unit 28A incorporated in the first embodiment of the timepiece 2 receives an external correction signal S Ext Receiver 30A receives a digital correction signal S Cor and a control logic circuit 60 receiving a given frequency F SUP and a generating device 62 for generating a periodic digital signal having a frequency F SUP (Also called the "generator" in Err However, the actual time delay (negative T Err ) or leading (positive T Err ) the control logic circuit 60 sends two control signals S1 to a frequency generator 62 and a timer 63, respectively. R and S2 R, or one control signal S sent to the timer 70 A The timers 63 and 70 are programmable and generate the intended correction period, i.e., the period PR Cor , and the period PA for correcting the advance Cor By definition, a lead corresponds to a positive error and a lag corresponds to a negative error. As mentioned above, the logic circuit measures the time error T Err In the second case, the logic circuit receives either the time displayed by the timer at a given time instant (preferred alternative embodiment), or the corresponding accurate actual time provided by the time base of an external electronic device. Err Calculate itself.

[0031] First, the configuration of the electronic control unit 28A for correcting the delay detected in the time display will be described, and then only the configuration of this unit for correcting the advance will be described.

[0032] In the case of a negative time error corresponding to a lag, according to the first lag correction mode, the invention generates a series of periodic braking pulses with a frequency F SUP These periodic damping pulses are applied to the vibrating resonator by the damping device 22, in particular by the actuator 22A. For this purpose, the control logic circuit 60 provides a signal S1 R and starts the frequency generator 62 via Cor , starting a timer 63 that counts up to or counts down from a time interval corresponding to , the duration (its value) of which is determined by logic circuitry (by definition, the expression "timer" encompasses timers that count up to a given time interval as well as timers that count down from this given time interval which is initially entered into the timer).

[0033] In the alternative embodiment shown, when the frequency generator is activated, it generates a periodic digital signal SFS frequency F SUP (the timer has a value Tp corresponding to the duration selected for the periodic braking pulse). The outputs of timers 63 and 64 are provided to an "AND" logic gate 65 which determines the intended correction period PR Cor , via an "OR" logic gate 66, or by a periodic start signal S C1 to the braking device via any other switching circuit that allows the periodic activation signal S C1 to periodically activate the braking device 22. C1 is the control signal S when correcting for a detected delay in the time indicated by the timer. Cmd Therefore, the braking device forms a correction period PR Cor During this time, a periodic braking pulse is applied at a frequency of F SUP , the duration (value) of which depends on the delay to be corrected. As a general rule, the braking pulses have a dissipative nature, since part of the energy of the vibrating resonator is dissipated during these braking pulses. In the main embodiment, as explained above with reference to FIG. 1 in the description of the timepiece 2, the mechanical braking torque is applied substantially by friction, in particular by a mechanical braking member applying a constant pressure on a braking surface of the resonator, preferably a circular braking surface.

[0034] Preferably, for the alternative embodiment shown in Figure 1, the system formed by the mechanical resonator and by the device for damping this resonator is configured to enable the damping device to initiate a mechanical damping pulse at substantially any instant in the natural vibration period of the vibrating resonator within the usable operating range of the vibrating resonator, in other words, one of the periodic damping pulses, and in particular the first damping pulse occurring during a correction period, can begin at substantially any angular position of the vibrating resonator.

[0035] According to the disclosure of WO 2018 / 177779 already cited above, the average frequency of the vibrating resonator is determined by applying periodic damping pulses to the resonator, advantageously at a setpoint frequency F0 C 2 times the value divided by a positive integer N, that is, F FR =2·F0 C / N, the corresponding damping frequency F FR Once a positive integer N is given, the damping frequency F FR is proportional to the setpoint frequency F0c for the mechanical resonator and depends only on this setpoint frequency. If the braking torque applied by the braking pulses and the duration of these braking pulses are chosen so that during the synchronization phase, the braking pulses occur at the moment when the mechanical resonator passes the farthest point in its oscillation, i.e., a reversal of the direction of the oscillatory motion occurs during or at the end of each braking pulse, then the braking frequency F FR WO 2018 / 177779 discloses that after a transient phase, which occurs when a braking device that applies periodic braking pulses at t begins to activate, a synchronization phase is established, during which the vibrations of the mechanical resonator are synchronized on average to the setpoint frequency F0c. The latter solution occurs in particularly advantageous cases where reliability is higher, in which the mechanical resonator is stopped by each braking pulse and then remains blocked by the braking device until this braking pulse ends.

[0036] Although of lesser interest, Patent Publication No. 2018 / 177779 also proposes a damping frequency F that is greater than twice the setpoint frequency (2F0). FR In particular, we show that synchronization can be obtained for values ​​equal to M·F0, where M is an integer greater than 2 (M>2). F FR In an alternative embodiment where F = 4·F, the system simply loses energy and has no effect during the synchronization phase, since one out of two pulses occurs at the neutral point of the resonator, which is a disadvantage. FRFor , during the synchronization phase, pulse pairs that do not occur at the furthest positions cancel each other's effects. Therefore, these are understood to be theoretical scenarios that are not of great practical interest. It should be noted that other damping frequencies can lead to the synchronization of the resonator to the setpoint frequency, but the conditions for implementing the adjustment method are much more cumbersome and difficult to implement.

[0037] Within the scope of the development at the origin of the present invention, it was emphasized that the remarkable phenomenon disclosed in WO 2018 / 177779 can be used not only to continuously synchronize a resonator to its setpoint frequency, but also to vary the oscillation frequency of the resonator in a determined manner in two frequency ranges located respectively below and above the setpoint frequency: a determined mean frequency can be imposed on a mechanical resonator, this determined mean frequency being different from the setpoint frequency, either greater than or less than it, and by applying periodic braking pulses, this resonator can be synchronized to a frequency different from but sufficiently close to the setpoint frequency, allowing a synchronization phase to be established between the oscillating resonator and a braking device, generating braking pulses at a frequency selected for this purpose, while maintaining the oscillating resonator in a functional range in order to time the operation of a timer. The present invention makes use of this remarkable discovery to propose correcting the time displayed by a timepiece by modifying the operation of the mechanical timepiece movement considered, that is to say by varying, during a given correction period, the frequency of the resonator that times the operation of the mechanism that drives the display of the timepiece in question.

[0038] In particular, a first embodiment of the electronic control unit described herein provides for correcting the detected delay at the indicated time according to a first delay correction mode, in which the correction period PR Cor During this time, the vibrating resonator operates at a correction frequency FS, which is greater than the setpoint frequency F0c. Cor Within the scope of the development at the origin of the invention, as in the case of synchronization to the setpoint frequency, a given correction frequency FCor For damping frequency F Bra to the following formula: F Bra =2 F Cor / N (N is a positive integer) It has been shown that choosing to satisfy ρ=ρ(σ) gives the best results for correction frequencies greater than or less than the setpoint frequency.

[0039] Therefore, the periodic braking pulses have a braking frequency F Bra and the damping frequency is advantageously the correction frequency F Cor This equation corresponds to twice the setpoint frequency F, preferably divided by a sufficiently small positive integer N. Cor =FS Cor and a correction frequency F that is smaller than the setpoint frequency Cor =FI Cor (first advance correction mode, which will occur in the following further embodiments of the timepiece according to the invention). Thus, once a positive integer N is selected, the damping frequency F Bra is the correction frequency F Cor and depends only on this correction frequency. The term "synchronization to a given frequency" is understood to mean synchronization on average with respect to this given frequency. This definition is important for numbers N greater than 2. For example, if N=6, the time difference caused by each damping pulse of the resonator oscillations results in only one of the three oscillations undergoing a change in its duration relative to the setpoint period T0c=1 / F0c (and therefore relative to the natural / free oscillation period T0=1 / F0).

[0040] As with synchronization to the setpoint frequency, in certain circumstances it is possible to use other damping frequencies to obtain synchronization to the desired correction frequency, but the damping frequency F Bra =2 F Cor / N is selected in a more efficient and stable manner to obtain the frequency F CorIt should be noted that this allows obtaining synchronization to F. In general, the mathematical equation that expresses the relationship between the damping frequency and the correction frequency is F Bra =(p / q) F Cor where p and q are two positive integers, advantageously the number q being greater than the number p. Those skilled in the art can experimentally create a list of suitable fractional numbers p / q and which conditions (in particular which braking torques) are suitable.

[0041] It is understood that the braking pulses can be applied with a constant or non-constant couple (e.g., substantially Gaussian or sinusoidal). The term "braking pulse" refers to the application of a momentary couple to the resonator, which brakes the vibrating member (balance) of the resonator, i.e., opposes the oscillatory motion of this vibrating member. In the case of a variable torque, the pulse duration is generally defined as the portion of this pulse that has a large couple to brake the resonator, specifically the portion where the couple is greater than half of the maximum value. It should be noted that the braking pulses can exhibit large variations. They may even vary continuously and form a series of shorter pulses. In general, the duration of each braking pulse is provided to be less than half the setpoint period T0c for the resonator, but is advantageously less than one-quarter of the setpoint period, preferably less than T0c / 8.

[0042] 3 and 4 show the frequency F for a mechanical resonator with a setpoint frequency F = 4 Hz and vibration 72, respectively, when the natural frequency is F = 4.0005 Hz. INF =2 FI Cor , F.I. Cor A first series of periodic damping pulses 74 applied to the resonator at =0.99975·F0c=3.999Hz and a frequency F SUP =2·FS Cor , F.S. Cor3 and 4 show the change in the oscillation frequency of the resonator during a correction period, when the braking pulses are applied at a frequency F INF or F SUP The curve 78 shows the change to the vibration frequency of the mechanical resonator during the first series 74 of periodic damping pulses to correct the detected lead at the indicated time, the damping frequency F INF As a result, the correction frequency FI given by the synchronous frequency Cor is obtained, which is less than the setpoint frequency F0c (first lead correction mode). Curve 80 shows the change to the vibration frequency of the mechanical resonator during the second series 76 of periodic damping pulses to correct the detected lag at the indicated time, damping frequency F SUP As a result, the correction frequency FS given by the synchronous frequency Cor is obtained, which is greater than the setpoint frequency (first lag correction mode).

[0043] The very short correction periods in FIGS. 3 and 4 are intended to show the entire correction period, clearly showing the resonator oscillation and periodic braking pulses in the graphs showing the angular position of the resonator as a function of time. More specifically, the expected correction is relatively small, at a few seconds, and in fact less than one second. Therefore, for the correction frequencies selected in FIGS. 3 and 4, the correction is very small. Therefore, since the natural frequency (natural / free frequency) of the vibrating resonator corresponds to a daily deviation of approximately 10 seconds (gain or loss) per day, which is within the standard range for mechanical watches, the correction frequency is provided for illustrative purposes only and is much closer to the setpoint frequency than the correction frequencies typically provided to implement the first advance or loss correction modes. In conclusion, FIGS. 3 and 4 are provided only schematically to illustrate the behavior of a vibrating resonator as a whole when subjected to a series of periodic braking pulses at a correction frequency close to but different from the setpoint frequency, and when the natural frequency causes a typical time drift. A more detailed and precise discussion of expected correction frequencies will be given below.

[0044] In the two graphs showing the frequency curves 78 and 80, the transient phase PH Tr After the frequency change, the transient phase is followed by a synchronous phase PH Syn between them, with frequency FI Cor or FS Cor In the two cases shown, the transient phase PH TrThe transient phase is relatively short (less than 2 seconds), and the frequency change occurs in the direction of the desired correction frequency. In the two cases shown, the average correction per unit time during the transient phase is approximately equal to the average correction occurring during the synchronization phase. However, it should be noted that the transient phase could be longer, e.g., 3-10 seconds, and the frequency change during the transient phase would possibly fluctuate, thereby making the average correction variable and undetermined, but remaining small in practice. See Figures 9-11 of WO 2018 / 177779, where the transient phase for synchronizing the resonator from its natural frequency to a nearby but different setpoint frequency F0c is longer. Figure 10 of this document shows that when the setpoint frequency is greater than the natural frequency of the resonator, the vibration frequency initially decreases at the beginning of the transient phase, then increases, eventually exceeding the natural frequency and stabilizing at the setpoint frequency.

[0045] The duration of the transient phase and the change in frequency during this transient phase depend on various factors, in particular the braking torque, the duration of the pulse, the initial amplitude of the vibration, and the moment in the vibration cycle when the first braking pulse is applied. Therefore, it is difficult to control the time deviation from the setpoint frequency that results from the transient phase. For example, F Cor = 1.05 · F0c = 4.2 Hz, and assuming that the transient phase lasts a maximum of 10 seconds and that the average frequency during this transient phase is equal to F0c, then F Cor The absolute time deviation for the correction period PR is at most 0.5 seconds. This uncertainty therefore generates a small error in the corrections made during the correction period, but this error is not negligible. To prevent such errors, a solution is described below. In a first embodiment of the electronic control unit, the (duration of) the correction period PR Cor is the time error T ErrBy defining this correction period as the period during which a series of periodic braking pulses at the intended braking frequency are applied to the resonator, and by applying the assumption that the oscillation frequency during the correction period is that of the synchronous frequency, there is therefore an expected small error in the correction obtained, if the correction period is determined on the basis of .times. ...

[0046] The synchronization frequency determines the correction frequency. By definition, the correction frequency F Cor is equal to the synchronization frequency. It can be seen that in the synchronization phase of the correction period, the duration of the braking pulses must be sufficient to bring the resonator to a stop during or at the end of each braking pulse (the passage of the furthest angular position that defines its instantaneous amplitude). In the case of a synchronization frequency greater than the setpoint frequency for correcting lag, the time interval during which the resonator remains stopped between braking pulses reduces the correction possible per unit time, so it is preferable to limit this time interval, taking into account a certain safety margin, thereby shortening the correction period thanks to the larger synchronization frequency. It should be noted that the frequency of the braking pulses, the maintenance energy supplied to the resonator at the time of each half-period of its oscillation, and the value of the braking torque occur in the time interval required to bring the vibrating resonator to a stop. Those skilled in the art will know how to determine the braking torque and duration of the braking pulses, in particular experimentally or by simulation, in order to optimize the braking system for a given braking frequency and the resulting correction frequency. For a setpoint frequency of 2 Hz to 10 Hz, a braking torque in the range of 0.5 μNm to 50 μNm and a braking pulse in the range of 2 ms to 10 ms are usually deemed suitable as advantageous correction frequencies for practical use (these value ranges are given for illustrative purposes and are not limiting).

[0047] Based on the above assumption, i.e., the synchronization frequency is Cor When applied over the entire time period, the value of the correction period provided is the time error T Err , setpoint frequency F0c, and correction frequency FCor Since the synchronization frequency determines the correction frequency, the value of the correction period provided also determines the time error T to be corrected. Err , setpoint frequency F0c, and damping frequency F Bra By definition, an advance in the displayed time corresponds to a positive error, while a delay corresponds to a negative error. The following formula was derived to determine the value of the correction period: P Cor =T Err F0c / (F0c-F Cor )=2T Err ·F0c / (2F0c-N·F Bra )

[0048] In the first delay correction mode (negative error), the correction frequency F Cor =FS Cor is P Cor is greater than F0c so that is positive. In such a case, the damping frequency F Bra =F SUP Therefore, we have the following formula: PR Cor =T Err F0c / (F0c-FS Cor )=2T Err ·F0c / (2F0c-N·F SUP )

[0049] In the first lead correction mode (positive error), the correction frequency F Cor =FI Cor is P Cor is positive. In such a case, the damping frequency F Bra =F INF Therefore, we have the following formula: PA Cor =T Err F0c / (F0c-FI Cor )=2T Err ·F0c / (2F0c-N·F INF )

[0050] In an alternative embodiment, the external electronic device (mobile phone 40) has in memory or receives from the considered timer the setpoint frequency for the mechanical resonator of this timer, and (optionally as a function of the value range of the delay) the higher frequency to be supplied to correct this delay. Thus, in this alternative embodiment, the time correction application implemented in the external electronic device calculates the value of the correction period PR Cor and external correction signal S Ext In this alternative embodiment, the electronic control unit of the timer may communicate this information to the timer via Err It does not require resources to calculate the value of the correction period based on

[0051] Following the general explanation regarding the correction of the operation of a mechanical timepiece, in which the correction is obtained by a series of periodic damping pulses applied to its resonator, we can now return to the first embodiment of the timepiece according to the invention. The electronic control unit 28A (FIG. 2) receives an external correction signal S received by the receiver unit of the timepiece 2. Ext corresponds to the indicated time delay to be corrected, the periodic digital signal S provided by the frequency generator 62 FS The control signal S derived from C1 , correction period PR Cor to the braking device 22 during braking, thereby causing the braking device to generate a series of periodic braking pulses at a frequency F SUP The correction period (duration) is determined by the delay to be corrected, and therefore the number of periodic braking pulses in the series of periodic braking pulses is also determined by the delay to be corrected. SUP The frequency F is set to F, such that each of a series of periodic braking pulses at F can be a first synchronization phase during the corresponding correction period, causing the oscillation of the resonator to synchronize (by definition, "synchronize on average") to a correction frequency F, which is greater than the setpoint frequency F provided to the mechanical resonator. SUP are provided to form a braking device.

[0052] 5-10, the following paragraphs will discuss the braking pulse, specifically the braking frequency F Bra and the corresponding correction frequency F Cor We present some observations relating to the first lag correction mode, which are advantageously taken into account for a preferred alternative embodiment of the first lag correction mode, and also for a preferred alternative embodiment of the first lead correction mode, which will be implemented in the embodiments described below, in which the detected lead at the indicated time is detected at a frequency F already defined above. INF The braking frequency F is corrected by a series of braking pulses at 100 Hz, resulting in a correction frequency FI, also defined above, which is less than the setpoint frequency F0c. Cor It is intended to be.

[0053] FIG. 5 shows the first part of the correction period, with the correction frequency FS Cor = 3.5 Hz and the set point frequency F0c = 3.0 Hz (which is substantially equal to the natural frequency of the resonator when vibrating freely, as shown by vibration 82), i.e., the ratio RS = FS Cor / F0c=3.5 / 3.0=1.167. Damping frequency F Bra =F SUP =2·FS Cor = 7.0 Hz (for N = 1) and a braking pulse 84 with sufficient braking couple is applied to the mechanical resonator to generate a transient phase PH Tr , when the amplitude of the vibration 86 of the vibrating resonator is sufficiently reduced and can finally stop during each braking pulse, the corresponding correction frequency, i.e., FS Cor = 3.5 Hz can be imposed on this resonator relatively quickly. In the given example, the desired synchronization is obtained after just 1 second, but the phase PH St is the synchronization phase PH Syn In the case shown, the amplitude increases again during the stabilization phase and finally stabilizes at an amplitude corresponding to about 1 / 3 of the initial amplitude of the free resonator.

[0054] A demonstrator (prototype of a timepiece according to the invention) was constructed for the case shown in Figure 5. A periodic damping pulse with a frequency F SUP = 7.0 Hz, a 7-hour advance was obtained on the timepiece's display with great precision for a 6-hour correction period. Thus, the actual time was exactly 1 hour "advanced" for 6 hours. Such a result paves the way for methods of correcting the time shown by the display that are different from simply correcting the display's time drift, which is the result of the inaccuracy of a freely running (i.e., no damping pulses present) resonator. Thus, as will be seen from other embodiments described below, the present invention makes it possible to correct for the 1-hour jump that occurs with seasonal time changes (particularly for changes from standard time to daylight saving time, where the legal time is advanced). Corrections for time zone changes that may occur during travel can also be taken into account.

[0055] FIG. 6 shows the free oscillation 82A of the mechanical resonator and the first oscillation 86A of this resonator during the synchronization phase of the correction period, with the correction frequency FS Cor and the setpoint frequency F0c is relatively small (i.e., relatively close to "1"), and a second oscillation 86B of this resonator in the synchronization phase of the correction period, Cor and a second oscillation 86B, where the ratio RS between the setpoint frequency F0c and the setpoint frequency F0c is relatively large (i.e., relatively far from "1"). The first oscillation 86A results from a series of periodic braking pulses 84A of relatively low intensity, occurring once per oscillation period (which is the case for N=2, F SUP =FS Cor , the second oscillation 86B, however, results from a series of relatively high intensity periodic braking pulses 84B, occurring once every half period of oscillation (this corresponds to the case where N=1, i.e., F SUP =2·FS Cor (This corresponds to the case of

[0056] By appropriately selecting the braking torque and braking frequency, the correction frequency is determined by the set point frequency F0c and a specific higher frequency FSC to correct the time delay shown.max and can be varied continuously between the setpoint frequency F0c and a specific lower frequency FIC to compensate for the advancement of the displayed time. max It can be seen that the higher the frequency, the more FSC max and lower frequency FIC max are not values ​​that can be easily calculated theoretically; they must be determined in practice for each timer. It will be appreciated that this information, although of interest, is not essential. What is important is that the braking frequency is selected and the available braking torque is adequate to cause a synchronization phase to occur, preferably very quickly, during each correction period, during which the mechanical resonator can oscillate at the correction frequency provided by the mathematical equations mentioned above, without its oscillations ceasing (i.e. the resonator must not stop so that it cannot be restarted from a stopped position, which would stop the display drive mechanism).

[0057] Figure 6 shows the safety angle θ Sec , in absolute value form, below which the mechanical resonator is prevented from shutting down (i.e., -θ Sec ~θ Sec ), above which the amplitude in absolute value must therefore be maintained during the synchronization phase, at least after the stabilization phase. Sec is the angle θ ZI (see FIG. 10) or preferably an angle θ ZI is larger than the angle θ ZI corresponds to the coupling angle between the resonator and its associated escapement on either side of the resonator's neutral position and is determined by the angular position of the coupling pin supported by the balance plate when the resonator is in or passing through its rest position. In order to stop the mechanical resonator during the braking pulse, the coupling zone of the mechanical resonator with the escapement (-θ ZI ~θ ZI) is therefore declared a "forbidden zone" (it is seen that during the transient phase, braking is possible in this forbidden zone, but the resonator is prevented from stopping in this forbidden zone). In order to maintain the correct operation of the escapement and in particular to guarantee the unlocking phase, within the usable implementation range of the resonator, the safety angle θ Sec is the bond angle θ ZI It should be noted that the safety angle θ may need to be greater than θ for each mechanical movement associated with the correction device according to the first embodiment. Sec It will be possible to determine the value for the bond angle θ ZI may vary depending on the mechanical movement, especially between 22° and 28°.

[0058] The condition of not blocking the resonator in the angular safety zone during the delay correction period is important, since during this delay correction period the passing time must continue to be counted via the escapement (i.e. the timing of the operation of the drive mechanism of the hour indicator). Therefore, in a very advantageous way, the aforementioned frequency F SUP , and the duration of the periodic braking pulses is selected so that, during the aforementioned synchronization phase of the correction period within the first lag correction mode, each of the periodic braking pulses occurs outside the coupling zone of the oscillating mechanical resonator with the escapement, preferably outside the safety zone defined for the mechanical movement, which is achieved by the aforementioned frequency F within the first advance correction mode. SUP , and also applies when selecting the duration of the periodic braking pulses.

[0059] To orient those skilled in the art in the selection of the correction frequency and the corresponding damping frequency, a mathematical model has been created based on the equations of motion of a mechanical oscillator. In order to determine the maximum positive and negative corrections, the resonator is assumed to be in synchronous and stable phase. Furthermore, a simplification is introduced regarding the sustaining force applied to the resonator by the energy source via the escapement and assumed to be of the type cos(ωt). This simplification is based on the assumption that all of the energy supplied to the resonator is within the forbidden zone θ defined above.ZI It should be noted that this is practical because it reduces the maximum value compared to the actual case that occurs in Cor =N·F Bra The safety angle θ in 1 / 2 half cycle corresponds to the number N selected by / 2. Sec The time it takes for the resonator to reach Sec The damping frequency F Bra By defining , the braking pulses are assumed to be very small in duration and therefore separated.

[0060] To determine the maximum correction, and therefore the minimum or maximum duration, depending on whether the time error to be corrected is negative (lag) or positive (lead), the braking pulse provides a time t=0, during which the oscillator is rotated at a safety angle θ Sec Furthermore, in the stable synchronization phase, the resonator is stopped at a safety angle (-1 N )·θ Sec At this point, the subsequent braking pulses must be stopped as soon as possible or as late as possible.

[0061] In such a case, the equation of motion is given by:

[0062]

number

[0063] where τ = Q·T0 / π, T0 is the free vibration period (assumed to be equal to T0c = 1 / F0c in the calculations), and θ0 is the amplitude of the free vibration.

[0064] Therefore, it can be seen that the quality factor Q of the mechanical resonator is included in the equation of motion.

[0065] Correction frequency FS greater than setpoint frequency F0c Cor To obtain T Sec must occur half a period after the resonator has passed its neutral / rest position. Thus, for a given N, we have: θ(T Sec )=-1 N θ Sec where:

[0066]

number

[0067] is.

[0068] Maximum braking frequency is FSB max (N)=1 / T Sec , and the maximum correction frequency is FSC max (N)=N·FSB max / 2.

[0069] A correction frequency FI that is less than the setpoint frequency F0c Cor To obtain T Sec must occur in the half period before the resonator passes its neutral / rest position. Thus, for a given N, we have: θ(T Sec )=-1 N θ Sec where:

[0070]

number

[0071] is.

[0072] The minimum braking frequency is FIB min (N)=1 / T Sec , and the minimum correction frequency is FIC min =N·FIB min / 2.

[0073] 7A and 7B show the RS max (N=1)=FSC max (N=1) / F0c, and RS max (N=2)=FSC max The curves of (N=2) / F0c are shown as a function of the amplitude θ0 of the free vibration of the mechanical resonator for various quality factors Q of this mechanical resonator. The smaller the quality factor, the higher the ratio RS max It can be seen that (N) is large.

[0074] Figure 8 shows the results for the case where the quality factor Q = 100, the free amplitude θ = 300°, and the safety angle θ Sec For a resonator with a lag correction frequency of 0.5°, the values ​​"1" and RS are used in the larger range of correction frequencies for the setpoint frequency F0c and various corresponding values ​​of N that can be considered within the range of the first delay correction mode. max (N) and the ratio RS = FS Cor / F0c is indicated.

[0075] Figure 9 shows the results for the case where the quality factor Q is 100, the free amplitude θ is 300°, and the safety angle θ is Sec = 25°, for a setpoint frequency F0c and various corresponding values ​​of N that can be considered within the range of the first lead correction mode, the smaller range of correction frequencies is max The ratio RI=FI between (N) and the value "1" Cor / F0c indicates.

[0076] As mentioned above, the ranges given in Figures 8 and 9 are the result of a simplified theoretical model. It can be seen that the maximum correction frequency, and the corresponding minimum correction frequency, depend on several parameters. These figures provide a good indication of reality for mechanical movements with reasonably standard characteristics. However, for each given mechanical movement, limit values ​​must be defined if one wishes to approach them in order to achieve a large correction in a relatively short correction period.

[0077] After having described in detail the configuration of the electronic control unit of a first embodiment of a timepiece according to the invention and the operation of the correction device for correcting the delay in the time displayed by the timepiece, the configuration of the electronic control unit according to this first embodiment for correcting the advance of the displayed time according to the second advance correction mode will now be described.

[0078] To enable the implementation of a second lead correction mode, the timepiece comprises a device for blocking the mechanical resonator. Generally, within the scope of the second lead correction mode, the electronic control unit is then configured to be able to supply a control signal to the blocking device when the external correction signal received by the receiving unit corresponds to an indicated time lead to be corrected, the control signal activating said blocking device so as to block the oscillations of the mechanical resonator during a correction period, the correction period being determined by the lead to be corrected, in order to stop the operation of said drive mechanism during said correction period.

[0079] In the first embodiment described with reference to Figures 1-2, the timer 2 comprises a braking device 22, in particular a blocking device formed by a piezoelectric actuator 22A, which is also used to implement the first delay correction mode. Ext corresponds to an advance in the displayed time that should be corrected, logic circuitry 60 of electronic control unit 28A (FIG. 2) sends a control signal S A This timer 70 therefore provides the correction period PA via the "OR" gate 66 or other switch. Cor signal S for activating the braking device 22 over C2 The duration of the signal is the corresponding lead T Err Therefore, the periodic start signal S C2 is the control signal S Cmd The start signal S C2 is applied for a relatively long time, i.e., substantially the entire correction period PA Cor =T ErrIt can be seen that the braking device 22 controls the braking device 22 in the blocking mode of the mechanical resonator during the correction period. For this purpose, the voltage supplied by the power supply circuit 26 between the two electrodes of the piezoelectric strip 24 can therefore be different from the voltage provided to generate the periodic braking pulses to correct the delay. This voltage is selected so that the braking force applied to the mechanical resonator is able to stop the mechanical resonator, preferably very rapidly, and subsequently block it until the correction period has ended.

[0080] In an alternative embodiment, the voltage applied to the piezoelectric strip 24 is variable during the correction period. For example, a higher voltage can be provided at the beginning of the correction period, selected to rapidly stall the resonator, particularly during the half-period of oscillation of this resonator at which the correction period begins, and subsequently the voltage can be reduced to a lower value, but sufficient to keep the resonator stalled. Advantageously, the voltage is adjusted so that the resulting damping force is within the forbidden angular zone (-θ) mentioned above. ZI ~θ ZI ) is selected so that it is not possible to stop the mechanical resonator in the angular stop position. For this purpose, the braking torque is selected so that it is strong enough to stop the resonator and to shut it off at any angular stop position, but is weak enough to prevent this braking torque from stopping the resonator in the forbidden angular zone. Preferably, the resonator is selected so that it is strong enough to stop the resonator in the above-mentioned angular safety zone (-θ Sec ~θ Sec ) is prevented from stopping. The above condition is important when the resonator is not self-starting. In general, it is sufficient that the resonator can be reliably restarted at the end of the correction period.

[0081] According to one particular alternative embodiment that ensures that the resonator is stopped rapidly outside the aforementioned angular safety zone, a preliminary phase is provided that occurs before the correction period in which the resonator is shut off (i.e., where the resonator remains stopped after being stopped rapidly at the beginning of the correction period). During the preliminary phase, the first delayed correction mode available in the first embodiment is used. It is clear that in the synchronization phase of the first correction mode described hereinabove, the passage of the furthest angular position occurs between each braking pulse. Thus, the braking pulses are synchronized with the passage of the mechanical resonator through one of its two extreme angular positions, each of these passages defining the beginning of a half-cycle. This can be exploited by activating the frequency generator 62 during the preliminary phase, which, despite having a relatively short duration, ensures that the resonator is kept at the frequency FS Cor It is intended that this is sufficient to establish a synchronization phase that is synchronized with the preparatory phase. The preparatory phase ends, for example, during the final braking pulse, followed immediately by a correction period during which the braking device is activated in cut-off mode. It is therefore seen that the resonator is cut off outside the angular safety zone. The braking torque for the preparatory phase may be different from that used to correct the delay as described above.

[0082] Since the behavior of the frequency at the beginning of a series of periodic braking pulses during the transient phase can vary, it is almost impossible to determine the error caused by the preliminary phase. However, it is possible to estimate the maximum error. For example, the frequency F SUP = 1.05·F0c (30 seconds correction in 10 minutes) and the duration of the preliminary phase is 10 seconds (the selected duration is greater than the duration of the possible transient phase), the maximum error can be estimated to be equal to 0.5 seconds (half a second). For a mechanical movement, such an error is not negligible, but this error is relatively small since conventional mechanical movements generally have a daily rate of 0 and a range of 5 to 10 seconds.

[0083] Referring to FIG. 10, a second embodiment of a timepiece according to the invention will be described, which differs from the first embodiment in the configuration of the shutoff device, thereby advantageously enabling the implementation of a second mode for correcting advances in the hour indicator associated with the timepiece's mechanical movement. This mechanical movement 92 includes a conventional escapement 94 formed by a pallet wheel 95 and a pallet lever 96 that can oscillate between two pegs 95. The pallet lever includes a fork 97 between horns, which are typically inserted every half cycle, and a pin 98, which also forms the escapement, and is supported by a plate 100 that is integral with or formed integrally with a staff 102 (i.e., the staff is machined to have a longitudinal profile that defines the plate) of a balance 104 (partially shown) of the mechanical resonator. The plate 100 is circular and is centered on the central axis of the staff 102, which defines the axis of rotation of the balance 104.

[0084] The timepiece comprises a shutoff device 106, separate from the braking device 22A (FIG. 1) used to correct the loss. This shutoff device is therefore dedicated to implementing the second lead correction mode. The shutoff device is formed by an electromechanical actuator, in particular a piezoelectric actuator of the same type as that described with reference to FIG. 1. According to the alternative embodiment shown, the actuator comprises a flexible piezoelectric strip 24A, two electrodes of which are supplied with a voltage by a power supply circuit 26A. At its free end, the strip 24A has a protrusion 107 forming a stud, which is located on the plate 100 side. The strip extends a short distance from the circular circumference of the plate in a direction parallel to the tangent to this circumference. The plate has a through-hole 108 radially opening from its periphery, the contour of which in the general plane of the plate is provided so that the stud 107 can be received therein when it is positioned angularly facing this cavity and when the piezoelectric actuator 106 is activated. According to the alternative embodiment shown, the cavity 108 is diametrically opposite the pin 98, and the stud is angularly located at the zero position of the pin (i.e., the angular position of the pin when the resonator is at rest or passes through its neutral position). This zero angular position of the pin typically defines the zero angular position of the balance 104, and therefore of the mechanical resonator, in a fixed angular coordinate system relative to the mechanical movement 92 and centered about the axis of rotation of the balance.

[0085] In an equivalent alternative embodiment, the cavity can be configured at another angle to the pin, for example 90°, and the actuator 106 is therefore positioned on the periphery of the plate so that the stud 107 is diametrically opposite the cavity when the resonator is at rest. Therefore, when the piezoelectric actuator is activated, regardless of the half-period and angular position, the stud will enter the cavity when the resonator is at an angular position that is substantially equal to 180° in absolute value (this is strictly the case when the balance is in phase, i.e., when the pin is aligned with the respective centers of rotation of the balance and of the pallet lever when the resonator is at rest). The value of 180° is clearly outside the safety zone (larger than the safety angle defined above), and it is usually smaller than the range of amplitudes of the mechanical resonator, which corresponds to its usable operating range.

[0086] Furthermore, according to an advantageous alternative embodiment shown in FIG. 10 , the sidewalls of cavity 108 are parallel to a radius passing through the center of the cavity and to the balance's axis of rotation. In an equivalent alternative embodiment, these sidewalls are radial. Similarly, stud 107 has two sidewalls that are perpendicular to the main plane of the plate, and the sidewalls are parallel to a radius passing through the center of the balance and to the balance's axis of rotation, or, in an equivalent alternative embodiment, are substantially radial to the axis of rotation. Thanks to this configuration, when stud 107 is inserted into cavity 108, so that the cavity serves as a housing for the stud, the stud blocks the rotation of plate 100, and thus balance 104, with a substantially tangential force, the direction of which is substantially parallel to the overall longitudinal direction of piezoelectric strip 24A. When the actuator 106 is activated, the end of the strip carrying the stud 107 undergoes a substantially radial displacement relative to the axis of rotation of the balance, and the stud can therefore either apply an essentially radial force to the circular outer surface of the plate 100 or at least partially enter the cavity 108, as a function of the angular position of the balance. The actuator need only be configured so that, when this actuator is activated, the stud can undergo a displacement sufficient to be inserted into the cavity when the cavity is placed in an angular position that substantially corresponds to the angular position of the stud (in an angular coordinate system fixed relative to the stud).

[0087] If the cavity does not face the stud when the proximal surface of the stud reaches the circular circumference of the plate, a relatively small frictional force can be applied when the stud comes into contact with the circular outer surface of the plate at the beginning of the correction period, i.e., after activation of the actuator. This can ensure that the amplitude of the resonator does not decrease significantly during the initial damping caused by the stud exerting a radial force against this circular outer surface. Furthermore, if the stud is inserted into the cavity while the cavity is positioned facing the stud, the radial force applied to the plate by the piezoelectric strip can be very small or even zero. Therefore, the electrical energy required to shut off the resonator during the correction period can be relatively small, much smaller than in the first embodiment.

[0088] When the correction device of the timepiece receives an external correction signal corresponding to the correction of the advance detected in the time indicator, its control logic circuit outputs a control signal S for a period substantially equal to the time error to be corrected, similar to that described above within the scope of the first embodiment. C2 to the braking device, thereby activating the isolating device 106, similar to the operating method of the first embodiment. Thanks to the configuration of the cavity in the circular plate centered on the rotation axis of the resonator and the actuator with a corresponding portion, but preferably narrower than the cavity, configured in the alternative embodiments described herein to undergo a substantially radial movement between a non-interacting position corresponding to a state where it is not supplied by the actuator and a position where it interacts with the balance of the resonator, corresponding to a state where it is supplied by the actuator, the initiation of activation of the isolating device 106 can occur at any time, regardless of the angular position of the resonator and regardless of the direction of the oscillatory motion (and therefore independent of the current half-period of the two half-periods that make up each oscillation period). This is very advantageous.

[0089] Finally, with regard to the second embodiment, the electromechanical actuator may be of a different type from that shown in FIG. 10 . For example, in an alternative embodiment, the actuator may comprise a ferromagnetic or magnetized core that can be displaced under the effect of a magnetic field generated by a coil. In particular, this core is collinear with the coil and comprises at least an end that emerges from the coil when the actuator is activated, forming a finger configured to be inserted into a cavity in the plate, the finger having a distal end in the form of a stud 107. In a preferred alternative embodiment, the actuator is a bistable actuator. The actuator's supply is advantageously maintained during activation, moving it from a non-interacting position to an interacting position until the stud is at least partially inside the cavity 108. Such an alternative embodiment is of particular interest because the actuator must not exert any blocking force by applying radial pressure to the balance element of the resonator in the two stable positions of the actuator, corresponding to the non-interacting and interacting positions provided, respectively. In this preferred alternative embodiment, the power consumption can be very low, regardless of the duration of the correction period, which is a great advantage.

[0090] With reference to Fig. 11, a third embodiment of a timepiece according to the invention will be described, which differs from the first embodiment essentially by the configuration of the cut-off device, which advantageously makes it possible to implement a second mode for correcting a lead in a time indicator associated with the mechanical movement of the timepiece. References already made with reference to Figs. 1 and 2 will not be described again in detail here. As with the second embodiment, a timepiece 112 according to the third embodiment comprises a cut-off device 114 that is separate from the braking device 22B used to correct a lead. The braking device 22B is similar to the braking device 22A described above and operates in the same way, i.e., the braking device 22B is adapted to implement the first lead correction mode, as described in detail above. This braking device 22B comprises a power supply 26B, which is partly shared with the power supply of the cut-off device 114 and which is supplied with a control signal SC1 In this case, the timer comprises a piezoelectric strip 24B in a bracket shape provided to make it easier to arrange, as a possible alternative here, the piezoelectric strips 24B and 25 forming the disconnecting device on the same surface of the support of the shared power supply 26B. However, other alternative embodiments may provide a braking device identical to that shown in FIG. 1, in particular in which the power supply circuit is completely separate from the power supply circuit of the disconnecting device.

[0091] The isolating device 114 is noteworthy for at least two reasons. First, it acts on a conventional mechanical resonator 14 without any modifications, and in particular without any specific machining, unlike the second embodiment. Furthermore, the isolating device is a bistable element, i.e., it has two stable positions, which in this case are the lever 115. The isolating device is configured so that the first of the two stable positions of the lever corresponds to a position in which it does not interact with the balance 16, while the second of these two stable positions corresponds to a position in which it locks the resonator via a radial force exerted on the outer edge 20 of the balance by the strip 116 forming the lever 115. The strip 116 pivots about an axis formed by the mechanical movement 4A (in another alternative embodiment, the lever is configured on a support whose pivot axis is separate from the mechanical movement and belongs to the compensation module). In the alternative embodiment, this axis is formed by a fixed peg around which the annular end of the strip 116 is attached. The strip may be rigid or semi-rigid, with slight flexibility being advantageous.

[0092] The strip 116 is associated with a particular magnetic system that results in the bistable nature of the lever 115 and therefore of the shutoff device 114. The magnetic system comprises a first magnet 118 supported by the strip and therefore fixed to it so as to rotate therewith, a second magnet 119 arranged fixedly inside or relative to the mechanical movement, and a small ferromagnetic plate 120 arranged between the first and second magnets at a fixed short distance from or against the second magnet 119 (for example, the small plate is bonded to this magnet so that only an adhesive layer separates the magnet from the small plate).

[0093] First magnet 118 and second magnet 119 have opposite magnetic polarities, and their respective magnetic axes are substantially aligned. Therefore, without the small ferromagnetic plate, these two magnets would always repel each other, and in the absence of forces external to the magnetic system, the lever would remain in or always return to a position where the strip abuts against peg 124, restricting its rotation. However, thanks to the configuration of the small ferromagnetic plate, the magnetic force between the two magnets is reversed. More specifically, when moving magnet 118 moves closer to the small ferromagnetic plate from its remote position (as shown in FIG. 11 ), the repulsive force decreases as the moving magnet moves closer to the small ferromagnetic plate, then cancels out and finally reverses. Therefore, when moving magnet 118 is positioned very close to or facing small ferromagnetic plate 120, the moving magnet is subjected to a magnetic attractive force. This surprising physical phenomenon is detailed in Swiss Patent Application Publication No. 711889, which further includes several applications in horology.

[0094] The lever 114 is configured to assume two stable positions in the absence of forces external to the blocking device's magnetic system. The first stable position is a non-interacting position, in which the strip 116 abuts against the peg 124, thereby exposing the moving magnet 118 to a magnetic repulsion force that maintains the lever against the peg. The second stable position is an interacting position, in which the strip 116 abuts against the outer edge 20 of the balance 16, thereby exposing the moving magnet 118 to a magnetic repulsion force that maintains the lever against the outer edge. The small ferromagnetic plate 120 is configured so that when the lever is in its second stable position, the strip exerts a radial force that shuts off the balance 16, and thus the resonator 14. In order for the strip to exert a shutoff force against the outer surface of the outer edge 20, the surface of the small plate 120 facing the moving magnet 118 must be slightly retracted relative to the proximal surface of the moving magnet when the strip 116 contacts the outer edge. If the strip is semi-rigid and therefore has a certain flexibility, the moving magnet can eventually abut against the proximal surface of the small ferromagnetic plate, but in this case the strip is in a bent state.

[0095] The disconnecting device comprises a device for actuating the bistable lever 115 in order to displace this lever in both directions between its two stable positions. This actuating device 126 is controlled by the logic circuit of the electronic control unit via its power supply circuit, which in turn outputs a control signal S C2 It is noteworthy in this embodiment that the interrupting force exerted by the interrupting device does not come from the power supply to the interrupting device, but from the magnetic system forming the interrupting device. Thus, for the second advance correction mode, the interrupting device only requires power at the beginning and end of the interrupting period while switching the bistable lever between its two stable states.

[0096] For illustrative purposes only, the actuation device 126 is formed by a piezoelectric device including a piezoelectric strip 25, which can bend in both directions from its rest position (unactivated position) between two electrodes having positive and negative electrical polarities by applying a voltage supplied by a power supply circuit 26B. The lever 115 includes a fork 122 defining a cavity, within which the free end of the piezoelectric strip 25 is housed. The width of the cavity is preferably greater than the free end of the strip 25, and the strip is configured to abut a first sidewall of the cavity when the bistable lever is in a first stable position and abut a second sidewall of the cavity when the bistable lever is in a second stable position. By adjusting the width of the cavity, the piezoelectric strip 25 can be made substantially straight, i.e., not bent, in either of the two stable positions of the lever. However, taking into account the path followed by the ends of the piezoelectric strip, it may be advantageous to allow them to remain slightly bent in the absence of voltage applied by the power supply, as shown.

[0097] In one advantageous alternative embodiment, the actuation device of the lever is formed by an electromagnet-coil system, in which a magnet is in particular fastened to the lever and a coil is fastened to the lever support substantially aligned with the magnet. Depending on the polarity of the voltage applied to the coil, the lever is subjected to a magnetic attractive or repulsive force, making it possible to easily pass the lever in both directions from one to the other of two stable positions.

[0098] In another alternative embodiment, which produces the same physical phenomenon and therefore the required effect, a small ferromagnetic plate 120 is configured rigidly connected to the moving magnet 118. Finally, another alternative embodiment provides a combination of the second and third embodiments. For this purpose, the strip of the lever is provided with a stud protruding towards the outer edge 20 in the area where contact is made with this edge, the outer edge having a cavity along its generally circular circumference. Those skilled in the art will know how to configure the blocking device so that its first stable position is a non-interacting position and its second stable position is an interacting position, with the stud at least partially inserted into the cavity and initially exerting dynamic dry friction generally against the outer surface of the outer edge when the lever is actuated by the actuation device, and moving from its first stable position to its second stable position at the beginning of the lead correction period when the cavity is facing the stud during the oscillation of the balance, before penetrating the cavity.

[0099] A fourth embodiment of the timepiece is described below with reference to Figures 1 and 12. This fourth embodiment is a preferred embodiment that differs from the first embodiment substantially as a result of its advance correction mode, as well as some extensions and alternatives to some units of the correction device 132.

[0100] Firstly, the receiver unit 30B of the correction device is a BLE (Bluetooth Low Energy) unit. Secondly, the power supply 130 of the correction device is more advanced than the alternative shown in the first embodiment (Fig. 2). The energy harvester is a solar cell 54A, specifically located on the dial or on the bezel holding the glass protecting the dial. This dial as a whole forms part of the time display. Furthermore, a photodiode 136 is provided, which receives an external correction signal S provided by an external electronic device. Extreceive a light signal for activating the correction device (in other words, starting the method for correcting the displayed time implemented inside the correction device 132), provided by an external electronic device, in particular the mobile phone 40, so as to start / initiate in the timer a cycle of correcting the displayed time based on the received light signal;

[0101] The power supply 130 comprises a circuit 134 for managing the power supply to the correction device 132. This circuit is able to receive various information from the electrical accumulator 56 and is configured to generate a wake-up signal S when the photodiode 136 receives a particular light signal from the mobile phone 40. W-UP The photodiode 136 receives a signal from the photodiode 136. Various measures known to those skilled in the art can be taken to prevent the photodiode from transmitting unwanted wake-up signals to the correction device. In particular, a specific narrow frequency band can be selected. Furthermore, the light signal can be coded, in particular by modulating the light intensity, so that the photodiode 136 or the management circuit 134 can determine whether the logic code corresponding to this modulation actually relates to the intended wake-up signal. Once the management circuit 134 receives a valid wake-up signal, it detects the available energy level in the accumulator 56. As in the first embodiment, if the energy level is insufficient to complete the correction method, the management circuit can react in various ways. In particular, the management circuit can wake up the BLE unit and send a message via the BLE unit to the mobile phone, which then informs the user via an electronic display. In this case, the management circuit can either remain in standby mode to receive electrical energy via a solar cell or other energy harvesting, which is also provided, or start the correction cycle as soon as possible, knowing that there is a risk that the cycle will not be completed accurately due to insufficient available energy.

[0102] If the available energy level is sufficient for a correction cycle, the management circuit 134, in a first alternative embodiment, first applies an external correction signal S Ext The BLE unit typically has the resources to verify that an external signal received at the correct frequency is in a standard format, but it may be necessary to activate control logic 60A to analyze the signal received by the BLE unit to determine whether it is received at the correct frequency and has the correct format. In this case, the analysis is performed by generating a digital correction signal S Cor The digital correction signal S Cor indicates, if necessary, that the received signal is not proper or incomplete. Thus, in a second alternative embodiment, the managing circuit directly wakes up the BLE unit and the control logic, but preferably not other elements of the correction device. If the correction signal is not received or is not received correctly, the managing circuit 134, in an alternative embodiment, notifies the mobile phone (directly or via the control logic 60A) of this (and therefore the control logic 60A must be woken up to be notified) and can wait for a new external correction signal within a further period of time or return to a "standby" mode pending a new wake-up signal. In another alternative embodiment in which the timer comprises electronic or electromechanical means for providing a signal visible to the user, the managing circuit 134 may use this means to notify the user that the correction cannot be performed because the managing circuit 134 has not received or is not receiving correctly the external correction signal.

[0103] In the first alternative embodiment described above, the BLE unit receives an external correction signal S Ext If the digital signal S is received at the correct frequency and in the correct format, the BLE unit activates at least one control logic circuit 60A and provides a digital correction signal to the control logic circuit 60A for analysis and continuation of the correction cycle. Cor The expected time information, especially the time error T Err, and the mathematical symbol "+ / -" indicating whether a delay or advance should be corrected (this last information is binary, so a single bit can be provided for this purpose), the management circuit 134 activates the power supply circuit 26C of the entire correction device and the braking device.

[0104] The fourth embodiment is characterized by an implementation of a first lag correction mode similar to the first embodiment, and by an implementation of a first lead correction mode, as described above but not implemented in the first embodiment, such that any correction provided herein is performed by a series of periodic braking pulses during the correction period. One main alternative embodiment provides all of the braking pulses having the same duration Tp. Thus, only one timer 64 is needed to determine the duration of the braking pulses, which in the alternative embodiment shown in FIG. 12 is configured within the power supply circuit 26C. This timer sends an activation / activation signal S to a switch 138 placed between a voltage source 140 and the braking member 24C acting on the balance. Act The braking member 24C is similar to the piezoelectric strip of other embodiments shown for example for the first embodiment (FIG. 1). Thus, the switch 138 controls the supply of power to the actuator forming the braking device. The timer 64 receives a first control signal S1 from the switching device 66A. Cmd and the switching device is controlled by logic circuit 60A, so that the first control signal is at three different frequencies F SUP , F INF , and F0c, respectively. FS , S FI , and S F0c The periodic digital signal is selectively formed by one of the periodic digital signals T, which periodically resets the timer to a selected frequency, which in response causes the switch 138 to momentarily conduct, thereby generating a series of periodic braking pulses at the selected frequency, thereby periodically activating the actuator for a duration Tp.

[0105] If the digital correction signal indicates that the time error corresponds to a delay to be corrected, or if the control logic circuit itself has determined such a time error to be corrected based on information contained in the external correction signal, then the logic circuit 60A will adjust the selected frequency F SUP As a function of the corresponding correction period PR Cor or the frequency F during the current correction cycle SUP To accomplish this, the logic circuit uses the formula given above for this calculation. Cor The frequency F SUP To apply a series of braking pulses at , the logic circuit uses the frequency generator 62 described above to generate a periodic digital signal S via a switch 66A controlled for this purpose by the control logic circuit. FS frequency F SUP This is provided to timer 64.

[0106] If the digital correction signal indicates that the time error corresponds to an advance that should be corrected, or if the control logic circuit itself has determined such a time error to be corrected based on information contained in the external correction signal, then the logic circuit 60A will adjust the selected frequency F INF As a function of the corresponding correction period PA Cor or during the current correction cycle, at the frequency F defined above. INF To accomplish this, the logic circuit uses the formula given above for this calculation. Cor The frequency F INF To apply a series of braking pulses at , the logic circuit uses frequency generator 142 to generate a periodic digital signal S via switch 66A, which is controlled for this purpose by the control logic circuit. FI frequency F INF This is provided to timer 64.

[0107] Generally, to enable implementation of the first lead correction mode, the electronic control unit 28B controls the frequency generator to generate a frequency F when the external correction signal received by the receiver unit corresponds to the indicated time lead to be corrected. INF providing a control signal derived from the periodic digital signal provided at to the damping device during the correction period to activate the damping device and cause the damping device to apply a series of periodic damping pulses to the mechanical resonator at a frequency F INF The frequency F INF A series of periodic braking pulses at can bring about a synchronization phase during the correction period, and the vibration of the mechanical resonator is synchronized with a correction frequency FI that is smaller than the setpoint frequency F0c provided to the mechanical resonator. Cor This frequency F INF is provided, and the braking device is configured such that the (duration of) the correction period, and therefore the number of periodic braking pulses in said series of periodic braking pulses, is determined by the lead to be corrected.

[0108] The correction device of the fourth embodiment includes an enhancement, particularly for corrections at frequencies relatively far from the setpoint frequency, that increases the accuracy of the correction performed and allows for the application of a relatively large braking torque without the risk of permanently stopping the mechanical resonator by stopping the mechanical resonator within the angular coupling zone of the resonator with the escapement, or generally within the aforementioned angular safety zone, during a braking pulse at the beginning of the correction period. According to this enhancement, the timepiece comprises a device for determining the passage of the oscillating mechanical resonator through at least one specific position, which determines the specific position of the mechanical resonator and allows the electronic control unit to determine the specific moment when the oscillating mechanical resonator is at said specific position and thus the phase of the resonator. Furthermore, the electronic control unit is configured to initiate a first activation of the braking device as a function of said specific moment, which occurs at the start of the correction period and generates a first interaction between this braking device and the mechanical resonator.

[0109] According to an advantageous alternative embodiment of the enhancement described above, and with reference to FIG. 12, the correction device further comprises a frequency generator 144, which generates a periodic digital signal S F0c at a setpoint frequency F0c provided for the resonator. F0c , is configured to provide a control signal derived from the brake device to activate the brake device during a preliminary period immediately preceding the correction period, causing the brake device to generate a preliminary series of periodic brake pulses that can be applied to the mechanical resonator at the setpoint frequency F0c. To this end, the control logic circuit 60A controls the generator 144 to provide a control signal S PP During the preliminary series of periodic braking pulses, the duration of the periodic braking pulses Tp and the braking force applied to the oscillating resonator are such that the coupling zone of this oscillating resonator and its associated escapement is (θ ZI and θ ZI and ), or preferably within a predetermined safety zone (θ Sec and θ Sec and ) are provided so that none of these braking pulses can stop the vibrating resonator (these zones are described above).

[0110] Furthermore, the duration of the periodic braking pulses and the braking force applied to the vibrating resonator during the preliminary series of periodic braking pulses are provided to generate a preliminary synchronization phase, at least at the end of the preliminary period, in which the vibration of the mechanical resonator is synchronized (on average) to the setpoint frequency F0c. In the alternative embodiment shown, the voltage source 140 is variable and controlled by a logic circuit 60A, which applies a control signal S2 to the voltage source. Cmd The voltage level applied to the braking member 24C can be varied to provide a differential voltage, thereby varying the braking force. Thus, a weaker braking force can be applied during the preliminary period than that applied during the subsequent correction period. The braking force can also be varied during the preliminary period and / or the correction period.

[0111] The correction period intended to correct an advance or a delay immediately follows the preliminary period. More specifically, at the beginning of the period for correcting the displayed time, the frequency F INF or F SUP The initiation of the first braking pulse in the preliminary period occurs after a time interval determined relative to the start of the last braking pulse of the preliminary period so that this first braking pulse occurs outside the predetermined safety zone covering the aforementioned coupling zone. This condition is easily satisfied because the resonator is in the synchronization phase at least at the end of the preliminary period, which means that the resonator stops during the last braking pulse of this preliminary period. Therefore, a reversal of the direction of rotation occurs during the aforementioned last braking pulse, and as a result, the start of a new half-period of the resonator's oscillation occurs during this last braking pulse. The correction device can therefore know the oscillation phase with an accuracy of Tp / 2 (e.g., an accuracy of 3 ms). As a result, the electronic control unit can be configured so that, after a determined time interval has elapsed since the aforementioned last braking pulse and it is certain that the first braking pulse is outside the predetermined safety zone, the control logic circuit can determine the initial moment for initiating the first braking pulse that satisfies the aforementioned condition by activating the frequency generator 62 or 142 according to the necessary correction.

[0112] Moreover, the moment said braking pulse is initiated and during this first pulse, and subsequently during the subsequent periodic braking pulses during the correction period, the braking force applied to the vibrating resonator is at a correction frequency FI Cor or FS Cor The synchronization phase in preferably begins as soon as the first braking pulse is applied, or as soon as the second braking pulse is applied if the first braking pulse is intended to reduce the amplitude of the oscillations without trying to stop the resonator, so that this synchronization phase is provided to last for the entire duration of the correction period. In a particular alternative embodiment, the first braking pulse of the correction period is adjusted to the frequency F according to the required correction after the moment when the last braking pulse of the preliminary period occurs.SUP or F INF In another particular alternative embodiment, the aforementioned time interval occurs after a time interval corresponding to the reciprocal of the correction frequency FS Cor or FI Cor or the reciprocal of twice this frequency FS Cor or FI Cor . The enhancements mentioned above are noteworthy in that they use available resources to determine the oscillation phase of the resonator, specifically the damping device provided to perform the necessary corrections. No specific sensor is required to determine this phase. Moreover, the standby period (typically up to T0c / 4) does not introduce any significant time drift. Although the generators of the various frequencies are shown separately in Figure 12, it is understood that a single programmable frequency generating device could be used.

[0113] A second embodiment of an assembly 150 according to the present invention will now be described with reference to Figures 13 to 15. The assembly 150 comprises a timepiece 154 according to the fifth embodiment and an external device 152 according to the second embodiment of the assembly according to the present invention. The timepiece is a wristwatch (hereinafter referred to as a watch), and the external device forms a housing with a recess for receiving the watch in a given position. The housing 152 comprises a photographic device 156, which is arranged in the lid of the housing so as to capture an image of the entire display of the timepiece when the lid is closed with the timepiece 154 correctly placed in the recess.

[0114] The housing 152 contains various electronic circuits and units. a photographic device comprising a photographic sensor formed by an array of photodetectors; an image processing algorithm configured to determine the position of at least one determined hand of the indicator of the timepiece in an image captured by the photographic device (it should be noted that this algorithm may be processed in an external server in communication with the housing); - A time base that can provide accurate actual time, an algorithm for calculating a time error between first time data and second time data, the first time data being shown by a display at a given time instant substantially supplied at said given time instant by a time base and detected by an external device via a photographic sensor and an image processing algorithm, and the second time data corresponding to the first time data; a transmitter for transmitting an external correction signal containing information related to said time error; and the transmitter is formed by a BLE unit in the alternative embodiment shown.

[0115] The housing 152 further comprises an electronic display 153, a central control unit enabling the accurate actual time to be received periodically or on demand, and a communication unit (RF unit) capable of receiving the accurate actual time via an antenna provided for this purpose (radio synchronization), or a WIFI unit for receiving the accurate actual time via the Internet, or a GPS unit. The housing also comprises a power source which can be powered or recharged via a USB-type plug or other plug. Finally, the housing comprises a wireless magnetic induction charging unit, in particular for the watch 154 equipped with the fitness module. This wireless charging unit is preferably arranged in a support which is inserted into a recess in the housing so as to be close to and below the watch when it is placed in the housing, in particular to be able to charge the watch's battery 56A.

[0116] The watch 154 comprises various electronic circuits and elements. What has already been mentioned above will not be explained again in detail here. The watch comprises a BLE unit 30B for receiving various signals, including in particular signals for correcting the time displayed by the watch, and a braking device 22C. The watch receives a wake-up signal S from an electronic control unit, which will be described below. ActThe components of the braking device 22C receiving the signal have already been described above. In this case, the watch 154 preferably comprises a rechargeable battery 56A that is recharged by magnetic induction (by contactless means) and a power management circuit 134A similar to that described above with reference to the watch of Fig. 12. Optionally, the watch further comprises a fitness module 156 and, in particular, an electronic display 158 associated with the fitness module, which may use a BLE unit to communicate with electronic devices external to the watch, in particular the housing 152, a mobile phone, or any other suitable electronic device, for example a computer.

[0117] According to an enhanced alternative embodiment, the electronic control unit 28C of the watch 154 is configured to be able to implement a first delay correction mode and to be able to correct the advance according to the first correction mode or the second correction mode described above. This electronic control unit therefore comprises a control logic circuit 60B, which controls the frequencies F0c, F INF , and F1 SUP and F2 SUP controls the switching device 66B together with the frequency generating device. SUP and F2 SUP is the frequency F defined above SUP This frequency generating device has two different values ​​to be selected for the frequency F0c, the generator 144 at the frequency F0c for implementing the preliminary period already described within the scope of the fourth embodiment of the timepiece of the invention, and the frequency F INF and the respective frequency F1 SUP and F2 SUP Two periodic digital signals S FS1 and S FS2 In other words, the frequency generating device is configured to generate a frequency F1 so as to compensate for the displayed time delay. SUP and F2 SUP The digital signal generator is configured to selectively generate a periodic digital signal at a frequency F1 to control the braking device. SUPand F2 SUP is the correction frequency FS for correcting the delay in the first correction mode. Cor are two frequencies F1 SUP and F2 SUP For two different values ​​of F1 Cor and F2 Cor The correction frequency F2 is provided so that it can be taken Cor is the correction frequency F1 Cor Higher than.

[0118] Frequency F1 SUP is advantageously selected when the delay to be corrected is lower than a given value in absolute value, while frequency F2 SUP is selected if this delay is greater than or equal to this given value. SUP is a function of the value of the delay to be corrected, and has at least two different values ​​F1 SUP and F2 SUP In response to the activation of the generator, the control signal S1 Cmd is a periodic digital signal S F0c , S FI , S FS1 and S FS2 This signal S1 Cmd Itself is the start signal S Act It will be noted that no timer is provided to determine the duration of the braking pulse, since in this alternative embodiment a periodic digital signal S F0c , S FI , S FS1 and S FS2 is intended to define this duration by a duty cycle determined between a logic high ("1") and a logic low ("0"). Thus, for example, the duration of the logic high determines the duration of each braking pulse, and switch 138 is closed (transistor is turned on) on the rising edge of the supplied periodic digital signal and is opened (transistor is turned off) on the falling edge of this periodic digital signal.

[0119] Furthermore, the electronic control unit 28C comprises a timer 70 similar to that described with reference to Figure 2, which allows the implementation of the second correction mode already described in the first embodiment of the timepiece according to the invention. This timer 70 is activated by a control signal S1 Cmd control signal S3 which activates the braking device via an "OR" logic gate 166 which also receives Cmd (It will be appreciated that a switch operated by a logic gate can be incorporated into switch 66B, making the logic gate incorporated in the diagram of FIG. 15 unnecessary to distinguish between the first and second correction modes.) Thus, either the first or second correction mode can be selected to correct the lead.

[0120] If the lead to be corrected is less than a given value, the first correction mode is advantageously selected, while if the lead to be corrected is equal to or greater than this given value, the second correction mode is selected. The selection of the first or second correction mode may also depend on the level of the rechargeable battery 56A, since the first lead correction mode allows a braking device of the electromechanical actuator type (e.g., the piezoelectric actuator 22A in FIG. 1 ) to consume less electrical energy compared to the second correction mode, in which the braking device has a single stable position in the absence of electrical power. Similarly, the selection of the generator 62A or the generator 62B may also depend on the level of the rechargeable battery, since the first lag correction mode a priori requires a stronger braking torque when the ratio between the correction frequency and the setpoint frequency is relatively high.

[0121] A fifth embodiment of the timepiece not only includes means for correcting the displayed time error resulting from the time drift of the vibrating resonator or from an inaccurate manual time setting operation, but also means for enabling the displayed time to be changed at the appropriate moment during seasonal time changes (from standard time to daylight saving time or from daylight saving time to standard time). To this end, the clock 154 includes an internal clock circuit 162 and a programmable counter 160. An application installed on the external device (the housing 152 or the mobile phone 40 in FIG. 1 ) includes a “seasonal time change” function for communicating with the clock and enabling the clock’s correction device to be activated, programming the clock 154 to move forward or backward by one hour (or half an hour, as appropriate) on the night of the scheduled time change. To this end, the external device is configured to transmit a correction signal related to the seasonal time change to the clock via a transmitter provided for communication with the clock. This correction signal includes an indication of the planned time jump and the direction of the jump (+ / - hours), as well as the time remaining until the night and hour when the time change is planned (e.g., a period of 15 days, 8 hours, and 20 minutes). Thus, the external device not only has the resources necessary to know the exact actual time, but also the resources necessary to know the date. Based on the date of the hourly instant when the "seasonal time change" function is activated, the application easily calculates the aforementioned remaining time.

[0122] When clock 154 receives an external correction signal indicating an upcoming time change, control logic circuit 60B programs counter 160 so that, after receiving a reset signal from the logic circuit, counter 160 measures the time remaining until the scheduled time change. Alternatively, the start of time measurement occurs as soon as clock circuit 162 is activated after the counter is programmed. This activation occurs quickly after receiving the external correction signal. To perform a seasonal time change on a scheduled night, clock 154 may take advantage of the fact that it can be recharged by a charging unit within housing 152. More specifically, since the time change is typically scheduled to occur in the evening after midnight, the user can place the clock in the housing on that night and activate a recharge of the clock battery (if this charging is not automatic). This ensures that the clock has enough energy to perform a relatively long correction. For such a correction, the clock will operate for a correction period PA Cor After this, the second advance correction mode is selected by starting the timer 70 or the correction period PR calculated for the delay corresponding to the "one hour" jump. Cor For generator F2 SUP By starting the generator F2 SUP For example, the ratio RS = F2Cor / F0c is provided to be greater than 1.10, preferably greater than 1.15. As indicated above, the first delay correction mode allows, for example, a one-hour correction within a six-hour correction period. Even a one-hour correction within a five-hour period is possible.

[0123] It should be noted that the damping device can be formed by a different type of actuator than that described above, in particular an electromagnetic actuator with a magnet-coil coupling system arranged to directly damp the mechanical resonator, in which at least one magnet is fastened to the balance or to a support of the balance of the resonator and at least one coil is supported by this support or by the balance of the resonator.

[0124] A sixth embodiment of a timepiece according to the invention will now be described with reference to Figures 16 to 18. This sixth embodiment is configured so that it is possible to implement the second lead correction mode described above in the preceding embodiments, in addition to the second lag correction mode which will be described in more detail herein.

[0125] A timepiece 170 according to the sixth embodiment is partially shown in Figure 16, where only the mechanical resonator 14A of the mechanical movement is shown. With the exception of the device for correcting the displayed time, the other elements of the timepiece are similar to those shown in Figure 1. The mechanical resonator comprises a balance 16A associated with a balance spring 15. The balance comprises an outer edge 20A having a protrusion 190 extending radially around its periphery. No other element of the balance extends to the radial position of the end of the protrusion 190.

[0126] The balance includes a mark 191 formed by successive asymmetric bars that have different optical reflectance coefficients or simply different reflectances to light emanating from the optical sensor 192. Specifically, the successive bars are at least two successive black bars of different widths, separated by a white bar, with the width of one of the black bars equal to the sum of the widths of the other black and white bars. The bars are therefore understood to form a kind of code with a transition in the center of the mark 191. Instead of black and white bars, other colors can be used. In alternative embodiments, the black bars correspond to the non-glossy areas of the outer edge, while the white bars correspond to the glossy areas of the outer edge. The black bars could also correspond to notches in the outer edge with inclined surfaces. Therefore, multiple alternative embodiments are possible. While the mark 191 is shown in the description at the top of the outer edge, it should be noted that in the alternative embodiment shown, the mark is located on the outer surface of the outer edge because the optical sensor is configured on the main plane of the balance 16A. In another alternative embodiment, the mark is located on the top or bottom surface of the outer edge as shown, and the sensor is therefore rotated 90° to illuminate this mark.

[0127] The optical sensor 192 is configured to detect the passage of the oscillating resonator through its neutral position (corresponding to angular position "0" for the protrusion 190) and to determine the direction of movement of the balance during each passage through this neutral position. This optical sensor comprises an emitter 193 that emits a light beam towards the outer edge 20A and is configured to illuminate the mark 191 as the resonator passes through its neutral position, and a receiver 194 that is configured to receive at least a portion of the light beam reflected by the outer edge at the mark. The optical sensor thus forms a device for detecting a specific angular position of the balance, enabling the electronic control unit to determine the specific instant at which the oscillating mechanical resonator is at a specific angular position, and also for determining the direction of movement of the balance during the passage of the oscillating resonator through the specific angular position. Other types of detectors for detecting the position and direction of movement of the resonator, in particular capacitive, inductive, or other detectors, may be provided in other alternative embodiments.

[0128] Furthermore, the timepiece 170 comprises a device for damping the resonator, formed by an electromechanical device 174 with a bistable moving abutment. An alternative embodiment is provided by way of non-limiting example in Fig. 16. The electromechanical device 174 comprises an electromechanical motor 176 of the clock stepper motor type, having small dimensions, powered by a power supply circuit 178, which comprises a control circuit, and which receives a control signal S4. CmdThe motor is configured to generate a series of three electrical pulses upon receiving the signal, which are provided to the motor coils, causing the motor rotor 177 to advance one step, or half a rotation, for each electrical pulse. The series of three electrical pulses are provided to rapidly drive the rotor in a continuous or near-continuous manner. The rotor pinion meshes with an intermediate gear 180, which in turn meshes with a gear having a diameter equal to three times the diameter of the rotor pinion and which fixedly holds a first bipolar permanent magnet 182. Given the diameter ratio between the pinion and the gear holding the magnet 182, the gear rotates half a rotation during each series of three electrical pulses. Thus, the first magnet has a first rest position and a second rest position, the first magnet having a magnetic polarity opposite to that of the first rest position (the term "rest position" being understood to mean the position in which the magnet 182 is located after the motor 176 has executed the commanded series of three electrical pulses and then its rotor has stopped rotating).

[0129] Moreover, the actuator 174 comprises a bistable lever 184 pivoting about an axis 185 fastened to the mechanical movement and limited in its rotation by two pegs 188 and 189. The bistable lever comprises at its free end, which forms the head of the lever, a second bipolar magnet 186 which can be moved and substantially aligned with the first magnet 182, the magnetic axes of these two magnets being substantially collinear when the first magnet is in either of its two rest positions. Thus, with respect to the second magnet 186, the first rest position of the first magnet corresponds to a position of magnetic attraction, and the second rest position of the first magnet corresponds to a position of magnetic repulsion. Control signal S4 CmdHowever, each time the power supply circuit is activated to execute a series of three electrical pulses, the first magnet rotates half a turn and the lever passes alternately from a stable position in which it does not interact with the balance of the resonator to a stable position in which it does interact with the balance, and thus the lever 184 forms an abutment against the protrusion 190 against which the protrusion abuts when it reaches this head as the resonator vibrates and regardless of the direction of rotation of the balance at the moment of impact.

[0130] In the non-interacting position, the moving lever is outside the space traversed by the protrusion 190 when the resonator oscillates at an amplitude within its usable operating range. However, in the interacting position, the moving lever is partially located inside this space intersected by the protrusion, thus forming an abutment against the resonator. The term "stable position" is understood to mean a position in which the lever is maintained in both directions in the absence of any power supply from the motor 176 used to actuate the lever between its two stable positions. The lever therefore forms a bistable moving abutment against the resonator. This lever therefore forms a retractable stop member against the resonator. The actuator 174 is configured so that the lever can remain in the non-interacting position and the interacting position without maintaining power supply to the motor 176.

[0131] The stop member and the protrusion in their interacting positions are arranged to provide a first angular stop position θ relative to the balance of the vibrating resonator, which is different from the neutral position of the balance. B and the protrusion abuts against the stop member at this first angular stop position when it arrives from its angular position "0" corresponding to the neutral position of the resonator during the second half of the first determined half period of each oscillation period of the resonator. B is provided to be less than the minimum amplitude in the usable operating range of the vibrating mechanical resonator. Bis provided such that the oscillating resonator is stopped by a stop member outside the coupling zone between the oscillating resonator and the escapement of the mechanical movement. The stop member and the protrusion in their interacting position further define a second angular stop position for the balance of the oscillating resonator, close to but greater than the first angular stop position, when reached by the protrusion from the extreme angular position of the resonator during the first half of the second half period of each oscillation period. This second angular stop position is also provided to be less than the minimum amplitude in the usable operating range of the oscillating mechanical resonator.

[0132] In another alternative embodiment, it can be seen that the protrusion 190 extends axially from the outer edge or from one of the arms of the balance, and thus the bistable electromechanical device 174 is configured so that the bistable lever moves in a plane parallel to the axis of rotation of the balance. In this other alternative embodiment, the magnetization axes of the two magnets 182 and 186 are axial and remain substantially collinear, and therefore the magnet 182 is configured below the head of the lever. It can be seen that such a configuration of the bistable electromechanical device can also be provided with a protrusion extending radially from the outer edge within the scope of the alternative embodiment shown. It should be noted that in another alternative embodiment, the protrusion of the resonator can be configured around the staff of the balance, in particular around a plate supported by or integrally formed with this staff. In an alternative embodiment, such a plate is the plate that holds the escapement pins.

[0133] Finally, the timer 170 comprises an electronic control unit 196, which is associated with the optical sensor 192 and is configured to control the power supply circuit 178 of the electromechanical device, the unit 196 transmitting the control signal S4 Cmd The electronic control unit includes a control logic circuit 198, an up / down counter 200, and a clock circuit 202. The control unit and the external correction signal S ExtA receiver 204 for receiving the external correction signal S is associated with the electromechanical device 174, allowing the implementation of a second advance correction mode in addition to the second mode described below for correcting a delay in the time displayed by the timepiece's display. "Advance" and "delay" in the displayed time should be understood to refer both to errors detected by an external device with particular application to the present invention, and to jumps forward or backward in the displayed time. This jump, whether related to seasonal time changes as discussed above, or to a time zone change when the user of the timepiece moves from one time zone to another, can be detected by the external correction signal S. Ext The timer needs to be fed by an external device via

[0134] To implement the second correction mode implemented in this sixth embodiment, the electronic control unit 196 is configured to control an electromechanical device (also referred to as an "actuator" or "electromechanical actuator") to selectively actuate the stop member (bistable lever 184) depending on whether a delay or an advance is to be corrected in the time indicated by the timer, so that the stop member moves the protrusion 190 to the first angular stop position θ during the second half of the first half of the oscillation period, respectively. B and before the protrusion 190 reaches said second angular stop position during said first half-period of said second half-period of the oscillation period, the protrusion 190 is displaced from its non-interacting position to its interacting position.

[0135] In general, to at least partially correct the lead (positive time error), the electromechanical device is configured such that when the stop member is actuated to stop the mechanical resonator in the first half-period, the stop member momentarily prevents the mechanical resonator from continuing the natural oscillatory motion characteristic of this first half-period after the protrusion abuts against it, so that this natural oscillatory motion in the first half-period is momentarily interrupted and continues after a certain blocking time has elapsed due to the retraction of the stop member. Preferably, the case of a bistable electromechanical device as described above provides for the correction of substantially all of the positive time error determined by the correction external signal supplied to the timepiece according to the invention during successive blocking periods defining a correction period substantially equal to the lead to be corrected. To this end, in the alternative embodiment described, during the aforementioned second half of the oscillation period (the half period in which the protrusion 190 reaches the head of the lever 184 before the resonator passes its neutral position), i.e. during this second half period detected by the optical sensor 192 thanks to a configuration intended to detect the direction of the oscillatory motion during the detection of the passage of the resonator through its neutral position, after the moment the resonator passes its neutral position, the electronic control unit waits until a time T0c / 4 is reached and activates the actuator, via its motor, so as to drive the lever 184 from its non-interacting stable position to its interacting stable position, the head of the lever forming an abutment with the protrusion. Depending on the value of the angular stop, for example in the range 90° to 120°, a time shorter than T0c / 4, for example T0c / 5, is provided to initiate a series of three electrical pulses enabling the motor 176 to drive, thereby rapidly rotating its rotor by one and a half revolutions, thus extending the time interval enabling the lever to pivot between its two stable positions by reversing the direction of the magnetic flux generated by the magnet 182. In the latter case, it must be ensured that the protrusion actually exceeds the angular stop during the half-cycle preceding the first half-cycle in which the resonator is intended to be blocked during the correction period.

[0136] In general, the electromechanical device is configured such that when the stopping member is actuated to stop the mechanical resonator in the second half of at least one of the aforementioned first half periods of the oscillation period (which half period is the half period in which the protrusion 190 reaches the head of the lever 184 after the resonator has passed its neutral position) in order to at least partially correct the delay (negative time error), the stopping member therefore terminates this second half period early without interrupting the resonator but by reversing the direction of the oscillatory motion of this resonator, so that the mechanical resonator immediately begins the subsequent half period after being stopped instantly or almost instantly by the collision of the protrusion with the stopping member. Thus, within the second delay compensation mode, the detector for detecting the position and direction of movement of the resonator and the electronic control unit are configured to activate the actuator each time an external correction signal received by the receiver unit corresponds to a delay at the indicated time, whereby the actuator actuates its stop member so that a protrusion of the vibrating resonator abuts against said stop member in a number of half-cycles of the vibration of the mechanical resonator, terminating each of these half-cycles early without shutting down the mechanical resonator, each half-cycle following the passage of the resonator through the neutral position, the number of half-cycles in said number of half-cycles being determined by the delay to be compensated.

[0137] In a preferred alternative embodiment shown in Figures 17 and 18, the electronic control unit and the actuator, in order to at least partially compensate for the delay, after the lever is actuated from its non-interacting position to its interacting position when the vibrating resonator is located angularly to the neutral position with respect to the angular stop position, the lever is maintained in its interacting position until the end of a compensation period during which the protrusion of the vibrating mechanical resonator periodically abuts against the head of the lever multiple times, the duration of which is determined by the delay to be compensated for. The pivoting of the lever from its non-interacting position to its interacting position is preferably immediately after detecting passage through the neutral position, so that the protrusion is positioned at a stop angle θ B This can occur either in the first half-cycle, where the lever is in its interacting position before reaching θ (where the impact with the protrusion is intended to occur, this first half-cycle being detected by detecting the rotational direction of the balance), or in the second half-cycle, where the lever is in its interacting position (again detected by detecting the rotational direction of the balance) immediately after detecting the passage through the neutral position, this second alternative embodiment allowing more time to actuate the lever and allowing the lever to be stably placed in its interacting position (stop angle is by definition less than 180°). B = 120°, and the amplitude of free vibration of the resonator is θ L = 270°, in a second alternative embodiment, the angle θ relative to the axis of rotation defined by the head of the lever T When θ is equal to approximately 10°, a time interval corresponding to a rotation between the angle "0" and an angle slightly below 240° (360°-120°), i.e., 230°, is ensured to execute a pivoting of the lever (so as not to break the balance by exceeding the position of the protrusion in the second half-period), whereas in the first alternative embodiment, a time interval corresponding only to a rotation between the angle "0" and 120° is obtained. L <360°-θ B -θ TIf so, it can be seen that in the second alternative embodiment, more time is available for pivoting the lever.

[0138] Typically, to determine the duration of the lag correction period, the electronic control unit comprises a measurement circuit associated with the optical sensor, said measurement circuit comprising a clock circuit providing a clock signal at a given frequency and a comparator circuit making it possible to measure the time drift of the oscillating resonator relative to its setpoint frequency, the measurement circuit being configured to measure the time interval from the beginning of the correction period corresponding to the time drift of the mechanical resonator, the electronic control unit being configured to terminate the correction period as soon as said time interval is equal to or slightly greater than the time error introduced by the external correction signal.

[0139] In an alternative embodiment depicted in Figure 16, the measurement circuit comprises a clock circuit 202 providing a periodic digital signal at a frequency F0c / 2, and an up / down counter 200 (a reversible counter). This up / down counter receives at its "-" input the periodic signal of the clock circuit (which decrements the counter by two units every setpoint period T0c = 1 / F0c), and at its "+" input the digital signal from the optical sensor 192, which comprises a pulse or change of logic state each time the resonator 14A passes through its neutral position "0". Since such a passage occurs every half period of the vibrating resonator, the counter 200 increments by two units every oscillation period. Thus, the counter (an integer M Cb ) represents the time drift of the mechanical resonator relative to a setpoint frequency determined by a clock circuit with the precision of a quartz oscillator. Cb corresponds to the number of additional half-cycles performed by the resonator from the initial moment the invertible counter is reset for the case of oscillation at the setpoint frequency.

[0140] The control logic circuit 198 receives digital signals from the optical sensor 192, which enable it to determine the passages of the resonator through its neutral position and the direction of the oscillatory motion at each of these passages. To correct a given delay, after the passages of the resonator through its neutral position have been detected as described above, the control logic circuit activates, on the one hand, the actuator 174 to actuate the lever to its interacting position, and, on the other hand, activates the clock circuit 202 and the up / down counter 200, which determine the beginning of the correction period. It should be noted that in an alternative embodiment, this reset can be performed before powering the actuator 174 to pivot the lever, but after the electronic control unit 196 and the optical sensor 192 have been activated. According to an alternative embodiment, a reset of the clock circuit is not provided for this purpose. In other alternative embodiments, the optical sensor is replaced by another type of sensor, for example a magnetic or capacitive type. In a particular alternative embodiment, the detector that detects the passage of the mechanical resonator through its neutral position is formed by a miniaturized acoustic sensor (a microphone of the MEMS type) capable of detecting the acoustic pulse generated by the impact between the pin of the balance and the fork of the pallet-lever that forms the escapement of the mechanical movement.

[0141] Negative time error T Err The number of half periods at the setpoint frequency F0c (for a given delay) is -T Err 2F0c. Therefore, the number of up / down counters M Cb As soon as this value is reached or slightly exceeded (since this value is not necessarily an integer), the given delay is corrected and the displayed time is accurate again (thus giving a precise real time, specifically to an accuracy of one second). Therefore, the control logic changes the state of the counter to the value -T Err 2·F0c, and the number M Cbis greater than or equal to this value, the power supply circuit 178 to the actuator is controlled so that the actuator terminates the correction period by actuating the lever from its interacting stable position to its non-interacting stable position.

[0142] 17 and 18 respectively show the vibration of the resonator 14A at the beginning of a period for correcting a given delay for two particular extreme cases of the preferred alternative embodiment described above. FIG. 17 relates to the case where the kinetic energy of the resonator is completely absorbed between the balance prong and the abutment head during each impact. In particular, the free vibration 210 continues for a second free half-cycle A2 before detecting time t0 at the moment the resonator passes through its neutral position (position "0" of the prong 190) in the first subsequent half-cycle. L , where time t0 indicates the start of the period for correcting a given delay. The lever is displaced to its interacting position immediately after time t0. After the first impact between the protrusion and the lever, a relatively large positive phase difference DP1 is obtained between the fictitious free oscillation 211 and the oscillation 212. At that time, a stable phase is established, in which the oscillation 212 is shortened relative to the fictitious free oscillation 213 due to the stopping of the preceding resonator by the stopping member in the second half period of the first half period A1 of each oscillation period, thus resulting in a positive phase difference DP2 smaller than DP1. The second half period A2 of the oscillation 212 is not disrupted by the lever.

[0143] FIG. 18 relates to the special case of a strong impact or elastic collision between the protrusion and the head of the lever. In this case, assuming that there is no dissipation of kinetic energy during the impact and only a reversal of the direction of the oscillatory motion, the kinetic energy of the resonator is preserved during each impact. Therefore, the amplitude of the oscillation 216 during the correction period remains the same for each oscillation period as the amplitude of the free oscillation 210 and, therefore, the amplitude of the fictitious free oscillation 217. After time t0, a stable phase is established with half periods A1* and A2* having a duration T2 much smaller than T0 / 2, resulting in a relatively large positive phase difference DP3 in each oscillation period. To achieve an elastic collision, the lever can be considered to have a certain elasticity; specifically, the body and / or head of the lever can be formed by an elastic material capable of being subjected to a certain degree of compression so as to momentarily absorb the kinetic energy of the balance and redistribute it shortly after the oscillatory motion reverses. In such a case, the oscillation 216 is stopped at a stop angle θ B In another, more sophisticated alternative embodiment, it is a protrusion that is resiliently mounted on the outer edge of the balance. For example, the protrusion has a base that forms a slide arranged in a circular sliding surface machined into the outer edge, and when the protrusion is in its angular position "0", a resilient element, in particular a small helical spring, is arranged behind the slider, i.e. in the sliding surface on the opposite side of the protrusion from the head of the lever. In practice, the impact between the protrusion of the balance and the abutment of the electromechanical device usually occurs in a manner that corresponds to a physical situation between the two extreme situations described in Figures 17 and 18.

[0144] Finally, in another embodiment, the electromechanical device is formed by a monostable electromechanical actuator, which comprises a movable finger configured in such a way that when the actuator is not activated (no power is applied) and when it is activated (i.e. power is applied), the movable finger can be displaced alternately between a first radial position and a second radial position, respectively. The first radial position of the finger corresponds to a position in which it does not interact with the balance of the vibrating resonator, and the second radial position of the finger corresponds to a position in which it interacts with the balance of the vibrating resonator, thus forming an abutment for the protrusion of the vibrating balance, similar to the head of the lever 184.

Claims

1. - a display (12) for showing the actual time; a mechanical movement (4; 4A; 92) comprising a drive mechanism (10) for said display and a mechanical resonator (14; 14A) linked to said drive mechanism, the vibrations of which time the operation of said drive mechanism; - a device for correcting the actual time displayed by the display; In a timepiece (2; 112; 132; 154; 170) comprising: - said device for correcting the actual time displayed, - an external correction signal (S Ｅｘｔ a receiver unit (30, 30A; 30B; 204) for receiving the - an electronic control unit (28, 28A; 28B; 196), and a damping device (22; 22A; 22A, 106; 22B, 114; 24C, 26C; 22C; 174) for damping said mechanical resonator; formed by a timepiece (2; 112; 132; 154; 170), characterized in that the electronic control unit is configured to process information contained in the external correction signal and to control the braking device as a function of said information, and the device for correcting the actual time is configured so that when the external correction signal received by the timepiece requires a correction of the actual time to be displayed, the braking device acts on the mechanical resonator during a correction period and modifies the operation of the drive mechanism to perform at least one major part of the required correction.

2. 2. A timepiece according to claim 1, comprising a device (144; 192) for determining the passage of the vibrating mechanical resonator through at least one specific position, wherein the device (144; 192) for determining the passage of the vibrating mechanical resonator enables the electronic control unit to determine a specific moment at which the vibrating mechanical resonator is at said specific position, and wherein the electronic control unit is configured such that a first activation of the braking device, which occurs at the start of the correction period and generates a first interaction between the braking device and the mechanical resonator, is initiated as a function of said specific moment.

3. The mechanical movement comprises an escapement associated with the mechanical resonator, and the braking device comprises an actuator (174) provided with a stop member (184) for stopping the oscillating mechanical resonator, the stop member being operable between a position where it does not interact with the mechanical resonator and a position where it interacts with the mechanical resonator, the stop member forming an abutment for a protrusion (190) of the oscillating mechanical resonator, the protrusion being configured to abut against the stop member when the stop member is in the interaction position with the protrusion, and the stop member in the interaction position and the protrusion being configured to abut against the stop member when the stop member is in the interaction position with the protrusion, and Ｂ ), the neutral position corresponds to a minimum potential energy state of the mechanical resonator, the stop position is less than a minimum amplitude of the vibrating mechanical resonator in the available operating range of the mechanical resonator, and the stop position is determined by the stop member so that the vibrating mechanical resonator is within a coupling zone (θ ＺＩ ) and the device for determining the passage of the vibrating mechanical resonator is further provided to be stopped outside of the external correction signal (S Ｅｘｔ 3. The timepiece of claim 2, wherein the actuator can be activated when a delay in the displayed time to be corrected corresponds to a delay in the displayed time, whereby the actuator actuates the stop member of the actuator so that the protrusion (190) of the vibrating mechanical resonator abuts against the stop member (184) for a plurality of half-cycles of the vibrating mechanical resonator, each half-cycle following the passage of the mechanical resonator through the neutral position, to terminate each half-cycle early without shutting down the mechanical resonator, wherein the number of half-cycles of the plurality of half-cycles or the duration of the correction period during which the stop member is held in the interacting position is determined by the delay to be corrected.

4. The device for determining the passage of the vibrating mechanical resonator comprises a detector (192) for detecting the position and direction of motion of the mechanical resonator, the detector and the mechanical resonator being configured such that the vibrating mechanical resonator detects the passage of the vibrating mechanical resonator through the specific position ("0") in each of its periods of vibration, and the electronic control unit (196) determines the direction of motion of the vibrating mechanical resonator in the half period in which the passage of the vibrating mechanical resonator through the specific position is detected, the electronic control unit being configured such that the electronic control unit determines the direction of motion of the vibrating mechanical resonator in each half period in which the passage of the vibrating mechanical resonator through the specific position is detected, 4. The timepiece of claim 3, wherein the actuator is configured to at least partially compensate for the delay by controlling a vibrating mechanical resonator (174), whereby, when the vibrating mechanical resonator is located on the side of the neutral position with respect to the stop position, the actuator actuates the stop member of the actuator from a position where it does not interact with the stop member to a position where it interacts with the stop member, whereby the actuator subsequently holds the stop member in the interacting position for a determined duration sufficient for the protrusion of the vibrating mechanical resonator to abut against the stop member at least once.

5. 5. The timepiece according to claim 4, wherein the actuator (174) is of a bistable type and is configured to be able to remain in the non-interacting position and the interacting position without maintaining power supply to the actuator, and wherein the electronic control unit and the actuator are configured such that, when the oscillating mechanical resonator is located on the side of the neutral position with respect to the stop position, the stop member (184) is maintained in the interacting position of the stop member after the stop member is actuated from the non-interacting position of the stop member to the interacting position of the stop member until the completion of the correction period during which the protrusion (190) of the oscillating mechanical resonator periodically abuts against the stop member multiple times, in order to at least partially correct the delay.

6. 6. A timepiece according to claim 4 or 5, characterized in that the electronic control unit comprises a measurement circuit, the measurement circuit being associated with the detector, the measurement circuit comprising: a clock circuit (202) providing a clock signal at a determined frequency (F0c / 2); and a comparator circuit (200) making it possible to measure the time drift of the oscillating mechanical resonator relative to its setpoint frequency (F0c), the measurement circuit being adapted to measure a time interval corresponding to the time drift of the mechanical resonator from the start of the correction period, the electronic control unit being adapted to terminate the correction period as soon as said time interval is equal to or greater than the time error provided by the external correction signal.

7. The braking device is formed by electromechanical actuators (22, 22A; 22B; 22C; 24C and 26C) configured to be able to apply braking pulses to the mechanical resonator, and the electronic control unit is configured to apply a braking pulse at a frequency F ＳＵＰ A first periodic digital signal (S ＦＳ， S ＦＳ１， S ＦＳ２， ) derived from the first periodic digital signal when the external correction signal received by the receiver unit corresponds to an indicated time delay to be corrected. Ｃ１ , S Ａｃｔ (S ＦＳ ), S1 Ｃｍｄ (S ＦＳ１， S ＦＳ２ )) to the damping device during a first correction period to activate the damping device, whereby the damping device applies a first series of periodic damping pulses to the mechanical resonator at the frequency F ＳＵＰ the duration of the first correction period and therefore the number of periodic braking pulses in the first series is determined by the delay to be corrected, and the frequency F ＳＵＰ the first series of periodic braking pulses at frequency F can be in a first synchronization phase during the first correction period. ＳＵＰ is provided, and the damping device is configured so that the vibration of the mechanical resonator (14) is regulated by a correction frequency FS which is greater than a setpoint frequency F0c provided to the mechanical resonator. Ｃｏｒ 2. The timepiece of claim 1, wherein the timepiece is synchronized with a timestamp.

8. The frequency F ＳＵＰ has at least two different values ​​F1 as a function of the delay to be corrected. ＳＵＰ and F2 ＳＵＰ and said device for generating at least one frequency may have a frequency F1 ＳＵＰ and frequency F2 ＳＵＰ a frequency generating device configured to generate a selection of the first periodic digital signal at a frequency F1 ＳＵＰ and frequency F2 ＳＵＰ is the correction frequency FS Ｃｏｒ However, the frequency F1 ＳＵＰ and the frequency F2 ＳＵＰ Two different values ​​F1 Ｃｏｒ and F2 Ｃｏｒ and F2 Ｃｏｒ is F1 Ｃｏｒ is greater than the frequency F1 ＳＵＰ is selected if the delay is less than a given value, while the frequency F2 ＳＵＰ 8. The timepiece of claim 7, wherein is selected if the delay is greater than or equal to the given value.

9. The device for generating at least one frequency is ＩＮＦ A second periodic digital signal (S ＦＩ ) and the electronic control unit (28B; 28C) is configured to generate a second control signal (S) derived from the second periodic digital signal when the external correction signal received by the receiver unit corresponds to the indicated time advance to be corrected. Ａｃｔ (S ＦＩ ), S1 Ｃｍｄ (S ＦＩ )) to the damping device during a second correction period to activate the damping device, whereby the damping device applies a second series of periodic damping pulses to the mechanical resonator at the frequency F ＩＮＦ the duration of the second correction period and therefore the number of periodic braking pulses in the second series is determined by the advance to be corrected, and the frequency F ＩＮＦ the second series of periodic braking pulses at frequency F can be in a second synchronization phase during the second correction period. ＩＮＦ is provided, and the damping device is configured so that the vibration of the mechanical resonator is damped at a correction frequency FI which is less than the setpoint frequency F0c provided to the mechanical resonator. Ｃｏｒ 9. A timepiece according to claim 7 or 8, characterized in that it is synchronized with

10. The mechanical movement comprises an escapement associated with the mechanical resonator, and the frequency F of the braking pulses of the first series of periodic braking pulses ＳＵＰ and the duration of the first correction period is such that, during the first synchronization phase, each of the braking pulses of the first series is equal to the coupling zone (θ ＺＩ 9. A timepiece according to claim 7 or 8, characterized in that the time is selected to occur outside of the period

11. The mechanical movement comprises an escapement associated with the mechanical resonator, and the frequency F of the braking pulses of the second series of periodic braking pulses ＩＮＦ and the duration of the second correction period is such that, during the second synchronization phase, each of the braking pulses of the second series is applied to the coupling zone (θ ＺＩ 10. The timepiece of claim 9, wherein the time is selected to occur outside of the time period t1.

12. The device for generating at least one frequency generates a third periodic digital signal (S Ｆ０ｃ ) and the electronic control unit is configured to generate a third control signal (S Ａｃｔ (S Ｆ０ｃ ), S1 Ｃｍｄ (S Ｆ０ｃ ) to the braking device during a preliminary period preceding the correction period to activate the braking device and cause the braking device to generate a preliminary series of periodic braking pulses and apply the series to the mechanical resonator at the setpoint frequency F0c, wherein the duration of the periodic braking pulses and the braking force applied to the oscillating mechanical resonator during the preliminary series of periodic braking pulses are such that none of the braking pulses drives the oscillating mechanical resonator beyond a coupling zone (θ ＺＩ the electronic control unit is configured to synchronize the oscillation of the mechanical resonator to the setpoint frequency F0c and to generate a preliminary synchronization phase at least at the end of the preliminary period, the electronic control unit is configured to synchronize the oscillation of the mechanical resonator to the setpoint frequency F0c and to generate a preliminary synchronization phase, the electronic control unit is configured to synchronize the oscillation of the mechanical resonator to the setpoint frequency F0c and to generate a preliminary synchronization phase, the electronic control unit is configured to synchronize the oscillation of the mechanical resonator to the setpoint frequency F0c and to generate a preliminary synchronization phase at least at the end of the preliminary period ... Ｃｏｒ 9. A timepiece according to claim 7 or 8, characterized in that the first synchronization phase in is provided to start immediately at the first braking pulse or the second braking pulse.

13. 9. A timepiece according to any one of claims 1 to 5, 7 and 8, comprising a device (22; 106; 114; 174) for blocking the mechanical resonator, wherein the electronic control unit is configured to be able to supply a fourth control signal to the blocking device when the external correction signal received by the receiver unit corresponds to a displayed time advance to be corrected, the fourth control signal activating the blocking device so that the blocking device blocks the oscillation of the mechanical resonator during the correction period, the correction period being determined by the advance to be corrected, so as to terminate the operation of the drive mechanism during the correction period.

14. 14. A timepiece according to claim 13, characterized in that the correction period has a duration substantially equal to the advance to be corrected.

15. 14. The timepiece according to claim 13, characterized in that the interrupting device is formed by a device (114) separate from the braking device and comprises a bistable lever (115), a first stable position of which corresponds to a position for not interacting with the mechanical resonator and a second stable position of which corresponds to a position for stopping and interrupting the mechanical resonator.

16. 14. A timepiece according to claim 13, characterized in that, when the isolating device is activated to shut off the mechanical resonator during the period for correcting a given advance, the isolating device (106) forms a lock on the mechanical resonator, and a part (107) of the isolating device is inserted into a cavity (108) configured in a circular element (100) of a balance forming the mechanical resonator.

17. 9. A timepiece according to any one of claims 1 to 5, 7 and 8, characterized in that the correction of the displayed time is for a time error detected in the displayed time by an external device capable of supplying the external correction signal to the timepiece.

18. 9. A timepiece according to any one of claims 1 to 5, 7 and 8, characterized in that the correction of the displayed time is for a change of time zone or a change of seasonal time.

19. 19. A timepiece according to claim 18, further comprising a measuring circuit formed by a programmable counter and a clock circuit, for measuring the remaining time interval between the receipt of an external correction signal for a seasonal time change and the date and time scheduled for said seasonal time change.

20. 9. An assembly formed by a timepiece according to any one of claims 1 to 5, 7 and 8, and an external device (40; 152) comprising a transmitter (52) for transmitting the external correction signal, said external device comprising: a photographic device (44; 1156) comprising a photographic sensor formed by an array of photodetectors; an image processing algorithm configured to be able to determine the position of at least one determined hand of said indicator of said timepiece in the image captured by said photographic device; a time base (48) capable of providing an accurate actual time used to generate the external correction signal for correcting the actual time displayed by the display; An assembly comprising:

21. 21. The assembly according to claim 20, wherein the external device (40; 152) further comprises an algorithm for calculating a time error between first time data and second time data, the first time data being displayed by the display at a given time instant and detected by the external device via its photo sensor and the image processing algorithm, and second time data corresponding to the first time data and being supplied by the time base substantially at the given time instant, and wherein when the assembly intends to correct the determined time error, the external correction signal supplied by the external device (40; 152), external to the timer, contains information related to the time error.

22. 21. The assembly according to claim 20, characterized in that the external device is a mobile phone (40).

23. 21. The assembly according to claim 20, characterized in that the external device is incorporated in a housing (152), the housing (152) being provided for the timer and comprising a recess for receiving the timer (154) at a given position.

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