Energy injection type rate control method and device for mechanical timepieces

Abstract

To control the rate of a mechanical watch with high precision. [Solution] In mechanical watches, A sensor detects the vibrations of the balance, and the cumulative frequency is compared with the clock cumulative frequency of the reference oscillator to calculate the rate error. Based on this error, a control method is determined, and mechanical energy is injected into the balance by an actuator to control the rate. For even more precise control, abnormal vibrations are recorded to evaluate the reliability of the measurements and adjust the control strategy accordingly. In addition, if sensor detection is difficult, it is supplemented by phantom counts estimated from the reference oscillator. If necessary, it is also possible to identify external factors using auxiliary sensors. When high reliability is required, sensors with different detection principles can be duplicated and cross-verified. This configuration enables implementation at various levels, from basic rate control to advanced adaptive control.

Description

[Technical Field]

[0001] The present invention relates to a control technology for maintaining the rate of a mechanical timepiece with high precision, and in particular to a control method and device for detecting the vibration of the balance wheel, comparing it with an internal reference oscillator, and injecting energy into the balance wheel as necessary to adjust the rate. [Background technology]

[0002] Maintaining high accuracy in mechanical watches is a perpetual technical challenge. In recent years, the use of new materials has improved temperature characteristics and magnetic resistance, but new challenges have also arisen. For example, while silicon balance springs have excellent properties, they are difficult to fine-tune after manufacture. Furthermore, in modern society, where devices that generate strong magnetic fields (smartphones, tablets, magnetic clasps, etc.) are readily available, the magnetic resistance of watches is becoming increasingly important, necessitating the development of control systems that are less susceptible to the effects of magnetic fields.

[0003] In conventional mechanical watches, the following adjustment means have been used. (1) Adjustment method using the regulator The most common method of adjusting the oscillation period is to change the effective length of the balance spring, but this has a limited range and requires skill. (2) Means for adjusting the moment of inertia This method uses adjustment screws and weights to change the balance's moment of inertia. Fine adjustments are possible, but it is difficult to dynamically adjust to changes in position or temperature. (3) Means for adjusting the bending of the hairspring This is possible with metal balance springs, but is virtually impossible with brittle materials such as silicon.

[0004] On the other hand, the following methods have been proposed as methods for improving accuracy using electronic technology. (1) Electromagnetic brake system This system uses a quartz oscillator as a reference to monitor the rotation of the gear train, and if it goes too fast, it slows down with an electromagnetic brake. This is inefficient because it consumes energy, and it cannot handle delays. (2) Escapement locking system This is a protection mechanism that physically locks the escapement when abnormal vibration is detected. It requires additional mechanical parts and makes the structure more complex. (3) Long period correction method This method measures and corrects the rate over a period of several hours or days, and cannot handle short-term fluctuations.

[0005] Patent Document 1 describes a technique that utilizes the energy transport properties of light or lasers into the inside of a watch case in order to reversibly deform a partial region of a vibrator. However, the current state of the oscillator is not grasped, and adjustment is not performed by comparing it with a reference phase or cumulative frequency. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2017-026607 Summary of the Invention [Problem to be solved by the invention]

[0007] The above-mentioned conventional techniques have the following problems. (1) Limits of adjustment Mechanical adjustments have limitations in their range and precision. Even after adjustment, the rate can fluctuate depending on environmental conditions. New materials (such as silicon) make physical adjustments difficult or impossible. (2) Energy efficiency Braking systems are inefficient, consume energy, and do not compensate for delays. (3) Complexity of structure Adding a locking mechanism increases the number of parts, making the movement thicker and increasing manufacturing costs. (4) Lack of responsiveness Long-period correction cannot keep up with daily fluctuations, and it is difficult to respond immediately to changes in posture or temperature.

[0008] The object of the present invention is to provide a method and apparatus for controlling rate with high precision and efficiency by constantly monitoring the oscillations of the balance and injecting energy based on a comparison with a reference oscillator, while minimizing the need for additional mechanical mechanisms. Furthermore, in order to cope with modern magnetic field environments, the sensor configuration is designed to be less susceptible to magnetic field influences, and the reliability of measurements is evaluated as necessary to perform adaptive control, thereby achieving more stable and highly accurate rate control. [Means for solving the problem]

[0009] In a first aspect of the present invention, there is provided a method for controlling the rate of a mechanical timepiece, comprising: a) a vibration detection and accumulation step in which a sensor detects the vibrations of the balance and records the cumulative number of vibrations since the start of measurement; b) a reference comparison step of comparing the clock cumulative count of a built-in reference oscillator with the vibration cumulative count to calculate a deviation from an ideal rate; c) an energy injection step of injecting mechanical energy into the balance using an actuator according to the determined control method; A control method is provided, comprising: Here, the method may further include a control method determination step of determining a control method for energy injection based on the comparison result.

[0010] Furthermore, for more precise control, the following functions may be included. (1) Measurement reliability evaluation function Vibrations that deviate from the normal vibration pattern (out-of-step beats) are recorded, and the reliability of the measured values ​​is evaluated based on the occurrence rate and stability of the vibrations.More stable control can be achieved by dynamically changing the control policy depending on the reliability. (2) Compensation function when detection is not possible If no detection is performed by the sensor, the count is supplemented by a virtual frequency (hereinafter referred to as a phantom count) estimated from a reference oscillator and past vibration history. (3) Factor identification function using auxiliary sensors If necessary, information from auxiliary sensors is utilized to distinguish between external and internal factors. (4) Mutual verification function by dual sensors When high reliability is required, two sensors with different detection principles are used and cross-validation is carried out to improve the certainty of detection. These configurations enable implementation at various levels, from basic rate control to advanced adaptive control that takes into account measurement errors and disturbances. [Effects of the Invention]

[0011] According to the configuration of the present invention, one of the following effects can be obtained. (Effect 1) Improved accuracy Constant comparison with a reference oscillator achieves precision exceeding that of conventional mechanical adjustments. Energy injection makes it possible to handle both lead and lag. (Effect 2) Simplicity of structure No mechanical locking mechanism is required. Easy to apply to existing movements. (Effect 3) Improved energy efficiency Energy can be injected when and as much as needed. There is no braking loss. (Effect 4) Versatility It can be used regardless of the material of the hairspring. It is compatible with various sensor methods. The use of an optical sensor achieves excellent magnetic resistance.

[0012] Furthermore, by adding a reliability evaluation function, one of the following effects can be expected. (Effect 5) High accuracy and stability Adaptive control based on measurement reliability enables stable control that is resistant to external disturbances, and ultra-high accuracy on the level of monthly deviations can be achieved. (Effect 6) Effects of adding self-diagnosis function By recording the out-of-step beat, the condition of the movement can be ascertained, making it possible to determine when maintenance is required. (Effect 7) Tolerance to detection failures The phantom counting function can suppress cumulative errors even in the event of temporary detection failure. The auxiliary sensor makes it possible to distinguish between true abnormalities and external factors. The dual sensor configuration ensures tolerance to single failures. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a schematic diagram showing the state in which the rate control device of this embodiment is incorporated into the main body of a mechanical timepiece. [Figure 2] FIG. 2 is a schematic diagram showing the configuration and fixed arrangement of the actuator. [Figure 3] FIG. 3 is a functional block diagram showing the functional configuration of the control unit. [Figure 4] FIG. 4 is a flowchart showing the control flow of the control unit. [Figure 5] FIG. 5 is a schematic diagram showing the state in which the watch rate control device of this embodiment is incorporated into the main body of a mechanical watch. [Figure 6] FIG. 6 is a functional block diagram showing the functional configuration of the control unit. [Figure 7] FIG. 7 is a flowchart showing the control flow of the control unit. DETAILED DESCRIPTION OF THE INVENTION

[0014] The configurations, arrangements, element selections and various values ​​shown in the following examples are merely examples, and are not limited to these and may be changed as appropriate. [Example]

[0015] FIG. 1 is a schematic diagram showing the state in which the watch rate control device of this embodiment is incorporated into a mechanical timepiece body 100. The rate control device of the present invention is configured as a system comprising an oscillator 110, an actuator 120, a sensor unit 130, a control unit 140, an external reference clock 150, and a power supply unit 160, which are also components of a mechanical timepiece body 100. The sensor unit 130 is built into the mechanical timepiece body 100 , detects the vibration of the balance wheel of the oscillator 110 , and transmits a detection signal to the control unit 140 . The control unit 140 is electrically connected to the other components to receive detection signals, send control signals, and control the supply of power. The external reference clock 150 is an external transmitter that incorporates an oscillator that vibrates separately from the balance that constitutes the mechanical timepiece, and transmits a reference clock signal, which is the oscillation signal, to the control unit 140. The power supply unit 160 is made up of a button battery (1.55V), a DC-DC booster that boosts the voltage of the button battery to 10V, and a current monitor that monitors the average current I_avg.

[0016] Actuator 120 is attached to vibrator 110. Reference numeral 111 denotes the vibrator's hole, and 112 denotes the vibrator's main vibration axis. Actuator 120, which consists of two electronic actuators, is fixed to hole 111. Actuator 120 is arranged in a direction (referred to as the X-axis) perpendicular to the vibrator's main vibration axis (referred to as the Z-axis), and is composed of a pair of electronic actuators each having position vectors r1 and r2 as viewed from the main vibration axis. These actuators can apply forces F1 and F2 in opposing directions along the X-axis, and a rotational torque component about the main vibration axis is generated by the cross product of each force vector and the position vector. This minute vibration energy in the orthogonal direction is transferred to the main vibration along the main vibration axis via mechanical cross-axis coupling.

[0017] FIG. 2 is a schematic diagram showing the configuration and fixed arrangement of the actuator. Two electronic actuators 201 and 202 are fixed to the hole stone 111 of the vibrator 110 so as to sandwich both shoulders of the vibrator's main vibration axis 112, and the displacement axis of each electronic actuator is set at a position where it abuts against the shoulder of the main vibration axis 112 with a slight preload at an inclination angle α (0°<α<90°) with respect to the XY plane, which is the rotation plane of the balance wheel. At the contact points with the main vibration axis 112, the electronic actuators 201 and 202 are displaced in the directions of their respective displacement axes 203 and 204 to apply a pulse external force.

[0018] Here, an electronic actuator is used as the actuator, which transfers vibration energy in the orthogonal direction to the main vibration along the main vibration axis via a mechanical cross-axis coupling, but the actuators that can be used in the present invention are not limited to this, and the fixed arrangement method and the actuator body can be changed as appropriate, such as using a fixed arrangement method in which a single actuator is provided so that it can be displaced in the tangential direction of the outer periphery of the balance wheel instead of the mechanical cross-axis coupling method, or using an electrostatic actuator, shape memory alloy actuator, electromagnetic coil, or micromachine actuator instead of the electronic actuator.

[0019] (sensor unit) A single CMOS optical motion sensor is used for the sensor unit 130. The sensor pulse-drives a specified VCSEL (Vertical-Cavity Surface-Emitting Laser) and performs correlation calculations on the scattered light pattern with a light-receiving pixel array to obtain vibration data including the zero-crossing interval of the angular velocity and the frequency and amplitude of the balance wheel, and transfers the data to the control unit.

[0020] Here, an infrared reflective optical sensor is used as the sensor that constitutes the sensor unit, but the sensors that can be used in the present invention are not limited to this, and non-magnetic response sensors that are less susceptible to magnetic fields, such as high-sensitivity reflective optical sensors, transmission optical sensors, high-resolution optical encoders, capacitance sensors, and piezoelectric sensors, can be appropriately used. This makes it possible to prevent a decrease in detection accuracy and malfunction even when a magnetic field is present in the surrounding environment.

[0021] (control unit) The operation of each functional component shown here is realized by executing a control program such as pre-installed firmware on a specified processor or dedicated hardware circuit, and by cooperating with various devices that constitute the device. The control unit 140 compares the phase and cumulative frequency of the oscillator with a reference clock from an external reference source 150, and realizes phase synchronization control using the phase difference and cumulative frequency difference as inputs.

[0022] A microcontroller unit (hereinafter referred to as MCU) is employed for the control unit 140. The MCU monitors the state of the vibrator in real time by referring to an external reference signal, and executes control processing based on proportional-integral PI control (hereinafter referred to as PI control). That is, the MCU calculates the phase difference ΔΦ between the current phase of the oscillator and the reference signal in real time, derives a correction amount proportional to this ΔΦ, and instantly adjusts the pulse injection timing (P control). In addition, the cumulative frequency difference ΔN between the oscillator and the reference signal is calculated, and the control parameters such as the total amount and width of pulse injection are adjusted by integrally reflecting the correction amount based on ΔN so that this ΔN becomes zero (I control). This allows the MCU to dynamically control the injection amount and injection timing of the pulse external force output to the pulse generator, and synchronize the frequency and phase of the oscillator with an external reference.

[0023] FIG. 3 is a functional block diagram showing the functional configuration of the control unit. The control unit 140 is generally composed of a control unit 301 and a pulse generator 309 that outputs a pulse external force control command in accordance with a pulse control profile and a drive trigger generated by the control unit. The control unit 301 is composed of a sensor signal processing unit 302, a real vibration counter 303, a reference vibration counter 304, a phantom count generation unit 305, a recording unit 306 that records log information of past vibration states, a comparison unit 307, and a control policy determination unit 309.

[0024] The sensor signal processing unit 302 detects the vibration state of the balance based on the signal obtained from the vibration sensor, generates a detection signal corresponding to the periodic displacement of the vibration, and sends it to the real vibration counter 303. The vibration state includes the frequency and amplitude of the vibration.

[0025] Every time a detection signal is received, the real vibration counter 303 increments the cumulative real vibration number up to that point, and sequentially records the number of vibrations since the start of measurement.

[0026] If the phantom count generator 304 cannot receive a detection signal from the sensor signal processor 302 within a predetermined time, it refers to log information on past vibration states stored in the recorder 306 and generates a phantom count signal that simulates a periodic displacement similar to that of real vibration based on the vibration period and amplitude recorded in the log. The generated phantom count signal is sent to the real vibration counter 303 and processed in the same way as a normal detection signal. Here, the timing of the next vibration is predicted from the average period of the past 10 vibrations, and a phantom count is generated, thereby maintaining stable control even if the detection rate temporarily drops. This operation virtually counts the number of vibrations estimated from the external reference clock and past vibration history, even when no vibration is detected. This prevents the cumulative error from increasing even if the sensor temporarily fails to detect the vibration or misses a detection due to a decrease in amplitude.

[0027] Each time the reference vibration counter 305 receives a reference clock signal from the reference clock, it increments the cumulative number of reference vibrations up to that point, and sequentially records the number of vibrations since the start of measurement.

[0028] The recording unit 306 records log information on the vibration state of the transducer, log information on the generation of the phantom count signal, and log information on the step-out count of the transducer.

[0029] The comparison unit 307 compares the current phase of the oscillator with the phase of the reference clock signal to calculate the phase difference ΔΦ, and also compares the accumulated real frequency stored in the real frequency counter with the accumulated reference frequency stored in the reference frequency counter to calculate the accumulated frequency difference ΔN.

[0030] The control policy determination unit 308 performs proportional control based on the phase difference ΔΦ detected in real time, and generates basic parameters of a pulse control profile and a drive trigger using a correction amount proportional to the phase difference (P control). Furthermore, integral control is performed based on the cumulative frequency difference ΔN, and a correction amount corresponding to the cumulative error is added to the basic parameters, thereby correcting the long-term frequency deviation (I control). The control parameters thus obtained are sent to the pulse generator 309 and are used to inject external force pulses by the actuator.

[0031] The pulse generator 309 transmits a pulse external force control command to the actuator in accordance with the control parameters generated by the control policy determination unit 308 .

[0032] (Control Flow) FIG. 4 is a flowchart showing the control flow of the control unit. In step A1, the control unit detects the vibration state of the vibrator from the sensor signal. In step A2, the control unit obtains the cumulative real vibration number from the real vibration counter. In step A3, the control unit compares the current phase of the oscillator with the phase of the reference clock signal to calculate the phase difference ΔΦ, and also compares the accumulated real frequency stored in the real vibration counter with the accumulated reference frequency stored in the reference vibration counter to calculate the accumulated frequency difference ΔN.

[0033] In step A4, proportional control is performed based on the phase difference ΔΦ detected in real time by the control unit, and a correction amount proportional to the phase difference is used to generate a pulse control profile and basic parameters of a drive trigger (P control). Furthermore, integral control is performed based on the cumulative frequency difference ΔN, and a correction amount corresponding to the cumulative error is added to the basic parameters, thereby correcting the long-term frequency deviation (I control).

[0034] In step A5, the control unit generates a pulse external force command from the control parameters obtained in step A4 and outputs it to the pulse generator. In step A6, the pulse generator drives the actuator and injects an external force pulse into the main vibration axis of the vibrator.

[0035] In step A7, the operations from A1 are repeated. In this way, while PI control is the basic configuration, loop control is performed and synchronization with an external reference is executed. [Example]

[0036] The second embodiment is an embodiment relating to a high reliability configuration (dual sensors) when higher detection reliability is required. In the following description, the same configurations and operations as those in the first embodiment will be omitted as appropriate.

[0037] FIG. 5 is a schematic diagram showing the state in which the watch rate control device of this embodiment is incorporated into a mechanical timepiece body 500. The rate control device of the present invention is configured as a system comprising an oscillator 510 , an actuator 520 , a sensor unit 530 , a control unit 540 , an external reference clock 550 and a power supply unit 560 , which are also components of a mechanical timepiece body 500 . The sensor unit 530 is a duplicated unit consisting of a main sensor 531 and an auxiliary sensor 531 and is built into the mechanical timepiece body 500 . It detects the vibration of the balance wheel of the oscillator 510 and transmits a detection signal to the control unit 540 . The control unit 540 is electrically connected to the other components to receive detection signals, send control signals, and control the supply of power. The external reference clock 550 is an external transmitter that incorporates an oscillator that vibrates separately from the balance that constitutes the mechanical timepiece, and transmits the reference clock signal, which is the oscillation signal, to the control unit 540. The power supply unit 560 is made up of a button battery (1.55V), a DC-DC booster that boosts the voltage of the button battery to 10V, and a current monitor that monitors the average current I_avg.

[0038] Actuator 520 is attached to vibrator 510. Reference numeral 511 denotes the vibrator's hole, and 512 denotes the vibrator's main vibration axis. Actuator 520, which consists of two electronic actuators, is fixed to hole 511. Actuator 520 is arranged in a direction (referred to as the X-axis) perpendicular to the vibrator's main vibration axis (referred to as the Z-axis), and is composed of a pair of electronic actuators each having position vectors r1 and r2 as viewed from the main vibration axis. These actuators can apply forces F1 and F2 in opposing directions along the X-axis, and a rotational torque component about the main vibration axis is generated by the cross product of each force vector and the position vector. This minute vibration energy in the orthogonal direction is transferred to the main vibration along the main vibration axis via a mechanical cross-axis coupling.

[0039] (Duplicated sensor unit) The sensor unit 530 is composed of different types of main and auxiliary sensors. Here, an infrared laser is used as the main sensor to detect the position and speed of the oscillator balance. An optical sensor for detecting balance markings is used as an auxiliary sensor, and it detects the position and speed of the oscillator balance using a method different from that of the main sensor. This combination, which uses both sensors optically, is not affected by magnetic fields and meets recent requirements for magnetic resistance. Furthermore, by combining the highly accurate position detection by laser with the reliable periodic detection by marking, extremely high detection reliability can be achieved.

[0040] Here, a combination of an infrared laser and an optical sensor for detecting temp markings is used as the combination of sensors that make up the sensor unit, but the combination of sensors that can be used in the present invention is not limited to this. The sensor is selected taking into consideration the structure of the movement, the required detection accuracy, power consumption, reliability requirements, and magnetic resistance requirements, etc. In particular, given the increasing demand for magnetic resistance in recent years, it is desirable to give priority to optical sensors. On the other hand, it is possible to use a sensor other than an optical sensor on one side, such as a combination of an optical position sensor and a three-axis acceleration sensor.

[0041] (Modification of sensor combination) A modified example will be described in which an optical position sensor is used as the main sensor and a three-axis acceleration sensor is used as the auxiliary sensor. In addition to the reliability evaluation function described later, an acceleration sensor can be used to detect external impacts, making it possible to treat loss of synchronization due to impacts as temporary. The optical main sensor ensures magnetic resistance, while also providing the secondary effect of improving resistance to external disturbances during everyday use.

[0042] (control unit) The operation of each functional component shown here is realized by executing a control program such as pre-installed firmware on a specified processor or dedicated hardware circuit, and by cooperating with various devices that constitute the device. The control unit 540 compares the phase and cumulative frequency of the oscillator with a reference clock from an external reference source 550 to achieve phase synchronization.

[0043] A microcontroller unit (hereinafter referred to as MCU) is employed for the control unit 540. The MCU refers to an external reference signal, monitors the state of the vibrator in real time, and executes control processing based on PI (Proportional-Integral) control. As in Example 1, the MCU calculates the phase difference ΔΦ between the current phase of the oscillator and the reference signal in real time, derives a correction amount proportional to this ΔΦ, and instantly adjusts the pulse injection timing (P control). In addition, the cumulative frequency difference ΔN between the oscillator and the reference signal is calculated, and the control parameters such as the total amount and width of pulse injection are adjusted by integrally reflecting the correction amount based on ΔN so that this ΔN becomes zero (I control). This allows the MCU to dynamically control the injection amount and injection timing of the pulse external force output to the pulse generator, and synchronize the frequency and phase of the oscillator with an external reference.

[0044] FIG. 6 is a functional block diagram showing the functional configuration of the control unit. The control unit 540 is generally composed of a control unit 601 and a pulse generator 611 that outputs a pulse external force control command in accordance with a pulse control profile and a drive trigger generated by the control unit. The control unit 601 is composed of a sensor signal processing unit 602, a real vibration counter 603, a phantom count generation unit 604, a reference vibration counter 605, a step-out counter 606, a recording unit 607 that records log information of past vibration states, etc., a measurement reliability evaluation unit 608, a comparison unit 609, and a control policy determination unit 610.

[0045] The sensor signal processing unit 602 detects the vibration state of the balance based on the signal obtained from the vibration sensor, generates a detection signal corresponding to the periodic displacement of the vibration, and sends it to the real vibration counter 603. The vibration state includes the frequency and amplitude of the vibration. If an abnormal vibration is detected in terms of period or amplitude, the step-out detection signal is generated and sent to the step-out counter 606 . If vibration is not detected, the phantom count generating unit 604 is notified of non-detection as phantom count processing.

[0046] Every time a detection signal is received, the real vibration counter 603 increments the cumulative real vibration count up to that point, and sequentially records the number of vibrations since the start of measurement.

[0047] When the phantom count generator 604 cannot receive a detection signal from the sensor signal processor 602 within a predetermined time or is notified of non-detection, it references log information of past vibration states stored in the recorder 607 and generates a phantom count signal that simulates a periodic displacement similar to that of real vibration based on the vibration period and amplitude recorded in the log. The generated phantom count signal is sent to the real vibration counter 603 and processed in the same way as a normal detection signal.

[0048] Each time the reference vibration counter 605 receives a reference clock signal from the reference clock, it increments the cumulative number of reference vibrations up to that point, and sequentially records the number of vibrations since the start of measurement.

[0049] Each time an out-of-step detection signal is received, the out-of-step counter 606 increments the cumulative number of out-of-steps up to that point, and sequentially records the number of out-of-steps since the start of measurement.

[0050] The recording unit 607 records log information on the vibration state of the transducer, log information on the generation of the phantom count signal, and log information on the step-out count of the transducer.

[0051] The measurement reliability evaluation unit 608 generates reliability information in three stages: "high reliability," "medium reliability," and "abnormal" as follows. If sensor signals are detected from both sensors simultaneously, a "high confidence" credibility information is generated as a highly reliable detection. If a sensor signal is detected from only one of the sensors, credibility information of "medium reliability" is generated as a medium reliability detection, and processing to confirm the state of the other sensor is performed. If neither sensor signal is detected by either sensor, or if the ratio of the cumulative number of out-of-steps to the cumulative real frequency exceeds a predetermined value, the system generates "abnormal" credibility information as an abnormality. At this time, a phantom count generation request is sent to the phantom count generation unit as part of the phantom count processing.

[0052] The evaluation shown here is an example of an evaluation that can be adopted in the present invention, and can be appropriately changed from the viewpoint of highly accurate control. To achieve more precise control, a method can be adopted that comprehensively assesses reliability based on indicators such as the occurrence rate of out-of-step beats, variations in vibration period, stability of the most recent vibration pattern, frequency of use of phantom counting, or degree of detection agreement between sensors.

[0053] The comparison unit 609 compares the current phase of the oscillator with the phase of the reference clock signal to calculate the phase difference ΔΦ, and also compares the accumulated real frequency stored in the real frequency counter with the accumulated reference frequency stored in the reference frequency counter to calculate the accumulated frequency difference ΔN.

[0054] The control policy determination unit 610 performs proportional control based on the phase difference ΔΦ detected in real time, and generates the pulse control profile and basic parameters of the drive trigger using a correction amount proportional to the phase difference (P control). Furthermore, integral control is performed based on the cumulative frequency difference ΔN, and a correction amount corresponding to the cumulative error is added to the basic parameters, thereby correcting the long-term frequency deviation (I control). The control parameters thus obtained are adjusted as follows, with reference to the credibility information at that time. When "high reliability" confidence information is generated, the control gain is set high, the response speed is fast, and the correction amount is adjusted to the control parameters faithfully based on the measured value, and the phantom count is set to the minimum. When "medium reliability" reliability information is generated, the control gain is set to medium, the response speed is set to standard speed, and the control parameters are adjusted to smooth the correction amount using a moving average of the measurement value, etc., and phantom counts are set to be used as necessary. When "abnormal" confidence information is generated, the control parameters are adjusted to lower the control gain, slow the response speed, and minimize or stop the correction amount, and the phantom count is actively used to suppress cumulative errors.

[0055] The parameter adjustment shown here is one example of parameter adjustment that can be adopted in the present invention, and can be changed as appropriate from the viewpoint of highly accurate control.

[0056] The control parameters after parameter adjustment are sent to the pulse generator 611 and are used to inject an external force pulse by the actuator.

[0057] The pulse generator 611 transmits a pulse external force control command to the actuator in accordance with the control parameters generated by the control policy determination unit 610 .

[0058] (Control Flow) FIG. 7 is a flowchart showing the control flow of the control unit. In step B1, the vibration state of the vibrator is detected from the sensor signal by the sensor signal processing unit. In step B2, the control unit obtains the cumulative real vibration number from the cumulative real vibration counter. In step B3, the measurement reliability evaluation unit generates reliability information in three levels: "high reliability," "medium reliability," and "abnormal."

[0059] In step B4, the control unit compares the current phase of the oscillator with the phase of the reference clock signal to calculate the phase difference ΔΦ, and also compares the accumulated real frequency stored in the real vibration counter with the accumulated reference frequency stored in the reference vibration counter to calculate the accumulated frequency difference ΔN.

[0060] In step B5, the control unit performs proportional control based on the phase difference ΔΦ detected in real time, and generates the pulse control profile and basic parameters of the drive trigger using a correction amount proportional to the phase difference (P control). Furthermore, integral control is performed based on the cumulative frequency difference ΔN, and a correction amount corresponding to the cumulative error is added to the basic parameters to correct the long-term frequency deviation (I control).The control parameters before reliability adjustment obtained in this way are further adjusted with reference to the reliability information at that time, and are output to the pulse generator as control parameters for generating a pulse external force command.

[0061] In step B6, the control unit generates a pulse external force command from the control parameters obtained in step B4 and outputs it to the pulse generator. In step B7, the pulse generator drives the actuator and injects an external force pulse into the main vibration axis of the vibrator.

[0062] In step B8, the operations from B1 are repeated. [Industrial Applicability]

[0063] The present invention is applicable to a wide range of mechanical timepieces depending on the implementation level. As an example of application of the basic configuration, it can be used to improve the accuracy of mid-range mechanical watches and as a cost-effective solution for improving accuracy. Examples of applications in advanced configurations include ultra-high precision in luxury mechanical watches, fine tuning of watches using new materials such as silicon balance springs, high-precision watches with accuracy exceeding chronometer standards, and use in environments requiring high magnetic resistance (around medical equipment, industrial sites, etc.). In either configuration, it is possible to improve accuracy using electronic technology without making major changes to the traditional mechanisms of mechanical timepieces, making it a valuable technological innovation in the timepiece industry. [Explanation of symbols]

[0064] 100 Mechanical watch body 110 Transducer 120 Actuator 130 Sensor Unit 140 Control Unit 150 External Reference Clock 160 Power supply section

Claims

1. A method for controlling the rate of a mechanical timepiece, comprising: a) detecting the vibrations of the balance with a sensor and recording the cumulative number of vibrations from the start of measurement; b) comparing the cumulative number of clock signals obtained from an internal reference oscillator with the cumulative number of oscillations; c) injecting energy into the balance by means of an actuator according to a predetermined control scheme; Including, A rate control method characterized by further comprising a step of adding a virtual number of vibrations estimated from a reference oscillator and past vibration history to a cumulative number of vibrations for a period during which vibration detection by the sensor is not performed.

2. 2. The rate control method according to claim 1, further comprising the step of determining a control method for rate correction based on the result of said comparison.

3. 2. The rate control method according to claim 1, further comprising the step of recording the frequency of vibrations that deviate from the standard, and evaluating the reliability of the measurement based on the frequency of vibrations that deviate from the standard.

4. 4. The rate control method according to claim 3, further comprising changing a control parameter in accordance with the reliability of the measurement.

5. 2. The rate control method according to claim 1, wherein the vibration detection by the sensor is performed by a plurality of sensors based on different detection principles, and the detection results of the sensors are collated.

6. A rate control device for a mechanical timepiece, a) a sensor for detecting the oscillations of the balance; b) a reference oscillator that generates a reference clock signal; c) counting means for counting the cumulative number of vibrations based on the signal from the sensor; d) a control means for comparing the cumulative frequency with a reference clock cumulative frequency to determine a control method; e) an actuator for injecting energy into the balance in accordance with said control method; A rate control device comprising:

7. 7. The rate control device according to claim 6, further comprising: evaluation means for counting the number of vibrations that deviate from the standard and evaluating the reliability of measurement based on the number of vibrations that deviate from the standard.

8. A mechanical timepiece equipped with the rate control device according to claim 6.

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