EP2652563B1 - Method and device for obtaining a continuous movement of a display means - Google Patents

Description

The present invention relates to the field of display devices, and in particular electromechanical timepieces provided with an analog-type display.

In mechanical timepieces, in particular wristwatches with needles, time-setting devices actuated by a crown kinematically connected to the minute-gear train of the watch in its axial position corresponding to the setting mode are known. time, with determined gear train ratios to move the minute hand simply and quickly without having to rotate the crown either too long or often.

In electronic timepieces with digital display, in particular with liquid crystals, it is known to be able to accelerate the scrolling speed of digital symbols as a function of prolonged or repeated activation of a sensor when one is in a specific setting mode. For example, a prolonged pressure on a push button makes it possible to accelerate the scrolling up to a maximum speed for the display value to be corrected. Adjustment is then carried out sequentially for each display parameter.

It is also known to correct a digital display by using a crown provided with sensors as an actuating element, and an electronic control device to perform a correction at a speed proportional to that of rotation of the crown, such as for example the electronic circuit described in the patent GB 2019049 . In this case, the correction speeds are constant between different levels corresponding to rotational speeds of the crown, but can however change abruptly during each increment. Otherwise, no correction takes place between two successive movements of the crown, and no mechanism is provided to slow down the scrolling of the counter used for the correction. Thus a fine adjustment implies a repetition of low amplitude actuations by the user, in order to generate the lowest possible correction speed. This proves on the one hand inconvenient, and on the other hand does not make it possible to overcome a jerky movement of the needles.

The Swiss patent CH 641630 describes an electronic device for scrolling symbols at a variable speed in response to the activation of a sensor (movement of a finger on a touch sensor, pressure on a push button). The number of activations of the sensors and the duration of these activations have the effect of incrementing or decrementing the values contained in a register, which in turn determine a proportional scrolling speed. Decrementing the register values after a prolonged inactivation of the sensors makes it possible to gradually decrease the scrolling speed; however, this slowing down of the scrolling speed still lacks fluidity since the relative variations of the scrolling speed are all the greater the closer the register values are to zero. This solution has the advantage of using sensors without mechanical parts; the disadvantage is that the use is less intuitive than a traditional crown. Moreover, this solution relates only to digital displays and does not apply to watches comprising analog display members.

The document CH 702 862 A1 describes a digital display timepiece comprising, in the embodiment of the figure 4 , a physical crown. A user's action on the crown is detected and the timepiece's processor uses this information, in combination with other measured/simulated force/torque values, to perform a simulation of the actual position of the components of a simulated mechanical watch movement. Indeed, we see on the figure 4 of this document that a simulation at all times of the position of the (virtual) components of a mechanical movement is displayed on the digital display device of the timepiece. To obtain an accurate and realistic simulation, virtual masses, inertias and elasticities are assigned to the displayed virtual components.

It is also known, in electromechanical watches in particular, to display the direction of magnetic North using hands. The movement of the North indicator hand is however often jerky and therefore not very intuitive for the user of the watch.

An object of the present invention is therefore to propose a solution free from the aforementioned drawbacks of the prior art.

In particular, an object of the present invention is to propose a more fluid and more intuitive display device for the user.

These objects are achieved by means of a method for determining a variable and continuous speed movement of analog display means of an electromechanical timepiece according to claim 1.

These objects are also achieved thanks to a timepiece according to claim 6.

Preferred embodiments of the invention are defined in the dependent claims.

An advantage of the proposed solution is to make the adjustment operation on the one hand more efficient, and on the other hand visually more intuitive thanks to the emulation of a Newtonian movement for the display means, i.e. that is, whose speed is continuous with acceleration and deceleration proportional to an applied torque or force. It is thus possible to adjust the scrolling speed to the magnitude of the correction, by first performing a coarse adjustment then a finer adjustment when approaching the desired value, with a speed that is always continuous.

An additional advantage of the proposed solution is that it does not require any particular sensor resolution to increment the display values. The fluidity of the adjustment is ensured in particular by the fact that it is not a correction speed which is deduced from the movements of a control member, or detected by a sensor, but the acceleration of the display means. This therefore makes it possible to generate a continuous speed of these display means, in accordance with the movement of a mechanical member according to Newtonian laws of physics. This speed presents only small variations between different periods of actuation of the control member, and the proposed solution therefore does not undergo any threshold effect at the level of the sensor resulting in jerks for the movements of the control members. 'display.

Another advantage of the proposed solution is also to minimize the manipulations necessary for adjustment, only a few sporadic activations of the control member being necessary to adjust the position of the display elements. Furthermore the control of Adjustment operations are improved thanks to the possibility of acting not only to accelerate the speed of correction but also to decelerate this same speed.

An additional advantage of the proposed solution is to allow simultaneous adjustment of several display parameters, unlike the usual sequential adjustments for electronic watches. The time saved by the invention for the correction thanks to a continuous movement of the display means between the periods of actuation of the activation means gives the possibility of moving, for example, the hour and minute hands at the same time. , following the intuitive approach of a classic mechanical watch, without large-scale correction taking too long in the eyes of the user.

• la figure 1A illustre une vue schématique du dispositif de commande selon un mode de réalisation préférentiel de l'invention pour le réglage de paramètres horaires;
• la figure 1B montre les différents paramètres utilisés et les différentes étapes de calcul effectuées par divers éléments du dispositif de commande selon le mode de réalisation préférentiel illustré à la figure 1A;
• la figure 2A illustre une structure de capteur selon un mode de réalisation préférentiel de l'invention;
• la figure 2B montre le fonctionnement du capteur selon le mode de réalisation préférentiel illustré par la figure 2A;
• la figure 3 montre un diagramme d'état pour les différentes séquences d'opérations de réglage selon un mode de réalisation préférentiel de l'invention.
• la figure 4A illustre une vue schématique du dispositif de commande selon un mode de réalisation préférentiel de l'invention pour une boussole électronique;
• la figure 4B montre les différents paramètres utilisés et les différentes étapes de calcul effectuées par divers éléments du dispositif de commande selon le mode de réalisation préférentiel illustré à la figure 4A;

Other features and advantages will emerge more clearly from the detailed description of various embodiments and the accompanying drawings, in which:

• the Figure 1A illustrates a schematic view of the control device according to a preferred embodiment of the invention for setting time parameters;
• the figure 1B shows the different parameters used and the different calculation steps performed by various elements of the control device according to the preferred embodiment illustrated in Figure 1A ;
• the figure 2A illustrates a sensor structure according to a preferred embodiment of the invention;
• the figure 2B shows the operation of the sensor according to the preferred embodiment illustrated by the figure 2A ;
• the picture 3 shows a state diagram for the different sequences of adjustment operations according to a preferred embodiment of the invention.
• the figure 4A illustrates a schematic view of the control device according to a preferred embodiment of the invention for an electronic compass;
• the figure 4B shows the different parameters used and the different calculation steps performed by various elements of the control device according to the preferred embodiment illustrated in figure 4A ;

A preferred embodiment of the control device of the invention is intended for timepieces and is illustrated in the figures 1A and 1B , which respectively show the logical structure of the control device 3 as well as the different parameters used and the different calculation steps carried out by various elements of the control device 3 to transform the movement of the activation means 1 into a non-proportional movement of the means display, unlike a traditional mechanical cog. The Figure 1A shows the preferential structure of the activation means 1, in the form of a crown 11, the actuation of which can be performed in two opposite directions of rotation S1 and S2, as well as that of the display means 2, in the form an hour hand 22 and a minute hand 21. One could however imagine applying the control device 3 according to the invention to other types of rotating mechanical display members 2, such as for example rings or drums. The invention therefore makes it possible to transform a first angular speed 111, corresponding to that of the drive of the crown 11 in a given direction of rotation, for example S1, into another angular speed 211 of the minute hand 21. The two angular speeds 111 and 211 are not proportional, since the minute hand 211 is progressively accelerated following the actuation of the crown 11 in the direction S1 in accordance with a Newtonian equation of movement 700 described later, which allows elsewhere to give a continuous character to the movement of the needles.

The control device 3 according to the preferred variant of the invention illustrated in Figure 1A comprises an electronic circuit 31 preferably in the form of an integrated circuit comprising a processing unit 5, comprising for example a microcontroller, and a motor control circuit 6. The microcontroller transforms digital input parameters, provided by a counter module 44 at the output of a first sensor 4 of movements of the activation means 1, i.e. for example the rotation of the crown 11, into instructions for the motor control circuit 6, such as for example a number of not motors. The counter module 44 makes it possible to transform the electrical signals produced by the first sensor 4 into discrete digital values, and therefore manipulable by a software processing unit 5 such as a microcontroller. However, the latter is not described in detail because it is known to those skilled in the art. According to the preferred variant illustrated, the control circuit 6 controls two separate motors, a first motor 61 being dedicated to controlling the movements of the minute hand 21, and a second motor 62 being dedicated to controlling the hour hand 22 The control device 3 thus simultaneously actuates a plurality of motors 61, 62 each dedicated to distinct mechanical display means. The dissociation of the motors makes it possible to quickly change the display mode, by indicating, for example, the time of an alarm, or the direction of the earth's magnetic field.

• l'étape 4001 consiste en la détermination d'une fréquence d'impulsions 401, utilisée en sortie du module compteur 44 par le microcontrôleur de l'unité de traitement 5 pour calculer le nombre de pas moteurs et en déduire la fréquence de pas moteurs 611, 622. Une structure préférentielle pour le premier capteur 4 utilisé pour réaliser cette étape 4001 est détaillée plus loin à l'aide des illustrations des figures 2A et 2B;
• lors de l'étape 5000, un coefficient de proportionnalité 701 est multiplié à la fréquence d'impulsions 401 pour déterminer une valeur de couple 401', fictif, et qui est censé être appliqué, selon la modélisation choisie dans le cadre de l'invention, à l'aiguille des minutes 21 autour de son axe de rotation.
• l'étape 5001 est l'étape de calcul principale réalisée par le microcontrôleur. Elle vise à déterminer la fréquence de pas moteurs 611 du premier moteur 61 en fonction de la fréquence d'impulsions 401, afin d'en déduire la vitesse angulaire 211 effective de l'aiguille des minutes. Pour ce faire, le microcontrôleur résout une première équation newtonienne 700, modélisant ici le mouvement de l'aiguille des minutes 21 comme celui d'un système tournant selon le principe fondamental de la dynamique, qui stipule que l'accélération angulaire d'un corps en rotation est proportionnelle à la somme des couples mécaniques qui lui sont appliqués. Avec les paramètres de simulation choisis dans le cadre du mode de réalisation préférentiel de l'invention, la première équation newtonienne se lit: $$704*703\prime =401\prime -703",$$
  
  où dans la partie gauche de l'équation le coefficient 704 correspond au moment d'inertie du système tournant simulé (usuellement représenté par la lettre J dans des équations physiques) et la référence 703' correspond à l'accélération des moyens d'affichage utilisée dans le cadre de l'invention, comme par exemple ici l'aiguille des minutes 21 autour de son axe de rotation. Afin de conférer un maximum d'inertie au mouvement de l'aiguille des minutes 21, c'est-à-dire pour qu'elle continue de tourner le plus longtemps possible entre les activations de l'organe de commande, on pourra noter que le coefficient 704 du moment d'inertie du système tournant simulé est choisi de préférence beaucoup plus grand que le moment d'inertie réel de l'aiguille des minutes 21, ce qui lui donne le comportement d'un système plus massif, comme si elle était par exemple solidaire en rotation d'un disque en métal. Dans la partie droite de la première équation newtonienne 700 ci-dessus, la valeur 401' correspond à une valeur de couple mécanique fictive appliquée au système tournant qui est simulé pour l'aiguille des minutes 21. Le couple fictif 401', qui dépend de la fréquence d'impulsions 401, est différent de zéro lors de la rotation de la couronne 11. Un autre couple fictif 703", proportionnel à la vitesse angulaire 703 simulée des moyens d'affichage, en l'occurrence celle de l'aiguille des minutes 21, modélise un frottement fluide qui ralentit progressivement le mouvement de l'aiguille des minutes 21. Ce couple mécanique est le seul appliqué lorsque la couronne 11 n'est plus activée. Similairement à la valeur de couple fictif 401', la valeur de couple fictif 703" est obtenue en multipliant la vitesse angulaire simulée 703 par un coefficient de proportionnalité 702, appelé coefficient de frottement fluide. Cette modélisation de frottement fluide fait prendre dans ce cas à la première équation newtonienne 700 la forme d'une équation différentielle pour la vitesse angulaire simulée 703 de l'aiguille 21, qui est résolue par le microcontrôleur. Selon le mode de réalisation préférentiel décrit, la résolution de cette équation newtonienne du mouvement 700, permet ainsi d'émuler un mouvement d'aiguilles fluide et continu puisque la vitesse angulaire de cette dernière est déterminée comme s'il s'agissait de celle d'un système tournant soumis à un couple mécanique lorsque la couronne est actionnée, et un couple de ralentissement fluide. Selon le mode de réalisation préférentiel décrit ici, le paramètre d'entrée choisi pour cette équation est un couple fictif 401' proportionnel à la vitesse de rotation de la couronne 11, et comme résultat en sortie une vitesse de rotation 703 simulée de l'aiguille des minutes 21.

The microcontroller uses, to perform its calculations, various parameters saved in a memory unit 7, in order to be able to determine a number of motor steps, or even a frequency of motor steps 611, 622 when the latter are related to a time unit such as the second or minute. These frequencies of motor steps 611, 622 correspond respectively to the activation frequencies of the first motor 61 and of the second motor 62 according to the first Newtonian equation of movement 700, described below. The figure 1B illustrates the different stages of velocity transformation angle 111 of rotation of crown 11 in a number of motor steps, as well as the calculation parameters:

• step 4001 consists of determining a pulse frequency 401, used at the output of counter module 44 by the microcontroller of processing unit 5 to calculate the number of motor steps and deduce therefrom the frequency of motor steps 611 , 622. A preferential structure for the first sensor 4 used to carry out this step 4001 is detailed below using the illustrations of the figures 2A and 2B ;
• during step 5000, a proportionality coefficient 701 is multiplied at the pulse frequency 401 to determine a torque value 401', fictitious, and which is supposed to be applied, according to the modeling chosen within the framework of the invention , to the minute hand 21 around its axis of rotation.
• step 5001 is the main calculation step performed by the microcontroller. It aims to determine the frequency of motor steps 611 of the first motor 61 as a function of the pulse frequency 401, in order to deduce therefrom the effective angular speed 211 of the minute hand. To do this, the microcontroller solves a first 700 Newtonian equation, here modeling the motion of the 21 minute hand as that of a rotating system according to the fundamental principle of dynamics, which states that the angular acceleration of a body in rotation is proportional to the sum of the mechanical torques applied to it. With the simulation parameters chosen within the framework of the preferred embodiment of the invention, the first Newtonian equation reads: $$704*703\prime =401\prime -703",$$
  
  where in the left part of the equation the coefficient 704 corresponds to the moment of inertia of the simulated rotating system (usually represented by the letter J in physical equations) and the reference 703' corresponds to the acceleration of the display means used in the context of the invention, such as here for example the minute hand 21 around its axis of rotation. In order to confer maximum inertia on the movement of the minute hand 21, that is to say so that it continues to rotate as long as possible between activations of the control member, it may be noted that the coefficient 704 of the moment of inertia of the simulated rotating system is preferably chosen much larger than the real moment of inertia of the minute hand 21, which gives it the behavior of a more massive system, as if it was for example integral in rotation with a metal disc. In the right part of the first Newtonian equation 700 above, the value 401' corresponds to a fictitious mechanical torque value applied to the rotating system which is simulated for the minute hand 21. The fictitious torque 401', which depends on the pulse frequency 401, is different from zero during the rotation of the crown 11. Another fictitious torque 703 ", proportional to the simulated angular speed 703 of the display means, in this case that of the minutes 21, models a fluid friction which progressively slows down the movement of the minutes hand 21. This mechanical torque is the only one applied when the crown 11 is no longer activated. fictitious torque 703" is obtained by multiplying the simulated angular velocity 703 by a proportionality coefficient 702, called fluid friction coefficient. This modeling of fluid friction in this case causes the first Newtonian equation 700 to take the form of a differential equation for the simulated angular velocity 703 of the needle 21, which is solved by the microcontroller. According to the preferred embodiment described, the resolution of this Newtonian equation of movement 700 thus makes it possible to emulate a fluid and continuous movement of hands since the angular speed of the latter is determined as if it were that of a rotating system subjected to a mechanical torque when the crown is actuated, and a fluid deceleration torque. According to the preferred embodiment described here, the input parameter chosen for this equation is a fictitious couple 401' proportional to the speed of rotation of crown 11, and as output result a simulated speed of rotation 703 of minute hand 21.

• l'étape 5002 déduit la valeur de fréquence 622 du deuxième moteur 622 en fonction de la valeur de fréquence du premier moteur 611 trouvée en sortie de l'étape 5001. En effet le rapport des vitesses de rotation entre l'aiguille des minutes 21 et celle des heures 22 est de 12, dans le cadre d'un affichage analogique standard selon lequel une révolution complète de l'aiguille des minutes 21 correspond à l'avancement d'une heure de celle de l'aiguille des heures 22, soit d'un douzième de cadran pour une graduation des heures de 1 à 12. Il est ainsi relativement aisé de déduire la valeur de fréquence 622 du deuxième moteur 62 sans devoir effectuer de calcul intrinsèque, ni d'opération de division, mais simplement en implémentant au niveau du circuit de commande des moteurs 6 un ordre d'implémentation d'un pas du 2^e moteur 62 après chaque 12^e pas du premier moteur 61. Les exigences en termes de calcul sont ainsi minimisées tout en procurant un effet visuel intuitif de mouvement coordonné de plusieurs organes d'affichage, à savoir l'aiguille des minutes 21 et celle des heures 22, lors de leur réglage. La subordination de cette étape additionnelle de calcul 5002 à l'étape de calcul précédente 5001 selon le mode de réalisation préférentiel décrit permet par ailleurs de coordonner simplement le mouvement des deux aiguilles 21, 22.

The simulated rotational speed 703 then makes it possible to deduce proportionally the number of motor steps per second, that is to say the frequency of motor steps 611. The effective angular speed of the minute hand 211 is reciprocally proportional to the frequency motor steps 611 thus established. According to a preferred variant of the invention, each motor step causes a movement of the hand 21 of an angular sector corresponding to an indication of duration less than one minute. In order to make the scrolling of the hands as fluid as possible, the angular value of angular incrementation of each step is chosen, preferably equal to 2 degrees. In other words, each motor step causes the minute hand 21 to rotate by an angular value corresponding to one third of that corresponding to one minute. A finer resolution would also be possible but would require increased use of the motor 61 which would have to increment more steps and would in this case consume all the more energy.

• step 5002 deduces the frequency value 622 of the second motor 622 as a function of the frequency value of the first motor 611 found at the output of step 5001. Indeed the ratio of rotational speeds between the minute hand 21 and that of the hours 22 is 12, in the context of a standard analog display according to which a complete revolution of the minute hand 21 corresponds to the advancement of one hour of that of the hour hand 22, i.e. d twelfth of a dial for a graduation of hours from 1 to 12. It is thus relatively easy to deduce the frequency value 622 of the second motor 62 without having to perform any intrinsic calculation, nor any division operation, but simply by implementing at level of the motor control circuit 6 an order of implementation of a step of the 2 ^nd motor 62 after each 12 ^th step of the first motor 61. The requirements in terms of calculation are thus minimized while providing an intuitive visual effect of movement coordinate of several display organs, namely the minute hand 21 and the hour hand 22, during their adjustment. The subordination of this additional calculation step 5002 to the previous calculation step 5001 according to the preferred embodiment described also makes it possible to simply coordinate the movement of the two hands 21, 22.

According to this preferred embodiment described above, the activation means 1 are preferably mechanical; however, they can also take the form, for example, of a capacitive sensor, such as a touch screen.

The actuation of the activation means 1 makes it possible to impart a variable and continuous movement to the display means 2, and in particular the minute hand 21, thanks to the calculation of an acceleration 703' in proportion to a torque value 401 'determined at the output of the first sensor 4, in proportion to the values of the register of the counter module 44, which makes it possible to characterize the movement of the activation means 1, preferably a crown 11, by digital values, namely a number of pulses . The step of determining a pulse frequency 4001 is a digitization process necessary to provide an input parameter that can be manipulated by the electronic circuit 31, which can then simulate the movement of the mechanical display means as if it were determined by the application of a torque 401' proportional to the frequency of pulses 401. The actual movement of the hands is considered Newtonian because it corresponds to that of a rotating solid subject to the fundamental relationship of the dynamics, indicating that the acceleration of a rotating body is proportional to the sum of the torques applied to it. In the context of the invention, the fundamental dynamic equation could also be applied to linear, and not rotary, display means 2, in which case the acceleration would be proportional to the sum of the forces applied to the system. The movement of the 21 minute hand is determined by solving Newton's first equation of motion 700 which models this fundamental equation of solid dynamics using a first coefficient 701 determining the torque 401' applied to the system from the pulse frequency 401, and as well as, according to a preferred embodiment, a second coefficient 702 determining a so-called fluid friction torque because causing a deceleration of the speed of rotation of the hands proportionally to this same speed. The actual movement of the hands is also considered inertial because it corresponds to that of a solid in rotation which is no longer subject, as soon as the crown 11 is no longer activated, to a so-called fluid friction torque, proportional to its rotational speed itself, causing them to gradually slow down. According to the preferred embodiment described, this fluid friction torque 703" is however fictitious, and simulated by the microcontroller 5 within the framework of the Newtonian equation 700 above; it is moreover not applied directly to the minute hand 21, but at the simulated speed of minute hand 703 also used to solve Newtonian equation 700 above.

The method for determining the speed of the display means 2 according to the invention therefore solves a Newtonian equation of motion by using torque and/or force values as input parameters for the resolution of this equation. These parameters are themselves determined in relation to a physical quantity, here the angular speed 111 of the crown 11, which is transformed via the first sensor 4 and the counter module 44 into a pulse frequency 401. other physical quantities can however be used within the scope of the invention, such as for example a linear or angular speed, a magnetic field or a geometric angle. As will be seen later, the embodiment relating to an electronic compass, described in relation to the figures 4A and 4B , uses the geometric angle as an input parameter delivered to the processing unit to determine a torque to be applied to the needle 23 indicating magnetic north.

One of the specificities of the modeling proposed with respect to a "physical reality" is that the angular speed of the hands, and according to the preferred embodiment chosen the angular speed of the minute hand 211, is necessarily limited due to the constraints of the system in terms of processing capabilities. Indeed, the first and second motors 61, 62 can only implement a given maximum number of steps per second, and there is therefore always a maximum frequency of motor steps from which the Newtonian equation of motion 700 does not can no longer be applied, because the angular acceleration necessarily becomes zero. The maximum frequency of motor steps 611' of the first motor 61 controlling the minute hand 21 is preferably between 200 and 1000 Hz, which corresponds to the maximum speed of rotation of the minute hand 21 between approximately one and five revolutions per second when a complete turn of the dial corresponds to 180 motor steps. It may be noted that whatever the embodiment chosen for the invention involving the use of an electronic circuit 31, a maximum scrolling speed of the mechanical display means 2 must always be defined according to the processing capacities of the motor control circuit 6.

The figure 2A shows a preferred embodiment of the first sensor 4 according to the invention, which makes it possible to relatively simply determine a pulse frequency 401 used by the electronic circuit 31 in order to calculate the acceleration and/or deceleration values of the display means 1 by solving the first Newtonian equation 700 applied to this input parameter. The first sensor 4 is mounted on a rod 41, fixed in rotation to the crown 11, and which can be driven in rotation in two opposite directions S1 and S2. On the periphery of this rod 41 are mounted a plurality of electrical contactors 41a, 41b, 41c, 41d, preferably 4 in number, as illustrated in the figure 2A . The first sensor 4 also comprises two electrical contacts 42, 43 mounted on a fixed structure, a first contact 42 at the terminals of which is measured the value of a signal 412 of output and a second contact 43 across which the value of an output signal 413 is measured when a voltage is applied to the electrical contactors 41a, 41b, 41c, 41d.

The figure 2B shows, in the upper part (a), the first and second signals 412 and 413 obtained during a rotation of the crown 11 in the direction of rotation S1, corresponding to the clockwise direction. The first period 401a, corresponding to the duration during which each signal 412, 413 is positive, the second period 401b during which each signal 412, 413 is zero and the third total period 401c, corresponding to the sum of the first and second periods 401a, 401b are identical for each of the first and second output signals 412, 413, which are simply shifted in time by a value corresponding to the path of one of the electrical contacts 41a, 41b, 41c, ^41d from the first contact 42 to the 2nd contact 43 external. The diagram is reversed in the lower part (b) of the figure, where the crown 11 is turned in the anti-clockwise direction S2, and where the pulse of the first output signal 412 is formed before that of the second signal output 413. These signals 412, 413 are then transmitted to the counter module 44 to be converted into pulse frequency.

The use of the first contactor of the figure 2A to determine the frequency of pulses 401 applied to the first Newtonian equation 700 also has the advantage of not requiring any fine resolution of the first sensor 4 to guarantee the fluidity of the correction, since the speed determined by solving a Newtonian equation is always continues even if the acceleration is not. Thus a less fine resolution of the granularity of the torque values, proportional to the frequency of pulses 401, will not have the consequence of causing the display means 2 to advance jerkily, but simply of generating sharper accelerations following the detection of each additional pulse. One could therefore also use a sensor with three, two or even a single contactor and compensate for this reduction in the number of contactors by increasing, for example, the coefficients in parallel to obtain a given simulated torque value to be applied to the display means 2.

It is also possible, according to an alternative embodiment, to use one or more contactors associated with one or more push buttons (not shown) and to increment the pulse frequency 401 each time a first push button is pressed, and respectively decrement the pulse frequency 401 each time a second push button is pressed. According to this alternative embodiment, two sensors will therefore be used, each dedicated to increasing and respectively decreasing the frequency of pulses 401, which corresponds according to the modeling of the invention to applying a fictitious mechanical torque in one direction or in the opposite direction to respectively accelerate and decelerate the movement of the hands 21, 22.

The picture 3 shows a state diagram for different sequences of time adjustment operations using hands according to a preferred embodiment of the invention applied to a timepiece. Those skilled in the art will understand that it is however possible to adjust other types of parameters that are not necessarily temporal (that is to say any type of symbol) and that the hands could be replaced by other analog display devices.

Step 1001 corresponds to a first activation of crown 11, which makes it possible to generate the movement of minute hand 21. When the crown is actuated in a given direction of rotation, for example in direction S1, the first sensor 4 detects a “positive” number of pulses 401 corresponding to a positive angular speed 111 for crown 11 and simulates the application of a torque, applied to the needle in the same direction. Thus the rotation of the crown 11 in the clockwise direction S1 makes it possible to advance the minute hand 21 on the dial. Repeated rotation of the crown 11 in the same direction S1 makes it possible to maintain positive the frequency of pulses 401 during the successive sampling periods used by the counter module 44, and therefore to further accelerate the movement of the hand 21 according to the first Newtonian equation 700 or modified Newtonian 700', until obtaining a fluid and continuous movement for which it is no longer possible to visually observe the jump of the needle during each step. However, the movement of the minute hand 21 cannot exceed a maximum angular speed, which is observed when the maximum frequency of motor steps 611' is reached, the rotation of the crown 11 no longer has any effect however that this maximum speed is reached. According to a preferred embodiment, a maximum simulated angular speed 7031 is determined as a function of the maximum motor step frequency 611'. As soon as the algorithm solving the Newtonian equation reaches this upper speed limit, it saturates, that is to say stops increasing the simulated angular speed 703 even if the algorithm were to give a result of a value superior.

The diagram of the picture 3 illustrates the comparison step 5003 performed by the microcontroller 5 to determine whether the speed is saturating, in which case the simulated angular speed 703 is limited to the maximum value 7031 and the angular acceleration 703' is zero for the sampling period over which the calculation has been made. The feedback loop starting from the comparison step 5003 towards a positive acceleration value 703' indicates that no saturation takes place until the maximum simulated angular velocity 7031 has not been reached.

Although step 1001 has been described in the context of an activation of the crown 11 in the direction of rotation S1 of the hands of a watch to preferably advance the minute hand 21 in the same direction, it is possible also ensure that an activation of the crown 11 in the reverse direction S2 similarly rotates the minute 21 and hour 22 hands in the opposite direction, the number of pulses 401 being calculated identically for each period sampling but the information on the direction of rotation determined by the first sensor 4 makes it possible to choose the direction of rotation applied to the needles by the first and second motors 61, 62.

Moreover, the solution proposed here according to which the movement applied to the mechanical display means is the result of an acceleration which depends on the speed of the crown, is very robust in the face of a low resolution crown. Moreover, the movement remains fluid, even if the user advances the crown in jerks: if a user rotates the crown in successive strokes, the corrections continue between the strokes. This provides significant time savings in the case where the mechanical display means are not very efficient. Thus a simultaneous adjustment of the hour hand 22 and the minute hand 21 in accordance with a totally mechanical approach, according to which the minute hand performs a complete rotation for each time change, is made possible at a speed acceptable to the user even for a relatively slow system. Indeed, to maintain this very intuitive approach for the user, a correction of a few hours for electronic timepieces with an analog display requires the minute hand to make a large number of motor steps, the execution of which may be prove far too long for the user if the motors are inefficient. However, the significant time saving provided by the invention thanks to the continuous movement of the hands between the periods of activation of the crown 11 makes it possible to carry out these adjustments simultaneously, independently of the performance of the electronics and of the motors.

Whatever the direction of rotation S1 or S2 of the crown 11, the activation step 1001 consequently makes it possible to simultaneously adjust the hour hand 22 and the minute hand 21, which is particularly advantageous for watches electronics where each parameter is usually set sequentially for performance reasons.

La résolution de cette équation newtonienne 700 détermine la décélération de type inertielle de l'organe d'affichage, comme par exemple l'aiguille des minutes 21 dans le mode de réalisation décrit précédemment, car la décélération est uniquement proportionnelle à la vitesse angulaire simulée 703. Lors de cette décélération de type inertielle, le système se trouve dans la première phase de décélération B1 illustrée sur la figure 3.Step 1001' is a step subordinate to step 1001, or more generally any activation step, which it immediately follows. This is a step during which crown 11, or more generally control means 1, ceases to be activated. During this step, the modeling of the invention means that no more external torque is applied to the system as soon as the detected pulse frequency 401 is zero, which depends among other things on the sampling period chosen at the level of the counter module 44 to determine the pulse frequency 401. As soon as the value 401 cancels out, the angular acceleration 703' is determined by the modeled fluid friction alone, namely according to the first Newtonian equation 700: $$703\prime =-703"/704$$

The resolution of this Newtonian equation 700 determines the inertial type deceleration of the display member, such as for example the minute hand 21 in the embodiment described above, because the deceleration is only proportional to the simulated angular speed 703 During this inertial-type deceleration, the system is in the first deceleration phase B1 illustrated in figure picture 3 .

If on the other hand, after having turned the crown 11 for example in the direction S1, the crown 11 is turned in the opposite direction S2 during an additional actuation step 1002, the angular acceleration 703' is still negative, but the B2 deceleration, shown on the picture 3 , is more pronounced because the sign of the dummy torque 401' becomes negative, acting with the angular acceleration 703' to slow the system more quickly.

Actuation of the crown 11 in the opposite direction makes it possible to further refine the adjustment using the additional activation step 1002 when approaching a desired value while the angular speed is at this moment there relatively high, because the second phase of deceleration B2 which is generated is more pronounced than the first phase of deceleration B1 which occurs only during prolonged inactivation of the crown 11.

As can be seen on the picture 3 , the first activation step 1001 is therefore always followed by an acceleration phase A of the mechanical display means 2, and firstly the minute hand 21 for which the acceleration is the most perceptible. This acceleration phase A ends as soon as the motor control circuit 6 detects that a maximum frequency has been reached, in this case that of step 611′ of the first motor 61, in which case a phase follows. C during which the simulated angular speed 703 is limited to the maximum angular speed value 7031. During this phase C, the minute hand 21 is therefore constant, limited by the maximum step frequency 611' of the first motor 61: the algorithm saturates. Any additional activation of crown 11 in the same direction of rotation S1 therefore has no impact on the real angular speed 211 of the minute hand; however, such activations make it possible to maintain the actual angular velocity 211 at this constant level by preventing the angular acceleration value 703' from becoming negative after too prolonged inactivation, corresponding according to the preferred embodiment described to a period of sampling, and which can be calibrated for example to one second. Furthermore, the proportionality coefficients defining the moments applied to the system in the first Newtonian equation of motion 700, namely the coefficient 701 of proportionality with respect to the pulse frequency 401 and that of fluid friction 702 can preferably be chosen, together with the maximum value of motor steps 611' of the first motor 61, such that the angular acceleration value 703 is always positive as soon as at least one pulse 401 is detected per second, or respectively the value chosen for the lapse time above, so that the effective angular speed 211 always remains constant if the crown 11 is activated at least once per second as soon as the maximum angular speed 21 has been reached.

It is therefore understood on reading the foregoing that, whatever the activation means, preferably mechanical 1 and the mechanical display means 2 used in the context of the invention, the phase acceleration A of the display means 1 is followed most of the time by a phase C during which the scrolling speed of the display means 2 is constant as soon as the difference in the display value displayed when the adjustment is undertaken and the value to be achieved is important. If the control means are not activated for a determined period, the first deceleration phase B1 of the display means 2 takes place following this prolonged inactivation; otherwise a second more pronounced deceleration phase B2 can be actuated during an additional activation step 1002 of the control means in the opposite direction to that used during the initial activation step 1001. In the case of a crown 11 these are opposite directions of rotation S2 if S1 was the first direction of rotation, and S1 if S2 was the first direction of rotation. The use of a second activation step 1002 depends on the preferences of the user of the display device in terms of scrolling speed and the moment from which he wishes to carry out a finer adjustment of the display element(s). analog.

The control method and device according to the invention therefore allows increased control throughout the adjustment operations by being able to accelerate and/or decelerate the scrolling of the display element(s) at any time. Furthermore, the speed variations are much more gradual than according to the solutions of the prior art where the speeds are directly deduced from the values of the sensor. The determination of an acceleration instead of a speed from the magnitudes of a sensor makes it possible to fluidify the movement of the mechanical display elements. Although the preferred solution described transforms a physical quantity into a physical quantity of the same order, namely an angular speed - that of the crown 11 - into another angular speed - those of the minute and 22 hour hands 21 - it is however possible also consider replicating the control device 3 to any other type of display means 2. In the case of timepieces, preference may be given to the generation of a rotary movement of display means 2 which are the more frequently used for mechanical watches, regardless of the mode of activation used (rotation of a crown, pressing of a push button, scrolling of a finger on a touch screen, etc.); however, displacements of linear indicators are also possible, in which case the fundamental equation of motion will no longer relate a moment of inertia and an angular acceleration, but a force and a linear acceleration. Similarly, the slowing down of the inertial motion is in this case no longer caused by a torque modeling fluid friction, but by a frictional force.

The figures 4A and 4B respectively illustrate a schematic view of the control device 3 according to a preferred embodiment of the invention, as well as parameters and calculation steps used for the production of an electronic compass. Contrary to the embodiment described previously, the compass does not require any adjustment of the position of the north indicator hand 23 on the part of the user, this position being determined automatically by calculation. The activation means 1, serving only to activate an operating or display mode, have therefore not been shown.

On the figure 4A we distinguish, similarly to the Figure 1A , the electronic circuit 31 comprising the calculation unit 5, preferably constituted by a microprocessor or a microcontroller, the memory unit 7, and the motor control circuit 6. A new motor 63 is however introduced to control the movement of compass needle 23. The second sensor 4' differs from the first sensor 4 in that it measures another type of physical quantity, namely a magnetic field. It may for example be a magnetic sensor of the fluxgate type or any other suitable magnetic sensor. The so-called positioning circuit 45 determines the relative angle 451 between the direction of north determined by the second sensor 4' and the current position of the hand 23. This relative angle 451 is the input parameter delivered to the microprocessor to resolve the 700" Newtonian type equation of motion shown in figure 4B described below. It can be seen from reading the figure 4A that the first physical quantity, that is to say the magnetic field measured by the second sensor 4', has been transformed by a second physical quantity, namely the relative angle 451, by the positioning circuit 45, which therefore acts pre-processing circuitry to determine the torque and/or mechanical force values applied to the modeled system. This positioning circuit 45 is quite comparable to the counter module 44 of the embodiment of the figures 1A and 1B described previously, which also transforms a speed of rotation 111 into a frequency of pulses 401, and therefore also constitutes a pre-processing circuit.

• • lors de l'étape 5000', un coefficient de proportionnalité 705 est multiplié au sinus de l'angle relatif 451 pour déterminer une valeur de couple 451', fictive, laquelle est censée correspondre, selon la modélisation choisie dans le cadre de l'invention, à un couple appliqué à l'aiguille de la boussole 23 indicatrice du nord autour de son axe de rotation. Puisque l'on cherche à stabiliser l'aiguille 23 dans la direction du nord déterminée par le deuxième capteur magnétique 4' d'une manière la plus intuitive possible selon un mouvement correspondant à une réalité physique, les valeurs de couple 451' oscilleront ainsi entre des valeurs positives et négatives en fonction de l'angle relatif 451, matérialisant une force de rappel exercée sur l'aiguille 23 dans un sens ou dans l'autre.
  • l'étape 5004 vise à déterminer la fréquence de pas moteurs 633 du troisième moteur 63. Cette étape comprend une première sous-étape de calcul de l'accélération angulaire simulée des moyens d'affichage 703', en l'occurrence l'accélération angulaire de l'aiguille 23 de la boussole 21 selon le principe fondamental de la dynamique appliqué à la physique du solide, formalisé par la deuxième équation newtonienne 700' suivante: $$703\prime =\left(451\prime -703"\right)/704,$$
    
  le coefficient 704 correspondant au moment d'inertie simulé du système (usuellement représenté par la lettre J), qui modélise dans ce cas le moment d'inertie d'un système tournant associé à l'aiguille indicatrice du nord de la boussole 23 autour de son axe de rotation, 451' étant le couple fictif qui lui est appliqué en fonction du sinus de l'angle formé par l'aiguille 23 de la boussole 21 et la direction du Nord. Similairement à la première équation newtonienne 700 précédente pour déterminer le mouvement de l'aiguille des minutes 21, le coefficient 704 du système tournant simulé est ici encore choisi, dans le cadre de la deuxième équation newtonienne 700', de préférence beaucoup plus grand que le moment d'inertie réel de l'aiguille de la boussole 23, afin de conférer à cette aiguille le comportement d'un système plus massif. Selon le mode de réalisation préférentiel illustré, et similairement au mode de réalisation préférentiel décrit précédemment pour la correction d'indications horaires, un couple fictif 703" proportionnel à la vitesse angulaire simulée 703, pour déterminer cette fois-ci la vitesse angulaire 233 de l'aiguille de la boussole 23, a été introduit pour modéliser un frottement fluide ralentissant progressivement le mouvement de cette aiguille 23. Similairement à la valeur de couple 401', la valeur de couple 703" est obtenue en multipliant la vitesse angulaire 703 simulée par un coefficient de proportionnalité 702, appelé coefficient de frottement fluide. Selon une variante préférentielle de l'invention, chaque pas moteur provoque un mouvement de l'aiguille 23 de la boussole d'un secteur angulaire restreint, afin de fluidifier au maximum le mouvement de l'aiguille. Afin de rendre le défilement de cette aiguille de la boussole 23 le plus fluide possible, on choisit la valeur angulaire d'incrémentation de chaque pas de préférence inférieure ou égale à 1 degré. Autrement dit, chaque pas moteur du moteur 63 fait tourner l'aiguille 23 de la boussole d'une valeur angulaire correspondant à un sixième de celui correspondant à une minute, de telle sorte que les pas du moteur ne sont quasiment plus perceptibles à l'œil nu.

The figure 4B illustrates the different steps for determining the number of motor steps 633 of the motor 63 dedicated to the electronic compass as well as the calculation parameters:

• • during step 5000', a proportionality coefficient 705 is multiplied by the sine of the relative angle 451 to determine a torque value 451', fictitious, which is supposed to correspond, according to the modeling chosen within the framework of the invention , to a torque applied to the compass needle 23 indicating north around its axis of rotation. Since the aim is to stabilize the needle 23 in the north direction determined by the second magnetic sensor 4' in the most intuitive way possible according to a movement corresponding to a physical reality, the torque values 451' will thus oscillate between positive and negative values as a function of the relative angle 451, materializing a restoring force exerted on the needle 23 in one direction or the other.
  • step 5004 aims to determine the frequency of motor steps 633 of the third motor 63. This step comprises a first sub-step of calculating the simulated angular acceleration of the display means 703′, in this case the angular acceleration of needle 23 of compass 21 according to the fundamental principle of dynamics applied to solid-state physics, formalized by the following second Newtonian equation 700': $$703\prime =\left(451\prime -703"\right)/704,$$
    
  the coefficient 704 corresponding to the simulated moment of inertia of the system (usually represented by the letter J), which in this case models the moment of inertia of a rotating system associated with the north indicator needle of the compass 23 around its axis of rotation, 451' being the fictitious torque which is applied to it as a function of the sine of the angle formed by the needle 23 of the compass 21 and the direction of North. Similar to the first Newtonian equation 700 above to determine the movement of the minute hand 21, the coefficient 704 of the simulated rotating system is here again chosen, within the framework of the second Newtonian equation 700', preferably much greater than the real moment of inertia of the compass needle 23, in order to give this needle the behavior of a more massive system. According to the preferred embodiment illustrated, and similarly to the preferred embodiment described previously for the correction of time indications, a fictitious torque 703" proportional to the simulated angular speed 703, to determine this time the angular speed 233 of the 'compass needle 23', was introduced to model a fluid friction gradually slowing down the movement of this needle 23. Similar to the torque value 401', the torque value 703" is obtained by multiplying the simulated angular velocity 703 by a proportionality coefficient 702, called fluid friction coefficient. According to a preferred variant of the invention, each motor step causes a movement of the needle 23 of the compass through a restricted angular sector, in order to make the movement of the needle as smooth as possible. In order to make the scrolling of this compass needle 23 as fluid as possible, the angular increment value of each step is chosen, preferably less than or equal to 1 degree. In other words, each motor step of the motor 63 causes the needle 23 of the compass to rotate by an angular value corresponding to one sixth of that corresponding to one minute, so that the motor steps are almost no longer perceptible to the naked eye.

We can consider a less fine resolution, or equivalent to those of the other motors used for the movement of the hands of the 21 minutes or 22 hours; it is possible for example to conceive for this purpose that the motor 63 associated with the movement of the needle of the compass 23 is the motor 61 associated with the minute hand 21, and that this minute hand 21 is simultaneously used as a hand compass 23 in a specific dedicated operating mode.

To simplify the calculations, the second Newtonian equation 700' used to determine the movement of the needle 23 of the compass 21 could also be simplified by an equivalent rewriting requiring no division operation.

The method for determining the movement of a compass needle 23 makes it possible to considerably smooth out its movement, which is often jerky on electromechanical watches. The electronic compass described according to the preferred embodiment above comprises a mechanical display member 2, namely a needle, and can therefore be easily integrated for example into a wristwatch. In this case, the minute hand 21 can advantageously be used as a compass hand 23.

The above method could also be used by those skilled in the art in other types of similar applications, compatible with electromechanical watches, where the movement of the hands is used to give other types of information, such as the altitude for an altimeter or depth for a depth gauge.

Claims (11)

1. A method for determining a movement of variable and continuous velocity of analog display means (2) of an electromechanical timepiece, the timepiece further including means (1) for activating display means (2), the activation means (1) could be actuated by a user, a sensor (4, 4') of the movement of the activation means (1), a calculating unit (5), and motor means (61, 62, 63) adapted to impart a movement of variable and continuous velocity to said display means (2), the method comprising a first step of measuring by the sensor (4, 4') the movement of said activation means (1), a second step of modelling at least one simulated mechanical torque and/or force value (401', 451') from values measured by the sensor (4, 4') in the first step, a third step (5001, 5004) of solving a Newtonian equation of the movement (700, 700') from said simulated mechanical torque and/or force values (401', 451') in the second step, said third step (5001, 5004) allowing calculating a simulated velocity (703) for said display means (2) whose acceleration and deceleration is proportional to the torque or to the force.
2. The method for determining a movement of continuous velocity of display means (2) according to claim 1, the simulated acceleration (703) of said display means (2) being proportional to a value (401, 451) corresponding to a physical quantity.
3. The method for determining a movement of variable and continuous velocity of display means (2) according to one of the preceding claims, the physical quantity being a velocity, a magnetic field, an altitude, a depth, a frequency or a geometric angle.
4. The method for determining a movement of variable and continuous velocity of display means (2) according to one of the preceding claims, a second mechanical torque and/or force value (703") being used to determine the movement of the display means (2), said second mechanical torque and/or force value (703") modelling fluid frictions.
5. The method for determining a movement of variable and continuous velocity of display means (2) according to one of the preceding claims, further comprising a step of determining an impulse frequency (4001) calculated from an angular velocity (111) of a crown (11).
6. An electromechanical timepiece including analog display means (2), means (1) for activating the display means (2), the activation means (1) could be actuated by a user, a control device (3) provided with a sensor (4, 4') of the movement of the activation means (1), and motor means (61, 62, 63) adapted to impart a movement of variable and continuous velocity to said display means (2), and wherein the control device (3) comprises a calculating unit (5) and a memory unit (7) comprising instructions which, when executed by said calculating unit (5), lead the control device (3) to calculate a simulated velocity (703) for said display means (2) according to the method of one of claims 1 to 5.
7. The electromechanical timepiece according to claim 6,, characterised in that the control device (3) comprises at least a first and/or a second sensor (4, 4') measuring first physical magnitudes, said first physical magnitudes being converted into second physical magnitudes (401, 451) from which said mechanical torque and/or force values (401', 451') are calculated by pre-processing circuits upstream of the calculating unit (5).
8. The electromechanical timepiece according to one of claims 6 or 7, characterised in that the control device (3) actuates at least a first motor (61) driving said display means (2), said first motor (61) further determining a maximum scrolling velocity (611') for said display means (2).
9. The electromechanical timepiece according to one of claims 6 to 8, characterised in that the control device (3) simultaneously actuates a plurality of motors (61, 62) each dedicated to distinct display means (2).
10. The electromechanical timepiece according to one of claims 7 to 9, characterised in that the acceleration and/or deceleration of said display means (2) is calculated according to an impulse frequency (401) measured by said first sensor (4) or according to a relative angle (451) between said display means (2) and a direction of north determined by said second sensor (4').
11. The electromechanical timepiece according to claim 10, said display means (2) being hands (21, 22, 23), characterised in that the simulated angular acceleration (703') of at least one of said hands (21, 22, 23) is calculated according to a first torque value (401', 451') proportional to said impulse frequency (401) or said relative angle (451), and according to a second torque value (703") proportional to the simulated angular velocity (703) of said hand (21, 23).

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