EP3985454B1 - Winding device for an automatic watch - Google Patents

Description

Field of the invention

The invention relates to an automatic device for winding automatic watches.

The invention also relates to a universal device for winding and resetting the time of a watch, comprising such an automatic device for winding watches.

The invention relates to the field of smart devices, such as smart winders, for keeping watches immediately fit for service, displaying the correct time, and with a sufficient power reserve to wear them for a few hours, while avoiding premature wear of the watch by incessant and unnecessary windings.

Background of the invention

The document EP3339984 on behalf of The Swatch Group Research and Development Ltd describes an intelligent watch winding device. This device is constantly being improved.

In particular, one of the developments concerns an intelligent winder, based on the limitation of unnecessary winding of automatic watches, and whose main purpose is to limit the recharging of the automatic barrel of the watch to what is strictly necessary, to avoid any premature wear of the watch. , as a result of excessive pumping over.

To identify whether a watch is fully charged, the amplitude of the balance-spring is measured by an acoustic method. However, it remains difficult to perform an accurate and reliable measurement of the amplitude, due to the background noise, at a reasonable cost, and with low power consumption. In addition, for optimal accuracy, this method requires contact with the measured watch, or at least the installation of an aerial microphone very close to the resonator of the watch, in a low-noise environment.

Summary of the invention

The invention proposes to measure the rate of winding of a mechanical watch with automatic winding, by measuring the influence that the winding mechanism has on the automatic device for winding automatic watches, hereinafter referred to as winder.

An advantageous application relates to the production of an intelligent winding mechanism with torque measurement.

To this end, the invention relates to a winding device for an automatic watch with a mobile oscillating weight, according to claim 1.

Brief description of the drawings

• la figure 1 représente, de façon schématisée et en vue de face, le dos d'une montre automatique, positionnée avec le plan de sa masse oscillante parallèle au champ de gravité, dans un état désarmé de la montre, dans lequel l'angle mort est presque nul ;
• la figure 2 représente, de façon similaire à la figure 1, la même montre dans un état complètement armé, où l'angle mort est maximal ;
• la figure 3 est une courbe qui représente, en ordonnée la vitesse du remontoir, qui est variable en fonction du nombre de tours de remontoir en abscisse ;
• la figure 4 est un schéma-blocs qui comporte les différents moyens de mesure utilisables pour mesurer la variation du couple résistant qui est opposé aux moyens de motorisation, et donc le degré d'armage de la montre ;
• la figure 5 est une vue en coupe d'un porte-montre adapté à une montre automatique comportant un fond transparent, sous lequel une caméra suit la valeur de l'angle mort ;
• la figure 6 représente, de façon schématisée, en perspective éclatée, un dispositif de remontoir selon l'invention, dans une variante à mesure optique.

Other characteristics and advantages of the invention will appear on reading the detailed description which follows, with reference to the appended drawings, where:

• there figure 1 represents, schematically and in front view, the back of an automatic watch, positioned with the plane of its oscillating mass parallel to the field of gravity, in a disarmed state of the watch, in which the blind spot is almost zero ;
• there figure 2 represents, similarly to the figure 1 , the same watch in a fully armed state, where the blind spot is maximum;
• there picture 3 is a curve which represents, on the ordinate, the speed of the winding device, which is variable according to the number of turns of the winding device on the abscissa;
• there figure 4 is a block diagram which comprises the various measurement means which can be used to measure the variation of the resistive torque which is opposed to the motorization means, and therefore the degree of winding of the watch;
• there figure 5 is a sectional view of a watch holder suitable for an automatic watch comprising a transparent back, under which a camera tracks the value of the blind spot;
• there figure 6 represents, schematically, in exploded perspective, a winding device according to the invention, in a variant with optical measurement.

Detailed Description of Preferred Embodiments

The invention proposes to complete the acoustic measurement of the amplitude with a measurement of the influence that the winding state of the watch has on the winding mechanism. Indeed, the winding angle of the oscillating weight (also called dead angle) increases with the rate of winding, since the mainspring opposes the torque of the weight.

The center of gravity CG of the oscillating mass 10 is eccentric, and is located, with respect to its axis of rotation, on a radial which is here called the radial of the center of mass RCM. If, in a simplified approach, friction is neglected, the system of forces applying to the oscillating weight 10 boils down to the opposition between the restoring torque exerted by the barrel wheel on the one hand, and the torque exerted by the gravitation on the oscillating mass 10. When an automatic watch is placed with the plane of the oscillating mass parallel to the field of gravity, the term "dead angle" is used to refer to the angle AM that this radial of the center of mass RCM makes with the vertical V of the place.

When the watch is disarmed, and an hourly torque R is applied to it in this same plane to recharge it, this blind angle AM is very small: the straight edge 11 that an oscillating mass 10 generally comprises remains almost horizontal, such than visible on the figure 1 .

On the other hand, when the watch is fully armed, and under the same conditions, and as visible on the picture 2 , the dead angle AM is considerably higher (for example 24° more for a standard ETA 2824 movement, well known to those skilled in the art and very widespread), since the torque of the barrel spring is maximum and opposes to the torque of the oscillating mass 10: balance is only possible with a large angle so that the gravitational torque balances that coming from the barrel.

In short, this change of angle has the effect of shifting the center of mass of the entire watch, which has a measurable unbalance effect on the crown 100 on which the watch is placed, through a watch holder 1 .

Three methods, non-limiting, and which can be combined, are proposed to measure this effect.

Velocity measurement is advantageous because it is an efficient and inexpensive method. Winder 100 is equipped with a direct current motor 21 not speed-controlled, only the supply voltage is constant (imposed by the algorithm). When the watch is unloaded, the torque opposed by the watch is at a minimum, and the winding speed is at a maximum. When the watch is fully wound, the torque opposed by the watch is at maximum, and the winding speed is at minimum. There picture 3 shows the evolution of the speed of rotation of the winder (in turns per second) as a function of the number of turns of the winder 100, during the complete winding of a watch. It can be seen that this rotation speed decreases by around 0.8% when the watch is fully charged (after around 2000 turns of the winding mechanism). In this embodiment, the speed of the winding mechanism 100 is simply performed using a fixed optical sensor 31 and a mobile marker 32 integral with the rotating watch holder 1.

Torque measurement is an effective method but more expensive than the previous one. The torque opposed by the oscillating mass 10 increases when the winding increases, until it reaches a plateau when the watch is fully wound. The torque can be measured with a torque tester or torque meter mounted on the watch holder. The advantage of a torque meter is its high sensitivity.

Measuring the current injected into the winder motor is a cheap but tricky method unless you average long enough. The current of a DC motor as used in the winder is proportional to its load, and therefore to the torque opposed by the rotor composed of the watch holder and the watch with its oscillating mass 10. Measurements show that a winder fitted with a discharged watch consumes around 2 mA (under 1V), with periodic variations that can reach +/- 0.5 mA (i.e. +/- 25%) during one turn of the watch holder. It can be shown that the average current should theoretically increase by only 40 µA when the watch is fully charged, an average increase of only 2% compared to the reference 2 mA. If the current measurement is averaged long enough (typically several revolutions, i.e. a few tens of seconds, which corresponds to a low-pass filter, which cancels the periodic variations), this 2% increase in the average current becomes possible to detect by relation to noise.

Thus, more particularly, the invention relates to a winding device 100 for an automatic watch with a mobile oscillating weight.

This device 100 comprises at least one watch holder 1, which is arranged to carry at least one automatic watch. The device 100 comprises motorization means 2 for driving, in particular at least in rotation, the at least one watch holder 1, and more particularly each watch holder 1 that it comprises.

According to the invention, the device 100 comprises measuring means 3, which are arranged to measure the variation of the resistive torque which is opposed to the motorization means 2 by a moving assembly consisting, on the one hand, of all the watch holders 1 driven by the motorization means 2, and on the other hand all the watches that all of these same watch holders 1 wear, depending on the degree of winding of the watches. And these measuring means 3 comprise speed measuring means 4 for determining the speed and/or the variation in the speed of the means of motorization 2, and/or comprise means for measuring the torque 5 to determine the value of the torque and/or the variation of the torque at the level of at least one watch holder 1, and/or comprise means for measuring the current 6 to determine the value of the current and/or the variation of the current at the level of at least one electric motor 21 that comprises the motorization means 2.

More particularly, the measuring means 3 comprise such speed measuring means 4, which comprise fixed optical means 31 arranged to follow a mobile marker 32 which a watch holder 1 comprises, and which are coupled with a time base 9 , which the winding device 100 comprises or with which the winding device 100 is interfaced. Alternatively, these optical means 31 are arranged to follow an oscillating mass 10 of at least one watch comprising a transparent back allowing the oscillating mass 10, or, more particularly, of each watch equipped with such a transparent back.

Thus, more particularly, at least one watch holder 1 is arranged to make visible the oscillating weight 10 of each watch carrying a transparent back that it carries, and viewing means 33 are arranged to follow and/or determine the angular position of an oscillating mass 10 of a given watch between a dead angle corresponding to the disarmed state of the watch and a limit winding angle corresponding to the fully armed state of the watch. And the measuring means 3 are then advantageously arranged to send a stop signal to the motorization means 2 when the limit winding angle is reached, to avoid any superfluous winding, and therefore any wear of the watch.

More particularly, the motorization means 2 comprise a direct current electric motor 21, not speed-controlled.

More particularly, the measurement means 3 then comprise speed measurement means 4, which are arranged to send a stop signal to the motorization means 2 when the speed of the motorization means 2 is lower, by a value pre- determined, at the speed of the motorization means 2 at the start of the cycle when at least one watch carried by at least one watch holder 1 is in an unarmed state. More particularly, this pre-determined value is between 0.2% and 1.4%. More particularly still, the pre-determined value is between 0.6% and 1.0%.

More particularly, the measurement means 3 comprise torque measurement means 5, which are arranged to send a stop signal to the motorization means 2 when the value of the measured torque is stabilized with a variation less than a pre-determined threshold. , such as 1.0% in a particular non-limiting variant.

More particularly, the measurement means 3 comprise torque measurement means 5, which are arranged to determine the actual angular position of the center of mass of the moving assembly mentioned above, to compare it with a theoretical angular position corresponding to the fully armed state of each watch, and are arranged to send a stop signal to the motorization means 2 when these actual and theoretical positions are equal.

More particularly, the measurement means 3 comprise current measurement means 6 for determining the value of the current and/or the variation of the current at the level of the motor which the motorization means 2 comprise, in particular an electric motor 21, and which constitute torque measurement means 5.

More particularly, the measuring means 3 comprise such current measuring means 6 to determine the value of the current and/or the variation of the current at the level of the electric motor 21, and which are arranged to send a stop signal to the means of motorization 2 when the current consumption is, for a period greater than 80 seconds, more than 4.0% higher than the consumption at the start of the cycle when at least one watch worn by at least one watch holder 1 is in an unarmed state . More particularly, these measurement means 3 are arranged to send this signal when the current consumption is, for a period of more than 40 seconds, greater than 2.0% higher than the consumption at the start of the cycle when at least one watch worn by at least least one watch holder 1 is in an unarmed state.

More particularly, the measuring means 3 are arranged to determine a difference in resistance according to the direction of rotation of a watch holder 1, and to impose a rotation of the watch holder 1 in the direction in which it presents the greatest resistance. This makes it possible to determine the presence of automatic watches which are designed for winding in one direction only, and for free-wheeling movement in the other direction; thus each movement imparted to the watch holder 1 is effective since it is used for rearming.

More particularly, at least one watch holder 1 carries a single watch. More particularly still, each watch holder 1 carries a single watch.

More particularly, the winding device 100 comprises a single watch holder 1.

• pas de nécessité d'installer de microphone aérien ou de contact;
• indépendance par rapport au bruit ambiant, qui constitue en général l'entrave majeure à des mesures précises et fiables;
• pas de nécessité d'installer, au niveau du porte-montre, une deuxième circuit électronique embarqué alimenté sans fil;
• facilité de la mesure de la vitesse, avec un algorithme très simple en comparaison avec celui nécessaire pour la mesure acoustique de l'amplitude;
• grande résolution des mesures de vitesse ou de couple, toutefois avec un bruit potentiellement élevé;
• une mesure relative de l'effet sur le remontoir fonctionne avec n'importe quelle montre automatique;
• ces mesures permettent de déterminer rapidement le bon sens de remontage.

The invention has several major advantages, whatever its embodiment:

• no need to install aerial or contact microphone;
• independence from ambient noise, which is usually the major impediment to accurate and reliable measurements;
• no need to install, at the level of the watch holder, a second on-board electronic circuit powered wirelessly;
• ease of velocity measurement, with a very simple algorithm compared to that needed for acoustic amplitude measurement;
• high resolution of speed or torque measurements, however with potentially high noise;
• a relative measurement of the effect on the winder works with any automatic watch;
• these measurements make it possible to quickly determine the correct winding direction.

Claims (16)

1. Winding device (100) for an automatic watch with a mobile oscillating mass, including at least one watch holder (1) arranged to carry at least one automatic watch, and including motorisation means (2) for driving said at least one watch holder (1), characterised in that said device (100) includes measuring means (3) which are arranged to measure the variation in the resistive torque which is opposed to said motorisation means (2) by a mobile equipment consisting of, on the one hand, all said watch holders (1) driven by said motorisation means (2), and on the other hand all the watches that all said watch holders (1) driven by said motorisation means (2) carry, depending on the degree of winding of said watches, and in that said measuring means (3) include speed measuring means (4) to determine the speed and/or the variation in the speed of said motorisation means (2), and/or include torque measuring means (5) to determine the value of the torque and/or the variation in the torque at least at one said watch holder (1), and/or include current measuring means (6) to determine the value of the current and/or the variation in the current at least at one electric motor (21) that said motorisation means (2) include.
2. Winding device (100) according to claim 1, characterised in that said measuring means (3) include said speed measuring means (4) which include fixed optical means (31) arranged to follow a mobile locator (32) that a said watch holder (1) includes, and coupled with a time base (9) that said winding device (100) includes or with which said winding device (100) is interfaced, or to follow an oscillating mass (10) of a said watch including a transparent back allowing the observation of said oscillating mass (10).
3. Winding device (100) according to claim 2, characterised in that at least one said watch holder (1) is arranged to make visible the oscillating mass (10) of each watch carrying a transparent back that it carries, and in that viewing means (33) are arranged to follow and/or determine the angular position of an oscillating mass (10) of a given watch between a dead angle corresponding to the unwound state of said watch and a limit winding angle corresponding to the fully wound state of said watch, and in that said measuring means (3) are arranged to send a stop signal to said motorisation means (2) when said limit winding angle is reached.
4. Winding device (100) according to one of claims 1 to 3, characterised in that said motorisation means (2) include a direct current electric motor (21) which is not speed-controlled.
5. Winding device (100) according to claim 4, characterised in that said measuring means (3) include said speed measuring means (4) which are arranged to send a stop signal to said motorisation means (2) when said speed of said motorisation means (2) is less, by a predetermined value, than the speed of said motorisation means (2) at the start of the cycle when at least one watch carried by at least one said watch holder (1) is in an unwound state.
6. Winding device (100) according to claim 5, characterised in that said predetermined value is comprised between 0.2% and 1.4%.
7. Winding device (100) according to claim 6, characterised in that said predetermined value is comprised between 0.6% and 1.0%.
8. Winding device (100) according to claim 1, characterised in that said measuring means (3) include said torque measuring means (5), which are arranged to send a stop signal to said motorisation means (2) when the value of the measured torque is stabilised with a variation less than 1.0%.
9. Winding device (100) according to claim 1 or 8, characterised in that said measuring means (3) include said torque measuring means (5), which are arranged to determine the real angular position of the centre of mass of said mobile equipment, to compare it with a theoretical angular position corresponding to the fully wound state of each said watch, and are arranged to send a stop signal to said motorisation means (2) when said real and theoretical positions are equal.
10. Winding device (100) according to claim 8 or 9, characterised in that said measuring means (3) include said current measuring means (6) to determine the value of the current and/or the variation in the current at said electric motor (21), and which constitute said torque measuring means (5).
11. Winding device (100) according to claims 1 and 4, characterised in that said measuring means (3) include said current measuring means (6) to determine the value of the current and/or the variation in the current at said electric motor (21), and arranged to send a stop signal to said motorisation means (2) when the current consumption is, for a duration greater than 80 seconds, more than 4.0% higher than the consumption at the start of the cycle when at least one watch carried by at least one said watch holder (1) is in an unwound state.
12. Winding device (100) according to claim 11, characterised in that said measuring means (3) are arranged to send a said stop signal to said motorisation means (2) when the current consumption is, for a duration greater than 40 seconds, more than 2.0% higher than the consumption at the start of the cycle when at least one watch carried by at least one said watch holder (1) is in an unwound state.
13. Winding device (100) according to one of claims 1 to 12, characterised in that said measuring means (3) are arranged to determine a difference in resistance according to the direction of rotation of said watch holder (1), and to impose a rotation of said watch holder (1) in the direction wherein it has the greatest resistance.
14. Winding device (100) according to one of claims 1 to 13, characterised in that at least one said watch holder (1) carries a single watch.
15. Winding device (100) according to claim 14, characterised in that each said watch holder (1) carries a single watch.
16. Winding device (100) according to one of claims 1 to 15, characterised in that said winding device (100) includes a single said watch holder (1).

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