EP3489762B1 - Operating system for a timepiece - Google Patents

Description

Technical area

The present invention relates to the field of watchmaking. It relates more particularly to a maintenance system for a watch movement.

State of the art

So-called "trigger" escapements have been known for more than two centuries. This type of maintenance system differs from the usual Swiss lever escapement in that the impulses which maintain the oscillations of the balance come directly from the finishing gear via a impulse wheel, and are not transferred. through an anchor. To this end, the impulses are given by the teeth of the impulse wheel directly to a rotating part of the balance. A trigger, which is controlled by a pin or the like integral in rotation with the balance, blocks the impulse wheel and releases it once per oscillation. The document CH 3299 describes an exhaust of this type.

These escapements have found application in particular in marine chronometers, thanks to their excellent chronometric properties, as well as their improved efficiency compared to a Swiss lever escapement. Other less relevant prior art constructions are also disclosed by the documents. EP 3153935 , EP 3121660 , EP 2290476 and CH 709752 .

However, the fact that the time is counted at the level of the finishing gear still leaves room for an improvement in the level of the chronometric properties of the movement.

The aim of the invention is therefore to provide a maintenance system for a timepiece in which the aforementioned defects are at least partially overcome.

Disclosure of the invention

More precisely, a first aspect of the invention relates to a system for maintaining an oscillator for a timepiece such as a wristwatch or pocket watch, this oscillator comprising an inertial mass such as a balance arranged for oscillate under the effect of a restoring force provided by an elastic element such as a spiral spring. Alternatively, the inertial mass can be a tuning fork (the arms of which also constitute the elastic elements) or any other suitable construction.

This system comprises an impulse wheel intended to be in direct or indirect kinematic connection with an energy source such as a mainspring housed in a barrel, the impulse wheel being arranged to supply impulses to said inertial mass in order to to maintain it in oscillation, as well as a locking member arranged to block and sequentially release said impulse wheel directly or indirectly.

According to the invention, said system further comprises a control wheel arranged to control said blocking member to block and release said impulse wheel in synchronism with the oscillations of said inertial mass, as well as a transmission member arranged to driving said control mobile in rotation at a rate of one step in a (single) predetermined direction by oscillation of said inertial mass.

In doing so, the time counting is dissociated from the cog linking the energy source to the impulse wheel, commonly called the "finishing cog", which improves the chronometric properties of the system since there is less disturbance of the oscillations. of inertial mass.

Advantageously, said control mobile comprises at least one control cam which cooperates in particular indirectly with said impulse wheel, for example by means of a lever comprising a feeler arranged to cooperate with said cam, as well as at least one blocking element arranged to block and to release said impulse wheel under the control of said cam. This locking element can be for example a fork or a trigger whose angular position is controlled by said control cam, which rotates in discrete steps always in the same direction of rotation.

Advantageously, said transmission member is a lever or a beam arranged to cooperate with said control wheel set as well as with said inertial mass, in particular with an element carried by the latter. An element integral with the inertial mass can thus drive the rocker or beam once by oscillation, this drive being transmitted to the control mobile in order to make it pivot.

Advantageously, a display can be arranged to be driven either by said transmission member and / or by said control mobile. Alternatively, the display can be arranged to be driven by an energy source under the control of an element carried by said transmission member, or by said control wheel, or by the inertial mass. In doing so, these displays are not driven by the finishing gear train, which can therefore present gear ratios adapted exclusively to the drive of the impulse wheel in order to maximize the efficiency and the power reserve of the system.

Brief description of the drawings

• Figures 1 à 3 sont des vues schématiques d'un système d'entretien selon le premier aspect de l'invention dans trois phases de fonctionnement ;
• Figure 4 est une vue schématique d'une variante d'un système d'entretien selon le premier aspect de l'invention ;
• Figure 5 est une vue schématique d'encore une variante d'un système d'entretien selon le premier aspect de l'invention ;
• Figure 6 est une vue schématique d'encore une variante d'un système d'entretien selon le premier aspect de l'invention ;
• Figure 7 est une vue schématique d'une variante d'un système d'entretien selon le premier aspect de l'invention et selon un deuxième aspect ne faisant pas partie de l'invention ;
• Figures 8a et 8b sont des vues schématiques en coupe d'une partie du système de la figure 7 ;
• Figures 9 et 10 sont des vues schématiques en coupe de deux variantes alternatives de la partie du système représentée sur les figures 8a et 8b ;
• Figure 11 est une vue schématique d'une variante d'un système d'entretien selon ledit deuxième aspect ;
• Figure 12 une vue schématique d'encore une variante d'un système d'entretien selon ledit deuxième aspect ;
• Figure 13 une vue schématique d'encore une variante d'un système d'entretien selon ledit deuxième aspect ;
• Figure 14 une vue schématique d'encore une variante d'un système d'entretien selon ledit deuxième aspect ; et
• Figure 15 une vue schématique d'encore une variante d'un système d'entretien selon le premier aspect de l'invention.

Other details of the invention will emerge more clearly on reading the following description, given with reference to the appended drawings in which:

• Figures 1 to 3 are schematic views of a maintenance system according to the first aspect of the invention in three phases of operation;
• Figure 4 is a schematic view of a variant of a maintenance system according to the first aspect of the invention;
• Figure 5 is a schematic view of yet another variant of a maintenance system according to the first aspect of the invention;
• Figure 6 is a schematic view of yet another variant of a maintenance system according to the first aspect of the invention;
• Figure 7 is a schematic view of a variant of a maintenance system according to the first aspect of the invention and according to a second aspect not forming part of the invention;
• Figures 8a and 8b are schematic sectional views of part of the system of the figure 7 ;
• Figures 9 and 10 are schematic sectional views of two alternative variations of the part of the system shown in the figures 8a and 8b ;
• Figure 11 is a schematic view of a variant of a maintenance system according to said second aspect;
• Figure 12 a schematic view of yet another variant of a maintenance system according to said second aspect;
• Figure 13 a schematic view of yet another variant of a maintenance system according to said second aspect;
• Figure 14 a schematic view of yet another variant of a maintenance system according to said second aspect; and
• Figure 15 a schematic view of yet another variant of a maintenance system according to the first aspect of the invention.

Embodiments of the invention

The figure 1 schematically illustrates a first embodiment of a maintenance system 1 according to the first aspect of the invention. It should be emphasized that all the figures are purely schematic, are not to scale, and serve to illustrate the operation of the various variants of the invention in a clear manner. For this purpose, some elements have been represented with a relative size which is larger than in reality, some others with a smaller relative size. On the other hand, an arrangement of two elements in two different planes is made evident by means of overlaps of these elements. Those skilled in the art know how to size, shape and position the elements so that the system 1 operates correctly as described below, which also applies to the level of conventional kinematic chains which have been shown schematically by arrows. In addition, any direction, orientation etc. mentioned below is to be considered in relation to the representations of the figures. Finally, it is noted that components performing a similar function have been indicated by the same reference signs, even if they are structurally different, in order to make these similar functionalities appear more clearly.

The maintenance system 1 shown in figure 1 is arranged to maintain an inertial mass 3 in oscillation, such as a balance associated with a return spring (not shown), such as a spiral spring, in a known manner. The inertial mass 3 and its return spring may be integral or may be separate elements. The inertial mass 3 is thus arranged to perform oscillations on either side of a neutral position. Alternatively, the inertial mass can be a tuning fork or the like.

In order to supply energy to the inertial mass 3, the system 1 comprises an impulse wheel 5, which is in kinematic connection with an energy source 7 such as a barrel, an electric motor or the like, by the 'intermediary of a finishing gear 8. The fifteen teeth 5a of the impulse wheel 5 are arranged to enter the path of an impulse paddle 9 carried by a plate 11 integral in rotation with the inertial mass 3, in order to transmit force to the latter as generally known in the context of a detent escapement. The number of teeth 5a can be chosen at will. It is also possible to interpose a constant force system between the impulse wheel 5 and the energy source 7 and / or one to integrate a winding system of equality in the impulse wheel 5. It is It is also possible that the impulse wheel 5 cooperates indirectly with the impulse paddle 9, for example by means of an ad hoc lever.

The positions of the various elements of the system 1 correspond to their state just before an impulse, and it is clear that the impulse vane 9 is free and can therefore move without hindrance by the teeth 5a of the impulse wheel 5.

The impulse wheel 5 is integral in rotation with a locking wheel 13, which cooperates with a locking member in the form of a lever 12 comprising a fork 15 at one of its ends, the latter being arranged to lock and release the locking wheel 13 when the fork 15 oscillates from one extreme angular position to the other. The fork 15, as well as the shape of the teeth of the locking wheel 13 are purely illustrative, and various other solutions are also possible. For example, one could use a trigger instead of a fork 15, and the trigger or the fork 15 can alternatively cooperate directly with the teeth 5a of the impulse wheel.

The fork 15 is controlled to pivot about its axis of rotation 15a by a control wheel 16.

In the illustrated embodiment, the control mobile 16 comprises a control cam 19 which is followed by a feeler 15b that includes one end of the fork 15 under the action of a return spring 14. When the control cam 19 rotates, the fork 15 oscillates between two extreme angular positions, as is well known and will follow clearly below. To this end, the control cam 19 has three bearings with a lower radius, as well as three bearings with a greater radius, in order to control the oscillation of the fork 15, the shape of the control cam 19 being chosen in such a way. that the probe 15b can change bearings when the control cam 19 rotates.

The cam 19 is integral in rotation with a control wheel 21, comprising a number of teeth which is an integer multiple of the number of sections of the cam 19. In the illustrated arrangement, the cam 19 comprises three sections with a larger radius and three sections with a smaller radius (six sections in total), and the drive wheel 21 has 12 teeth. Consequently, the fork 15 will pass from one of its extreme angular positions to the other when the control wheel 21 has turned by an angle corresponding to two steps of its toothing. The control wheel 21 can be positioned by a jumper, friction or other means (not shown) to ensure that it does not rotate inadvertently. In the variant illustrated, the control wheel 21 has twelve teeth, but the manufacturer can choose the number of the latter according to his needs.

The control wheel 21 is rotated by a transmission member 23, which is arranged to transmit the pulses received from the inertial mass 3 to the control wheel 21, each pulse driving the latter at the rate of one step (or d 'a tooth).

To this end, in the variant illustrated, the transmission member 23 is a beam, a first end 23a of which is arranged to penetrate into the teeth of the control wheel 21 and to cooperate with its teeth in order to advance the wheel 21 in steps. of a tooth, and a second end 23b of which is arranged to be driven by a finger 25 (or ankle) carried by an additional plate 27 integral in rotation with the inertial mass 3. The two plates 11, 27 are arranged to position the impulse paddle 9 and finger 25 in different planes, and may be integral with each other.

The transmission member 23 is guided by an ad hoc guide 29, such as for example a guide based on flexible pivots (hereinafter “flexures”). Such guides (such as necks, flexible blades, etc.) are known, in particular in the work Design of flexible guides, Simon Henein, Meta Collection, Presses polytechniques et universitaire romandes, 2001 , from which the manufacturer can choose a guidance that meets his needs. Therefore, it is not necessary to describe the guidance here except for what refers to its properties. These will follow clearly thereafter.

In the embodiment of the figure 1 , the system 1 is integrated into a movement comprising two displays, a first display 31 driven in a conventional manner from the finishing gear 8, and a second display 33 driven from the mobile control unit 16, which comprises an additional wheel 35 provided for this purpose. Either of these displays 31, 33 can be omitted.

Having now described the kinematics of system 1, it is noted again that the various elements are not represented to scale. In particular, the second display 33, the transmission member 23, the control mobile 16 as well as the part of the fork which interacts with the latter are of size and inertia reduced compared to conventional watch components, and can thus have dimensions (diameter, length) in the plane of the system 1 which are for example less than 2.5 mm. To this end, they can be constructed not only of metal, alloy or composite, but advantageously also of non-metallic material, such as for example polymer, silicon, silicon oxide, silicon nitride, silicon carbide, alumina in all its forms. , natural or synthetic diamond, or combinations of these materials (for example silicon coated with another material mentioned). These materials can be non-magnetic. In order to reduce friction and thus reduce energy consumption, flexible guides (where appropriate) and / or bearings comprising contact surfaces of natural or synthetic diamond, or any other self-lubricating material can be used.

The functioning of the figure 1 will now be described with reference to figures 1 to 3 . Subsequently, only the reference signs mentioned in the text are reproduced so as not to overload the figures, the other components being corresponding to those of the figure 1 .

In the orientation of the elements of the figure 1 , the impulse wheel 5 is blocked by a blocking member. The latter is a beak formed by the branch of the fork 15 which is closest to the inertial mass, and the latter is in the process of pivoting in the counterclockwise direction. The control mobile 16 is at rest, and at the next step, the probe 15b will transit from a low bearing to an upper bearing of the control cam 19. At the time illustrated, the finger 25 is almost in contact with the second end 23b of the transmission member 23 which is in its rest position, and the impulse vane 9 has just entered the path of the teeth 5a of the impulse wheel.

Looking now at the figure 2 , the transmission member 23 has been moved axially by the finger 25 so that its first end 23a has cooperated with a tooth of the control wheel 21 and has driven the latter (as well as the entire control wheel 16 ) in the counterclockwise (according to the orientation of the figures). The control mobile 16 is thus between two stable states, and the probe 15b has just mounted on a top bearing of the control cam 19. The flexibility of the flexible guide 29 perpendicular to the axis of the transmission member 23 allows its first end to rise to allow the next tooth of the control wheel 21 to position itself.

The fact that the probe 15b has just mounted on a top bearing of the control cam 19 forced the fork 15 to adopt its other extreme angular position, which allowed the impulse wheel 5 to perform a 1 / 15 ^th round, in which one of its teeth applies a pulse to the impulse pallet 9.

The figure 3 illustrates the situation when the control mobile 16 has reached its next stable orientation, in which it has been positioned by the jumper (or similar) not shown. The impulse wheel 5 is again blocked by the other nose of the fork, in a manner similar to a conventional anchor. The path of the impulse paddle 9 is again free.

When the finger 25 is no longer in contact with the transmission member 23, the latter re-adopts its rest position, as illustrated in FIG. figure 3 .

The inertial mass 3 continues its course in the counterclockwise direction, ends its alternation, and returns back in the clockwise direction. The curved shape of the rear face of the finger 25 is adapted so that, when it comes into contact with the transmission member 23 during its clockwise travel, the latter is slightly raised in order to allow the finger 25 to pass, without disturbing the oscillation of the inertial mass 3. For this purpose, the flexible guide 29 is also arranged to allow this lifting of the transmission member 23.

Then, the cycle is repeated, the control cam 19 ensures that the fork 15 changes state and releases the impulse wheel 5 one oscillation out of two of the inertial mass: in fact, the system is designed so that the cam of control 19 does not cause a change in position of the fork 15 at the next rotation of 1/12 of a revolution of the control mobile following the following oscillation, given that the probe 15b remains on the same level of the cam 19. By modifying the shape of the control cam 19, in particular as regards the number of bearings, and the shape and the number of teeth of the control wheel 21, the number of oscillations of the inertial mass 3 by impulse can be varied according to the needs of the builder. If we increase the number of oscillations between the pulses, the maintenance system 1 becomes more efficient, the power reserve of the movement increases, and the oscillations of the inertial mass 3 are less disturbed, which can improve the isochronism of motion. However, the oscillation amplitude of the inertial mass 3 is reduced accordingly.

The figure 4 illustrates a variant of the arrangement of figures 1 to 3 , which differs from the latter mainly in that the transmission member 23 is mounted to tilt about a pivot point 23c. Consequently, when the finger 25 actuates the transmission member 23, its free end 23d cooperates with a tooth of the control wheel 21 in the same way as in the variant of figures 1 to 3 . In order to allow the free end 23d of the control member 23 to retract when the next tooth of the control wheel 21 arrives, the transmission member 23 comprises a flexible part 23e arranged to allow the free end 23d to pivot relative to the rest of the transmission member 23. This flexible part can be a flexure (for example a neck or a flexible blade allowing articulation in the plane of the member 23), or a hinge associated with a elastic element of ad hoc return.

In order to allow the finger 25 to pass without hindrance when the inertial mass 3 rotates in the clockwise direction, a second flexible part 23f is provided and allows the part intended to cooperate with the finger 25 to retract into the plane of the transmission member 23 following the passage of the finger 25 in said direction of rotation. In this variant, the control cam 19 is a constant radius cam, the shape of the teeth of the locking wheel 13 as well as the shape of the fork 15 being arranged so as to allow a tooth of the locking wheel 13 to escape. following one rotation out of two of the control mobile 16. Of course, the same form of cam 19 as illustrated in the figures 1 to 3 can also be used.

The figure 5 illustrates another variant which varies from that of figures 1 to 3 as following. First, the control cam has six tips, and is shaped like a Star of David. The fork 15 again comprises a single cam sensor 15c which is maintained in contact with the cam 19 by means of a return force exerted by an elastic return element 15d.

Second, the display device 31 is not driven by the finishing gear train, which is dedicated exclusively to driving the impulse wheel. On the other hand, the display 31 is driven by means of a secondary gear train 37, which comprises a secondary energy source 39, such as a barrel, as well as a blocking mobile 41 driven by said energy source. secondary. In the illustrated variant, the blocking mobile comprises two fingers 41a, which are blocked and released by a blocking lever 43 which controls the release of energy from the secondary energy source in order to drive the display 31. The latter is subjected to a restoring force provided by an ad hoc elastic element 43a (or any element known to perform a return function), which serves to keep the lever in contact with a stop 43b, and which exerts sufficient force to lock the mobile locking device 41. However, said return force has been adapted so that said lever 43 can be lifted by means of an element integral in rotation with the inertial mass 3. In the variant illustrated, this element is a pin 45 carried by the rim of the inertial mass 3, but may alternatively be the impulse paddle 9, the finger 25, or any other suitable member.

One end 43c of the locking lever 43 is shaped to interact with the pin 45, and in the illustrated variant, it is curved and takes place in the path of the pin 45 so that, at each alternation of the inertial mass 3, the lever 43 is rotated and releases a finger 41a of the locking mobile 41. The elastic return element 43a ensures that the lever 43 returns to its position against the stop 43b before the next finger 41a comes into contact with the latter to again block the blocking mobile 41.

In doing so, the two energy sources 7, 39 as well as the cogs 8, 37 can be optimized for their respective roles. It should be noted in particular that the elements of the secondary gear 37 can have a significantly reduced size compared to a conventional finishing gear, as mentioned above in the context of figures 1 to 3 .

The figure 6 further illustrates a variant of a system 1 according to the first aspect of the invention, which is based on that of figures 1 to 3 . This variant differs mainly in that the display device 31 is driven by a wheel 47 driven by a retractable finger 23g carried by the transmission member 23. This finger is arranged to drive the wheel 47 at the rate of one step in clockwise on each oscillation of the inertial mass 3, when the finger 25 pushes the transmission member 23 to the left. The wheel 47 is of course positioned by means of a jumper, a friction or the like (not shown).

The shape of the control cam 19 can be chosen according to the needs of the manufacturer, for example by using one of the shapes mentioned above.

The figure 15 further illustrates a variant of a system 1 according to the first aspect of the invention. In this variant, the display 31 is driven by its own energy source 39, as is the case in the variant of the figure 5 . In this variant, this drive is controlled by means of a trigger system 111. The trigger lever 113 is actuated by means of a plurality of elements 45 (such as for example pins, fingers, or teeth) that comprises the control wheel 16. In doing so, each time the latter is actuated, the detent lever 113 is lifted which releases the detent wheel 115 at a rate of one step, which subsequently causes the display 31. Alternatively, the detent lever 113 can be arranged to be controlled by the teeth of the control wheel 21, or by an element carried by the transmission member 23.

The figures 7 , 8a and 8b illustrate an embodiment of a system 1 which is again based on that of figures 1 to 3 which is not only according to the first aspect of the invention, but is also according to a second aspect not forming part of the present invention.

The control cam 19 is formed by a stack of two sub-cams 17a, 17b (see figures 8a and 8b ) coaxial and each having a different number of points. In the illustrated embodiment, the lower sub-cam 17a has three points, and will therefore control the triggering of a pulse one oscillation out of two of the inertial mass as is the case in the figures 1 to 3 . The upper sub-cam 17b has six points, which will therefore trigger a pulse on each oscillation of the inertial mass 3. By choosing the desired sub-cam, the pulse rate given to the inertial mass 3 can be determined. . It should also be noted that it is possible to provide more than two sub-cams.

The single cam sensor 15c is movable vertically, that is to say parallel to the axis of the cams 17a, 17b, thanks to a flexible part 15f that comprises the fork 15. This flexible part 15f is adapted to give sufficient rigidity in the plane of the fork 15 so that the latter functions correctly as regards the blocking and the release of the impulse wheel 5, but exhibits a lower rigidity in the direction perpendicular to said plane. In doing so, the probe 15c can come into contact with one or other of the sub-cams 17a, 17b, and can thus take information on one or the other of the latter. The flexible part 15f can for example be formed by a flexible blade perpendicular to the plane of the fork 15, and can also be arranged so that, in an unstressed state, the cam sensor 15c is in contact with one or the other. other of the sub-cams 17a, 17b, as shown in the figure 8a , which shows the probe 15c in contact with the lower sub-cam 17a when the flexible part 15f is at rest and is not constrained.

In order to select the sub-cam 17a, 17b with which the probe 15c is in contact, actuating means 49 are provided. In the variant illustrated, these means 49 are a flexible fork which includes the part located between the flexible part 15f and the cam sensor 15c.

The actuating means 49 can be moved along an axis substantially parallel to the axis of the sub-cams 17a and 17b following a manual action on the part of the user, or automatically under the control of a function of the watch movement. in which the system is integrated, which will make it possible to move the cam sensor 15c in the direction of the upper sub-cam 17a, in the situations where this proves to be possible (see below).

In the arrangement illustrated, the shape of the two cams has been chosen to allow the probe 15c to rise from the lower sub-cam 17a towards the upper sub-cam 17b, at the places where the radii of the two sub-cams are substantially identical. This situation arises by arranging the spokes of the two sub-cams 17a, 17b in an identical manner at the mid-points located midway between the points of each cam, three of these mid-points of the upper sub-cam 17b with six points being superimposed on the midpoints of the lower three-pointed sub-cam 17a. These coincident midpoints consequently form transition positions, where the probe 15c can move up or down without causing the fork 15 to pivot in its plane, and therefore without triggering a pulse. It goes without saying that other forms of cams which meet these needs are also possible.

The figure 8b illustrates the situation after such a transition, the probe 15c being in contact with the upper sub-cam 17b. The flexible part 15f of the fork is flexed, and depending on the arrangement of the actuating means 49, the distal part of the fork can move parallel (as illustrated), or can tilt.

Regarding a transition from the lower six-pointed cam 17a to the upper three-pointed cam 17b, the illustrated shape of the cams only allows a transition at the transition positions since the tips of the upper cam 17b do not overlap. not at the tips of the upper cam 15a blocks a transition to any other orientation of the sub-cams 17a, 17b. However, this is not the case during a transition in the other direction.

Without providing any safety means, when the cam sensor 15c is on a point of the upper sub-cam 17b which coincides with an intermediate point of the lower sub-cam 17a, a movement of the actuating means 49 downwards will initiate an angular displacement of the fork 15 in its plane, and release the impulse wheel untimely. If this unwanted pulse occurs at a time when the pulse paddle 9 is in the wrong orientation to receive a pulse, a pulse will be triggered and lost, which is detrimental to efficiency and to the power reserve, or worse again, a tooth of the impulse wheel 5 could strike the impulse vane 9 when the latter moves in the wrong direction. The latter situation would risk stopping the oscillations of the inertial mass 3, and / or damaging the impulse wheel 5 and / or the impulse vane 9.

In order to prevent this situation, a security system 51 is provided. The latter consists of a safety wheel 53 comprising a plurality of notches 53a aligned with the aforementioned transition positions, as well as a plurality of lugs 53b interposed between the notches 53a. This safety wheel 53 cooperates with a safety finger 55 integral with the cam sensor 15c.

In doing so, the transition of the cam probe 15c cannot take place outside the transition positions, and the actuating means 49 have adequate elasticity so as not to exert too much force on the safety wheel 53 if a transition is controlled when the control mobile 16 is not in a transition position.

The actuating means 49 can be controlled manually, for example by being in kinematic connection with an operating member such as a push button, a lever or the like located outside the watch case, or can be controlled automatically. . For example, the actuating means 49 could be controlled from a control system of a chronograph, in order to increase the rate of pulses transmitted to the inertial mass 3 when the chronograph is started. In doing so, it is possible to avoid the reduction in the amplitude of the inertial mass 3 which typically occurs when the chronograph is engaged and increases the torque load which the finishing gear 8 must provide.

The figure 9 illustrates another variant of the control mobile 16 which makes it possible to vary the pulse rate. Only the command mobile 16 as well as the elements interacting directly with the latter are shown, the other components of the system being according to one of the variants of figures 1 to 6 .

In this variant, the control wheel 21 is provided with a sun wheel 57 which acts as the first input of a differential planetary gear, the control cam 19 of which is integral in rotation with a sun gear 61 acting as an output. The planetary gear also comprises a planet carrier 59 acting as a second input, which is mounted idle on the axis connecting the sun gear 61 and the control cam 19. The planet carrier 59 carries at least one set of planet gears. 63 integral in rotation with one another, and one of which meshes with the sun wheel 57, respectively with the sun gear 61 in a known manner.

The planet carrier 59 can be locked or released in rotation by actuating means 49, shown schematically by arrows. In this embodiment, these means 49 can be for example a clamp, a locking lever the end of which penetrates into an external toothing which the planet carrier 59 comprises, or any other suitable means.

When the planet carrier 59 is free, it is kinematically linked to the sun gear 57 by means of a limited torque clutch 65 such as a pawl which it carries and which cooperates with the teeth of the sun wheel 57. Alternatively, a friction connection 66 can be provided instead of a pawl 65 (see figure 10 ). In this state, when the control wheel 21 rotates, the planet carrier 59 as well as the sun gear 61 are integral in rotation with the latter. Therefore, the transmission ratio between the drive wheel 21 and the drive cam 19 is 1: 1.

On the other hand, when the planet carrier 59 is locked in rotation by the actuating means 49, the retention force supplied by the pawl 65 (or by the friction) is overcome, and the planet gears 63 pivot and transmit the rotation between the sun gear 57 and the sun gear 61, the gear ratio of the assembly defining the speed ratio between the control wheel 21 and the control cam 19. In the illustrated variant, the sun gear 61 (the output) has fewer teeth than the sun wheel 57 (the input), in particular half of the latter, and therefore the angular speed of the control cam 19 is twice that of the control wheel 21. If the control cam 19 has three points, it has the same effect as the six point cam of the figure 7 when the planet carrier 59 is blocked, which has the effect of doubling the pulse rate compared to the case where the planet carrier 59 is free.

Consequently, the actuation rate of the fork 15, and thus that of the pulses, can be varied by locking or unlocking the planet carrier 59.

It goes without saying that other forms and arrangements of planetary gear are also within the reach of those skilled in the art, and that the angular speed ratios can be modified at will. For example, the rotational speed of the cam can be reduced instead of being increased when the second input is blocked.

The figure 10 represents a variant of the mechanism of figure 9 , in which the limited torque clutch 65 is a friction washer 66 disposed between the planet carrier 59 and the sun gear 57 which serves to link these two components in rotation when the planet carrier 59 is free. By elsewhere, the control cam 19 is no longer integral in rotation with the output 61 of the planetary gear, but is mounted on another wheel 67 which meshes with a pinion 69 which is integral in rotation with said output 61.

In each of the variants of figures 9 and 10 , the gear ratio between the control cam 19 and the control wheel 21 is chosen so that the input of pulses remains synchronous with the oscillations of the inertial mass 3.

The figure 11 illustrates a variant based on that of figure 6 , which allows the pulse rate to be varied independently.

In the illustrated variant, the inertial mass 3 comprises an actuating element 71, which is represented by a pin 71 integral with the rim of the inertial mass 3. Alternatively, this actuating element 71 can be carried by a solid board in rotation of the inertial mass 3, or its functionality can simply be taken up by the finger 25.

This actuating element 71 cooperates with a release lever 73, as described below. The latter is pivotally mounted on a frame member about a pivot point indicated by 73a, and the guide system 29 of the transmission member 23 is arranged to allow lifting of its end which interacts with the wheel. command 21.

When the release lever 73 is at rest (not shown), it does not interact with the transmission member 23, which thus operates as described in figure 6 to drive the mobile control 16 in rotation.

• lorsque l'amplitude d'oscillation de la masse inertielle 3 se trouve en dessous d'un seuil prédéterminé, l'élément d'actionnement 71 n'interagit pas avec le levier de débrayage. À chaque oscillation, le doigt 25 actionne l'organe de transmission 23, qui coopère avec la roue de commande 21 comme décrit ci-dessus.
• lorsque l'amplitude d'oscillation de la masse inertielle 3 excède ledit seuil prédéterminé, l'élément d'actionnement 71 entre en contact avec le levier de débrayage 73 juste après que le doigt 25 ait actionné l'organe de transmission 23, mais avant que ce dernier ait fait pivoter la roue de commande 21 d'un pas. Le levier de débrayage 73 soulève ainsi l'extrémité de l'organe de transmission 23, ce qui l'empêche de faire pivoter la roue de commande 21. La prochaine impulsion est ainsi annulée.

The position of the actuating element 71 on the inertial mass and the geometry of the release lever 73 are chosen such that:

• when the oscillation amplitude of the inertial mass 3 is below a predetermined threshold, the actuating element 71 does not interact with the clutch lever. At each oscillation, the finger 25 actuates the transmission member 23, which cooperates with the control wheel 21 as described above.
• when the amplitude of oscillation of the inertial mass 3 exceeds said predetermined threshold, the actuating element 71 comes into contact with the disengaging lever 73 just after the finger 25 has actuated the transmission member 23, but before that the latter has pivoted the control wheel 21 by one step. The clutch lever 73 thus lifts the end of the transmission member 23, which prevents it from rotating the control wheel 21. The next pulse is thus canceled.

This arrangement effectively allows for negative feedback control over the amplitude of oscillation of the inertial mass. By arranging the system to provide a pulse rate that is too high to maintain the desired amplitude of oscillation, the interaction between the actuator 71 and the release lever 73 cancels the input of pulses to the inertial mass 3 when the amplitude is greater than the predetermined threshold. In doing so, the amplitude of the inertial mass 3 decreases until the moment when its amplitude becomes less than that defined by said threshold. At this time, the actuating element 71 no longer cooperates with the disengaging lever 73, and the pulses start again until the moment when the oscillation amplitude again exceeds said threshold, at which time the pulses are at again canceled.

The amplitude of the inertial mass 3 is thus maintained in a relatively narrow range, and this independently of the torque supplied by the finishing gear 8, this torque varying due to the engagement or release of additional mechanisms such as control mechanisms. chronograph. The system is thus self-regulating.

On the other hand, it should be noted that the rotation of the finishing gear train is no longer synchronous with the oscillations of the inertial mass, and that consequently the display 31 is driven by the wheel 47 driven by a retractable finger 23g carried by the transmission member 23, as is the case in the figure 6 . The shape of the teeth of wheel 47 is chosen such that the latter is driven regardless of whether the transmission member 23 is in the “normal” position or in the “disengaged” position. It should also be noted that other possibilities exist for the training of the display 31, and therefore As such, we can mention a gear train dedicated to this training and having its own motor source or its own power take-off on the barrel which is triggered by the movements of the transmission member 23 or of the inertial mass 3. We can imagine this is a trigger system in which the trigger is raised each time the transmission member 23 is actuated (as is the case in the variant of the figure 15 ), or by an ad hoc body which is driven by the inertial mass 3.

The figure 12 illustrates yet another embodiment according to a second aspect not forming part of the invention.

In this embodiment, the input of the pulses is delocalized from the finishing gear 8. The latter extends from the energy source 7 to a detent wheel 75, which is blocked by a detent lever 77, which has been shown schematically but which can take a conventional form ensuring that, on each actuation of the lever 77, the detent wheel advances at the rate of one pitch of its toothing under the control of an ad hoc member 79 integral in rotation with the inertial mass 3. This member 79 has been represented by a pin fixed to the rim of the inertial mass, but can be a conventional pallet carried by a board. In the illustrated variant, said pin 79 cooperates with a curved part of the trigger lever 77 in order to actuate the latter at a rate of once per alternation of the inertial mass. Other arrangements actuating the detent lever 77 once by alternation or by oscillation are of course possible.

The pulses are supplied to the inertial mass 3 by means of an impulse wheel 5 which is separate from the detent wheel 75 and which cooperates with an impulse paddle 9 carried by a plate integral in rotation with the mass inertial 3. The impulse wheel 5 has its own power take-off 85 on the power source 7, which enables the impulse wheel 5 to take force independently of the finishing gear 8. In doing so, a differential gear can be arranged in the cog in order to divide the torque coming from a single barrel and going on the one hand to the cog of finishing 8 and on the other hand to the impulse wheel 5, as is already well known in the context of movements comprising two (or even more) regulating systems. Alternatively, the impulse wheel 5 can be driven by its own dedicated energy source.

The fork 15 locks and releases the locking wheel 13 in the manner described above, and is controlled by an appropriately shaped control cam 19, which pivots about its axis and controls the lever 15 to release the impulse wheel. at the rate of one tooth per actuation. Those skilled in the art know how to arrange the cam, the lever, and the shape of the impulse wheel to achieve this goal, as described above.

The control cam 19 is rotated from a power take-off 81 on the finishing gear 8. In doing so, the rotation of the control cam 19 and consequently the supply of the pulses is synchronized with the oscillations of the inertial mass. 3 by means of the trigger 77 and its releases from the trigger wheel.

In order to vary the rate of the pulses, a “gearbox” type gear 83 is interposed in the kinematic chain connecting the control cam 19 to the power take-off 81. This gearbox has been shown schematically, but can for example be a planetary gear of the same type as shown in the figures 9 and 10 , a stack or chaining of several such gears in order to provide more than two speeds of rotation of the control cam 19, or alternatively a gearbox gear of the type known in the context of bicycle transmissions (see for example the documents US3021728 , US2301852 , US832442 and others) or any other suitable arrangement. The number of speeds can be chosen according to the needs of the manufacturer.

In order to modify the speed of rotation of the output of the gearbox 83, an actuating means 49 acts on the latter in order to select the speed of rotation of the output, and therefore that of the control cam 19. If the gearbox corresponds to the planetary gear of the figures 9 and 10 , the actuating means 49 may be as mentioned above in the context of the corresponding figures.

The rate of the pulses can thus be modified, the speed ratios supplied by the gearbox 83 being chosen so as to maintain the synchronization between the impulse wheel 5 and the oscillations of the inertial mass 3. For example, one could choose the speed ratios to obtain an impulse by oscillation, an impulse by two oscillations, one by three, one by four, ..., or any combination of two or more of these possibilities according to the needs of the manufacturer.

In this variant, the finishing gear 8 advances at a constant rate and can therefore drive a display device 31 in a conventional manner.

The embodiment of the figure 13 is based on that of the figure 12 , and differs from the latter in that the control of the gearbox 83 is performed automatically.

In this variant, the default state of the gearbox 83 is chosen so as to supply pulses to the inertial mass 3 at a rate tending to make the latter oscillate with an amplitude greater than a predetermined threshold.

When the amplitude of the inertial mass 3 exceeds this threshold (which can be for example 330 °, 300 °, 280 ° or any other value less than 360 °, preferably less than 340 °), an element of actuation 71 (such as a pin or a finger integral in rotation with the inertial mass) cooperates towards the end of an oscillation with a engagement lever 87 which is, in the illustrated variant, a clutch lever in desmodromic connection with the actuating means 49 of the gearbox 83 on the one hand (for example by means of one or more levers), and on the other hand which serves to engage a clutch 89 making it possible to kinematically link a cam holding 91 with the finishing gear 8. By default, part of the actuating means 49 is kept in contact with the surface of the holding cam 91 by the intervention of an ad hoc elastic element. When this cam 91 is at rest, the actuating means 49 are in contact with the bottom of a notch 93 which is arranged to activate the actuating means 49 when the cam 91 pivots.

Therefore, when the actuating element cooperates with the engagement lever 87, the latter is rotated counterclockwise, which acts on the actuating means 49 to change the state of the gearbox 83 and thereby reducing the pulse rate to a level which is insufficient to maintain the desired oscillation amplitude. At the same time, the clutch 89 is engaged, and the locking cam 91 begins to rotate clockwise under the control of the finishing gear 8. The shape of the notch as well as the cylindrical circumference of the retaining cam 91 makes it possible to retain the actuating means 49 in the activated state, which also maintains the clutch in the engaged state thanks to the desmodromic connection between these elements.

The holding cam subsequently performs a full revolution, during which the pulse rate is reduced, this reduced rate being chosen such that the amplitude of oscillations of the inertial mass 3 decreases below said predetermined threshold.

At the end of the cycle of the locking cam 91, the actuating means 49 fall back into the notch 93 under the effect of the ad hoc elastic element, which returns the gearbox to its previous state, and disengages again the clutch 89. The output speed of the gearbox 83 therefore increases the rate of pulses supplied to the inertial mass 3, which begins to increase the amplitude of the latter until the moment when the actuating element 71 again cooperates with the engagement lever 87.

If, on the other hand, the amplitude remains too great, at the end of the cycle of the locking cam 91, the engagement lever 87 will be actuated again, and a new cycle begins again.

The amplitude of the inertial mass is thus maintained within a relatively narrow range, and this independently of the torque supplied by the finishing gear 8 and its variations due to engagement or disengagement. additional mechanisms such as chronograph mechanisms. The system is thus self-regulating.

The figure 14 further illustrates an embodiment according to the second aspect which does not form part of the invention. In this variant, the maintenance system 1 may for example be according to the embodiment of one of the figures 7 to 10 or 12 , and the actuating means 49 are controlled automatically by means of a rest detector 95. This detector 95 is designed to determine whether the user is no longer wearing his watch which contains the maintenance system 1 according to this aspect, and controls the servicing system 1 such that the pulse rate is reduced, i.e. the system is in a mode in which fewer pulses are supplied to the inertial mass 3. This doing so, the power reserve of the part can be increased since the mainspring 7 takes place less quickly.

For this purpose, the detector comprises an oscillating mass 97 arranged to wind up an auxiliary barrel 99 of conventional shape which houses a mainspring 99a in a known manner. This oscillating weight can also be used to wind the motor source 7 in a known manner, as represented by the dashed line. However, the oscillating mass 97 can be dedicated to the detector 95.

The drum of the barrel 99 rotates a regulating device 105, allowing the mainspring 99a of the auxiliary barrel 99 to unwind at an appropriate speed, for example in five minutes, in 10 minutes, or according to another period chosen by the manufacturer. and which ensures that the barrel does not unwind faster than it is fed by the oscillating mass 97. The illustrated adjustment device comprises a paddle wheel 107 which is in kinematic connection with the drum of the barrel 99 and which rotates in a chamber 109 filled with a viscous fluid such as oil, gelatin or the like. It is also possible to use a flywheel, a paddle wheel which rotates in air or another gas, or even a sprung balance which cooperates with an escapement. It is of course possible that the auxiliary barrel 99 is wound up by its drum and unwinds by its shaft, as is generally known.

The auxiliary barrel 99 is associated with a power reserve system 101 of any kind. In the illustrated variant, the power reserve system is based on a differential gear, one of the inputs 101a of which is in kinematic connection with the drum of the auxiliary barrel 99, and thus pivots when the motor spring (not illustrated) located at the interior of the auxiliary barrel 99 unwinds. The second entry 101b meshes with a wheel integral with the inner end of the mainspring, and therefore pivots when the mainspring is wound up under the effect of the oscillating mass 97. Those skilled in the art are already familiar with various forms of oscillating masses 97. and automatic winding systems which connect mass 97 to the mainspring in order to wind it, and it is therefore not necessary to describe this aspect of the system in more detail.

The output 101c of the differential gear 101 drives a mobile 103 (also shown in a plan on the left of the figure 14 ) whose angular position corresponds to the state of winding of the motor spring of the auxiliary barrel 99. In order to control the actuating means 49, this mobile 103 carries a cam, a finger or the like 103a arranged to control the actuating means 49 when the winding state of said barrel 99 is below a predetermined threshold. At this given moment, the actuating means 49 act on the pulse rate control system, in order to select an operating mode in which the pulses are supplied at a reduced rate (lower rate) than the inertial mass 3. In the context of the embodiment of figures 7 to 8b , the sub-cam 17a having a lower number of points is thus palpated by the feeler 15c, in that of the figures 9, 10 and 12 , the control cam 19 pivots at its lower speed.

Assuming that the watch has been put on for a sufficient period of time to fully unwind the barrel 99, the cam 103a controls the actuating means 49 to select the lower rate of the maintenance system 1. When the user begins to wear his watch, the movements of the wearer's arm cause movements of the oscillating mass 97, which winds up the mainspring of the auxiliary barrel 99 more quickly than it unwinds by driving the regulating device 105. The mobile 103 thus pivots, and the cam 103a controls them. actuating means 49 for selecting a higher pulse rate of the maintenance system 1. The inertial mass 3 thus receives more pulses.

When the user takes off his watch and places it on a surface, the oscillating mass 97 stops oscillating, and the auxiliary barrel 99 is no longer powered. The latter unwinds by driving the regulation device 105, and the mobile 103 pivots so that the cam 103a cooperates with the actuating means 49 so that the maintenance system is put back into a mode ensuring the supply. pulses at the lower rate.

As part of the variant of the figure 14 , one can alternatively use a power reserve device 101 based on elements cooperating by screwing, as for example disclosed in the documents EP2869137 , CH330559 , CH337786 and others.

Although the invention has been described above in connection with specific embodiments, additional variants are also conceivable without departing from the scope of the invention as defined by the claims. Furthermore, the various embodiments can be combined according to the set of modalities making technical sense.

Claims (6)

1. Sustaining system (1) for a timepiece oscillator comprising an inertial mass (3) arranged to oscillate under the effect of a return force supplied by an elastic element, said system (1) comprising:

   - an impulse wheel (5) intended to be kinematically connected to an energy source (7) and arranged to supply impulses to said inertial mass (3) in order to sustain the oscillation thereof;

   - a blocking member (15) arranged to sequentially block and release said impulse wheel (5);

   characterized in that said system (1) also comprises

   - a control mobile (16) arranged to command said blocking member (15) to block and release said impulse wheel (5) in synchronism with the oscillations of said inertial mass (3); and

   - a transmission member (23) arranged to drive said control mobile (16) in rotation at a rate of one step per oscillation of said inertial mass (3).
2. System (1) according to the preceding claim, wherein said control mobile (16) comprises at least one control cam (19) which cooperates with said impulse wheel (5).
3. System (1) according to the preceding claim, wherein said control cam (19) cooperates with said impulse wheel (5) via a lever (12) comprising a feeler-spindle (15b) arranged to cooperate with said cam (19), and at least one blocking element arranged to block and to release said impulse wheel (55) under the control of said cam (19).
4. System (1) according to one of the preceding claims, wherein said transmission member (23) is a lever or a beam arranged to cooperate with said control mobile (16) and with said inertial mass (3).
5. System (1) according to one of the preceding claims, wherein a display (31; 33) is arranged to be driven and/or controlled by said transmission member (23) or by said control mobile (16).
6. System (1) according to one of Claims 1 to 4, wherein a display (31; 33) is arranged to be driven by an energy source (39) under the control of an element (23g; 45) carried by said transmission member (23), or by said control mobile (16) or by said inertial mass (3).

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