EP3176652B1 - Movement for a timepiece and timepiece comprising such a movement - Google Patents

Description

TECHNICAL AREA

The present invention relates to a clockwork movement comprising a power source supplying components forming two distinct kinematic chains, each kinematic chain comprising a regulating system, the frequency of rotation of said control systems being different from each other.

It also relates to a timepiece in which such a movement is mounted.

PRIOR ART

Mechanical watches having regulating systems such as vortices or carousels have been known for a long time. The objective of integrating such a regulating system into a watch is to improve the isochronism of the balance, this isochronism can be faulted because of the different effect of the gravity depending on the position of the pendulum and the fact movements of the wearer of the watch and the position of this watch. A regulating system such as for example a vortex has the effect of moving the pendulum by making it rotate for a defined time, usually one minute. When the watch is in a vertical position, the balance thus takes all possible vertical positions during a revolution.

Many solutions based on the use of swirls or carousels have been proposed to further improve the isochronism of the balance. Among these solutions, some advocate the use of two or even three vortices. In all cases, these different vortices have an identical rotation speed or at least very close. The purpose of using several eddies or more generally several control systems is to make an average of the corrections of each system. The average of the corrections being more stable than the individual correction of each system, the isochronism is improved.

The control systems of watch movements comprising several vortices can be kinematically related to each other or not. In particular, there exist so-called resonance vortex systems comprising three identical vortices. These eddies have by construction, a rotation frequency close to one another. The frequency of rotation of each of them adapts to the frequency of other vortices by a phenomenon of resonance. Thus, the rotation frequency of each of the vortices tends towards the average of the rotation frequency, without the vortices being linked "mechanically" between them.

As recalled above, vortices are provided to move the exhaust in all possible positions in a plane, during a revolution. These eddies or more generally these control systems work perfectly well when the watch is in the vertical position and the movements of the wearer of the watch are relatively slow. These regulating systems have also been developed originally for pocket watches.

The majority of current watches with regulating systems are not pocket watches, but wristwatches worn on the wrist of a user. As a result, these watches undergo much more varied movements and having speeds, accelerations and amplitudes of movement much larger than pocket watches.

Depending on the movements of the wearer of the watch, the correction of the isochronism can be more or less effective. In particular, the range of movements (speed, acceleration, amplitude) at which a regulating system is sensitive is limited according to the frequency of rotation of this regulating system. As a result, the efficiency of the control systems of current watches is not necessarily optimal, depending on the movements of the wearer of the watch.

When multiple vortices are used at similar rotational speeds, these vortices have a substantially fixed relative position. As a result, the effect of gravity on vortices is the same as if there was only one regulating system. From the technical point of view, the only advantage of having two control systems, in the movements of the prior art, is to have a more stable average of corrections than an individual correction.

Among watch movements with more than one regulating system, some require a large amount of energy to maintain the movement. In order to provide a sufficient power reserve, some movements incorporate up to four barrels. This requires a large volume, which imposes aesthetic constraints on the watch.

It can thus be seen that, due to the synchronous movement of vortices, the correction of isochronism is not fundamentally improved by the addition of vortices. On the other hand, the consumption of energy is increased. This requires a larger box volume and thus limits the achievements to watches of large diameter and / or thick.

Moreover, the setting of several vortices is an extremely delicate operation. It is therefore advantageous that this adjustment can be done as conveniently as possible, to enable an operational movement in reality.

The document CH 700 459 describes a timepiece comprising two resonators. This timepiece comprises a first wheel resulting in a first resonator and a second wheel driving a second resonator. According to one embodiment, these two resonators can move at different frequencies from each other. The first and second wheels are driven by a single source of energy.

In this invention, each of the resonators acts on a different set of indicators. One of the resonators concerns only the chronograph. The other resonator relates only to the time display.

The purpose of the invention described in CH 700 459 is to separate the resonators according to the function they perform.

The patent application CH 708 373 relates to a clockwork movement comprising two energy sources, each energy source forming part of a kinematic chain terminating in a regulating member. These two kinematic chains are interconnected by a coupling means.

Due to the presence of the coupling means, the regulating members have a similar frequency and interact with each other so as to synchronize their frequency.

SUMMARY OF THE INVENTION

The present invention proposes to overcome the drawbacks of the systems of the prior art by proposing a clockwork movement allowing a good maintenance of the isochronism of the balance and therefore a good accuracy of the watch. The movement according to the invention is also able to take into account a wide range of movements, speeds or accelerations of the watch. Therefore, the corrections offered by the control systems apply to a wide range of movements of the wearer of the watch.

The movement of the invention proposes to operate with a single barrel while providing a power reserve compatible with use in real life. This makes it possible to integrate the movement into a housing "conventional" dimensions. The movement according to the invention is furthermore designed so as to allow easy adjustment.

The objects of the invention are achieved by a watch movement as defined in the preamble and characterized in that each kinematic chain comprises a torque stabilizer disposed between the power source and the regulating system.

The object of the invention is also achieved by a timepiece comprising the movement described above.

In the timepiece movement according to the present invention, several control systems are provided. These control systems are kinematically related to each other. However, unlike known movements, each regulating system has a different speed or a different frequency of rotation. In this way, the ranges of motion to which each of the control systems is sensitive are different. Thus, the corrections of the isochronism apply on a large range of movements of the wearer of the watch.

According to an advantageous embodiment of the timepiece movement according to the present invention, one of the control systems has a rotation frequency greater than the conventional rotation frequency of this kind of control systems, which is one turn per minute. A higher rotation frequency ensures that the exhaust takes different positions after a short time. This ensures a better stability of the isochronism and thus a better precision. In addition, the relative position of the escapements of the control systems also changes rapidly, unlike the movements of the prior art in which the movements of the escapements are synchronous. In conventional movements, a high rotational speed requires the input of a large amount of energy. For this reason, there are very few control systems with rotational frequencies greater than one revolution per minute. In practice, the vortices having the highest rotation frequency have a rotation frequency of three revolutions per minute. No The regulating system has a rotation frequency close to, equal to or greater than 10 revolutions per minute, as in the case of the present invention.

As is well known, a whirlwind is considered one of the most difficult complications to achieve and settle. Having two swirls increases the difficulty of the setting. The fact of having two vortices rotating at different rotational frequencies and distant from each other gives rise to particularly great adjustment difficulties. It should be noted that in practice, it is not possible to make such a functional clockwork movement without having to make an adjustment. For this reason, the simplification of the adjustment plays a significant role in the realization of a movement that is able to function in practice.

The present invention proposes to make a movement for a timepiece comprising two control systems, one of which rotates at a frequency much higher than the other and greater than one revolution per minute. This movement has a power reserve compatible with a concrete practical realization while keeping a conventional volume. Movement can be adjusted to ensure proper long-term operation under real-life conditions. The result is an increased accuracy compared to the mechanical movements comprising one or more control systems, this movement being able to take into account a wide range of movements of the wearer of the watch.

SUMMARY DESCRIPTION OF THE DRAWINGS

• la figure 1 est une vue schématique d'une partie du mouvement selon la présente invention;
• la figure 2 est une vue de face des composants d'une première chaîne cinématique du mouvement selon la présente invention;
• la figure 3 est une vue de profil des composants de la chaîne cinématique illustrée par la figure 2;
• la figure 4 est une vue de face des composants d'une seconde chaîne cinématique du mouvement selon la présente invention;
• la figure 5 est une vue de profil des composants de la chaîne cinématique illustrée par la figure 4;
• la figure 6 représente un stabilisateur de couple tel qu'utilisé dans le mouvement de l'invention, en vue de face; et
• la figure 7 illustre le stabilisateur de couple de la figure 6, en perspective.

The present invention and its advantages will be better understood with reference to the appended figures and to the detailed description of a particular embodiment, in which:

• the figure 1 is a schematic view of a part of the movement according to the present invention;
• the figure 2 is a front view of the components of a first kinematic chain of motion according to the present invention;
• the figure 3 is a profile view of the components of the kinematic chain illustrated by the figure 2 ;
• the figure 4 is a front view of the components of a second kinematic chain of motion according to the present invention;
• the figure 5 is a profile view of the components of the kinematic chain illustrated by the figure 4 ;
• the figure 6 represents a torque stabilizer as used in the movement of the invention, in front view; and
• the figure 7 illustrates the torque stabilizer of the figure 6 , in perspective.

MANNER OF REALIZING THE INVENTION

With reference to the figures, the invention relates to a movement for a timepiece comprising essentially a power source 11, a center mobile 12 and two control systems 13, 14. Conventionally, the movement may comprise other Mobile, particularly a mobile hours with an hour hand 16 and a mobile minute 17 with a minute hand 18. According to an advantageous embodiment, the energy source takes the form of a conventional barrel 19. This barrel, or more generally this source of energy 11 engraine with the center mobile 12, this center mobile being part of two kinematic chains 20, 21 different. Each of these kinematic chains results in one of the control systems 13, 14, represented in the form of a vortex.

One of the kinematic chains, here called first kinematic chain 20, is illustrated by the Figures 2 and 3 . In the illustrated embodiment, the regulating system 13 of the first kinematic chain is of the tourbillon type and comprises an escapement 22 with a Swiss anchor, this escapement being formed of an escape wheel 23 and an escape gear 24 This regulating system 13 further comprises an anchor 25 and a sprung balance 26 cooperating with the anchor 25 so as to adjust its displacement. The anchor and the exhaust are mounted on a pivoting cage 27 integral and coaxial with a mobile which can be a wheel of seconds. As in a conventional vortex, according to an advantageous embodiment, the exhaust 22 performs a complete rotation in one minute.

The first driveline 20 further comprises a first torque stabilizer 28. Such a torque stabilizer is illustrated in detail by the Figures 6 and 7 . This torque stabilizer is formed of a wheel 29 and a pinion 30. These two elements are capable of pivoting about the same axis 31, the wheel being mounted idly on this axis. The pinion 30 is integral with an inner disk 32 and engrains with the center mobile 12. The inner disk 32 further comprises two pivots 33 whose function is explained below. The inner disk 32 is integral with a spiral spring 34 in charge of transmitting the torque of the pinion 30 to the wheel 29. This spiral spring 34 can be fixed by one of its ends to the inner disk 32, for example by means of one of the pivots 33. The spiral spring 34 is furthermore fixed to the wheel 29 so that the wheel and the inner disk 32 are kinematically connected to one another by means of the spiral spring 34.

The wheel 29 of the first torque stabilizer 28 has a transverse arm 35 disposed substantially along a diameter of this wheel. The pivots 33 of the torque stabilizer are arranged such that they exceed the cross arm 35 in height. In this way, the pivots 33 act as a limiting member of the stroke of the inner disk 32 relative to the wheel 29. This stroke limiting function makes it possible to prevent the breaking of parts, in particular of the spiral spring. 34, in the case of a race too important. The pin limitation function 33 is also useful to prevent the spiral 34 from winding or unrolling completely, its turns are in contact with each other and so it has more elastic properties. The pivots 33 also facilitate the adjustment of the angular displacement of the inner disk 32. In fact, after an ideal setting, the pivots should undergo angular displacement as large as possible, without however resisting against the transverse arm. The adjustment of the movement of the inner disk 32 relative to the wheel 29 can be done initially by selecting a spiral spring 34 adapted. In a second time, this adjustment can be done by means of a movable peg holder if such a peg carrier is provided, or by moving a ferrule in which is fixed the spiral spring 34.

In operation, the barrel 19 produces a torque that it transmits to the center mobile 12. This latter transfers a portion of the torque to the first torque stabilizer 28 via the pinion 30 of this torque stabilizer. The torque stabilizer wheel 29 engages with a center pinion 15 of the first regulating system 13. The first regulating system causes the anchor-exhaust assembly to rotate at a rotation frequency of one revolution per minute through the movable seconds and exhaust pinion 24.

Unlike conventional tourbillon timepieces, the exhaust pinion 24 does not engage rigidly with the center wheel 12. The first torque stabilizer 28 is disposed between the center wheel 12 and the regulating system 13 of the wheel. to produce an elastic connection. As regards the frequency of rotation of the first regulating system, it is advantageously the same as for a conventional clockwork movement, namely of the order of one revolution per minute. The gear ratios are therefore calculated accordingly.

The second kinematic chain 21 is illustrated in detail by the Figures 4 and 5 . This second kinematic chain comprises the center mobile 12 which is also contained in the first kinematic chain 20, a torque stabilizer 36, two intermediate mobiles 37, 38 and the second regulating system 14.

In more detail, the second torque stabilizer 36 is similar to the first torque stabilizer 28. In other words, it is formed of a pinion 39 and a wheel 40, these two elements being coaxial, but not rigidly fixed to each other so as to be pivotable relative to each other on a common axis 41. The pinion 39 and the wheel 40 of the second torque stabilizer are connected by a spiral spring 42 in charge of transmitting a torque of the pinion 39 to the wheel 40 of this stabilizer.

The wheel 40 of the second torque stabilizer 36 engrains with a wheel 43 of the first intermediate wheel 37. The wheel 43 of the first intermediate wheel engages with a pinion 45 of the second intermediate wheel 38 formed of the pinion 45 and a wheel 46. The wheel of this second intermediate mobile engraine with a pinion 47 of the second regulating system 14.

It should be noted that the second torque stabilizer 36 is illustrated in the figures 1 and 4 in a position between the center mobile 12 and the first intermediate mobile 37. This torque stabilizer could be placed in other places of the second kinematic chain, in particular between the two intermediate mobiles or between the second intermediate mobile and the second regulating system.

In the second kinematic chain, the presence of two intermediate wheels results in a gear ratio different from that of the first kinematic chain. In addition, the second regulating system is different from the first regulating system in that its rotation frequency is significantly higher.

In more detail, the second regulating system 14 is formed in particular of the pinion 47, a wheel 48 and a 49 escapement with Swiss anchor. The wheel 48 engrains with a pinion 50 of the escape wheel, named exhaust pinion. The exhaust pinion 50 is larger than the corresponding exhaust pinion 24 of the first regulating system 13. As a corollary, the wheel 48 of the second regulating system 14, called the fixed second wheel 48, is smaller than the fixed second wheel. 48 'corresponding to the first regulating system 13. The respective dimensions of the wheel of the second vortex and the exhaust pinion and the dimensions of the first and second intermediate mobiles are such that the frequency of rotation of the exhaust 49 of the second regulating system is significantly higher than the rotation frequency of the exhaust 22 of the first regulating system.

In the context of this invention, the term "significantly higher" means that, unlike other watch movements comprising more than one vortex, the frequencies are sufficiently different to avoid that they agree by a phenomenon of resonance. This difference in frequency should be at least 20%. According to an advantageous embodiment, the rotation frequency of the second regulating system 14 is at least equal to twice the frequency of the first regulating system 13. According to a specific embodiment, the rotation frequency of the second regulating system is ten turns per minute for the second system setting 14 against one revolution per minute for the first regulating system 13.

Such a rotation frequency of the escapement 49 generates a number of constraints. On the one hand, the moving mass must be as small as possible to minimize energy consumption. For this purpose, materials having a relatively low density are advantageously used for the manufacture of the control system. On the other hand, the parts must withstand mechanical constraints totally unconventional for this kind of parts. The materials used must fulfill these constraints. These materials may in particular comprise titanium or a titanium alloy. In order to provide enough energy, the barrel 19 can also be optimized, in particular at the level of the spring used.

Another significant element is the fact that the two torque stabilizers 28, 36 engraining with the center wheel 12 are placed on separate axes of rotation 31, 41. This allows adjustment of each of the torque stabilizers independently. This is important for a concrete realization, knowing that the realization of a regulating system of tourbillon type is particularly complex and that the setting of two vortices rotating at different speeds is all the more difficult. It is therefore important to be able to access the settings of the elements that are part of the kinematic chains.

The fact of having a torque stabilizer in each driveline allows a good running and a good regulation of the movement. Indeed, the spirals of the torque stabilizers have an effect that compensate each other so as to regulate the movement. The presence of pivots 33 on the torque stabilizers makes it possible to prevent the springs 34, 42 from loading or discharge beyond a certain limit and thus ensures that the amplitude of the displacement of the internal disk of the torque stabilizers remains within an operating range of the system.

The movement according to the present invention has been described with control systems made in the form of vortices. At least one of these could be replaced by other control systems such as a carousel.

Claims (14)

1. A clockwork movement including a power supply (11) feeding components forming two distinct kinematic chains (20, 21), each kinematic chain comprising a regulating system (13, 14), the frequency of rotation of said regulating systems being different from each other, characterized in that each kinematic chain comprises a torque stabilizer (28, 36) arranged between the power supply (11) and the regulating system (13, 14).
2. The clockwork movement according to claim 1, characterized in that the frequency of rotation of one of the regulating systems (14) is higher than the frequency of rotation of the other regulating system (13) by at least 20%.
3. The clockwork movement according to claim 1, characterized in that the frequency of rotation of one of the regulating systems (14) is at least equal to twice the frequency of rotation of the other regulating system (13).
4. The clockwork movement according to claim 1, characterized in that the frequency of rotation of one of the regulating systems (14) is at least equal to 10 times the frequency of rotation of the other regulating system (13).
5. The clockwork movement according to any of the preceding claims, characterized in that the regulating system (13) having the lowest frequency of rotation has a frequency of rotation equal to one revolution per minute.
6. The clockwork movement according to claim 1, characterized in that the torque stabilizer (28, 36) comprises a wheel (29, 40), an internal disc (32) integral with a pinion (30, 39), the wheel (29, 40) and the internal disc (32) being assembled on a common rotational shaft (31, 41), the wheel (29, 40) being rotatably mounted on the shaft, the pinion (30, 39) being integral with the shaft (31, 41) and in that the wheel and the pinion are connected to each other by a spiral spring (34, 42).
7. The clockwork movement according to claim 6, characterized in that the torque stabilizer (28, 36) comprises at least one limiting member limiting the stroke of the wheel (29, 40) with respect to the internal disc (32).
8. The clockwork movement according to claim 7, characterized in that the stroke limiting member comprises at least one pivot (33) integral with the internal disc (32) and a transversal arm (35) integral with the wheel (29, 40) of the torque stabilizer.
9. The clockwork movement according to claim 1, characterized in that the second kinematic chain (21) comprises at least one intermediate moving part (37, 38) arranged between the power supply (11) and the regulating system (14).
10. The clockwork movement according to claim 9, characterized in that the second kinematic chain (21) comprises at least two intermediate moving parts (37, 38) arranged between the power supply (11) and the regulating system (14), one of the intermediate moving parts (37) being in contact with the torque stabilizer (36) and another intermediate moving part (38) being in contact with the regulating system (14).
11. The clockwork movement according to claim 1, characterized in that each regulating system (13, 14) comprises an escapement (22, 49) provided with a pinion (24, 50), and a second fixed wheel (48, 48') in connection with the escapement pinion (24, 50), and in that the escapement pinion (24) of the first regulating system (13) has a different size from the escapement pinion (50) of the second regulating system (14).
12. The clockwork movement according to claim 1, wherein the regulating system (13, 14) comprises a tourbillon.
13. The clockwork movement according to claim 1, wherein the regulating system comprises a karussel.
14. A timepiece including a clockwork movement according to any of the claims 1 to 13.

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