EP3584641B1 - Automatically starting and secured detent escapement for timepieces - Google Patents

Description

Fields of invention

The present invention relates to a watch escapement of the detent type as well as a watch movement and a timepiece, in particular a mechanical watch, comprising such an escapement. More particularly, the present invention relates to a watch escapement with detent adapted to be integrated into a watch movement and arranged to transmit a torque originating from a source of energy of said watch movement to an oscillating regulator member of said watch movement, the regulator member of the watch movement comprising a first mobile and the escapement comprising a second mobile as well as an escape wheel, said first mobile cooperating with said second mobile while being capable of immobilizing the second mobile in a first or a second position defined respectively by a first and a second stop against which the said second mobile comes to rest, the said escape wheel being arranged so as to transmit, during a half-phase of each oscillation of the regulator member, a torque to said regulator member through a direct impulse.

State of the prior art

The escapement being one of the centerpieces of a watch movement, there are a large number of different types of watch escapements. In general, in the context of mechanical timepieces, there is the family of permanent contact escapements in which the oscillating regulator of the movement, the balance, is constantly in contact with a part of the escapement and the family of free escapements in which the balance has no contact with the escapement except during disengagement and impulse.

The family of free exhausts mentioned last itself includes several types of exhausts. In addition, this family includes the Swiss lever escapement which represents the vast majority of horological escapements currently used in wristwatches having a mechanical movement. Those skilled in the art are fully aware of the components as well as the operation of this type of exhaust which is illustrated diagrammatically in FIG. 1a, which is why the structure, the operation and the corresponding nomenclature will not be repeated at this point. Likewise, those skilled in the art know that a Swiss lever escapement is usually fitted with a part called “dard” g in order to avoid what is known in watchmaking under the name “reversal” of the anchor. c which results in the immediate stopping of the balance, respectively of the corresponding timepiece. Without sting, a reversal of the anchor of such an escapement can occur during certain phases of its operation, namely while the balance wheel traverses its additional arc and the anchor c is positioned against one or the other. limit stops e, for example following an impact which moves the anchor c from its target position and brings it prematurely against the other limit stop e, so that the pin t of the large plate i of the balance wheel will no longer meet the entrance but accidentally encounter the reverse of one of the two horns of the fork f of the anchor c, resulting in the immediate stopping of the balance. The use of a dart g, which is a small metal pin fixed in the stud at the end of the fork f of the lever escapement, avoids this problem because the dart g works with the small one. plate h carried by the axis of the balance j and prevents accidental movements of the fork f during the additional arc of oscillation of the balance. Because of these geometric constraints, a Swiss lever escapement is fairly well secured against shocks and is particularly suitable for use in wristwatches.

The family of free exhausts also includes the so-called detent escapement which is illustrated schematically on figure 1b and which is considered to be the best escapement from a chronometric point of view. The principles of a detent escapement having been known for a long time, they will not be repeated here either, but - in order to facilitate the understanding of the present invention as well as of its context - it is recalled that it is a question of 'a direct-impulse escapement, unlike the Swiss lever escapement mentioned above which belongs to the family of indirect impulse escapements in which the impulse is transmitted from the escape wheel to the balance via the intermediary of the 'anchor. In a detent escapement, in short, the teeth of an escape wheel f rest on a stone called rest a and carried by a spring called detent b, an extension of which is in the field of action of a paddle release c, the latter operating the release of the escape wheel at each oscillation of the balance, so that one tooth of the escape wheel f leaves the rest a and another of its teeth, acting on the pallet impulse e carried by the large plate d, gives impetus to the balance. The impulse is therefore transmitted directly by the escape wheel to the balance, which results in a number of advantages. We also take into account the fact that (a) the escapement disturbs the balance to a lesser extent since there is only one pulse per period of oscillation, compared to the Swiss lever escapement which disturbs the balance. the pendulum twice per period. In other words, the detent escapement has what a person skilled in the art knows under the name "lost blow", that is to say a half-oscillation without impulse. A direct-impulse escapement also has (b) better efficiency because of the direct transmission of the impulse from the escapement wheel to the balance, without passing through an additional component such as the anchor which drives loss of efficiency. In addition, (c) by virtue of the fact that the impulse takes place along a direction which is orthogonal to the line connecting the centers of the escape wheel and the balance as well as to the absence of an impulse transmitted at the level of the anchor, the friction during the impulse as well as the risk of bracing are reduced, which makes it possible to eliminate the need for lubrication. Moreover, (d) the fact that there is a lost blow allows a precise adjustment of the position of the single pulse by oscillation with respect to the neutral point of the oscillator, which is not possible in Swiss anchor having two pulses per period of oscillation, since an adjustment of the positioning of the pulse before or after neutral in one half-oscillation results in an out-of-adjustment of the positioning of the pulse in the other half. oscillation. In addition, (e) the detent escapement shown in figure 1b does not include an anchor and therefore has a certain mechanical simplicity compared to the Swiss lever escapement. All these advantages result in a better precision and a higher autonomy of the direct-impulse escapements in comparison with indirect impulse escapements, which is why the industrial usability of the detent escapement, that is to say, impulse escapement direct, is of interest to the watch industry. However, the detent escapement has a major drawback, namely that it is not geometrically constrained to minimize the effect of shocks. So much so that the detent escapement has been used for about two centuries, especially in marine chronometers, the freedom afforded to the oscillating regulator by the detent escapement means that it cannot be used as is. in wristwatches.

For this reason, several variants using the principle of the detent escapement have been produced in the past in order to retain some of its advantages for the wristwatch. To cite some of the approaches considered in the past, we can name the Robin type escapement and its securing as performed by the applicant of the present patent application. The principles of a Robin-type escapement being known since 1791, they will not be repeated here either, but it is recalled that it is also a question of a direct impulse in which the detent spring is replaced by an anchor, as shown schematically on figure 1c . So much so that the Robin exhaust shown in figure 1c has the advantages (a) to (d) mentioned above of the detent escapement, it should be noted that its anchor is not sufficiently constrained, so that the Robin escapement is not secure in the event of impact and therefore not suitable as is for use in wristwatches. In addition, an untimely stopping of the corresponding movement can result in the total stopping over a long period of time of a watch equipped with such an escapement, since there are situations where an automatic restart, that is to say exclusively under the effect of the torque of the escape wheel without external excitation, any stray escapement such as the Robin exhaust is impossible. In fact, self-starting after running out of fuel when the barrel spring has completely discharged is not guaranteed in this kind of exhaust, since, due to the lost blow, there is the possibility of a stopping in a rest position where self-starting is impossible since the stationary balance cannot release the escape wheel.

In order to remedy the problem of securing a Robin-type escapement against impact, the applicant for the present patent application developed in 2000 a Robin-type escapement, hereinafter also referred to as an AP escapement. , which is secured against impact, as described in detail in the European patent specification EP 1 122 617 . In order to facilitate understanding of the context of the present invention without literally repeating the entire technical instruction of said European patent, it should be noted that the central interest of the watch escapement according to the European patent EP 1 122 617 is to make a Robin-type escapement for wristwatches industrially usable by providing it with a locking device replacing the stinger of a Swiss lever escapement. In fact, the use of a conventional dart such as defined above is only possible in an anchor escapement having a sufficiently large angular excursion of the anchor. As detailed in the European patent EP 1 122 617 , this is however not the case in a Robin type escapement which has a much smaller angular excursion of the anchor. The invention according to the European patent EP 1 122 617 has made it possible to make the Robin-type escapement industrially usable and to integrate it into wristwatches by proposing a specific locking device which fulfills the same function as a conventional dart but which is usable, unlike a conventional dart, also in the case of an angular excursion of the anchor smaller than in Swiss lever escapements. As shown schematically on figure 1d , this specific locking device replaces the conventional dart cooperating with a notch in the small plate of the balance, in short, by a modified dart 2.2 on its end oriented towards the balance where it has a finger 2.2.3 able to cooperate with a skirt 1.2 .1 mounted on a circular plate 1.2 of the balance and having internal 1.2.1.1 and external 1.2.1.2 walls, said skirt 1.2.1 having a notch 1.2.1.3 arranged to be traversed by said finger 2.2.3. In other words, the simple pin formed by the conventional dart and the corresponding notch of the small balance plate, working only in a plane perpendicular to the balance axis, have been replaced by a finger mounted orthogonally to the direction of longitudinal extension of the modified dart as well as the internal and external walls of said skirt including its notch, these parts having a more complex geometry and working both in the perpendicular plane - as that parallel to the axis of the balance. This measure allows the use of such a locking device also in combination with a direct impulse escapement, in particular of the Robin type, and has enabled the applicant of the present patent application, since the year 2000, to mass produce and the marketing of a Robin-type escapement in mechanical wristwatches. Furthermore, the applicant for the present patent application has further improved the securing against shocks. of a Robin type exhaust in the year 2016, as described in detail in the patent application CH 712 288 and shown at the figure 1e . In short, the improvement consists in integrating into said specific locking device, that is to say in the modified dart which lends itself to use in a Robin type escapement, a securing and guiding surface arranged and positioned so as to prevent the anchor from returning, following an untimely movement, on the path of the escape wheel. So the AP exhaust shown in figure 1d has, just like its improved variant as well as the Robin escapement, the advantages (a) to (d) mentioned above of the detent escapement and, in particular, does not need lubrication, it should be noted that 'it has the disadvantages of the Robin escapement which are independent of the protection against shocks, in particular that self-starting after running out of fuel when the barrel spring has been completely discharged is not always ensured. In addition, as mentioned in the patent application CH 712 288 and despite the generally very good functioning of an AP exhaust according to the European patent EP 1 122 617 , there are, in the version of the AP escapement of the year 2000, a few rare constellations where a collision between the finger of the stinger and the skirt of said specific locking device can occur due to the fairly tight mechanical tolerances of the parts used , this problem being reduced by the integration of said securing and guiding surface.

Another approach using the principle of the detent escapement in order to retain some of its advantages for the wristwatch was carried out by the watchmaker George Daniels who imagined a so-called double radial impulse escapement, as shown schematically on figure the. This escapement corresponds to the Robin escapement, but the lost blow is replaced by an indirect impulse produced by the intermediary of a third L pallet positioned centrally on the anchor which transmits a torque to the balance using of the ankle R. The impulse is radial and therefore does not require, in principle, lubrication and the elimination of the lost blow should, in principle, remedy the problem of the self-starting of the lost blow escapements, so that this escapement retains certain advantages of the detent escapement while avoiding certain disadvantages of the Robin escapement. On the other hand, the geometry of this double radial impulse escapement is very particular because the third pallet positioned centrally on the anchor requires a special opening of the arms of the anchor as well as a very large comparable angle of rotation of 30 °. when the pendulum is lifted. For this reason, the inlet and outlet vanes are not orthogonal to the circle of the escape wheel, which increases resistance to clearance. In addition, this exhaust is not self-starting either when the escape wheel is at rest against the anchor. In order to remedy the problems of the double radial impulse escapement, George Daniels has further developed, in addition, an escapement which is hereinafter referred to as "coaxial escapement" and shown schematically at the bottom. figure 1f . The main difference of the coaxial escapement compared to the double radial impulse escapement consists in the introduction, on the escape wheel, of a second level of teeth concentric with the usual teeth of the escape wheel, d 'where the name "coaxial". The inner row of teeth of the escape wheel is only present to facilitate the geometry of the indirect impulse, other than that, the operation of the coaxial escapement is the same as the double radial impulse escapement, This is why the coaxial exhaust can also be considered a Robin type exhaust. With this new geometry, the anchor arms can again have a geometry that allows the inlet and outlet vanes to be orthogonal to the circle of the escape wheel, so that the geometry of the coaxial escapement arms is no longer detrimental to clearance. On the other hand, the addition of an additional wheel formed by the second level of concentric teeth increases the complexity and adds mass at the escape wheel, which is detrimental to its acceleration following release. In addition, the industrialization of this escapement apparently required lubrication, which is contrary to the original motivation to use a detent escapement, or even a Robin type escapement, in order to allow, in principle, to eliminate any lubrication at this level.

Following the otherwise incomplete review of these different approaches considered in the past to integrate a detent escapement, or even a Robin-type escapement, in mechanical wristwatches, it is clear that there is still a potential for improving these escapements, the production of which remains relatively complicated as well as expensive and which are normally reserved for integration into very high-end timepieces such as wristwatches equipped with a chronograph mechanism.

Objectives of the invention

Consequently, the aim of the present invention is to remedy, at least partially, the drawbacks mentioned above and to provide a detent escapement, preferably a Robin-type exhaust and particularly preferably an exhaust of the type described. in the European patent EP 1 122 617 , respectively in the patent application CH 712 288 , while keeping the advantages of a detent escapement mentioned above, by remedying the problem of self-starting of stray escapements, by further improving the operational safety of these exhausts as well as by ensuring the feasibility in terms of industrial series production. It is also an object of the present invention to achieve such an escapement by a robust construction and as simple as possible as well as reliable during use. The solution should be suitable for integration into a Robin-type exhaust but should allow its use also in other similar watch mechanisms. Another object of the present invention is to produce a horological movement as well as a timepiece comprising such an escapement.

Solution according to the invention

To this end, the present invention provides an escapement of the aforementioned type which is distinguished by the characteristics set out in claim 1. In particular, the second mobile of the proposed escapement comprises an indirect impulse means arranged and positioned so as to be , during the entire oscillation of the regulator during normal operation of the exhaust, out of contact with the escapement wheel, while being liable to come into contact, during the other half-phase of each oscillation of the regulator member during which the escape wheel does not transmit torque to the regulator member by means of a direct impulse, with the escape wheel, in order to transmit a torque to said regulator member of the watch movement by means of an indirect pulse, via the second mobile, following an untimely movement or an untimely stopping of the watch movement. Preferably, the energy source is formed by a barrel spring and the regulating member is formed by a balance, said first mobile is formed by a plate carried by an axis of the balance and said second mobile is formed by an anchor, and said indirect impulse means is formed by an indirect impulse vane located substantially near the pivot axis of the anchor. In a preferred embodiment, the escape wheel has a number of teeth in the range from 13 to 19.

By these measures, the exhaust has the advantages of a detent escapement mentioned above, but does not present the problem of self-starting. stray escapements, given that said indirect impulse paddle comes into contact, following an untimely movement or an untimely stopping of the watch movement and during the half-phase of the oscillation of the balance during which the wheel d The escapement does not transmit torque to the balance via a direct impulse, with the escape wheel, and transmits torque to the balance via an indirect impulse via the anchor. Thus, self-starting in the event of an untimely stopping of the movement is ensured. In addition, this makes it possible to further improve the operating safety of the escapement, especially in the case of the AP escapement, because the integration of the indirect impulse pallet makes it possible to relax the tolerances of the parts involved during the exit of the finger of the dart outside the skirt, which makes it possible to avoid constellations where a collision between said finger and said skirt of the locking device can occur. Moreover, such an indirect impulse pallet can also be integrated into other types of lever escapements, so that the invention can be applied to several types of timepieces.

Other characteristics, as well as the corresponding advantages, will emerge from the dependent claims, as well as from the description which explains the invention in more detail below.

Brief description of the drawings

• Les figures la à 1f illustrent de manière schématique différents échappements selon l'art antérieur; la figure la représente par une vue en perspective un échappement à ancre suisse, la figure 1b montre par une vue de dessus un échappement à détente, la figure 1c montre par une vue de dessus un échappement Robin, la figure 1d montre par une vue de dessus un échappement selon le brevet européen EP 1 122 617 , la figure le montre par une vue de dessus l'échappement dit à double impulsion radiale et la figure 1f montre par une vue de dessus l'échappement coaxial.
• La série des figures 2a à 2j illustre de manière schématique par des vues de dessus les principales phases de fonctionnement de l'échappement selon le brevet européen EP 1 122 617 , lorsque le fonctionnement de l'échappement se déroule normalement.
• La figure 3 montre par une vue schématique de dessus un échappement selon la présente invention.
• La série des figures 4a à 4j illustre de manière schématique par des vues de dessus les principales phases de fonctionnement de l'échappement selon la présente invention, lorsque le fonctionnement se déroule normalement.
• La figure 5 illustre de manière schématique par une vue de dessus une phase de fonctionnement de l'échappement selon la présente invention, lorsque le fonctionnement de l'échappement se déroule anormalement, suite à un mouvement intempestif ou à un arrêt intempestif du mouvement horloger, le moyen d'impulsion indirecte entrant dans ce cas en contact avec la roue d'échappement et transmettant un couple à l'organe régulateur par l'intermédiaire d'une impulsion indirecte via le second mobile.

The accompanying drawings represent schematically and by way of example the prior art as well as an embodiment of the invention.

• Figures 1a to 1f schematically illustrate various exhausts according to the prior art; the figure represents it by a view in perspective a Swiss lever escapement, the figure 1b shows a top view of a detent escapement, the figure 1c shows a top view of a Robin exhaust, the figure 1d shows from a top view an escapement according to the European patent EP 1 122 617 , the figure shows a top view of the so-called radial double impulse escapement and the figure 1f shows a top view of the coaxial escapement.
• The series of figures 2a to 2j schematically illustrates by top views the main operating phases of the escapement according to the European patent EP 1 122 617 , when the exhaust operation is normal.
• The figure 3 shows a schematic top view of an escapement according to the present invention.
• The series of figures 4a to 4j schematically illustrates by top views the main operating phases of the escapement according to the present invention, when the operation takes place normally.
• The figure 5 schematically illustrates, in a top view, an operating phase of the escapement according to the present invention, when the functioning of the escapement takes place abnormally, following an untimely movement or an untimely stopping of the watch movement, the means of indirect impulse entering in this case in contact with the escape wheel and transmitting a torque to the regulating member by means of an indirect impulse via the second mobile.

Detailed description of the invention

The invention will now be described in detail with reference to the appended drawings illustrating by way of example one embodiment of the invention.

The present invention relates to an escapement intended to be integrated into a timepiece, preferably in a wristwatch. For reasons of simplification of the language used, we will speak hereinafter interchangeably of “timepiece” and of “watch”, without however wishing to limit the scope of the corresponding explanations which extend to all types of timepieces. . In particular, an escapement according to the present invention is a direct-impulse escapement, in particular an escapement of the Robin type, and the invention is, in a particularly preferred manner, carried out in an escapement as described in the European patent. EP 1 122 617 , respectively in the patent application CH 712 288 . So that the remainder of the description will only set out in detail the case of the integration of the invention into an escapement as described in the European patent. EP 1 122 617 , a use of the invention in combination with other types of exhausts is possible and the following explanations extend by analogy to any type of detent exhaust, that is to say to any type of exhaust with direct impulse, as well as various types of lever escapements.

In order to allow a better understanding of the context of the present invention, the following description will briefly recall the structure and the functioning of an escapement according to the European patent. EP 1 122 617 . Since lever escapements in general and the direct-impulse escapement described in the European patent EP 1 122 617 are known to those skilled in the art, this part of the description will be limited, as far as possible, to the facts relating to the context of the present invention. Likewise, the nomenclature used in European patent EP 1 122 617 will be used, as far as possible, also in the present description.

The figure 1d is a top view of an exhaust according to the European patent EP 1 122 617 which makes it easy to understand its structure. This escapement comprises, in generic terms, a first mobile 1 and a second mobile 2. The first mobile 1 rotates around an axis 1.1 and is capable of immobilizing the second mobile 2 in a first or a second position defined respectively by a first - and a second stop 4.1, 4.2 against which the said second mobile 2 comes to rest. The first mobile 1 is formed by a plate, respectively by a circular plate 1.2 surrounded by a skirt 1.2.1 having internal walls 1.2. 1.1 and external 1.2.1.2, said skirt 1.2.1 having a notch 1.2.1.3 arranged to be crossed by a finger 2.2.3 fixed on the second mobile 2. The second mobile 2 may, as explained in more detail in the European patent EP 1 122 617 to which reference is made with respect to this point, be provided with a rectilinear movement, so that its finger 2.2.3 always moves radially to the first rotating mobile unit 1, this configuration not being illustrated in the figures, or be equipped with an angular movement while being articulated around a pivot center 2.1, the pivot center 2.1 being chosen so that its finger 2.2.3 also moves substantially radially to the first rotating mobile device 1 when it passes through the notch 1.2 .1.3 of said skirt 1.2.1. These two variants being equivalent at the functional level for the present invention, it is only this last configuration which will be described in detail below and which is illustrated in the figures. In all cases, the second mobile 2 is immobilized in the first position when it is resting on the first stop 4.1 and its finger 2.2.3 adjoins the internal wall 1.2.1.1 of the skirt 1.2.1 and it is is immobilized in the second position when it is resting on the second stop 4.2 and its finger 2.2.3 adjoins the outer wall 1.2.1.2 of said skirt 1.2.1. For other structural details of this device, reference is made to the European patent EP 1 122 617 .

The functioning of the escapement according to the European patent EP 1 122 617 will subsequently be briefly explained with reference to the series of figures 2a to 2j which illustrates, schematically and in each position by top views, ten main phases of operation of a Robin type escapement equipped with the locking device according to the European patent EP 1122 617 , each phase being illustrated at the start of the corresponding movement. In this case, the balance of the escapement acts as the first rotating mobile 1 and the anchor acts as the second mobile 2. In the figures 2a to 2j , as in figure 1d , the balance 1 is not illustrated in full, but represented by the small circular plate 1.2 surrounded by the skirt 1.2.1 which is coaxially secured to the axis 1.1 of the balance 1, the latter still carrying the large plate which does not is not illustrated in the figures, which is also coaxially integral with the axis 1.1 and which is equipped with a direct impulse pallet 1.3 as well as an ankle 1.4. Furthermore, the anchor 2 pivotally mounted around the pivoting center 2.1 has a stinger 2.2 as described in the European patent EP 1 122 617 carrying said finger 2.2.3 of the anchor 2, a fork 2.3 cooperating with said peg 1.4, as well as an inlet rest pallet 2.4 and an outlet pallet 2.5 cooperating in a well-known manner in the a person skilled in the art with the escape wheel 3. The latter also cooperates with said direct impulse pallet 1.3 in order to directly transmit an impulse to the balance 1. The nomenclature used above and the usual function of these parts in an escapement anchor are known to those skilled in the art.

The figure 2a shows a Robin-type escapement fitted with the locking device according to the European patent EP 1 122 617 , seen from above, during the phase commonly called "entry clearance" where a tooth of the escape wheel 3 rests on the entry rest pallet 2.4 of the anchor 2, so that the escape wheel 3 cannot turn . Balance 1 is at the start of its anti-clockwise half-oscillation, seen from above according to the figure 2a , the peg 1.4 on its large plate starting to engage the fork 2.3 of the anchor 2 in order to push the latter, which was immobilized in the first position because it rests on the first stop 4.1 and its finger 2.2.3 adjoining the wall 1.2.1.1 of the skirt 1.2.1 of the small balance plate 1, so as to release the inlet rest pallet 2.4 of the anchor 2 from the tooth of the escape wheel 3 resting on it. This movement is made possible by the rotation of the balance 1 which takes the notch 1.2.1.3 arranged in said skirt 1.2.1 in a position allowing the finger 2.2.3 to cross it, so that the finger 2.2.3 passes , during the following steps, from the inner wall 1.2.1.1 to the outer wall 1.2.1.2 of the skirt 1.2.1. The movements of the different parts are symbolized in the series of figures 2a to 2j by corresponding arrows.

The figure 2b shows the escapement, again seen from above, during the phase called "drop in momentum" where the pin 1.4 on the large balance plate 1 has pushed the anchor 2 far enough so that the tooth of the wheel escapement 3 having previously rested on the inlet rest pallet 2.4 of anchor 2 is released, so that the escape wheel 3 rotates, under the effect of the driving force of the spring of the barrel transmitted clockwise by the cog of the corresponding timepiece, always seen from above.

The figure 2c shows the escapement, seen from above, during the phase called "impulse" where the escape wheel 3 has rotated, under the effect of the driving force of the barrel spring, up to the point where one of its teeth touches the direct impulse paddle 1.3 attached to the large plate of balance 1, so as to directly transmit an impulse to balance 1 in order to maintain its oscillation. During this movement, the peg 1.4 on the large balance plate 1 continues to push the anchor 2 clockwise.

The figure 2d shows the escapement, seen from above, during the phase called "entry drop" where anchor 2 has turned clockwise enough for the outlet rest pallet 2.5 of anchor 2 to have entered the trajectory of the teeth of the escape wheel 3. The latter then continues its rotation until one of its teeth engages with said output rest pallet 2.5 of the anchor 2, the escape wheel 3 being then stopped again, while the balance 1 and the anchor 2 continue their anti-clockwise half-oscillation, respectively clockwise pivoting, seen from above.

The figure 2e shows the escapement, seen from above, during the phase called "entry lost path" where the escape wheel 3 is actually stopped, one of its teeth resting on the output rest pallet 2.5 of the anchor 2 , while the balance 1 and the anchor 2 still continue their anti-clockwise half-oscillation, respectively clockwise pivoting, seen from above.

The figures 2f shows the escapement, seen from above, during the phase called “exit rest” where the escape wheel 3 is still stopped by the exit rest pallet 2.5 of anchor 2, the latter now being immobilized in the second position because resting on the second stop 4.2 and its finger 2.2.3 adjacent to the outer wall 1.2.1.2 of the skirt 1.2.1 of the small plate of the balance 1. The balance 1 in turn is in the neutral position of its anti-clockwise half-swing.

The figure 2g shows the exhaust, seen from above, during the phase called "exit release" where, at the start of this stage of operation, a escape wheel tooth 3 rests on the inlet rest pallet 2.4 of anchor 2, so that escape wheel 3 cannot yet turn. The balance 1 is at the start of its clockwise half-oscillation, seen from above according to the figure 2g , the peg 1.4 on its large plate starting to engage the fork 2.3 of the anchor 2 in the other direction in order to push the latter, which was - as mentioned above - immobilized in the second position because it was resting on the second stop 4.2 and its finger 2.2.3 adjoining the outer wall 1.2.1.2 of the skirt 1.2.1 of the small balance plate 1, in an anti-clockwise direction, seen from above, so as to release the output rest pallet 2.5 of the anchor 2 of the tooth of the escape wheel 3 resting on it. This movement is made possible by the rotation of the balance 1 which takes the notch 1.2.1.3 arranged in said skirt 1.2.1 in a position allowing the finger 2.2.3 to cross it, so that the finger 2.2.3 passes again , during the following steps, from the outer wall 1.2.1.2 to the inner wall 1.2.1.1 of the skirt 1.2.1.

The figure 2h shows the escapement, seen from above, during the phase called "exit fall" where the pin 1.4 on the large balance plate 1 has pushed the anchor 2 far enough so that the tooth of the escape wheel 3 having previously resting on the output rest pallet 2.5 of the anchor 2 is released, so that the escape wheel 3 turns, under the effect of the driving force of the spring of the barrel transmitted by the gear train. the corresponding timepiece, clockwise, seen from above. During this movement, the balance 1 continues its half-oscillation clockwise and the peg 1.4 on the large plate of the balance 1 continues to push the anchor 2 anti-clockwise, so that the rest pallet input 2.4 of anchor 2 re-enters the path of the teeth of escape wheel 3. The latter then continues its rotation until one of its teeth engages with said rest pallet d 2.4 entry of the anchor 2, the escape wheel 3 then being stopped again. During this phase, escape wheel 3 does not transmits no impulse to the balance wheel 1, because the direct impulse pallet 1.3 is arranged and placed in such a way on the large plate that it is not touched by the teeth of the escape wheel 3 when the balance wheel 1 performs its half-oscillation clockwise.

The figure 2i shows the escapement, seen from above, during the phase called "lost exit path" where the escape wheel 3 is actually stopped, one of its teeth resting on the inlet rest pallet 2.4 of the anchor 2 , while the balance 1 and the anchor 2 still continue their clockwise half-oscillation, respectively the anti-clockwise pivoting, seen from above.

The figure 2j shows the escapement, seen from above, during the phase called "entry rest" where the escape wheel 3 is still stopped by the inlet rest pallet 2.4 of the anchor 2, the latter being again immobilized in the first position because resting on the first stop 4.1 and its finger 2.2.3 adjoining the internal wall 1.2.1.1 of the skirt 1.2.1 of the small plate of the balance 1. The balance 1 in turn is at the point dead of its clockwise half-oscillation, ready to start a new oscillation cycle, so that the above-described steps are repeated.

In this context, it should be noted that the description given above of the functioning of the escapement according to the European patent EP 1 122 617 is also valid for the exhaust according to the patent application CH 712 288 and, in principle, applies by analogy to any Robin-type escapement, or even to any lever escapement, having a lost blow, that is to say having a half-phase during each oscillation of the regulatory organ during which there is no pulse.

The figure 3 shows a schematic top view of an exhaust according to the present invention. It emerges that, in generic terms, such an escapement is suitable for being integrated into a watch movement and arranged to transmit a torque originating from an energy source of said watch movement to an oscillating regulator member of said watch movement, the member regulator of the watch movement comprising a first mobile 1 and the escapement comprising a second mobile 2 as well as an escape wheel 3. The first mobile 1 cooperates with the second mobile 2 while being capable of immobilizing the second mobile 2 in a first or a second position defined respectively by a first and a second stop 4.1, 4.2 against which the said second mobile 2 comes to rest 2. The escape wheel 3 is arranged so as to transmit, during a half-phase of each oscillation of the regulating organ, a torque to said regulating organ via a direct impulse. In addition, said second mobile 2 comprises an indirect impulse means arranged and positioned so as to be, during the entire oscillation of the regulator member during normal operation of the exhaust, out of contact with the escape wheel 3. , while being capable of coming into contact, during the other half-phase of each oscillation of the regulator member during which the escape wheel 3 does not transmit torque to the regulator member via d 'a direct impulse, with the escape wheel 3, in order to transmit a torque to said regulating member of the watch movement by means of an indirect impulse, via the second mobile 2, following an untimely movement or an untimely stop watch movement, in particular to ensure self-starting of the watch movement.

In most concrete embodiments of a horological escapement, respectively of a watch movement, said energy source is formed by a barrel spring and said regulating member is formed by a balance, said first mobile 1 of the regulating member of the watch movement being conventionally formed by a plate 1.2 carried by an axis 1.1 of the balance.

Moreover and as mentioned in more detail in the European patent EP 1 122 617 , the second mobile 2 of the escapement can, in principle, be provided with an angular movement or a rectilinear movement. In the first case, said second mobile 2 of the escapement is preferably formed by an anchor 2, said plate 1.2 carried by an axis 1.1 of the balance being able to cooperate with said anchor 2.

As regards more particularly the production of said means of indirect impulse 2.6 of an escapement according to the present invention, it is preferably formed by an indirect impulse vane 2.6 located substantially near the pivot axis of said second mobile 2 , respectively of said anchor 2. Preferably, said indirect impulse vane 2.6 is located on the first half, near said pivot axis, of the arm of the anchor 2 carrying the output rest vane 2.5, as illustrated. to the figure 3 . This indirect impulse pallet 2.6 can be made in one piece with the anchor 2 or by a separate part mounted on the anchor 2. Preferably, the indirect impulse pallet is made by a separate part and made of a material. low friction and low wear, such as ruby or sapphire.

As regards the production of the escape wheel 3 of an escapement according to the present invention, it comprises, in a preferred embodiment and illustrated in figure 3 a number of teeth in the range of 13 to 19.

In addition, an escapement according to the present invention comprises, in a preferred embodiment, a locking device according to European patent EP 1 122 617 , the structure and operation of such a device having been described above and applying identically to an escapement according to the present invention comprising such a locking device. In a particularly preferred embodiment, an escapement according to the present invention also comprises at least one securing and guiding surface as mentioned above as well as described in detail in the patent application. CH 712 288 , this description of the structure and operation of such a securing and guiding surface similarly applying to an exhaust according to the present invention comprising such a securing and guiding surface.

With regard to the operation of an escapement according to the present invention, the figures 4a to 4j show schematic top views of the main operating phases of the escapement according to the present invention, when operation takes place normally, the invention being in these figures applied to the escapement according to the European patent EP 1 122 617 . In this context, it should be noted that the description given above, with reference to figures 2a to 2j , the functioning of the escapement according to the European patent EP 1 122 617 is fully valid for this embodiment of an escapement according to the present invention. This remark also applies to the embodiment of an escapement according to the present invention comprising at least one securing and guiding surface according to the patent application. CH 712 288 , respectively applies by analogy to all embodiments of an escapement according to the present invention, that is to say to any Robin-type escapement, or even to any lever escapement, having a stray blow, that is to say having a half-phase during each oscillation of the regulating member during which there is no pulse, and being equipped with an indirect impulse means 2.6 according to the present invention. Indeed, apart from the presence of said one indirect impulse means 2.6 on the second mobile 2 and a different number of teeth of the escape wheel 3, the structure and normal operation of an escapement according to the present invention are identical to those of the exhaust according to the European patent EP 1 122 617 , respectively to those of a corresponding Robin type escapement, given that the indirect impulse means 2.6 only take an active role when an abnormal situation occurs. Therefore, all of the above explanations in the context of the series of figures 2a to 2j are valid for the normal operation of an exhaust according to the present invention as illustrated in the series of figures 4a to 4j which show the same main phases of normal operation of an escapement according to the present invention as the series of figures 2a to 2j . For reasons of simplicity, these explanations will not be repeated here while applying by analogy to the series of figures 4a to 4j .

As regards the operation of an escapement according to the present invention when an anomaly occurs, in particular following an untimely movement or an untimely stopping of the watch movement, the figure 5 illustrates a schematic top view of an operating phase of the escapement according to the present invention during which the indirect impulse means 2.6 takes an active role. Indeed, when the operation of the escapement takes place abnormally, following an untimely movement or an untimely stop of the watch movement, the indirect impulse means 2.6 comes into contact with one of the teeth of the escape wheel 3 and transmits a torque to the regulating member by means of an indirect impulse via the second mobile 2. The indirect impulse paddle 2.6 can also give an impulse to the balance when its amplitude decreases following the unwinding of the barrel, which one can designate as a “pulse on demand”, this case not being illustrated in the figures. The present invention thus makes it possible to avoid the drawbacks of prior art exhausts mentioned in the introduction by proposing an escapement which, in addition to the components of the escapement according to the European patent EP 1 122 617 , respectively in general of a detent escapement, or even of the Robin type, also comprises said indirect impulse means 2.6, preferably in the form of an indirect impulse vane mounted near the pivot axis of the anchor 2, this indirect impulse means 2.6 remaining out of contact with the escape wheel 3 during the entire oscillation of the regulating member during normal operation of the exhaust and only intervening during abnormal operation to perform an indirect impulse.

In this context, we can add that, some fifty years ago, while making observations with a high-speed camera, watchmakers were surprised to observe that during the operation of the lever escapement, after its released by the balance, the escape wheel follows a substantial path before one of its teeth catches up with one of the pallets of the anchor. In fact, almost a third of the length of the inlet and outlet vanes of a conventional anchor is not used because the corresponding tooth on the escape wheel has not yet made contact. This is also the case for direct impulse escapements where the teeth of the escapement wheel must catch up with the impulse vane located on the large balance plate in order to effect a direct impulse. In either case, this is generally considered to be a fault and various means are used to minimize it. An escapement according to the present invention having an indirect impulse pallet on the anchor which is not at all caught by the teeth of the escape wheel during normal operation of the escapement, that is to say -to say which does not participate at all in the normal functioning of the escapement, but which intervenes only during abnormal functioning, is therefore in a certain way contrary to the traditional technical instruction in the field of watchmaking . On the other hand, in the event of loss of amplitude, of shock, or of tendency to stop escapement, one of the teeth of the escape wheel comes into contact with the indirect impulse vane and allows an indirect impulse to be carried out, which if necessary leads to automatic restart, given that the presence of the vane of indirect impulse 2.6 brings an additional geometric constraint which is exploited during a specific phase of the operation of the escapement and whose geometry can be adapted according to the needs according to the concrete application case, for example by varying the l 'location and / or shape of the indirect impulse paddle. It can also be noted here that the above remark is underlined by the configuration of the double radial impulse escapement mentioned in the introduction, given that the third impulse vane L positioned centrally on the anchor of this exhaust, as seen on the figure 1e , systematically transmits a torque to the balance at each half-phase of the oscillation of the regulating organ during which the escape wheel does not transmit torque to the regulating organ via a direct impulse, c ' that is, this third impulse vane always participates in the normal operation of the double radial impulse escapement. Consequently, the present invention can also be realized in an escapement of the double radial impulse type or in the coaxial escapement mentioned in the introduction by replacing the third impulse vane present in and still participating in the normal operation of these exhausts by an indirect impulse vane 2.6 according to the present invention which only intervenes during abnormal operation of the escapement.

In view of the arrangement and operation of a horological escapement according to the present invention as described above, a person skilled in the art understands that the present invention can be implemented in any type of direct impulse escapement, in particular in a Robin exhaust and, particularly preferably, in an exhaust according to the European patent EP 1 122,617 and according to the patent application CH 712 288 . In general, the present invention can be implemented in any type of lever escapement having a lost blow, without it being necessary or possible to mention all the cases and all the corresponding details here. In view of the technical instruction appearing above, a person skilled in the art also understands that the present invention relates not only to such an escapement, but also to a watch movement comprising a source of energy, a regulating member, a gear train as well as 'such a watch escapement. In addition, the present invention also relates to a timepiece, preferably a mechanical wristwatch, comprising such a horological escapement, respectively such a watch movement. Preferably, it is a wristwatch having a chronograph or split-seconds mechanism in which the advantages of a direct-impulse escapement can be exploited in a particularly advantageous manner.

A watch escapement according to the present invention then makes it possible to obviate the problem of the self-starting of the escapements without stopping, given that its indirect impulse paddle comes into contact, for example following an untimely movement or a stop. of the watch movement and during the half-phase of the balance wheel oscillation during which the escape wheel does not transmit torque to the balance by means of a direct impulse, with the escape wheel and transmits by the intermediary of an indirect impulse via the anchor a torque to the balance which is sufficient to restart the watch movement. Simultaneously, the present invention allows, in the event of application to the escapement according to the European patent EP 1 122 617 and the one according to the patent application CH 712 288 , to secure the second mobile 2 in a complementary manner during the operating phase of the device during which the finger 2.2.3 fixed to the second mobile 2 passes through the notch 1.2.1.3 of said skirt 1.2.1 of the first mobile 1, to so that the notch 1.2.1.3 in the skirt 1.2.1 can be enlarged. Thus, the tolerances of the parts involved during the exit of the finger from the dart outside the skirt can be relaxed, which makes it possible to avoid constellations where a collision between said finger and said skirt of the locking device can occur. The indirect impulse means 2.6 then plays a role of self-starting means as well as, in a subsidiary manner, a role of securing means.

In short, the present invention makes it possible to produce a watch escapement which has the advantages of a detent escapement mentioned above and whose self-starting in the event of an untimely stopping of the movement is ensured, so that it does not does not present the problem of auto-starting of stray escapements. In addition, the present invention makes it possible to further improve the operating safety of the escapement, in particular in the case of the AP escapement, by making it possible to relax the tolerances of the parts involved when the finger comes out of the dart outside of the skirt and thus avoiding constellations where a collision between said finger and said skirt of the locking device may occur. Furthermore, the proposed construction, consisting mainly of the integration of an indirect impulse vane, is simple and robust as well as reliable during operation of the escapement. Such an indirect impulse vane can be integrated into several types of detent and / or lever escapements having a lost shot, so that the invention can be flexibly applied to several types of parts. watchmaking. In particular, the invention can be applied, preferably, in mechanical wristwatches, in particular in wristwatches equipped with a chronograph or split-seconds mechanism.

Claims (15)

1. A horological detent escapement adapted to be integrated in a horological movement and arranged to transmit a torque originating from an energy source of said horological movement to an oscillating regulating organ of said horological movement, the regulating organ of the horological movement comprising a first mobile body (1) and the escapement comprising a second mobile body (2) as well as an escapement wheel (3), said first mobile body (1) cooperating with said second mobile body (2) by being capable of stopping the second mobile body (2) in a first or a second position defined respectively by a first and a second banking (4.1, 4.2) against which said second mobile body (2) comes to rest, said escapement wheel (3) being arranged so as to transmit, during a half-phase of each oscillation of the regulating organ, a torque to said regulating organ by means of a direct impulse, characterized in that said second mobile body (2) comprises an indirect impulse means (2.6) arranged and positioned so as to be, during the whole oscillation of the regulating organ during the normal functioning of the escapement, out of contact with the escapement wheel (3), whilst being capable of coming into contact, during the other half-phase of each oscillation of the regulating organ during which the escapement wheel (3) does not transmit torque to the regularing organ by means of a direct impulse, with the escapement wheel (3), so as to transmit a torque to said regulating organ of the horological movement by means of an indirect impulse, via the second mobile body (2), following an inadvertent movement or an inadvertent stoppage of the horological movement.
2. The horological escapement according to the preceding claim, characterized in that said energy source is formed by a barrel spring and that said regulating organ is formed by a balance.
3. The horological escapement according to the preceding claim, characterized in that said first mobile body (1) of the regulating organ of the horological movement is formed by a roller (1.2) carried by an axis (1.1) of the balance.
4. The horological escapement according to one of the preceding claims, characterized in that said second mobile (2) of the escapement is given an angular movement or a rectilinear movement.
5. The horological escapement according to the preceding claims 3 and 4, characterized in that said second mobile body (2) of the escapement is formed by pallets (2), said roller (1.2) being adapted to cooperate with said pallets (2).
6. The horological escapement according to one of the preceding claims, characterized in that said indirect impulse means is formed by an indirect impulse pallet-stone (2.6) situated substantially close to the pivoting axis of said second mobile body (2), respectively said pallets (2), in particular by an indirect impulse pallet-stone (2.6) situated on the first half, close to said pivoting axis, of the arm of the pallets (2) carrying the exit lock pallet-stone (2.5).
7. The horological escapement according to the preceding claim, characterized in that said indirect inpulse pallet-stone (2.6) is made from a low-friction and low-wear material, preferably from ruby or sapphire.
8. The horological escapement according to one of the preceding claims 5 to 7, characterized in that said escapement wheel (3) comprises a number of teeth situated in the range of 13 to 19.
9. The horological escapement according to one of the preceding claims 3 to 8, characterized in that the first mobile body (1) formed by said roller (1.2) comprises a circular plate surrounded by a skirt (1.2.1) having internal (1.2.1.1) and external (1.2.1.2) walls, said skirt (1.2.1) having a notch (1.2.1.3) arranged so as to be traversed by a finger (2.2.3) fixed on the second mobile body (2), the second mobile body (2) being stopped in the first position when it is resting on the first banking (4.1) and its finger (2.2.3) adjoins the internal wall (1.2.1.1) of the skirt (1.2.1) and being stopped in the second position when it is resting on the second banking (4.2) and its finger (2.2.3) adjoins the external wall (1.2.1.2) of said skirt (1.2.1).
10. The horological escapement according to the preceding claim, characterized in that said second mobile body (2) comprises at least one securing and guiding surface oriented in a direction substantially opposed to said finger (2.2.3) so as to secure said second mobile body (2) during the functioning phase of the escapement during which the finger (2.2.3) fixed on the second mobile body (2) traverses the notch (1.2.1.3) of said skirt (1.2.1) of the first mobile body (1).
11. The horological escapement according to the preceding claim, characterized in that said securing and guiding surface is arranged and positioned so as to be, during the impulse phase of the balance (1) by the escapement wheel (3), at exterior periphery of the trajectory of the escapement wheel (3) of said escapement, so as to be capable of coming into contact with said escapement wheel (3) in order to secure the second mobile body (2), respectively the pallets (2), preventing it from returning, following an inadvertent movement, on the trajectory of the escapement wheel (3).
12. The horological escapement according to one of the preceding claims, characterized in that it is a direct impulse escapement comprising an escapement wheel (3) transmitting the impulse directly to the balance (1), preferably an escapement of the Robin type.
13. A horological movement comprising an energy source, a regulating organ (1), an escapement and a train, characterized in that the escapement is a horological escapement according to one of the preceding claims 1 to 12.
14. A timepiece, preferably a wristwatch, characterized in that it comprises a horological escapement according to one of the preceding claims 1 to 12, respectively a horological movement according to the preceding claim.
15. The timepiece according to the preceding claim, characterized in that it is a chronograph watch or split-time counter watch.

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