EP3584641A1 - Automatically starting and secured detent escapement for timepieces - Google Patents

Abstract

The present invention relates to a detent watch escapement capable of being integrated into a watch movement and arranged to transmit a torque from an energy source of said watch movement to an oscillating regulating member of said watch movement, the regulating member of the watch movement comprising a first mobile (1) and the exhaust comprising a second mobile (2) and an escape wheel (3), said first mobile (1) cooperating with said second mobile (2) 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 said second mobile (2) comes to bear, said escape wheel (3) being arranged so as to transmit, during a half-phase of each oscillation of the regulating member, a torque to said regulating member by means of a direct pulse. The exhaust is distinguished by the fact that said second mobile (2) comprises an indirect impulse means (2.6) arranged and positioned so as to be, throughout the oscillation of the regulating member during normal operation of the exhaust, out of contact with the escape wheel (3), while being likely to come into contact, during the other half-phase of each oscillation of the regulating member during which the escape wheel (3) does not transmit torque to the regulating member by means of 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 of the watch movement. The present invention also relates to a watch movement, respectively a timepiece equipped with such an escapement.

Description

Fields of invention

The present invention relates to a timepiece escapement of the detent type as well as a timepiece movement and a timepiece, in particular a mechanical watch, comprising such an escapement. More particularly, the present invention relates to a detent watch escapement capable of being integrated into a watch movement and arranged to transmit a torque coming from an energy source of said watch movement to an oscillating regulating member of said watch movement, the regulating 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 by 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 said second mobile member bears, said escape wheel being arranged so as to transmit, during a half-phase of each oscillation of the regulating member, a torque to said regulating member through a direct impulse.

State of the prior art

As the escapement is one of the cornerstones of a watch movement, there are a large number of different types of watch escapements. In general, within the framework of mechanical timepieces, there is the family of permanent contact escapements in which the oscillating regulating member of the movement, the balance wheel, is constantly in contact with a part of the escapement and the family of free escapements in which the balance wheel has no contact with the escapement except during release and impulse.

The family of free exhausts mentioned last includes itself several types of exhausts. In addition, this family includes the Swiss lever escapement, which represents the vast majority of watch escapements currently used in wristwatches with mechanical movement. Those skilled in the art are fully aware of the components and 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 location. Likewise, a person skilled in the art knows that a Swiss anchor escapement is usually fitted with a part called "dart" g in order to avoid what is known in watchmaking under the name "overturning" of the anchor c which results in the immediate stopping of the balance wheel, 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 travels its additional arc and the anchor c is positioned against one or the other. limitation stops e, for example following a shock which moves the anchor c from its target position and brings it prematurely against the other limitation stop e, so that the pin t of the large plate i of the pendulum will no longer meet the entrance but accidentally meets the reverse of one of the two horns of the fork f of the anchor c, resulting in the immediate stopping of the pendulum. 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 anchor escapement, makes it possible to avoid this problem because the dart g works with the small plate h carried by the axis of the balance j and prevents accidental movements of the fork f during the additional swing arc of the balance. Due to these geometric constraints, a Swiss anchor escapement is fairly well secured against impact and lends itself particularly well to use in wristwatches.

The family of free exhausts also includes the so-called detent escapement which is illustrated schematically in the figure 1b and which is considered 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 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 escapement wheel to the balance wheel via 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, of which an extension is in the field of action of a pallet of clearance c, this 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 an impulse to the balance. The impulse is therefore transmitted directly by the escape wheel to the balance wheel, which results in a number of advantages. We also take into account the fact that (a) the escapement disturbs the pendulum to a lesser extent since there is only one pulse per period of oscillation, compared to the escapement with Swiss anchor which disturbs the pendulum twice per period. In other words, the detent escapement has what a person skilled in the art knows by the name "lost shot", that is to say a half-oscillation without impulse. A direct impulse escapement also has (b) better efficiency due to the direct transmission of the impulse from the escapement wheel to the balance wheel, without passing through an additional component such as the anchor which drives loss of efficiency. In addition, (c) thanks to the fact that the impulse takes place along a direction which is orthogonal to the line connecting the centers of the escapement wheel and of the balance wheel 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 eliminates the need for lubrication. Furthermore, (d) the fact that there is a knockout allows precise adjustment of the position of the single pulse by oscillation relative to the dead center of the oscillator, which is not possible in escapements at Swiss anchor having two pulses per period of oscillation, since adjusting the positioning of the pulse before or after neutral in one half oscillation results in an adjustment of the positioning of the pulse in the other half oscillation. In addition, (e) the detent escapement illustrated in figure 1b does not have an anchor and therefore has a certain mechanical simplicity compared to the Swiss anchor escapement. All these advantages result in better precision and longer autonomy of direct impulse escapements in comparison with indirect impulse exhausts, which is why the industrial exploitability of the detent escapement, i.e. impulse direct, is interesting for the watch industry. The detent escapement however 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, notably in marine chronometers, the freedom given to the oscillating regulating member by the detent escapement means that it cannot be used as it is. in wrist watches.

For this reason, several variants using the detent escapement principle have been made in the past in order to retain some of its advantages for the wristwatch. To cite some of the approaches envisaged in the past, we can name the Robin type exhaust and its securing as carried out by the applicant of this patent application. The principles of a Robin type exhaust being known since 1791, they will not be repeated here either, but it is recalled that it is also an exhaust with direct impulse in which the detent spring is replaced by an anchor, as illustrated schematically in the figure 1c . So much so that the Robin exhaust illustrated in figure 1c has the advantages (a) to (d) mentioned above of the detent escapement, it must be noted that its anchor is not sufficiently constrained, so that the Robin exhaust is not secure in the event of impacts and therefore does not lend itself as such for use in wristwatches. In addition, an untimely stop of the corresponding movement can result in the total stop over a long period 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 blow-out escapement such as the Robin escapement is impossible. In fact, self-starting after a dry breakdown where the barrel spring has fully discharged is not ensured in this type of exhaust, since, due to the blow, there is the possibility of a stop 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 exhaust against shocks, the applicant for this patent application developed in the year 2000 a Robin type exhaust, also referred to below as AP exhaust. , which is secure against impact, as described in detail in the specification of the European patent EP 1,122,617 the content of which is incorporated into the present description by reference. In order to facilitate understanding of the context of the present invention without literally repeating the entire technical instruction of the said European patent, it should be noted that the central interest of the timepiece escapement according to the European patent EP 1,122,617 is to make a Robin type escapement industrially exploitable for wristwatches by providing it with a locking device replacing the stinger of a Swiss anchor escapement. In fact, the use of a conventional stinger 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 made it possible to industrially exploit the Robin type escapement 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 the escapements with Swiss anchor. As shown schematically in the figure 1d , this specific locking device replaces the conventional dart cooperating with a notch in the small balance plate, in short, by a modified dart 2.2 on its end oriented towards the balance where it has a finger 2.2.3 capable of cooperating with a skirt 1.2 .1 mounted on a circular plate 1.2 of the pendulum 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 crossed by said finger 2.2.3. In other words, the simple pin formed by the conventional dart and the corresponding notch in 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 sting as well as the internal and external walls of said skirt including its notch, these parts having a more complex geometry and working as well in the perpendicular plane - as that parallel to the axis of the pendulum. 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 for this patent application, since 2000, to produce in series. and the marketing of a Robin type escapement in mechanical wristwatches. Furthermore, the applicant of this patent application has further improved the security against shocks a Robin type exhaust in the year 2016, as described in detail in the patent application CH 712 288 the content of which is incorporated into the present description by reference. In short, the improvement consists in integrating into said specific locking device, that is to say in the modified stinger which lends itself to use in a Robin type exhaust, a securing and guiding surface arranged and positioned so as to prevent the anchor from coming back, following an untimely movement, on the trajectory of the escape wheel. So that the AP exhaust illustrated in figure 1d has, like its improved variant as well as the Robin exhaust, the advantages (a) to (d) mentioned above of the detent exhaust and, in particular, does not need lubrication, it should be noted that 'it has the disadvantages of the Robin escapement which are independent of securing against shocks, in particular that self-starting after a dry breakdown where the barrel spring is completely discharged is not always guaranteed. 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 1122 617 , there are, in the version of the AP escapement of the year 2000, some rare constellations where a collision between the finger of the stinger and the skirt of said specific locking device can occur because of 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 an escapement known as a double radial impulse, as illustrated schematically in the figure it. This escapement corresponds to the Robin escapement, but the lost shot is replaced by an indirect impulse produced via a third pallet L 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, in principle, require lubrication and the suppression of the lost shot should, in principle, remedy the problem of the self-starting of the blowback escapements, so that this exhaust retains certain advantages of the detent escapement while avoiding certain disadvantages of the Robin exhaust. On the other hand, the geometry of this escapement with double radial impulse 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 angle of rotation of 30 ° comparable when the pendulum is lifted. For this reason, the entry and exit paddles are not orthogonal to the circle of the escape wheel, which increases resistance to clearance. In addition, this escapement is not self-starting either when the escapement wheel is at rest against the anchor. In order to remedy the problems of the exhaust with double radial impulse, George Daniels has further developed, in addition, an exhaust which is designated hereinafter “coaxial exhaust” and illustrated schematically in the figure 1f . The main difference of the coaxial escapement compared to the escapement with double radial impulse consists in the introduction, on the escapement wheel, of a second level of teeth concentric with the usual teeth of the escapement 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, apart from that, the operation of the coaxial escapement is identical to that of the escapement with double radial impulse, this is why the coaxial exhaust can also be considered as a Robin type exhaust. With this new geometry, the anchor arms can again have a geometry allowing the input and output pallets to be orthogonal to the circle of the escapement wheel, so that the geometry of the arms of the coaxial escapement is no longer detrimental to release. 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 the release. In addition, the industrialization of this exhaust apparently required lubrication, which is contrary to the original motivation to use a detent exhaust, or even a Robin type exhaust, in order to allow, in principle, to remove all lubrication at this level.

Following the review, moreover incomplete, of these different approaches envisaged 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 improve these escapements, the production of which remains relatively complicated as well as costly 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 make available 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 retaining the advantages of a detent escapement mentioned above, by overcoming the problem of self-starting of blow-by-end escapements, by further improving the operating safety of these escapements as well as by guaranteeing the feasibility in terms of industrial mass production. It is also an object of the present invention to produce such an exhaust by a robust construction which is as simple as possible as well as reliable in 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 timepiece movement as well as a timepiece comprising such an escapement.

Solution according to the invention

To this end, the present invention provides an exhaust of the aforementioned type which is distinguished by the characteristics set out in claim 1. In particular, the second mobile of the proposed exhaust comprises an indirect impulse means arranged and positioned so as to be , during the entire oscillation of the regulating member during normal operation of the exhaust, out of contact with the escapement wheel, while being likely to come into contact, during the other half-phase of each oscillation of the regulating member during which the escapement wheel does not transmit torque to the regulating member by means of a direct pulse, with the escapement wheel, in order to transmit a torque to said regulating member of the watch movement via an indirect impulse, via the second mobile, following an untimely movement or an untimely stop of the watch movement. Preferably, the energy source is formed by a barrel spring and the regulating member is formed by a pendulum, said first mobile is formed by a plate carried by a pendulum axis and said second mobile is formed by an anchor, and said indirect impulse means is formed by an indirect impulse paddle 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. blow-out escapements, since said indirect impulse palette comes into contact, following an untimely movement or an untimely stop of the watch movement and during the half-phase of the pendulum oscillation during which the wheel d The escapement does not transmit torque to the balance wheel via a direct impulse, with the escape wheel, and transmits torque to the balance wheel via an indirect impulse via the anchor. Thus, self-starting in the event of untimely stopping of the movement is ensured. In addition, this makes it possible to further improve the operating safety of the escapement, in particular in the case of the AP escapement, because the integration of the indirect impulse palette makes it possible to relax the tolerances of the parts involved during the sticking out of the stinger finger 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. Furthermore, such an indirect pulse palette can also be integrated into other types of anchor 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 setting out the invention below in more detail.

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 show schematically and by way of example the prior art as well as an embodiment of the invention.

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

Detailed description of the invention

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

The present invention relates to an escapement intended to be integrated in a timepiece, preferably in a wristwatch. For reasons of simplification of the language used, we will speak hereinafter indifferently of "timepiece" and "watch", without however wanting to limit the scope of the corresponding explanations which extend to any type of timepiece . In particular, an exhaust according to the present invention is a direct impulse exhaust, in particular a Robin type exhaust, and the invention is, in a particularly preferred manner, produced in an exhaust as described in the European patent. EP 1,122,617 , respectively in the patent application CH 712 288 . So that the rest of the description will detail only the case of integrating the invention into an exhaust 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 direct impulse, as well as various types of anchor escapement.

In order to better understand the context of the present invention, the following description will briefly recall the structure and operation of an exhaust according to the European patent EP 1,122,617 . Since the anchor 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 facts related to the context of the present invention. Similarly, the nomenclature used in the 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 exhaust 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 said second mobile 2 bears. The first mobile 1 is produced 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 can, 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 his finger 2.2.3 always moves radially to the first rotary mobile 1, this configuration not being illustrated in the figures, or be provided with an angular movement while being articulated around a pivot center 2.1, the pivot center 2.1 being chosen so that his finger 2.2.3 also moves substantially radially to the first rotary mobile 1 when it crosses 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 latter 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 in abutment on the first stop 4.1 and when its finger 2.2.3 adjoins the internal wall 1.2.1.1 of the skirt 1.2.1 and it finds itself 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 .

How the exhaust works according to the European patent EP 1,122,617 will be briefly explained below with reference to the series of Figures 2a to 2d which illustrates, schematically and at each position by top views, ten main phases of operation of a Robin type exhaust 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 2d , as in the 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 integral with the axis 1.1 of the balance 1, the latter still carrying the large plate which does is not illustrated in the figures, which is also coaxially integral with the axis 1.1 and which is equipped with a direct impulse paddle 1.3 as well as a pin 1.4. Furthermore, the anchor 2 pivotally mounted around the pivot center 2.1 has a dart 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 pin 1.4, as well as an entry rest pallet 2.4 and an exit pallet 2.5 cooperating in a manner well known to the skilled in the art with the escape wheel 3. The latter also cooperates with said direct impulse palette 1.3 in order to directly transmit an impulse to the balance wheel 1. The nomenclature used above and the usual function of these parts in an escapement anchors are known to those skilled in the art.

The figure 2a shows a Robin type exhaust 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 rotate . The pendulum 1 is located at the start of its half-oscillation in the counterclockwise direction, seen from above according to the figure 2a , the ankle 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 internal 1.2.1.1 of the skirt 1.2.1 of the small balance wheel plate 1, so as to disengage the entry rest pallet 2.4 from the anchor 2 from the tooth of the escape wheel 3 resting on it. This movement is made possible by the rotation of the pendulum 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 internal wall 1.2.1.1 to the external wall 1.2.1.2 of the skirt 1.2.1. The movements of the different pieces are symbolized in the series of figures 2a to 2d by corresponding arrows.

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

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

The figure 2d shows the escapement, seen from above, during the phase called "entry fall" where the anchor 2 has turned sufficiently clockwise so that the exit rest pallet 2.5 of the anchor 2 has 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 outlet rest pallet 2.5 of the anchor 2, the escape wheel 3 then being stopped again, while the balance 1 and the anchor 2 continue their half-oscillation in the counterclockwise direction, respectively pivoting in the clockwise direction, seen from above.

The figure 2e shows the exhaust, seen from above, during the phase called "lost entry path" where the escape wheel 3 is effectively 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 half-oscillation in the counterclockwise direction, respectively pivoting in the clockwise direction, seen from above.

The figures 2f shows the exhaust, seen from above, during the phase called "exit rest" where the escape wheel 3 is always stopped by the exit rest pallet 2.5 of the anchor 2, the latter now being immobilized in the second position because resting on the second stop 4.2 and his finger 2.2.3 adjoining the external wall 1.2.1.2 of the skirt 1.2.1 of the small balance plate 1. The balance 1 in turn is in the neutral position of its anti-clockwise half-oscillation.

The figure 2g shows the exhaust, seen from above, during the phase called "exit clearance" where, at the start of this stage of operation, 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 yet rotate. The pendulum 1 is at the start of its clockwise half-oscillation, seen from above according to the figure 2g , the pin 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 resting on the second stop 4.2 and his finger 2.2.3 adjoining the external wall 1.2.1.2 of the skirt 1.2.1 of the small balance plate 1, counterclockwise, seen from above, so as to release the outlet 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 pendulum 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 external wall 1.2.1.2 to the internal 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 wheel 1 has pushed the anchor 2 far enough so that the tooth of the escape wheel 3 having previously rested on the output rest pallet 2.5 of the anchor 2 becomes free, so that the escape wheel 3 rotates, under the effect of the driving force of the barrel spring transmitted by the gear train of the corresponding timepiece, clockwise, seen from above. During this movement, the balance 1 continues its half-oscillation clockwise and the pin 1.4 on the large plate of the balance 1 continues to push the anchor 2 counterclockwise, so that the rest pallet input 2.4 of the anchor 2 again enters the path of the teeth of the escape wheel 3. The latter then continues its rotation until one of its teeth engages with said rest pallet d entry 2.4 of the anchor 2, the escape wheel 3 then being stopped again. During this phase, the escape wheel 3 does not transmits no impulse to the pendulum 1, because the direct impulse paddle 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 pendulum 1 performs its half-oscillation clockwise.

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

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

In this context, it should be noted that the description given above of the operation of the exhaust 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 anchor escapement, having a lost shot, that is to say having a half-phase during each oscillation of the regulator during which there is no impulse.

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

In most concrete embodiments of a timepiece escapement, respectively of a timepiece 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 watch movement regulator being conventionally formed by a plate 1.2 carried by an axis 1.1 of the balance.

Furthermore and as mentioned in more detail in the European patent EP 1,122,617 , the second mobile 2 of the exhaust 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 indirect impulse means 2.6 of an exhaust according to the present invention, it is preferably formed by an indirect impulse paddle 2.6 situated substantially near the pivot axis of said second mobile 2 , respectively of said anchor 2. Preferably, said indirect pulse pallet 2.6 is located on the first half, near said pivot axis, of the arm of anchor 2 carrying the output rest pallet 2.5, as illustrated to the figure 3 . This indirect impulse paddle 2.6 can be manufactured in one piece with the anchor 2 or by a separate piece mounted on the anchor 2. Preferably, the indirect impulse paddle is made by a separate piece and made of a material low friction and low wear, such as ruby or sapphire.

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

In addition, an exhaust according to the present invention comprises, in a preferred embodiment, a locking device according to the European patent EP 1,122,617 , the structure and operation of such a device having been described above and applying in an identical manner to an exhaust according to the present invention comprising such a locking device. In a particularly preferred embodiment, an exhaust according to the present invention also comprises at least one securing and guiding surface as mentioned above 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 likewise applying in an identical manner to an exhaust according to the present invention comprising such a securing and guiding surface.

With regard to the operation of an exhaust according to the present invention, the figures 4a to 4d show by schematic views from above the main operating phases of the exhaust according to the present invention, when the operation takes place normally, the invention being in these figures applied to the exhaust 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 2d , the functioning of the exhaust according to the European patent EP 1,122,617 is fully valid for this embodiment of an exhaust according to the present invention. This remark also applies to the embodiment of an exhaust 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 the embodiments of an escapement according to the present invention, that is to say to any Robin type escapement, or even to any anchor escapement, having a lost shot, 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 indirect impulse means 2.6 on the second mobile 2 and a different number of teeth of the escapement 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 exhaust, since the indirect impulse means 2.6 only takes an active role when an abnormal situation occurs. Therefore, all of the above explanations in the context of the series of figures 2a to 2d are valid for the normal operation of an exhaust according to the present invention as illustrated in the series of figures 4a to 4d which show the same main phases of normal operation of an exhaust according to the present invention as the series of Figures 2a to 2d . For reasons of simplicity, these explanations will not be repeated here while they apply by analogy to the series of figures 4a to 4d .

With regard to the operation of an escapement according to the present invention when an anomaly occurs, in particular following an untimely movement or an untimely stop of the watch movement, the figure 5 illustrates by a schematic view from above a phase of operation of the exhaust according to the present invention during which the indirect impulse means 2.6 takes an active role. In fact, 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 via an indirect pulse via the second mobile 2. The indirect pulse palette 2.6 can also give an impulse to the balance when its amplitude decreases following disarming of the barrel, which one can designate as an "impulse on demand", this case not being illustrated in the figures. The present invention thus makes it possible to avoid the drawbacks of exhausts of the prior art mentioned in the introduction by proposing an exhaust which, in addition to the components of the exhaust 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 pallet mounted near the pivot axis of the anchor 2, this indirect impulse means 2.6 remaining out of contact with the escapement wheel 3 during the entire oscillation of the regulating member during normal operation of the escapement and intervening only during abnormal operation to effect an indirect impulse.

In this context, we can add that, about fifty years ago, by making observations with a high-speed camera, watchmakers were surprised to observe that during the operation of the anchor escapement, after its released by the balance wheel, the escape wheel travels a substantial path before one of its teeth catches one of the pallets of the anchor. In fact, almost a third of the length of the input and output pallets of a conventional anchor is not used because the corresponding tooth of the escape wheel has not yet managed to make contact. This is also the case for direct impulse escapements where the teeth of the escapement wheel must catch up with the impulse pallet located on the large balance plate in order to perform a direct impulse. In both cases, this is generally considered a defect and various means are used to minimize it. An escapement according to the present invention having a pallet of indirect impulse on the anchor which is not at all caught by the teeth of the escapement wheel during normal operation of the escapement, i.e. -tell who does not participate at all in the normal functioning of the escapement, but who intervenes only during abnormal operation, is therefore in a certain way contrary to traditional technical instruction in the field of watchmaking . On the other hand, in the event of loss of amplitude, shock, or tendency to stop the escapement, one of the teeth of the escapement wheel comes into contact with the indirect impulse paddle and makes it possible to carry out an indirect impulse, which leads if necessary to automatic restarting, since the presence of the paddle of indirect impulse 2.6 brings an additional geometrical constraint which is exploited during a specific phase of the functioning of the exhaust and whose geometry can be adapted according to the needs according to the case of concrete application, for example by variation of the '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 escapement with double radial impulse mentioned in the introduction, since the third impulse pallet L positioned centrally on the anchor of this exhaust, as visible on the figure 1e , systematically transmits a torque to the balance at each half-phase of the oscillation of the regulating member during which the escapement wheel does not transmit torque to the regulating member by means of a direct pulse, it that is, this third impulse palette always participates in the normal operation of the escapement with double radial impulse. Consequently, the present invention can also be implemented in an escapement of the type with double radial impulse or in the coaxial escapement mentioned in the introduction by replacing the third palette of impulses present in and always participating in the normal operation of these exhausts by an indirect pulse pallet 2.6 according to the present invention which only intervenes during an abnormal operation of the exhaust.

In view of the arrangement and operation of a timepiece 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 anchor escapement having a lost shot, 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, those skilled in the art also understand that the present invention relates not only to such an escapement, but also to a timepiece movement comprising an energy source, a regulating member, a 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 timepiece escapement, respectively such a timepiece 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 timepiece escapement according to the present invention then makes it possible to obviate the problem of the self-starting of escapements with a lost shot, since its palette of indirect impulse comes into contact, for example following an untimely movement or a stop. nuisance of the watch movement and during the half-phase of the pendulum oscillation during which the escapement wheel does not transmit torque to the pendulum by means of a direct impulse, with the escapement wheel and transmits by via an indirect impulse via the anchor a torque on the balance wheel which is sufficient to restart the watch movement. Simultaneously, the present invention allows, in case of application to the exhaust according to the European patent EP 1,122,617 and that 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 on the second mobile 2 crosses the notch 1.2.1.3 of said skirt 1.2.1 of the first mobile 1, so that the notch 1.2.1.3 in the skirt 1.2.1 can be enlarged. Thus, the tolerances of the parts involved when the finger of the dart leaves the outside of 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 the alternative, a role of securing means.

In short, the present invention makes it possible to produce a timepiece escapement which has the advantages of a detent escapement mentioned above and whose self-starting in the event of untimely stopping of the movement is ensured, so that it does not does not present the problem of auto-starting of exhaust blowback. 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 of the stinger comes out outside of the skirt and thus avoiding constellations where a collision between said finger and said skirt of the locking device can occur. Furthermore, the proposed construction, consisting mainly of the integration of an indirect impulse palette, is simple and robust as well as reliable during the operation of the exhaust. Such an indirect pulse palette can be integrated into several types of detent and / or anchor escapements, so that the invention can be applied flexibly to several types of timepieces. In particular, the invention can be applied, preferably, in mechanical wrist watches, in particular in wrist watches fitted with a chronograph or split-seconds mechanism.

Claims (15)

Watch detent escapement capable of being integrated into a watch movement and arranged to transmit a torque coming from an energy source of said watch movement to an oscillating regulating member of said watch movement, the watch movement regulating member comprising a first mobile ( 1) and the exhaust comprising a second mobile (2) and an escape wheel (3), said first mobile (1) cooperating with said second mobile (2) 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 said second mobile (2) comes to bear, said escape wheel (3) being arranged so as to transmit, during a half-phase of each oscillation of the regulating member, a torque to said regulating member by means of a direct pulse, characterized in that said second mobile (2) comprises a means in indirect impulse (2.6) arranged and positioned so as to be, throughout the oscillation of the regulating member during normal operation of the exhaust, out of contact with the escape wheel (3), while being likely to come into contact, during the other half-phase of each oscillation of the regulating member during which the escape wheel (3) does not transmit torque to the regulating member via a direct impulse, with the escape wheel (3), in order to transmit a torque to said watch movement regulating member by means of an indirect impulse, via the second mobile (2), following an untimely movement or a untimely stopping of the watch movement. Watch escapement according to the preceding claim, characterized in that said energy source is formed by a barrel spring and that said regulating member is formed by a pendulum. Watch escapement according to the preceding claim, characterized in that said first mobile (1) of the regulating member of the watch movement is formed by a plate (1.2) carried by an axis (1.1) of the balance. Watch escapement according to one of the preceding claims, characterized in that said second mobile (2) of the escapement is provided with an angular movement or with a rectilinear movement. Watch escapement according to the preceding claims 3 and 4, characterized in that said second mobile (2) of the escapement is formed by an anchor (2), said plate (1.2) being able to cooperate with said anchor (2). Watch escapement according to one of the preceding claims, characterized in that said indirect impulse means is formed by an indirect impulse paddle (2.6) located substantially near the pivot axis of said second mobile (2), respectively of said anchor (2), in particular by an indirect impulse pallet (2.6) located on the first half, near said pivot axis, of the anchor arm (2) carrying the output rest pallet (2.5). Watch escapement according to the preceding claim, characterized in that the said indirect impulse paddle (2.6) is made of a material of low friction and of low wear, preferably in ruby or sapphire. Clock escapement according to one of the preceding claims 5 to 7, characterized in that the said escapement wheel (3) has a number of teeth situated in the range from 13 to 19. Watch escapement according to one of the preceding claims 3 to 8, characterized in that the first mobile (1) formed by said plate (1.2) comprises a circular plate 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) being immobilized in the first position when it is in abutment 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 being immobilized in the second position when it is in abutment on the second stop (4.2) and when its finger (2.2.3) adjoins the external wall (1.2.1.2) of said skirt (1.2.1). Clock escapement according to the preceding claim, characterized in that said second mobile (2) comprises at least one securing and guiding surface oriented in a direction substantially opposite to said finger (2.2.3) in order to secure said second mobile (2) during the exhaust operating phase during which the finger (2.2.3) fixed on the second mobile (2) crosses the notch (1.2.1.3) of said skirt (1.2.1) of the first mobile (1) . Device according to the preceding claim, characterized in that the said safety and guiding surface is arranged and positioned so as to be, during the impulse phase of the balance wheel (1) by the escape wheel (3), in outer 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 (2), respectively the anchor (2), preventing it from returning, following an untimely movement, on the trajectory of the escape wheel (3). Timepiece escapement according to one of the preceding claims, characterized in that it is a direct impulse escapement comprising an escape wheel (3) transmitting the impulse directly to the balance (1), preferably d '' a Robin type exhaust. Watch movement comprising an energy source, a regulating member (1), an escapement and a gear train, characterized in that the escapement is a watch escapement according to one of the preceding claims 1 to 12. Timepiece, preferably wristwatch, characterized in that it comprises a timepiece escapement according to one of the preceding claims 1 to 12, respectively a timepiece movement according to the preceding claim. Timepiece according to the preceding claim, characterized in that it is a chronograph or split-seconds watch.

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