EP2553532A1

EP2553532A1 - Escapement for a timepiece, with impact protection

Info

Publication number: EP2553532A1
Application number: EP11719639A
Authority: EP
Inventors: Anthony Krüttli
Original assignee: Patek Philippe SA Geneve
Current assignee: Patek Philippe SA Geneve
Priority date: 2010-04-01
Filing date: 2011-03-31
Publication date: 2013-02-06
Anticipated expiration: 2031-03-31
Also published as: SG183413A1; US8757869B2; WO2011121432A1; US20120307601A1; CH702930A2; EP2553532B1; JP2013524201A; JP5735630B2

Abstract

The invention relates to an escapement comprising an escape wheel (1) and a pallet (2). On the pallet (2) and/or the escape wheel (1), instead of the traditional banking or pins, the escapement comprises means (17, 18) for limiting the oscillations of the pallet (2) during the normal operation of the escapement. In order to prevent contact between the striking tip (10) of the pallet stones (6, 7) and the escape wheel (1) in the event of an impact, the escape wheel (1) comprises projections (20, 21, 22) along the periphery thereof.

Description

Clock escapement with shock protection

The present invention relates to an anchor clock escapement, such as a Swiss lever escapement.

Anchor escapements generally include fixed limiting members, in the form of walls called "étocaux" machined in the plate or in a bridge, or in the form of pins fixed to the plate. These fixed limiting members serve as abutments to the anchor to limit the amplitude of its oscillations and define two rest positions where the anchor bears respectively against one of these fixed limiting members while a tooth of the escape wheel is itself bearing against the rest plane of the pallet entry or exit of the anchor. These fixed limitation members also play a role of protection of the escapement against impacts, in that they prevent the anchor from moving beyond its rest positions during shocks to the watch and thereby prevent the pallets of the anchor can hit the escape wheel.

However, anchor escapements do not include such fixed limiting members. In this case, it is a particular form or arrangement of the toothing of the escape wheel and / or the paddles which fulfills the function of limiting the oscillations of the anchor during normal operation of the escapement. that is to say which defines the rest positions of the anchor. Examples of such exhausts are described in documents CH 101651, CH 569997, CH 343898, DE 1162290, GB 682566 and US 3146581. With the exception of that described in document CH 569997, these exhausts all have the disadvantage that, during shocks to the watch, the anchor can move beyond its rest positions until the pulse tip of one of the pallets strikes the escape wheel. By way of illustration, FIG. 1 shows the position of an anchor escapement without fixed members of limitation after an impact having displaced the anchor in the direction indicated by the arrow F1 while the anchor was in its rest position where its entry pallet blocked the escape wheel. It can be seen that the impulse spout of the entry pallet is in contact with the serge of the escape wheel. Similarly, during an impact having the effect of moving the anchor in the opposite direction (FIG. 2, arrow F2), the impulse spout of the output pallet comes into contact with the wheel serge. exhaust. Such contacts between a ridge (the impulse spout) and the escape wheel can create significant damage to the anchor and / or the escape wheel, particularly if these elements, or any of between them, are made of a fragile material such as silicon. In addition, any resulting chips may move in the movement of the watch, cause damage to other components and disrupt the movement.

The exhaust according to document CH 569997 has dihedral recesses formed in the serge of the escape wheel, recesses for receiving and locking the pallets in the rest positions of the anchor. In case of shock suffered by the watch, these recesses prevent the anchor from moving beyond its rest positions. In some embodiments, small clearances are further provided in the escape wheel to prevent the impulse tip of the vanes from contacting said wheel in said home positions. This escapement nevertheless has a major disadvantage in that it requires that the pallets have the same shape and identical drafting angles, which makes it impossible to optimize the efficiency of the exhaust by varying the shapes and dimensions of the pallets .

The present invention aims to overcome the aforementioned drawbacks and proposes for this purpose a clockwork escapement comprising an escape wheel and an anchor, the anchor comprising an entry pallet and an output pallet cooperating with the teeth of the wheel. each of the entry and exit pallets comprising a reverse, an impulse spout, an impulse face and a rest face, the anchor and / or the escape wheel comprising means for limiting oscillations of the anchor in operation normal escape to a range of movement delimited by an entry rest position where the entry pallet blocks the escape wheel and by an exit rest position where the output pallet blocks the escape wheel , characterized in that the escape wheel comprises at its periphery projections arranged so that:

during a shock having the effect of moving the anchor out of said movement range in a first direction, the impulse face and the reverse of the entry pallet can come to bear respectively on two of the projections and stop thus the anchor, without contact between the impulse spout of the entry pallet and the escape wheel,

and / or so that:

during a shock having the effect of moving the anchor out of said displacement range in a second direction, the impulse face and the reverse of the output pallet can come to bear respectively on two of the projections and stop and the anchor, without contact between the pulse tip of the output pallet and the escape wheel.

The projections may comprise first protrusions located between the teeth of the escape wheel and may each serve as a support for the impulse face of the entry pallet in the event of an impact having the effect of causing the anchor to said range of movement in the first direction and the back of the output pallet in case of impact causing the anchor to move out of said range of displacement in the second direction.

The projections may also include second projections located on the rear flanks of the teeth of the escape wheel or between said teeth and may each serve as a support on the reverse side of the entry pallet in the event of an impact having the effect of the anchor of said moving range in the first direction.

The projections may also include third projections located on the leading flanks of the teeth of the escape wheel or between said teeth and each of which can be used to support the impulse face of the output pallet when the impact has the effect of moving the anchor out of said range of displacement in the second direction.

The projections are preferably rounded.

Said means for limiting the oscillations of the anchor may comprise a wedge defined by the rest face of the input pallet and / or the output pallet and with which can cooperate a spur of the teeth of the escape wheel .

Preferably, the wedge is defined by a return plane and a rest plane formed on the rest face of the input pallet and / or the output pallet, and the projections are arranged so that:

after an impact having had the effect of causing the anchor to come out of said displacement range in the first direction until said stop of the anchor, one of said two projections can push the anchor towards its rest position of entry until a cooperation between the idler of a tooth of the escape wheel and the return plane of the entry pallet finishes to return the anchor to its rest position of entry, under the action of the rotation of the escape wheel;

and / or so that:

after an impact having had the effect of bringing the anchor out of said range of displacement in the second direction until said stop of the anchor, one of said two projections can push the anchor towards its resting position of exit until a cooperation between the idler of a tooth of the escape wheel and the return plane of the output pallet ends to return the anchor to its rest position of exit, under the action of the rotation of the escape wheel.

The anchor and the escape wheel can each be made in one piece. In particular embodiments, at least one of the anchor and escapement wheel is made of a brittle material, such as glass, diamond, silicon, silicon carbide, oxide crystallized aluminum or other material based on any of these materials.

In one embodiment, the anchor includes a fork including a fork inlet and horns, and the inner face of each horn is rounded to soften the transition between that inner face and the corresponding inner face of the inlet of the horn. fork.

In another embodiment, the escapement comprises a transmission member between the anchor and a balance shaft, this member comprises a part fulfilling the function of a plateau pin, said part comprises convex active surfaces and a surface inactive connecting the active surfaces to each other, and the inactive surface is convex with a radius of curvature greater than that of the active surfaces so as to soften the transition between the inactive surface and each of the active surfaces. Preferably, said member is a one-piece piece comprising an opening for mounting it on the balance shaft and a radially extending pin constituting said part fulfilling the function of a plateau pin.

The escapement according to the invention is typically a Swiss lever escapement.

The present invention also provides a watch exhaust anchor comprising a fork comprising a fork inlet and horns, characterized in that the inner face of each horn is rounded so as to soften the transition between this inner face and the face corresponding internal entry of the fork entry.

The present invention further provides a transmission member between a clock anchor and a clock balance shaft, comprising a portion performing the function of a plate pin, said portion comprising convex active surfaces and an inactive surface connecting active surfaces between characterized in that the inactive surface is convex with a greater radius of curvature than that of the active surfaces so as to soften the transition between the inactive surface and each of the active surfaces.

The invention also relates to a timepiece, such as a wristwatch, comprising an escapement, an anchor or a transmission member as defined above.

Other features and advantages of the present invention will appear on reading the following detailed description given with reference to the accompanying drawings in which:

FIG. 1, already commented on, shows in plan view a known type of escapement receiving a shock having the effect of moving the anchor out of its normal range of movement in a first direction; Figure 2, already commented, shows the same escapement receiving a shock having the effect of the anchor out of its normal range of movement in a second direction opposite to the first direction; FIGS. 3 and 4 show an escapement according to a first embodiment of the invention with its anchor situated respectively in its entry rest position, where the entry pallet of the anchor blocks the escape wheel, and in its resting position of exit, where it is the pallet of exit of the anchor which blocks the escape wheel; FIG. 5 shows an intermediate position of the escapement according to the first embodiment of the invention during an impact having the effect of moving the anchor out of its normal range of movement in a first direction;

FIG. 6 shows the final position of the escapement according to the first embodiment of the invention during an impact such as that defined in relation with FIG. 5;

FIG. 7 shows an intermediate position of the escapement according to the first embodiment of the invention during an impact having for effect of moving the anchor out of its normal displacement range in a second direction opposite to the first direction;

FIG. 8 shows the final position of the escapement according to the first embodiment of the invention during an impact such as that defined in relation with FIG. 7;

FIGS. 9 and 10 show an escapement according to a second embodiment of the invention with its anchor respectively situated in its rest position of entry, where the entry pallet of the anchor blocks the escape wheel, and in its resting position of exit, where it is the pallet of exit of the anchor which blocks the escape wheel;

FIG. 11 shows an intermediate position of the escapement according to the second embodiment of the invention during an impact having the effect of moving the anchor out of its normal range of movement in a first direction;

FIG. 12 shows the final position of the escapement according to the second embodiment of the invention during an impact such as that defined in relation with FIG. 11;

FIG. 13 shows an intermediate position of the escapement according to the second embodiment of the invention during an impact having the effect of moving the anchor out of its normal range of displacement in a second direction opposite to the first direction;

FIG. 14 shows the final position of the escapement according to the second embodiment of the invention during an impact such as that defined in relation with FIG. 13;

Figure 15 shows in top view a portion of an exhaust according to a third embodiment of the invention;

Figure 16 shows in top view a portion of an exhaust according to a fourth embodiment of the invention. With reference to FIG. 3, an escapement according to a first embodiment of the invention for a timepiece such as a wristwatch comprises an escape wheel 1, an anchor 2 and, mounted on an axis of balance 3, a transmission member between the anchor 2 and the balance shaft 3 constituted for example by large and small trays 4, 5. As in a traditional Swiss anchor escapement, the anchor 2 is pivotally mounted on a 2a axis and comprises an input pallet 6 and an output pallet 7 cooperating with the teeth 8 of the escape wheel 1, each of these pallets 6, 7 comprising a cuff 9, a pulse nozzle 10, a face 11 and a rest face 12. The anchor 2 also comprises at the end of its rod 13 a fork comprising a fork entry 14a cooperating with a plateau pin or "ellipse" 15 integral with the large plate 4, horns 14b and a member 16 performing the function of a sting and cooperating with the small plate 5. The operation of the exhaust is thus identical to that of a traditional Swiss lever escapement.

The function of limiting the oscillations of the anchor 2 during normal operation of the escapement is ensured not by fixed probes or pins but by a particular form of the entry and exit pallets 6, 7 of the anchor 2. Thus, these pallets 6, 7 comprise on their rest face 12 a rest plane 17 and a return plane 18 forming an angle between them. The stop of the anchor 2 in its entry rest position, where its entry pallet 6 blocks the escape wheel 1, occurs when the spout 19 of a tooth 8 of the wheel of Exhaust 1 is housed in the corner defined by the rest plane 17 and the return plane 18 of the input pallet 6 (Figure 3). The stop of the anchor 2 in its exit rest position, where its output pallet 7 blocks the escape wheel 1, occurs when the quill 19 of a tooth 8 of the escape wheel 1 is housed in the corner defined by the rest plane 17 and the return plane 18 of the output pallet 7 (Figure 4). According to the invention, the escape wheel 1 has at its periphery protection formations against shocks, namely, in this first embodiment:

first projections 20 regularly distributed angularly and formed on the serge of the wheel 1, between the teeth 8;

second projections 21 regularly distributed angularly and formed on the rear flank of the teeth 8;

third projections 22 regularly distributed angularly and formed on the front flank of the teeth 8.

The concepts of "front" and "rear" must be understood in the context of the present invention with respect to the direction of rotation, designated R, of the wheel 1 when it is moving by the action of the driving member (barrel) of the timepiece. The second and third protrusions 21, 22 give a convex shape to the rear and front flanks of the teeth 8. The first projections 20 are shaped waves moving in the opposite direction of the direction R. The projections 20, 21, 22 are all rounded. Between each first projection 20 and the second projection 21 which is consecutive in the direction R is provided a first clearance 23. Between each first projection 20 and the third projection 22 which is consecutive thereto in the direction opposite to the direction R is provided a second clearance 24.

As shown in FIGS. 5 and 6, during an impact occurring while the anchor 2 was in its resting entry position and having the effect of angularly displacing the anchor 2 in the direction indicated by the arrow F3, that is to say to get the anchor 2 out of its normal range of movement delimited by its entry and exit rest positions, the entry pallet 6 is moving towards the serge of the wheel 1, this which causes the wheel 1 to move back by the cooperation between the rest spoiler 19 of a tooth 8 and the return plane 18 of the entry pallet 6, and the impulse face 11 of the entry pallet 6 enters into position. contact with a projection 20 (Figure 5). The shape of the projection 20 allows this movement to continue, the impulse face 11 sliding on the projection 20 thus further rolling back the wheel 1 until the reverse 9 of the input pallet 6 abuts against a projection 21 (Figure 6). At this moment, the impulse face 11 exerts on the projection 20 a force tending to turn the wheel 1 in the direction opposite to the direction R while the notch 9 exerts on the projection 21 a force tending to turn the wheel 1 in the direction R. The wheel 1 and the anchor 2 are thus stopped. During all the movement caused by the impact, the pulse tip 10 of the entry pallet 6 remains out of contact with the wheel 1. In the final stop position illustrated in FIG. of the entry pallet 6 is in the clearance 23. Once the effect of the shock is over, the anchor 2 is returned to its input rest position by the projection 20 pushing and sliding on the impulse plane 11 then by the spout 19 of a tooth 8 pushing and sliding on the return plane 18, under the action of the drive member driving the escape wheel 1 in the direction R.

As shown in FIGS. 7 and 8, during an impact occurring while the anchor 2 was in its exit rest position and having the effect of angularly displacing the anchor 2 in the direction indicated by the arrow F4, c that is to say to get the anchor 2 out of its normal range of movement delimited by its entry and exit rest positions, the output pallet 7 is moving towards the serge of the wheel 1, which makes back the wheel 1 by the cooperation between the spout 19 of a tooth 8 and the return plane 18 of the output pallet 7, and the impeller face 11 of the output pallet 7 comes into contact with a protrusion 22 (Figure 7). The shape of the projection 22 allows this movement to continue, the impulse face 11 sliding on the projection 22 thus further backing the wheel 1 until the reverse 9 of the output pallet 7 abuts against a protrusion 20 (Figure 8). At this moment, the impulse face 11 exerts on the projection 22 a force tending to turn the wheel 1 in the direction opposite to the direction R while the notch 9 exerts on the projection 20 a force tending to turn the wheel 1 in the direction R. The wheel 1 and the anchor 2 are thus stopped. During all the movement caused by the impact, the pulse tip 10 of the output pallet 7 remains out of contact with the wheel 1. In the final stop position illustrated in FIG. the palette of Exit 7 is in the clearance 24. Once the effect of the shock is over, the anchor 2 is returned to its resting position by the projection 22 pushing and sliding on the pulse plane 11 and then by the spout. rest 19 of a tooth 8 pushing and sliding on the return plane 18, under the action of the drive member driving the escape wheel 1 in the direction R.

In this way, during such shocks, the escapement is protected from any contact between the pulse tip 10 of the vanes 6, 7 and the wheel 1. This result is achieved without it being necessary to impose an arrangement, a shape or dimensions particular to the vanes 6, 7, the projections 20, 21, 22 playing no role during the normal operation of the exhaust. Thus, during the design of the exhaust, the vanes 6, 7 can be shaped and sized to optimize the efficiency of the exhaust, for example as described in the patent application EP 1892589 of the present applicant, then the projections 20 , 21, 22 can be drawn according to the shape and dimensions of the pallets 6, 7.

When the shocks described above occur while the anchor 2 is moving between its two rest positions, with the plateau pin 15 in the fork inlet 14a or between the horns 14b, the shock will firstly effect of moving the anchor 2 to one of its rest positions and, if the force of the impact is greater than the holding force of the anchor 2 in this rest position, to move the anchor 2 to beyond this rest position. The projections 20, 21, 22 then play the role described above.

When an impact occurs bringing the anchor 2 closer to one of its rest positions while the anchor 2 was in its other rest position, that is to say to move the anchor 2 in the direction F4 while it was in its position of rest of entry or in the direction F3 while it was in its position of rest of exit, the organ 16 fulfilling the function of the dart abuts against the small plate 5 which limits the movement of the anchor 2. The present invention is of particular interest in the case of escapements made in a brittle material, that is to say a material not having a plastic field, such as glass, diamond, silicon, silicon carbide , crystallized aluminum oxide or other materials based on any of these materials. By avoiding any contact between the impulse tip 10 of the vanes 6, 7 and the escape wheel 1 during an impact, the strong constraints inherent to the contacts between edges and surfaces are avoided, constraints which are incompatible with the fragility of an such matter. It should also be noted in this respect that the rounded shape of the projections 20, 21, 22 contributes to reducing the stresses created by the contacts between the vanes 6, 7 and the escape wheel 1.

Thus, the escape wheel 1 and the anchor 2, or one of them, can be produced in such a fragile material, in a monolithic manner, for example by deep reactive ion etching (DRIE). .

A second embodiment of the invention is illustrated in Figures 9 to 14. The exhaust according to this second embodiment is identical to that according to the first embodiment, with the exception of the shape of the projections 20 ', 21 ', 22' of the escape wheel and the location of the second projections 21 ', located in part at least on the serge of said wheel and no longer entirely on the trailing edge of the teeth of said wheel. Alternatively, the third projections 22 ', located on the front flank of the teeth of the escape wheel, could be separated from said teeth and be also on the serge of said wheel.

Although it is preferable that the means for limiting the oscillations of the anchor during normal operation of the escapement are provided on the anchor and / or the escape wheel for both the entry and the exit, the The present invention does not exclude the use of a fixed limiting member, for example of the pin type, for the entry or exit and of the limiting means provided on the anchor and / or the escape wheel for the exit or entry, respectively. In this case, the projections of the escape wheel would of course be useful only on the side, entry or exit, where said limitation means would be. Furthermore, the present invention can be applied to escapements whose escapement wheel is constituted not of a board as shown but of two superposed boards cooperating respectively with the entry and exit pallets, as described in FIG. Patent Application EP 1914605. In this case, each of the two boards may include projections for the pallet with which it cooperates.

It has also been found by the present inventor that significant damage may result from shocks between the fork anchor fork and the plateau pin, particularly if these, or any of them, are made in a fragile material. As shown in FIG. 3, the transition between the inner face of each horn 14b and the corresponding inner face of the fork inlet 14a is constituted by a ridge 14c. During an impact on the watch, the plateau pin 15 may hit or be struck by one of these edges 14c. Depending on the materials used, such a collision may damage the area of the edge 14c and / or the plateau pin 15, or even break the edge 14c and produce chips that will be free to move in movement and disrupt the operation. FIG. 15 shows an embodiment of the invention in which the internal faces 25 of the horns 26 of the anchor are rounded (convex) in order to ensure a smooth transition without edges, in other words a transition with a large radius of curvature, between these inner faces 25 and the corresponding inner faces 27 of the fork inlet 28. Thus, in case of impact, the contact pressures and therefore the risk of damage are reduced. The anchor is typically made of a fragile material such as glass, diamond, silicon, silicon carbide, crystallized aluminum oxide or another material based on one of these materials, and machined by deep reactive ion etching.

In a comparable manner, it can be seen in FIG. 3 that the plate pin 15, when it has the traditional shape of a half-cylinder or segment of a cylinder, as shown, has edges 15a between its cylindrical surface 15b and its flat surface 15c. During an impact suffered by the watch, one of these ridges 15a can hit or be struck by the fork of the anchor. Depending on the materials used, such a strike may damage the area of the edge 15a and / or the fork of the anchor, or even break the edge 15a and produce chippings that will be free to move in the movement and to disrupt the operation. FIG. 16 shows another embodiment of the invention, combinable with that of FIG. 15, in which the plate pin is constituted by a lug 29 of a one-piece part 30 fulfilling the function of transmission member between the anchor and the balance shaft. The one-piece piece 30 comprises an opening 31 for its mounting on the balance shaft. The one-piece piece 30 is typically made of a fragile material such as glass, diamond, silicon, silicon carbide, crystallized aluminum oxide or another material based on one of these materials, and machined by deep reactive ion etching. The lug 29 projects radially on the periphery of an annular portion 32 of the part 30 having the opening 31. The lug 29 has two opposite convex lateral surfaces 33 in the form of segments of the same cylinder. These two surfaces 33 are the active surfaces of the lug 29, which come into contact and cooperate with the fork of the anchor during the normal operation of the exhaust, in the same manner as the cylindrical surface 15b of the dowel 15. The end of the lug 29 is formed by a convex cylindrical surface 34 of greater radius of curvature than the surfaces 33. This surface 34 corresponds to the flat surface 15c of the plateau pin 15, and is inactive at this point. meaning that it is not intended to come into contact with the fork of the anchor during normal operation of the escapement. Like the surface 15c, this surface 34 serves to define the safety of the exhaust in terms of horn and corner frolics. In the present invention, the convexity of this surface 34 substantially rounds the transition 35 between each of the surfaces 33 and the surface 34 and thus to eliminate the ridges 15a in order to reduce the contact pressures and therefore the risks damage in case of shocks to the watch. The radius of curvature of the surface 34 is chosen to be small enough that the transitions are soft, i.e., have a large radius of curvature, and sufficiently large to maintain sufficient safety in terms of horn frolics. corner. The one-piece piece 30 may be associated with a small tray of the type designated by the reference numeral 5 in FIG. 3. It may be attached to this small plate or monoblock therewith.

Claims

A clock escapement comprising an escape wheel (1) and an anchor (2), the anchor (2) comprising an entry pallet (6) and an output pallet (7) cooperating with teeth ( 8) of the escape wheel (1), each of the entry and exit pallets (6, 7) comprising a cuff (9), a pulse nozzle (10), a pulse face (11) and a rest face (12), the anchor (2) and / or the escape wheel (1) comprising means (17, 18) for limiting the oscillations of the anchor (2) during normal operation of the exhaust to a range of travel delimited by an entry rest position where the entry pallet (6) blocks the escape wheel (1) and by an exit rest position where the exit pallet (7) blocks the escape wheel (1), characterized in that the escape wheel (1) comprises at its periphery projections (20, 21, 22) arranged so that:

during an impact causing the anchor (2) to move out of said movement range in a first direction (F3), the impulse face (11) and the reverse (9) of the entry pallet (6) can respectively abut two (20, 21) protrusions (20, 21, 22) and stop the anchor (2), without contact between the pulse tip (10) of the pallet inlet (6) and the escape wheel (1),

and / or so that:

during an impact causing the anchor (2) to move out of said displacement range in a second direction (F4), the impulse face (11) and the cuff (9) of the output pallet ( 7) can respectively abut two (22, 20) projections (20, 21, 22) and stop the anchor (2), without contact between the beak pulse (10) of the output pallet (7) and the escape wheel (1).

2. Exhaust according to claim 1, characterized in that said projections (20, 21, 22) comprise first projections (20) located between the teeth (8) of the escape wheel (1) and can each serve as pressing the impulse face (11) of the entry pallet (6) in the event of an impact causing the anchor (2) to come out of said displacement range in the first direction (F3) and on the reverse side (9) of the output pallet (7) in the event of impact causing the anchor (2) to move out of said displacement range in the second direction (F4).

3. Exhaust according to claim 1 or 2, characterized in that said projections (20, 21, 22) comprise second projections (21) located on the rear flanks of the teeth (8) of the escape wheel (1) or between said teeth (8) and each of which can serve as a support for the cuff (9) of the entry pallet (6) in the event of an impact causing the anchor (2) to move out of said movement range into the first sense (F3).

4. Exhaust according to any one of claims 1 to 3, characterized in that said projections (20, 21, 22) comprise third projections (22) located on the front flanks of the teeth (8) of the escape wheel (1) or between said teeth (8) and can each serve as a support for the impulse face (11) of the output pallet (7) in the event of an impact causing the anchor to come out (2) of said displacement range in the second direction (F4).

5. Exhaust according to any one of claims 1 to 4, characterized in that said projections (20, 21, 22) are rounded.

6. Exhaust according to any one of claims 1 to 5, characterized in that said means for limiting the oscillations of the anchor (2) comprise a corner defined by the rest face (12) of the entry pallet and / or the output pallet (6, 7) and with which can cooperate a spur (19) teeth (8) of the escape wheel (1).

7. Exhaust according to claim 6, characterized in that the wedge is defined by a return plane (18) and by a rest plane (17) formed on the face of rest (12) of the entry pallet and / or the output pallet (6, 7), and in that said projections (20, 21, 22) are arranged so that:

after an impact having caused the anchor (2) to leave said displacement range in the first direction (F3) until said stop of the anchor (2), one (20) of said two projections (20, 21) can push the anchor (2) towards its rest position of entry until a cooperation between the spout (19) of a tooth (8) of the escape wheel (1) and the return plane (18) of the entry pallet (6) ends to return the anchor (2) to its input rest position, under the action of the rotation of the wheel of exhaust (1);

and / or so that:

after an impact having caused the anchor (2) to move out of said movement range in the second direction (F4) until said stop of the anchor (2), one (22) of said two projections (22, 20) can push the anchor (2) to its resting position of exit until a cooperation between the nose (19) of a tooth (8) of the escape wheel (1) and the return plane (18) of the output pallet (7) finishes bringing the anchor (2) back to its exit rest position, under the action of the rotation of the wheel exhaust (1).

8. Exhaust according to any one of claims 1 to 7, characterized in that the escape wheel (1) is in one piece.

9. Exhaust according to any one of claims 1 to 8, characterized in that the anchor (2) is in one piece.

10. Exhaust according to any one of claims 1 to 9, characterized in that at least one of the anchor (2) and the escape wheel (1) is made of a brittle material.

11. Exhaust according to claim 10, characterized in that said fragile material is glass, diamond, silicon, silicon carbide, crystallized aluminum oxide or another material based on one of these materials. .

Exhaust according to any one of claims 1 to 11, characterized in that the anchor comprises a fork comprising a fork inlet (28) and horns (26), and that the inner face (25) of each horn (26) is rounded to soften the transition between that inner face (25) and the corresponding inner face (27) of the fork inlet (28).

13. Exhaust according to any one of claims 1 to 12, characterized in that it comprises a member (30) for transmission between the anchor and a balance shaft, in that this member (30) comprises a portion (29) performing the function of a plateau pin (15), in that said portion (29) comprises convex active surfaces (33) and an inactive surface (34) connecting the active surfaces (33) to each other, and in that the inactive surface (34) is convex with a greater radius of curvature than that of the active surfaces (33) so as to soften the transition (35) between the inactive surface (34) and each of the active surfaces (34). ).

14. Exhaust according to claim 13, characterized in that said member (30) is a single piece comprising an opening (31) for mounting on the balance shaft and a lug (29) extending radially and constituting said portion. (29) performing the function of a plateau pin (15).

15. Exhaust according to any one of claims 1 to 14, characterized in that it consists of a Swiss lever escapement.

16. Watch exhaust anchor comprising a fork comprising a fork inlet (28) and horns (26), characterized in that the inner face (25) of each horn (26) is rounded so as to soften the transition between this inner face (25) and the corresponding inner face (27) of the fork inlet (28).

17. A transmission member (30) between a watch anchor and a watch balance pin, comprising a portion (29) fulfilling the function of a plateau pin (15), said portion (29) comprising surfaces convex active elements (33) and an inactive surface (34) connecting the active surfaces (33) to one another, characterized in that the inactive surface (34) is convex with a greater radius of curvature than that of the active surfaces (33) so as to soften the transition (35) between the inactive surface (34) and each of the active surfaces (34).

18. Timepiece comprising an escapement according to any one of claims 1 to 15, an anchor according to claim 16 or a transmission member according to claim 17.