CH701921A2 - Lever escapement mechanism for watch, has gears connected to escapement wheels that are arranged with pallets in alternate way, body swiveled on support around axis, and anchor provided with pallet - Google Patents

Abstract

The mechanism has an escapement wheel (2) and another escapement wheel (3) connected to a finishing wheel. An anchor (4) is provided with a pallet (22) and another pallet (24) that are arranged to cooperate with the escapement wheels. A fork (6) is arranged to cooperate with beam plate (10). Gears are connected to the escapement wheels that are arranged with the pallets in an alternate way. A body (12) is swiveled on a support (14) around an axis (15). A structure (16) is formed on the body that includes the fork.

Description

Technical area

The present invention relates to an anchor escapement for a timepiece comprising: a first and a second escape wheel intended to be kinematically connected to a finishing gear train, said exhaust wheels being arranged so as not to mesh with each other, an anchor provided with a first and a second pallet arranged to cooperate with respectively said first and second escape wheels, and a fork arranged to cooperate with a balance plate in order to supply it with energy .

The present invention also relates to a timepiece comprising such an escapement anchor. State of the art

[0003] In the field of watchmaking, there are known escape mechanisms whose purpose is to maintain and count the oscillations of the pendulum of a watch. The most used is the Swiss lever escapement, whose escapement consists of a single wheel. Other solutions are constantly sought to improve the performance of the exhaust mechanisms.

In particular, numerous documents describe exhaust mechanisms comprising two escape mobiles. For example, patents GB 114 295 or GB 390 275 describe exhaust systems comprising two concentric exhaust wheels, rotating in the same direction.

Patent applications EP 1 367 462 or EP 1 221 637 describe escapements with two escape wheels rotating in the opposite direction but meshing with each other and each cooperating with an anchor of particular shape, of which the construction is relatively complex.

The patent application EP 1 983 390 describes an escapement anchor comprising two movable exhaust, driven by a first and a second wheel. The balance plate carries an ankle, a first impulse pallet arranged to cooperate with the teeth carried by the first mobile, and a third impulse pallet arranged to cooperate with the teeth on the second mobile. The anchor is articulated on a pivot and is provided with a fork cooperating with the plateau pin, a second pulse pallet arranged to cooperate with the teeth of the first mobile, and first and second pallets arranged to cooperating with the teeth of said first mobile, a fourth impulse pallet arranged to cooperate with the teeth of the second mobile, and third and fourth pallets arranged to cooperate with the teeth of said second mobile.

This escape mechanism generates pulses which are double since they come simultaneously from the two escape mobiles.

However, such a mechanism is of complicated construction.

The present invention aims to provide an exhaust mechanism without the disadvantages above and to improve the performance of the exhaust.

Disclosure of the invention

For this purpose, and in accordance with the present invention, there is provided an anchor escapement for a timepiece comprising: a first and a second escape wheel intended to be kinematically connected to a finishing gear train, said exhaust wheels being arranged so as not to mesh with each other, an anchor provided with a first and a second pallet arranged to cooperate with respectively said first and second escape wheels, and a fork arranged to cooperate with a balance plate in order to supply it with energy .

According to the invention, the escapement further comprises a gear kinematically connecting the first and second escape wheels and arranged so that said first and second exhaust wheels rotate in opposite directions. In addition, the first and second pallets are arranged to work, with respectively said first and second escape wheels, alternately.

The gear is preferably a differential gear but can also be a reference.

Advantageously, the anchor may comprise: - a support, a body pivotally mounted on said support about an axis, said body comprising the fork, a structure mounted articulated on said body, arranged to move in translation relative to said support, and having two ends respectively carrying the first and second pallets.

According to a first embodiment, the first and second escape wheels are separated and said support is arranged to be pivotally mounted on a frame of the timepiece. The structure comprises a single arm having in its center a finger articulated in the body of the anchor and carrying a pallet at each of its ends, said arm being arranged to move relative to the support in a translational movement perpendicular to the longitudinal axis of the anchor.

According to a second embodiment, the first and second escape wheels are superimposed and concentric, and said support is arranged to be fixedly mounted on a frame of the timepiece. The structure comprises two arms each terminated at one end by a finger articulated in the body of the anchor and at the other end by a pallet, said arms being arranged to move relative to the support in a translation movement parallel to the longitudinal axis of the anchor.

Advantageously for the two embodiments, the structure comprises, at its ends respectively carrying the first and second pallets, a cutout, one of whose faces forms both the pulse plane and the plane. Rest of the pallet.

Advantageously, the fork of the anchor does not include stinger so that the balance plate is a simple plate, not having a small plate.

The present invention also proposes a timepiece comprising an exhaust as defined above.

Brief description of the drawings

Other details of the invention will appear more clearly on reading the description which follows, given with reference to the accompanying drawings in which: <tb> - figs. 1 and 2 <sep> respectively show a perspective view and a top view of a first embodiment of an exhaust mechanism according to the invention, and <tb> - figs. 3 and 4 <sep> respectively show a perspective view and a top view of a second embodiment of an exhaust mechanism according to the invention.

Embodiments of the invention

With reference to FIGS. 1 and 2, there is shown a first embodiment of an anchor escapement according to the invention.

In this variant, the exhaust 1 comprises a first escape wheel 2, a second escape wheel 3, and an anchor 4. The exhaust wheels 2 and 3 are intended to be kinematically connected to a single finishing gear (not shown) and are arranged on either side of the anchor 4 so that they do not mesh with each other. The first and second escape wheels 2 and 3 are positioned so that their teeth are offset, that is to say that, on either side of the anchor 4, a tooth of the teeth of one of the wheels is substantially at the same height as a hollow of the toothing of the other wheel.

The exhaust further comprises a differential gear or a gear (not shown) interposed between one of the exhaust wheels 2, 3 and the gear train so that when said exhaust wheels 2 and 3 turn, they turn in opposite directions. For example, the wheel 2 rotates clockwise and the wheel 3 rotates counterclockwise. The first and second exhaust wheels 2 and 3 being kinematically connected, stopping one causes stopping the other, and the rotation of one causes the rotation of the other, in opposite directions.

In a conventional manner, the anchor 4 is provided with a fork 6 arranged to cooperate with the plate pin 8 of a balance plate 10 in order to provide energy. The construction of the fork, the balance plate and its ankle are known to those skilled in the art and do not need to be described in more detail.

According to the invention, the anchor 4 comprises a body 12 pivotally mounted on a support 14 about an axis 15. The body 12 comprises a cylindrical portion of annular section, the center is crossed by the axis 15. A rod 6a, terminated by the fork 6, protrudes perpendicularly from the cylinder. The anchor 4 thus has a longitudinal axis passing through the body 12 and the rod 6a. In addition, the anchor 4 comprises a structure 16 mounted articulated on the body 12, and disposed substantially perpendicular to the rod 6a. The structure 16 is arranged to move in translation relative to the support 14. For this purpose, the structure 16 comprises a single parallelepiped-shaped arm, and having at its center a finger 18 mounted in an oblong orifice 20 provided on the body 12 and wherein the finger 18 can move. At each of its ends, the arm comprises a cut at right angles so as to form a first pallet 22 and a second pallet 24. Advantageously, as will be seen below, the horizontal surface of the cutout forms both the impulse plan and the rest plan of the pallets of the anchor.

In this embodiment, the support 14 is also pivotally mounted on a frame (not shown) of the timepiece around the axis 15. The support 14 comprises a base 26, circular in shape, having a circular housing in which can rotate the cylindrical portion of the body 12 of the anchor 4 about the axis 15. The base 26 has, opposite the rod 6a, a tail 27, arranged to abut against two pins limiting 28a, 28b provided on the frame when the support 14 pivots.

The support 14 also comprises, in the extension of the base 26, a head 30 comprising a transverse groove 32, in U, to receive the structure 16 and wherein the structure 16 can move in translation perpendicular to the axis longitudinal anchor 4 when taken away by the body 12.

The head 30 also comprises, with respect to the rod 6a, a groove 34 receiving the rod 6a and wherein said rod 6a can pivot and come into abutment when the body 12 pivots.

The operation of the exhaust shown in Figs. 1 and 2 is explained below.

In the rest phase, the anchor 4 is at rest, the rod 6a abuts on the groove 34 and the tail 27 of the support 14 bears on the limiting pin 28b.

The tooth 36 of the first escape wheel 2 is supported on the surface of the cut which forms the pallet 22 of the anchor 4. This surface is the rest plane of the pallet. Thus, the exhaust wheels are in the rest position and can not rotate. This configuration corresponds to the configuration of FIG. 2.

Then, the plate 10 rotates in the counterclockwise direction so that the plate pin 8 comes into contact with the fork 6. This is the beginning of the release. The pin 8 drives the fork 6 and thus the body 12 of the anchor 4 which pivots about the axis 15 in a clockwise direction. By pivoting, the body 12 causes the displacement in translation of the structure 16 towards the second wheel 3, so that the pallet 22 is disengaged from the tooth 36. The first escape wheel 2 is released and can rotate in the clockwise, so that the second escape wheel can also rotate but counterclockwise. This configuration corresponds to the configuration of FIG. 1.

The support 14 remains stationary until the rod 6b abuts against the groove 34. The pin 8 then drives the fork, and thus the body 12, the structure 16 and the support 14 which rotate together around the axis 15 in the clockwise direction. The structure 16 and therefore the pallet 24 are close to the second escape wheel 3.

The exhaust wheels 2 and 3 rotate so that the tooth 38 of the second escape wheel 3 comes into contact with the structure 16 and pushes on the horizontal surface of the cut forming the pallet 24. This corresponds to the impulse phase. The horizontal surface of the cut that forms the pallet 24 of the anchor 4 constitutes the pulse plane of the pallet. The support 14, the body 12 and the structure 16 continue to rotate clockwise until the shank 27 abuts the limiting pin 28a. The second escape wheel 3 is then blocked, and because of this, the first escape wheel 2 is stationary. There is therefore no fall or lost path since the first escape wheel 2 does not come into contact with the other pallet 22. It is directly in the rest phase, the anchor 4 and the wheels Exhaust 2 and 3 being at rest. The tooth 38 of the second escape wheel 3 rests on the horizontal surface of the cutout forming the pallet 24. It thus appears that the horizontal surface of the cutout forming the pallet 24 constitutes both the impulse plane and the plane rest of said pallet.

The plate 10 and the pin 8 start in the clockwise direction so that the fork 6 is now driven in the counterclockwise direction, the same movements as described above repeating in the opposite direction: clearance of the structure 16 in direction of the first escape wheel 2, pulse of a tooth of the first escape wheel 2 on the pallet 22, and rest. Then a new cycle resumes.

The above description shows that in the exhaust according to the invention, each pallet receives the pulse then blocks the associated escape wheel, and this alternately, the pallets working in turn. There is no simultaneous pulse. For each pallet, the impulse plane corresponds to the rest plane. Thus the fall and the lost path are removed. The push pulse also allows to suppress the draw. Security is therefore optimum. The sting, traditionally provided on the fork of the anchor to avoid a reversal in case of draw, can be removed.

The exhaust according to the invention is therefore simpler to achieve than existing advanced exhausts. It is easier to adjust. It can be used with the base of a conventional oscillator, identical to that used for known escapements of the Swiss anchor type. In addition, the small plate present in the traditional oscillators can be deleted since the anchor used in the invention does not include stinger. The manufacture and industrialization of the oscillator can be simplified. However, it is obvious that the sting and the small plate can be preserved if necessary.

The exhaust according to the invention also reduces the friction impulse since the pulse is not by friction of the tooth on the pallet of the anchor, but by pushing on the pallet.

The push pulse and the symmetrical geometric arrangement of the various elements of the exhaust make it possible to optimize the impulse and to have a regularity of the impulse between the exhaust wheel rotating in the clockwise direction and the exhaust wheel rotating counterclockwise.

It is obvious that the wheels can be arranged in other configurations, the geometry of the anchor and the size of the arms are then adapted to these configurations. Likewise, the shape of the anchor is not limited to the examples of the present description. Any form of anchor comprising pallets describing an alternating movement according to the invention can be envisaged.

The clearance is also linear and regular, without dynamic recoil. The energy losses are reduced.

A complementary system for having a constant force can be easily adapted to the anchor used in the invention.

[0042] Referring to FIGS. 3 and 4, there is shown a second alternative embodiment. In this variant, the first 40 and second 41 exhaust wheels are superimposed and concentric. They each comprise an internal toothing and are arranged so that the teeth are inverted and offset. The escape wheels 40 and 41 are intended to be kinematically connected to a finishing gear train (not shown) and rotate in opposite directions by means of a gear (not shown) interposed between one of the escape wheels 40, 41 and the finishing gear.

According to the invention, the anchor 42 comprises a body 44 pivotally mounted on a support 46 about an axis 48. The body 44 comprises a cylindrical portion of annular section, the center of which is crossed by the axis 48. A rod 50a, terminated by the fork 50, protrudes perpendicularly from the cylinder. In addition, the anchor 42 comprises a structure articulated on the body 44, and disposed substantially parallel to the rod 50a or the longitudinal axis of the anchor 42. The structure is arranged to move in longitudinal translation relative to the support 46. For this purpose, the structure comprises two arms 52, 54 of parallelepipedal shape. Each arm 52, 54 has at one end a finger 56 mounted in an oblong orifice 58 provided on the body 44 and in which the finger 56 can circulate. At its other end, each arm 52, 54 has a right-angled cut-out so as to form respectively a first pallet 60 and a second pallet 62. The cuts are made so that the pallets 60 and 62 are in reversed positions. Advantageously, as will be seen below, the outer lateral surface of the cutout forms both the pulse plane and the rest plane of the pallet.

In this variant, the support 46 is fixedly mounted on the frame of the timepiece so that the ends of the arms 52, 54 carrying the pallets 60, 62 are close to the internal teeth of the wheels of the watch. Exhaust 40, 41. The support 46 comprises a circular housing in which the cylindrical portion of the body 44 of the anchor 42 can be rotated about the axis 48. The support 46 also comprises two grooves 64, in a U, parallel to the longitudinal axis of the anchor 42, to receive the structure and in each of which each of the arms 52, 54 of the structure can move in translation parallel to the longitudinal axis of the anchor 42. The support 46 also comprises, in view of the rod 50a, a groove 66 receiving the rod 50a and wherein said rod 50a can pivot and abut when the body 44 pivots.

The operation of the exhaust shown in Figs. 1 and 2 is explained below and is similar to the operation of the first embodiment.

In the rest phase, the rod 50a of the anchor is in abutment against the groove 66 and a tooth of the first escape wheel 40 bears on the outer lateral surface of the cut which forms the first pallet 60. This surface constitutes the rest plane of the pallet. Thus, the exhaust wheels 40 and 41, which can not rotate, are in the rest position. The pallets being staggered, the second pallet 62 does not work with its associated escape wheel 41.

Then, the plate 68 rotates clockwise so that the plate pin 70 comes into contact with the fork 50. This is the beginning of the release. The pin 70 drives the fork 50 and thus the body 44 of the anchor 42 which pivots about the axis 48 in the counterclockwise direction. By pivoting, the body 44 causes the displacement in longitudinal translation of the arms 52, 54. More particularly, the arm 52 rises, so that the pallet 60 emerges from the tooth that blocked it. The first escape wheel 40 is released and can rotate clockwise, so that the second escape wheel 41 can also rotate but counterclockwise.

The anchor 42 continues to pivot so that the second pallet 62 descends and approaches the toothing of the second escape wheel 41.

The escape wheels 40 and 41 rotate until a tooth 72 of the second escape wheel 41 comes into contact with the second pallet 62 and pushes on the outer lateral surface of the cut forming said pallet 62. This corresponds to the impulse phase, shown in FIG. 4. The outer lateral surface of the cut which forms the pallet 62 of the anchor 42 constitutes the pulse plane of the pallet. The anchor 42 continues to pivot in the counterclockwise direction until the rod 50a abuts against the groove 66. The second escape wheel 41 is then locked, and thereby the first wheel of Exhaust 40 is also immobile. There is therefore no fall or lost path since the first escape wheel 40 does not come into contact with the other pallet 60. It is directly in the rest phase, the anchor 42 and the wheels 40 and 41 exhaust being at rest. The tooth 72 of the second escape wheel 41 rests on the outer lateral face of the cutout forming the pallet 62. It therefore appears that the outer lateral surface of the cutout forming the pallet 62 constitutes both the impulse plane and the rest plan of said pallet.

The plate 68 and the pin 70 start in the counterclockwise direction so that the fork 50 is now driven clockwise, the same movements as described above repeating in the opposite direction: release of the pallet 62 by raising the arm 54 and bringing the pallet 60 closer by lowering the arm 52 towards the first escape wheel 40, pulse of a tooth of the first escape wheel 40 on the pallet 60, and rest. Then a new cycle resumes.

The advantages of this construction are the same as for the first embodiment. In particular, each pallet receives the push pulse then blocks the associated escape wheel, and this alternately, the pallets working in turn. There is no simultaneous pulse. For each pallet, the impulse plane corresponds to the rest plane. Thus the fall, the lost path and the draw are removed.

Claims (9)

Anchor escapement for a timepiece comprising: a first (2, 40) and a second (3, 41) escape wheel intended to be kinematically connected to a finishing train, said first and second escape wheels being arranged so as not to mesh with one another; with the other, - An anchor (4, 42) provided with a first (22, 60) and a second (24, 62) pallets arranged to cooperate with respectively said first (2, 40) and second (3, 41) wheels. exhaust, and a fork (6, 50) arranged to cooperate with a balance plate (10, 68) in order to supply energy, characterized in that it further comprises a gear connecting kinematically the first (2, 40) and second (3, 41) escape wheels and arranged so that said first (2, 40) and second (3, 41) exhaust wheels rotate in opposite directions, and in that that the first (22, 60) and second (24, 62) vanes are arranged to work, with respectively said first (2, 40) and second (3, 41) escape wheels, alternately. 2. Exhaust according to claim 1, characterized in that the anchor (4, 42) comprises: a support (14, 46), a body (12, 44) pivotally mounted on said support (14, 46) about an axis (15, 48), said body (12, 44) comprising the fork (6, 50), a structure (16, 52, 54) mounted articulated on said body (12, 44), arranged to move in translation relative to said support (14, 46), and having two ends carrying respectively the first (22, 60) and second (24, 62) pallets. 3. Exhaust according to claim 2, characterized in that the first (2) and second (3) exhaust wheels are separated and in that said support (14) is arranged to be pivotally mounted on a frame of the room d watchmaking. 4. Exhaust according to claim 3, characterized in that the structure (16) comprises a single arm having in its center a finger (18) mounted articulated in the body (12) of the anchor (4) and carrying a pallet ( 22, 24) at each of its ends, said arm being arranged to move relative to the support (14) in a translation movement perpendicular to the longitudinal axis of the anchor (4). 5. Exhaust according to claim 2, characterized in that the first (40) and second (41) exhaust wheels are superimposed and concentric, and in that said support (46) is arranged to be fixedly mounted on a frame of the timepiece. 6. Exhaust according to claim 5, characterized in that the structure comprises two arms (52, 54) each terminated at one end by a finger (56) mounted articulated in the body (44) of the anchor (42) and at the other end by a pallet (60, 62), said arms (52, 54) being arranged to move relative to the support (46) in a translation movement parallel to the longitudinal axis of the anchor (42) . 7. Exhaust according to any one of claims 2 to 6, characterized in that the structure comprises, at its ends respectively carrying the first (22, 60) and second (24, 62) pallets, a cutout one of which faces form both the pulse plane and the rest plane of the pallet. 8. Exhaust according to any one of claims 1 to 7, characterized in that the fork of the anchor does not include a stinger, so that the balance plate is a single tray, having no small tray. 9. Timepiece comprising an exhaust according to any one of claims 1 to 8.