CH713790B1 - Mechanism for a timepiece, timepiece movement and timepiece comprising such a mechanism. - Google Patents

Abstract

Mechanism for a timepiece comprising two regulating members (29, 30) elastically mounted and interconnected to oscillate in opposition, and an anchor (11) adapted to cooperate with an energy distribution member (10) acted upon by a device energy storage. The anchor is controlled by the first regulating member (29) to regularly and alternately block and release the energy distribution member. The mechanism further comprises a balancing member (25) which is controlled by the second regulating member (30) to move according to movements symmetrical and opposite to the anchor.

Description

FIELD OF THE INVENTION

The present invention relates to mechanisms for timepieces, as well as watch movements and timepieces comprising such mechanisms.

BACKGROUND OF THE INVENTION

[0002] Mechanisms are known for timepieces comprising: a regulator comprising at least a first regulating member mounted elastically on a support to oscillate, an anchor adapted to cooperate with an energy distribution member provided with teeth and intended to be acted upon by an energy storage device, said anchor being controlled by the first regulating member to regularly and alternately block and release the energy distribution, whereby said energy distribution member moves step by step under the stress of the energy storage device according to a cycle of repetitive movement, and said anchor being adapted to transfer mechanical energy to the regulator during this repetitive motion cycle.

[0003] Known mechanisms of this type have the particular drawback that their oscillating masses are sensitive to shocks, to gravity and more generally to accelerations and dynamic phenomena, which can disturb the oscillatory movements of the mechanism and therefore the counting of the time carried out by this mechanism.

OBJECTS AND SUMMARY OF THE INVENTION

The present invention particularly aims to overcome this drawback.

To this end, according to the invention, a mechanism of the kind in question is characterized in that the regulator further comprises a second regulating member elastically mounted on said support to oscillate, the first and second regulating members being interconnected to always have symmetrical and opposite movements, and in that it further comprises a balancing member which is controlled by the second regulating member to move according to symmetrical and opposite movements to the anchor.

[0006] Thanks to these provisions, a dynamic balancing of the oscillating masses of the mechanism is achieved, which makes it possible to significantly reduce its sensitivity to shocks, to gravity and generally to accelerations. It is thus possible to obtain a better temporal precision of the mechanism since it is independent of the dynamic phenomena.

In various embodiments of the mechanism according to the invention, it is also possible to use one and/or the other of the following provisions: the anchor has a certain mass and the balancing member has a substantially identical mass, for example between 90% and 110% of the mass of the anchor; the first and second regulating members are mounted on the support to oscillate in translation in a first direction of translation; each of the first and second regulating members is mounted on the support to oscillate according to an alternating movement in circular translation, with a first amplitude of oscillation in the first direction of translation and with a secondary amplitude of oscillation, non-zero, perpendicular to the first translation direction, the first oscillation amplitude being greater than the secondary oscillation amplitude of the first and second regulating members; the first oscillation amplitude is at least 10 times greater than the secondary oscillation amplitude of the first and second regulating members; each of the first and second regulating members is mounted on the support by two elastic suspension branches substantially perpendicular to the first direction of translation; the first and second regulating members are interconnected by a pivoting balancing lever; the anchor and the balancing member are elastically mounted on the support to oscillate in translation in a second direction of translation; the second direction of translation is substantially perpendicular to the first direction of translation; the anchor and the balancing member are each mounted on the support to oscillate in circular translation, with a second amplitude of oscillation in the second direction of translation and a secondary amplitude of oscillation, non-zero, perpendicular to the second direction of translation, the second oscillation amplitude being greater than the secondary oscillation amplitude of the anchor and of the balancing member; the second oscillation amplitude is at least 10 times greater than the secondary oscillation amplitude of the anchor and of the balancing member; the anchor and the balancing member are mounted on the support respectively by two elastic suspension branches substantially perpendicular to the second direction of translation; the lever and the balancing member are respectively connected to the first and second regulating members by first and second elastic drive branches; the mechanism is monolithic and made in a single plate.

[0008] Furthermore, the invention also relates to a timepiece movement comprising the mechanism as defined above and said energy distribution member.

[0009] Finally, the invention also relates to a timepiece comprising a movement as defined above.

BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics and advantages of the invention will appear during the following description of one of its embodiments, given by way of non-limiting example, with reference to the accompanying drawings.

[0011] In the drawings: FIG. 1 is a schematic view of a timepiece which may include a mechanism according to one embodiment of the invention, Figure 2 is a block diagram of the movement of the timepiece of Figure 1, figure 3 is a plan view of part of the movement of figure 2, comprising the regulator, the anchor, and the energy distribution member, and Figures 4 and 5 are views similar to Figure 3, showing different positions of the mechanism.

MORE DETAILED DESCRIPTION

In the various figures, the same references denote identical or similar elements.

[0013] Figure 1 shows a timepiece 1 such as a watch, comprising: a box 2, a watch movement 3 contained in the case 2, generally, a crown 4, a dial 5, a crystal 6 covering the dial 5, a time indicator 7, comprising for example two hands 7a, 7b respectively for the hours and the minutes, arranged between the crystal 6 and the dial 5 and actuated by the watch movement 3.

As shown schematically in Figure 2, the watch movement 3 may include for example: a device 8 for storing mechanical energy, generally a mainspring, a mechanical transmission 9 moved by the device 8 for storing mechanical energy, the aforementioned time indicator 7, an energy distribution member 10 (for example an escape wheel), an anchor 11 adapted to sequentially retain and release the energy distribution member 10, a regulator 12, which is a mechanism comprising an oscillating regulating member controlling the anchor 11 to move it regularly so that the energy distribution member is moved step by step at constant time intervals.

The anchor 11 and the regulator 12 form a mechanism 13 which can advantageously be monolithic, as will be explained below.

[0016] The watch movement 3 will now be explained in more detail with the aid of FIG. 3, which represents a particular case where the mechanism 13 is a monolithic system formed in the same plate 14 (usually planar) and whose parts mobile are designed to move essentially in a mean plane of said plate 14. The invention is however not limited to such a monolithic system.

The plate 14 can be thin, for example about 0.05 to about 1 mm, depending on the nature of the material of the plate 14.

The plate 14 may have transverse dimensions, in the XY plane of the plate (in particular width and length, or diameter), of between about 10 mm and 40 mm. X and Y are two perpendicular axes defining the plane of plate 14.

The plate 14 can be made of any suitable rigid material, preferably having a low Young's modulus to have good properties of elasticity and a low oscillation frequency. Examples of materials that can be used to make plate 14 include silicon, nickel, iron/nickel alloy, steel, titanium. In the case of silicon, the thickness of plate 14 can for example be between 0.2 and 0.6 mm.

The various bodies formed in the plate 14 are obtained by making openings in the plate 14, obtained by any manufacturing method used in micromechanics, in particular the methods used for the manufacture of MEMS.

[0021] In the case of a plate 14 of silicon, the plate can be locally hollowed out, for example by deep reactive ion etching (DRIE - “Deep Reactive Ion Etching”) or optionally by laser cutting.

In the case of a plate 14 of iron / nickel, the plate could be produced in particular by the LIGA process, or by laser cutting.

In the case of a plate 14 of steel or titanium, the plate 14 can be hollowed out, for example by wire electrical discharge erosion (WEDM).

The component parts of the mechanism will now be described in more detail. Some of these parts are rigid and others (in particular those called "elastic branches") are elastically deformable, essentially in bending. The difference between the rigid parts and the elastic parts is their stiffness in the XY plane of the plate 14, which is due to their shape and in particular to their slenderness. The slenderness can be measured in particular by the slenderness ratio (length/width ratio of the part concerned). For example, the rigid parts have a stiffness at least about 100 times greater in the XY plane than the elastic parts. Typical dimensions for the elastic links, for example the elastic branches which will be described below, include lengths comprised for example between 5 and 13 mm and widths comprised for example between 0.01 mm (10 μm) and 0.04 mm (40 µm), especially about 0.025 mm (25 µm). Given the widths of the beams and the thickness of the plate 14, the aspect ratio of these beams in longitudinal section is between 5 and 60. The largest possible aspect ratio is to be preferred to limit the modes of out-of-plane oscillation.

The plate 14 forms a fixed outer frame 15 which is fixed to a support plate 14a, for example by screws or the like (not shown) passing through holes 15a of the frame 15. The support plate 14a is secured to the housing 2 of the timepiece 1. The frame 15 can at least partially surround the energy distribution member 10, the lever 11 and the regulator 12.

[0026] The energy distribution member 10 may be an escapement wheel rotatably mounted for example on the support plate 14a, so as to be able to rotate around an axis of rotation Z0 perpendicular to the plane XY of the plate. 14. The energy distribution member 10 is stressed by the energy storage 8 in a single direction of rotation 16.

The energy distribution member 10 has external teeth 17.

The anchor 11 is a rigid part which may comprise a rigid body 18 extending for example parallel to the X axis and two parallel rigid side arms 19, 20 extending for example parallel to the Y axis of either side of the energy distribution member 10. The arms 19, 20 respectively comprise two stop members 21, 22 in the form of fingers projecting towards each other in the direction of the axis X from the arms 19, 20.

The anchor 11 is elastically connected to the frame 15, so as to be able to move parallel to the axis X, in a direction of translation 02. Advantageously, the anchor 11 can be connected to the frame 15 by an elastic suspension , comprising for example two elastic branches 23 substantially parallel to the axis Y. Optionally, the elastic branches 23 can be connected to the body 18 and arranged on either side of the side arms 19, 20, framing these side arms.

The anchor 11 may further comprise a rigid arm 24 extending along the Y axis towards the regulator 12, opposite the arm 20.

[0031] The anchor 11 may further comprise a monostable elastic member 11a, which may be in the form of an elastic tongue whose free end comes to bear on the teeth 17 of the energy distribution member 10 The monostable elastic member 11a can be connected to the rigid arm 19 of the anchor 11, for example by an elastic suspension comprising two parallel elastic branches 11b extending along the Y axis from the free end of the rigid arm 19, by extending the rigid arm 19 as far as a rigid support 11c which carries the monostable elastic member 11a. The monostable elastic member 11a can extend along the Y axis in the direction of the regulator 12, from the rigid support 11c. The monostable elastic member 11a serves to ensure that the energy distribution member 10 transfers a precisely determined mechanical energy to the regulator, at each operating cycle of the watch movement 3, as explained in European patent application No. 14197015.

The mechanism further comprises a balancing member 25, which is mounted on the frame 15 to oscillate parallel to the X axis, in the direction of translation O2. The balancing member 25 may for example comprise: a rigid body 26 extending parallel to the X axis, symmetrically to the body 18 of the anchor with respect to an axis of symmetry Y0 parallel to the aforementioned Y axis, and a rigid arm 28 extending along the axis Y towards the regulator 12, symmetrically to the arm 24 of the anchor with respect to the axis of symmetry Y0.

[0033] The balancing member 25 can also be inside the frame 15 and can be connected to the frame 15 by an elastic suspension, comprising for example two elastic branches 27 substantially parallel to the axis Y and symmetrical with the branches elastics 23 of the anchor 11. Optionally, the elastic branches 23 can be connected to the body 26 of the balancing member 25.

The anchor 11 and the balancing member 25 are each mounted on the frame 15 to oscillate in circular translation, with an amplitude of oscillation in the direction of translation 02 and a secondary oscillation amplitude, non- null, perpendicular to the direction of translation 02. Said amplitude of oscillation in the direction of translation 02 is greater than the amplitude of secondary oscillation of the anchor and of the balancing member, for example at least 10 times greater than the secondary oscillation amplitude of the anchor and the balancing device.

The balancing member 25 can advantageously have a mass substantially identical to that of the anchor 11, for example between 90% and 110% of the mass of the anchor 11. The mass of the member balancing is very close to that of the anchor but is not necessarily identical to take into account the fact that the stresses applied to one or the other of these organs are not completely symmetrical (for example the anchor is in contact with the energy distribution device while the balancing device is not).

The regulator 12 is a mechanical oscillator comprising first and second regulating members 29, 30 each forming a rigid inertial mass, each connected to the frame 15 by an elastic suspension which is adapted so that the first and second regulating members 29, 30 oscillate along the Y axis, in a direction of translation O1.

The elastic suspensions of the first and second regulating members 29, 30 may each comprise, for example, two elastic branches 31 extending substantially along the axis X and connected to the frame 15.

Each of the first and second regulating members 29, 30 is therefore mounted on the frame 15 to oscillate in circular translation, with an amplitude of oscillation in the direction of translation O1 and with a secondary oscillation amplitude, non-zero. , perpendicular to the direction of translation O1. Said oscillation amplitude in the direction of translation O1 is greater than the secondary oscillation amplitude of the first and second regulating members, for example at least 10 times greater than the amplitude d secondary oscillation.

In the example shown, the first and second regulating members 29, 30 can each have a C-shape, with a main body 32 extending along the Y axis between two lateral arms 33 extending towards the inside the frame 15. The aforementioned elastic branches 31 can advantageously be connected to the free ends of the lateral arms 33, which makes it possible to have long and therefore particularly flexible elastic branches 31.

The first and second regulating members 29, 30 may be two parts symmetrical with respect to the aforementioned axis of symmetry Y0, of identical or substantially identical mass. They can define between them a free central space 34.

The first and second regulating members 29, 30 can be connected respectively to the anchor 11 and to the balancing member 25, for example by elastic drive branches 36. Thus, the first regulating member 29 controls the movements of the anchor 11 and the second regulating member 30 controls the movements of the balancing member 25.

The elastic branches 36 can for example extend substantially along the axis X. The elastic drive branches 36 can in particular be connected respectively to the free ends of the rigid arm 24 of the anchor and of the rigid arm 28 of the balancing organ.

Optionally, each of the first and second regulating members 29, 30 may comprise a notch 35 open along the X axis between the main body 32 and the rigid arm 33 closest to the anchor 11 or the regulating member. balancing 25, and the corresponding elastic drive branch 36 can be connected to the main body 32 at the bottom of said notch 35, which makes it possible to lengthen the elastic drive branches 36 and therefore to increase their flexibility.

In the free interior space 34 is arranged a rigid balancing lever 37, pivotally mounted around a central center of rotation P. The balancing lever 37 may optionally have a substantially M-shaped shape, with a V-shaped central part 38 diverging from the center of rotation P and two side arms 39.

The side arms 39 can be connected respectively to the first and second regulating members 29, 30, for example by two elastic branches 40 extending substantially along the Y axis.

The balancing lever 37 can be mounted, by an elastic suspension 43, on a rigid support 40a rigidly connected to the frame 15. The rigid support 40a can for example comprise an arm 41 extending on the axis of symmetry Y0, from the frame 15 to a head 42 which can for example extend along the X axis by giving the support 40a a T-shape.

The elastic suspension 43 may for example comprise: a rigid pivoting member 44 disposed inside the balancing lever 37, comprising for example a central core 45 at the level of the center of rotation P, extending along the axis X between two widened heads 46, two rigid intermediate bodies 47, 48 arranged on either side of the central web 45 near the center of rotation P, two elastic branches 49 respectively connecting the free ends of the head 42 of the rigid support 41 to the rigid intermediate body 47, two elastic branches 50 respectively connecting the rigid intermediate body 47 to one of the free ends of the enlarged heads 46, two elastic branches 51 symmetrical with the elastic branches 50, respectively connecting the rigid intermediate body 48 to the other of the free ends of the widened heads 46, two elastic branches 52 connecting the rigid intermediate body 48 respectively to the ends of the central part 38 of the balancing lever.

The balancing lever 37 requires the first and second regulating members 29, 30 to move symmetrically and oppositely in the direction of translation 01, which, via the elastic drive branches 36, imposes the anchor 11 and the balancing member 25 to move symmetrically and oppositely in the direction of translation 02, as shown in Figures 4 and 5 which show the two limit positions of the mechanism 13.

These opposing movements allow a dynamic balancing of the mechanism 13, which makes it possible to reduce the sensitivity of the mechanism 13 to shocks, to gravity and more generally to accelerations.

The previously described mechanism operates according to the principle explained in the aforementioned European patent application No. 14197015. In the following explanation of this operation, the notions of top/bottom, right/left are used to clarify the description with regard to the orientation of the drawings of FIGS. 3 to 5, but these indications are not limiting.

In the situation of Figure 3, the anchor 11 is in an extreme "right" position imposed by the elastic transmission branch 36 and the energy distribution member 10 has just pivoted under the effect of the device energy storage 8, and during this movement the monostable elastic member 11a has bent and then released by transmitting its mechanical energy in the regulator 12, as explained in the aforementioned European patent application No. 14197015. The tooth 17 of the energy distribution member located towards the left in FIG. 3 is then in abutment against the stop member 21 located on the left of the anchor 11. The elastic branches 31 are in the position of rest.

The first and second regulating members 29, 30 oscillate in the direction of translation O1 between the two extreme positions shown respectively in Figures 4 and 5, with a frequency f which may be between 20 and 30 Hz, for example.

On a half-cycle of movement, for example when the first regulating member 29 passes from the extreme “high” position of FIG. 4 to the extreme “low” position of FIG. 5, the second regulating member 30 passes from the extreme "low" position of figure 4 to the extreme "high" position of figure 5, due to the presence of the balancing lever 37. During this time, the anchor 11 passes from the extreme "left" position of figure 4 to the extreme "right" position of figure 3 at the moment when the first and second regulating organs pass into the neutral position of figure 3, then the anchor 11 returns to the left 5 to the extreme position "left" of Figure 5, where the energy distribution member 10 escapes again and rotates one step under the stress of the energy storage device 8. Meanwhile, the balancing member 25 follows a movement symmetrical and opposite to the anchor 11.

The anchor 11 and the balancing member 25 therefore oscillate with a frequency 2f in the direction of translation 02.

The operation is the same when moving then from the position of Figure 5 to that of Figure 4. The above steps are then repeated indefinitely.

Claims (14)

1. Mechanism (13) for a timepiece comprising: – a support (15), – a regulator (12) comprising a first regulating member (29) elastically mounted on the support (15) to oscillate, – an anchor (11) adapted to cooperate with an energy distribution member (10) provided with teeth (17) that includes a watch movement (3) and intended to be acted upon by an energy storage device (8) , said anchor (11) being controlled by the first regulating member (29) to regularly and alternately block and release the energy distribution member (10), so that the said energy distribution member (10) moves stepping under the stress of the energy storage device (8) according to a cycle of repetitive movement, and said anchor (11) being adapted to transfer mechanical energy to the regulator (12) during this cycle of movement repetitive, characterized in that the regulator (12) further comprises a second regulating member (30) elastically mounted on the said support (15) to oscillate, the first and second regulating members (29, 30) being interconnected to always have symmetrical and opposite movements, and in that it further comprises a balancing member (25) which is controlled by the second regulating member (30) to move according to movements symmetrical and opposite to the anchor (11). 2. Mechanism according to claim 1, in which the anchor (11) has a certain mass and the balancing member (25) has a mass of between 90% and 110% of the mass of the anchor. 3. Mechanism according to one of the preceding claims, wherein each of the first and second regulating members (29, 30) is mounted on the support (15) to oscillate according to an alternating movement in circular translation, with a first amplitude of oscillation in a first translation direction (O1) and with a non-zero secondary oscillation amplitude perpendicular to the first translation direction (O1), the first oscillation amplitude being greater than the secondary oscillation amplitude of the first and second regulating organs (29, 30). 4. Mechanism according to claim 3, in which the first oscillation amplitude is at least 10 times greater than the secondary oscillation amplitude of the first and second regulating members (29, 30). 5. Mechanism according to claim 3 or 4, wherein each of the first and second regulating members (29, 30) is mounted on the support (15) by two elastic suspension branches (31) substantially perpendicular to the first direction of translation ( O1) . 6. Mechanism according to one of the preceding claims, wherein the first and second regulating members (29, 30) are interconnected by a pivoting balancing lever (37). 7. Mechanism according to one of claims 3 to 5, wherein the anchor (11) and the balancing member (25) are elastically mounted on the support (15) to oscillate in circular translation, with a second amplitude of oscillation in a second direction of translation (02) and a secondary oscillation amplitude, non-zero, perpendicular to the second direction of translation (02), the second amplitude of oscillation being greater than the amplitude of oscillation secondary of the anchor (11) and of the balancing member (25). 8. Mechanism according to claim 7, wherein the second direction of translation (02) is substantially perpendicular to the first direction of translation (O1). 9. Mechanism according to claim 7 or 8, in which the second oscillation amplitude is at least 10 times greater than the secondary oscillation amplitude of the anchor (11) and of the balancing member (25 ). 10. Mechanism according to one of claims 7 to 9, wherein the anchor (11) and the balancing member (25) are mounted on the support (15) respectively by two elastic suspension branches (23, 27 ) substantially perpendicular to the second direction of translation (02). 11. Mechanism according to one of the preceding claims, in which the anchor (11) and the balancing member (25) are respectively connected to the first and second regulating members (29, 30) by first and second elastic branches drive (36). 12. Mechanism according to one of the preceding claims, monolithic and produced in a single plate (14). 13. Watch movement (3) comprising a mechanism (13) according to one of claims 1 to 12 and said energy distribution member (10). 14. Timepiece (1) comprising a timepiece movement (3) according to claim 13.