FR3048790A1 - MECHANISM FOR A WATCHING PART, A WATCHMAKING MOVEMENT AND A WATCHPIECE COMPRISING SUCH A MECHANISM. - Google Patents

Abstract

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

Description

Mechanism for a timepiece, watch movement and timepiece including such a mechanism.

FIELD OF THE INVENTION

The present invention relates to mechanisms for timepieces, as well as to watch movements and timepieces comprising such mechanisms. BACKGROUND OF THE INVENTION Mechanisms for a timepiece are known comprising: a regulator comprising at least a first regulating member mounted resiliently on a support for oscillating, an anchor adapted to cooperate with a power distribution member provided with teeth and intended to be solicited by an energy storage device, said anchor being controlled by the first regulating member to regularly and alternately block and release the energy distribution member, so that said power distribution member is moves step by step under the load of the energy storage device according to a repetitive motion cycle, and said anchor being adapted to transfer mechanical energy to the regulator during this repetitive motion cycle.

Known mechanisms of this type have the particular disadvantage that their oscillating masses are sensitive to shocks, to gravity and more generally to acceleration and dynamic phenomena, which can disturb the oscillatory movements of the mechanism and therefore the counting of the time achieved by this mechanism . OBJECTS AND SUMMARY OF THE INVENTION The present invention is intended to overcome this disadvantage. For this purpose, according to the invention, a mechanism of the kind in question is characterized in that the regulator further comprises a second regulating member resiliently mounted on said support for oscillating, the first and second regulating members being interconnected to have always symmetrical and opposite movements, and in that it further comprises a balancing member which is controlled by the second regulating member to move in symmetrical and opposed movements to the anchor.

Thanks to these provisions, a dynamic balance of the oscillating masses of the mechanism, which allows to significantly reduce its sensitivity to shock, gravity and generally acceleration. It is thus possible to obtain a better temporal accuracy of the mechanism since it is independent of the dynamic phenomena.

In various embodiments of the mechanism according to the invention, one or more of the following provisions may also be used: the anchor has a certain mass and the balancing member has a substantially identical mass, for example between 90% and 110% of the weight 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 in reciprocating motion in circular translation, with a first amplitude of oscillation in the first direction of translation and with a non-zero amplitude of secondary oscillation, 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 arms 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 resiliently 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 oscillation amplitude in the second translation direction and a non-zero secondary oscillation amplitude, perpendicular to the second direction of translation, the second amplitude of oscillation being greater than the amplitude of secondary oscillation of the anchor and the balancing member; the second oscillation amplitude is at least 10 times greater than the secondary oscillation amplitude of the anchor and the balancing member; the anchor and the balancing member are mounted on the support respectively by two elastic suspension arms substantially perpendicular to the second direction of translation; the anchor and the balancing member are respectively connected to the first and second regulating members by first and second driving elastic branches; the mechanism is monolithic and realized in a single plate.

Furthermore, the invention also relates to a watch movement comprising the mechanism as defined above and said power distribution member.

Finally, the invention also relates to a timepiece comprising a movement as defined above. BRIEF DESCRIPTION OF THE DRAWINGS Other features and advantages of the invention will become apparent from the following description of one of its embodiments, given by way of non-limiting example, with reference to the accompanying drawings.

In the drawings: FIG. 1 is a schematic view of a timepiece that can comprise a mechanism according to one embodiment of the invention, FIG. 2 is a block diagram of the movement of the timepiece of FIG. 1, FIG. 3 is a plan view of a portion of the movement of FIG. 2, including the regulator, the anchor, and the power distribution member, and FIGS. 4 and 5 are views similar to FIG. Figure 3, showing different positions of the mechanism. DESCRIPTION DETAILED DESCRIPTION In the different figures, the same references designate identical or similar elements.

FIG. 1 represents a timepiece 1 such as a watch, comprising: a housing 2, a watch movement 3 contained in the housing 2, generally a winding 4, a dial 5, a glass 6 covering the dial 5, a time indicator 7, comprising for example two needles 7a, 7b respectively for hours and minutes, arranged between the glass 6 and the dial 5 and actuated by the watch movement 3.

As shown diagrammatically in FIG. 2, the watch movement 3 can comprise, for example: a device 8 for storing mechanical energy, generally a mainspring, a mechanical transmission 9 driven by the mechanical energy storage device 8, aforementioned time indicator 7, a power 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 power distribution member is moved stepwise at constant time intervals. The anchor 11 and the regulator 12 form a mechanism 13 which may advantageously be monolithic, as will be explained hereinafter.

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 flat) and whose moving parts 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 may 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), between about 10 mm and 40 mm. X and Y are two perpendicular axes defining the plane of the plate 14.

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

The various members formed in the plate 14, are obtained by making openings in the plate 14, obtained by any manufacturing process used in micromechanics, in particular the processes used for the manufacture of MEMS.

In the case of a silicon plate 14, the plate can be locally removed for example by deep reactive ion etching (DRIE) or possibly by laser cutting.

In the case of an iron / nickel plate 14, the plate could be made in particular by the LIGA method, or by laser cutting.

In the case of a steel or titanium plate 14, the plate 14 may be hollowed out for example by wire electroerosion (WEDM).

The constituent parts of the mechanism will now be described in more detail. Some of these parts are rigid and others (especially those called "elastic branches") are elastically deformable, mainly in flexion. 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 higher in the XY plane than the elastic parts. Typical dimensions for elastic links, for example the elastic branches which will be described below, include lengths for example between 5 and 13 mm and widths for example between 0.01 mm (10 pm) 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 aspect ratio possible is preferred to limit the modes oscillation off plane.

The plate 14 forms a fixed external 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 may at least partially surround the energy distribution member 10, the anchor 11 and the regulator 12. The energy dispensing member 10 may be a mounted escape wheel rotating for example on the support plate 14a, so as to be rotatable about an axis of rotation Z perpendicular to the XY plane of the plate 14. The energy distribution member 10 is biased 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 piece which may comprise a rigid body 18 extending for example parallel to the axis X and two rigid parallel side arms 19, 20 extend for example parallel to the Y axis on either side of the power distribution member 10. The arms 19, 20 respectively comprise two stop members 21, 22 in the form of fingers projecting from each other. towards the other in the direction of the X axis 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 their sides. other 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. The anchor 11 may further comprise a resilient monostable member 11a, which may be present in the form of an elastic tongue whose free end comes to bear on the teeth 17 of the energy dispensing 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 axis Y from the free end of the rigid arm 19, extending the rigid arm 19 to a rigid support 11c which carries the elastic member monostable lia. The monostable elastic member 11a may extend along the Y axis towards the regulator 12, from the rigid support 11c. The monostable elastic member 11a serves for the energy distribution member 10 to transfer a precisely determined mechanical energy to the regulator at each cycle of operation 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 axis X, in the direction of translation 02. The balancing member 25 may for example comprise: a rigid body 26 extending parallel to the axis X, symmetrically to the body 18 of the anchor relative to an axis of symmetry YO parallel to the aforementioned Y axis, and a rigid arm 28 extending along the Y axis to the regulator 12, symmetrically to the arm 24 of the anchor relative to the axis of symmetry YO. The balancing member 25 may also be inside the frame 15 and may 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 elastic branches 23 of the anchor 11. Optionally, the elastic branches 23 may 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 oscillation amplitude in the translation direction O 2 and a non-zero secondary oscillation amplitude perpendicular to the translation direction O 2. Said oscillation amplitude in the translation direction O 2 is greater than the amplitude secondary oscillation of the anchor and the balancing member, for example at least 10 times greater than the secondary oscillation amplitude of the anchor and the balancing member. The balancing member 25 may 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 balancing member 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 quite symmetrical (for example the anchor is in contact with the power distribution member while the balancing member 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 and an elastic suspension which is adapted so that the first and second regulating members 29, 30 oscillate according to the Y axis, in a translation direction 01.

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 X axis and connected to the frame 15.

Each of the first and second regulating members 29, 30 is thus mounted on the frame 15 to oscillate in circular translation, with an amplitude of oscillation in the translation direction 01 and with a non-zero secondary oscillation amplitude, perpendicular to the translation direction 01. Said oscillation amplitude in the translation direction 01 is greater than the secondary oscillation amplitude of the first and second regulating members, for example at least 10 times greater than the secondary oscillation amplitude .

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

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

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

The elastic branches 36 may, for example, extend substantially along the X axis. The driving elastic branches 36 may 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 body. 'balancing.

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

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

The lateral arms 39 may be respectively connected 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 ΥΟ, since the frame 15 to a head 42 which may for example extend along the axis X 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 center of rotation P, extending along the X axis between two enlarged heads 46, two rigid intermediate bodies 47, 48 disposed on either side of the central core 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 symmetrical elastic branches 51 of the elastic branches 50, respectively connecting the rigid intermediate body 48 to the other free ends of the enlarged heads 46, two elastic branches 52 connecting the rigid intermediate body 48 respectively to the ends of the part hundred 38 of the balancing lever.

The balancing lever 37 imposes on the first and second regulating members 29, 30 to move symmetrically and opposite in the direction of translation 01, which, by means of the driving elastic branches 36, imposes on the anchor 11 and the balancing member 25 to move symmetrically and opposite in the direction of translation 02, as shown in Figures 4 and 5 which show the two end positions of the mechanism 13.

These opposing movements allow a dynamic balancing mechanism 13, which reduces the sensitivity of the mechanism 13 shock, gravity and more generally 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, we use the notions of up / down, right / left to clarify the description with respect to the orientation of the drawings of Figures 3 to 5, but these indications are not limiting.

In the situation of FIG. 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 storage device. 8 energy, and during this movement the elastic member monostable lia has bent and then relaxed 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 to the left in FIG. 3 is then in abutment against the stop member 21 situated 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 01 between the two extreme positions respectively represented in FIGS. 4 and 5, with a frequency f which can be for example between 20 and 30 Hz.

On a half cycle of movement, for example when the first regulating member 29 moves from the "high" end position of FIG. 4 to the "low" end position of FIG. 5, the second regulating member 30 moves from the extreme position 4, at the extreme "high" position of FIG. 5, because of the presence of the balancing lever 37. During this time, the anchor 11 moves from the extreme "left" position of the FIG. 4 at the extreme "right" position of FIG. 3 at the moment when the first and second regulating members pass into the neutral position of FIG. 3, then the anchor 11 returns to the left 5 to the "left" extreme position. of Figure 5, where the energy dispensing member 10 escapes again and turns a step under the stress of the energy storage device 8. During this time, the balancing member 25 follows a movement symmetrical and opposite to the anchor 11. The anchor 11 and the e balancing 25 oscillate with a frequency 2f in the direction of translation 02.

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

Claims (16)

1. Mechanism for a timepiece comprising: a regulator (12) comprising at least a first regulating member (29) resiliently mounted on a support (15) for oscillating, an anchor (11) adapted to cooperate with a dispensing member; energy (10) provided with teeth (17) and intended to be biased 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 power distribution member (10), so that said power distribution member (10) moves stepwise under the load of the energy storage device (8) in a repetitive motion cycle, and said anchor (11) being adapted to transfer mechanical energy to the regulator (12) during this repetitive motion cycle, characterized in that the regulator (12) further comprises a second regulating member (30) resiliently mounted on said s upport (15) for oscillating, 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 in symmetrical movements and opposed to the anchor (11). 2. Mechanism according to claim 1, wherein the anchor (11) has a certain mass and the balancing member (25) has a substantially identical mass, for example between 90% and 110% of the mass of the mass. 'anchor. 3. Mechanism according to any one of the preceding claims, wherein the first and second regulating members (29, 30) are mounted on the support (15) to oscillate in translation in a first direction of translation (01). 4. Mechanism according to claim 3, wherein each of the first and second regulating members (29, 30) is mounted on the support (15) to oscillate in reciprocating motion in circular translation, with a first amplitude of oscillation in the first translation direction (01) and with a non-zero secondary oscillation amplitude, perpendicular to the first translation direction (01), the first oscillation amplitude being greater than the secondary oscillation amplitude of the first and second regulating members (29, 30). 5. Mechanism according to claim 4, wherein the first oscillation amplitude is at least 10 times greater than the secondary oscillation amplitude of the first and second regulating members (29, 30). 6. Mechanism according to claim 4 or claim 5, wherein each of the first and second regulating members (29, 30) is mounted on the support (15) by two elastic suspension arms (31) substantially perpendicular to the first direction of translation (01). 7. Mechanism according to any one of the preceding claims, wherein the first and second regulating members (29, 30) are interconnected by a pivoting balancing lever (37). 8. Mechanism according to any one of the preceding claims, wherein the anchor (11) and the balancing member (25) are resiliently mounted on the support (15) to oscillate in translation in a second direction of translation ( 02). 9. Mechanism according to claim 8, wherein the second direction of translation (02) is substantially perpendicular to the first direction of translation (01). 10. Mechanism according to claim 8 or claim 9, wherein the anchor (11) and the balancing member (25) are each mounted on the support (15) to oscillate in circular translation, with a second amplitude of oscillation in the second translation direction (02) and a non-zero secondary oscillation amplitude perpendicular to the second translation direction (02), the second oscillation amplitude being greater than the secondary oscillation amplitude the anchor (11) and the balancing member (25). 11. Mechanism according to claim 10, wherein the second amplitude of oscillation is at least 10 times greater than the secondary oscillation amplitude of the anchor (11) and the balancing member (25). 12. Mechanism according to any one of claims 8 to 11, wherein the anchor (11) and the balancing member (25) are mounted on the support (15) respectively by two elastic suspension arms 23, 27 ) substantially perpendicular to the second translation direction (02). 13. Mechanism according to any one of the preceding claims, wherein the anchor (11) and the balancing member (25) are respectively connected to the first and second regulating members (29, 30) by first and second branches. driving elastics (36). 14. Mechanism according to any one of the preceding claims, monolithic and made in a single plate (14). 15. Watch movement (3) comprising a mechanism (13) according to any one of the preceding claims and said power distribution member (11). 16. Timepiece (1) comprising a watch movement (3) according to claim 15.