Timepiece comprising a damping fastening device for a timepiece movement

Abstract

The invention relates to a timepiece (1) comprising a case (4) in which a timepiece movement (2) is housed, said timepiece movement (2) being held in said case (4) by a damping fastening device (10), the damping fastening device (10) comprising at least two blades (3), each blade (3) having two opposite ends (3c, 3d) fixed, directly or indirectly, to the case (4) and to the timepiece movement (2) by fastening elements (7) cooperating with first anchor points of the timepiece movement (2) and second anchor points of the case (4) characterized in that the first anchor points of the timepiece movement are inscribed on a first circle (C1) and in that the second anchor points are inscribed on a second circle (C2), the first circle (C1) and the second circle (C2) being concentric,and in that the first anchor points (8a) and the second anchor points (8b) are not radially aligned.

Description

Technical field of the invention

[0001] The present invention relates to a timepiece comprising a shock-absorbing fastening device for a timepiece movement capable of reducing the impacts of shocks on the timepiece movement. Technological background

[0002] Two or three mounting flanges are generally used for assembling or fixing a watch movement within a case, particularly within a case body.

[0003] For example, document CH 315649 describes a fastening device for securing a watch movement within a case. The fastening device secures the watch movement by means of several flexible mounting flanges. These mounting flanges have a support section connected to the watch movement and a fastening section inserted into a cutout formed on the inner circumference of the case.

[0004] This cutout can be shaped in such a way that the casing flange can induce an adequate pre-stressing force on the watch movement in order to press and hold the watch movement in position in the case.

[0005] These fastening devices are rarely designed to withstand the effects of impacts on the case. Such impacts can lead to a loss of support at the case body or to deformation of the flanges, amplifying the acceleration experienced by the watch movement and potentially causing damage to the movement.

[0006] To address the problem of flange loss of support in the event of an impact, document CH 720282 proposed suspending a watch movement within a case using a support structure comprising a plurality of suspension triangles with ends fixed to the movement's mainplate and the case. However, such a solution is statically indeterminate in dynamic mode, resulting in minimal damping of the watch movement and increased stress at the anchor points.

[0007] Therefore, there is a need to improve the damping fastening devices of watch movements. Summary of the invention

[0008] To this end the invention proposes a timepiece comprising a damping fixing device for a timepiece movement allowing to remedy at least one of the aforementioned disadvantages.

[0009] The invention proposes a flexible and shock-absorbing fastening solution that dampens the forces transmitted to the movement during an impact, while controlling and limiting the axial movement of the watch within the case. Compared to prior art solutions, the invention offers a solution that addresses the constraints related to the maximum permissible axial movement of a watch within a case, thereby preventing the amplification of accelerations within the watch movement.

[0010] In particular, the invention proposes a timepiece comprising a damping fixing device for a timepiece movement arranged to hold said timepiece movement in a case of a timepiece while ensuring a damping effect so as to reduce the accelerations suffered by the timepiece movement during a case or glass shock.

[0011] Furthermore, the invention proposes a timepiece comprising a shock-absorbing fastening device whose reliability and robustness are improved compared to state-of-the-art solutions, so as to guarantee its proper functioning in the event of repeated shocks.

[0012] To this end, the invention relates to a timepiece comprising a case in which a timepiece movement is housed, said timepiece movement being held in said case by a damping fastening device, the damping fastening device comprising at least two blades, each blade having two opposite ends fixed, directly or indirectly, to the case and the timepiece movement by fastening elements cooperating with first anchor points of the timepiece movement and second anchor points of the case characterized in that the first anchor points of the timepiece movement are inscribed on a first circle and in that the second anchor points are inscribed on a second circle, the first circle and the second circle being concentric, and in that the first anchor points and the second anchor points have a radial offset with respect to the center of circles C1 and C2,so that the first anchor points are not radially aligned with the second anchor points.

[0013] The fastening device according to the invention makes it possible to connect the watch movement to the case while ensuring a damping effect in order to reduce or control the acceleration suffered by the watch movement during a shock.

[0014] Preferably, the blades are arranged between the watch movement and the case to allow a relative rotational displacement of the watch movement with respect to the case around the axis of rotation passing through the center Z of circles C1, C2, during the elastic deformation of the blades. Thus, the fastening device according to the invention makes it possible to achieve damping by combining an axial movement along the central axis passing through the center Z and a rotational movement around the central axis passing through Z.

[0015] The damping of the watch movement is achieved while ensuring the case remains water-resistant, particularly at the crown stem. It may be necessary to incorporate a disengageable crown stem to allow for the axial and rotational movements of the watch movement without damaging the crown stem or compromising the case's water resistance at the crown stem. The disengagement mechanism can be implemented at the junction between the watch movement and the crown stem, or at the junction between the crown stem and the case.

[0016] Preferably, the control rod has a predetermined and sufficient flexibility to allow the rotation of the watch movement during a shock and / or the axial displacement of the watch movement during the shock.

[0017] In addition to the characteristics mentioned in the preceding paragraph, the timepiece according to the invention may have one or more additional characteristics from among the following, considered individually or in all technically possible combinations: the at least two blades provide damping of the clockwork movement by elastic deformation of said at least two blades; the at least two blades are arranged to allow a relative displacement of the clockwork movement with respect to the case in case of shock, by elastic deformation of said at least two blades causing a rotation of the clockwork movement around the axis of rotation passing through the center of the first circle C1 and the second circle C2; ​​the at least two blades are arranged angularly at an equidistance from each other around the clockwork movement; the at least two blades form a circular repeating pattern around the clockwork movement symmetrical with respect to the axis of rotation passing through the center Z of circles C1 and C2; the at least two blades extend in a tangential, or substantially tangential, direction with respect to the first circle C1;A direction is considered tangential, or substantially tangential, when it forms, at a point on circle C1, an angle of 90° + / - 5° with the radius of circle C1; the at least two blades have identical dimensions and / or mechanical properties; the at least two blades have different dimensions and / or mechanical properties; the at least two blades are made of a material chosen from: steel, elastic steel, superelastic shape memory alloy, amorphous metal, nickel-based superalloy, iron-nickel-based superalloy, cobalt-based superalloy, spring steel, composite materials, or a mixture or combination thereof; the fastening elements include at least one screw; the anchoring points of the watch movement are provided directly on a plate of the watch movement;The watch movement comprises a casing support attached to a mainplate of the watch movement, the anchoring points of the watch movement being provided on the casing support; each blade is formed by a stack of several superimposed blades. Brief description of the figures

[0018] Other features and advantages of the invention will become apparent from the detailed description of the invention which follows with reference to the attached figures, in which: there figure 1 is a perspective and exploded view of a clockwork movement and a fastening device according to one embodiment of the invention; in this embodiment, the fastening device comprises four stacks and a mounting support onto which the clockwork movement is clamped; the figure 2 is a perspective view conforming to the figure 1in an assembled configuration of the clockwork movement and the fastening device; the figure 3 is a perspective view of the whole, illustrated in the figure 2 , presented above a housing in a watch case; the figure 4 is a top view of a timepiece comprising the time movement fitted into the case via the fastening device according to the invention.

[0019] For clarity, identical or similar elements of the different embodiments are identified by identical reference symbols across all figures. Detailed description of the invention

[0020] In relation to figures 1, 2 , 3 and 4 , a fixing device 10 of a clock movement 2 is described, arranged to hold said clock movement 2 in a box 4 of a clock part 1.

[0021] The fastening device 10 according to the invention allows the watch movement 2 to be connected to the case 4 while also providing shock absorption for the watch movement 2 in the event of an impact. In particular, the fastening device 10 according to the invention allows the acceleration experienced by the watch movement 2 to be reduced or controlled during an impact.

[0022] According to the embodiment shown, the mounting device 10 comprises a casing support 5 to which the watch movement 2 is secured, for example, by retaining flanges 51. The casing support 5 is, for example, a casing ring. The casing support 5 is an optional element facilitating the casing of the watch movement 2. However, according to the invention, the watch movement 2 can also be directly cased into the case 4 without the use of an intermediate casing support 5 as shown.

[0023] The fastening device 10 according to the invention comprises at least two blades 3 providing the function of a clamp for the casing of the watch movement and of damping the watch movement during shocks.

[0024] In the example shown, the fastening device 10 comprises four blades 3. However, the fastening device 10 may comprise at least two blades 3, and for example up to six blades 3.

[0025] The different blades 3 of the fastening device 10 may have different dimensions and / or mechanical properties, for example in terms of width and / or thickness and / or Young's modulus.

[0026] The different blades 3 of the fastening device 10 may have identical dimensions and / or mechanical properties.

[0027] In the example shown in figures 1 to 4 , the 3 blades are of identical dimensions.

[0028] The number of blades 3 will be chosen according to the damping, and the desired travel of the watch movement relative to the case 4 for a given shock.

[0029] Preferably, the material of the blades 3 is chosen from the following list: steel, elastic steel, super-elastic shape memory alloy, amorphous metal, nickel-based superalloy, iron-nickel-based superalloy, cobalt-based superalloy, spring steel, composite materials, or a mixture or combination thereof.

[0030] Preferably, the blades 3 are made of a super-elastic shape memory material, for example in a nickel titanium alloy, such as Nitinol.

[0031] Nitinol is a superelastic and shape-memory alloy. The composition (i.e., the percentage of nickel and titanium) of Nitinol is chosen so that within a temperature range of use for watch parts (for example, from -10°C to 50°C), Nitinol is in the austenitic phase, therefore superelastic.

[0032] In this document, "superelastic alloy" means an alloy whose elastic limit deformation is greater than 2%, or even greater than 5%, or even greater than 8%.

[0033] For example, blades 3 may have one or more of the following characteristics: thickness between 0.2 and 2 mm, width between 2 and 6 mm, and length between 8 and 25 mm.

[0034] Each blade 3 has two opposite ends, a first end of the case 3c and a second end of the movement 3d. Each end 3c, 3d has an axial or cylindrical hole arranged for the passage of fixing elements 7 ensuring the attachment of the blade 3 respectively to the case 4 and to the watch movement 2, via the casing support 5 in the event of a casing support, so as to fit the watch movement 2 into the case 4.

[0035] The fixing elements 7 are configured to pass through the hole provided at the ends 3c, 3d of the blades 3 and to cooperate with first anchor points 8a arranged on the casing support 5 (or directly on the plate 9 of the watch movement 2 in the absence of casing support 5) and second anchor points 8b arranged on the case 4.

[0036] For example, the fasteners 7 are screws whose threaded body is arranged to pass through the holes in the ends of the blades 3, and the anchor points 8a, 8b are tapped holes configured to receive the threaded bodies of the screws.

[0037] The ends 3c, 3d of the blades 3 are thus rigidly and reversibly secured by screwing onto the casing support 5 (or onto the plate 9 of the watch movement 2) and onto the case 4. The blades 3 can also be secured by other equivalent means known to those skilled in the art.

[0038] According to the invention, the first anchor points 8a of the clock movement are inscribed on a first circle C1 and the second anchor points 8b are inscribed on a second circle C2, the first circle C1 and the second circle C2 being concentric, with center Z.

[0039] Preferably, the arrangement of the anchor points 8a, 8b between the watch movement 2 and the case 4 is arranged so that the blades 3 can generate a relative rotational displacement of the watch movement 2 with respect to the case 4 around the axis of rotation passing through the center Z, during the elastic deformation of the blades 3. Thus, the fixing device 10 according to the invention makes it possible to combine an axial movement along the axis passing through the center Z and a rotational movement during the elastic deformation of the blades 3.

[0040] The first anchor points 8a and the second anchor points 8b have a radial offset from the center of circles C1 and C2, so that the first anchor points are not radially aligned with the second anchor points.

[0041] Preferably, the blades 3 are arranged angularly at equidistant intervals from each other around the clockwork movement 2.

[0042] Preferably, the different blades 3 form a circular repeating pattern around the clockwork movement 2, preferably symmetrical with respect to the axis of rotation passing through the center Z of the circles C1 and C2.

[0043] Preferably, the blades 3 are arranged so as to extend in a direction tangent to the first circle C1.

[0044] With reference to figures 3 and 4 , once the blades 3 are fixed to the clock movement 2, either directly to the plate 9 or via the casing support 5, the assembly formed by the clock movement 2 and the blades 3 is inserted into a housing in the case of the case 4.

[0045] According to the example shown, the box 4 has surfaces to receive the ends of the box 3c of the blades 3. Preferably, the anchoring points 8b of the box 4 are located at these surfaces. Naturally, the box 4 has at least as many surfaces as there are blades 3 for attaching the watch movement 2.

[0046] The proposed arrangement is therefore compact, reliable, minimizing movement while ensuring damping of the watch movement during shocks in order to protect the watch movement.

[0047] Furthermore, the fastening device according to the invention makes it possible to avoid any loss of attachment of the watch movement in the case during an impact.

[0048] According to one embodiment, each blade 3 of the damping fastening device 10 is formed by a stack of several superimposed blades.

[0049] Preferably, the fastening device may include one or more of the following manufacturing steps: waterjet cutting, three-axis machining, machining, turning, laser cutting, stamping.

[0050] The invention is described above by way of example. It is understood that a person skilled in the art is able to carry out different embodiments of the invention without departing from the scope of the invention.

Claims

1. Timepiece (1) comprising a case (4) in which a timepiece movement (2) is housed, said timepiece movement (2) being held in said case (4) by a damping fastening device (10), the damping fastening device (10) comprising at least two blades (3), each blade (3) having two opposite ends (3c, 3d) fixed, directly or indirectly, to the case (4) and to the timepiece movement (2) by fastening elements (7) cooperating with first anchor points (8a) of the timepiece movement (2) and second anchor points (8b) of the case (4) characterized in that the first anchor points (8a) of the clockwork movement are inscribed on a first circle (C1) and in that the second anchor points (8b) are inscribed on a second circle (C2), the first circle (C1) and the second circle (C2) being concentric, and in thatthe first anchor points (8a) and the second anchor points (8b) are not radially aligned.

2. Timepiece (1) according to the preceding claim, characterized in that said at least two blades (3) ensure damping of the clockwork movement by elastic deformation of said at least two blades (3).

3. Timepiece (1) according to any one of the preceding claims, characterized in that said at least two blades are arranged to allow a relative displacement of the clock movement (2) with respect to the case (4) in case of shock, by elastic deformation of said at least two blades (3a, 3b) causing a rotation of the clock movement (2) around an axis of rotation passing through the center (Z) of the first circle (C1) and the second circle (C2).

4. Timepiece (1) according to any one of the preceding claims, characterized in thatsaid at least two blades (3) are arranged angularly at equidistance from each other around the clockwork movement (2).

5. Timepiece (1) according to any one of claims 3 to 4, characterized in that said at least two blades (3) form a circular repeating pattern around the clockwork movement (2) symmetrical with respect to the axis of rotation passing through the center (Z) of the circles (C1) and (C2).

6. Timepiece (1) according to any one of the preceding claims, characterized in that said at least two blades (3) extend in a tangential direction with respect to the first circle (C1).

7. Timepiece (1) according to any one of the preceding claims, characterized in that said at least two blades (3) have identical dimensions and / or mechanical properties.

8. Timepiece (1) according to any one of claims 1 to 5, characterized in thatsaid at least two blades (3) have different dimensions and / or mechanical properties.

9. Timepiece (1) according to any one of the preceding claims, characterized in that said at least two blades (3) are made of a material selected from: steel, elastic steel, super-elastic shape memory alloy, amorphous metal, nickel-based superalloy, iron-nickel-based superalloy, cobalt-based superalloy, spring steel, composite materials, or a mixture or combination thereof.

10. Timepiece (1) according to any one of the preceding claims, characterized in that the fasteners (7) include at least one screw.

11. Timepiece (1) according to any one of the preceding claims, characterized in that the anchoring points (8a) of the clock movement (2) are provided directly on a plate (9) of the clock movement (2).

12. Timepiece (1) according to any one of claims 1 to 11, characterized in that the watch movement (2) includes a casing support (5) attached to a plate (9) of the watch movement (2), the anchoring points (8a) of the watch movement (2) being provided on the casing support (5).

13. Timepiece (1) according to any one of the preceding claims, characterized in that Each blade (3) is formed by a stack of several superimposed blades.

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