Watch case with rotating bezel

Abstract

The invention relates to a watch case (1) comprising a case middle (2) and a bezel (3) mounted to rotate about an axis A relative to the case middle (2). The watch case (1) comprises n pads (18), with n ≥ 2, arranged between the case middle (2) and the bezel (3) substantially perpendicular to the axis A. These pads (18) are mounted on the case middle (2) and are associated with elastic elements (19) carried by the case middle (2) and arranged to press the pads (18) against the bezel (3). The invention also relates to a watch comprising such a watch case (1).

Description

[0001] The present invention relates to a watch case comprising a case middle and a bezel mounted to rotate relative to the case middle around an axis.

[0002] The invention also relates to a watch, typically a wristwatch or a pocket watch, comprising such a watch case.

[0003] We know of many devices for watch cases with rotating bezels. They mainly aim to simplify the installation of such a bezel and to a lesser extent to improve the sensations perceived by the user during the rotation of the bezel, in particular by separating the indexing (or notching) function of the bezel from the function managing the value of the friction torque of the bezel in relation to the case.

[0004] The perceived quality that the wearer of the watch should experience when rotating the bezel depends largely on the bezel's stability on the case, as well as the intensity and consistency of the torque required to overcome friction. Therefore, it would be beneficial to be able to improve the bezel's stability on the case and adjust the intensity of the friction force opposing its rotation to enhance the user experience.

[0005] Furthermore, the frictional forces involved in rotating the bezel on the case are subject to significant variations and therefore cause dispersion between individual watches. Improving the adjustment of these frictional forces thus also has the advantage of neutralizing this dispersion between watches.

[0006] Patent application EP 2 624 076 describes a watch with a rotating bezel comprising a ratchet system for indexing the bezel and a braking system for adjusting the friction torque for rotating the bezel independently of the ratchet spring force. The forces generated by these two systems are independent. The braking system includes a braking ring pressed against a toothed section of the bezel by a set of springs. This ring is drilled to allow passage of the ratchet, which is carried by the case and cooperates with the bezel teeth for indexing. Thus, while the elastic restoring forces governing the indexing of the bezel and the torque required to rotate it are independent, the components of these systems are interdependent. Furthermore, the means for adjusting the friction torque during bezel rotation are limited.In addition, such a braking ring occupies the entire circumference of the watch case, which can make it difficult to fit certain elements, for example push buttons in a chronograph watch or a winding lock in a minute repeater watch.

[0007] In accordance with the foregoing, an object of the present invention is to provide a rotating bezel watch case in which the stability of the bezel on the case body and the homogeneity of the friction torque are improved and in which it is possible to adjust this torque individually in each example, in a relatively simple way.

[0008] Another objective of the invention is to limit the space occupied by the means for adjusting the friction torque.

[0009] The present document proposes for this purpose a watch case according to claim 1.

[0010] According to the invention, the watch case comprises n pads, with n ≥ 2, arranged between the case middle and the bezel, said pads being mounted on the case middle and being associated with elastic elements carried by the case middle and arranged to press the pads against the bezel.

[0011] It will be understood that the pads (called braking pads) are the source of most of the friction force (in other words, the braking force) which opposes the rotation of the rotating telescope around its axis A. It is possible to increase or decrease the intensity of this braking by changing the material of the pads, by increasing / decreasing their surface area and / or by changing the strength of the elastic elements (springs).

[0012] Each pad is preferably mounted in a recess in the case, each recess opening between the case and the bezel. Advantageously, the elastic elements associated with the pads are mounted inside the recesses. These elastic elements are typically springs, preferably helical springs. Furthermore, the pads are typically arranged substantially perpendicular to axis A.

[0013] In the context of the present invention, the skates are of free shape, for example, square, rectangular, or arc-shaped, preferably arc-shaped. They are preferably arranged on the same circle C centered on axis A. They typically extend over n respective angles whose sum is between 5° and 210°, preferably between 15° and 180°, preferably between 30° and 90°, and preferably between 40° and 80°. They are preferably uniformly distributed around axis A.

[0014] Advantageously, the two ends of the arc-shaped pads are thinned in the direction of axis A. They are preferably entirely housed in the recesses that accommodate the pads so as to limit unwanted friction between the edges of the pads and the teeth of the telescope.

[0015] The effective surface area of ​​a pad can be defined as the portion of its surface that bears against the bezel and contributes to its braking. Typically, the portions of the pads corresponding to the tapered ends do not define an effective surface area. Preferably, the effective surfaces of the watch case pads according to the invention extend along circle C at angles whose sum is at least 5°, preferably at least 15°.

[0016] The watchmaker can use different pads of the same length, each with a different effective surface area, to optimize the stability of the bezel on the case and the friction forces involved in its rotation. They can also choose to mount pads with different effective surfaces on the same watch case, for example, to compensate for an imbalance.

[0017] The watch case according to the invention preferably comprises first and second indexing structures arranged to cooperate in such a way as to index the angular positions of the bezel relative to the case.

[0018] If applicable, the first indexing structure typically comprises edge teeth, preferably unidirectional, fixed to the bezel. The second indexing structure typically comprises a ratchet. Ideally, it is located on the C-ring, between two carriages, and is therefore completely independent of the carriages.

[0019] In the context of the present invention, the bezel is typically retained axially on the case by stop means attached to the case and arranged to prevent axial movement of the bezel relative to the case.

[0020] Advantageously, the stop means attached to the case and arranged to prevent axial movement of the bezel include, on the one hand, removable assembly elements which are accessible from outside the watch case and which extend radially in the case wall, and on the other hand include at least one intermediate assembly piece located in a housing formed in the case wall, axially blocked in this housing by the removable assembly elements, blocked in rotation around the axis A and cooperating with the bezel to hold it axially.

[0021] The arrangement in the case of the intermediate assembly piece allows it to be hidden, at least partially, or even made totally invisible, for aesthetic reasons.

[0022] Each intermediate assembly piece typically includes a collar engaged in a groove machined into the inner periphery of the bezel to ensure its axial retention. Alternatively, each intermediate assembly piece may include a groove receiving a protruding portion of the bezel to perform this function.

[0023] In addition, the intermediate assembly piece(s) is preferably in the shape of an arc of a circle extending along the circle C and fixed to the frame by at least two said removable assembly elements.

[0024] According to an advantageous embodiment of the invention, there are two pads (n = 2). In this embodiment, the pads are preferably arranged in diametrically opposite positions. Regardless of the number of pads, they are preferably uniformly distributed around axis A. This aims to balance the forces to maximize the stability of the bezel on the case.

[0025] In an advantageous embodiment of the invention, the watch case according to the invention comprises two removable assembly elements and two pads arranged alternately and uniformly distributed on the circle C.

[0026] The invention also relates to a watch comprising such a watch case.

[0027] Other features and advantages of the present invention will become apparent from the following description, given solely by way of non-limiting example, and made with reference to the accompanying drawings in which: therefigure 1 is an exploded, top view of a watch case with a rotating bezel according to a particular embodiment of the invention; the figure 2 is a top view of part of the watch case illustrated in the figure 1 in which the rotating telescope is not shown; the figure 3 is a perspective cross-sectional view of the watch case portion illustrated in the figure 2 according to the section plan II shown in the figure 2 ; there figure 4 is a cross-sectional view of the watch case portion illustrated in the figure 2 according to the section plan II-II shown in the figure 2 .

[0028] With reference to figures 1 à 4 , a watch case 1 according to a particular embodiment of the invention comprises a case 2 and a rotating bezel 3, mounted to rotate relative to the case 2 around an axis A.

[0029] At 6 o'clock and 12 o'clock, the case 2 has two pairs of lugs 4 in its lower part for attaching a bracelet 5 (shown only at the figure 4 ).

[0030] The upper part of the case 2, surrounded by the rotating bezel 3, constitutes a mount 6 or fixed bezel in which the crystal 7 is typically set (represented only in the figure 4 ). In the example shown, the case 2 is a single piece but it could be in several assembled parts, including for example a main part and the frame 6 assembled to the main part.

[0031] The rotating bezel 3 can be a single piece, as shown, or made of several assembled parts, in particular several coaxial annular parts. It is guided in rotation around the axis A of the watch case 1 by the mount 6.

[0032] The rotating bezel 3 is held axially relative to the case 2 by an assembly device as described in detail in European patent application No. 22163346.4, the description of which is incorporated by reference.

[0033] This assembly device includes removable assembly elements 8, such as screws or dowels, which can be manipulated with a tool from outside the watch case 1, and first and second intermediate assembly pieces 9. The first and second intermediate assembly pieces 9 are located at 6 o'clock and 12 o'clock in recesses 10 formed in the case wall 2 and open at the top. The removable assembly elements 8 extend radially (with respect to axis A) in the case wall 2, accessible from the two lugs 4a. They pass through holes 11 in the case 2 and holes 12 in the intermediate assembly pieces 9 to terminate in holes 13 in the case wall 2. They thus axially lock the intermediate assembly pieces 9. The intermediate assembly parts 9 are also prevented from rotating around the axis A by the removable assembly elements 8 and / or by the housings 10.

[0034] The intermediate assembly parts 9 include a collar 14 engaged in a groove 15 formed in the inner periphery of the bezel 3, thus allowing the bezel 3 to be held axially without preventing its rotation. The collar 14 acts as a stop, integral with the case and arranged to prevent axial movement of the bezel relative to the case.

[0035] Such an assembly device offers numerous advantages. It allows for a robust and shock-resistant assembly of the bezel 3 onto the case 2, good control of the axial play between the case 2 and the bezel 3, and allows for easy assembly and disassembly of these elements.

[0036] The watch case 1 also includes indexing structures to index the angular positions of the bezel 3 relative to the case 2.

[0037] The rotating bezel 3 includes a unidirectional edge toothed section 3a constituting the first indexing structure. This toothed section 3a is arranged to cooperate with a pawl 16 mounted on the case 2. The pawl 16 is pressed by a spring 17 in the direction of axis A against the toothed section 3a. Thus, the pawl 16 and the toothed section 3a cooperate to index the rotating bezel 3, each gap between two successive teeth defining a position in cooperation with the pawl 16. In the illustrated example, each tooth of the unidirectional toothed section 3a has two flat flanks that are connected by a vertex extending in a plane substantially perpendicular to axis A.

[0038] Preferably, the pawl 16 and the spring 17 are housed in a recess (not shown), typically a groove, in the case 2. This is typically a blind cylindrical bore, in which the pawl 16 slides freely. The spring 17 bears against the bottom of the recess to push the pawl 16 against the rotating bezel 3.

[0039] The pawl 16 is designed to cooperate with the unidirectional toothing 3a to allow its rotation in only one direction. It typically includes an inclined plane 16a intended to slide against the teeth of the unidirectional toothing 3a when the rotating bezel 3 is pivoted counterclockwise (in top view, as illustrated in the figure 1 ) and a portion 16b forming a stop when the wearer of the watch attempts to rotate the rotating bezel 3 clockwise (in top view), only counter-clockwise rotation being possible here.

[0040] The ratchet 16 is preferably positioned close to an intermediate assembly part 9 so that it does not interfere or interferes very little with the stability of the scope 3 on the case 2.

[0041] In order to achieve the purpose of the invention, the watch case 1 includes, between the case middle 2 and the rotating bezel 3, two pads 18 (or plates), mounted on the case middle 2, and associated with pairs of springs 19 which press them against the unidirectional toothing 3a of the bezel 3.

[0042] The pads 18 and the associated springs 19 ensure a friction braking function between the pads 18 and the rotating bezel 3 during the rotation of the rotating bezel 3 on the case 2. They guarantee, among other things, the existence of a torque of determined intensity resisting the rotation of the rotating bezel 3 on the case 2.

[0043] Each skate 18 is mounted with some play in the direction of axis A, thus allowing the springs 19 to compress and extend parallel to axis A. The springs 19 are helical compression springs. They are typically made of steel, but any other suitable material is acceptable.

[0044] The pads 18 typically bear against the crests of the teeth 3a. In the illustrated example, these are flat surfaces. However, in some variations, the teeth of the teeth 3a could have a crest forming an edge or a rounded shape. In this case, the pads 18 would bear against all of these edges or rounded shapes.

[0045] Advantageously, each skate 18 is housed in a housing 20, typically a recess, which is part of the frame 2 and which opens between the frame 2 and the bezel 3. Each housing 20 includes blind holes 21 inside which the springs 19 are mounted.

[0046] The pads 18 are shaped like circular arcs. They are arranged on a single circle C centered on axis A and extend over angles α1 and α2 respectively, the sum of which is between 5° and 210°, preferably between 15° and 180°, preferably between 30° and 90°, and preferably again between 40° and 80°. In the illustrated example, α1 and α2 are equal and measure approximately 33°. Thus, they occupy a limited space and leave the periphery of the case 2 available for other uses. Here, typically, for the installation of the intermediate assembly parts 9, which ensure the axial retention of the bezel 3 on the case 2, and of the ratchet 16, which indexes the bezel 3 on the case 2.

[0047] Advantageously, the two ends of the circular-shaped pads 18 are tapered in the direction of axis A. They are preferably fully housed in the recesses 20 that accommodate the pads 18 so as to limit unwanted friction between the edges of the pads and the teeth of the telescope 3. This is particularly visible at the figure 3 .

[0048] The effective surface of a pad 18 can be defined as the portion of its surface that bears against the bezel 3 (here, against the teeth 3a) and contributes to its braking. Typically, the portions of the pads 18 corresponding to the thinned ends mentioned previously do not define an effective surface.

[0049] Preferably, the useful surfaces of the skates 18 extend along the circle C at angles θ1 and θ2 whose sum is at least 5°, preferably at least 15°, preferably at least 23°. In the illustrated example, θ1 and θ2 are equal and measure approximately 25°.

[0050] Advantageously, the pads 18 can have different usable surfaces to best adjust the stability of the scope on the case, for example to compensate for an imbalance such as that potentially caused by the ratchet 16.

[0051] The 18 pads are preferably made of polymer, for example PEAK, polytetrafluoroethylene (PTFE) or titanium. Their shapes and dimensions are such that it is easy for the watchmaker to make them in other materials depending on the properties he is looking for (friction force or wear resistance for example).

[0052] The watch case 1 typically comprises two pads 18 and two intermediate assembly pieces 9 arranged alternately along circle C. Their distribution around axis A is uniform. By arranging the elements providing friction and axial support on the same circle, space is saved within the watch case. Furthermore, there is still space between the intermediate assembly pieces and the pads to accommodate other components if needed (in addition to the ratchet 16).

[0053] The preceding description focuses on describing a particular embodiment by way of non-limiting illustration, and the invention is not limited to the implementation of certain particular features that have just been described, such as for example the number of pads, the number and type of springs used, the structure of the bezel / case assembly device, the bezel indexing structures on the case or the shapes represented for the different components.

[0054] It should be noted that the watch case according to the invention may include more than two pads, for example three, four or more. Regardless of their number and size, the pads are preferably arranged uniformly around the axis of rotation A along the circle C, for improved stability of the bezel 3.

[0055] It should also be noted that the assembly device for axially retaining the bezel 3 on the case 2 is not restrictive and could be different. The assembly could be achieved, for example, using a bent metal wire or an elastic ring that engages with both a groove in the case and a groove in the bezel. In this case, four locking pads would typically be used.

[0056] The braking function and the intensity of the torque required to rotate the bezel of the watch case according to the invention depend, among other things, on the surface area of ​​the pads in contact with the bezel and the force exerted by the springs pressing these pads against the bezel.

[0057] A simple first way to adjust the friction torque of the bezel on the case is to change the strength of the springs used to press the pads against the bezel.

[0058] Another way to adjust the value of this friction torque is to vary the effective surface area. To do this, the watchmaker can adjust the number and size of the pads. Alternatively, the watchmaker could have sets of pads of the same length but with different effective surfaces, which they could position as needed to adjust the friction piece by piece during the watch assembly, thus achieving a precise adjustment of the friction force opposing the rotation of the bezel.

[0059] Yet another way to adjust the value of this friction torque is to vary the materials used to make the pads.

[0060] The watch case according to the invention therefore allows for simple adjustment, typically piece by piece, of the friction force that opposes the rotation of the bezel.

[0061] The watch case according to the invention also has the advantage of having a braking function (provided by the pads) which is independent of the indexing and anti-reverse function which is managed by the ratchet assembly 16 - spring 17. In such a watch case, the stability of the bezel on the case is dissociated from the ratchet function.

[0062] In addition, the watch case pads according to the invention cushion the shocks of the indexing means, typically the ratchet 16 against the teeth 3a, which also increases the comfort of the watch wearer.

Claims

1. Watch case (1) comprising a case middle (2) and a bezel (3) rotatably mounted relative to the case middle (2) around an axis A, characterized in that it comprises n pads (18), with n ≥ 2, arranged between the case middle (2) and the bezel (3), said pads (18) being mounted on the case middle (2) and being associated with elastic elements (19) carried by the case middle (2) and arranged to press the pads (18) against the bezel (3).

2. Watch case (1) according to claim 1, characterized in that each pad (18) is mounted in a hollow (20) in the case middle (2), each hollow (20) opening between the case middle (2) and the bezel (3).

3. Watch case (1) according to claim 2, characterized in that the elastic elements (19) with which the pads (18) are associated are mounted inside the hollows (21).

4. Watch case (1) according to one of the preceding claims, characterized in thatthe pads (18) are arranged on the same circle C centered on the axis A and extend over n respective angles the sum of which is between 5° and 210°, preferably between 15° and 180°, preferably between 30° and 90°, more preferably between 40° and 80°.

5. Watch case (1) according to claim 4, characterized in that the pads (18) are uniformly distributed around the axis A.

6. Watch case (1) according to claim 4 or 5, characterized in that the pads (18) have useful surfaces, corresponding to the parts of their surface pressed against the bezel (3), said useful surfaces extending along the circle C over angles whose sum is at least 20°.

7. Watch case (1) according to one of claims 4 to 6, characterized in that the ends of each pad (18) are thinned in the direction of axis A.

8. Watch case (1) according to one of the preceding claims, characterized in thatit comprises first (3a) and second (16) indexing structures arranged to cooperate so as to index the angular positions of the bezel (3) relative to the caseband (2).

9. Watch case (1) according to claim 8, characterized in that the first indexing structure comprises an edge toothing (3a), preferably unidirectional, secured to the bezel (3).

10. Watch case (1) according to claim 8 or 9, characterized in that the second indexing structure comprises a ratchet (16).

11. Watch case (1) according to claim 4 and one of claims 8 to 10, characterized in that the second indexing structure (16) is located on the circle C, between two pads (18).

12. Watch case (1) according to one of the preceding claims, characterized in thatthe bezel (3) is held axially on the case (2) by stop means (14) integral with the case (2) and arranged to prevent axial movement of the bezel (3) relative to the case (2).

13. Watch case (1) according to claim 12, characterized in that the stop means secured to the caseband and arranged to prevent axial movement of the bezel comprise, on the one hand, removable assembly elements (8) which are accessible from outside the watch case (1) and which extend radially in the wall of the caseband (2), and on the other hand comprise at least one intermediate assembly part (9) located in a housing (10) formed in the wall of the caseband (2), axially locked in this housing (10) by the removable assembly elements (8), locked in rotation about the axis A and cooperating with the bezel (3) to hold it axially.

14. Watch case (1) according to claim 12 or 13, characterized in that the or each intermediate assembly part (9) is in the shape of an arc of a circle extending along the circle C and fixed to the middle (2) by at least two removable assembly elements (8).

15. Watch case (1) according to claim 13 or 14, characterized in that it comprises two intermediate assembly parts (9) and two pads (18) arranged alternately along the circle C.

16. Watch comprising a watch case (1) according to one of claims 1 to 15.

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