Fastening device for bracelet

Abstract

The invention relates to a device for fastening a bracelet to a watch casing (60), comprising: - a terminal body (10A; 10B) of the bracelet, - at least one mobile fastening element (20) comprising a pivot portion (21) and mounted within the terminal body (10A; 10B) so as to be movable between an engagement position in which the pivot portion (21) is arranged to engage with the casing (60), for example in a bore in a lug of the casing (60), and a retracted position, in which the pivoting portion (21) is arranged so as to disengage from the casing (60) so as to be able to release the terminal body (10A; 10B) from the casing (60), - a lever (30; 30B; 30C), movably mounted in rotation on the terminal body (10A; 10B), - at least one movable cam (22) engaged with the lever (30; 30B; 30C) in order to cause the movable fastening element (20) to pass from the engagement position toward the retracted position during a rotation of the lever (30; 30B; 30C), characterized: - in that the device comprises at least one static cam (40) fixedly mounted on the terminal body (10A; 10B) opposite the movable cam (22) in order to impose an axial movement on the movable cam (22) during its rotation, - and in that the movable cam (22) is formed directly on the movable fastening element (20), and arranged between the lever (30; 30B; 30C) and the static cam (40).

Description

[0001] The present invention generally relates to a bracelet attachment device, intended to attach a bracelet to a timepiece such as a watch.

[0002] Bracelet attachment devices are known in the prior art, such as those presented in documents CH713218A1, EP2047766A2, or JP4754249B2. In these devices, movable elements can be placed in housings located in the lugs of the watch case. However, these systems have the particular disadvantage of requiring complex parts to manufacture which must also be resized according to the lug spacing of the case.

[0003] An aim of the present invention is to address the drawbacks of the prior art documents mentioned above and in particular, first of all, to propose a device for attaching a bracelet to, for example, a watch case, which makes it possible to provide to a certain extent a standardization of the elements of the attachment device and / or the bracelet, without making the manufacturing more complex.

[0004] For this, a first aspect of the invention relates to a device for attaching a bracelet to a watch case, comprising: a terminal body of the bracelet, at least one movable attachment element comprising a pivot part, and mounted in the terminal body to be movable between an engagement position, in which the pivot part is arranged to engage with the case, for example in a bore of a horn of the case, and a retracted position, in which the pivot part is arranged to disengage from the case, so as to be able to release the terminal body from the case, a lever, mounted movable in rotation on the terminal body, at least one movable cam engaged with the lever to move the movable attachment element from the engagement position to the retracted position during a rotation of the lever, characterized: in that the device comprises at least one static cam fixedly mounted on the terminal body opposite the movable cam, to impose an axial movement on the movable cam during its rotation, and in that the movable cam is directly formed on the movable attachment element, and arranged between the lever and the static cam.

[0005] The attachment device according to the above implementation is a quick or reversible attachment device. It is sufficient to operate the lever to engage or disengage the pivot part of the watch case, so as to attach or detach the terminal body, without the aid of an additional tool. In addition, the movable cam is directly formed on the attachment element, which avoids providing it on the lever, which simplifies the manufacture of the lever and thus offers a possibility of standardization. Indeed, it is possible to provide for modifying only the width of the lever in the event of adapting the attachment device to another model of case which would have a different width.

[0006] Advantageously, the movable attachment element is mounted in the terminal body according to a sliding pivot connection.

[0007] Advantageously, the movable attachment element is engaged with the lever in a sliding connection, with preferably the movable attachment element comprising a tenon engaged in a groove of the lever, and more preferably the movable attachment element comprising two tenons each engaged in a groove of the lever. In particular, the tenons are arranged at 180° to each other on a cylinder of the attachment element.

[0008] Advantageously, the static cam is driven into the terminal body.

[0009] Advantageously, the static cam comprises angular indexing means, such as a radial protrusion, arranged to engage with the terminal body, so as to define a predefined angular orientation between the static cam and the terminal body.

[0010] Advantageously, the lever is movable between: an initial rest position in which the movable attachment element is in the engaged position, and an actuating position in which the movable attachment element is in the retracted position,

[0011] Advantageously, the terminal body comprises: a housing arranged to accommodate the lever in the initial rest position, and a stop arranged to define the maximum actuation position of the lever.

[0012] Advantageously, the attachment device comprises return means such as a spring, arranged to exert a thrust force on the movable attachment element towards the engagement position.

[0013] Advantageously, one of the movable cam - static cam assembly has a cam track with a rest portion such as a notch, the other of the movable cam - static cam assembly has a cam track with a peak or protrusion, and the movable attachment element is in an engaging position when the peak or protrusion is engaged with or positioned at the rest portion.

[0014] Advantageously, the rest portion is adjacent to a cam slope, so that the return means maintain the movable attachment element in a stable position in the engaged position, and the lever in the initial rest position.

[0015] Advantageously, the pivot part of the movable attachment element passes through the static cam.

[0016] Advantageously, the pivot part is mounted in a pivot connection in the static cam.

[0017] Advantageously, the attachment device comprises: two movable attachment elements, two static cams, in which: the two movable attachment elements are arranged on either side of the lever, the two static cams are each mounted fixed on a side of the terminal body, the pivot parts of each movable attachment element each pass through a static cam so as to: ∘ project from the static cam and / or the terminal body to be able to engage with the housing, for example in a bore of a horn of the housing, when each movable attachment element is in the engagement position, ∘ be retracted into the static cam and / or into the terminal body to release the terminal body from the housing, when each movable attachment element is in the retracted position.

[0018] A second aspect of the invention relates to a watch strap comprising at least one attachment device according to the first aspect.

[0019] A third aspect of the invention relates to a wristwatch, comprising at least one attachment device according to the first aspect.

[0020] Other characteristics and advantages of the present invention will appear more clearly on reading the following detailed description of an embodiment of the invention given by way of non-limiting example and illustrated by the appended drawings, in which: there figure 1 represents a perspective view of a first embodiment of a fastening device according to the invention; the figure 2 represents a perspective view of a fastening element and a static cam of the fastening device of the figure 1 ; there figure 3 represents a perspective view of a lever engaging the attachment element with the static cam of the attachment device of the figure 1 there figure 4 represents a section of the attachment device of the figure 1 , with the attachment members in an engaging position for attaching a bracelet terminal body with a watch case; the figure 5 represents a section of the attachment device of the figure 1 , with the attachment members in a retracted position for releasing a bracelet end body from a watch case; the figure 6 represents a second embodiment of a fastening device comprising a lever produced according to an alternative of the lever of the fastening device of the figure 1 ; there figure 7 represents a fastening device according to a third embodiment; the figure 8 represents the attachment device of the figure 7 integrated into a flexible bracelet.

[0021] There figure 1 represents a bracelet attachment device according to a first embodiment of the invention. The attachment device according to this embodiment comprises in particular two attachment elements 20 mounted in a terminal body 10A of the bracelet and in a lever 30 articulated in rotation on the terminal body 10A. In this first embodiment, the terminal body 10A is typically a terminal link of a link bracelet, that is to say comprising a plurality of links articulated to each other.

[0022] In addition, two static cams 40 are provided on each side of the terminal body 10A, and a spring 50 is mounted between the two fastening elements 20, in a bore 32 of the lever 30, as are a portion of the fastening elements 20 as shown in FIG. figure 4 .

[0023] Generally, the attachment device is provided to move the two attachment elements 20 between a retracted position ( figure 5 ) in which the terminal body 10A is free relative to the watch case 60 (shown in fine dot-and-dash lines on the right only) and an engagement position ( figure 4 ) in which the terminal body 10A, via the attachment elements, is attached to the watch case 60 (still shown in fine dot-dash lines on the right only).

[0024] Indeed, the attachment elements 20 can be retracted into the terminal body ( figure 5 ), or have a pivot part 21 projecting or protruding relative to the terminal body 10A ( figure 4 ).

[0025] In detail, and as shown in the figure 2 , each attachment element 20 comprises a pivot part 21, a movable cam 22 comprising two movable cam tracks, a guide part 26, a tenon 23 and a free end 25. The two movable cam tracks or movable cam 22 are separated by notches 24 opposite at 180°.

[0026] Opposite each attachment element 20, provision is made to fixedly mount static cams 40 in the terminal body 10A, each comprising a base 41, two static cam tracks 42, and a protrusion 43, which may otherwise be called an ear. Each static cam 40 is fixedly mounted or driven into a bore 11 of the terminal body 10A, and the protrusions 43 make it possible to angularly position the static cams 40 relative to the terminal body 10A.

[0027] There figure 2 shows a particular angular position between the attachment element 20 and the static cam 40: the vertices 44 of the static cam tracks 42 are aligned with the notches 24 of the attachment element 20. In this position, and under the effect of the spring 50, it is understood that the movable cam tracks or movable cam 22 and static cam tracks 42 will fit into each other, and the pivot part 21 passes through the static cam 40, to exit and protrude, as clearly shown figure 4 .

[0028] Starting from the figure 2 , if the attachment element 20 is pivoted by 90°, then the vertices 44 will be opposite the vertices of the movable cam tracks or movable cam 22, so that the attachment element 20 will move away from the static cam 40, with the effect that the pivot part 21 enters the static cam 40, and does not protrude from it, as shown in figure 5 .

[0029] This kinematics is made possible by an action exerted by the user on the lever 30. The latter therefore comprises a bore 32, provided with a groove 33, visible figure 1 and above all figure 3 The tenon 23 of the attachment element 20 is engaged in the groove 33, so that the connection between these two parts is a sliding connection, as shown by the double arrow in the figure 3 .

[0030] Consequently, and since the lever 30 is mounted to be able to rotate on the terminal body 10A, a rotation of the lever 30 will also cause the attachment elements 20 to rotate, each of which faces a static cam 40. Due to the force exerted by the spring 50, the movable cam tracks or movable cam 22 and static cam tracks 42 will cooperate to cause, due to the relative rotational movement, an axial movement in the lever 30 of each attachment element 20.

[0031] As shown in the figure 1 , the terminal body 10A has a housing 12 in which the lever 30 can be housed when it is in an initial rest position, which corresponds to the figure 4 , where the fastening elements 20 are in the engaged position. In this position, the spring 50 therefore presses on the fastening elements 20, with the tops 44 of the static cam tracks 42 aligned with the notches 24 of the fastening element 20.

[0032] This position is a stable rest position, because to exit it, the spring 50 must be stressed. In other words, due to the engagement of the vertices 44 of the static cam tracks 42 aligned with the notches 24 of the attachment element 20, the spring 50 maintains the lever 30 in the initial rest position.

[0033] To actuate the mechanism, a user can act on a free end 31 of the lever 30, to pivot it out of the housing 12 and bring the lever 30 into mechanical abutment on the terminal body, after a rotation of 90° for example. Thus, the tops 44 of the static cam tracks 42 are brought to be opposite the tops of the movable cam tracks or movable cam 22, which causes the attachment elements 20 to "retract" into the lever 30 to retract them. The user can detach and release the terminal body from the watch case 60 because the pivot parts 21 no longer project relative to the terminal body 10A.

[0034] As the figures 4 et 5 , it can be noted that the lever 30 is mounted in rotation on the terminal body 10A, via the attachment elements 20 and the static cams 40. Indeed, each attachment element 20 has a guide part 26 mounted in the bore 32 of the lever 30, and the pivot part 21 of each attachment element 20 being mounted in a bore of each static cam 40, the latter being driven into the terminal body 10A.

[0035] There figure 6 represents a second embodiment (a manufacturing variant of the first embodiment) with a lever 30B which still comprises a bore 32, but two grooves 33, so that the attachment elements 20B can have two tenons 23 opposite at 180°. All the rest of the attachment device being identical to the attachment device of the figure 1 , this will not be described again.

[0036] There figure 7 represents a third embodiment of a fastening device, with a terminal body 10B which has a cylindrical external shape, to be able to form an insert to be integrated into the end of a flexible bracelet, made of leather or polymer for example.

[0037] The terminal body 10B has an internal bore which accommodates the static cams 40 and the fastening elements 20 (including the figures 7 And 8 show the pivot part 21 protruding from the static cam 40) identical to the first embodiment: the static cams 40 are driven on each side into the terminal body 10B, so as to trap the attachment elements 20 and the spring (not visible).

[0038] As in the first embodiment, the terminal body 10B has a central housing in which the lever 30C is positioned, the latter being mounted in rotation relative to the terminal body 10B by means of the attachment elements 20 and the static cams (the assembly is identical to that of the figures 4 et 5 described above).

[0039] The terminal body 10B forms, in this third embodiment, an insert to be integrated at the end of a flexible bracelet 100. As shown in the figure 8 , the terminal body 10B is mounted at the end of the flexible bracelet 100, by techniques known to those skilled in the art, such as gluing or sewing. A central passage slot for the lever 30C is also provided at the end of the flexible bracelet 100 in order to allow a user to actuate the lever 30C to pivot it and detach / attach the flexible bracelet 100 to a watch case.

[0040] It appears that the static cams 40 are parts added and driven into the terminal body, that the attachment elements 20 carry the moving cam tracks or moving cam 22, so that all these elements are independent parts which can be easily used for bracelets of different sizes, or of special external shapes, which allows these elements to be used for several models. Thus, the most complex parts to be machined are identical regardless of the dimensions of the lug space of the case, the static cams 40 and the attachment elements 20 are identical. The components specific to the specific width are the terminal body 10B, the internal spring and the lever 30C, which are less complicated parts to machine. The ranges or the manufacturing settings of the most complex parts are therefore not changed.

[0041] Furthermore, the assembly does not require prior fixing of the lever 30, 30B, 30C on the terminal body 10A or 10B, since the pivot connection between these two parts is provided by the attachment device itself: manufacturing is faster. In particular, on each side of the terminal body, a static cam 40 is driven (or force-fitted) into the terminal body 10A or 10B and comprises a through hole, which receives and guides the pivot part 21 of an attachment element 20. Each attachment element 20 also comprises a guide part 26 housed in the bore 32 of the lever 30, 30B or 30C, so that each guide element 20 provides the mechanical connection between the terminal body 10A or 10B and the lever 30, 30B or 30C.

[0042] It will be understood that various modifications and / or improvements obvious to those skilled in the art may be made to the different embodiments of the invention described in the present description without departing from the scope of the invention defined by the appended claims. In particular, reference is made to a tight or driven mounting of each static cam on the terminal body, but it is possible to envisage mounting by screwing or by elastic interlocking (clipping) for example.

Claims

1. A device for fastening a wristlet to a watch case (60), comprising: - an end body (10A; 10B) of the wristlet, - at least one movable fastening element (20) comprising a pivot part (21) and mounted in the end body (10A; 10B) to be movable between an engagement position in which the pivot part (21) is arranged to engage with the case (60) for example in a bore of a horn of the case (60), and a retracted position in which the pivot part (21) is arranged to disengage from the case (60) so as to be able to release the end body (10A; 10B) from the case (60), - a lever (30; 30B; 30C) movably mounted in rotation on the end body (10A; 10B), - at least one movable cam (22) engaged with the lever (30; 30B; 30C) to switch the movable fastening element (20) from the engagement position to the retracted position during a rotation of the lever (30; 30B; 30C), characterized: - in that the device comprises at least one static cam (40) fixedly mounted on the end body (10A; 10B) facing the movable cam (22), to impose an axial movement on the movable cam (22) during its rotation, - and in that the movable cam (22) is directly formed on the movable fastening element (20), and arranged between the lever (30; 30B; 30C) and the static cam (40).

2. The fastening device according to claim 1, wherein the movable fastening element (20) is mounted in the end body (10A; 10B) in a sliding pivot connection.

3. The fastening device according to any of claims 1 to 2, wherein the movable fastening element (20) is engaged with the lever (30; 30B; 30C) in a slide connection, preferably with the movable fastening element (20) comprising a stud (23) engaged in a groove (33) of the lever (30; 30B; 30C), and more preferably the movable fastening element (20) comprising two studs (23) each engaged in a groove (33) of the lever (30; 30B; 30C).

4. The fastening device according to any of claims 1 to 3, wherein the static cam (40) is driven into the end body (10A; 10B).

5. The fastening device according to any of claims 1 to 4, wherein the static cam (40) comprises angular indexing means, such as a radial outgrowth (43), arranged to engage with the body end (10A; 10B), so as to define a predefined angular orientation between the static cam (40) and the end body (10A; 10B).

6. The fastening device according to any of claims 1 to 5, wherein: - the lever (30; 30B; 30C) is movable between: - an initial rest position in which the movable fastening element (20) is in the engagement position, and - an actuation position in which the movable fastening element (20) is in the retracted position, - the end body (10A; 10B) comprises: - a housing (12) arranged to accommodate the lever (30; 30B; 30C) in the initial rest position, and - a stop arranged to define the maximally actuated position of the lever (30; 30B; 30C).

7. The fastening device according to any of claims 1 to 6, comprising return means such as a spring (50), arranged to exert a push force on the movable fastening element (20) towards the engagement position.

8. The fastening device according to any of claims 1 to 7, wherein - one of the movable cam (22) - static cam (40) assembly has a cam track with a rest portion such as a notch (24), - the other of the movable cam (22) - static cam (40) assembly has a cam track with a top (44) or a protrusion, and wherein the movable fastening element (20) is in the engagement position when the top (44) or the protrusion is engaged with or positioned at the level of the rest portion.

9. The fastening device according to claim 8, when dependent on claim 7 and claim 6, wherein the rest portion is adjacent to a cam slope, so that the return means maintains in a stable position the movable fastening element (20) in the engagement position, and the lever (30; 30B; 30C) in the initial rest position.

10. The fastening device according to any of claims 1 to 9, wherein the pivot part (21) of the movable fastening element (20) passes through the static cam (40).

11. The fastening device according to claim 10, wherein the pivot part (21) is mounted in pivot connection in the static cam (40).

12. The fastening device according to any of claims 1 to 11, comprising: - two movable fastening elements (20), - two static cams (40), wherein: • the two movable fastening elements (20) are arranged on either side of the lever (30; 30B; 30C), • the two static cams (40) are each fixedly mounted on a flank of the end body (10A; 10B), • the pivot parts (21) of each movable fastening element (20) each pass through a static cam (40) so as to: ∘ project from the static cam (40) and / or from the end body (10A; 10B) in order to be able to engage with the case (60), for example in a bore of a horn of the case (60), when each movable fastening element (20) is in the engagement position, o be retracted in the static cam (40) and / or in the end body (10A; 10B) to release the end body (10A; 10B) from the case (60), when each movable fastening element (20) is in the retracted position.

13. A watch wristlet comprising at least one fastening device according to any of claims 1 to 12.

14. A wristwatch, comprising at least one fastening device according to any of claims 1 to 12.

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