The present invention relates to a clasp for a wristlet comprising at least one locking device. It relates also to a wristlet and a wristwatch as such comprising such a clasp.
There are multiple solutions for hooking the two lengths of a watch wristlet around the wrist of its wearer. The first solution is simple and consists in providing the ends of each length with cooperation means, in the form, for example, of a simple loop and a tongue on the one hand cooperating with holes on the other hand. Such a solution presents the drawback that, when the cooperation means are opened, the two lengths of the wristlet are immediately separated, leading to the risk of the wristwatch being dropped.
To mitigate this drawback, another solution consists in providing an intermediate element of clasp type, disposed between the two wristlet lengths, which always remains secured to the ends of these two lengths. Such a clasp occupies two positions: a closed position, provided for the wearing of the watch, in which the wristlet and the clasp extend around the perimeter of the wrist by having an overall length allowing the wristwatch to be worn, and an open position which allows the length of the wristlet and of the clasp to be increased, by separating the two ends of the two lengths of the wristlet without detaching them from the clasp, to allow the hand to pass through the watch to be removed. In this open configuration of the clasp, the two lengths of the wristlet are not separated, which minimizes the risk of the watch being dropped.
A clasp generally comprises two or three foldable blades, which are at least partly folded back on themselves in closed position and unfolded in the open position of the clasp. Locking and unlocking mechanisms are used to guarantee that the closed position is stably maintained. For example, the document EP1654950 describes such a locking solution.
However, there is a need for another locking solution for a wristlet clasp. Thus, the invention seeks to achieve all or some of the following objects.
A first object of the invention consists in proposing a locking solution for a wristlet clasp that is reliable and robust.
A second object of the invention consists in proposing a locking solution for a wristlet clasp that has minimal bulk.
A third object of the invention consists in proposing a locking solution for a wristlet clasp that is compatible with an esthetic search for the appearance of the clasp.
To this end, the invention relies on a locking device for a wristlet clasp, wherein it comprises an actuation lever intended for the actuation of the locking device by a user, a locking element capable of cooperating with a complementary hooking element and wherein it comprises an intermediate element linked on the one hand to the locking element by a first link device and linked on the other hand to the actuation lever by a second link device, at least one of these two link devices being provided with at least two degrees of freedom.
The invention is specifically defined by the claims.
These objects, features and advantages of the present invention will be explained in detail in the following description of a particular embodiment given in a nonlimiting manner in relation to the attached figures in which:
To simplify the description, use will be made by convention of the terms “longitudinal direction” for the lengthwise direction of a clasp or of a wristlet length, and “transverse direction” for the right-angled direction in the plane of a clasp (more specifically, the plane of a blade or a cover of the clasp), considering in particular the closed configuration of the clasp. The vertical direction is the direction at right angles to the first two directions, oriented at right angles to the plane of the clasp (more specifically, of a blade or of a cover of the clasp).
In addition, the clasp according to the invention will be able to comprise one or two locking devices, substantially identical, arranged for example symmetrically on the clasp. Thus, the same references will be used to designate the components of the possible second locking device that are identical to the components of the first locking device, by adding the “′” symbol to differentiate these second references from the first.
The invention relies on a clasp provided with a locking mechanism using an actuation lever arranged directly in the cover of the clasp, even on a blade of the clasp, appearing notably as a movable part of the cover of the clasp. Such a part can for example appear as a simple cap on the cover. Such a solution makes it possible to achieve a pure esthetic appearance and a minimal bulk.
The two lateral blades 5, 5′ are substantially identical and the features of just the first lateral blade 5 will therefore be described in detail. A cover 6 is fixed onto this first lateral blade 5. This cover 6 is mounted to pivot in rotation about a cover axis 61 disposed at an end of the first blade 5, opposite its end linked to the central second blade 4. The cover 6 has an inverted U-shaped cross section, having a top face that is visible to a user, and two lateral walls, substantially at right angles to the top face, intended to laterally cover all of the clasp and its mechanism, notably the locking device, to conceal it, substantially mask it, and ensure the esthetic appearance of the solution. The cover 6 also comprises, on its end opposite the cover axis 61, a fixing device for an end of a wristlet length. On the embodiment, this fixing device comprises openings 62 arranged in the lateral walls of the cover 6 in order to receive a fixing bar for a wristlet end link. In the open position, the cover 6 can therefore be unfolded relative to the blades 4, 5 of the clasp by rotation about the clasp axis 61 and contribute to increasing the length of the clasp. In the closed position, the two covers 6, 6′ respectively of the two lateral blades 5, 5′ come to be positioned against one another continuously, thus forming the appearance of a single cover 60 of the clasp, as represented in
The locking device 10 of the first lateral blade 5 will now be described. It comprises, first of all, a locking element 1 mounted to rotate about a first axis 11. This locking element 1 comprises a form on a bottom end designed to cooperate with a complementary hooking element 4a arranged at the central part of the central second blade 4. According to the embodiment, this form is of hook type. As a variant, any other form allowing a mechanical locking between the locking element 1 and a complementary hooking element 4a is possible.
Also, one or more return springs 8a, 8b are provided to act on the locking element 1 to tend to position it in a position capable of engaging with the hooking element 4a of the central second blade 4, so as to lock the wristlet clasp. In the embodiment, two springs 8a, 8b are arranged around the first axis of rotation 11, symmetrically distributed about the longitudinal median plane I-I, as is represented in
The locking device 10 further comprises an actuation lever 2 arranged in the cover 6. More specifically, this actuation lever 2 appears as a part of the top surface of the cover 6. It extends over the entire length of the cover 6, and is articulated in rotation about a transverse second axis 21 at the longitudinal end of the cover 6 intended to receive a wristlet end link, opposite its end intended to be positioned at the center of the clasp in the closed position.
Finally, the locking device 10 comprises an intermediate element 3, linked on the one hand to the locking element 1 by a first link device and linked on the other hand to the actuation lever 2 by a second link device.
According to the embodiment, the locking element 1 and the intermediate element 3 of the locking device are linked in relative rotation about a first intermediate axis 31. The first link device is therefore an axis of rotation. On the other hand, the actuation lever 2 and the intermediate element 3 of the locking device are linked by a second link device comprising a groove 22, arranged on the actuation lever 2, within which a second intermediate axis 32 linking the actuation lever 2 and the intermediate element 3 is displaced and about which the actuation lever 2 and the intermediate element 3 can pivot with respect to one another. Such a second link device thus makes it possible to confer two degrees of freedom between the actuation lever 2 and the intermediate element 3. Naturally, it is perfectly possible to reverse this arrangement, by configuring the groove on the intermediate element 3 and the axis on the actuation lever 2.
In this embodiment, the first intermediate axis 31 and the second intermediate axis 32 are respectively arranged at the two longitudinal ends of the intermediate element 3. They are also positioned on either side of the first axis 11, in closed configuration of the clasp, as can be seen in
Naturally, the invention is not limited to the embodiment described. It can extend to any other solution in which at least one of said two link devices of the locking device is designed to confer two degrees of freedom on the two elements that it links. This link device can, for example, confer a first degree of freedom in rotation, and a second degree of freedom by displacement of translational type guided in a groove. This groove can extend in the longitudinal direction. As a variant, it could also have an orientation in another direction, for example vertical. The notion of “groove” should be considered in the broad sense of the term, it is not necessarily straight, and its trajectory can obviously be adapted to the kinematics of the various components of the locking device. Furthermore, according to the embodiment, the other link device confers a single degree of freedom. As a variant, it could also confer at least two degrees of freedom, like the at least one link device described above.
Thus, in a variant of the embodiment described, the first link device would therefore confer two degrees of freedom and the second link device a single degree of freedom. Furthermore, these degrees of freedom could rely on movement other than the rotations and translation described.
It should be noted that it appears, in the embodiment described, that the first axis 11, the first intermediate axis 31, the second intermediate axis 32, and the second axis 21, are distinct and parallel. They all have a transverse orientation.
The clasp according to the embodiment also comprises an element 7, particularly represented in
The embodiment relies on the arrangement or the linking of the locking device partly on a clasp cover. As a variant, the invention can still be implemented on a clasp without cover, or whose cover and blade are combined in one and the same element. In such a case, the actuation lever 2 would be directly mounted on a movable blade instead of a cover, for example as a movable part of said movable blade. According to another variant, the actuation lever 2 can take any other form, any other part of a clasp cover. Advantageously, in the closed position, it forms a substantially continuous surface with the rest of the clasp cover.
According to the embodiment, a gripping element 2a is arranged on the actuation lever 2, to facilitate the actuation thereof by a user. It is more specifically arranged at the central end of the actuation lever, opposite the second axis 21.
The embodiment described relies on a clasp with three blades. As mentioned previously, each lateral blade 5, 5′ can be locked onto and unlocked from the central blade 4 by a respective locking device 10, 10′. These two locking devices 10, 10′ are substantially identical, symmetrically distributed relative to a vertical transverse median plane P of the clasp, represented in
In the embodiment, it appears that the abovementioned different axes 11, 11′, 21, 21′, 31, 31′, 32, 32′, 51, 51′, 61, 61′, 71, 71′ of the clasp are all parallel, oriented transversely. Throughout this description, the notion of “axis” relates equally to the notion of geometrical axis and to the notion of physical axis. For example, in the embodiment, the first axis 11 is an axis of rotation of the locking element 1, which can be secured or not to the locking element 1. The same applies with respect to the other axes of the embodiment, in particular the second axis 21 and the two intermediate axes 31, 32.
As a variant, it is possible to imagine other embodiments in which all or some of these axes could have other orientations. Notably, the first axis 11 and the two intermediate axes 31, 32 could be at right angles to the second axis 21. As another variant, all these axes could remain parallel, but arranged differently.
Also, in the embodiment described, the axes of the locking device are pivoting axes. Alternatively, at least one of these axes could be an axis defining a translation trajectory. For example, the actuation lever 2 could notably take the form of a component that is movable in translation relative to the cover 6, in a direction corresponding substantially to the longitudinal direction of the cover 6.
Furthermore, the clasp could, as a variant, be a clasp with only two unfolding blades, and comprising a locking device between the two blades, as described previously. In this case, the abovementioned cover 6 can then correspond to all of the cover 60 of the clasp.
The invention relates also to a wristlet, wherein it comprises a locking device as described previously or a clasp as described previously. The invention relates also to a wristwatch comprising such a wristlet.
The operation of the clasp according to the embodiment will now be explained, in relation to
Number | Date | Country | Kind |
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20181588.3 | Jun 2020 | EP | regional |