The present invention concerns a clasp for a watch bracelet or strap. More specifically, the present invention concerns a watch bracelet clasp comprising a means of finely adjusting the bracelet length.
Clasps comprising means of fine adjustment of a watch bracelet length are already known in the state of the art. A clasp with fine adjustment of a bracelet length means a clasp which make it possible to adjust the bracelet length over a short travel for the best possible fit to optimise the comfort of the person wearing the watch. These clasps usually include an end link via which one of the bracelet strands is connected to the clasp cover. The end link is able to slide in a longitudinal direction of the clasp between a first “in” position in which it is housed in the clasp cover and a second “out” position in which it is outside from the clasp. Consequently, the available length for fine adjustment is determined by the travel of the end link between its first and second positions.
The end link cooperates via a toothed element with a rack toothing to index the end link position. When the toothed element is meshed with the rack toothing, the end link is immobilised. Elastic uncoupling means are provided to disengage the toothed element from its mesh with the rack toothing.
A clasp of the type described above is known, for example, from EP Patent No 11192833.9 filed under the name of the Applicant. According to one of its features, this clasp is fitted with an arresting means preventing the removal of the end link from the clasp cover. Owing to this feature, the connection between the clasp cover and the bracelet strand connected to the end link cannot be disassembled without destroying the link.
According to a preferred embodiment, the arresting means is removable, which, if necessary, allows the end link to be replaced when the wristwatch is returned to after-sales service. A threaded through hole, into which a first screw is screwed, is therefore provided in the end link. The tip of the first screw projects into a groove arranged in the bottom of the clasp cover. Since this groove is limited at each end by a stop member which marks the bottom of the groove, it is quite impossible to disassemble the fine adjustment end link once the first screw has been screwed in. Next, a cap is driven on or bonded to conceal the first screw and to keep the hole out of the user's sight. In that case however, the clasp is permanently impossible to disassemble. To overcome this drawback, it is proposed to conceal the first screw from the user's sight by means of a second screw arranged in the extension of the first screw. In this way, it remains possible to dismantle the assembly given that, in order to remove the first screw, the second screw simply needs to be taken out.
It is clear from the foregoing that, in order to ensure that it is possible to disassemble the end link, the clasp construction is relatively complex.
It is an object of the present invention to overcome the aforementioned drawbacks in addition to others by providing a watch bracelet clasp of simplified mechanical construction which operates reliably.
The present invention therefore concerns a watch bracelet clasp comprising a cover connected on a first side to a first bracelet strand and on a second side to a second bracelet strand, with connecting means inserted between the second bracelet strand and the clasp cover, the connecting means comprising an end link sliding along a longitudinal direction of the clasp between a first position, in which the end link is at least partially engaged in the clasp cover, and a second position in which the end link is outside from the clasp cover, the end link comprising a push-button which, when pressed, causes a toothed element to change from a first position, in which the toothed element is in mesh with a rack toothing, to a second position, in which the toothed element is released from its engagement with the rack toothing; the clasp being characterized in that the end link is provided with an arresting means preventing the removal of the end link from the clasp cover, said arresting means comprising at least one lug, which projects into a groove arranged in the bottom of the cover and which defines two end stop members.
As a result of these features, the present invention provides a watch bracelet clasp in which the fine adjustment mechanism of the bracelet length includes a sliding end link provided with at least one lug which projects into a groove arranged in the bottom of the clasp cover. The end link is captive or cannot be dismantled and the lug is not visible to the user, so that it is not necessary to take any measures to conceal the lug.
According to a complementary feature of the invention, the end link includes at least one skid which defines a sliding surface between the end link and the bottom of the cover.
As a result of this other feature, the contact surface between the end link and the bottom of the cover is reduced, which limits frictional forces and makes it easier to move the end link.
Other features and advantages of the present invention will appear more clearly from the following detailed description of an embodiment of the watch bracelet clasp according to the invention, this example being given solely by way of non-limiting illustration with reference to the annexed drawing, in which:
The present invention proceeds from the general inventive idea which consists in providing the sliding end link of a bracelet length fine adjustment system with an arresting means which is invisible to the user. Consequently, it is not necessary to take precautions to conceal the arresting means, which substantially simplifies the design of the clasp. Moreover, the end link slides on the bottom of the clasp cover on at least one skid, which reduces the surface contact between the end link and the cover. Frictional forces are thus reduced, so that it is easier to move the end link.
As can be seen upon examining
End link 10 includes a median knuckle 22 which nests between two end knuckles 24 carried by the link next to second bracelet strand 8. The links are assembled to each other by a bar 26 which passes unrestricted through knuckles 22 and 24 and which is held by two end screws 28.
End link 10 includes a groove 30 which extends transversely to the longitudinal axis of symmetry of clasp 1 and in which a V-shaped spring 32 is arranged. Spring 32, fixed in groove 30 by means of a screw 34, is covered by a push-button 36.
Push-button 36 takes substantially the form of a rectilinear actuation bar, which extends transversely to the longitudinal axis of symmetry of clasp 1 and which has a toothed element 38 at each end thereof, for example in the form of a semi-cylinder. These toothed elements 38 are intended to mesh with rack toothings 14. It will be clear that when end link 10 and its push button 36 are made to slide between the two wings 12 inside cover 2 of clasp 1, as illustrated in
It is observed upon examining
According to another feature of the invention, the bottom surface 42 of end link 10 is provided (see
Finally, a pair of stop members 50 is arranged to prevent any inadvertent activation of the fine adjustment device according to the invention when the unfolding clasp fastening system is operated.
It goes without saying that this invention is not limited to the embodiment that has just been described and that various simple alterations and variants can be envisaged by those skilled in the art without departing from the scope of the invention as defined by the claims annexed to this Patent Application. It will be noted in particular that the lugs and skids may be machined in the mass of the end link. Alternatively, the end link with its lugs and skids may be made in a single piece by metal injection moulding (MIM) using a metallic powder such as titanium or steel. Moreover, a diver's extension could be placed between the end link and the second bracelet strand.
Number | Date | Country | Kind |
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13155028.7 | Feb 2013 | EP | regional |
This application is a Continuation of U.S. application Ser. No. 14/102,835 filed Dec. 11, 2013, which claims priority from European Patent Application No. 13155028.7 filed Feb. 13, 2013, the entire disclosure of each of which is incorporated herein by reference.
Number | Date | Country | |
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Parent | 14102835 | Dec 2013 | US |
Child | 14645980 | US |