Patent Application
20250143418
This application claims priority to European Patent Application No. 23207341.1 filed Nov. 2, 2023, the entire contents of which are incorporated herein by reference.
The invention relates to the field of jewellery or watch bracelets and relates in particular to a device for locking a push-piece for a clasp.
Many types of bracelet clasps exist. In particular, in the field of watchmaking, clasps comprising a single or double folding clasp, i.e. with two or three blades, are commonly used and are well known to a person skilled in the art.
By way of example, the clasp can include a push-piece attached to one blade and can be linked to a hook intended to engage with another blade when the clasp is closed. Pressing on the clasp moves the hook away from the other blade so that the clasp can be opened.
This type of clasp is thus quick and easy to open, simply by pressing the push-pieces. However, these advantages are exploited to steal watches when they are being worn by a user. The majority of luxury watch thefts involve switching the watches while they are being worn by a user, who is typically unaware at the time that his or her watch has been taken.
There is therefore a need to secure the clasp of a watch or piece of jewellery.
The invention overcomes the aforementioned drawbacks by proposing, to this end, a device for locking a clasp, which device comprises a push-piece which can move translatably in a support structure between a rest position in which it is intended to prevent the clasp from opening and an active position in which it is intended to no longer prevent the opening of the clasp. The locking device further includes a push-piece blocking member configured to occupy a locking state in which it immobilises the push-piece in the rest position, and an unlocking state in which it releases the push-piece translatably.
In particular embodiments, the invention can further include one or more of the following features, which must be considered singly or according to any combination technically possible.
In particular embodiments, the push-piece is connected to the support structure via a locking rod, the blocking member comprising a cam that is capable of moving relative to the push-piece so as to constitute an abutment for the locking rod when the blocking member occupies the locking state, and so as to move out of the path of the locking rod when the blocking member occupies the unlocking state.
In particular embodiments, the cam is rotatable and has a cam profile against which the locking rod abuts when the push-piece is urged from its rest position and when the blocking member occupies the locking state, said cam being provided with a radial notch in which the locking rod engages when the push-piece is in the active position and when the blocking member occupies the unlocking state.
In particular embodiments, the cam profile has a radial recess whose shape corresponds to that of the end of the locking rod, so as to prevent rotation of the cam when the push-piece is urged from its rest position and when the blocking member is in the locking state.
In particular embodiments, the blocking member includes a control element connected to the cam so as to rotate the cam when it is operated by a user.
In particular embodiments, the control element consists of a roller whose axis of rotation coincides with that of the cam.
In particular embodiments, the control element is held in a stable angular position by a jumper.
In particular embodiments, the control element has more than three stable positions, in only one of which is the blocking member in the unlocking state.
In particular embodiments, the cam profile has as many recesses as there are stable positions, except for the position in which the blocking member occupies the unlocking state, said recesses being distributed evenly.
In particular embodiments, the control element includes a guide mark whose position is representative of the locking or unlocking state of the control member.
In particular embodiments, the push-piece is biased to move towards its rest position by a spring and includes at least one guide rod slidingly engaged in the support structure, the latter further including at least one guide rod slidingly engaged in the push-piece.
In particular embodiments, the guide rod slidably engaged in the support structure has an axial abutment configured to rest against the support structure when the push-piece is in the rest position.
Another purpose of the invention relates to a folding clasp of a watch or a piece of jewellery, comprising at least two blades connected to each other so as to be able to move rotatably, and a locking device as described above, the support structure of which is formed by one of the blades of the clasp.
Other features and advantages of the invention will become apparent from the following detailed description, which is given by way of example and is by no means limiting, with reference to the accompanying drawings in which:
It should be noted that the figures are not necessarily drawn to scale for clarity purposes.
The invention relates to a locking device 10 for a clasp 20, for example of a watch or a piece of jewellery, in particular a folding clasp 20, for example with two or three blades. The locking device is shown in
Advantageously, the locking device 10 includes a blocking member 120 for blocking the push-piece 100, configured to occupy a locking state in which it immobilises the push-piece 100 in the rest position, and an unlocking state in which it releases the push-piece 100 such that it can translate.
The push-piece 100 is connected to the support structure 110 by means of a locking rod 111 attached without any degree of freedom to said support structure 110. The blocking member 120 is preferably housed in the push-piece 100 and comprises a cam 112 which can move relative to the push-piece 100, preferably rotatably. The cam 112 thus forms an abutment for the locking rod 111 when the blocking member 120 is in the locking state and is out of the path of the locking rod 111 when the blocking member 120 is in the unlocking state.
In particular, the cam 112 has a cam profile 113 against which the locking rod 111 abuts when the push-piece 100 is urged from its rest position and when the blocking member 120 occupies the locking state. The cam 112 is provided with a radial notch 114 in which the locking rod 111 engages when the push-piece 100 is in the active position and the blocking member 120 is in the unlocking state, as shown in
The blocking member 120 includes a control element 121 connected to the cam 112 and intended to be operated by a user such that it causes the cam to move. In the preferred example embodiment of the invention, the control element 121 consists of a roller provided with teeth, the axis of rotation of which coincides with that of the cam 112.
Advantageously, the blocking member 120 can comprise a spring 122 configured to hold the control element 121, and as a result the cam 112, in a stable angular position. The jumper 122 can be attached in the push-piece 100 and can rest against the control element 121, as shown in
The control element 121 includes a guide mark 123, whose position relative to the push-piece 100 is representative of the locking or unlocking state of the blocking member 120. In particular, in the preferred example embodiment of the invention, the blocking member 120 is in the unlocking state when the guide mark 123 of the control element 120, in this case constituted by a coloured mark, is in a central position, as visible in
Advantageously, the control element 121 can occupy a plurality of discrete stable positions, for example more than three, and in particular nine in the example embodiment shown in the figures. The blocking member 120 occupies the unlocking state in only one of these positions of the control element 121. Thus, a user of the watch can simply and quickly arrange the control member in the unlocking state, but this operation is made very complex for a person wishing to open the clasp 20 to steal the watch while it is on the user's wrist.
The cam profile 113 can advantageously have at least one radial recess 115, as can be seen in
This feature further increases the difficulty of unlocking the blocking member 120 when this operation is carried out in a hurry, for example during an attempted theft of a watch worn by a user.
Advantageously, the jumper 122 can be arranged so as to rest against the cam 112, in particular against a recess therein, as an alternative to the example embodiment of the invention shown in
The push-piece 100 includes at least one guide rod 101, preferably two, slidingly engaged in the support structure 110 and arranged on either side of the locking rod 111. The support structure 110 further includes at least one guide rod 116, preferably two, slidingly engaged in the push-piece 100 and arranged on either side of the locking rod 111. In the preferred example embodiment of the invention shown in the figures, the guide rods 116 of the support structure 110, engaged in the push-piece 100, are each arranged to bear against a spring 117 housed in said push-piece 100. The springs 117 are arranged so as to bias the push-piece 100 towards its rest position.
The guide rod 101 of the push-piece 100 slidably engaged in the support structure 110 has an axial abutment 102 at one of its ends opposite the push-piece 100, said abutment 102 being configured to rest against the support structure 110 when the push-piece 100 is in the rest position. In particular, in the preferred example embodiment of the invention, the abutment 102 is formed by a sole to which the ends of the guide rods 101 of the push-piece 100 are attached without any degree of freedom. As can be seen from the figures, the locking rod 111 can be engaged in a through-hole in the sole so as to slide relative thereto when the push-piece 100 is moved towards its active position.
By way of example, as shown in
In the example shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| 23207341.1 | Nov 2023 | EP | regional |
